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Sample records for beech regeneration research

  1. Thinning in artificially regenerated young beech stands

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    Novák Jiří

    2015-12-01

    Full Text Available Although beech stands are usually regenerated naturally, an area of up to 5,000 ha year−1 is artificially regenerated by beech in the Czech Republic annually. Unfortunately, these stands often showed insufficient stand density and, consequently, lower quality of stems. Therefore, thinning methods developed for naturally regenerated beech stands are applicable with difficulties. The paper evaluates the data from two thinning experiments established in young artificially regenerated beech stands located in different growing conditions. In both experiments, thinning resulted in the lower amount of salvage cut in following years. Positive effect of thinning on periodic stand basal area increment and on periodic diameter increment of dominant trees was found in the beech stand located at middle elevations. On the other hand, thinning effects in mountain conditions were negligible. Thinning focusing on future stand quality cannot be commonly applied in artificially regenerated beech stands because of their worse initial quality and lower density. However, these stands show good growth and response to thinning, hence their management can be focused on maximising beech wood production.

  2. Beech forests of Azerbaijan: The modern condition, age structure and regeneration

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    Z.M. Hasanov

    2017-12-01

    Full Text Available Azerbaijan is a country with low forest cover, only 11.8% of the territory is covered with forests. All forests perform important water-soil-protection functions. In forests, naturally grow 107 species of trees and 328 shrubs species. Despite the fact that there are many species in dendroflora, only 10 tree species have economic value for the forest sector of the country. Beech (31.68%, oak (27.40% and hornbeam (26.01% are growing in 85.09% of forested areas. Beech forests are spread on 327 thousand hectares from 989,5 of total forest lands of he Republic. Beech forests are a source of high-quality wood and beech nuts. All beech forests grow in mountains at heights of 600–800 and 1600–1800 m above the sea level and performing important ecological functions. Until recently there were no problems with natural renewal of the beech forests, but now the regeneration of beech forests is alarming. In recent years, the productivity and density of beech forests decreased substantially, the natural regeneration proceeds unsatisfactorily and, consequently, reduction of beech forests takes place. We have researched 33,8 thousand hectares of beech forests of the Lesser Caucasus, their natural regeneration and made analysis of age structure of forests. Keywords: Fagus orientalis, Beech forests, Silviculture, Natural regeneration, Age class

  3. The role of granivorous rodents in beech forest regeneration in the Beskydy Mts. (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Suchomel, J.; Purchart, L.; Homolka, Miloslav

    2008-01-01

    Roč. 1, č. 2 (2008), s. 131-134 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : beech mast biomass * granivorous rodents * daily consumption rate * mountain beech forest * regeneration Subject RIV: EH - Ecology, Behaviour

  4. The influence of regeneration fellings on the development of artificially regenerated beech (Fagus sylvatica L.) plantations

    Czech Academy of Sciences Publication Activity Database

    Bednář, Pavel; Černý, J.

    2014-01-01

    Roč. 62, č. 5 (2014), s. 859-867 ISSN 1211-8516 Institutional support: RVO:67179843 Keywords : European beech * regeneration felling * artificial regeneration * height * DBH – the diameter at breast-height * quality * ISF – Indirect Site Factor Subject RIV: GK - Forestry

  5. Effect of stand edge on the natural regeneration of spruce, beech and Douglas-fir

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    Lumír Dobrovolný

    2012-01-01

    Full Text Available Our work aimed at studying the strategy of woody plants regeneration during the regeneration of a spruce stand with the admixture of beech and Douglas-fir by border cutting (NW-SE aspect on acidic sites of higher elevations in the Bohemian-Moravian Upland. Spruce is better adapted to bear shade than Douglas-fir. Nevertheless, in optimal light conditions up to a distance of ca. 35 m (about 16% DIFFSF from the stand edge, the Douglas-fir can put the spruce into danger as to height growth. By contrast to beech, the density of spruce is significantly higher within the distance of 45 m (about 15% DIFFSF from the stand edge but further on the situation would change to the benefit of beech. The density of Douglas-fir significantly dominates over beech within a distance of 35 m from the stand edge; from 55 m (less than 15% DIFFSF, the situation changes in favour of beech. Beech can survive in full shade deep in the stand core waiting for its opportunity to come. As compared to spruce and Douglas-fir, the height growth of beech was at all times significantly greater at a distance of 25 m from the stand edge. Converted to practical conditions, spruce and Douglas-fir with individually admixed beech seedlings showed good prosperity approximately up to a distance of one stand height from the edge. A mixture of spruce and beech did well at a greater distance but good prosperity at a distance of 2–3 stand heights was shown only by beech. Thus, border regeneration eliminates disadvantages of the climatic extremes of clear-cutting and specifics of shelterwood felling during which one – usually shade-tolerant tree species dominates in the natural regeneration (e.g. beech.

  6. Cascading effects of a highly specialized beech-aphid–fungus interaction on forest regeneration

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    Susan C. Cook-Patton

    2014-06-01

    Full Text Available Specialist herbivores are thought to often enhance or maintain plant diversity within ecosystems, because they prevent their host species from becoming competitively dominant. In contrast, specialist herbivores are not generally expected to have negative impacts on non-hosts. However, we describe a cascade of indirect interactions whereby a specialist sooty mold (Scorias spongiosa colonizes the honeydew from a specialist beech aphid (Grylloprociphilus imbricator, ultimately decreasing the survival of seedlings beneath American beech trees (Fagus grandifolia. A common garden experiment indicated that this mortality resulted from moldy honeydew impairing leaf function rather than from chemical or microbial changes to the soil. In addition, aphids consistently and repeatedly colonized the same large beech trees, suggesting that seedling-depauperate islands may form beneath these trees. Thus this highly specialized three-way beech-aphid–fungus interaction has the potential to negatively impact local forest regeneration via a cascade of indirect effects.

  7. THE ROLE OF TREEFALL COMPLEXES IN REGENERATION OF TREE SPECIES AND IN MAINTAINING OF BIOLOGICAL DIVERSITY OF NATURAL BEECH AND DARK CONIFEROUS-BEECH FORESTS OF THE UKRAINIAN CARPATHIANS

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    S. I. Ripa

    2017-06-01

    Full Text Available Understanding of maintaining biological diversity mechanisms is important for elaborating methods for the restoration of natural forests that most fully implement ecosystem functions. The objectives of work are: to identify intact beech and dark coniferous-beech forests of the Carpathians on the basis of analyzing history of nature management and field studies; to characterize the population structure of the main tree species in the intact forests of the Carpathians; to determine the renewal of various species of trees, shrubs, herbs and bryophytes to treefall microsites in the forest types studied. The objects of the research are monodominant beech forests and mixed (dark coniferous-beech forests of the Ukrainian Carpathians, in which beech (Fagus sylvatica, white fir (Abies alba and European spruce (Picea abies are the main dominant of tree sinusia. Monodominant beech forests (the age of stands 250–350 years were studied on 9 sample plots (from 1 to 1.05 ha laid in the Ugolsky forest range of the Carpathian Biosphere Reserve at an altitude of 600 to 1000 m above sea level, and also on the 2 sample plots (from 1 to 1.09 hectares laid in the Lower Volovets forestry at an altitude of 600–800 meters above sea level. Uneven-aged dark coniferous-beech forest (the age of forest stands is 250–300 years old was explored on one sample plot (1.2 ha laid in the Podlisnivsky forestry of the Carpathian National Park at an altitude of 750 m above sea level. Population analysis of the main tree and shrub species as well as geobotanical releves was made on the sample plots. Treefall microsite complexes were investigated to identify the peculiarities in the location of tree undergrowth, herb and moss species in beech and mixed forests. The following elements of treefall microsite complex were singled out: treefall pit, treefall mound and tree trunk. At each treefall microsite complex the research was carried out according to the following scheme: an

  8. Ungulate Impact on Natural Regeneration in Spruce-Beech-Fir Stands in Černý důl Nature Reserve in the Orlické Hory Mountains, Case Study from Central Sudetes

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    Zdeněk Vacek

    2014-11-01

    Full Text Available The paper presents the results of a study on tree regeneration of forest stands in the Černý důl Nature Reserve, which is situated in the Orlické hory Mountains Protected Landscape area in the Czech Republic. Research was conducted in a spruce-beech stand with an admixture of silver fir, sycamore maple and rowan on two comparative permanent research plots (PRPs (PRP 1—fenced enclosure and PRP 2—unfenced. Typological, soil, phytosociological and stand characteristics of the two PRPs are similar. The results showed that ungulate browsing is a limiting factor for successful development of natural regeneration of autochthonous tree species. The population of tree species of natural regeneration on the fenced plot (PRP 1 is sufficient in relation to the site and stand conditions. However, natural regeneration on PRP 2 is considerably limited by browsing. Damage is greatest to fir, sycamore maple and rowan; less severe to beech; and the least to spruce.

  9. EXPERIMENTAL RESEARCH CONCERNING THE OPTIMAL DIMENSIONS OF AN ELASTIC STRUCTURE OF BEECH WOOD PARQUET

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    Olimpia-Minerva ȚURCAȘ (DIACONU

    2015-12-01

    Full Text Available This paper presents the results of the experimental research concerning the modulus of elasticity and the average value of the bending strength in case of beech (Fagus sylvatica L. wood. The investigations were performed according to SR EN 408-2004. The results of the research have been analysed in order to establish the variable parameters to be considered for the final experimental research focused on beech wood floor structures that meet the necessary requirements for the sports halls applications. The research presented in the paper is a part of the study theme of the Ph. D. thesis, which investigates the flooring structures able to support the requirements of sports halls activities, different from one sport to another.

  10. Utilization of beech

    Energy Technology Data Exchange (ETDEWEB)

    Heckemann, H

    1980-01-01

    The paper reviews (for beech in W. Germany, and, in many cases for competitive hardwoods/softwoods): regional felling statistics/assortment structures; age class structures; profitability/prices; import/export trends; sales trends (for beech timber from Hesse State Forests); beech plywood production; ownership of forests, and specific uses of beech, including as an energy source, in sleepers, and in furniture.

  11. Beech Bark Disease

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    David R. Houston; James T. O' Brien

    1983-01-01

    Beech bark disease causes significant mortality and defect in American beech, Fagus grandifolia (Ehrh.). The disease results when bark, attacked and altered by the beech scale, Cryptococcus fagisuga Lind., is invaded and killed by fungi, primarily Nectria coccinea var. faginata Lohman, Watson, and Ayers, and sometimes N. galligena Bres.

  12. Climate Change Impairs Nitrogen Cycling in European Beech Forests.

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    Michael Dannenmann

    Full Text Available European beech forests growing on marginal calcareous soils have been proposed to be vulnerable to decreased soil water availability. This could result in a large-scale loss of ecological services and economical value in a changing climate. In order to evaluate the potential consequences of this drought-sensitivity, we investigated potential species range shifts for European beech forests on calcareous soil in the 21st century by statistical species range distribution modelling for present day and projected future climate conditions. We found a dramatic decline by 78% until 2080. Still the physiological or biogeochemical mechanisms underlying the drought sensitivity of European beech are largely unknown. Drought sensitivity of beech is commonly attributed to plant physiological constraints. Furthermore, it has also been proposed that reduced soil water availability could promote nitrogen (N limitation of European beech due to impaired microbial N cycling in soil, but this hypothesis has not yet been tested. Hence we investigated the influence of simulated climate change (increased temperatures, reduced soil water availability on soil gross microbial N turnover and plant N uptake in the beech-soil interface of a typical mountainous beech forest stocking on calcareous soil in SW Germany. For this purpose, triple 15N isotope labelling of intact beech seedling-soil-microbe systems was combined with a space-for-time climate change experiment. We found that nitrate was the dominant N source for beech natural regeneration. Reduced soil water content caused a persistent decline of ammonia oxidizing bacteria and therefore, a massive attenuation of gross nitrification rates and nitrate availability in the soil. Consequently, nitrate and total N uptake of beech seedlings were strongly reduced so that impaired growth of beech seedlings was observed already after one year of exposure to simulated climatic change. We conclude that the N cycle in this

  13. Climate Change Impairs Nitrogen Cycling in European Beech Forests.

    Science.gov (United States)

    Dannenmann, Michael; Bimüller, Carolin; Gschwendtner, Silvia; Leberecht, Martin; Tejedor, Javier; Bilela, Silvija; Gasche, Rainer; Hanewinkel, Marc; Baltensweiler, Andri; Kögel-Knabner, Ingrid; Polle, Andrea; Schloter, Michael; Simon, Judy; Rennenberg, Heinz

    2016-01-01

    European beech forests growing on marginal calcareous soils have been proposed to be vulnerable to decreased soil water availability. This could result in a large-scale loss of ecological services and economical value in a changing climate. In order to evaluate the potential consequences of this drought-sensitivity, we investigated potential species range shifts for European beech forests on calcareous soil in the 21st century by statistical species range distribution modelling for present day and projected future climate conditions. We found a dramatic decline by 78% until 2080. Still the physiological or biogeochemical mechanisms underlying the drought sensitivity of European beech are largely unknown. Drought sensitivity of beech is commonly attributed to plant physiological constraints. Furthermore, it has also been proposed that reduced soil water availability could promote nitrogen (N) limitation of European beech due to impaired microbial N cycling in soil, but this hypothesis has not yet been tested. Hence we investigated the influence of simulated climate change (increased temperatures, reduced soil water availability) on soil gross microbial N turnover and plant N uptake in the beech-soil interface of a typical mountainous beech forest stocking on calcareous soil in SW Germany. For this purpose, triple 15N isotope labelling of intact beech seedling-soil-microbe systems was combined with a space-for-time climate change experiment. We found that nitrate was the dominant N source for beech natural regeneration. Reduced soil water content caused a persistent decline of ammonia oxidizing bacteria and therefore, a massive attenuation of gross nitrification rates and nitrate availability in the soil. Consequently, nitrate and total N uptake of beech seedlings were strongly reduced so that impaired growth of beech seedlings was observed already after one year of exposure to simulated climatic change. We conclude that the N cycle in this ecosystem and here

  14. Listening to old beech and young cherry trees - long-term research in the Alleghenies

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    Susan L. Stout; Coeli M. Hoover; Todd E. Ristau

    2006-01-01

    Long-term research results have been a foundation of forestry practice on the Allegheny Plateau since the 1970s. This includes results from monitoring reference conditions in areas set aside for this purpose and from long-running manipulative studies, some dating back to the 1920s. The success of long-term research in this region reflects the commitment of a handful of...

  15. Regeneration

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    George A. Schier; Wayne D. Shepperd; John R. Jones

    1985-01-01

    There are basically two approaches to regenerating aspen stands-sexual reproduction using seed, or vegetative regeneration by root suckering. In the West, root suckering is the most practical method. The advantage of having an existing, well established root system capable of producing numerous root suckers easily outweighs natural or artificial reforestation in the...

  16. Effect of the density of transplants in reforestation on the morphological quality of the above-ground part of European beech (Fagus sylvatica L. six years after planting

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    Kateřina Houšková

    2013-01-01

    Full Text Available Quality of the above-ground part of European beech planted at different densities and spacing patterns for the purpose of artificial forest regeneration was monitored 3, 4 and 6 years after planting. The initial numbers of beech transplants were 5,000 pcs.ha−1, 10,000 pcs.ha−1, 15,000 pcs.ha−1 and 20,000 pcs.ha−1. The spacing pattern of transplants was either square or rectangular nearly in all variants: 1.4 × 1.4 m, 2 × 1 m, 1 × 1 m, 0.8 × 0.8 m, 1 ×0.65 m, 0.7 × 0.7 m and 1 × 0.5 m. Conclusions following out from the research are as follows: 1. neither the chosen density of transplants nor their spacing pattern had an essential influence on the after-planting loss or damage of trees; 2. through the planting of larger-diameter transplants it is possible to achieve canopy closure more rapidly as well as faster growth of the plantation; these beech plants keep the edge in growth and quality even 6 years after planting; 3. the higher is the beech plantation density, the less individuals occur in such a plantation with inappropriate stem form; 4. beech plants of the worst quality were found on plots with the lowest initial density of transplants (5,000 and 10,000 pcs.ha−1, yet the number of promising trees was sufficient even there. Thus, none of the experimental numbers of transplants per hectare or spacing arrangements of the European beech transplants can be claimed as inappropriate; however, further monitoring of the plots is necessary.

  17. Cancer-related aspects of regeneration research: a review

    International Nuclear Information System (INIS)

    Donaldson, D.J.; Mason, J.M.

    1975-01-01

    Tissue regeneration is simply the replacement of lost cells of a tissue by those remaining. Epimorphic regeneration involves dedifferentiation of many tissues and their organization into a blastema which eventually differentiates into the missing part, usually an appendage. A detailed comparison of the cell membrane changes occurring in epimorphic regeneration, tissue regeneration and cancer can contribute to greater understanding of the differences between normal and tumor cells. Further, there is evidence that epimorphic regeneration fields may in some instances suppress tumor induction and control existing tumors. This influence may be mediated by bioelectric fields, which are ubiquitous in nature and appear to control many cellular events. Disruption of these bioelectric fields suppresses epimorphic regeneration and may lead to cancer in mammals, while applied electric fields alter regenerative events and cause tumor regression. Studies on x-radioinduced regeneration suppression in relation to mutagenesis are also reviewed

  18. Assessment of beech scale resistance in full- and half-sibling American beech families

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    Jennifer L. Koch; David W. Carey; Mary E. Mason; C. Dana Nelson

    2010-01-01

    A beech bark disease infested American beech tree (Fagus grandifolia Ehrh.) and two uninfested trees were selected in a mature natural stand in Michigan, USA, and mated to form two full-sib families for evaluating the inheritance of resistance to beech scale (Cryptococcus fagisuga Lind.), the insect element of beech bark disease....

  19. Regeneration Responses to Management for Old-Growth Characteristics in Northern Hardwood-Conifer Forests

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    Aviva J. Gottesman

    2017-02-01

    Full Text Available Successful tree regeneration is essential for sustainable forest management, yet it can be limited by the interaction of harvesting effects and multiple ecological drivers. In northern hardwood forests, for example, there is uncertainty whether low-intensity selection harvesting techniques will result in adequate and desirable regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called “structural complexity enhancement” (SCE can accelerate the development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments with high levels of retention: single-tree selection, group selection, and SCE. Regeneration density and diversity can be limited by differing treatment effects on or interactions among light availability, competitive environment, substrate, and herbivory. To explore these relationships, manipulations and controls were replicated across 2 ha treatment units at two Vermont sites. Forest inventory data were collected pre-harvest and periodically over 13 years post-harvest. We used mixed effects models with repeated measures to evaluate the effect of treatment on seedling and sapling density and diversity (Shannon–Weiner H’. The treatments were all successful in recruiting a sapling class with significantly greater sapling densities compared to the controls. However, undesirable and prolific beech (Fagus americana sprouting dominates some patches in the understory of all the treatments, creating a high degree of spatial variability in the competitive environment for regeneration. Multivariate analyses suggest that while treatment had a dominant effect, other factors were influential in driving regeneration responses. These results indicate variants of uneven-aged systems that retain or enhance elements of stand structural complexity—including old-growth characteristics

  20. Research Note Effects of previous cultivation on regeneration of ...

    African Journals Online (AJOL)

    We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...

  1. Thermopower of beech wood biocarbon

    Science.gov (United States)

    Smirnov, I. A.; Smirnov, B. I.; Orlova, T. S.; Sulkovski, Cz.; Misiorek, H.; Jezowski, A.; Muha, J.

    2011-11-01

    This paper reports on measurements of the thermopower S of high-porosity samples of beech wood biocarbon with micron-sized sap pores aligned with the tree growth direction. The measurements have been performed in the temperature range 5-300 K. The samples have been fabricated by pyrolysis of beech wood in an argon flow at different carbonization temperatures ( T carb). The thermopower S has been measured both along and across the sap pores, thus offering a possibility of assessing its anisotropy. The curves S( T carb) have revealed a noticeable increase of S for T carb biocarbons, which suggests that for T carb ˜ 1000°C they undergo a phase transition of the insulator-(at T carb 1000°C) type. The existence of this transition is attested also by the character of the temperature dependences S( T) of beech wood biocarbon samples prepared at T carb above and below 1000°C.

  2. Impacts of a water stress followed by an early frost event on beech (Fagus sylvatica L.) susceptibility to Scolytine ambrosia beetles - Research strategy and first results

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    La Spina, Sylvie; de Cannière, Charles; Molenberg, Jean-Marc; Vincke, Caroline; Deman, Déborah; Grégoire, Jean-Claude

    2010-05-01

    Climate change tends to induce more frequent abiotic and biotic extreme events, having large impacts on tree vitality. Weakened trees are then more susceptible to secondary insect outbreaks, as it happened in Belgium in the early 2000s: after an early frost event, secondary Scolytine ambrosia beetles attacks were observed on beech trees. In this study, we test if a combination of stress, i.e. a soil water deficit preceding an early frost, could render trees more attractive to beetles. An experimental study was set in autumn 2008. Two parcels of a beech forest were covered with plastic tents to induce a water stress by rain interception. The parcels were surrounded by 2-meters depth trenches to avoid water supply by streaming. Soil water content and different indicators of tree water use (sap flow, predawn leaf water potential, tree radial growth) were followed. In autumn 2010, artificial frost injuries will be inflicted to trees using dry ice. Trees attractivity for Scolytine insects, and the success of insect colonization will then be studied. The poster will focus on experiment setting and first results (impacts of soil water deficit on trees).

  3. Full Length Research Paper Plant regeneration of Michelia ...

    African Journals Online (AJOL)

    Michelia champaca L. is a woody ornamental tree species which has high commercial value to be used as a basic material for perfume, cosmetic, and medicine. The development of an efficient plant regeneration system for M. champaca is essential for the production of Champaca planting material and precondition for ...

  4. Comparisons of protein profiles of beech bark disease resistant and susceptible American beech (Fagus grandifolia)

    Science.gov (United States)

    Mary E. Mason; Jennifer L. Koch; Marek Krasowski; Judy. Loo

    2013-01-01

    Beech bark disease is an insect-fungus complex that damages and often kills American beech trees and has major ecological and economic impacts on forests of the northeastern United States and southeastern Canadian forests. The disease begins when exotic beech scale insects feed on the bark of trees, and is followed by infection of damaged bark tissues by one of the...

  5. Comparison of protein profiles of beech bark disease-resistant or beech bark disease-susceptible American beech

    Science.gov (United States)

    Mary E. Mason; Marek Krasowski; Judy Loo; Jennifer. Koch

    2011-01-01

    Proteomic analysis of beech bark proteins from trees resistant and susceptible to beech bark disease (BBD) was conducted. Sixteen trees from eight geographically isolated stands, 10 resistant (healthy) and 6 susceptible (diseased/infested) trees, were studied. The genetic complexity of the sample unit, the sampling across a wide geographic area, and the complexity of...

  6. Estimation of beech tree transpiration in relation to their social status in forest stand

    International Nuclear Information System (INIS)

    Střelcová, K.; Matejka, F.; Minďáš, J.

    2002-01-01

    The results of sap flow continuous measurements by a tree-trunk heat balance method (THB) on beech model trees are analysed in this paper. Experimental research works were carried out in a mature mixed fir-spruce-beech stand in the research area Pol'ana - Hukavský Grúň (φ = 48°39', λ = 19°29', H = 850 m a.s.l.) in UNESCO Biosphere Reserve on two co-dominant and one sub-dominant beech trees. A mathematical model of daily transpiration dynamics was proposed for a quantitative analysis of the daily course of sap flow intensity. The model works on a one-tree level and enables to consider the influence of the tree social position in the stand on the sap flow intensity of model beech trees and to express the dependence of sap flow intensity on the tree height and crown projection

  7. [Research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration].

    Science.gov (United States)

    Liang, Hang; Deng, Xiangyu; Shao, Zengwu

    2017-10-01

    To summarize the research progress of intervertebral disc endogenous stem cells for intervertebral disc regeneration and deduce the therapeutic potential of endogenous repair for intervertebral disc degeneration. The original articles about intervertebral disc endogenous stem cells for intervertebral disc regeneration were extensively reviewed; the reparative potential in vivo and the extraction and identification in vitro of intervertebral disc endogenous stem cells were analyzed; the prospect of endogenous stem cells for intervertebral disc regeneration was predicted. Stem cell niche present in the intervertebral discs, from which stem cells migrate to injured tissues and contribute to tissues regeneration under certain specific microenvironment. Moreover, the migration of stem cells is regulated by chemokines system. Tissue specific progenitor cells have been identified and successfully extracted and isolated. The findings provide the basis for biological therapy of intervertebral disc endogenous stem cells. Intervertebral disc endogenous stem cells play a crucial role in intervertebral disc regeneration. Therapeutic strategy of intervertebral disc endogenous stem cells is proven to be a promising biological approach for intervertebral disc regeneration.

  8. Research on mass transfer and actual performance of the membrane regeneration air-conditioning system

    International Nuclear Information System (INIS)

    Li, Xiu-Wei; Zhang, Xiao-Song; Chen, Qing

    2015-01-01

    Highlights: • Experimental research has been made on the membrane air-conditioning system. • We develop mass transfer models for the membrane regeneration process. • The paper exposes the actual performance of the system. • Increase of membrane pairs improves the performance. - Abstract: Absorption air-conditioning system has great advantages in energy conservation and environmental protection. To improve the performance of the traditional system, the membrane regeneration absorption system was proposed. Its COP could approach 6 by regenerating absorbent solution with the ion exchange membranes. However, the theoretical conclusion has not been supported by the experiment. This paper presents the experimental research of the membrane regeneration process. It has investigated the mass transfer process, energy efficiency and actual performance under different working conditions. Based on that, a mass transfer model has been developed and the influences of some key parameters have been exposed. It found the regeneration performance is mainly influenced by the current intensity. The calculation results with the model agree well the experimental data. The actual efficiency was lower than 50%, caused by energy loss in heat and electrochemical reactions. The actual COP is between 1 and 3, lower current intensity and more membrane pairs could improve it.

  9. Meniscus repair and regeneration: review on current methods and research potential

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    C Scotti

    2013-01-01

    Full Text Available Meniscus regeneration is an unsolved clinical challenge. Despite the wide acceptance of the degenerative consequences of meniscectomy, no surgical procedure has succeeded to date in regenerating a functional and long-lasting meniscal fibrocartilage. Research proposed a number of experimental approaches encompassing all the typical strategies of regenerative medicine: cell-free scaffolds, gene therapy, intra-articular delivery of progenitor cells, biological glues for enhanced bonding of reparable tears, partial and total tissue engineered meniscus replacement. None of these approaches has been completely successful and can be considered suitable for all patients, as meniscal tears require specific and patient-related treatments depending on the size and type of lesion. Recent advances in cell biology, biomaterial science and bioengineering (e.g., bioreactors have now the potential to drive meniscus regeneration into a series of clinically relevant strategies. In this tutorial paper, the clinical need for meniscus regeneration strategies will be explained, and past and current experimental studies on meniscus regeneration will be reported.

  10. Influence of xylem ray integrity and degree of polymerization on bending strength of beech wood decayed by Pleurotus ostreatus and Trametes versicolor

    Science.gov (United States)

    Ehsan Bari; Reza Oladi; Olaf Schmidt; Carol A. Clausen; Katie Ohno; Darrel D. Nicholas; Mehrdad Ghodskhah Daryaei; Maryam Karim

    2015-01-01

    The scope of this research was to evaluate the influence of xylem ray (XR) and degree of polymerization (DP) of holocellulose in Oriental beech wood (Fagus orientalis Lipsky.) on impact bending strength against two white-rot fungi. Beech wood specimens, exposed to Pleurotus ostreatus and Trametes versicolor, were evaluated for...

  11. Genome-wide association study identifies a major gene for beech bark disease resistance in American beech (Fagus grandifolia Ehrh.)

    Science.gov (United States)

    Irina Ćalić; Jennifer Koch; David Carey; Charles Addo-Quaye; John E. Carlson; David B. Neale

    2017-01-01

    Background: The American Beech tree (Fagus grandifolia Ehrh.), native to eastern North America, is ecologically important and provides high quality wood products. This species is susceptible to beech bark disease (BBD) and is facing high rates of mortality in North America. The disease occurs from an interaction between the woolly beech scale...

  12. Hypoxylon species on beech and other broadleaves

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    Milijašević Tanja

    2004-01-01

    Full Text Available Fungi in the genus Hypoxylon cause wood decay and most of them are saprophytes on dead wood or parasites of weakness. The following species in this genus were identified in this study performed at several localities in Serbia and Montenegro: H. deustum, H. fragiforme, H. nummularium, H. multiforme, H. rubiginosum and H. fuscum. Among them the most significant species is H. deustum, the fungus causing root and butt rot of standing beech trees. It was recorded from all coppice and high forests of beech. This paper presents the morphological characteristics of the recorded fungi their range, plant hosts and significance.

  13. Attitudes of ornamental trees and shrubs producers towards nursery production of ornamental beech cultivars in Serbia

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    Nonić Marina

    2016-01-01

    Full Text Available European beech (Fagus sylvatica L. is, along with its significance as a forest species, renowned as an ornamental species, due to its numerous cultivars. Ornamental beech cultivars are planted in various green spaces, but a small number of such trees have ascertained in Serbia. For the time being, production of beech cultivars is represented in a very small number of nurseries, with a negligible share of those seedlings in their total assortment. The aim of this research is to study the attitudes of ornamental trees and shrubs producers towards the nursery production of ornamental beech cultivars, and possibilities of its improvements in Serbia. “Door to door” survey and in-depth interviews were used as research techniques. Surveys with the representatives of 65 nurseries in Serbia (in the selected statistical region Šumadija and Western Serbia were conducted in the first stage of data collection. In the second stage of data collection were interviewed the representatives of the 10 nurseries who, during the survey, pointed out that they produce ornamental beech cultivars. Nurserymen’s attitudes suggest that there is a possibility to improve the production of ornamental beech cultivars in Serbia, with the appropriate support measures and increased interest of customers on the market, i.e. with the provision of subsidies for the production of seedlings and greater use of cultivars by utility companies in the cities of Serbia. [Projekat Ministarstva nauke Republike Srbije, br. ТP 31041: Establishment of forest plantations to increase the afforested areas in Serbia

  14. Extra-zonal beech forests in Tuscany: structure, diversity and synecologic features

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    Viciani D

    2011-07-01

    Full Text Available The present paper focuses on the structural, synecological and floristic diversity features of beech-dominated forest communities in four major areas of the Antiapenninic Tyrrhenian system in Tuscany: Metalliferous hills, mountains to the south of Mt. Amiata, volcanic area of the upper Lente valley and Mt. Cetona. These are relict woodlands of Holo-Pleistocene origin with a special ecological and conservation value due to their extrazonal location in lowland submediterranean areas. Results show substantial among-area differences in structure, synecology and plant species composition, but in general a potential for coppices to reach the tall forest stage, as demonstrated by the old-growth stands of Pietraporciana and Sassoforte. Compared with montane Apenninic beechwoods, the relatively rich flora of the studied communities include thermophilous species with a southern Apennine-Balkan distribution, making their syntaxonomical position unclear. Closer affinities are found with the calcicolous Beech Forests of the association and with the silicicolous ones of the . Based on the Natura 2000 system, all the examined communities belong to the priority Habitat “Apennine beech forests with and ” (code: 9210*. Due their relict nature, these biotopes appear vulnerable to climate changes and to a production-oriented forest management. Criteria of naturalistic silviculture should instead promote the dynamic development of these communities towards tall forests and their natural regeneration.

  15. European Union - Space of Regeneration, Learning and Innovation in the Context of Sustainable Multidisciplinary Research

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    Florin Răzvan Bălășescu

    2010-07-01

    Full Text Available Objective The Lisbon Strategy set a new goal for the EU economy: the transition to a knowledge based economy, competitive and sustainable at macro and regional levels, by creating the European Research Area – a geographic area without frontiers for researches, where scientific resources are better managed to create more jobs and improve Europe's competitiveness. That means an interaction between specific and multidisciplinary research network. Approach However, general research methodology sustains the importance of static and revolutionary specific criteria of Scientific Research Programs but also reveals the natural process of multidisciplinary researches. In this context, the European Union could be regarded as a specific and multidisciplinary research area, as a network of flows, connections, relationships, interdependencies, and interferences between natural - experimental and social-humanistic research spheres (economics, management, sociology and complex systems ecology. Prior Work: In this respect some researchers suggested that both natural and social systems could be considered as multidisciplinary complex adaptive systems consisting of specific cluster network connections ( in the form of biotic and abiotic nodes, respectively, the competitive and regional poles with the ability to continuous self-organizing, learning and regenerating process especially in crisis situations. Implications and Value Paper Utility The present paper might be useful to illustrate the contribution of technical-economic and socio-ecological researches to increasing the sustainability framework of European Research Area by considering the transition from the R&D approach (development through research process to the L&D approach (development through learning process.

  16. Climate change impairs processes of soil and plant N cycling in European beech forests on marginal soil

    Science.gov (United States)

    Tejedor, Javier; Gasche, Rainer; Gschwendtner, Silvia; Leberecht, Martin; Bimüller, Carolin; Kögel-Knabner, Ingrid; Pole, Andrea; Schloter, Michael; Rennenberg, Heinz; Simon, Judy; Hanewinkel, Marc; Baltensweiler, Andri; Bilela, Silvija; Dannenmann, Michael

    2014-05-01

    Beech forests of Central Europe are covering large areas with marginal calcareous soils, but provide important ecological services and represent a significant economical value. The vulnerability of these ecosystems to projected climate conditions (higher temperatures, increase of extreme drought and precipitation events) is currently unclear. Here we present comprehensive data on the influence of climate change conditions on ecosystem performance, considering soil nitrogen biogeochemistry, soil microbiology, mycorrhiza ecology and plant physiology. We simultaneously quantified major plant and soil gross N turnover processes by homogenous triple 15N isotope labeling of intact beech natural regeneration-soil-microbe systems. This isotope approach was combined with a space for time climate change experiment, i.e. we transferred intact beech seedling-soil-microbe mesocosms from a slope with N-exposure (representing present day climate conditions) to a slope with S exposure (serving as a warmer and drier model climate for future conditions). Transfers within N slope served as controls. After an equilibration period of 1 year, three isotope labeling/harvest cycles were performed. Reduced soil water content resulted in a persistent decline of ammonia oxidizing bacteria in soil (AOB). Consequently, we found a massive five-fold reduction of gross nitrification in the climate change treatment and a subsequent strong decline in soil nitrate concentrations as well as nitrate uptake by microorganisms and beech. Because nitrate was the major nutrient for beech in this forest type with little importance of ammonium and amino acids, this resulted in a strongly reduced performance of beech natural regeneration with reduced N content, N metabolite concentrations and plant biomass. These findings provided an explanation for a large-scale decline of distribution of beech forests on calcareous soils in Europe by almost 80% until 2080 predicted by statistical modeling. Hence, we

  17. Beech wood export and import trends in Serbia

    Directory of Open Access Journals (Sweden)

    Ranković Nenad

    2004-01-01

    Full Text Available By the establishment and analysis of the model of beech wood export and export trends in Serbia (by quantity and value, for the period 1988-2002 the regularities of the changes of their magnitude in time were defined. On this basis, the relations of import and export trends were analyzed. Based on the study elements, the potentials of beech sawlog and beech sawnwood export, as well as the potential economic effects, were pointed out.

  18. Edaphic potentials of beech forests on Brezovica

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    Knežević Milan

    2002-01-01

    Full Text Available The study deals with the soils in the montane beech forest (Fagetum moesiacae montanum Jov. 53 in the management units "Južni Kuèaj II" and "Bogovina I", on the mountain massif Brezovica. Soil genesis in the beech forests of Brezovica, along with vegetation and relief, was affected by the character of parent rock. The study soils occur over two types of bedrock: limestone and argilloschist The soil types and sub-types are defined based on the profile morphology, parent rock and pedogenetic processes Two types of soil were analysed on limestone: black earth (calcomelanosol and brown soil (calcocambisol. Two sub-types of black earth were defined: organomineral and brownised. There are two varieties of organomineral black earth: colluvial and lithic. Also two sub-types of brown soils were defined and: typical and illimerised. The soils on limestone are characterised by great spatial variability. Different combinations of soil formations occur on a small area. Soil combinations consist of two or three development phases, the most represented of which are the following: organomineral black earth - brownised black earth; organomineral black earth - brownised black earth - typical brown soil; typical brown soil - illimerised soil Typical brown soil is formed on argilloschists and it occurs in two forms: medium deep, medium skeletal acid brown soil and deep, poorly skeletal acid brown soil The most productive sites of the montane beech forest on Brezovica are deep acid brown soils and the soil combination: typical brown soil - illimerised soil on limestone.

  19. Microbial Activity in Forest Soil Under Beech, Spruce, Douglas Fir and Fir

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    Hajnal-Jafari Timea

    2016-08-01

    Full Text Available The aim of this research was to investigate the microbial activity in forest soil from different sites under deciduous and coniferous trees in Serbia. One site on Stara planina was under beech trees (Fagus sp. while another under mixture of spruce (Picea sp. and Douglas fir (Pseudotsuga sp.. The site on Kopaonik was under mixture of beech (Fagus sp. and spruce (Picea sp. trees. The site on Tara was dominantly under fir (Abies sp., beech (Fagus sp. and spruce (Picea sp.. The total number of bacteria, the number of actinobacteria, fungi and microorganisms involved in N and C cycles were determined using standard method of agar plates. The activities of dehydrogenase and ß-glucosidase enzymes were measured by spectrophotometric methods. The microbial activity was affected by tree species and sampling time. The highest dehydrogenase activity, total number of bacteria, number of actinobacteria, aminoheterotrophs, amylolytic and cellulolytic microorganisms were determined in soil under beech trees. The highest total number of fungi and number of pectinolytic microorganisms were determined in soil under spruce and Douglas fir trees. The correlation analyses proved the existence of statistically significant interdependency among investigated parameters.

  20. Some Indicators of Beech Forests Vitality in the Republic of Serbia in Period 2004-2009

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    Radovan Nevenić

    2011-06-01

    Full Text Available Background and Purpose: Forests monitoring is one of the largest forest bio-monitoring systems that is carried out in order to record changes by using the most important environmental parameters. The National Focal Centre for forest monitoring in the Republic of Serbia, within the Institute of Forestry of the Republic of Serbia has been taking an active part in an international program of ICP Forest, with a view to improving its working activities and harmonizing them with other approaches to monitoring forests and forest ecosystems. Material and Methods: In order to determine forest ecosystem processes, it is necessary to carry out detailed research of ecological and socio-economic consequences of forest deterioration and to study the impacts of regional climate changes on forest communities. In the period from 2004 to 2009, observations were performed on 130 sample plots and data necessary for further analysis were collected. These plots are systematically arranged in either a 16x16 km or a 4 x 4 km grid system. The main parameters assessed on the sample plots are the degree of defoliation and discolouration as well as the extent of damage. A comparative analysis of the data obtained in this period will provide a better insight into the present state of beech forests in Serbia as well the effects of defoliation and discolouration trends. Results and Conclusion: Beech is the most common broadleaved tree species on the Level I sample plots. Its health state is the result of adverse effects of complex factors of abiotic and biotic origin (i.e. effects of both living organisms and complex natural processes within the beech forests habitats. This paper presents some indicators of beech forest vitality whose occurrence show certain regularity and which can be interpreted as a trend. The annual values of the health state elements and the fluctuations of these parameters from year to year present important indicators of vitality of beech forests in

  1. Dead wood in European beech (Fagus sylvatica) forest reserves

    NARCIS (Netherlands)

    Christensen, M.; Hahn, K.; Mountford, E.P.; Ódor, P.; Standovár, T.; Rozenbergar, D.; Diaci, J.; Wijdeven, S.M.J.; Meyer, P.; Winter, S.; Vrska, T.

    2005-01-01

    Data were analysed on the volume of dead wood in 86 beech forest reserves, covering most of the range of European beech forests. The mean volume was 130 m3/ha and the variation among reserves was high, ranging from almost nil to 550 m3/ha. The volume depended significantly on forest type, age since

  2. De novo transcriptome assembly and analysis of differential gene expression in response to drought in European beech.

    Directory of Open Access Journals (Sweden)

    Markus Müller

    Full Text Available Despite the ecological and economic importance of European beech (Fagus sylvatica L. genomic resources of this species are still limited. This hampers an understanding of the molecular basis of adaptation to stress. Since beech will most likely be threatened by the consequences of climate change, an understanding of adaptive processes to climate change-related drought stress is of major importance. Here, we used RNA-seq to provide the first drought stress-related transcriptome of beech. In a drought stress trial with beech saplings, 50 samples were taken for RNA extraction at five points in time during a soil desiccation experiment. De novo transcriptome assembly and analysis of differential gene expression revealed 44,335 contigs, and 662 differentially expressed genes between the stress and normally watered control group. Gene expression was specific to the different time points, and only five genes were significantly differentially expressed between the stress and control group on all five sampling days. GO term enrichment showed that mostly genes involved in lipid- and homeostasis-related processes were upregulated, whereas genes involved in oxidative stress response were downregulated in the stressed seedlings. This study gives first insights into the genomic drought stress response of European beech, and provides new genetic resources for adaptation research in this species.

  3. Forest Service's Northern Research Station FIA launches 24-state study of forest regeneration

    Science.gov (United States)

    Will McWilliams; Shawn Lehman; Paul Roth; Jim. Westfall

    2012-01-01

    Inventory foresters often quake when asked to count tree seedlings, because the work is tedious and sometimes means tallying hundreds of stems. They also know that the density and quality of advance regeneration are key to the success of new stand establishment. Seedling counts provide valuable information on regeneration adequacy, forest diversity, wildlife habitat,...

  4. Făgetele primare din România, o contribuţie la Patrimoniul Mondial UNESCO [Romania’s primary beech forests, a contribution to UNESCO World Heritage

    Directory of Open Access Journals (Sweden)

    Iovu Adrian Biriș

    2014-08-01

    Full Text Available The World Heritage List (WHL of UNESCO currently comprises 1007 properties in 161 States Parties. Most of these sites are cultural (779 and only 197 are natural sites whereas 31 are mixed sites with outstanding universal cultural and natural values. Romania has only 8 sites registered on WHL of UNESCO, 7 cultural sites and one natural site – The Danube Delta Biosphere Reserve - being underrepresented in relation with the real value of its natural patrimony. Beech is a deciduous species exclusively European and the beech forests constitute the potential natural vegetation for the temperate zone of Europe. Beech forests represent an outstanding and globally unparalleled example of the ongoing ecological processes of post-glacial expansion. This is a key factor for supporting the nomination of beech forests under WHL of UNESCO. Romania, the country with the larges area of beech forests and well preserved primary beech forests, has an important responsibility for the conservation of an adequate and representative network of beech forests. Considering these aspects, the Ministry of the Environment and Climate Change - Department for Waters, Forests and Fisheries, National Forest Administration – Romsilva, Forest Research and Management Institute, WWF Danube-Carpathian Programme Office and Greenpeace CEE Romania Foundation have signed a protocol for collaboration having as target the selection of certain beech forests to be included on the WHL of UNESCO. Keywords

  5. Ecological species group—Environmental factors relationships in unharvested beech forests in the north of Iran

    Science.gov (United States)

    Mohammad Naghi Adel; Hassan Pourbabaei; Daniel C. Dey

    2014-01-01

    Beech forests are the richest forest community in Iran because they are both economically and environmentally valuable. The greatest forest volume occurs in Iran's beech forests. Forests dominated by oriental beech (Fagus orientalis Lipskey) cover about 565,000 ha and represent the total area of indigenous forests in Guilan Province. A system for classifying beech...

  6. Use of microsatellite markers in an American beech (Fagus grandifolia) population and paternity testing

    Science.gov (United States)

    Jennifer Koch; Dave Carey; M.E. Mason

    2010-01-01

    Cross-species amplification of six microsatellite markers from European beech (Fagus sylvatica Linn) and nine markers from Japanese beech (Fagus crenata Blume) was tested in American beech (Fagus grandifolia Ehrh.). Three microsatellites from each species were successfully adapted for use in American beech...

  7. Comparisons of protein profiles of beech bark disease resistant and susceptible American beech (Fagus grandifolia)

    Science.gov (United States)

    2013-01-01

    Background Beech bark disease is an insect-fungus complex that damages and often kills American beech trees and has major ecological and economic impacts on forests of the northeastern United States and southeastern Canadian forests. The disease begins when exotic beech scale insects feed on the bark of trees, and is followed by infection of damaged bark tissues by one of the Neonectria species of fungi. Proteomic analysis was conducted of beech bark proteins from diseased trees and healthy trees in areas heavily infested with beech bark disease. All of the diseased trees had signs of Neonectria infection such as cankers or fruiting bodies. In previous tests reported elsewhere, all of the diseased trees were demonstrated to be susceptible to the scale insect and all of the healthy trees were demonstrated to be resistant to the scale insect. Sixteen trees were sampled from eight geographically isolated stands, the sample consisting of 10 healthy (scale-resistant) and 6 diseased/infested (scale-susceptible) trees. Results Proteins were extracted from each tree and analysed in triplicate by isoelectric focusing followed by denaturing gel electrophoresis. Gels were stained and protein spots identified and intensity quantified, then a statistical model was fit to identify significant differences between trees. A subset of BBD differential proteins were analysed by mass spectrometry and matched to known protein sequences for identification. Identified proteins had homology to stress, insect, and pathogen related proteins in other plant systems. Protein spots significantly different in diseased and healthy trees having no stand or disease-by-stand interaction effects were identified. Conclusions Further study of these proteins should help to understand processes critical to resistance to beech bark disease and to develop biomarkers for use in tree breeding programs and for the selection of resistant trees prior to or in early stages of BBD development in stands. Early

  8. Tree- and Stand-Level Thinning Effects on Growth of European Beech (Fagus sylvatica L. on a Northeast- and a Southwest-Facing Slope in Southwest Germany

    Directory of Open Access Journals (Sweden)

    Daniela Diaconu

    2015-09-01

    Full Text Available Anticipated changes in climate and research findings on the drought sensitivity of beech have triggered controversial discussions about the future of European beech. We investigated the growth response of beech on the tree- and stand-level in mature stands to three different thinning intensities (no thinning, strong thinning, very strong thinning on a northeast- and southwest-facing slope in Southwest Germany. Linear mixed-effects models were formulated to describe effects on growth parameters on the tree- and stand-level (diameter, height, basal area, volume. At the stand-level, the stand basal area increment and stand volume increment were lower on the thinned plots. At the tree-level, the basal area increment significantly increased with increasing thinning intensity. The growth of individual trees was also influenced by initial tree size, the size-related rank of the tree within a stand, and by the aspect of the site. Our data indicate that growth of European beech is impaired on the southwest-facing slope with a warmer and drier climate and that a very strong thinning regime applied at advanced age can accelerate growth of European beech trees even on the warmer and drier site. Our findings, therefore, imply that in a warmer climate intensive thinning may also represent an important adaptive forest management measure in European beech stands.

  9. Periodontal regeneration.

    Science.gov (United States)

    Ivanovski, S

    2009-09-01

    The ultimate goal of periodontal therapy is the regeneration of the tissues destroyed as a result of periodontal disease. Currently, two clinical techniques, based on the principles of "guided tissue regeneration" (GTR) or utilization of the biologically active agent "enamel matrix derivative" (EMD), can be used for the regeneration of intrabony and Class II mandibular furcation periodontal defects. In cases where additional support and space-making requirements are necessary, both of these procedures can be combined with a bone replacement graft. There is no evidence that the combined use of GTR and EMD results in superior clinical results compared to the use of each material in isolation. Great variability in clinical outcomes has been reported in relation to the use of both EMD and GTR, and these procedures can be generally considered to be unpredictable. Careful case selection and treatment planning, including consideration of patient, tooth, site and surgical factors, is required in order to optimize the outcomes of treatment. There are limited data available for the clinical effectiveness of other biologically active molecules, such as growth factors and platelet concentrates, and although promising results have been reported, further clinical trials are required in order to confirm their effectiveness. Current active areas of research are centred on tissue engineering and gene therapy strategies which may result in more predictable regenerative outcomes in the future.

  10. Height increment of beech and maple depending on the amount of incident light in the Badin primeval forest; Vyskovy prirastok buka a javora v zavislosti od mnozstva dopadajuceho svetla v pralese Badin

    Energy Technology Data Exchange (ETDEWEB)

    Havasova, M [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra regionalnej geografie, 84215 Bratislava (Slovakia)

    2012-04-25

    Processed study is devoted to a dependency of height increase of natural regeneration of beech and maple in Badin primeval forest . In selected site discontinuities there were chosen 2 tran-sects 1 m in width and oriented towards East - West and North - South, passing through the centre of the discontinuity. Heights of beech and maple individuals, as well as the rate of their annual increase (for 2010) were measured there. These data were then transformed to the values of reduced elevation gain. The amount of incident radiation was measured by hemispherical photographs, and we set the values of direct (DSF) and indirect sunlight (ISF). Globally, a negative effect of direct sunlight on the height growth of beech was shown. For height growth of maple no significant effect of different values of ISF or DFS was demonstrated, Justas well as no tran-sect orientation. Beech reached higher gains than maple. Overall bigger gains of the ground wood were achieved on the north side of the discontinuity. Height increment of beech and maple depending on the amount of incident light in the Badin primeval forest. (author)

  11. Mitochondrial DNA Unwinding Enzyme Required for Liver Regeneration | Center for Cancer Research

    Science.gov (United States)

    The liver has an exceptional capacity to proliferate. This ability allows the liver to regenerate its mass after partial surgical removal or injury and is the key to successful partial liver transplants. Liver cells, called hepatocytes, are packed with mitochondria, and regulating mitochondrial DNA (mtDNA) copy number is crucial to mitochondrial function, including energy production, during proliferation. Yves Pommier, M.D., Ph.D., of CCR’s Developmental Therapeutics Branch, and his colleagues recently showed that the vertebrate mitochondrial topoisomerase, Top1mt, was critical in maintaining mitochondrial function in the heart after doxorubicin-induced damage. The group wondered whether Top1mt might play a similar role in liver regeneration.

  12. Improving the utilization of beech sawdust by sheep

    International Nuclear Information System (INIS)

    Zelenak, I.; Boda, K.; Jalc, D.; Lenart, J.; Kmet, V.; Havassy, I.; Kosta, K.

    1991-01-01

    Defibration following treatment with 1% H 2 SO 4 as an impregnation agent increased the in vitro dry matter (DM) digestibility of beech sawdust to 59.5%. Digestibilities of barley straw, wheat straw, maize stover and bagasse were also increased through defibration without prior chemical treatment. Increased DM degradability was also reflected in better digestibility of fibre components and volatile fatty acids (VFA) production. The inclusion of treated beech sawdust in the diet at levels of up to 20% had no negative effect on lamb performance. Studies with 15 N labelled urea did not show clear positive effect on nitrogen utilization when sheep were fed the treated beech sawdust. Immobilized cellulase and the addition of branched-chain VFA significantly increased the in vitro degradation of treated beech sawdust. Methanol extract of treated beech sawdust had an inhibitory effect on the growth of Streptococus bovis and Lactobacillus plantarum and reduced in vitro fermentation of rumen fluid. (author). 15 refs, 3 figs, 10 tabs

  13. Screening for resistance to beech bark disease: Improvements and results from seedlings and grafted field selections

    Science.gov (United States)

    Jennifer L. Koch; Mary E. Mason; David W. Carey

    2012-01-01

    Beech bark disease (BBD) is an insect-disease complex that has been killing American beech (Fagus grandifolia Ehrh.) trees since the accidental introduction of the beech scale insect (Cryptococcus fagisuga) to Canada around 1890. Insect infestation is followed by infection with Neonectria ditissima or

  14. Development of molecular tools for use in beech bark disease management

    Science.gov (United States)

    Jennifer L. Koch; David W. Carey; Mary E. Mason; C. Dana Nelson; Abdelali Barakat; John E. Carlson; David. Neale

    2011-01-01

    Beech bark disease (BBD) has been killing American beech trees in eastern North America since the late 1890s. The disease is initiated by feeding of the beech scale insect, Cryptococcus fagisuga, which leads to the development of small fissures in the bark.

  15. Competition for nitrogen between European beech and sycamore maple shifts in favour of beech with decreasing light availability.

    Science.gov (United States)

    Simon, Judy; Li, Xiuyuan; Rennenberg, Heinz

    2014-01-01

    Plant species use different strategies for maximizing growth and fitness under changing environmental conditions. At the ecosystem level, seedlings in particular compete with other vegetation components for light and nitrogen (N), which often constitute growth-limiting resources. In this study, we investigated the effect of light availability on the competition for N between seedlings of European beech and sycamore maple and analysed the consequences of this competition for the composition of N metabolites in fine roots. Our results show different strategies in N acquisition between beech and sycamore maple. Both species responded to reduced light availability by adapting their morphological and physiological traits with a decrease in biomass and net assimilation rate and an increase in specific leaf area and leaf area ratio. For beech seedlings, competition with sycamore maple led to a reduction in organic N uptake capacity. Reduced light availability led to a decrease in ammonium, but an increase in glutamine-N uptake capacity in sycamore maple. However, this response was stronger compared with that of beech and was accompanied by reduced growth. Thus, our results suggest better adaptation of N acquisition to reduced light availability in beech compared with sycamore maple seedlings.

  16. Cryogenic regenerators

    International Nuclear Information System (INIS)

    Kush, P.; Joshi, S.C.; Thirumaleshwar, M.

    1986-01-01

    Importance of regenerators in cryogenic refrigerators is highlighted. Design aspects of regenerator are reviewed and the factors involved in the selection of regenerator material are enumerated. Various methods used to calculate the heat transfer coefficient and regenerator effectiveness are mentioned. Variation of effectiveness with various parameters is calculated by a computer programme using the ideal, Ackermann and Tipler formulae. Results are presented in graphical form. Listing of the computer programme is given in the Appendix. (author)

  17. Disintegration of beech wood char during thermal conversion

    DEFF Research Database (Denmark)

    Hindsgaul, Claus

    In the present work the processes occurring in the structures of slowly pyrolysed beech wood char during thermal gasification have been investigated. Emphasis was put on physical changes and gas transport properties during conversion. The highly anisotropic structure of wood was preserved in its ...

  18. Experimental Study on Dry Torrefaction of Beech Wood and Miscanthus

    Directory of Open Access Journals (Sweden)

    Eyerusalem M. Gucho

    2015-05-01

    Full Text Available Torrefaction is a thermochemical pre-treatment process for upgrading the properties of biomass to resemble those of fossil fuels such as coal. Biomass properties of particular interest are chemical composition, physical property and combustion characteristics. In this work, torrefaction of beech wood and miscanthus (sinensis was carried out to study the influence of torrefaction temperature (240–300 °C and residence time (15–150 min on the aforementioned properties of the biomass. Results of the study revealed that torrefaction temperature has a significant influence on mass and energy yields, whereas the influence of the residence time becomes more apparent for the higher torrefaction temperatures (>280 °C. Torrefied miscanthus resulted in higher energy densification compared to beech wood for a residence time of 30 min. A significant improvement in grindability of the torrefied beech wood was obtained even for lightly torrefied beech wood (at 280 °C and 15 min of residence time. Observation from the combustion study showed that the ignition temperature is slightly affected by the torrefaction temperature. As a whole, the torrefaction temperature determines the characteristics of the torrefied fuel compared to other process parameters like residence time. Furthermore, with optimal process conditions, torrefaction produces a solid fuel with combustion reactivity and porosity comparable to raw biomass, whereas grindability and heating value are comparable to low quality coal.

  19. Experimental Study on Dry Torrefaction of Beech Wood

    NARCIS (Netherlands)

    Gucho, Eyerusalem Merin; Shahzad, K.; Bramer, Eduard A.; Akhtar, N.A.; Brem, Gerrit

    2015-01-01

    Torrefaction is a thermochemical pre-treatment process for upgrading the properties of biomass to resemble those of fossil fuels such as coal. Biomass properties of particular interest are chemical composition, physical property and combustion characteristics. In this work, torrefaction of beech

  20. Present state of beech bark disease in Germany

    Science.gov (United States)

    Klaus J. Lang

    1983-01-01

    Beech bark disease can be found at present time in young and old stands (20-150 years old) of Fagus sylvatica. The present state of the disease may be described as "normal" and apart from some cases, it is no threat to the existence of the stands.

  1. Hot callusing for propagation of American beech by grafting

    Science.gov (United States)

    David W. Carey; Mary E. Mason; Paul Bloese; Jennifer L. Koch

    2013-01-01

    To increase grafting success rate, a hot callus grafting system was designed and implemented as part of a multiagency collaborative project to manage beech bark disease (BBD) through the establishment of regional BBD-resistant grafted seed orchards. Five years of data from over 2000 hot callus graft attempts were analyzed using a logistic regression model to determine...

  2. Soil base saturation combines with beech bark disease to influence composition and structure of sugar maple-beech forests in an acid rain-impacted region

    Science.gov (United States)

    Gregory B. Lawrence; Todd C. McDonnell; Timothy J. Sullivan; Martin Dovciak; Scott W. Bailey; Michael R. Antidormi; Michael R. Zarfos

    2017-01-01

    Sugar maple, an abundant and highly valued tree species in eastern North America, has experienced decline from soil calcium (Ca) depletion by acidic deposition, while beech, which often coexists with sugar maple, has been afflicted with beech bark disease (BBD) over the same period. To investigate how variations in soil base saturation combine with effects of BBD in...

  3. Vegetative regeneration

    Science.gov (United States)

    George A. Schier; John R. Jones; Robert P. Winokur

    1985-01-01

    Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

  4. Liver regeneration

    NARCIS (Netherlands)

    Chamuleau, R. A.; Bosman, D. K.

    1988-01-01

    Despite great advances in analysing hemodynamic, morphological and biochemical changes during the process of liver regeneration, the exact (patho)physiological mechanism is still unknown. A short survey of literature is given of the kinetics of liver regeneration and the significance of different

  5. Elastic and Strength Properties of Heat-Treated Beech and Birch Wood

    Directory of Open Access Journals (Sweden)

    Vlastimil Borůvka

    2018-04-01

    Full Text Available This paper deals with the impact of heat treatment on the elastic and strength properties of two diffuse porous hardwoods, namely Fagus sylvatica and Betula pendula. Two degrees of the heat treatment were used at temperatures of 165 °C and 210 °C. The dynamic and static elasticity modulus, bending strength, impact toughness, hardness, and density were tested. It is already known that an increase in treatment temperature decreases the mechanical properties and, on the other hand, leads to a better shape and dimensional stability. Higher temperatures of the heat treatment correlated with lower elastic and strength properties. In the case of higher temperature treatments, the decline of tested properties was noticeable as a result of serious changes in the chemical composition of wood. It was confirmed that at higher temperature stages of treatment, there was a more pronounced decrease in beech properties compared to those of the birch, which was the most evident in their bending strength and hardness. Our research confirmed that there is no reason to consider birch wood to be of a lesser quality, although it is regarded by foresters as an inferior tree species. After the heat treatment, the wood properties are almost the same as in the case of beech wood.

  6. SYNTAXOMOMICAL SURVEY O F EUROPEAN BEECH FORESTS: SOME GENERAL CONCLUSIONS

    Directory of Open Access Journals (Sweden)

    H. DIERSCHKE

    1997-01-01

    Full Text Available A short overwiev is given about the historical development of syntaxonomy of European beech forests. Different solutions of classification have been proposed, following more or less two main approaches: Division of alliances and suballiances by ecologically or geographically orientated species groups. A new classification of European beech forests is proposed with 8 (or more geographically orientated alliances, which can be further divided into suballiances by ecological species groups. For each alliance character and differential species, nomenclatural type and the area is mentioned, based on a (non puplished synthetic table, including 10.006 relevés from all parts of Europe. From this table also some overlapping species groups (a-n are given.

  7. Flux-profile relationships over a fetch limited beech forest

    DEFF Research Database (Denmark)

    Dellwik, E.; Jensen, N.O.

    2005-01-01

    The influence of an internal boundary layer and a roughness sublayer on flux-profile relationships for momentum and sensible heat have been investigated for a closed beech forest canopy with limited fetch conditions. The influence was quantified by derivation of local scaling functions for sensible...... heat flux and momentum (phi(h) and phi(m)) and analysed as a function of atmospheric stability and fetch. For heat, the influences of the roughness sublayer and the internal boundary layer were in agreement with previous studies. For momentum, the strong vertical gradient of the flow just above...... the canopy top for some wind sectors led to an increase in phi(m), a feature that has not previously been observed. For a fetch of 500 m over the beech forest during neutral atmospheric conditions, there is no height range at the site where profiles can be expected to be logarithmic with respect to the local...

  8. China's Beech Forests in the Pre-Quaternary

    Directory of Open Access Journals (Sweden)

    L. Yu-Sheng

    1998-01-01

    Full Text Available Fagus in China is never dominant in Late Cretaceous and Tertiary floras although it might reach its highest diversity in the Miocene. The genus Fagus was more widely distributed during the Palaeogene than in the Neogene. Furthermore, the ecological requirements of Fagus in the Palaeogene seem much broader than those in the Neogene onwards. This is because the Palaeogene floras containing Fagus lived in various conditions from an arid and hot climate to a humid and warm habitat. Additionally, Fagus then coexisted with many kinds of hygrophilous, thermophilous and xerophilous plants. However, the wide distribution, broad ecological adaptation and species composition changed greatly in the Neogene. The Neogene Fagus-containing floras are slightly more similar to the modern beech forests than the Palaeogene ones, although a big difference remains. Chinese fossil data document the post-Tertiary development of the modern beech forests. doi:10.1002/mmng.19980010111

  9. Beech cupules as keystone structures for soil fauna.

    Science.gov (United States)

    Melguizo-Ruiz, Nereida; Jiménez-Navarro, Gerardo; Moya-Laraño, Jordi

    2016-01-01

    Facilitative or positive interactions are ubiquitous in nature and play a fundamental role in the configuration of ecological communities. In particular, habitat modification and niche construction, in which one organism locally modifies abiotic conditions and favours other organisms by buffering the effects of adverse environmental factors, are among the most relevant facilitative interactions. In line with this, 'keystone structures', which provide resources, refuge, or advantageous services decisive for other species, may allow the coexistence of various species and thus considerably contribute to diversity maintenance. Beech cupules are woody husks harbouring beech fruits that remain in the forest soil for relatively long periods of time. In this study, we explored the potential role of these cupules in the distribution and maintenance of the soil fauna inhabiting the leaf litter layer. We experimentally manipulated cupule availability and soil moisture in the field to determine if such structures are limiting and can provide moist shelter to soil animals during drought periods, contributing to minimize desiccation risks. We measured invertebrate abundances inside relative to outside the cupules, total abundances in the leaf litter and animal body sizes, in both dry and wet experimental plots. We found that these structures are preferentially used by the most abundant groups of smaller soil animals-springtails, mites and enchytraeids-during droughts. Moreover, beech cupules can be limiting, as an increase in use was found with higher cupule densities, and are important resources for many small soil invertebrates, driving the spatial structure of the soil community and promoting higher densities in the leaf litter, probably through an increase in habitat heterogeneity. We propose that fruit woody structures should be considered 'keystone structures' that contribute to soil community maintenance. Therefore, beech trees may indirectly facilitate soil fauna

  10. THE QUALITY OF THE SURFACE AT THE BEECH WOODTURNING

    Directory of Open Access Journals (Sweden)

    Mirela CHERCIU

    2015-05-01

    Full Text Available There have been experiments made with outside cylindrical beech woodturning with low cutting speed, and feed successively changed. We study, qualitative rather than quantitative, the roughnesss of the surface achieved. It interprets the appearance of each surface based on the theory of cutting considerations. Resulted surface images are given, photographed with a camera and microscope. It appears that here are no propellers generated by the cutting tool nose on the cylindrical part, excepting the situation of using high feeds.

  11. Effect of a long-term afforestation of pine in a beech domain in NE-Spain revealed by analytical pyrolysis (Py-GC/MS)

    Science.gov (United States)

    Girona García, Antonio; Badía-Villas, David; Tomás Jiménez-Morillo, Nicasio; Martí-Dalmau, Clara; González-Pérez, José Antonio

    2015-04-01

    The replacement of native beech forests (Fagus sylvatica) by Scots pine (Pinus sylvestris) afforestation may exert changes in soil properties, particularly in soil organic matter (SOM) [1]. It is known that the products generated by Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) pyrolysis of organic matter are related to their origin [2 and references therein]. Therefore this technique can be used to investigate said changes. In this work, Py-GC/MS is used to study changes in SOM quality surrogated to the effect of the centennial replacement of beech by Scots pine. The soils studied were two acid soil profiles developed on quartzites under a humid climate at an altitude of 1400-1500 masl from Moncayo (Iberian range, NE-Spain). For each soil profile three organic layers (litter: OL, fragmented litter OF and humified litter OH) and the mineral soil horizons (Ah, E, Bhs and C) were sampled. After 100 years since the pine afforestation, differences in the relative abundance of lipids released by pyrolysis were observed in the O-layers ranging from 3.82-7.20% in pine soils and 0.98-1.25% in beech soils. No differences were observed in mineral horizons with depth except for the C horizons where beech lipid content was much higher (21.25%) than in that under pine (1.07%). Both pine and beech soils show similar nitrogen compounds relative contents along the soil profile, increasing from OL to Ah (3.49-9.11% and 2.75-11.73% in beech and pine respectively) with a conspicuous reduction in the E horizon. It is remarkable the absence of nitrogen compounds in beech Bhs and C horizons. The relative content of aromatic compounds in O-layers show opposite trends for beech and pine; an enrichment in aromatic compounds is observed in beech OL layer (12.39%) decreasing to 4.11% in OH layer in contrast, whereas for pine O-layers the aromatic compounds relative abundance was higher in the OH (5.83%) than in the OL layer (2.8%). Mineral Ah and E horizons show similar values in

  12. Researching the Possibility of Creating Highly Effective Catalysts for the Thermochemical Heat Regeneration and Hydrocarbon Reforming

    Science.gov (United States)

    2006-11-01

    interest get researches on replacement of granular carriers on a basis aluminium oxide by metals and their alloys in the form of fibres , metal tapes...applied to the alloys with non-equilibrium structure, it was established that the following properties have the most significant impact upon this process... Usage of metallic backings such as, i.g., alloy of the grades X20H80, X18H10T or X15Ю5 require thorough surface treatment and a special technology

  13. Ecological species group—Environmental factors relationships in unharvested beech forests in the north of Iran

    Science.gov (United States)

    Mohammad Naghi Adel; Hassan Pourbabaei; Daniel C. Dey

    2014-01-01

    Beech forests are the richest forest community in Iran because they are both economically and environmentally valuable. The greatest forest volume occurs in Iran's beech forests. Forests dominated by oriental beech (Fagus orientalis Lipskey) cover about 565,000 ha and represent the total area of indigenous forests in Guilan Province. A system...

  14. Litter quality effects of beech and hornbeam on undergrowth species diversity in Luxembourg forests on limestone and decalcified marl

    NARCIS (Netherlands)

    Kooijman, A.M.

    2010-01-01

    Question: Do beech and hornbeam differ in undergrowth species diversity, and could these differences be explained by mass of the organic layer, pH or soil moisture? Could species richness under beech and hornbeam be explained by differences in N dynamics? Location: Ancient forests dominated by beech

  15. Selective bark-stripping of beech, Fagus sylvatica, by free-ranging horses

    NARCIS (Netherlands)

    Kuiters, A.T.; Sluijs, van der L.A.M.; Wytema, G.A.

    2006-01-01

    Incidence and intensity of bark-stripping by horses was surveyed in stands and tree lanes of European beech (Fagus sylvatica L.) in Veluwezoom National Park, by using transects. Damage was apparent on 38% of beech trees, and 11% were seriously damaged (score 3 or more). Susceptibility to

  16. Wood and bark anatomy of young beech in relation to Cryptococcus attack

    Science.gov (United States)

    David. Lonsdale

    1983-01-01

    Within a sample of European beech, partial resistance to attack by the beech scale, Cryptococcus fagisuga, was associated with a smooth bark which had a regular, vertical pattern in its surface 'growth lines'. Such bark contained relatively little lignified outer parenchyma, and the main stone cell layer was strongly developed. The '...

  17. Timely salvage can reduce losses from beech scale-Nectria attack

    Science.gov (United States)

    David Crosby; J. C. Bjorkbom

    1958-01-01

    Beech is one of our more common hardwoods. It is an important component of the northern hardwood forest type, which occupies about 29 percent of the commercial forest land in the New England and Middle Atlantic States. In terms of total sawtimber volume, beech follows close on sugar maple, red oak, and yellow birch. It is used for a variety of products such as...

  18. Arthropod diversity in pristine vs. managed beech forests in Transcarpathia (Western Ukraine

    Directory of Open Access Journals (Sweden)

    Vasyl Chumak

    2015-01-01

    We conclude that biodiversity in pristine beech forests is not generally higher than in managed beech forests. However, the much higher amount of dead wood in pristine forests provides a source habitat for saproxylic species spreading into managed forest plots in the same region, but not to distant forests, far from virgin forests, such as in Western Europe.

  19. Major characteristics of mixed fir and beech virgin forests in the National park Biogradska Gora in Montenegro

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    Čurović Milić

    2011-01-01

    Full Text Available In order to manage forest ecosystems at a sufficiently high biodiversity level it is necessary to study the ecological, structural and production characteristics of virgin forests. The research was directed towards identifying the characteristics of mixed fir and beech forests (Abieti-Fagetum s. lat. in the area of the strict reserve of the National Park Biogradska Gora in Montenegro. Basic characteristics of these forests were researched in the process of definition of forest types. In this manner, it is for the first time that a realistic base for typological management of forests and forest ecosystems with similar ecological and structural characteristics was provided for the specific sites.

  20. Factors impacting stemflow generation in a European beech forest: Individual tree versus neighborhood properties

    Science.gov (United States)

    Metzger, Johanna Clara; Germer, Sonja; Hildebrandt, Anke

    2017-04-01

    The redistribution of precipitation by canopies changes the water flow dynamics to the forest floor. The spatial pattern of throughfall has been researched in a number of studies in different ecosystems. Yet, also stemflow substantially influences water input patterns, constituting a mean of 12% of gross precipitation for European beech as one of the most abundant tree species in Central Europe. While the initiation of stemflow depends mostly on precipitation event properties, stemflow amounts are strongly shaped by canopy structure. Stemflow research has mainly addressed the impact of single tree morphological variables. In previous studies, the impact of forest structure on area-based stemflow was studied comparing plots with different properties using few exemplary stemflow measurements. In non-homogeneous stands, this approach might not be accurate, as the variation of stand properties like tree density could change tree individual stemflow fluxes. To investigate this, a total measurement of all trees per plot is required. We hypothesize, that in addition to individual tree metrics, tree neighborhood relations have a significant impact on stemflow generation in a heterogeneous beech forest. Our study site is located in the pristine forest of the National Park Hainich, central Germany. It is heterogeneous in respect to tree density, species composition and tree age. We measured stemflow in an areal approach, for all trees on 11 subplots (each 10 m x 10 m) spaced evenly throughout a 1 ha plot. This involved overall 65 trees, which is 11% of the plot's trees. 27 precipitation events were recorded in spring and early summer of 2015 and 2016. Stand properties were surveyed, including diameter at breast height, height, position and species of a tree. From this data, we calculated neighborhood properties for each tree, as number, basal area, and relative height of neighboring trees within a radius of the plot's mean tree distance. Using linear mixed effects models, we

  1. Intra-specific variations in expression of stress-related genes in beech progenies are stronger than drought-induced responses.

    Science.gov (United States)

    Carsjens, Caroline; Nguyen Ngoc, Quynh; Guzy, Jonas; Knutzen, Florian; Meier, Ina Christin; Müller, Markus; Finkeldey, Reiner; Leuschner, Christoph; Polle, Andrea

    2014-12-01

    Rapidly decreasing water availability as a consequence of climate change is likely to endanger the range of long-lived tree species. A pressing question is, therefore, whether adaptation to drought exists in important temperate tree species like European beech (Fagus sylvatica L.), a wide-spread, dominant forest tree in Central Europe. Here, five beech stands were selected along a precipitation gradient from moist to dry conditions. Neutral genetic markers revealed strong variation within and little differentiation between the populations. Natural regeneration from these stands was transferred to a common garden and used to investigate the expression of genes for abscisic acid (ABA)-related drought signaling [9-cis-epoxy-dioxygenase (NCED), protein phosphatase 2C (PP2C), early responsive to dehydration (ERD)] and stress protection [ascorbate peroxidase (APX), superoxide dismutase (SOD), aldehyde dehydrogenase (ALDH), glutamine amidotransferase (GAT)] that are involved in drought acclimation. We hypothesized that progenies from dry sites exhibit constitutively higher expression levels of ABA- and stress-related genes and are less drought responsive than progenies from moist sites. Transcript levels and stress responses (leaf area loss, membrane integrity) of well-irrigated and drought-stressed plants were measured during the early, mid- and late growing season. Principal component (PC) analysis ordered the beech progenies according to the mean annual precipitation at tree origin by the transcript levels of SOD, ALDH, GAT and ERD as major loadings along PC1. PC2 separated moist and drought treatments with PP2C levels as important loading. These results suggest that phosphatase-mediated signaling is flexibly acclimated to the current requirements, whereas stress compensatory measures exhibited genotypic variation, apparently underlying climate selection. In contrast to expectation, the drought responses were less pronounced than the progeny-related differences and the

  2. Space sequestration below ground in old-growth spruce-beech forests-signs for facilitation?

    Science.gov (United States)

    Bolte, Andreas; Kampf, Friederike; Hilbrig, Lutz

    2013-01-01

    Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤2 mm) by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1) spruce as a central tree, (2) spruce as competitor, (3) beech as a central tree, and (4) beech as competitor. Mean values of life fine root attributes like biomass (FRB), length (FRL), and root area index (RAI) were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA) exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL) and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA), asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area.

  3. Space sequestration below ground in old-growth spruce-beech forests – signs for facilitation?

    Directory of Open Access Journals (Sweden)

    Andreas eBolte

    2013-08-01

    Full Text Available Scientists are currently debating the effects of mixing tree species for the complementary resource acquisition in forest ecosystems. In four unmanaged old-growth spruce-beech forests in strict nature reserves in southern Sweden and northern Germany we assessed forest structure and fine rooting profiles and traits (≤ 2 mm by fine root sampling and the analysis of fine root morphology and biomass. These studies were conducted in selected tree groups with four different interspecific competition perspectives: (1 spruce as a central tree, (2 spruce as competitor, (3 beech as a central tree, and (4 beech as competitor. Mean values of life fine root attributes like biomass (FRB, length (FRL, and root area index (RAI were significantly lower for spruce than for beech in mixed stands. Vertical profiles of fine root attributes adjusted to one unit of basal area (BA exhibited partial root system stratification when central beech is growing with spruce competitors. In this constellation, beech was able to raise its specific root length (SRL and therefore soil exploration efficiency in the subsoil, while increasing root biomass partitioning into deeper soil layers. According to relative values of fine root attributes (rFRA, asymmetric below-ground competition was observed favoring beech over spruce, in particular when central beech trees are admixed with spruce competitors. We conclude that beech fine rooting is facilitated in the presence of spruce by lowering competitive pressure compared to intraspecific competition whereas the competitive pressure for spruce is increased by beech admixture. Our findings underline the need of spatially differentiated approaches to assess interspecific competition below ground. Single-tree approaches and simulations of below-ground competition are required to focus rather on microsites populated by tree specimens as the basic spatial study area.

  4. Characteristics of the soil in mountain beech communities on mountain Manjača

    Directory of Open Access Journals (Sweden)

    Eremija Saša

    2008-01-01

    Full Text Available The presented results of soil study, which will be used for defining the beech forest types of management unit 'Dubička Gora' on Mt. Manjača, are the basis for solving a series of current tasks of forestry profession. Relief and chemical nature of limestone are the main factors of the soil cover differentiation (Knežević, Košanin, 2004.. The results of physical and chemical soil properties are shown and its taxonomy is determined. Forest cover is represented by heterogeneous units-forest combinations. Four basic soil types are defined on the basis of detailed field and laboratory research: rendzina on dolomite, chernozem on limestone, brown soil on limestone, illimerised soil on limestone and dolomite.

  5. Natural radiation dose of small mammalians in beech forest of Rokkasho, Japan

    International Nuclear Information System (INIS)

    Ohtsuka, Yoshihito; Iyogi, Takashi; Takaku, Yuichi; Hisamatsu, Shun'ichi

    2008-01-01

    Full text: Protection of the environment itself from radiation hazards is recognized as important as that of humans. Actual data on the background natural radiation dose, which is necessary to evaluate the effect of radiation, are very few, especially in the terrestrial environment. Forests around the Japan's first large scale nuclear fuel reprocessing plant in Rokkasho were selected as the research field for evaluating the background natural radiation to the environment. Data observed will be used in future for the comparison with the radiation dose from radionuclides released from the plant. Small mammalians, mouse (Apodeums argentus) and mole (Urotrichus talpoides), were selected as representative animals of the forests in this study, and it was planned to measure their radiation doses from natural sources; environmental γ-rays, Rn and internal radionuclides. The forests around the plant were classified into three types: beech, oak and coniferous. We have been measuring the natural radiation to the mammalians in each of those forests one by one and report the data for the beech forest here. The mammalians caught in traps in the beech forest during June-October, 2006 were analyzed for their natural radionuclides burdens ( 210 Pb, 210 Po, 40 K, 87 Rb, 226 Ra, 238 U and 232 Th) in 11 organs and carcass. Radiation dose rates from environmental γ-rays and atmospheric concentration of Rn in the forest were also measured during August-December, 2006. Mean internal dose rates of mouse and mole caught in June, 2006 were estimated to be 0.036 μGy h -1 and 0.28 μGy h -1 , respectively, from mean concentrations of the nuclides in a total body and internal dose conversion coefficients by FASSET. The difference of the dose between the two mammalian species was attributed to higher contribution of 210 Po in mole, in which dose reached 0.25 μGy h -1 in contrast to that in mouse of 0.016 μGy h -1 . The concentration of 210 Po in kidney of mole (0.37 Bq g -1 wet) was

  6. My Regeneration:

    DEFF Research Database (Denmark)

    Carter, Dale

    2017-01-01

    and cultural referents shows that it offers an index to the album. Using its frontier setting and a variety of sacred and secular myths, symbols and icons, ‘Heroes and Villains,’ like Smile as a whole, offers historically-informed visions of national decline, crisis and regeneration that are at once critical...

  7. The neglected bee trees: European beech forests as a home for feral honey bee colonies

    Directory of Open Access Journals (Sweden)

    Patrick Laurenz Kohl

    2018-04-01

    Full Text Available It is a common belief that feral honey bee colonies (Apis mellifera L. were eradicated in Europe through the loss of habitats, domestication by man and spread of pathogens and parasites. Interestingly, no scientific data are available, neither about the past nor the present status of naturally nesting honeybee colonies. We expected near-natural beech (Fagus sylvatica L. forests to provide enough suitable nest sites to be a home for feral honey bee colonies in Europe. Here, we made a first assessment of their occurrence and density in two German woodland areas based on two methods, the tracing of nest sites based on forager flight routes (beelining technique, and the direct inspection of potential cavity trees. Further, we established experimental swarms at forest edges and decoded dances for nest sites performed by scout bees in order to study how far swarms from beekeeper-managed hives would potentially move into a forest. We found that feral honey bee colonies regularly inhabit tree cavities in near-natural beech forests at densities of at least 0.11–0.14 colonies/km2. Colonies were not confined to the forest edges; they were also living deep inside the forests. We estimated a median distance of 2,600 m from the bee trees to the next apiaries, while scout bees in experimental swarms communicated nest sites in close distances (median: 470 m. We extrapolate that there are several thousand feral honey bee colonies in German woodlands. These have to be taken in account when assessing the role of forest areas in providing pollination services to the surrounding land, and their occurrence has implications for the species’ perception among researchers, beekeepers and conservationists. This study provides a starting point for investigating the life-histories and the ecological interactions of honey bees in temperate European forest environments.

  8. The neglected bee trees: European beech forests as a home for feral honey bee colonies.

    Science.gov (United States)

    Kohl, Patrick Laurenz; Rutschmann, Benjamin

    2018-01-01

    It is a common belief that feral honey bee colonies ( Apis mellifera L.) were eradicated in Europe through the loss of habitats, domestication by man and spread of pathogens and parasites. Interestingly, no scientific data are available, neither about the past nor the present status of naturally nesting honeybee colonies. We expected near-natural beech ( Fagus sylvatica L.) forests to provide enough suitable nest sites to be a home for feral honey bee colonies in Europe. Here, we made a first assessment of their occurrence and density in two German woodland areas based on two methods, the tracing of nest sites based on forager flight routes (beelining technique), and the direct inspection of potential cavity trees. Further, we established experimental swarms at forest edges and decoded dances for nest sites performed by scout bees in order to study how far swarms from beekeeper-managed hives would potentially move into a forest. We found that feral honey bee colonies regularly inhabit tree cavities in near-natural beech forests at densities of at least 0.11-0.14 colonies/km 2 . Colonies were not confined to the forest edges; they were also living deep inside the forests. We estimated a median distance of 2,600 m from the bee trees to the next apiaries, while scout bees in experimental swarms communicated nest sites in close distances (median: 470 m). We extrapolate that there are several thousand feral honey bee colonies in German woodlands. These have to be taken in account when assessing the role of forest areas in providing pollination services to the surrounding land, and their occurrence has implications for the species' perception among researchers, beekeepers and conservationists. This study provides a starting point for investigating the life-histories and the ecological interactions of honey bees in temperate European forest environments.

  9. The influence of seedling density in containers on morphological characteristics of European beech

    Directory of Open Access Journals (Sweden)

    Wrzesiński Piotr

    2015-09-01

    Full Text Available This study examines the influence on growth parameters, in particular the morphological features of the root system, of 1-year-old European beech seedlings cultivated in containers with two different densities. The experiment was conducted in the container nursery in Skierdy (Forest District of Jabłonna in spring 2011. After 10 months of cultivation in Hiko polyethylene containers, above- and below-ground parts of the seedlings were measured. The measurements of the root system were conducted with a scanner and the WinRHIZO software. No influence due to the seedling density on either shoot height or thickness was observed, but instead the research showed that different seedling densities affected the development of root systems. The mean root thickness and dry mass of the European beech seedlings were significantly higher at the lower density. The influence of seedling density on the development of root mass deserves special attention as it is the most important factor affecting future growth of the seedlings during cultivation. This tendency also suggests that the amount of nutrients allocated to shoot development may be higher in order to improve the efficiency of photosynthesis. At both densities, differences in biomass accumulation affected the root-toshoot ratio. In seedlings cultivated at the lower density, the increased dry root matter of the seedlings resulted in a significant increase in the root-to-shoot ratio. This may cause a potential growth advantage of these seedlings after they are planted and may thus result in a more productive cultivation.

  10. Safeguarding saproxylic fungal biodiversity in Apennine beech forest priority habitats

    Science.gov (United States)

    Maggi, Oriana; Lunghini, Dario; Pecoraro, Lorenzo; Sabatini, Francesco Maria; Persiani, Anna Maria

    2015-04-01

    The FAGUS LIFE Project (LIFE11/NAT/IT/135) targets two European priority habitats, i.e. Habitat 9210* Apennine beech forests with Taxus and Ilex, and Habitat 9220* Apennine beech forests with Abies alba, within two National Parks: Cilento, Vallo di Diano and Alburni; Gran Sasso and Monti della Laga. The current limited distribution of the target habitats is also due to the impact of human activities on forest systems, such as harvesting and grazing. The FAGUS project aims at developing and testing management strategies able to integrate the conservation of priority forest habitats (9210* and 9220*) and the sustainable use of forest resources. In order to assess the responses to different management treatments the BACI monitoring design (Before-After, Control-Intervention) has been applied on forest structure and diversity of focus taxa before and after experimental harvesting treatments. Conventional management of Apennine beech forests impacts a wealth of taxonomic groups, such as saproxylic beetles and fungi, which are threatened throughout Europe by the lack of deadwood and of senescing trees, and by the homogeneous structure of managed forests. Deadwood has been denoted as the most important manageable habitat for biodiversity in forests not only for supporting a wide diversity of organisms, but also for playing a prominent role in several ecological processes, creating the basis for the cycling of photosynthetic energy, carbon, and nutrients stored in woody material. Especially fungi can be regarded as key group for understanding and managing biodiversity associated with decaying wood. The before-intervention field sampling was carried out in Autumn 2013 in 33 monitoring plots across the two national Parks. The occurrence at plot level of both Ascomycota and Basidiomycota sporocarps was surveyed. All standing and downed deadwood with a minimum diameter of 10 cm was sampled for sporocarps larger than 1 mm, and information on decay class and fungal morphogroups

  11. Competition for nitrogen sources between European beech (Fagus sylvatica) and sycamore maple (Acer pseudoplatanus) seedlings.

    Science.gov (United States)

    Simon, J; Waldhecker, P; Brüggemann, N; Rennenberg, H

    2010-05-01

    To investigate the short-term consequences of direct competition between beech and sycamore maple on root N uptake and N composition, mycorrhizal seedlings of both tree species were incubated for 4 days (i.e. beech only, sycamore maple only or both together) in an artificial nutrient solution with low N availability. On the fourth day, N uptake experiments were conducted to study the effects of competition on inorganic and organic N uptake. For this purpose, multiple N sources were applied with a single label. Furthermore, fine roots were sampled and analysed for total amino acids, soluble protein, total nitrogen, nitrate and ammonium content. Our results clearly show that both tree species were able to use inorganic and organic N sources. Uptake of inorganic and organic N by beech roots was negatively affected in the presence of the competing tree species. In contrast, the presence of beech stimulated inorganic N uptake by sycamore maple roots. Both the negative effect of sycamore maple on N uptake of beech and the positive effect of beech on N uptake of sycamore maple led to an increase in root soluble protein in beech, despite an overall decrease in total N concentration. Thus, beech compensated for the negative effects of the tree competitor on N uptake by incorporating less N into structural N components, but otherwise exhibited the same strategy as the competitor, namely, enhancing soluble protein levels in roots when grown under competition. It is speculated that enhanced enzyme activities of so far unknown nature are required in beech as a defence response to inter-specific competition.

  12. Similar net ecosystem exchange of beech stands located in France and Denmark

    DEFF Research Database (Denmark)

    Granier, A.; Pilegaard, K.; Jensen, N.O.

    2002-01-01

    Net ecosystem exchange (NEE), as measured with eddy covariance was compared for two European beech stands for the years 1996-1999: a young beech forest (32 year-old) growing in east France, and a mature beech stand (80 year-old) located in Denmark. Those sites are included in the Carboeuroflux....../Carbodata European networks. Except for some short-term differences (1-5 days), the temporal variation of NEE followed similar patterns in both sites. This similarity followed from similar values of. (i) dates of bud break and of leaf fall; (ii) ecosystem respiration rates during winter; (iii) diurnal NEE during...

  13. Cultural treatments and woody debris: the study case of beech forests in Casentino (Italy

    Directory of Open Access Journals (Sweden)

    Calamini G

    2009-01-01

    Full Text Available This paper shows the first results about quantity and quality of dead wood on the ground in beech forests of Foreste Casentinesi, Monte Falterona and Campigna National Park. The presence of dead wood depends on several factors such as forest productivity, natural disturbances and human activities. Data from some mature managed beech stands have been collected and compared with those from unmanaged beech forest (Sasso Fratino full-protected Reserve. Results do not show significant differences between managed and unmanaged forests. The dead wood varies between 5 and 8 Mg ha-1 (in terms of total dry weight mostly composed by fine woody debris.

  14. Research and Education of CO{sub 2} Separation from Coal Combustion Flue Gases with Regenerable Magnesium Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo-Youp

    2013-09-30

    A novel method using environment-friendly chemical magnesium hydroxide (Mg(OH){sub 2}) solution to capture carbon dioxide from coal-fired power plants flue gas has been studied under this project in the post-combustion control area. The project utilizes the chemistry underlying the CO{sub 2}-Mg(OH){sub 2} system and proven and well-studied mass transfer devices for high levels of CO{sub 2} removal. The major goals of this research were to select and design an appropriate absorber which can absorb greater than 90% CO{sub 2} gas with low energy costs, and to find and optimize the operating conditions for the regeneration step. During the project period, we studied the physical and chemical characteristics of the scrubbing agent, the reaction taking place in the system, development and evaluation of CO{sub 2} gas absorber, desorption mechanism, and operation and optimization of continuous operation. Both batch and continuous operations were performed to examine the effects of various parameters including liquid-to-gas ratio, residence time, lean solvent concentration, pressure drop, bed height, CO{sub 2} partial pressure, bubble size, pH, and temperature on the absorption. The dissolution of Mg(OH){sub 2} particles, formation of magnesium carbonate (MgCO{sub 3}), and vapor-liquid-solid equilibrium (VLSE) of the system were also studied. The dissolution of Mg(OH){sub 2} particles and the steady release of magnesium ions into the solution was a crucial step to maintain a level of alkalinity in the CO{sub 2} absorption process. The dissolution process was modeled using a shrinking core model, and the dissolution reaction between proton ions and Mg(OH){sub 2} particles was found to be a rate-controlling step. The intrinsic surface reaction kinetics was found to be a strong function of temperature, and its kinetic expression was obtained. The kinetics of MgCO{sub 3} formation was also studied in terms of different pH values and temperatures, and was enhanced under high p

  15. Skeletal muscle regeneration is modulated by inflammation

    Directory of Open Access Journals (Sweden)

    Wenjun Yang

    2018-04-01

    Full Text Available Skeletal muscle regeneration is a complex process orchestrated by multiple steps. Recent findings indicate that inflammatory responses could play central roles in bridging initial muscle injury responses and timely muscle injury reparation. The various types of immune cells and cytokines have crucial roles in muscle regeneration process. In this review, we briefly summarise the functions of acute inflammation in muscle regeneration. The translational potential of this article: Immune system is closely relevant to the muscle regeneration. Understanding the mechanisms of inflammation in muscle regeneration is therefore critical for the development of effective regenerative, and therapeutic strategies in muscular disorders. This review provides information for muscle regeneration research regarding the effects of inflammation on muscle regeneration. Keywords: Chronic muscle disorders, Cytokines, Immune cells, Inflammation, Muscle regeneration, Muscle stem cells

  16. Research into the Effect of Supercapacitor Terminal Voltage on Regenerative Suspension Energy-Regeneration and Dynamic Performance

    Directory of Open Access Journals (Sweden)

    Ruochen Wang

    2017-01-01

    Full Text Available To study the effect of supercapacitor initial terminal voltage on the regenerative and semiactive suspension energy-regeneration and dynamic performance, firstly, the relationship between supercapacitor terminal voltage and linear motor electromagnetic damping force and that between supercapacitor terminal voltage and recycled energy by the supercapacitor in one single switching period were both analyzed. The result shows that the linear motor electromagnetic damping force is irrelevant to the supercapacitor terminal voltage, and the recycled energy by the supercapacitor reaches the maximum when initial terminal voltage of the supercapacitor equals output terminal voltage of the linear motor. Then, performances of system dynamics and energy-regeneration were studied as the supercapacitor initial terminal voltage varied in situations of B level and C level road. The result showed that recycled energy by the supercapacitor increased at first and then decreased while the dynamic performance had no obvious change. On the basis of previous study, a mode-switching control strategy of supercapacitor for the regenerative and semiactive suspension system was proposed, and the mode-switching rule was built. According to simulation and experiment results, the system energy-regeneration efficiency can be increased by utilizing the control strategy without influencing suspension dynamic performance, which is highly valuable to practical engineering.

  17. Species richness pattern along altitudinal gradient in Central European beech forests

    Czech Academy of Sciences Publication Activity Database

    Hrivnák, R.; Gömöry, D.; Slezák, M.; Ujházy, K.; Hédl, Radim; Jarčuška, B.; Ujházyová, M.

    2014-01-01

    Roč. 49, č. 3 (2014), s. 425-441 ISSN 1211-9520 Institutional support: RVO:67985939 Keywords : altitude * beech-dominated forest * species richness Subject RIV: EF - Botanics Impact factor: 1.778, year: 2014

  18. Investigation of beech wood modified by radio-frequency discharge plasma

    Czech Academy of Sciences Publication Activity Database

    Novák, I.; Popelka, A.; Špitalský, Z.; Mičušík, M.; Omastová, M.; Valentin, M.; Sedliačik, J.; Janigová, I.; Kleinová, A.; Šlouf, Miroslav

    2015-01-01

    Roč. 119, September (2015), s. 88-94 ISSN 0042-207X Institutional support: RVO:61389013 Keywords : radio-frequency plasma * beech wood * adhesive properties Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.558, year: 2015

  19. Partitioning of ecosystem respiration in a beech forest

    DEFF Research Database (Denmark)

    Brændholt, Andreas; Ibrom, Andreas; Larsen, Klaus Steenberg

    2018-01-01

    Terrestrial ecosystem respiration (Reco) represents a major component of the global carbon cycle. It consists of many sub-components, such as aboveground plant respiration and belowground root and microbial respiration, each of which may respond differently to abiotic factors, and thus to global...... of Reco in a temperate beech forest at diel, seasonal and annual time scales. Reco was measured by eddy covariance while respiration rates from soil, tree stems and isolated coarse tree roots were measured bi-hourly by an automated closed-chamber system. Soil respiration (Rsoil) was measured in intact...... plots, and heterotrophic Rsoil was measured in trenched plots. Tree stem (Rstem) and coarse root (Rroot) respiration were measured by custom made closed-chambers. We found that the contribution of Rstem to total Reco varied across the year, by only accounting for 6% of Reco during winter and 16% during...

  20. The blastema and epimorphic regeneration in mammals.

    Science.gov (United States)

    Seifert, Ashley W; Muneoka, Ken

    2018-01-15

    Studying regeneration in animals where and when it occurs is inherently interesting and a challenging research topic within developmental biology. Historically, vertebrate regeneration has been investigated in animals that display enhanced regenerative abilities and we have learned much from studying organ regeneration in amphibians and fish. From an applied perspective, while regeneration biologists will undoubtedly continue to study poikilothermic animals (i.e., amphibians and fish), studies focused on homeotherms (i.e., mammals and birds) are also necessary to advance regeneration biology. Emerging mammalian models of epimorphic regeneration are poised to help link regenerative biology and regenerative medicine. The regenerating rodent digit tip, which parallels human fingertip regeneration, and the regeneration of large circular defects through the ear pinna in spiny mice and rabbits, provide tractable, experimental systems where complex tissue structures are regrown through blastema formation and morphogenesis. Using these models as examples, we detail similarities and differences between the mammalian blastema and its classical counterpart to arrive at a broad working definition of a vertebrate regeneration blastema. This comparison leads us to conclude that regenerative failure is not related to the availability of regeneration-competent progenitor cells, but is most likely a function of the cellular response to the microenvironment that forms following traumatic injury. Recent studies demonstrating that targeted modification of this microenvironment can restrict or enhance regenerative capabilities in mammals helps provide a roadmap for eventually pushing the limits of human regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A reference genome of the European beech (Fagus sylvatica L.).

    Science.gov (United States)

    Mishra, Bagdevi; Gupta, Deepak K; Pfenninger, Markus; Hickler, Thomas; Langer, Ewald; Nam, Bora; Paule, Juraj; Sharma, Rahul; Ulaszewski, Bartosz; Warmbier, Joanna; Burczyk, Jaroslaw; Thines, Marco

    2018-06-01

    The European beech is arguably the most important climax broad-leaved tree species in Central Europe, widely planted for its valuable wood. Here, we report the 542 Mb draft genome sequence of an up to 300-year-old individual (Bhaga) from an undisturbed stand in the Kellerwald-Edersee National Park in central Germany. Using a hybrid assembly approach, Illumina reads with short- and long-insert libraries, coupled with long Pacific Biosciences reads, we obtained an assembled genome size of 542 Mb, in line with flow cytometric genome size estimation. The largest scaffold was of 1.15 Mb, the N50 length was 145 kb, and the L50 count was 983. The assembly contained 0.12% of Ns. A Benchmarking with Universal Single-Copy Orthologs (BUSCO) analysis retrieved 94% complete BUSCO genes, well in the range of other high-quality draft genomes of trees. A total of 62,012 protein-coding genes were predicted, assisted by transcriptome sequencing. In addition, we are reporting an efficient method for extracting high-molecular-weight DNA from dormant buds, by which contamination by environmental bacteria and fungi was kept at a minimum. The assembled genome will be a valuable resource and reference for future population genomics studies on the evolution and past climate change adaptation of beech and will be helpful for identifying genes, e.g., involved in drought tolerance, in order to select and breed individuals to adapt forestry to climate change in Europe. A continuously updated genome browser and download page can be accessed from beechgenome.net, which will include future genome versions of the reference individual Bhaga, as new sequencing approaches develop.

  2. Joint Slovak-Ukraine-Germany Beech Ecosystems as the World Natural Heritage

    Directory of Open Access Journals (Sweden)

    Vološčuk Ivan

    2014-08-01

    Full Text Available The European beech Fagus sylvatica L. ssp. sylvatica L. is exclusively found in Europe. The beech survived the ice age in small refuges in the south and south-east Europe and went on to colonise large parts of the continent. The post-ice age colonisation of the landscape by the beech took place parallel to the settlement of land by humans and the formation of a more complex society. For centuries much of the Carpathian mountain forests remained untouched (Fig. 1. Virgin forests constitute a natural heritage of global significance. In 2007, 10 protected areas with the Primeval Beech Forests of Carpathians (Slovakia, Ukraine were added to UNESCO’s World Heritage List. On 25 June 2011, the UNESCO World Heritage Committee added five of Germany’s beech forest protected areas to the World Heritage List. This extended the transboundary world natural heritage site ‘Primeval Beech Forest of the Carpathians’, located in the Slovak Republic and Ukraine, to include a German forest protected areas, and renamed it ‘Primeval Beech Forests of the Carpathians and Ancient Beech Forests of Germany’. This paper is aimed at the presentation of the outstanding universal value of the ecological processes in the Joint World Heritage Sites, short description of protected areas and principles of their integrated management plan. This paper also deals with problems in management plan realisation in practice. Ultimate goal is to achieve that management and socio-economic sustainable development practices are in harmony with primary objectives of World Heritage Site protection, biodiversity conservation, ecosystem and landscape stability, rational use of natural resources, ecotourism development and with potential of the landscape in largest possible extend.

  3. Carbon and Nitrogen Pools and Fluxes in Adjacent Mature Norway Spruce and European Beech Forests

    Directory of Open Access Journals (Sweden)

    Filip Oulehle

    2016-11-01

    Full Text Available We compared two adjacent mature forest ecosystem types (spruce vs. beech to unravel the fate of assimilated carbon (C and the cycling of organic and inorganic nitrogen (N without the risk of the confounding influences of climatic and site differences when comparing different sites. The stock of C in biomass was higher (258 t·ha−1 in the older (150 years beech stand compared to the younger (80 years planted spruce stand (192 t·ha−1, whereas N biomass pools were comparable (1450 kg·ha−1. Significantly higher C and N soil pools were measured in the beech stand, both in forest floor and mineral soil. Cumulative annual CO2 soil efflux was similar among stands, i.e., 9.87 t·ha−1·year−1 of C in the spruce stand and 9.01 t·ha−1·year−1 in the beech stand. Soil temperature explained 78% (Q10 = 3.7 and 72% (Q10 = 4.2 of variability in CO2 soil efflux in the spruce and beech stand, respectively. However, the rather tight N cycle in the spruce stand prevented inorganic N losses, whereas losses were higher in the beech stand and were dominated by nitrate in the mineral soil. Our results highlighted the long-term consequences of forest management on C and N cycling.

  4. Some properties of LVL composed of poplar and beech veneer and possibilities of their application for window frames

    Directory of Open Access Journals (Sweden)

    Zdravković Vladislav

    2017-01-01

    Full Text Available The subject of this paper was a research of physical and mechanical properties of LVL composed of peeled poplar veneers in core layers and only outer layers of beech peeled veneers, so as the examination of window frame glue joint strength produced of this material. LVL boards have been hot pressed in industrial conditions, using appropriate phenol formaldehyde (PP adhesive. Samples for corner window frame glue joint strength testing were glued with PVAc D4 class adhesive. Statistical analysis showed that there were significant differences both in moisture content and density of LVL boards regarding their thickness, while in the case of hardness this difference did not exist. Examinations of LVL glue line shear strength showed that both phenol formaldehyde (PP and PVAc D4 class adhesives fulfilled standard requirements. The results of corner window frame double tenon glue joint strength produced from combined poplar-beech veneer LVL indicated that such material could be used to produce window frame corner joint, strong enough to withstand the additional load, without an increase of the cross section.

  5. Cardiomyocyte Regeneration

    Directory of Open Access Journals (Sweden)

    Toshio Nakanishi

    2013-01-01

    Full Text Available The heart was initially believed to be a terminally differentiated organ; once the cardiomyocytes died, no recovery could be made to replace the dead cells. However, around a decade ago, the concept of cardiac stem cells (CSCs in adult hearts was proposed. CSCs differentiate into cardiomyocytes, keeping the heart functioning. Studies have proved the existence of stem cells in the heart. These somatic stem cells have been studied for use in cardiac regeneration. Moreover, recently, induced pluripotent stem cells (iPSCs were invented, and methodologies have now been developed to induce stable cardiomyocyte differentiation and purification of mature cardiomyocytes. A reprogramming method has also been applied to direct reprogramming using cardiac fibroblasts into cardiomyocytes. Here, we address cardiomyocyte differentiation of CSCs and iPSCs. Furthermore, we describe the potential of CSCs in regenerative biology and regenerative medicine.

  6. Heart regeneration.

    Science.gov (United States)

    Breckwoldt, Kaja; Weinberger, Florian; Eschenhagen, Thomas

    2016-07-01

    Regenerating an injured heart holds great promise for millions of patients suffering from heart diseases. Since the human heart has very limited regenerative capacity, this is a challenging task. Numerous strategies aiming to improve heart function have been developed. In this review we focus on approaches intending to replace damaged heart muscle by new cardiomyocytes. Different strategies for the production of cardiomyocytes from human embryonic stem cells or human induced pluripotent stem cells, by direct reprogramming and induction of cardiomyocyte proliferation are discussed regarding their therapeutic potential and respective advantages and disadvantages. Furthermore, different methods for the transplantation of pluripotent stem cell-derived cardiomyocytes are described and their clinical perspectives are discussed. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Bionanomaterials for skin regeneration

    CERN Document Server

    Leonida, Mihaela D

    2016-01-01

    This book gives a concise overview of bionanomaterials with applications for skin regeneration. The advantages and challenges of nanoscale materials are covered in detail, giving a basic view of the skin structure and conditions that require transdermal or topical applications. Medical applications, such as wound healing, care for burns, skin disease, and cosmetic care, such as aging of the skin and photodamage, and how they benefit from bionanomaterials, are described in detail. A final chapter is devoted to the ethical and social issues related to the use of bionanomaterials for skin regeneration. This is an ideal book for researchers in materials science, medical scientists specialized in dermatology, and cosmetic chemists working in formulations. It can also serve as a reference for nanotechnologists, dermatologists, microbiologists, engineers, and polymer chemists, as well as students studying in these fields.

  8. Biomaterials for cardiac regeneration

    CERN Document Server

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  9. Comparison of ozone uptake and sensitivity between a phytotron study with young beech and a field experiment with adult beech (Fagus sylvatica)

    International Nuclear Information System (INIS)

    Nunn, Angela J.; Kozovits, A.R.; Reiter, I.M.; Heerdt, C.; Leuchner, M.; Luetz, C.; Liu, X.; Low, M.; Winkler, J.B.; Grams, T.E.E.; Haeberle, K.-H.; Werner, H.; Fabian, P.; Rennenberg, H.; Matyssek, R.

    2005-01-01

    Chamber experiments on juvenile trees have resulted in severe injury and accelerated loss of leaves along with reduced biomass production under chronically enhanced O 3 levels. In contrast, the few studies conducted on adult forest trees in the field have reported low O 3 sensitivity. In the present study, young beech in phytotrons was more sensitive to O 3 than adult beech in the field, although employed O 3 regimes were similar. The hypotheses tested were that: (1) differences in O 3 uptake were caused by the ontogenetically higher stomatal conductance of young compared to adult trees (2) the experimental settings in the phytotrons enhanced O 3 uptake compared to field conditions, and (3) a low detoxification capacity contributes to the higher O 3 sensitivity of the young trees. The higher O 3 sensitivity of juvenile beech in the phytotrons is demonstrated to relate to both the experimental conditions and the physiological responsiveness inherent to tree age. - Juvenile beech trees in phytotrons are more sensitive to ozone than adult forest trees due to lower defence capacity and growth conditions

  10. Soil base saturation combines with Beech Bark Disease to influence composition and structure of Sugar Maple-Beech forests in an acid rain-impacted region

    Science.gov (United States)

    Lawrence, Gregory B.; McDonnell, Todd C.; Sullivan, Timothy J.; Dovciak, Martin; Bailey, Scott W.; Antidormi, Michael; Zarfos, Michael R.

    2018-01-01

    Sugar maple, an abundant and highly valued tree species in eastern North America, has experienced decline from soil calcium (Ca) depletion by acidic deposition, while beech, which often coexists with sugar maple, has been afflicted with beech bark disease (BBD) over the same period. To investigate how variations in soil base saturation combine with effects of BBD in influencing stand composition and structure, measurements of soils, canopy, subcanopy, and seedlings were taken in 21 watersheds in the Adirondack region of NY (USA), where sugar maple and beech were the predominant canopy species and base saturation of the upper B horizon ranged from 4.4 to 67%. The base saturation value corresponding to the threshold for Al mobilization (16.8%) helped to define the species composition of canopy trees and seedlings. Canopy vigor and diameter at breast height (DBH) were positively correlated (P soils, soil-Ca depletion and BBD may have created opportunities for gap-exploiting species such as red maple and black cherry, whereas in high-base saturation soils, sugar maple dominated the canopy. Where soils were beginning to recover from acidic deposition effects, sugar maple DBH and basal area increased progressively from 2000 to 2015, whereas for beech, average DBH did not change and basal area did not increase after 2010.

  11. The influence of fire retardants on the properties of beech and poplar veneers and plywood

    Directory of Open Access Journals (Sweden)

    Miljković Jovan

    2005-01-01

    Full Text Available Rising demands for fire resistance properties of wood construction and elements matching new standards have been an important part of building codes during the last decade. On the other side, lack of more detailed research on interaction between wood species and selected fire retardant chemicals even with basically one is evident. This is particularly truth with domestic wood species. In this research, beech and poplar veneers were immersed in 25% solutions of monoammonium phosphate (MP and sodium acetate (SA and impregnated for different periods of time. To determine the preliminary level of fire retardancy achieved in veneers before manufacturing of finished plywood, thermo gravimetric (TG and derivative thermo gravimetric (DTG methods were used. TG and DTG analyses of treated and untreated wood, as well as of fire retardants alone, were performed. The next properties of impregnated and no impregnated veneers and plywood were determined: absorption of imp regnant solution (A, weight percent gain (WPG of imp regnant, equilibrium moisture content (EMC, pH values, and in the case of plywood, strength and fire resistance. Fire resistance of plywood was tested in accordance with standard test for resistance to the effects of fire and the most efficient fire retardant, monoammonium phosphate, had the same result as TG/DTG analyses, which pointed out the validity of TG methods in predicting fire resistance of future products.

  12. Chemical Elements in Mulch and Litterfall of Beech Ecosystems and Their Total Turnover

    Directory of Open Access Journals (Sweden)

    Mariyana I. Lyubenovа

    2011-07-01

    Full Text Available The beech communities on the territory of Bulgaria had been objects of regional, local as well as large scale national investigations aiming their classification, determination of their ecological characteristics, conservation status, habitats etc. They are included as objects of the intensive monitoring of forest ecosystems in Bulgaria also. The investigations of chemical content of the litter – fall in these forests were conducted until now. The novelty of the present research is investigation of these elements in the mulch and the ratio between the established quantities calculation. The main goal is the biological turnover special features characterization of the investigated elements which give us a chance to define the investigated ecosystems state and functioning. The indexes as litter – mulch and acropetal coefficients were used for this aim. The content of macroelements as N, Ca and K and microelements as Pb, Zn, Mn and Fe in soils, mulch and in different litter fall fractions have been calculated. The investigation was carried out on three sample plots. During the investigation was established that the soils are characterized with acid reaction, high content of Fe, N and Mn and low content of Ca and K. The concentration of Zn and Pb are high also. The calculated average store of investigated elements in litter – fall is 81.312 kg.ha1 and in the mulch 314 kg.ha1. According to the acropetal coefficient N is accumulated mainly in the acorns, K – in the annual phytomass fractions and Ca – in the perennial fractions. The leaves and the acorns fraction accumulate Mn, and cupolas Fe. The litter – mulch coefficient vary from 1,6 (Mn to 4,2 (Pb. The tendencies of Zn and Ca turnovers acceleration are discovered, while the turnover of more investigated elements is inhibited. The litter – mulch coefficient for Zn and Ca is 0,8 and 1,4 accordingly, i.е. corresponding to the intensive type of turnovers which is not typical for the

  13. Estimation of beech pyrolysis kinetic parameters by Shuffled Complex Evolution.

    Science.gov (United States)

    Ding, Yanming; Wang, Changjian; Chaos, Marcos; Chen, Ruiyu; Lu, Shouxiang

    2016-01-01

    The pyrolysis kinetics of a typical biomass energy feedstock, beech, was investigated based on thermogravimetric analysis over a wide heating rate range from 5K/min to 80K/min. A three-component (corresponding to hemicellulose, cellulose and lignin) parallel decomposition reaction scheme was applied to describe the experimental data. The resulting kinetic reaction model was coupled to an evolutionary optimization algorithm (Shuffled Complex Evolution, SCE) to obtain model parameters. To the authors' knowledge, this is the first study in which SCE has been used in the context of thermogravimetry. The kinetic parameters were simultaneously optimized against data for 10, 20 and 60K/min heating rates, providing excellent fits to experimental data. Furthermore, it was shown that the optimized parameters were applicable to heating rates (5 and 80K/min) beyond those used to generate them. Finally, the predicted results based on optimized parameters were contrasted with those based on the literature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Regeneration of Optic Nerve

    Directory of Open Access Journals (Sweden)

    Kwok-Fai So

    2011-05-01

    Full Text Available The optic nerve is part of the central nervous system (CNS and has a structure similar to other CNS tracts. The axons that form the optic nerve originate in the ganglion cell layer of the retina and extend through the optic tract. As a tissue, the optic nerve has the same organization as the white matter of the brain in regard to its glia. There are three types of glial cells: Oligodendrocytes, astrocytes, and microglia. Little structural and functional regeneration of the CNS takes place spontaneously following injury in adult mammals. In contrast, the ability of the mammalian peripheral nervous system (PNS to regenerate axons after injury is well documented. A number of factors are involved in the lack of CNS regeneration, including: (i the response of neuronal cell bodies against the damage; (ii myelin-mediated inhibition by oligodendrocytes; (iii glial scarring, by astrocytes; (iv macrophage infiltration; and (v insufficient trophic factor support. The fundamental difference in the regenerative capacity between CNS and PNS neuronal cell bodies has been the subject of intensive research. In the CNS the target normally conveys a retrograde trophic signal to the cell body. CNS neurons die because of trophic deprivation. Damage to the optic nerve disconnects the neuronal cell body from its target-derived trophic peptides, leading to the death of retinal ganglion cells. Furthermore, the axontomized neurons become less responsive to the peptide trophic signals they do receive. On the other hand, adult PNS neurons are intrinsically responsive to neurotrophic factors and do not lose trophic responsiveness after axotomy. In this talk different strategies to promote optic-nerve regeneration in adult mammals are reviewed. Much work is still needed to resolve many issues. This is a very important area of neuroregeneration and neuroprotection, as currently there is no cure after traumatic optic nerve injury or retinal disease such as glaucoma, which

  15. Cell migration during heart regeneration in zebrafish.

    Science.gov (United States)

    Tahara, Naoyuki; Brush, Michael; Kawakami, Yasuhiko

    2016-07-01

    Zebrafish possess the remarkable ability to regenerate injured hearts as adults, which contrasts the very limited ability in mammals. Although very limited, mammalian hearts do in fact have measurable levels of cardiomyocyte regeneration. Therefore, elucidating mechanisms of zebrafish heart regeneration would provide information of naturally occurring regeneration to potentially apply to mammalian studies, in addition to addressing this biologically interesting phenomenon in itself. Studies over the past 13 years have identified processes and mechanisms of heart regeneration in zebrafish. After heart injury, pre-existing cardiomyocytes dedifferentiate, enter the cell cycle, and repair the injured myocardium. This process requires interaction with epicardial cells, endocardial cells, and vascular endothelial cells. Epicardial cells envelope the heart, while endocardial cells make up the inner lining of the heart. They provide paracrine signals to cardiomyocytes to regenerate the injured myocardium, which is vascularized during heart regeneration. In addition, accumulating results suggest that local migration of these major cardiac cell types have roles in heart regeneration. In this review, we summarize the characteristics of various heart injury methods used in the research community and regeneration of the major cardiac cell types. Then, we discuss local migration of these cardiac cell types and immune cells during heart regeneration. Developmental Dynamics 245:774-787, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. Sustainable Regeneration of Nanoparticle Enhanced Activated Carbon in Water

    Science.gov (United States)

    The regeneration and reuse of exhausted granular activated carbon (GAC) is an appropriate method for lowering operational and environmental costs. Advanced oxidation is a promising environmental friendly technique for GAC regeneration. The main objective of this research was to ...

  17. Beech Range Extension and Vegetation History: Pollen Stratigraphy of Two Wisconsin Lakes.

    Science.gov (United States)

    Webb, Sara L

    1987-12-01

    The pollen stratigraphy of two small lakes in eastern Wisconsin (Radtke Lake, Washington county, and Gass Lake, Manitowoc County) records the Holocene (past 10 000 yr) spread of beech (Fagus grandifolia: Fagaceae). Radiocarbon dates were obtained for the oldest stratigraphic levels at which beech pollen appeared consistently in amounts > 0.5% of terrestrial pollen. A spatially continuous pattern of beech expansion from the north was ruled out, because beech trees grew in Wisconsin by 6000 BP, 2000 yr before adjacent populations were established to the north. Alternative geographic patterns of speed (from the south or east) were spatially discontinuous, requiring seed dispersal distances of perhaps 25-130 km. That beechnuts could be dispersed across such distances suggests (1) the involvement of Blue Jays, Passenger Pigeons, or other vertebrates, and (2) a capacity for reaching climatically controlled range limits, given sufficient time despite such discontinuities in habitat. A lag 1000-2000 yr between the establishment of source populations in Michigan and Indiana and the appearance of beech in Wisconsin suggests that low-probability dispersal events were involved and that dispersal constraints limited the range of beech during this time, although climatic and edaphic explanations for the lag cannot be ruled out. Pollen data from the two sites reveal other features of vegetation history in eastern Wisconsin: an open Picea-Fraxinus woodland prior to 11 000 BP; sequence of Picea, Abies, Betula, and then Pinus forests between 11 000 and 7500 BP; the establishment of a coniferous/deciduous forest ecotone ("tension zone") ° 7000 BP in this region; and the presence of Quercus-dominanted deciduous forests from 7000 BP until 110 BP (time of Euro-American settlement), a period punctuated by a gradual decrease in Ulmus populations (° 4500 and 5700 BP at the two sites) and by an increase in mesophytic tree abundance at the expense of Quercus after 3500 BP. © 1987 by the

  18. Biological regeneration of para-nitrophenol loaded activated carbon

    International Nuclear Information System (INIS)

    Durrani, M.A.Q.; Martin, R.J.

    1997-01-01

    Biological regeneration is one of several methods that may be used to restore the adsorptive capacity of exhausted granular activated carbon (GAC). This study deals with in-situ biological regeneration on a pilot scale. The principal objective of this research was to ascertain whether biological regeneration of GAC could occur under conditions typical of water treatment. The important parameters which may have the greatest impact on bio regeneration of a given adsorbate were studied. The research investigated the extent of bio regeneration for para-nitrophenol (PNP) of concentration 50 mg/L. Bio regeneration in the total exhaustion system was evaluated in terms of regeneration efficiency and the substrate removal. A three mode procedure was followed for each bio regeneration run. The prepared carbon was initially exhausted with an adsorbate; it was then bio regenerated for para-nitrophenol (PNP) of concentration 50 mg/L. Bio regeneration in he total exhaustion system was evaluated in terms of regeneration efficiency and the substrate removal. A three mode procedure was followed for each bio regeneration run. The prepared carbon was initially exhausted with an adsorbate; it was then bio regenerated with a mixed culture of bacteria, and lastly the carbon was re-saturated. In the totally exhausted GAC system, the bio regeneration was enhanced by increasing the during of regeneration for a fixed initial biomass content of the bioreactor. The bio regeneration efficiency of the totally exhausted (with PNP) GAC the empty bed contact time (EBCT) and the initial concentration of the substrate had a profound effect on the bio regeneration efficiency. Bacterial counts in the effluents of regenerated GAC columns were significantly more than those of fresh carbon effluents. (author)

  19. Assessment of a relaxed eddy accumulation for measurements of fluxes of biogenic volatile organic compounds: Study over arable crops and a mature beech forest

    DEFF Research Database (Denmark)

    Gallagher, M.W.; Clayborough, R.; Beswick, K.M.

    2000-01-01

    A relaxed eddy accumulation (REA) system, based on the design by Beverland et al. (Journal of Geophysics Research 101 (D17) 22, 807-22, 815), for the measurement of biogenic VOC species was evaluated by intercomparison with an eddy correlation CO2 flux system over a mature deciduous beech canopy...... (Fagus Sylvatica) during the FOREXNOX program. Measurements from a site where winter wheat and barley (Hordeum Vulgare ann Triticum Aestivum) were being harvested are also presented. The system was inter-compared with two different eddy correlation systems for measuring CO2 fluxes. Good results were...

  20. Ectomycorrhizal Communities on the Roots of Two Beech (Fagus sylvatica) Populations from Contrasting Climates Differ in Nitrogen Acquisition in a Common Environment.

    Science.gov (United States)

    Leberecht, Martin; Dannenmann, Michael; Gschwendtner, Silvia; Bilela, Silvija; Meier, Rudolf; Simon, Judy; Rennenberg, Heinz; Schloter, Michael; Polle, Andrea

    2015-09-01

    Beech (Fagus sylvatica), a dominant forest species in Central Europe, competes for nitrogen with soil microbes and suffers from N limitation under dry conditions. We hypothesized that ectomycorrhizal communities and the free-living rhizosphere microbes from beech trees from sites with two contrasting climatic conditions exhibit differences in N acquisition that contribute to differences in host N uptake and are related to differences in host belowground carbon allocation. To test these hypotheses, young trees from the natural regeneration of two genetically similar populations, one from dryer conditions (located in an area with a southwest exposure [SW trees]) and the other from a cooler, moist climate (located in an area with a northeast exposure [NE trees]), were transplanted into a homogeneous substrate in the same environment and labeled with (13)CO2 and (15)NH4 (+). Free-living rhizosphere microbes were characterized by marker genes for the N cycle, but no differences between the rhizospheres of SW or NE trees were found. Lower (15)N enrichment was found in the ectomycorrhizal communities of the NE tree communities than the SW tree communities, whereas no significant differences in (15)N enrichment were observed for nonmycorrhizal root tips of SW and NE trees. Neither the ectomycorrhizal communities nor the nonmycorrhizal root tips originating from NE and SW trees showed differences in (13)C signatures. Because the level of (15)N accumulation in fine roots and the amount transferred to leaves were lower in NE trees than SW trees, our data support the suggestion that the ectomycorrhizal community influences N transfer to its host and demonstrate that the fungal community from the dry condition was more efficient in N acquisition when environmental constraints were relieved. These findings highlight the importance of adapted ectomycorrhizal communities for forest nutrition in a changing climate. Copyright © 2015, American Society for Microbiology. All Rights

  1. Climate threats on growth of rear-edge European beech peripheral populations in Spain

    NARCIS (Netherlands)

    Dorado-Liñán, I.; Akhmetzyanov, L.; Menzel, A.

    2017-01-01

    European beech (Fagus sylvatica L.) forests in the Iberian Peninsula are a clear example of a temperate forest tree species at the rear edge of its large distribution area in Europe. The expected drier and warmer climate may alter tree growth and species distribution. Consequently, the peripheral

  2. Differential impacts of calcium and aluminum treatments on sugar maple and American beech growth dynamics

    Science.gov (United States)

    Joshua M. Halman; Paul G. Schaberg; Gary J. Hawley; Christopher F. Hansen; Timothy J. Fahey

    2015-01-01

    Acid deposition induced losses of calcium (Ca) from northeastern forests have had negative effects on forest health for decades, including the mobilization of potentially phytotoxic aluminum (Al) from soils. To evaluate the impact of changes in Ca and Al availability on sugar maple (Acer saccharum Marsh.) and American beech (Fagus...

  3. Methanol and other VOC fluxes from a Danish beech forest during late springtime

    DEFF Research Database (Denmark)

    Schade, Gunnar W.; Solomon, Sheena J.; Dellwik, Ebba

    2011-01-01

    In-canopy mixing ratio gradients and above-canopy fluxes of several volatile organic compounds (VOCs) were measured using a commercial proton transfer reaction mass spectrometer (PTR-MS) in a European beech (Fagus sylvatica) forest in Denmark. Fluxes of methanol were bidirectional: Emission...

  4. Mapping beech (Fagus sylvatica L.) forest structure with airborne hyperspectral imagery

    CSIR Research Space (South Africa)

    Cho, Moses A

    2009-06-01

    Full Text Available The objective of this study was to assess the utility of hyperspectral data in estimating and mapping forest structural parameters including mean diameter-at-breast-height (DBH), mean tree height and tree density of a closed canopy beech forest...

  5. SOIL CO2 EFFLUX FROM ISOTOPICALLY LABELED BEECH AND SPRUCE IN SOUTHERN GERMANY

    Science.gov (United States)

    • Carbon acquisition and transport to roots in forest trees is difficult to quantify and is affected by a number of factors, including micrometeorology and anthropogenic stresses. The canopies of mature European beech (Fagus sylvatica) and Norway spruce (Picea abies) were expose...

  6. ESTIMATING ROOT RESPIRATION IN SPRUCE AND BEECH: DECREASES IN SOIL RESPIRATION FOLLOWING GIRDLING

    Science.gov (United States)

    A study was undertaken to follow seasonal fluxes of CO2 from soil and to estimate the contribution of autotrophic (root + mycorrhizal) to total soil respiration (SR) in a mixed stand of European beech (Fagus sylvatica) and Norway spruce (Picea abies) near Freising, Germany. Matu...

  7. Fertilization increases diameter growth of birch-beech-maple trees in New Hampshire

    Science.gov (United States)

    L. O. Safford

    1973-01-01

    In a 60-year-old northern hardwood stand treated with lime plus NPK fertilizer, the following increases in average basal area growth rate over untreated trees were observed: sugar maple 128 percent, paper birch 69 percent, yellow birch 51 percent, and beech 20 percent. Magnitude of response was inversely related to relative growth rate of the species. Growth rate...

  8. Nitrous oxide emissions from a beech forest floor measured by eddy covariance and soil enclosure techniques

    DEFF Research Database (Denmark)

    Pihlatie, M.; Rinne, J.; Ambus, P.

    2005-01-01

    Spring time nitrous oxide (N2O) emissions from an old beech (Fagus sylvatica L.) forest were measured with eddy covariance (EC) and chamber techniques. The aim was to obtain information on the spatial and temporal variability in N2O emissions and link the emissions to soil environmental parameters...

  9. Diversity of dead wood inhabiting fungal and bryophytes in semi-natural beech forests in Europe

    NARCIS (Netherlands)

    Ódor, P.; Heilmann-Clausen, J.; Christensen, M.; Aude, E.; Dort, van K.W.; Piltaver, A.; Siller, I.; Veerkamp, M.T.; Walleyn, R.; Standovár, T.; Hees, van A.F.M.; Kosec, J.; Matocec, N.; Kraigher, H.; Grebenc, T.

    2006-01-01

    Saproxylic organisms are among the most threatened species in Europe and constitute a major conservation problem because they depend on the most important forestry product - dead wood. Diversity of fungal and bryophyte communities occurring on dead beech trees was analyzed in five European countries

  10. A contribution to the sessile oak site and beech site defining in central Serbia

    Directory of Open Access Journals (Sweden)

    Krstić Milun

    2009-01-01

    Full Text Available The study was carried out in sessile oak forests and beech forests in the region central Serbia. The stands are classified as pure stands with the percentage of other species up to 10% per tree number, mixed forests of sessile oak with other species, and mixed forests of beech with other species, whose percentage does not exceed 50%. Altogether 257 stands were monitored - 202 beech stands and 55 sessile oak stands. By the applied method of defining the local heat potential (Lujić, 1960, modified by Ratknić et al. (2001 and Krstić (2004, 2008, which represents possibility of soil heating without vegetation, were determined. In this way, a scale of 162 possible combinations of local heat potential was obtained, which explains more precisely the dependence of beech stands and sessile oak stands on the topographic conditions. By applying the weighted values of the thermal co-ordinates of aspect and slope (E for each altitudinal belt of 100 m, it was concluded that pure stands have the widest ecological range. Pure beech stands occur at the sites with 34 combinations of thermal co-ordinates E.V=4.6 to 8.12. Pure sessile oak stands occur at the sites with 12 combinations of thermal co-ordinates E.V=5.10 to 8.11. The percentage of mixed beech stands with other broadleaf species is the highest at the sites with the co-ordinate V=10-11 (at the altitudes between 700 and 900 m is about 60 %. Mixed stands of sessile oak and beech are located on the terrains with combinations of thermal co-ordinates E.V=7.9 to 8.12. By using the local heat potential of a region, it can be identified which sites, i.e. which combinations of exposure, slope and altitude belong to the particular tree species. Consequently, a more reliable selection of tree species can be done for the bio-reclamation of barrens and other deforested terrains.

  11. Comparison of the chemical properties of wheat straw and beech fibers following alkaline wet oxidation and laccase treatments

    DEFF Research Database (Denmark)

    Schmidt, A. S.; Mallon, S.; Thomsen, Anne Belinda

    2002-01-01

    Wheat straw (Triticum aestivum) and beech (Fagus sylvatica), were used to evaluate the effects of two pre-treatment processes (alkaline wet oxidation and enzyme treatment with laccase) on lignocellulosic materials for applications in particleboards and fiberboards. Wheat straw and beech fibers...... treatment gave a more reactive surface than alkaline wet oxidation for wheat straw, whereas the opposite was observed for beech. Fourier transform infrared (FT-IR) spectroscopy showed an almost complete loss of the ester carbonyl stretching signal and the corresponding C-C-O stretching in wet...

  12. Future of Beech in Southeast Europe from the Perspective of Evolutionary Ecology

    Directory of Open Access Journals (Sweden)

    MÁTYÁS, Csaba

    2010-01-01

    Full Text Available The aim of this study is to provide quantitative information on the effect of climaticchange on the growth and vitality of European beech: although the species is considered in itsoptimum highly plastic and adaptable, it becomes climate-sensitive closer to its xeric (lowerdistribution limits. The future of beech in Southeast Europe requires special attention because thisregion harbours significant populations living at or near their xeric distribution boundary. Even thoughthe low elevation occurrences are uniquely vulnerable to climatic shifts, observations and modellingstudies pertaining to this region are particularly scarce.Out of climatic factors determining the xeric distributional limits for beech, Ellenberg’s droughtindex (EQ appeared as the most influential. Growth response analyses in comparative tests haveconfirmed the existence of macroclimatic adaptation of beech and have proven that warming and morearid conditions lead to decline of growth and vitality, while no decline was observed if EQ changed inthe opposite direction. The response to weather extremes was investigated in field plots. Recurrentsummer droughts of 3 to 4 consecutive years, above mean EQ value 40-42 resulted in pest and diseaseattacks and mass mortality.The discussed approaches indicate consistently a high level of uncertainty regarding the future ofbeech at the xeric limit in Southeast Europe. According to field observations and bioclimatic data inHungary, a large part of low-elevation beech forests presently in the zone of EQ index 20 might bethreatened by the warming in the second half of the century, while higher-elevation occurrences mayremain stable.The interpretation of the results bears some stipulations, such as the consequence of ecologicaland human interactions in influencing present distribution patterns, the unclear role of persistence,natural selection and plasticity and uncertainties of climate projections. Grim projections mayprobably be partly

  13. Thirty-two years of change in an old-growth Ohio beech-maple forest.

    Science.gov (United States)

    Runkle, James R

    2013-05-01

    Old-growth forests dominated by understory-tolerant tree species are among forest types most likely to be in equilibrium. However, documentation of the degree to which they are in equilibrium over decades-long time periods is lacking. Changes in climate, pathogens, and land use all are likely to impact stand characteristics and species composition, even in these forests. Here, 32 years of vegetation changes in an old-growth beech (Fagus grandifolia)-sugar maple (Acer saccharum) forest in Hueston Woods, southwest Ohio, USA, are summarized. These changes involve canopy composition and structure, turnover in snags, and development of vegetation in treefall gaps. Stand basal area and canopy density have changed little in 32 years. However, beech has decreased in canopy importance (49% to 32%) while sugar maple has increased (32% to 47%). Annual mortality was about 1.3% throughout the study period. Mortality rates increased with stem size, but the fraction of larger stems increased due to ingrowth from smaller size classes. Beech was represented by more very large stems than small canopy stems: over time, death of those larger stems with inadequate replacement has caused the decrease in beech importance. Sugar maple was represented by more small canopy stems whose growth has increased its importance. The changes in beech and sugar maple relative importance are hypothesized to be due to forest fragmentation mostly from the early 1800s with some possible additional effects associated with the formation of the state park. Snag densities (12-16 snags/ha) and formation rates (1-3 snags.ha(-1).yr(-1)) remained consistent. The treefall gaps previously studied are closing, with a few, large stems remaining. Death of gap border trees occurs consistently enough to favor species able to combine growth in gaps and survival in the understory.

  14. The impact of small terrestrial mammals on beech (Fagus sylvatica plantations in spruce monoculture

    Directory of Open Access Journals (Sweden)

    Luboš Purchart

    2007-01-01

    Full Text Available Little is known about the impact of small terrestrial mammals on forest regeneration as yet. In order to determine the level of small rodent impact on artificial forest regeneration, 508 saplings have been researched in a spruce monoculture in the Drahany Uplands. With the objective to hone the interpretation of the data, small terrestrial rodents were trapped to help determine species spectrum. The occurrence of Apodemus flavicollis, Clethrionomys glareolus and Sorex araneus was verified. In 52 cases damage to the trunk caused by small rodents was monitored (10.1% of all saplings. 8 specimens (1.6% had their branches nibbled and 9 saplings (1.8% had tips of branches or trunk tops browsed. Browsing by Lepus europaeus – 423 (83.3% of all damaged specimens was significant.

  15. Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians

    Directory of Open Access Journals (Sweden)

    Mihaela Paucã-Comãnescu

    2009-11-01

    Full Text Available The hill beech forests cover most of the woody area in the Doftana Valley. The present study refers, for the first time, to two beech forests typical to this belt, which belong to the phytocoenological associations Epipactieto-Fagetum (Resmeritã,1972, in the Lunca Mare area, and Hieracio rotundati-Fagetum (Vida 1983, Täuber 1987 in the Sotrile area, from floristic, structural, biomass and necromassaccumulation point of view, within the framework of the vertical structure of biocoenosis.The limestone substratum, occasionally with small outcrops in the first beech forest, differs chiefly through the pH levels (6.34-5.67 from the siliceous substratum (pH 5.11-4.36 in the second beech forest. The layer of trees is dominated by Fagus sylvatica in both forests; this species is associated with Cerasus avium (4.5%,Acer pseudoplatanus (2% and Sorbus torminalis (2% in the first beech forest, and is monodominant in the second. Although the forest underwent selective cuts, more intense in the Lunca Mare area, the aboveground ligneous biomass reaches nowadays 222 t/ha in the Lunca Mare area compared to only 163 t/ha in the Sotrile area; theaverage height is 28.8±2.49 m and 23.7±1.12 m, respectively, and the diameter is 33.30±7.9 cm and 31.60±6.28 cm, respectively. The species of macrofungi, not very numerous during the study because of scarce precipitations (6 and 7 species, respectively,are predominant on the rhytidoma trees in the beech forest rooted on the limestone ground; in the Sotrile beech forest they are joined by mycorrhizal and parasite species. The layer of shrub is underdeveloped. The herbaceous layer is discontinuous, and includes, along herbs, small plants and saplings belonging to the ligneous species and to liana Hedera helix. The maximal value of the aboveground biomass of thelayer is 317 kg/ha DM in the Lunca Mare area and 235 kg /ha DM in the Sotrile area.Bryophyta is present in large quantities, especially in the ªotrile area

  16. Brownfield regeneration: Towards strengthening social cohesion?

    Directory of Open Access Journals (Sweden)

    Minić Marta

    2016-01-01

    Full Text Available In broader terms, the paper refers to the topic of brownfield regeneration, as one of the most complex mechanisms for sustainable spatial development. In addition to the fact that brownfield regeneration demands a variety of instruments, such as: tax subsidies, the change of land use ownership, soil remediation, planning regulative amendments, etc., the complexity of brownfield regeneration is primarily seen in a number of stakeholders participating in such a process. Thus, the paper focuses on the social aspect of brownfield regeneration - precisely, on researching the community role and reviewing the possibilities for achieving the 'local' interests in complex developmental processes. The main research hypothesis is that brownfield regeneration positively affects the creation of and strengthening the social cohesion in the areas close to the brownfield site. More precisley, the paper presents the ways towards strenghtening social cohesion in the initial phase of the brownfield regeneration process, as well as the effects of such a process in its operationalisation phase on social cohesion. The thesis is examined by two main parameters: 1 participation of local community, and 2 social costs and benefits of brownfield regeneration versus greenfield investment. The research results are presented in the form of argumentative essay. In fact, the critical overview of arguments for and against the main research hypothesis is provided based on the review of interdisciplinary literature in the domain of brownfield regeneration. Such research organisation ensures the identification and description of the measures needed for strengthening social cohesion, as an utmost goal of this research. The final research contribution is about offering the guidelines for similar methodological approach in urban research.

  17. Effect on a long-term afforestation of pine in a beech domain in NE-Spain as reflected in soil C and N isotopic signature

    Science.gov (United States)

    Girona García, Antonio; Badía-Villas, David; González-Pérez, José Antonio; Tomás Jiménez-Morillo, Nicasio; Martí-Dalmau, Clara

    2015-04-01

    enriched in 13C as compared to that from beech (OL enrichment factor= 1.24 ± 0.13 per thousand). Along the soil profile the C isotopic signature (d13C) reflects the main vegetation signature being higher in pine than beech in the organic soil horizons (OL, OF and OH) down to the first mineral Ah horizon. At deeper horizons d13C value tends to equal that of the original beech soil indicating a limited influence of the afforested specie with depth even 100 years after afforestation. A consistent enrichment in d15N with depth was observed in the two profiles. This N enrichments have been related with progressive N losses being particularly pronounced in forest soils (Szpak, 2014 and refs therein). This phenomenon can be also related to migrations of N forms in a more evolved organic matter. In this view N losses in organic layers under beech seem to be less pronounced that under the alien pine. REFERENCES: Andreeva BD, Zech M, Glaser B, Erbajeva MA, Chimitdorgieva, Ermakova OD, Zech, W. (2013). Stable isotope (δ13C, δ15N, δ18O) record of soils in Buryatia, southern Siberia: Implications for biogeochemical and paleoclimatic interpretations. Quaternary International 290-291 (2013) 82-94 pp. Carceller F, Vallejo VR (1996). Influencia de la vegetación en los procesos de podsolización en los suelos de la Sierra del Moncayo (Zaragoza). Geogaceta 1127-1130. Szpak P (2014). Complexities of nitrogen isotope biogeochemistry in plant-soil systems: implications for the study of ancient agricultural and animal management practices. Front. Plant Sci. 5: 288 1-19 pp. Acknowledgements: This study is part of the results of the FUEGOSOL (CGL2013-43440-R) and GEOFIRE Projects (CGL2012-38655-C04-01) funded by the Spanish Ministry for Economy and Competitiveness. N.T Jiménez-Morillo is funded by a FPI research grant (BES-2013-062573).

  18. Desulfurization sorbent regeneration

    Science.gov (United States)

    Jalan, V.M.; Frost, D.G.

    1982-07-07

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

  19. The Results of Complex Selective Logging in Beech-Hornbeam Tree Stands of the Greater Caucasus in Azerbaijan

    Directory of Open Access Journals (Sweden)

    A. B. Yakhyaev

    2014-06-01

    Full Text Available The results of complex selective logging conducted in beech-hornbeam tree stands on the northeastern slope of the Greater Caucasus are analyzed in the paper. Experiments were carried out in two forestry districts, involving beech stands, comprising 2–3 units, with 30° slopes, in beech forests with woodruff, fescue and forb forest types. It has been revealed that for recovering the main tree species, as well as for increasing productivity and sustainability of the beech-hornbeam tree stands, which was spread out in the northern exposures, 2–3 repetitions of complex selective logging are recommended. It is recommended that in order to increase the amount of beech in the tree stand composition to 6–8 units in young stands and to 4–6 units at the slopes of south exposures, to complete 3–4 thinning operations, with the increasing beech share to 4–5 units in the upper story and in the undergrowth.

  20. Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

    Directory of Open Access Journals (Sweden)

    Min Jung Kwon

    2016-01-01

    Full Text Available Axons in central nervous system (CNS do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif ligand 2 (CCL2 seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs. Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.

  1. Mammalian Cochlear Hair Cell Regeneration and Ribbon Synapse Reformation

    Directory of Open Access Journals (Sweden)

    Xiaoling Lu

    2016-01-01

    Full Text Available Hair cells (HCs are the sensory preceptor cells in the inner ear, which play an important role in hearing and balance. The HCs of organ of Corti are susceptible to noise, ototoxic drugs, and infections, thus resulting in permanent hearing loss. Recent approaches of HCs regeneration provide new directions for finding the treatment of sensor neural deafness. To have normal hearing function, the regenerated HCs must be reinnervated by nerve fibers and reform ribbon synapse with the dendrite of spiral ganglion neuron through nerve regeneration. In this review, we discuss the research progress in HC regeneration, the synaptic plasticity, and the reinnervation of new regenerated HCs in mammalian inner ear.

  2. Testing the applicability of BIOME-BGC to simulate beech gross primary production in Europe using a new continental weather dataset

    OpenAIRE

    Chiesi , Marta; Chirici , Gherardo; Marchetti , Marco; Hasenauer , Hubert; Moreno , Adam; Knohl , Alexander; Matteucci , Giorgio; Pilegaard , Kim; Granier , André; Longdoz , Bernard; Maselli , Fabio

    2016-01-01

    Key message A daily 1-km Pan-European weather dataset can drive the BIOME-BGC model for the estimation of current and future beech gross primary production (GPP). Annual beech GPP is affected primarily by spring temperature and more irregularly by summer water stress. [br/] Context The spread of beech forests in Europe enhances the importance of modelling and monitoring their growth in view of ongoing climate changes. [br/] Aims The current paper assesses the capability o...

  3. Proximate content and lipid profile of seeds from Rapanea melanophloeos (The Cape Beech) tree

    International Nuclear Information System (INIS)

    Lotier, N.; Chivandi, E.; Lembede, B.W.; Ibrahim, K.G.; Nyakudya, T.T.

    2017-01-01

    Rapanea melanophloeos(Cape beech)is a fruit-bearing tree indigenous to Southern Africa which produces edible fruit. Seed samples obtained from ripe fruit of the Cape beech trees had their proximate analysis and lipid profiling done. The dry matter and ash contributed 91.29 +- 0.00 %, 1.50 +- 0.01 % of the mass of the seed. Whilst the other proximate analytes namely crude fibre, crude protein and ether extract made up 5.71 +- 0.43 %, 10.50 +- 0.49 % and 4.75 +- 0.09 percentage of the mass of the seeds respectively. The fatty acid profile of the seed oil revealed Linoleic acid (50.43 +- 0.38 %) to be the most dominant. R. melanophloeos seeds are not a viable source of nutrients. (author)

  4. Enzymatic saccharification of hemicellulose obtained from hydrothermally pretreated sugar can bagasse and beech bark

    Energy Technology Data Exchange (ETDEWEB)

    Walch, E; Zemann, A; Bonn, G; Bobleter, O [Innsbruck Univ. (Austria). Inst. fuer Radiochemie und Angewandte Physikalische Chemie; Schinner, F [Innsbruck Univ. (AT). Inst. for Microbiology

    1992-01-01

    Characteristics of different xylanses and their use in the saccharification of sugar cane bagasse and beech bark were studied. Bagasse was pretreated by two different hydrothermolysis procedures, a recirculation and a direct flow-through process. The recirculation procedure resulted in a higher yield of dry matter in the hydrothermolysis solution and a higher saccharification effect after enzymatic hydrolysis. In the case of beech bark, the tannins have first to be removed at temperatures of 120-140{sup o}C. In a second hydrothermal step (at approximately 200{sup o}C), a hemicellulose solution is obtained which can be saccharified enzymatically with high yields. The inhibitory effect of the tannins is experimentally demonstrated. (author).

  5. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    DEFF Research Database (Denmark)

    Van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka

    2017-01-01

    and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light......, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances...... be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species. Light is an important environmental factor controlling biogenic...

  6. Mass Mortality of Beech (Fagus sylvatica in South-West Hungary

    Directory of Open Access Journals (Sweden)

    MOLNÁR, M

    2009-01-01

    Full Text Available The mass mortality of beech (Fagus sylvatica L. in Hungary, which started in 2003 andwent on through 2004, is the result of a typical damage chain. Mortality appeared first of all in beechforests close or outside of its native distribution area. The most significant reason was the droughtperiod from 2000 to 2004, which weakened the trees, and favoured the development of different pestsand pathogens. Characteristic symptoms were frequent at stand margins and in stands thinned forregeneration. The direct causes of the mortality were insects, the green jewel beetle (Agrilus viridisand the beech bark beetle (Taphrorychus bicolor as well as the fungus species Biscogniauxianummularia. With the improvement of weather conditions a continuous recovery of the stands hasbeen observed since 2005.

  7. Adaptation of European beech (Fagus silvatica L.) to different ecological conditions: leaf size variation

    International Nuclear Information System (INIS)

    Barna, M.

    2004-01-01

    In beech trees, both leaf morphology and leaf area show considerable adaptation capabilities to the local radiation climate. The plants adapting to shade conditions create large leaf area with high chlorophyll concentration and high water content in the living tissues. On the other hand, the leaves of plants exposed to radiation of higher intensity have smaller area, several layers of mesophyll, thick epidermis and cuticle, higher dry weight, higher energy potential of the dry mass and several other characteristic properties

  8. Anthropogenic nitrogen deposition alters growth responses of European beech (Fagus sylvativa L.) to climate change.

    Science.gov (United States)

    Hess, Carsten; Niemeyer, Thomas; Fichtner, Andreas; Jansen, Kirstin; Kunz, Matthias; Maneke, Moritz; von Wehrden, Henrik; Quante, Markus; Walmsley, David; von Oheimb, Goddert; Härdtle, Werner

    2018-02-01

    Global change affects the functioning of forest ecosystems and the services they provide, but little is known about the interactive effects of co-occurring global change drivers on important functions such as tree growth and vitality. In the present study we quantified the interactive (i.e. synergistic or antagonistic) effects of atmospheric nitrogen (N) deposition and climatic variables (temperature, precipitation) on tree growth (in terms of tree-ring width, TRW), taking forest ecosystems with European beech (Fagus sylvatica L.) as an example. We hypothesised that (i) N deposition and climatic variables can evoke non-additive responses of the radial increment of beech trees, and (ii) N loads have the potential to strengthen the trees' sensitivity to climate change. In young stands, we found a synergistic positive effect of N deposition and annual mean temperature on TRW, possibly linked to the alleviation of an N shortage in young stands. In mature stands, however, high N deposition significantly increased the trees' sensitivity to increasing annual mean temperatures (antagonistic effect on TRW), possibly due to increased fine root dieback, decreasing mycorrhizal colonization or shifts in biomass allocation patterns (aboveground vs. belowground). Accordingly, N deposition and climatic variables caused both synergistic and antagonistic effects on the radial increment of beech trees, depending on tree age and stand characteristics. Hence, the nature of interactions could mediate the long-term effects of global change drivers (including N deposition) on forest carbon sequestration. In conclusion, our findings illustrate that interaction processes between climatic variables and N deposition are complex and have the potential to impair growth and performance of European beech. This in turn emphasises the importance of multiple-factor studies to foster an integrated understanding and models aiming at improved projections of tree growth responses to co-occurring drivers

  9. H and Al ionic toxicity in seedlings of spruce and beech trees

    Energy Technology Data Exchange (ETDEWEB)

    Rost-Siebert, K.

    1985-01-01

    The influence of aluminium and hydrogen on seedlings of spruce and beech trees was tested. Parameters as root growth, state of health, minerals content and production of dry matter were measured. The results are discussed and show that ion concentrations of hydrogen and aluminium, average for todays forest soils, reduce root growth, damage roots and disturb the uptake of Ca/sup 2+/ and Mg/sup 2+/.

  10. Canopy transpiration of pure and mixed forest stands with variable abundance of European beech

    Science.gov (United States)

    Gebauer, Tobias; Horna, Viviana; Leuschner, Christoph

    2012-06-01

    SummaryThe importance of tree species identity and diversity for biogeochemical cycles in forests is not well understood. In the past, forestry has widely converted mixed forests to pure stands while contemporary forest policy often prefers mixed stands again. However, the hydrological consequences of these changes remain unclear. We tested the hypotheses (i) that significant differences in water use per ground area exist among the tree species of temperate mixed forests and that these differences are more relevant for the amount of stand-level canopy transpiration (Ec) than putative complementarity effects of tree water use, and (ii) that the seasonal patterns of Ec in mixed stands are significantly influenced by the identity of the present tree species. We measured xylem sap flux during 2005 (average precipitation) and 2006 (relatively dry) synchronously in three nearby old-growth forest stands on similar soil differing in the abundance of European beech (pure beech stand, 3-species stand with 70% beech, 5-species stand with sapwood area basis, reflecting a considerable variation in hydraulic architecture and leaf conductance regulation among the co-existing species. Moreover, transpiration per crown projection area (ECA) also differed up to 5-fold among the different species in the mixed stands, probably reflecting contrasting sapwood/crown area ratios. We conclude that Ec is not principally higher in mixed forests than in pure beech stands. However, tree species-specific traits have an important influence on the height of Ec and affect its seasonal variation. Species with a relatively high ECA (notably Tilia) may exhaust soil water reserves early in summer, thereby increasing drought stress in dry years and possibly reducing ecosystem stability in mixed forests.

  11. Decomposition, nitrogen and phosphorus mineralization from beech leaf litter colonized with ectomycorrhizal or litter decomposing basidiomycetes

    OpenAIRE

    COLPAERT, Jan; VAN TICHELEN, Katia

    1996-01-01

    The decomposition and the nitrogen and phosphorus mineralization of fresh beech (Fagus sylvatica L.) leaf litter are described. Leaves were buried for up to 6 months in plant containers in which Scots pine (Pinus sylvestris L.) seedlings were cultivated at a low rate of nutrient addition. The saprotrophic abilities of three ectomycorrhizal fungi, Thelephora terrestris Ehrh.: Fr., Suillus bovinus (L.: Fr.) O. Kuntze and Paxillus involutes (Batsch: Fr) Fr., were compared with the degradation ca...

  12. Periodontal regeneration around natural teeth.

    Science.gov (United States)

    Garrett, S

    1996-11-01

    1. Evidence is conclusive (Table 2) that periodontal regeneration in humans is possible following the use of bone grafts, guided tissue regeneration procedures, both without and in combination with bone grafts, and root demineralization procedures. 2. Clinically guided tissue regeneration procedures have demonstrated significant positive clinical change beyond that achieved with debridement alone in treating mandibular and maxillary (buccal only) Class II furcations. Similar data exist for intraosseous defects. Evidence suggests that the use of bone grafts or GTR procedures produce equal clinical benefit in treating intraosseous defects. Further research is necessary to evaluate GTR procedures compared to, or combined with, bone grafts in treating intraosseous defects. 3. Although there are some data suggesting hopeful results in Class II furcations, the clinical advantage of procedures combining present regenerative techniques remains to be demonstrated. Additional randomized controlled trials with sufficient power are needed to demonstrate the potential usefulness of these techniques. 4. Outcomes following regenerative attempts remain somewhat variable with differences in results between studies and individual subjects. Some of this variability is likely patient related in terms of compliance with plaque control and maintenance procedures, as well as personal habits; e.g., smoking. Variations in the defects selected for study may also affect predictability of outcomes along with other factors. 5. There is evidence to suggest that present regenerative techniques lead to significant amounts of regeneration at localized sites on specific teeth. However, if complete regeneration is to become a reality, additional stimuli to enhance the regenerative process are likely needed. Perhaps this will be accomplished in the future, with combined procedures that include appropriate polypeptide growth factors or tissue factors to provide additional stimulus.

  13. The role of extreme drought events in modelling the distribution of beech at its xeric limit

    Science.gov (United States)

    Rasztovits, Ervin; Berki, Imre; Eredics, Attila; Móricz, Norbert

    2014-05-01

    Context: Projections of species distribution models (SDMs) for future climate conditions are based on long term mean climate data. For management and conservation issues SDMs have been extensively used, but it is not tested whether models that are successful in predicting current distributions are equally powerful in predicting distributions under future climates. Methods: Observations after 2003 confirms that extreme drought events played an important role in driving beech mortality at low-elevation xeric limits. The objective of this study was (1) to set up a simple extreme drought event based vitality model (EDM) using sanitary logging information as a proxy of vitality response of beech and (2) to compare the spatial pattern of the predicted vitality loss provided by the EDM with the distribution limits of the SDMs for three terms (2025, 2050 and 2100) in Hungary to assess model performance. Results: Prediction for vitality loss for 2025 obtained from the EDM was in agreement with those of the SDM, but for the end of the century the EDM predicted a more serious decline in almost all regions of Hungary. Conclusion: The result of the comparison suggests that the increasing frequency and severity of extremes might play a more important role in limiting the distribution of beech in the future near to the xeric limit than long-term means.

  14. Influence of steaming on drying quality and colour of beech timber

    Directory of Open Access Journals (Sweden)

    Milić Goran

    2015-01-01

    Full Text Available This paper presents the results of an analysis of influence of the “light” steaming process on conventional drying and colour of beech timber. A stack consisting of steamed and unsteamed boards was dried. Moisture content and moisture content profiles were recorded, and at the end of drying final moisture content, moisture content difference across thickness, case-hardening and colour were determinated. No statistically significant difference between steamed and unsteamed timber was established in any of the examined parameters (MC, ΔMC, gap. The results indicate that equal (or even better drying quality can be expected with steamed beech timber than with unsteamed timber, given the same drying schedule. Dry steamed timber was darker and more reddish than the unsteamed one. An imprecision of measurement by probes in the kiln was noticed in measuring steamed and unsteamed beech timber having a moisture content of between 7% and 15%, and a solution for overcoming this problem was given. [Projekat Ministarstva nauke Republike Srbije, br. TR 31041

  15. On marginal regeneration

    NARCIS (Netherlands)

    Stein, H.N.

    1991-01-01

    On applying the marginal regeneration concept to the drainage of free liquid films, problems are encountered: the films do not show a "neck" of minimum thickness at the film/border transition; and the causes of the direction dependence of the marginal regeneration are unclear. Both problems can be

  16. Reduce, reuse, recycle - Developmental signals in spinal cord regeneration.

    Science.gov (United States)

    Cardozo, Marcos Julian; Mysiak, Karolina S; Becker, Thomas; Becker, Catherina G

    2017-12-01

    Anamniotes, fishes and amphibians, have the capacity to regenerate spinal cord tissue after injury, generating new neurons that mature and integrate into the spinal circuitry. Elucidating the molecular signals that promote this regeneration is a fundamental question in regeneration research. Model systems, such as salamanders and larval and adult zebrafish are used to analyse successful regeneration. This shows that many developmental signals, such as Notch, Hedgehog (Hh), Bone Morphogenetic Protein (BMP), Wnt, Fibroblast Growth Factor (FGF), Retinoic Acid (RA) and neurotransmitters are redeployed during regeneration and activate resident spinal progenitor cells. Here we compare the roles of these signals in spinal cord development and regeneration of the much larger and fully patterned adult spinal cord. Understanding how developmental signalling systems are reactivated in successfully regenerating species may ultimately lead to ways to reactivate similar systems in mammalian progenitor cells, which do not show neurogenesis after spinal injury. Copyright © 2017. Published by Elsevier Inc.

  17. Beech Fructification and Bank Vole Population Dynamics--Combined Analyses of Promoters of Human Puumala Virus Infections in Germany.

    Directory of Open Access Journals (Sweden)

    Daniela Reil

    Full Text Available The transmission of wildlife zoonoses to humans depends, amongst others, on complex interactions of host population ecology and pathogen dynamics within host populations. In Europe, the Puumala virus (PUUV causes nephropathia epidemica in humans. In this study we investigated complex interrelations within the epidemic system of PUUV and its rodent host, the bank vole (Myodes glareolus. We suggest that beech fructification and bank vole abundance are both decisive factors affecting human PUUV infections. While rodent host dynamics are expected to be directly linked to human PUUV infections, beech fructification is a rather indirect predictor by serving as food source for PUUV rodent hosts. Furthermore, we examined the dependence of bank vole abundance on beech fructification. We analysed a 12-year (2001-2012 time series of the parameters: beech fructification (as food resource for the PUUV host, bank vole abundance and human incidences from 7 Federal States of Germany. For the first time, we could show the direct interrelation between these three parameters involved in human PUUV epidemics and we were able to demonstrate on a large scale that human PUUV infections are highly correlated with bank vole abundance in the present year, as well as beech fructification in the previous year. By using beech fructification and bank vole abundance as predictors in one model we significantly improved the degree of explanation of human PUUV incidence. Federal State was included as random factor because human PUUV incidence varies considerably among states. Surprisingly, the effect of rodent abundance on human PUUV infections is less strong compared to the indirect effect of beech fructification. Our findings are useful to facilitate the development of predictive models for host population dynamics and the related PUUV infection risk for humans and can be used for plant protection and human health protection purposes.

  18. Resilient Leaf Physiological Response of European Beech (Fagus sylvatica L. to Summer Drought and Drought Release

    Directory of Open Access Journals (Sweden)

    Ellen E. Pflug

    2018-02-01

    Full Text Available Drought is a major environmental constraint to trees, causing severe stress and thus adversely affecting their functional integrity. European beech (Fagus sylvatica L. is a key species in mesic forests that is commonly expected to suffer in a future climate with more intense and frequent droughts. Here, we assessed the seasonal response of leaf physiological characteristics of beech saplings to drought and drought release to investigate their potential to recover from the imposed stress and overcome previous limitations. Saplings were transplanted to model ecosystems and exposed to a simulated summer drought. Pre-dawn water potentials (ψpd, stomatal conductance (gS, intercellular CO2 concentration (ci, net-photosynthesis (AN, PSII chlorophyll fluorescence (PItot, non-structural carbohydrate concentrations (NSC; soluble sugars, starch and carbon isotope signatures were measured in leaves throughout the growing season. Pre-dawn water potentials (ψpd, gS, ci, AN, and PItot decreased as drought progressed, and the concentration of soluble sugars increased at the expense of starch. Carbon isotopes in soluble sugars (δ13CS showed a distinct increase under drought, suggesting, together with decreased ci, stomatal limitation of AN. Drought effects on ψpd, ci, and NSC disappeared shortly after re-watering, while full recovery of gS, AN, and PItot was delayed by 1 week. The fast recovery of NSC was reflected by a rapid decay of the drought signal in δ13C values, indicating a rapid turnover of assimilates and a reactivation of carbon metabolism. After recovery, the previously drought-exposed saplings showed a stimulation of AN and a trend toward elevated starch concentrations, which counteracted the previous drought limitations. Overall, our results suggest that the internal water relations of beech saplings and the physiological activity of leaves are restored rapidly after drought release. In the case of AN, stimulation after drought may partially

  19. Effect of the silvicultural treatment on canopy properties, litter and seed production in beech coppices under conversion to high forest.

    Directory of Open Access Journals (Sweden)

    Andrea Cutini

    2010-12-01

    Full Text Available European beech (Fagus sylvatica L. is widely distributed in Italy where it covers 1035103 ha, mainly concentrated in the mountainous areas at altitudes above 900 m. The major part is represented by high forest often issued from the conversion of coppice woods, which in the past was the silvicultural system most widely applied mainly to provide fire wood. The social changes occurred in the second half of the last century –fire wood market crisis and the increasing importance of environmental issues- enhanced the conversion into high forest of large areas previously managed as coppice by means of different silvicultural treatments and practices. Nevertheless, the environmental benefits of this choice were not adequately investigated. Results of annual measurements (1992-2009 made in a beech coppice stand aged 65 are here reported. The study area is located on the Alpe di Catenaia, a pre-Apennine outcrop close to Arezzo (Central Italy. Variables strictly related to stand productivity and dynamics such as annual litter and seed production, leaf area index (LAI and transmittance (PAR were measured in the research area of Buca Zamponi to estimate the effects of two theses, natural evolution (TEST and conversion into high forest (DIR. Three thinnings were undertaken in the latter thesis in 1972, 1987 and 2002. Additional theses of natural evolution (CONTR and advance seed cutting (TS were added in 2002 in a nearby study area (Eremo della Casella. Results showed the high productivity of coppice stands, under conversion to high forest, with mean values of annual total litter, leaf litter and leaf area index of 5 Mg ha-1, 3 Mg ha-1 and 6 m2m-2, respectively. These findings confirm both the prompt response of beech to intensive thinning cycles and the reliability of undertaking coppice conversion into high forest. Furthermore, the positive trend observed in the ecological parameters and the high consistency of leaf fraction, highlight the still juvenile

  20. Eddy-covariance methane flux measurements over a European beech forest

    Science.gov (United States)

    Gentsch, Lydia; Siebicke, Lukas; Knohl, Alexander

    2015-04-01

    The role of forests in global methane (CH4) turnover is currently not well constrained, partially because of the lack of spatially integrative forest-scale measurements of CH4 fluxes. Soil chamber measurements imply that temperate forests generally act as CH4 sinks. Upscaling of chamber observations to the forest scale is however problematic, if the upscaling is not constrained by concurrent 'top-down' measurements, such as of the eddy-covariance type, which provide sufficient integration of spatial variations and of further potential CH4 flux components within forest ecosystems. Ongoing development of laser absorption-based optical instruments, resulting in enhanced measurement stability, precision and sampling speed, has recently improved the prospects for meaningful eddy-covariance measurements at sites with presumably low CH4 fluxes, hence prone to reach the flux detection limit. At present, we are launching eddy-covariance CH4 measurements at a long-running ICOS flux tower site (Hainich National Park, Germany), located in a semi natural, unmanaged, beech dominated forest. Eddy-covariance measurements will be conducted with a laser spectrometer for parallel CH4, H2Ov and CO2 measurements (FGGA, Los Gatos Research, USA). Independent observations of the CO2 flux by the FGGA and a standard Infrared Gas Analyser (LI-7200, LI-COR, USA) will allow to evaluate data quality of measured CH4 fluxes. Here, we want to present first results with a focus on uncertainties of the calculated CH4 fluxes with regard to instrument precision, data processing and site conditions. In future, we plan to compare eddy-covariance flux estimates to side-by-side turbulent flux observations from a novel eddy accumulation system. Furthermore, soil CH4 fluxes will be measured with four automated chambers situated within the tower footprint. Based on a previous soil chamber study at the same site, we expect the Hainich forest site to act as a CH4 sink. However, we hypothesize that our

  1. Desiccation and Mortality Dynamics in Seedlings of Different European Beech (Fagus sylvatica L.) Populations under Extreme Drought Conditions

    Science.gov (United States)

    Bolte, Andreas; Czajkowski, Tomasz; Cocozza, Claudia; Tognetti, Roberto; de Miguel, Marina; Pšidová, Eva; Ditmarová, Ĺubica; Dinca, Lucian; Delzon, Sylvain; Cochard, Hervè; Ræbild, Anders; de Luis, Martin; Cvjetkovic, Branislav; Heiri, Caroline; Müller, Jürgen

    2016-01-01

    European beech (Fagus sylvatica L., hereafter beech), one of the major native tree species in Europe, is known to be drought sensitive. Thus, the identification of critical thresholds of drought impact intensity and duration are of high interest for assessing the adaptive potential of European beech to climate change in its native range. In a common garden experiment with one-year-old seedlings originating from central and marginal origins in six European countries (Denmark, Germany, France, Romania, Bosnia-Herzegovina, and Spain), we applied extreme drought stress and observed desiccation and mortality processes among the different populations and related them to plant water status (predawn water potential, ΨPD) and soil hydraulic traits. For the lethal drought assessment, we used a critical threshold of soil water availability that is reached when 50% mortality in seedling populations occurs (LD50SWA). We found significant population differences in LD50SWA (10.5–17.8%), and mortality dynamics that suggest a genetic difference in drought resistance between populations. The LD50SWA values correlate significantly with the mean growing season precipitation at population origins, but not with the geographic margins of beech range. Thus, beech range marginality may be more due to climatic conditions than to geographic range. The outcome of this study suggests the genetic variation has a major influence on the varying adaptive potential of the investigated populations. PMID:27379105

  2. 'Nikkei Global Environment Technology Prize' awarded to the joint research group on regeneration of tropical forest; Nettairin saisei kyodo kenkyu ga 'Nikkei chikyu kankyo gijutsusho' wo jusho

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1998-11-10

    The tropical forest regeneration technology research group of Kansai Electric Power Company and Kansai Environment Center has been performing the research and development of tropical forest regeneration technology jointly with Indonesia since fiscal 1992. The group was awarded with the Global Environment Technology Prize from Nihon Keizai Shimbun, Inc. As a result of stringent examination on 97 applications, being two times as many as in usual years, the group received high evaluation on the originality, reality and possibility of proliferation of its research, and impacts given to the societies. Two other groups were also selected. The achievements were reported by the representative of the group in the award commemoration lecture at the global environment economist summit held by the Nikkei press the same day. Conventionally, afforestation done with considerable efforts has often been lost by forest fires and slash-and-burn farming, whereas the present research aims at establishing a comprehensive afforestation technology considering social and economic aspects, and CO2 fixation. As one of the choices of flexible measures as a result of the effect of forests having been recognized in COP3, frameworks for utilizing the mechanisms of joint implementation and clean resource development were introduced. Ever increasing expectations are placed on the achievements of the present research works. (NEDO)

  3. Biological regeneration of phenol-loaded activated carbon (up flow system)

    International Nuclear Information System (INIS)

    Durrani, M.A.Q.J.; Mirajuddin; Martin, R.J.

    1995-01-01

    This paper represents the report on the biological regeneration of totally activated carbon following the experimental studies carried out at the University of Birmingham, U.K. Biological regeneration is one of several methods that may be used to restore the adsorptive capacity of exhausted granular activated carbon. This study deals with in situ biological regeneration on a pilot scale. The principal objective of this research was to ascertain whether biological regeneration of GAC could occur under conditions typical of water treatment. The important parameters which may have the greatest impact on bio regeneration for a given adsorbate were studied. The research investigated the extent of bio regeneration for phenol of concentration 50 mg/l. Bio regeneration in the total exhaustion system was evaluated in terms of regeneration efficiency and the substrate removal. A three mode procedure was followed for each bio regeneration run. The prepared carbon was initialing exhausted with an adsorbate; it was then bio regenerated with a mixed culture of bacteria, and lastly the carbon was saturated. In the totally exhausted GAC system, the bio regeneration was enhanced by increasing the duration of regeneration for a fixed initial biomass content of the bioreactor. The regenerated phenol loaded GAC bed had nearly gained its original adsorption after the 5-day period of regeneration. Bacterial counts in the effluents of regenerated GAC columns were significantly more than those of fresh carbon effluents. (author)

  4. Desiccation and Mortality Dynamics in Seedlings of Different European Beech (Fagus sylvatica L.) Populations under Extreme Drought Conditions

    DEFF Research Database (Denmark)

    Bolte, Andreas; Czajkowski, Tomasz; Cocozza, Claudia

    2016-01-01

    European beech (Fagus sylvatica L., hereafter beech), one of the major native tree species in Europe, is known to be drought sensitive. Thus, the identification of critical thresholds of drought impact intensity and duration are of high interest for assessing the adaptive potential of European...

  5. Effect of tin oxide nano particles and heat treatment on decay resistance and physical properties of beech wood (Fagus orientalis

    Directory of Open Access Journals (Sweden)

    Maryam Ghorbani

    2014-11-01

    Full Text Available This research was conducted to investigate the effect of Tin oxide nanoparticles and heat treatment on decay resistance and physical properties of beech wood. Biological and physical test samples were prepared according to EN-113 and ASTM-D4446-05 standards respectively. Samples were classified into 4 groups: control, impregnation with Tin oxide nanoparticles, heat treatment and nano-heat treatment. Impregnation with Tin oxide nano at 5000ppm concentration was carried out in the cylinder according to Bethell method. Then, samples were heated at 140, 160 and 185˚C for 2 and 4 hours. According to results, decay resistance improved with increasing time and temperature of heat treatment. Least weight loss showed 46.39% reduction in nano-heat samples treated at 180˚C for 4 hours in comparison with control at highest weight loss. Nano-heat treated samples demonstrated the maximum amount of water absorption without significant difference with control and nanoparticles treated samples. Increase in heat treatment temperature reduced water absorption so that it is revealed 47.8% reduction in heat treated samples at 180°C for 4h after 24h immersion in water. In nano-heat treated samples at 180˚C for 2h was measured least volume swelling. Volume swelling in nano-treated samples decreased 8.7 and 22.76% after 2 and 24 h immersion in comparison with the control samples respectively.

  6. Effect of heat-treatment with raw cotton seed oil on decay resistance and dimensional stability of Beech (Fagus orientalis

    Directory of Open Access Journals (Sweden)

    مریم قربانی

    2015-05-01

    Full Text Available This research was conducted to determine the effect of heat-treatment with raw cotton seed oil on decay resistance and dimensional stability of beech according to EN113 and ASTM-D1037 standards respectively. The heat treatment with raw cotton seed oil was carried out in the cylinder at the temperatures of 130 and 170oC for 30 and 60 minutes. Oil uptake, density, volumetric swelling, water absorption and weight loss exposed to decay were measured. Oil uptake at 30 and 60 min were determined 10.5 and 13.3 Kg/cm3 respectively. Oil-heat treated samples at 30min and 130°C indicated the maximum density with 87.7% increase. According to results, oil-heat treatment improved water repellency and dimensional stability. Water absorption in 130°C and 60 minutes decreased 76% in comparison with control. Decay resistance of oil soaked samples for 60minutes was 80.2% more than control samples. Oil-heat treatment compared with oil treatment improved decay resistance, this effect was significant at 30 min. The temperature rise of oil–heat treatment at 30 minutes improved decay resistance, but the improvement under same level of temperature with increase time was not significant.

  7. Helping the Retina Regenerate

    Science.gov (United States)

    ... the retina News Brief 03/30/17 A new report gives recommendations for regenerating retinal ganglion cells (RGCs), crucial neurons in the back of the eye that carry visual information to the brain. Authored ...

  8. Axonal Regeneration in Mammals with Spinal Cord Injury

    Science.gov (United States)

    1983-09-14

    Cajal, S. 1905. Notas preventivas sobre la degeneracion y regeneracion las vias nerviosos centrales . Trab. Lab. Invest. Biol. Univ. Madrid, 4: 295-301...S. 1914. Degeneracion y Regeneration del Sistema Nervioso , Vol. 1, 2. (Nicolas Moya, Madrid), Ramon y Cajal, S. 1928. Degeneration and Regeneration...field of central nervous system (CNS) regeneration research. These developments have revealed important aspects regarding the histology and

  9. Some clastic rocks as parent rocks in beech forests of Brezovica - Južni Kučaj

    Directory of Open Access Journals (Sweden)

    Joksimović Vesna

    2003-01-01

    Full Text Available On the large forest areas, where the measures of soil quality improvement are absent or rarely undertaken, the rocks are the sources of a great number of elements in plant nutrition and one of the factors affecting the contents of some elements in plants. The aim of the study is to determine the differences in the contents of Cu, Zn, Mn, Ni, Fe, Cd, Co, Pb and Cr in the beech leaves developed in the same climate conditions, on morphologically similar terrains, composed of different types of sedimentary rocks. This paper presents the study results of the contents of the above elements in argillites, sandstones (grauwackes and microconglomerates occurring as the parent rocks in high beech forests in the region of GJ Bogovina (Brezovica Južni Kučaj and in the leaves of beech developed on these rocks.

  10. Contributions to the phytocoenologic study in pure european beech stand forests in Codru-Moma Mountains (North-Western Romania

    Directory of Open Access Journals (Sweden)

    Călin-Gheorghe PĂŞCUŢ

    2010-05-01

    Full Text Available In the present work we present a phytocoenologic study on the associations found in pure European beech stand forests in Codru-Moma Mountains namely: Festuco drymejae-Fagetum Morariu et al. 1968, Luzulo albidae-Fagetum sylvaticae Zólyomi 1955.Characterization of the associations we studied and presentation of the tables have been made considering the selection of the most representative relevées of pure European beech forests belonging to Codru-Moma Mountains.The phytocoenoses of pure forest stands of European beech forests belonging to the two associations were analyzed in terms of floristic composition, life forms spectrum, spectrum chart of the floral elements and ecological indices.

  11. Effect of CO2 enhancement on beech (Fagus sylvatica L. seedling root rot due to Phytophthora plurivora and Phytophthora cactorum

    Directory of Open Access Journals (Sweden)

    Tkaczyk Miłosz

    2014-09-01

    Full Text Available Global climate change is associated with higher concentrations of atmospheric carbon dioxide (CO2. The ongoing changes are likely to have significant, direct or indirect effects on plant diseases caused by many biotic agents such as phytopathogenic fungi. This study results showed that increased CO2 concentration did not stimulate the growth of 1-year-old beech Fagus sylvatica L seedlings but it activated pathogenic Phytophthora species (P. plurivora and P. cactorum which caused significant reduction in the total number of fine roots as well as their length and area. The results of the greenhouse experiment indicated that pathogens once introduced into soil survived in pot soil, became periodically active (in sufficient water conditions and were able to damage beech fine roots. However, the trees mortality was not observed during the first year of experiment. DNA analyses performed on soil and beech tissue proved persistence of introduced Phytophthora isolates.

  12. Social valuation of scenic beauty in Catalonian beech forests; Valoracion social de las propiedades esteticas de los hayedos en Cataluna

    Energy Technology Data Exchange (ETDEWEB)

    Vega-Garcia, C.; Burriel, M.; Alcazar, J.

    2011-07-01

    Methods tested in other countries are applied for scenic beauty valuation in several beech locations in Catalonia including significant differences in site, origin, age and stand structure. The study intends to measure stand scenic beauty as seen from inside the forest, as forest visitors see it (near-view). Assessments are obtained through panels of observers in slide sessions, which are transformed into scaled ratings and related through regression analysis to plot-based forest inventory data. The development of statistical models that describe social visual preferences allows the assessment of the contribution of different forestry-related physical variables to the aesthetic improvement of beech forests. It can also be useful as a guide to beech forest planning where recreational use is prevailing or very important. (Author) 37 refs.

  13. Investigation on the Scratch Strength of Clear Paints Used in Furniture Industries on the Wood Species Beech, Elm, Alder and Spruce

    Directory of Open Access Journals (Sweden)

    Mohammad Ghofrani

    2014-05-01

    Full Text Available In This research, the scratch strength (Cross-Cut Test of clear paints (nitrocellulose lacquers and acid catalyst lacquers of wood species Beech, Elm, Alder and spruce were studied as a function of moisture content (MC of the samples. For this purpose, lumbers (550×110×12 mm were cut from sapwood in tangential surfaces and were air dried for one month according to wood drying procedures. Then, for pre-conditioning of moisture content, at the levels of 8%, 12% and 15%, the samples were placed in three clima rooms. Then, finish applied and strength tests were performed. The results revealed that for acid catalyst lacquers the highest scratch strength (10.4% belongs to Elm wood with 8% moisture content, and the lowest scratch strength (53.6% belongs to Spruce wood with nitrocellulose lacquers having 15% moisture content.

  14. Wood structural differences between northern and southern beech provenances growing at a moderate site.

    Science.gov (United States)

    Eilmann, B; Sterck, F; Wegner, L; de Vries, S M G; von Arx, G; Mohren, G M J; den Ouden, J; Sass-Klaassen, U

    2014-08-01

    Planting provenances originating from southern to northern locations has been discussed as a strategy to speed up species migration and mitigate negative effects of climate change on forest stability and productivity. Especially for drought-susceptible species such as European beech (Fagus sylvatica L.), the introduction of drought-tolerant provenances from the south could be an option. Yet, beech has been found to respond plastically to environmental conditions, suggesting that the climate on the plantation site might be more important for tree growth than the genetic predisposition of potentially drought-adapted provenances. In this study, we compared the radial growth, wood-anatomical traits and leaf phenology of four beech provenances originating from southern (Bulgaria, France) and northern locations (Sweden, the Netherlands) and planted in a provenance trial in the Netherlands. The distribution of precipitation largely differs between the sites of origin. The northern provenances experience a maximum and the southern provenances experience a minimum of rainfall in summer. We compared tree productivity and the anatomy of the water-conducting system for the period from 2000 to 2010, including the drought year 2003. In addition, tree mortality and the timing of leaf unfolding in spring were analysed for the years 2001, 2007 and 2012. Comparison of these traits in the four beech provenances indicates the influence of genetic predisposition and local environmental factors on the performance of these provenances under moderate site conditions. Variation in radial growth was controlled by environment, although the growth level slightly differed due to genetic background. The Bulgarian provenance had an efficient water-conducting system which was moreover unaffected by the drought in 2003, pointing to a high ability of this provenance to cope well with dry conditions. In addition, the Bulgarian provenance showed up as most productive in terms of height and radial

  15. Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians

    Directory of Open Access Journals (Sweden)

    Mihaela Paucã-Comãnescu

    2009-12-01

    Full Text Available The hill beech forests cover most of the woody area in the Doftana Valley. The present study refers, for the first time, to two beech forests typical to this belt, which belong to the phytocoenological associations Epipactieto-Fagetum (Resmeriţă, 1972, in the Lunca Mare area, and Hieracio rotundati-Fagetum (Vida 1983, Täuber 1987 in the Sotrile area, from floristic, structural, biomass and necromass accumulation point of view, within the framework of the vertical structure of biocoenosis. The limestone substratum, occasionally with small outcrops in the first beech forest, differs chiefly through the pH levels (6.34-5.67 from the siliceous substratum (pH 5.11-4.36 in the second beech forest. The layer of trees is dominated by Fagus sylvatica in both forests; this species is associated with Cerasus avium (4.5%, Acer pseudoplatanus (2% and Sorbus torminalis (2% in the first beech forest, and is monodominant in the second. Although the forest underwent selective cuts, more intense in the Lunca Mare area, the aboveground ligneous biomass reaches nowadays 222 t/ha in the Lunca Mare area compared to only 163 t/ha in the Sotrile area; the average height is 28.8ą2.49 m and 23.7ą1.12 m, respectively, and the diameter is 33.30ą7.9 cm and 31.60ą6.28 cm, respectively. The species of macrofungi, not very numerous during the study because of scarce precipitations (6 and 7 species, respectively, are predominant on the rhytidoma trees in the beech forest rooted on the limestone ground; in the Sotrile beech forest they are joined by mycorrhizal and parasite species. The layer of shrub is underdeveloped. The herbaceous layer is discontinuous, and includes, along herbs, small plants and saplings belonging to the ligneous species and to liana Hedera helix. The maximal value of the aboveground biomass of the layer is 317 kg/ha DM in the Lunca Mare area and 235 kg /ha DM in the Sotrile area. Bryophyta is present in large quantities, especially in the Sotrile

  16. Height-Diameter Models for Mixed-Species Forests Consisting of Spruce, Fir, and Beech

    Directory of Open Access Journals (Sweden)

    Petráš Rudolf

    2014-06-01

    Full Text Available Height-diameter models define the general relationship between the tree height and diameter at each growth stage of the forest stand. This paper presents generalized height-diameter models for mixed-species forest stands consisting of Norway spruce (Picea abies Karst., Silver fir (Abies alba L., and European beech (Fagus sylvatica L. from Slovakia. The models were derived using two growth functions from the exponential family: the two-parameter Michailoff and three-parameter Korf functions. Generalized height-diameter functions must normally be constrained to pass through the mean stand diameter and height, and then the final growth model has only one or two parameters to be estimated. These “free” parameters are then expressed over the quadratic mean diameter, height and stand age and the final mathematical form of the model is obtained. The study material included 50 long-term experimental plots located in the Western Carpathians. The plots were established 40-50 years ago and have been repeatedly measured at 5 to 10-year intervals. The dataset includes 7,950 height measurements of spruce, 21,661 of fir and 5,794 of beech. As many as 9 regression models were derived for each species. Although the “goodness of fit” of all models showed that they were generally well suited for the data, the best results were obtained for silver fir. The coefficient of determination ranged from 0.946 to 0.948, RMSE (m was in the interval 1.94-1.97 and the bias (m was -0.031 to 0.063. Although slightly imprecise parameter estimation was established for spruce, the estimations of the regression parameters obtained for beech were quite less precise. The coefficient of determination for beech was 0.854-0.860, RMSE (m 2.67-2.72, and the bias (m ranged from -0.144 to -0.056. The majority of models using Korf’s formula produced slightly better estimations than Michailoff’s, and it proved immaterial which estimated parameter was fixed and which parameters

  17. Leaf area index from litter collection: impact of specific leaf area variability within a beech stand

    Energy Technology Data Exchange (ETDEWEB)

    Bouriaud, O. [Inst. National de la Recherche Agronomique, Centre de Recherches Forestieres de Nancy, Champenoux (France); Soudani, K. [Univ. Paris-Sud XI, Dept. d' Ecophysiologie Vegetale, Lab. Ecologie Systematique et Evolution, Orsay Cedex (France); Breda, N. [Inst. National de la Recherche Agronomique, Centre de Recherches Forestieres de Nancy, Champenoux (France)

    2003-06-01

    Litter fall collection is a direct method widely used to estimate leaf area index (LAI) in broad-leaved forest stands. Indirect measurements using radiation transmittance and gap fraction theory are often compared and calibrated against litter fall, which is considered as a reference method, but few studies address the question of litter specific leaf area (SLA) measurement and variability. SLA (leaf area per unit of dry weight, m{sup 2}{center_dot}g{sup -1}) is used to convert dry leaf litter biomass (g .m{sup -}2) into leaf area per ground unit area (m{sup 2}{center_dot}m{sup -2}). We paid special attention to this parameter in two young beech stands (dense and thinned) in northeastern France. The variability of both canopy (closure, LAI) and site conditions (soil properties, vegetation) was investigated as potential contributing factors to beech SLA variability. A systematic description of soil and floristic composition was performed and three types of soil were identified. Ellenberg's indicator values were averaged for each plot to assess nitrogen soil content. SLA of beech litter was measured three times during the fall in 23 plots in the stands (40 ha). Litter was collected bimonthly in square-shaped traps (0.5 m{sup 2}) and dried. Before drying, 30 leaves per plot and for each date were sampled, and leaf length, width, and area were measured with the help of a LI-COR areameter. SLA was calculated as the ratio of cumulated leaf area to total dry weight of the 30 leaves. Leaves characteristics per plot were averaged for the three dates of litter collection. Plant area index (PAI), estimated using the LAI-2000 plant canopy analyser and considering only the upper three rings, ranged from 2.9 to 8.1. Specific leaf area of beech litter was also highly different from one plot to the other, ranging from 150 to 320 cm{sup 2}{center_dot}g{sup -1}. Nevertheless, no relationship was found between SLA and stand canopy closure or PAI On the contrary, a significant

  18. Beech and spruce under the influence of electromagnetic radiation by radar

    International Nuclear Information System (INIS)

    Götz, G.; Matyssek, R.; Käs, G.

    2001-01-01

    Throughout a three-year study period beech and spruce trees were examined for potential effects of electromagnetic radiation by radar on the morphological and physiological performance at the crown level. No effects of radar on photosynthesis, transpiration, stomatal regulation as well as twig and foliage differentiation were found in late summer after seasonal exposure to this kind of radiation, when comparing radar-exposed with shielded crown parts. Adverse effects caused by radar on forest trees appear to be unlikely on a short-term scale, given conditions similar to those of this case study [de

  19. Leaf area index from litter collection: impact of specific leaf area variability within a beech stand

    International Nuclear Information System (INIS)

    Bouriaud, O.; Soudani, K.; Breda, N.

    2003-01-01

    Litter fall collection is a direct method widely used to estimate leaf area index (LAI) in broad-leaved forest stands. Indirect measurements using radiation transmittance and gap fraction theory are often compared and calibrated against litter fall, which is considered as a reference method, but few studies address the question of litter specific leaf area (SLA) measurement and variability. SLA (leaf area per unit of dry weight, m 2 ·g -1 ) is used to convert dry leaf litter biomass (g .m - 2) into leaf area per ground unit area (m 2 ·m -2 ). We paid special attention to this parameter in two young beech stands (dense and thinned) in northeastern France. The variability of both canopy (closure, LAI) and site conditions (soil properties, vegetation) was investigated as potential contributing factors to beech SLA variability. A systematic description of soil and floristic composition was performed and three types of soil were identified. Ellenberg's indicator values were averaged for each plot to assess nitrogen soil content. SLA of beech litter was measured three times during the fall in 23 plots in the stands (40 ha). Litter was collected bimonthly in square-shaped traps (0.5 m 2 ) and dried. Before drying, 30 leaves per plot and for each date were sampled, and leaf length, width, and area were measured with the help of a LI-COR areameter. SLA was calculated as the ratio of cumulated leaf area to total dry weight of the 30 leaves. Leaves characteristics per plot were averaged for the three dates of litter collection. Plant area index (PAI), estimated using the LAI-2000 plant canopy analyser and considering only the upper three rings, ranged from 2.9 to 8.1. Specific leaf area of beech litter was also highly different from one plot to the other, ranging from 150 to 320 cm 2 ·g -1 . Nevertheless, no relationship was found between SLA and stand canopy closure or PAI On the contrary, a significant relationship between SLA and soil properties was observed. Both SLA

  20. Thermal and Structural Analysis of Micro-Fabricated Involute Regenerators

    Science.gov (United States)

    Qiu, Songgang; Augenblick, Jack E.

    2005-02-01

    Long-life, high-efficiency power generators based on free-piston Stirling engines are an energy conversion solution for future space power generation and commercial applications. As part of the efforts to further improve Stirling engine efficiency and reliability, a micro-fabricated, involute regenerator structure is proposed by a Cleveland State University-led regenerator research team. This paper reports on thermal and structural analyses of the involute regenerator to demonstrate the feasibility of the proposed regenerator. The results indicate that the involute regenerator has extremely high axial stiffness to sustain reasonable axial compression forces with negligible lateral deformation. The relatively low radial stiffness may impose some challenges to the appropriate installation of the in-volute regenerators.

  1. Perfluorodecalin and bone regeneration

    Directory of Open Access Journals (Sweden)

    F Tamimi

    2013-01-01

    Full Text Available Perfluorodecalin (PFD is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

  2. Bone regeneration and stem cells

    Science.gov (United States)

    Arvidson, K; Abdallah, B M; Applegate, L A; Baldini, N; Cenni, E; Gomez-Barrena, E; Granchi, D; Kassem, M; Konttinen, Y T; Mustafa, K; Pioletti, D P; Sillat, T; Finne-Wistrand, A

    2011-01-01

    Abstract This invited review covers research areas of central importance for orthopaedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and foetal stem cells, effects of sex steroids on mesenchymal stem cells, use of platelet-rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed. PMID:21129153

  3. Bone regeneration and stem cells

    DEFF Research Database (Denmark)

    Arvidson, K; Abdallah, B M; Applegate, L A

    2011-01-01

    cells, use of platelet rich plasma for tissue repair, osteogenesis and its molecular markers. A variety of cells in addition to stem cells, as well as advances in materials science to meet specific requirements for bone and soft tissue regeneration by addition of bioactive molecules, are discussed.......This invited review covers research areas of central importance for orthopedic and maxillofacial bone tissue repair, including normal fracture healing and healing problems, biomaterial scaffolds for tissue engineering, mesenchymal and fetal stem cells, effects of sex steroids on mesenchymal stem...

  4. A comparative study of regenerated bamboo, cotton and viscose ...

    African Journals Online (AJOL)

    Very little information is available about the validation of these properties through scientific research studies. It is also evident that information about natural bamboo and regenerated bamboo fibre products is often confusing. Regenerated bamboo (also referred to as bamboo viscose or bamboo rayon) is manufactured from ...

  5. Plant biodiversity of beech forests in central-northern Italy: a methodological approach for conservation purposes

    Directory of Open Access Journals (Sweden)

    Marcantonio M

    2012-07-01

    Full Text Available Forests are reckoned essentials as biodiversity reservoirs and carbon sinks. Current threats to forest ecosystems (e.g., climate changes, habitat loss and fragmentation, management changes call for monitoring their biodiversity and preserving their ecological functions. In this study, we characterized plants diversity of five beech forests located in central and north Apennines mountain chain, using results by a probabilistic sampling. In order to achieve our goals, we have considered species richness and abundance, taxonomic distinctness and species composition, using both old and new analytical approaches. Results have shown how: (1 the forest type dominated by Fagus sylvatica is characterized by high complexity, with marked compositional, structural and biodiversity differences; (2 beech forests of Pigelleto di Piancastagnaio and Valle della Corte show the highest plants diversity values. The ecological characteristics of these areas, which sustain high diversity values, are unique and of great conservation interest; (3 the use of species richness as the only diversity measure have not allowed an efficient differentiation between studied areas. Indeed, the use of different indexes and analytical methods is required to detect multiple characteristics of biological diversity, as well as to carry out efficient biodiversity surveys aimed to develop optimal conservation strategies. In the future, we plan to apply the sampling methodology and the analytical approach used in this paper to characterize plants diversity of similar forest types.

  6. Impact of windstorm on a community of centipedes (Chilopoda) in a beech forest in Western Poland.

    Science.gov (United States)

    Leśniewska, Małgorzata; Skwierczyński, Filip

    2018-01-01

    The study was carried out in the years 2016-2017, five years after a windstorm which destroyed 1/3 of the protected beech forest area in the west of Poland. The community of centipedes in the area affected by the windstorm was depleted in terms of the species richness, diversity, and population density. The dominance structures were shortened and the species composition was rebuilt. The areas that proved to be the richest in terms of species richness and diversity among the sites affected by the windstorm were the one where windfallen trees were left and the other where beech trees had been planted by humans. In total, the quantitative and qualitative samples collected four times throughout a year featured 608 specimens from 11 species of two centipede orders - Lithobiomorpha and Geophilomorpha. Lithobius curtipes and L. forficatus were found in all of the investigated areas. L. pelidnus and L. piceus were captured at control sites exclusively. Only one species - L. erythrocephalus was found solely at the damaged site. The most numerous and most frequently found species in the community were L. curtipes , L. mutabilis , and Strigamia acuminata respectively. Although windstorms are natural phenomena their consequences may lead to significant changes in the community of the investigated soil animals. The importance of coarse woody debris, significantly contributing to the improvement and maintenance of species richness and diversity of Chilopoda, has once again been confirmed.

  7. Heat capacity and phonon mean free path in the biocarbon matrix of beech

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Wlosewicz, D.; Jezowski, A.

    2011-08-01

    The heat capacity at constant pressure C p of the biocarbon matrix prepared at a beech wood carbonization temperature of 1000°C has been measured in the temperature range 80-300 K. It has been shown that, in the temperature range 90-180 K, the heat capacity is C ˜ T 0.8 and, at T = 190-300 K, it is C p ˜ T 1.2. The phonon mean free path l( T) in the biocarbon matrix has been calculated using the obtained dependences C p ( T), our previous results on the phonon thermal conductivity of the carbon framework of this biocarbon matrix, and data available in the literature on the sound velocity in the matrix. It has been demonstrated that, in the temperature range 200-300 K, the mean value of l is ˜ 15 Å, which is close to the sizes of nanocrystallites ("carbon fragments") of ˜ 12Å, obtained earlier from X-ray diffraction data for the carbon matrix under consideration. These nanocrystallites participate in the formation of the carbon framework of the beech wood biocarbon matrix.

  8. Climate threats on growth of rear-edge European beech peripheral populations in Spain

    Science.gov (United States)

    Dorado-Liñán, I.; Akhmetzyanov, L.; Menzel, A.

    2017-12-01

    European beech ( Fagus sylvatica L.) forests in the Iberian Peninsula are a clear example of a temperate forest tree species at the rear edge of its large distribution area in Europe. The expected drier and warmer climate may alter tree growth and species distribution. Consequently, the peripheral populations will most likely be the most threatened ones. Four peripheral beech forests in the Iberian Peninsula were studied in order to assess the climate factors influencing tree growth for the last six decades. The analyses included an individual tree approach in order to detect not only the changes in the sensitivity to climate but also the potential size-mediated sensitivity to climate. Our results revealed a dominant influence of previous and current year summer on tree growth during the last six decades, although the analysis in two equally long periods unveiled changes and shifts in tree sensitivity to climate. The individual tree approach showed that those changes in tree response to climate are not size dependent in most of the cases. We observed a reduced negative effect of warmer winter temperatures at some sites and a generalized increased influence of previous year climatic conditions on current year tree growth. These results highlight the crucial role played by carryover effects and stored carbohydrates for future tree growth and species persistence.

  9. Gap Dynamics and Structure of Two Old-Growth Beech Forest Remnants in Slovenia

    Science.gov (United States)

    Rugani, Tihomir; Diaci, Jurij; Hladnik, David

    2013-01-01

    Context Due to a long history of intensive forest exploitation, few European beech (Fagus sylvatica L.) old-growth forests have been preserved in Europe. Material and Methods We studied two beech forest reserves in southern Slovenia. We examined the structural characteristics of the two forest reserves based on data from sample plots and complete inventory obtained from four previous forest management plans. To gain a better understanding of disturbance dynamics, we used aerial imagery to study the characteristics of canopy gaps over an 11-year period in the Kopa forest reserve and a 20-year period in the Gorjanci forest reserve. Results The results suggest that these forests are structurally heterogeneous over small spatial scales. Gap size analysis showed that gaps smaller than 500 m2 are the dominant driving force of stand development. The percentage of forest area in canopy gaps ranged from 3.2 to 4.5% in the Kopa forest reserve and from 9.1 to 10.6% in the Gorjanci forest reserve. These forests exhibit relatively high annual rates of coverage by newly established (0.15 and 0.25%) and closed (0.08 and 0.16%) canopy gaps. New gap formation is dependant on senescent trees located throughout the reserve. Conclusion We conclude that these stands are not even-sized, but rather unevenly structured. This is due to the fact that the disturbance regime is characterized by low intensity, small-scale disturbances. PMID:23308115

  10. Preservation of beech and spruce wood by allyl alcohol-based copolymers

    International Nuclear Information System (INIS)

    Solpan, Dilek; Gueven, Olgun

    1999-01-01

    Allyl alcohol (AA), acrylonitrile (AN), methyl methacrylate (MMA), monomers and monomer mixtures AA+AN, AA+MMA were used to conserve and consolidate Beech and Spruce. After impregnation, copolymerisation and polymerisation were accomplished by gamma irradiation. The fine structure of wood+polymer(copolymer) composites was investigated by Scanning Electron Microscopy (SEM). It was observed that copolymer obtained from AA+MMA monomer mixture showed the optimum compatibility. The compressional strength and Brinell Hardness Numbers determined for untreated and treated wood samples indicated that the mechanical strength of wood+copolymer composites was increased. It was found that the mechanical strength of the wood samples containing the AA+MMA copolymer was higher than the others. In the presence of P(AA/MMA), at highest conversion, the compressive strength perpendicular to the fibres in Beech and Spruce increased approximately 100 times. The water uptake capacity of wood+copolymer composites was observed to decrease by more than 50% relative to the original samples, and biodegradation did not take place

  11. Phytotoxic substances in soils of polluted beech forest stands; Phytotoxische Stoffe in Boeden immissionsbelasteter Buchenwaelder

    Energy Technology Data Exchange (ETDEWEB)

    Glavac, V.; Parlar, H.; Michalas, F.; Droefke, P.

    1992-12-31

    Extensive germination experiments and growth experiments were carried out under controlled laboratory conditions with garden cress (Lepidium sativum ssp. sativum). The experiments show that the germination capacity ability of the plants in soil areas under old beech trees which are influenced by the trunk runoff water is impaired considerably. The investigations with nutrient solutions permit the following conclusion: The absence or occurrence of germinating plant species in the tree foot area is not influenced by the minerals alone but above all by organic compounds. In this investigation, the growth-inhibiting effect of several phenolic acids occurring in beech forests is recognized. (orig.) [Deutsch] Die umfangreichen Keim- und Wachstumsversuche mit der Gartenkresse (Lepidium sativum ssp.sativum), die unter kontrollierten Laborbedingungen durchgefuehrt wurden, zeigen, dass die Keimfaehigkeit der Pflanzen in den vom Stammablaufwasser beeinflussten Bodenbereichen der Altbuchen deutlich gehemmt wird. Die Untersuchungen mit Naehrloesungen lassen die Schlussfolgerung zu, dass nicht die Mineralstoffe allein, sondern vor allem organische Verbindungen das Fehlen oder Vorkommen aufkeimender Pflanzenarten im Baumflussbereich weitgehend bedingen. In dieser Untersuchung wird die wachstumshemmende Wirkung von mehreren im Oekosystem Buchenwald vorkommenden phenolischen Saeuren nachgewiesen. (orig.)

  12. Belowground effects of enhanced tropospheric ozone and drought in a beech/spruce forest (Fagus sylvatica L./Picea abies [L.] Karst)

    International Nuclear Information System (INIS)

    Nikolova, Petia S.; Andersen, Christian P.; Blaschke, Helmut; Matyssek, Rainer; Haeberle, Karl-Heinz

    2010-01-01

    The effects of experimentally elevated O 3 on soil respiration rates, standing fine-root biomass, fine-root production and δ 13 C signature of newly produced fine roots were investigated in an adult European beech/Norway spruce forest in Germany during two subsequent years with contrasting rainfall patterns. During humid 2002, soil respiration rate was enhanced under elevated O 3 under beech and spruce, and was related to O 3 -stimulated fine-root production only in beech. During dry 2003, the stimulating effect of O 3 on soil respiration rate vanished under spruce, which was correlated with decreased fine-root production in spruce under drought, irrespective of the O 3 regime. δ 13 C signature of newly formed fine-roots was consistent with the differing g s of beech and spruce, and indicated stomatal limitation by O 3 in beech and by drought in spruce. Our study showed that drought can override the stimulating O 3 effects on fine-root dynamics and soil respiration in mature beech and spruce forests. - Drought has the capacity to override the stimulating ozone effect on soil respiration in adult European beech/Norway spruce forest.

  13. Mechanical properties and chemical composition of beech wood exposed for 30 and 120 days to white-rot fungi

    Science.gov (United States)

    Ehsan Bari; Hamid Reza Taghiyari; Behbood Mohebby; Carol A. Clausen; Olaf Schmidt; Mohammad Ali Tajick Ghanbary; Mohammad Javad Vaseghi

    2015-01-01

    The effects of exposing specimens of Oriental beech [Fagus sylvatica subsp. orientalis (Lipsky) Greuter and Burdet] to the white-rot fungi Pleurotus ostreatus (Jacq.: Fr.) Kummer and Trametes versicolor (L.: Fr.) Pilát strain 325 have been studied concerning the mechanical properties and...

  14. 77 FR 31642 - Hawker Beech Craft Defense Company, LLC, Also Known As Hawker Beechcraft Corporation, Also Known...

    Science.gov (United States)

    2012-05-29

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-74,901] Hawker Beech Craft Defense Company, LLC, Also Known As Hawker Beechcraft Corporation, Also Known As Hawker Beechcraft International SVC, Also Known As Rapid Surplus Parts, Also Known As Hawker Beechcraft Svcs, Also Known As Travel...

  15. Crown plasticity and neighborhood interactions of European beech (Fagus sylvatica L.) in an old-growth forest

    NARCIS (Netherlands)

    Schröter, M.; Härdtle, W.; Oheimb, von G.

    2012-01-01

    Competition for canopy space is a process of major importance in forest dynamics. Although virgin and old-growth European beech (Fagus sylvatica L.) forests in Europe have been studied for many years, there are to date no studies of individual-tree crown plasticity and the way this is influenced by

  16. Removal of non benzidine direct red dye from aqueous solution by using natural sorbents: Beech and silver fir

    Czech Academy of Sciences Publication Activity Database

    Muntean, S.G.; Todea, A.; Bakardjieva, Snejana; Bologa, C.

    2017-01-01

    Roč. 66, MAR (2017), s. 235-250 ISSN 1944-3994 Institutional support: RVO:61388980 Keywords : Adsorption * Beech * Direct red * Kinetics * Silver fir Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 1.631, year: 2016

  17. The formation of a ligno-suberised layer and necrophylactic periderm in beech bark (Fagus sylvatica L.)

    Science.gov (United States)

    Primoz Oven; Niko Torelli; Walter C. Shortle; Martin Zupancic

    1999-01-01

    Beech (Fagus sylvatica L.) bark was wounded in early April of 1993 and tissue changes followed on days 7, 14, 21, 28, 35, 42, 49, 56, 84, 112, and 140. In 7 days, tissue at the wound surface became necrotic and discoloured. In 14 days the walls of the parenchyma cells immediately underneath the necrotic tissue became thickened and after 21 days...

  18. Supercritical fluid regeneration of adsorbents

    Science.gov (United States)

    Defilippi, R. P.; Robey, R. J.

    1983-05-01

    The results of a program to perform studies supercritical (fluid) carbon dioxide (SCF CO2) regeneration of adsorbents, using samples of industrial wastewaters from manufacturing pesticides and synthetic solution, and to estimate the economics of the specific wastewater treatment regenerations, based on test data are given. Processing costs for regenerating granular activated carbon GAC) for treating industrial wastewaters depend on stream properties and regeneration throughput.

  19. An active magnetic regenerator device

    DEFF Research Database (Denmark)

    2015-01-01

    A rotating active magnetic regenerator (AMR) device comprising two or more regenerator beds, a magnet arrangement and a valve arrangement. The valve arrangement comprises a plurality of valve elements arranged substantially immovably with respect to the regenerator beds along a rotational direction...

  20. Infection and Pulp Regeneration

    Directory of Open Access Journals (Sweden)

    Sahng G. Kim

    2016-03-01

    Full Text Available The regeneration of the pulp-dentin complex has been a great challenge to both scientists and clinicians. Previous work has shown that the presence of prior infection may influence the characteristics of tissues formed in the root canal space after regenerative endodontic treatment. The formation of ectopic tissues such as periodontal ligament, bone, and cementum has been observed in the root canal space of immature necrotic teeth with apical periodontitis, while the regeneration of dentin and pulp has been identified in previously non-infected teeth. The current regenerative endodontic therapy utilizes disinfection protocols, which heavily rely on chemical irrigation using conventional disinfectants. From a microbiological point of view, the current protocols may not allow a sufficiently clean root canal microenvironment, which is critical for dentin and pulp regeneration. In this article, the significance of root canal disinfection in regenerating the pulp-dentin complex, the limitations of the current regenerative endodontic disinfection protocols, and advanced disinfection techniques designed to reduce the microorganisms and biofilms in chronic infection are discussed.

  1. Plant regeneration through indirect organogenesis of chestnut ...

    African Journals Online (AJOL)

    Mehrcedeh

    2013-12-18

    Dec 18, 2013 ... Druce-A multiple desert tree. Researcher 1:28-32. Kvaalen H, Gram Daehlen O, Tove Rognstad A, Grǿnstad B,. Egertsdotter U (2005). Somatic embryogenesis for plant production of. Abies lasiocarpa. Can. J. For. Res. 35:1053-1060. Liu CZ, Murch SJ, Demerdash MEL, Saxena PK (2003). Regeneration.

  2. Oak Regeneration Guidelines for the Central Appalachians

    Science.gov (United States)

    Kim C. Steiner; James C. Finley; Peter J. Gould; Songlin Fei; Marc McDill

    2008-01-01

    This article presents the first explicit guidelines for regenerating oaks in the central Appalachians. The objectives of this paper are (1) to describe the research foundation on which the guidelines are based and (2) to provide users with the instructions, data collection forms, supplementary tables, and decision charts needed to apply the guidelines in the field. The...

  3. Stimulating endogenous cardiac regeneration

    Directory of Open Access Journals (Sweden)

    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  4. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand's southern beech treelines.

    Science.gov (United States)

    Case, Bradley S; Buckley, Hannah L

    2015-01-01

    Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m) meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential of such an approach

  5. Increased carbon sequestration in a Danish beech forest during 1996-2016: Observations and hypotheses.

    Science.gov (United States)

    Pilegaard, Kim; Ibrom, Andreas

    2017-04-01

    A study of the net exchange of CO2 (NEE) between the atmosphere and a beech forest near Sorø, Denmark, during 14 years (1996-2009) showed that the beech forest acted as an increasing sink of CO2 [1]. A significant increase in gross primary production (GPP) and a smaller and not significant increase in ecosystem respiration (RE) were also found. Thus, the increased NEE was mainly attributed to an increase in GPP. The length of the carbon uptake period (CUP) significantly increased, whereas there was a no increase in the leafed period (LP). This means that the leaves stayed active longer. The increase in the carbon uptake period explained about half of the increasing NEE. The remaining increase was believed to be due to an observed increased uptake capacity of the canopy and increased annual radiation efficiency[2]. The causes for this were hypothesized to be a combination of increase in atmospheric CO2 concentration, higher summer precipitation, and increased availability of N. A higher nitrogen content in the leaves was observed towards the end of the observation period. An updated analysis of the flux data, now including the years 1996-2016, confirms the increasing trend in carbon sequestration of the forest, an increasingly longer growing season, and a significant correlation of NEE and CUP, however, similarly to the first study, the increase in CUP only explains about half of the total increase. Here we investigate three hypotheses for the remaining reasons for the increase: H1: increased canopy nitrogen content H2: carbon dioxide fertilisation H3: increased water availability due to changing precipitation patterns. We describe the multiannual development of canopy photosynthesis capacity with regression analysis and perform sensitivity studies with the canopy model MAESTRA [3] to investigate the above hypotheses. The results will be presented, critically discussed and interpreted with respect to general effects of global climate change and site specific, local

  6. Testing the applicability of BIOME-BGC to simulate beech gross primary production in Europe using a new continental weather dataset

    DEFF Research Database (Denmark)

    Chiesi, Marta; Chirici, Gherardo; Marchetti, Marco

    2016-01-01

    A daily 1-km Pan-European weather dataset can drive the BIOME-BGC model for the estimation of current and future beech gross primary production (GPP). Annual beech GPP is affected primarily by spring temperature and more irregularly by summer water stress.The spread of beech forests in Europe...... forest ecosystems having different climatic conditions where the eddy covariance technique is used to measure water and carbon fluxes. The experiment is in three main steps. First, the accuracy of BIOME-BGC GPP simulations is assessed through comparison with flux observations. Second, the influence...... of two major meteorological drivers (spring minimum temperature and growing season dryness) on observed and simulated inter-annual GPP variations is analysed. Lastly, the impacts of two climate change scenarios on beech GPP are evaluated through statistical analyses of the ground data and model...

  7. Capacity issues in local communities for integral urban regeneration

    Directory of Open Access Journals (Sweden)

    Mrđenović Tatjana

    2013-01-01

    Full Text Available The subject of the research in wider sense is organizational-communication capacity of local communities in Serbia in the frame of sustainable development. Along with this, the paper will explore potentialities of Faludi's model of multiplanning agencies as well as Healey's collaborative theory for better efficiency and effectiveness of planning in the process of urban regeneration. Specifically the paper will research relation between organizational structure of local communities in Serbia and their potentialities to provide adequate communication towards integral information for urban regeneration. Research is framed with a problem of efficiency and effectiveness in creating urban regeneration policies, strategies, designs, and technical solutions. The problem will be focused to Serbian context; characterized with inadequate, transitional, system of governance that is moving from centralistic towards decentralist model. This will be further explored through level and type of participation in the process of urban regeneration. The hypothesis of the research explores the nature of the relation between number and types of communication channels, provided by organizational structure of local communities that should enable effectiveness and efficiency of urban regeneration. In other words the hypothesis is: number and types of communication channels (variable A influences the effectiveness and efficiency of urban planning for sustainable urban regeneration (variable B. The aims of the paper are identification of the regulations between the variables. Expected result is establishing the model for measuring the capacity of local communities for integral urban regeneration.

  8. Perkembangan Terkini Membran Guided Tissue Regeneration/Guided Bone Regeneration sebagai Terapi Regenerasi Jaringan Periodontal

    Directory of Open Access Journals (Sweden)

    Cindy Cahaya

    2015-06-01

    kombinasi prosedur-prosedur di atas, termasuk prosedur bedah restoratif yang berhubungan dengan rehabilitasi oral dengan penempatan dental implan. Pada tingkat selular, regenerasi periodontal adalah proses kompleks yang membutuhkan proliferasi yang terorganisasi, differensiasi dan pengembangan berbagai tipe sel untuk membentuk perlekatan periodontal. Rasionalisasi penggunaan guided tissue regeneration sebagai membran pembatas adalah menahan epitel dan gingiva jaringan pendukung, sebagai barrier membrane mempertahankan ruang dan gigi serta menstabilkan bekuan darah. Pada makalah ini akan dibahas sekilas mengenai 1. Proses penyembuhan terapi periodontal meliputi regenerasi, repair ataupun pembentukan perlekatan baru. 2. Periodontal spesific tissue engineering. 3. Berbagai jenis membran/guided tissue regeneration yang beredar di pasaran dengan keuntungan dan kerugian sekaligus karakteristik masing-masing membran. 4. Perkembangan membran terbaru sebagai terapi regenerasi penyakit periodontal. Tujuan penulisan untuk memberi gambaran masa depan mengenai terapi regenerasi yang menjanjikan sebagai perkembangan terapi penyakit periodontal.   Latest Development of Guided Tissue Regeneration and Guided Bone Regeneration Membrane as Regenerative Therapy on Periodontal Tissue. Periodontitis is a patological state which influences the integrity of periodontal system that could lead to the destruction of the periodontal tissue and end up with tooth loss. Currently, there are so many researches and efforts to regenerate periodontal tissue, not only to stop the process of the disease but also to reconstruct the periodontal tissue. Periodontal regenerative therapy aims at directing the growth of new bone, cementum and periodontal ligament on the affected teeth. Regenerative procedures consist of soft tissue graft, bone graft, roots biomodification, guided tissue regeneration and combination of the procedures, including restorative surgical procedure that is

  9. Unique Aspects of Cryptochrome in Chronobiology and Metabolism, Pancreatic β-Cell Dysfunction, and Regeneration: Research into Cysteine414-Alanine Mutant CRY1

    Directory of Open Access Journals (Sweden)

    Satoshi Okano

    2016-01-01

    Full Text Available Cryptochrome proteins (CRYs, which can bind noncovalently to cofactor (chromophore flavin adenine dinucleotide (FAD, occur widely among organisms. CRYs play indispensable roles in the generation of circadian rhythm in mammals. Transgenic mice (Tg mice, ubiquitously expressing mouse CRY1 having a mutation in which cysteine414 (the zinc-binding site of CRY1 being replaced with alanine, display unique phenotypes in their circadian rhythms. Moreover, male Tg mice exhibit symptoms of diabetes characterized by beta-cell dysfunction, resembling human maturity onset diabetes of the young (MODY. The lowered proliferation of β-cells is a primary cause of age-dependent β-cell loss. Furthermore, unusually enlarged duct-like structures developed prominently in the Tg mice pancreases. The duct-like structures contained insulin-positive cells, suggesting neogenesis of β-cells in the Tg mice. This review, based mainly on the author’s investigation of the unique features of Tg mice, presents reported results and recent findings related to molecular processes associated with mammalian cryptochromes, especially their involvement in the regulation of metabolism. New information is described with emphasis on the aspects of islet architecture, pancreatic β-cell dysfunction, and regeneration.

  10. Biological regeneration of humic acid-loaded partially exhausted activated carbon (down flow system)

    International Nuclear Information System (INIS)

    Durrani, M.A.Q.J.; Martin, R.J.; Khaliq, F.

    1995-01-01

    This paper represents the report on the biological regeneration of partially exhausted (down flow) activated carbon following the experimental studies carried out at the university of Birmingham, UK. The Research investigated the extent of bio regeneration of humic acid of concentration 100 mg/l. Bio regeneration in the partial exhaustion system (down flow) was evaluated in terms of substrate removal. Bacterial counts in the effluents of regenerated GAC columns were significantly more than those of fresh carbon effluents. The regeneration performance of the bio regeneration, partially exhausted (with humic acid) carbon increased during initial cycles, later on, it deteriorated significantly with each successive regeneration cycle. Microbial fouling of the carbon, especially at the bottom of the carbon bed was found to produce a substantial deterioration of the bio regeneration performance. (author)

  11. Black carbon surface oxidation and organic composition of beech-wood soot aerosols

    Directory of Open Access Journals (Sweden)

    J. C. Corbin

    2015-10-01

    oxygenated carbonaceous ions (CO1-2+, potassium (K+, and water (H2O+ and related fragments. The C4+ : C3+ ratio, but not the C1+ : C3+ ratio, was consistent with the BC-structure trends of Corbin et al. (2015c. The CO1-2+ signals likely originated from BC surface groups: upon aging, both CO+ and CO2+ increased relative to C1-3+ while CO2+ simultaneously increased relative to CO+. Factor analysis (positive matrix factorization of SP-AMS and AMS data, using a modified error model to address peak-integration uncertainties, indicated that the surface composition of the BC was approximately constant across all stages of combustion for both fresh and aged samples. These results represent the first time-resolved measurements of in situ BC surface aging and suggest that the surface of beech-wood BC may be modelled as a single chemical species.

  12. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    Directory of Open Access Journals (Sweden)

    Y. van Meeningen

    2017-09-01

    Full Text Available Light is an important environmental factor controlling biogenic volatile organic compound (BVOC emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur, European beech (Fagus sylvatica and two provenances of Norway spruce (Picea abies in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m−2 s−1, whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the

  13. Transfer Analysis of Provenance Trials Reveals Macroclimatic Adaptedness of European Beech (Fagus sylvatica L.

    Directory of Open Access Journals (Sweden)

    RASZTOVITS, Ervin

    2009-01-01

    Full Text Available The aim of the study was to analyse provenance tests of beech situated close to theSoutheastern-continental limits of the species, in order to develop a response model of adaptation andplasticity of populations on evolutionary-ecological basis, following sudden climatic changes as aresult of transplanting. Modelling of juvenile height was performed with the help of ecodistancevariables. The concept of transfer analysis and ecodistance is based on the hypothesis that phenotypicresponse to macroclimatic changes depends on the inherited adaptive potential of the population andon the magnitude and direction of experienced environmental change. In common garden experiments,the transfer to the planting site is interpreted as simulation of environmental change. The applicationof ecodistance of transfer for evaluating common garden experiments provides much neededquantitative information about response of tree populations to predicted climatic changes.The analysis of three field experiments of European beech in SE Europe invalidate earlier doubtsabout the existence of macroclimatic adaptation patterns in juvenile growth and justify restrictions ofuse of reproductive material on the basis of evolutionary ecology. The presented model illustrates thatresponse to climatic change is regionally divergent, depending on testing conditions and on hereditarytraits. In particular, climatic warming in the central-northern part of the range may lead to productionincrease. However, under the stressful and uncertain conditions at the lower (xeric limit of thespecies, growth depression and vitality loss are predicted. The deviating behaviour of higher elevationprovenances support their separate treatment.The results may be utilised in climate change adaptation and mitigation policy in forestry andnature conservation, to revise rules for use of reproductive material and also for validatingevolutionary and ecological hypotheses related to climate change effects.

  14. Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

    Science.gov (United States)

    van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka; Holst, Thomas

    2017-09-01

    Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 µmol m-2 s-1), whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds α-pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds α-pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or

  15. Forty-two years of change in an old-growth and second-growth beech-maple forest of north central Ohio

    Science.gov (United States)

    Natalie R. Pinheiro; P. Charles Goebel; David M. Hix

    2008-01-01

    Using data collected in 1964 and 2006, we examined changes in the composition and structure of a second-growth and old-growth beech-maple forest of Crall Woods, located in Ashland County of north central Ohio. Over the 42 years, the old-growth forest (estimated to be at least 250 years old) experienced a significant shift in species composition as American beech,...

  16. Major Changes in Growth Rate and Growth Variability of Beech (Fagus sylvatica L.) Related to Soil Alteration and Climate Change in Belgium

    OpenAIRE

    Latte, Nicolas; Perin, Jérôme; Kint, Vincent; Lebourgeois, François; Claessens, Hugues

    2016-01-01

    Global change-particularly climate change, forest management, and atmospheric deposition-has significantly altered forest growing conditions in Europe. The influences of these changes on beech growth (Fagus sylvatica L.) were investigated for the past 80 years in Belgium, using non-linear mixed effects models on ring-width chronologies of 149 mature and dominant beech trees (87-186 years old). The effects of the developmental stage (i.e., increasing tree size) were filtered out in order to fo...

  17. Regeneration of plantlets from unpollinated ovary cultures of ...

    African Journals Online (AJOL)

    Tsega

    2013-09-25

    Sep 25, 2013 ... 3Ethiopian Institute of Agricultural Research (EIAR): Holetta ... cultured unpollinated ovaries, 1,100 embryonic tissues (7.6 %) and 75 regenerants were obtained. The ... viral diseases, insect pests and increasing human popu-.

  18. Competition modifies effects of enhanced ozone/carbon dioxide concentrations on carbohydrate and biomass accumulation in juvenile Norway spruces and European beech

    International Nuclear Information System (INIS)

    Liu, X.; Rennenberg, H.; Kozovits, A. R.; Grams, T. E.; Blaschke, H.; Matyssek, R.

    2004-01-01

    Potential interactions of carbon dioxide and ozone on carbohydrate concentrations and contents were studied in Norway spruce and European beech saplings to test the hypotheses that (1) prolonged exposure to elevated carbon dioxide does not compensate for the limiting effects of ozone on the accumulation of sugars and starches, or biomass partitioning to the root; and (2) growth of mixed-species planting will repress plant responses to elevated ozone and carbon dioxide. Norway spruce and European beech saplings were acclimated for one year to ambient and elevated carbon dioxide, followed by exposure to factorial combinations of ambient and elevated ozone and carbon dioxide during the next two years. In spruce trees, sugar and starch content was greater in saplings exposed to elevated carbon dioxide; in beech, the response was the opposite. The overall conclusion was that the results did not support Hypothesis One, because the adverse effects were counteracted by elevated carbon dioxide. Regarding Hypothesis Two, it was found to be supportive for beech but not for spruce. In beech, the reduction of sugars and starch by elevated ozone and stimulation by elevated carbon dioxide were repressed by competitive interaction with spruce, whereas in spruce saplings elevated concentrations of carbon dioxide resulted in higher concentrations of sugar and starch, but only in leaves and coarse roots and only when grown in combination with beech. Elevated ozone in spruce saplings produced no significant effect on sugar or starch content either in intra- or interspecific competition. 57 refs., 1 tab., 5 figs

  19. Competition modifies effects of enhanced ozone/carbon dioxide concentrations on carbohydrate and biomass accumulation in juvenile Norway spruces and European beech

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.; Rennenberg, H. [University of Freiburg, Inst. of Forest Botany and Tree Physiology, Freiburg (Germany); Kozovits, A. R.; Grams, T. E.; Blaschke, H.; Matyssek, R. [Technische Universitat Munchen, Dept. of Ecology and Ecophysiology of Plants, Freising (Germany)

    2004-09-01

    Potential interactions of carbon dioxide and ozone on carbohydrate concentrations and contents were studied in Norway spruce and European beech saplings to test the hypotheses that (1) prolonged exposure to elevated carbon dioxide does not compensate for the limiting effects of ozone on the accumulation of sugars and starches, or biomass partitioning to the root; and (2) growth of mixed-species planting will repress plant responses to elevated ozone and carbon dioxide. Norway spruce and European beech saplings were acclimated for one year to ambient and elevated carbon dioxide, followed by exposure to factorial combinations of ambient and elevated ozone and carbon dioxide during the next two years. In spruce trees, sugar and starch content was greater in saplings exposed to elevated carbon dioxide; in beech, the response was the opposite. The overall conclusion was that the results did not support Hypothesis One, because the adverse effects were counteracted by elevated carbon dioxide. Regarding Hypothesis Two, it was found to be supportive for beech but not for spruce. In beech, the reduction of sugars and starch by elevated ozone and stimulation by elevated carbon dioxide were repressed by competitive interaction with spruce, whereas in spruce saplings elevated concentrations of carbon dioxide resulted in higher concentrations of sugar and starch, but only in leaves and coarse roots and only when grown in combination with beech. Elevated ozone in spruce saplings produced no significant effect on sugar or starch content either in intra- or interspecific competition. 57 refs., 1 tab., 5 figs.

  20. Use of sap flow measurements to validate stomatal functions for mature beech (Fagus sylvatica) in view of ozone uptake calculations

    International Nuclear Information System (INIS)

    Braun, Sabine; Schindler, Christian; Leuzinger, Sebastian

    2010-01-01

    For a quantitative estimate of the ozone effect on vegetation reliable models for ozone uptake through the stomata are needed. Because of the analogy of ozone uptake and transpiration it is possible to utilize measurements of water loss such as sap flow for quantification of ozone uptake. This technique was applied in three beech (Fagus sylvatica) stands in Switzerland. A canopy conductance was calculated from sap flow velocity and normalized to values between 0 and 1. It represents mainly stomatal conductance as the boundary layer resistance in forests is usually small. Based on this relative conductance, stomatal functions to describe the dependence on light, temperature, vapour pressure deficit and soil moisture were derived using multivariate nonlinear regression. These functions were validated by comparison with conductance values directly estimated from sap flow. The results corroborate the current flux parameterization for beech used in the DO 3 SE model. - A method was developed to derive stomatal functions and ozone uptake calculation from sap flow.

  1. The effects of habitat degradation on metacommunity structure of wood-inhabiting fungi in European beech forests

    DEFF Research Database (Denmark)

    Halme, Panu; Ódor, Péter; Christensen, Morten

    2013-01-01

    Intensive forest management creates habitat degradation by reducing the variation of forest stands in general, and by removing old trees and dead wood in particular. Non-intervention forest reserves are commonly believed to be the most efficient tool to counteract the negative effects...... with different management histories. For this purpose, we used a large data set of wood-inhabiting fungi collected from dead beech trees in European beech-dominated forest reserves. The structure of fungal assemblages showed high beta diversity, while nestedness and similarity was low. During the decomposition...... extirpated specialized species from the local species pools in managed sites, and resulted in more homogeneous communities in managed sites. It is alarming that community structure is affected the most in the latest decay stages where the decay process turns the dead wood into litter, and which is thus...

  2. Generating private co-investments in area-based urban regeneration: Lessons from Denmark

    DEFF Research Database (Denmark)

    Jensen, Jesper Ole; Larsen, Jacob Norvig; Storgaard, Kresten

    a factor 5 times higher than the public investments in the areas, in terms of urban regeneration subsidies. Private investments, however, might cover different property investment strategies: ‘Passive management’, ‘active management’ and ‘development’. We suggest that for the urban regeneration areas......In recent years, public-private collaboration as well as private co-investments has been intensely promoted in Danish area-based urban regeneration policy and programmes. The paper will discuss to which extent these ambitions have been full-filled, and what has actually attracted private...... investments to the urban regeneration areas. The paper is based on evaluations of the Danish area-based regeneration programmes, as well as research on private investments in selected urban regeneration areas. Our research shows that area-based urban regeneration in average generates private investments...

  3. Synthetic Phage for Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    So Young Yoo

    2014-01-01

    Full Text Available Controlling structural organization and signaling motif display is of great importance to design the functional tissue regenerating materials. Synthetic phage, genetically engineered M13 bacteriophage has been recently introduced as novel tissue regeneration materials to display a high density of cell-signaling peptides on their major coat proteins for tissue regeneration purposes. Structural advantages of their long-rod shape and monodispersity can be taken together to construct nanofibrous scaffolds which support cell proliferation and differentiation as well as direct orientation of their growth in two or three dimensions. This review demonstrated how functional synthetic phage is designed and subsequently utilized for tissue regeneration that offers potential cell therapy.

  4. Understanding Urban Regeneration in Turkey

    Science.gov (United States)

    Candas, E.; Flacke, J.; Yomralioglu, T.

    2016-06-01

    In Turkey, rapid population growth, informal settlements, and buildings and infrastructures vulnerable to natural hazards are seen as the most important problems of cities. Particularly disaster risk cannot be disregarded, as large parts of various cities are facing risks from earthquakes, floods and landslides and have experienced loss of lives in the recent past. Urban regeneration is an important planning tool implemented by local and central governments in order to reduce to disaster risk and to design livable environments for the citizens. The Law on the Regeneration of Areas under Disaster Risk, commonly known as the Urban Regeneration Law, was enacted in 2012 (Law No.6306, May 2012). The regulation on Implementation of Law No. 6306 explains the fundamental steps of the urban regeneration process. The relevant institutions furnished with various authorities such as expropriation, confiscation and changing the type and place of your property which makes urban regeneration projects very important in terms of property rights. Therefore, urban regeneration projects have to be transparent, comprehensible and acceptable for all actors in the projects. In order to understand the urban regeneration process, the legislation and projects of different municipalities in Istanbul have been analyzed. While some steps of it are spatial data demanding, others relate to land values. In this paper an overview of the urban regeneration history and activities in Turkey is given. Fundamental steps of the urban regeneration process are defined, and particularly spatial-data demanding steps are identified.

  5. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    Energy Technology Data Exchange (ETDEWEB)

    Olbrich, Maren, E-mail: maren.olbrich@helmholtz-muenchen.d [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Gerstner, Elke; Bahnweg, Guenther [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Haeberle, Karl-Heinz; Matyssek, Rainer [Technische Universitaet Muenchen, Ecophysiology of Plants, Am Hochanger 13, 85354 Freising (Germany); Welzl, Gerhard [Institute of Developmental Genetics, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Heller, Werner; Ernst, Dieter [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany)

    2010-04-15

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  6. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    International Nuclear Information System (INIS)

    Olbrich, Maren; Gerstner, Elke; Bahnweg, Guenther; Haeberle, Karl-Heinz; Matyssek, Rainer; Welzl, Gerhard; Heller, Werner; Ernst, Dieter

    2010-01-01

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  7. Influence of litter diversity on dissolved organic matter release and soil carbon formation in a mixed beech forest.

    Science.gov (United States)

    Scheibe, Andrea; Gleixner, Gerd

    2014-01-01

    We investigated the effect of leaf litter on below ground carbon export and soil carbon formation in order to understand how litter diversity affects carbon cycling in forest ecosystems. 13C labeled and unlabeled leaf litter of beech (Fagus sylvatica) and ash (Fraxinus excelsior), characterized by low and high decomposability, were used in a litter exchange experiment in the Hainich National Park (Thuringia, Germany). Litter was added in pure and mixed treatments with either beech or ash labeled with 13C. We collected soil water in 5 cm mineral soil depth below each treatment biweekly and determined dissolved organic carbon (DOC), δ13C values and anion contents. In addition, we measured carbon concentrations and δ13C values in the organic and mineral soil (collected in 1 cm increments) up to 5 cm soil depth at the end of the experiment. Litter-derived C contributes less than 1% to dissolved organic matter (DOM) collected in 5 cm mineral soil depth. Better decomposable ash litter released significantly more (0.50±0.17%) litter carbon than beech litter (0.17±0.07%). All soil layers held in total around 30% of litter-derived carbon, indicating the large retention potential of litter-derived C in the top soil. Interestingly, in mixed (ash and beech litter) treatments we did not find a higher contribution of better decomposable ash-derived carbon in DOM, O horizon or mineral soil. This suggest that the known selective decomposition of better decomposable litter by soil fauna has no or only minor effects on the release and formation of litter-derived DOM and soil organic matter. Overall our experiment showed that 1) litter-derived carbon is of low importance for dissolved organic carbon release and 2) litter of higher decomposability is faster decomposed, but litter diversity does not influence the carbon flow.

  8. Pancreatic islet regeneration: Therapeutic potential, unknowns and controversy

    Directory of Open Access Journals (Sweden)

    Ingrid L. Cockburn

    2015-07-01

    Full Text Available Glucose homeostasis in mammals is primarily maintained by the insulin-secreting β-cells contained within pancreas-resident islets of Langerhans. Gross disruption of this glucose regulation as a result of pancreatic dysfunction frequently results in diabetes, which is currently a major health concern in South Africa, as well as globally. For many years, researchers have realised that the pancreas, and specifically the islets of Langerhans, have a regenerative capacity, as islet mass has frequently been shown to increase following induced pancreatic injury. Given that gross β-cell loss contributes significantly to the pathogenesis of both type 1 and type 2 diabetes, endogenous pancreatic islet regeneration has been investigated extensively as a potential β-cell replacement therapy for diabetes. From the extensive research conducted on pancreatic regeneration, opposing findings and opinions have arisen as to how, and more recently even if, pancreatic regeneration occurs following induced injury. In this review, we outline and discuss the three primary mechanisms by which pancreatic regeneration is proposed to occur: neogenesis, β-cell replication and transdifferentiation. We further explain some of the advanced techniques used in pancreatic regeneration research, and conclude that despite the technologically advanced research tools available to researchers today, the mechanisms governing pancreatic regeneration may remain elusive until more powerful techniques are developed to allow for real-time, live-cell assessment of morphology and gene expression within the pancreas.

  9. Advancing research in regeneration and repair of the motor circuitry: non-human primate models and imaging scales as the missing links for successfully translating injectable therapeutics to the clinic.

    Science.gov (United States)

    Tsintou, Magdalini; Dalamagkas, Kyriakos; Makris, Nikos

    2016-01-01

    Regeneration and repair is the ultimate goal of therapeutics in trauma of the central nervous system (CNS). Stroke and spinal cord injury (SCI) are two highly prevalent CNS disorders that remain incurable, despite numerous research studies and the clinical need for effective treatments. Neural engineering is a diverse biomedical field, that addresses these diseases using new approaches. Research in the field involves principally rodent models and biologically active, biodegradable hydrogels. Promising results have been reported in preclinical studies of CNS repair, demonstrating the great potential for the development of new treatments for the brain, spinal cord and peripheral nerve injury. Several obstacles stand in the way of clinical translation of neuroregeneration research. There seems to be a key gap in the translation of research from rodent models to human applications, namely non-human primate models, which constitute a critical bridging step. Applying injectable therapeutics and multimodal neuroimaging in stroke lesions using experimental rhesus monkey models is an avenue that a few research groups have begun to embark on. Understanding and assessing the changes that the injured brain or spinal cord undergoes after an intervention with biodegradable hydrogels in non-human primates seem to represent critical preclinical research steps. Existing innovative models in non-human primates allow us to evaluate the potential of neural engineering and injectable hydrogels. The results of these preliminary studies will pave the way for translating this research into much needed clinical therapeutic approaches. Cutting edge imaging technology using Connectome scanners represents a tremendous advancement, enabling the in vivo, detailed, high-resolution evaluation of these therapeutic interventions in experimental animals. Most importantly, they also allow quantifiable and clinically meaningful correlations with humans, increasing the translatability of these

  10. Attraction and antennal response of the common wasp, Vespula vulgaris (L.), to selected synthetic chemicals in New Zealand beech forests.

    Science.gov (United States)

    El-Sayed, Ashraf M; Manning, Lee-Anne; Unelius, C Rikard; Park, Kye Chung; Stringer, Lloyd D; White, Nicola; Bunn, Barry; Twidle, Andrew; Suckling, David M

    2009-09-01

    The common wasp, Vespula vulgaris (L.), and the German wasp, Vespula germanica (F.), are significant problems in New Zealand beech forests (Nothofagus spp.), adversely affecting native birds and invertebrate biodiversity. This work was undertaken to develop synthetic attractants for these species to enable more efficient monitoring and management. Seven known wasp attractants (acetic acid, butyl butyrate, isobutanol, heptyl butyrate, octyl butyrate and 2,4-hexadienyl butyrate) were field tested, and only heptyl butyrate and octyl butyrate attracted significantly higher numbers of wasps than a non-baited trap. Accordingly, a series of straight-chain esters from methyl to decyl butyrate were prepared and field tested for attraction of social wasps. Peak biological activity occurred with hexyl butyrate, heptyl butyrate, octyl butyrate and nonyl butyrate. Polyethylene bags emitting approximately 18.4-22.6 mg day(-1) of heptyl butyrate were more attractive than polyethylene bags emitting approximately 14.7-16.8 mg day(-1) of heptyl butyrate in the field. Electroantennogram (EAG) studies indicated that queens and workers of V. vulgaris had olfactory receptor neurons responding to various aliphatic butyrates. These results are the first to be reported on the EAG response and the attraction of social wasps to synthetic chemicals in New Zealand beech forests and will enable monitoring of social wasp activity in beech forests. Copyright 2009 Society of Chemical Industry.

  11. Structure, electrical resistivity, and thermal conductivity of beech wood biocarbon produced at carbonization temperatures below 1000°C

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Kartenko, N. F.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Jezowski, A.; Muha, J.; Vera, M. C.

    2011-11-01

    This paper reports on measurements of the thermal conductivity κ and the electrical resistivity ρ in the temperature range 5-300 K, and, at 300 K, on X-ray diffraction studies of high-porosity (with a channel pore volume fraction of ˜47 vol %) of the beech wood biocarbon prepared by pyrolysis (carbonization) of tree wood in an argon flow at the carbonization temperature T carb = 800°C. It has been shown that the biocarbon template of the samples studied represents essentially a nanocomposite made up of amorphous carbon and nanocrystallites—"graphite fragments" and graphene layers. The sizes of the nanocrystallites forming these nanocomposites have been determined. The dependences ρ( T) and κ( T) have been measured for the samples cut along and perpendicular to the tree growth direction, thus permitting determination of the magnitude of the anisotropy of these parameters. The dependences ρ( T) and κ( T), which have been obtained for beech biocarbon samples prepared at T carb = 800°C, are compared with the data amassed by us earlier for samples fabricated at T carb = 1000 and 2400°C. The magnitude and temperature dependence of the phonon thermal conductivity of the nanocomposite making up the beech biocarbon template at T carb = 800°C have been found.

  12. Microbiological soil regeneration

    International Nuclear Information System (INIS)

    Behrens, D.; Wiesner, J.

    1992-01-01

    The Interdiciplinary Task Force ''Environmental Biotechnology - Soil'' of DECHEMA aims to pool the knowledge potential of the Dechema study committees on environmental biotechnology and soil protection with a view to the advancement of microbiological soil decontamination techniques. This conference volume on the 9th expert meeting of Dechema on environmental protection subjects entitled ''Microbiological Soil Regeneration'', held on February 27th and 28th, 1991, and the subsequent compilation of results give an intermediate account of the ongoing work of the Dechema Task Force. (orig.) [de

  13. Sampling forest regeneration across northern U.S. forests: filling a void in regeneration model input

    Science.gov (United States)

    William H. McWilliams; Charles D. Canham; Randall S. Morin; Katherine Johnson; Paul Roth; James A. Westfall

    2012-01-01

    The Forest Inventory and Analysis Program of the Northern Research Station (NRS-FIA) has implemented new Advance Tree Seedling Regeneration (ATSR) protocols that include measurements of seedlings down to 2 inches in height. The addition of ATSR protocols is part of an evaluation of NRS-FIA Phase 3 indicator variables to increase sampling intensity from 1/96,000 acres...

  14. Role of the immune system in regeneration and its dynamic interplay with adult stem cells.

    Science.gov (United States)

    Abnave, Prasad; Ghigo, Eric

    2018-04-09

    The immune system plays an indispensable role in the process of tissue regeneration following damage as well as during homeostasis. Inflammation and immune cell recruitment are signs of early onset injury. At the wound site, immune cells not only help to clear debris but also secrete numerous signalling molecules that induce appropriate cell proliferation and differentiation programmes essential for successful regeneration. However, the immune system does not always perform a complementary role in regeneration and several reports have suggested that increased inflammation can inhibit the regeneration process. Successful regeneration requires a balanced immune cell response, with the recruitment of accurately polarised immune cells in an appropriate quantity. The regulatory interactions of the immune system with regeneration are not unidirectional. Stem cells, as key players in regeneration, can also modulate the immune system in several ways to facilitate regeneration. In this review, we will focus on recent research demonstrating the key role of immune system in the regeneration process as well as the immunomodulatory effects of stem cells. Finally, we propose that research investigating the interplay between the immune system and stem cells within highly regenerating animals can benefit the identification of the key interactions and molecules required for successful regeneration. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Potential Use of Stem Cells for Kidney Regeneration

    Directory of Open Access Journals (Sweden)

    Takashi Yokoo

    2011-01-01

    Full Text Available Significant advances have been made in stem cell research over the past decade. A number of nonhematopoietic sources of stem cells (or progenitor cells have been identified, including endothelial stem cells and neural stem cells. These discoveries have been a major step toward the use of stem cells for potential clinical applications of organ regeneration. Accordingly, kidney regeneration is currently gaining considerable attention to replace kidney dialysis as the ultimate therapeutic strategy for renal failure. However, due to anatomic complications, the kidney is believed to be the hardest organ to regenerate; it is virtually impossible to imagine such a complicated organ being completely rebuilt from pluripotent stem cells by gene or chemical manipulation. Nevertheless, several groups are taking on this big challenge. In this manuscript, current advances in renal stem cell research are reviewed and their usefulness for kidney regeneration discussed. We also reviewed the current knowledge of the emerging field of renal stem cell biology.

  16. Regeneration of desiccants with solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Ghate, S.R.; Butts, C.L.; Lown, J.B.

    1985-01-01

    Saturated silica gel was regenerated with solar energy. This paper describes the experimental set-up for silica gel regeneration and data collection. The regenerated silica gel can be used to dry high moisture in-shell pecans.

  17. Variations of Mercury Concentrations in American Beech Foliage over a Growing Season

    Science.gov (United States)

    Stinson, I.; Tsui, M. T. K.; Chow, A. T.

    2017-12-01

    Accumulation of atmospheric gaseous mercury (Hg) in foliage is well known, however, a small fraction of Hg always exists as highly bioavailable methylmercury (MeHg) in foliage but the source of MeHg in foliage is unknown. Recent studies suggested in-vivo Hg methylation in foliage while others suggested external inputs (e.g., precipitation) as sources of MeHg in foliage. This study assesses the accumulation of total Hg and MeHg within the foliage of a small sample set of American Beech trees, one of the common tree species in the east coast and the study site is located within the campus of University of North Carolina - Greensboro, over the growing season in 2017 (spring, summer, and fall). In addition, this study evaluates the Hg concentrations in foliage as related to other physiological parameters (e.g., stomatal density, leaf area, chlorophyll, and carbon/nitrogen content) and the changes in environmental characteristics (e.g., sunlight) over the growing season. For this investigation, five American Beech trees with varying characteristics (height, age, and location) were selected. On a biweekly basis, starting late April 2017, foliage samples were collected and composited from different positions on each tree. For the samples processed to date, our results indicate that total Hg accumulation is occurring for all five trees with an initial mean value of 5.79 ng/g, increasing to a mean value of 13.9 ng/g over a ten-week period. Coincidentally, there has been a similar increase in chlorophyll (a+b) concentrations for the foliage, and there is a strong, positive relationship between chlorophyll and total-Hg concentrations. However, we found no relationships between total Hg concentrations and stomatal density of foliage or carbon/nitrogen content. This study is still ongoing and will continue through the end of the growing season in 2017. Additionally, from the same sample sets, besides total Hg analysis and other ancillary parameters in foliage, MeHg analysis

  18. Production dynamics of fine roots in beech forests: possible mechanism of resource allocation between above- and below-ground production

    Science.gov (United States)

    Nakahata, R.; Osawa, A.; Naramoto, M.; Mizunaga, H.; Sato, M.

    2017-12-01

    The masting phenomenon that seed production has large annual variation with spatial synchrony appears generally in beeches. Therefore, net primary production and carbon allocation mechanism in beech forests may differ among several years in relation to annual variation of seed production. On the other hand, fine roots play key roles in carbon dynamics and nutrient and water acquisition of an ecosystem. Evaluation of fine root dynamics is essential to understand long-term dynamics of production in forest ecosystems. Moreover, the influence of mast seeding on resource allocation should be clarified in such beech forests. The aim of this study is to clarify possible relationships between the patterns of above- and below-ground production in relation to the masting events using observation data of litter fall and fine root dynamics. We applied the litter trap method and a minirhizotron method in a cool-temperate natural forest dominated by beech (Fagus crenata Blume). Ten litter traps were set from 2008 to 2016, then annual leaf and seed production were estimated. Four minirhizotron tubes were buried in Aug. 2008 and soil profiles were scanned monthly until Nov. 2016 during the periods of no snow covering. The scanned soil profiles were analyzed for calculating fine root production using the WinRHIZO Tron software. In the present study site, rich production of mast seeding occurred biennially and fine root production showed various seasonal patterns. There was no significant correlation between seed production and annual fine root production in the same year. However, seed production had a positive correlation with fine root production in autumn in the previous year and indicated a negative correlation with that in autumn in the current year. These results indicate that higher fine root production has led to increased nutrient acquisition, which resulted in rich seed production in the next year. It is also suppressed after the masting events due to shortage in

  19. Performance investigation on the ultrasonic atomization liquid desiccant regeneration system

    International Nuclear Information System (INIS)

    Yang, Zili; Zhang, Kaisheng; Hwang, Yunho; Lian, Zhiwei

    2016-01-01

    Highlights: • We applied ultrasonic atomization technology to boost liquid desiccant regeneration. • We established a novel UARS and made a thorough study on its performance. • We developed a performance prediction model for UARS and validated its accuracy. • The necessary regeneration temperature dropped significantly (4.4 °C) in UARS. • Energy consumption for regenerating desiccant was reduced greatly (60.4%) in UARS. - Abstract: Liquid desiccant dehumidification systems have accumulated considerable research interest in recent years for their great energy saving potential in buildings. Within the system, the regenerator recovering liquid desiccant plays a major role in its performance. When the ultrasonic atomization technology is applied to atomize the desiccant solution into numerous tiny droplets with diameters around 50 μm, the regeneration process could be greatly enhanced. To validate this approach, a novel ultrasonic atomization liquid desiccant regeneration system (UARS) was studied in this work. An Ideal Regeneration Model (IRM) was developed to predict the regeneration performance of the UARS. Additionally, thorough experiments were carried out to validate the model under different operating conditions of the desiccant solution and air stream. The model predicted values and the experimental results coincided, with the average deviation less than 7.9%. The performance of UARS was compared with other regeneration systems from the open literature, while a case study was conducted for the power consumption and energy saving potential of UARS. It was found that the ultrasonic atomization technology enabled utilization of lower-grade energy for desiccant regeneration with the regeneration temperature lowered as much as 4.4 °C. In addition, a considerable energy saving potential of up to 23.4% could be achieved by the UARS for regenerating per unit mass flow of desiccant solution, while the power consumption of the ultrasonic atomization system

  20. Manipulations to regenerate aspen ecosystems

    Science.gov (United States)

    Wayne D. Shepperd

    2001-01-01

    Vegetative regeneration of aspen can be initiated through manipulations that provide hormonal stimulation, proper growth environment, and sucker protection - the three elements of the aspen regeneration triangle. The correct course of action depends upon a careful evaluation of the size, vigor, age, and successional status of the existing clone. Soils and site...

  1. Heartbreak hotel: a convergence in cardiac regeneration.

    Science.gov (United States)

    Schneider, Michael D

    2016-05-01

    In February 2016, The Company of Biologists hosted an intimate gathering of leading international researchers at the forefront of experimental cardiovascular regeneration, with its emphasis on 'Transdifferentiation and Tissue Plasticity in Cardiovascular Rejuvenation'. As I review here, participants at the workshop revealed how understanding cardiac growth and lineage decisions at their most fundamental level has transformed the strategies in hand that presently energize the prospects for human heart repair. © 2016. Published by The Company of Biologists Ltd.

  2. The head-regeneration transcriptome of the planarian Schmidtea mediterranea

    Science.gov (United States)

    2011-01-01

    Background Planarian flatworms can regenerate their head, including a functional brain, within less than a week. Despite the enormous potential of these animals for medical research and regenerative medicine, the mechanisms of regeneration and the molecules involved remain largely unknown. Results To identify genes that are differentially expressed during early stages of planarian head regeneration, we generated a de novo transcriptome assembly from more than 300 million paired-end reads from planarian fragments regenerating the head at 16 different time points. The assembly yielded 26,018 putative transcripts, including very long transcripts spanning multiple genomic supercontigs, and thousands of isoforms. Using short-read data from two platforms, we analyzed dynamic gene regulation during the first three days of head regeneration. We identified at least five different temporal synexpression classes, including genes specifically induced within a few hours after injury. Furthermore, we characterized the role of a conserved Runx transcription factor, smed-runt-like1. RNA interference (RNAi) knockdown and immunofluorescence analysis of the regenerating visual system indicated that smed-runt-like1 encodes a transcriptional regulator of eye morphology and photoreceptor patterning. Conclusions Transcriptome sequencing of short reads allowed for the simultaneous de novo assembly and differential expression analysis of transcripts, demonstrating highly dynamic regulation during head regeneration in planarians. PMID:21846378

  3. Chitosan Based Regenerated Cellulose Fibers Functionalized with Plasma and Ultrasound

    Directory of Open Access Journals (Sweden)

    Urška Vrabič Brodnjak

    2018-04-01

    Full Text Available The great potential of regenerated cellulose fibers, which offer excellent possibilities as a matrix for the design of bioactive materials, was the lead for our research. We focused on the surface modification of fibers to improve the sorption properties of regenerated cellulose and biocomposite regenerated cellulose/chitosan fibers, which are on the market. The purpose of our investigation was also the modification of regenerated cellulose fibers with the functionalization by chitosan as a means of obtaining similar properties to biocomposite regenerated cellulose/chitosan fibers on the market. Argon gas plasma was used for fiber surface activation and chitosan adsorption. Ultrasound was also used as a treatment procedure for the surface activation of regenerated cellulose fibers and treatment with chitosan. Analyses have shown that ultrasonic energy or plasma change the accessibility of free functional groups, structure and reactivity, especially in regenerated cellulose fibers. Changes that occurred in the morphology and in the structure of fibers were also reflected in their physical and chemical properties. Consequently, moisture content, sorption properties and water retention improved.

  4. Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration

    Science.gov (United States)

    2016-04-01

    1 Award Number: W81XWH-11-2-0047 TITLE: Nanofiber Nerve Guide for Peripheral Nerve Repair and Regeneration PRINCIPAL INVESTIGATOR: Ahmet Höke...TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-11-2-0047 Nanofiber nerve guide for peripheral nerve repair and regeneration 5b. GRANT NUMBER...goal of this collaborative research project was to develop next generation engineered nerve guide conduits (NGCs) with aligned nanofibers and

  5. The potential of beech seedlings to adapt to low P availability in soil - plant versus microbial effects on P mobilising potential in the rhizosphere

    Science.gov (United States)

    Meller, Sonia; Frey, Beat; Frossard, Emmanuel; Spohn, Marie; Schack-Kirchner, Helmer; Luster, Jörg

    2016-04-01

    The objective of our work was to investigate to what extent tree seedlings (Fagus sylvatica) are able to adapt the process of P mobilisation in the rhizosphere according to P speciation in the soil. Such mobilisation activity can include root exudation of P mobilising compounds or stimulation of specific P mobilising soil microbes. We hypothesized that Fagus sylvatica seedlings can adapt their own activity based on their P nutritional status and genetic memory of how to react under a given nutritional situation. To test the hypothesis, we set up a cross-growth experiment with beech of different provenances growing in soil from their own provenance site and in soil differing in P availability. Experiments were performed as a greenhouse experiment, with temperature control and natural light, during one vegetation period in rhizoboxes . We used two acidic forest soils, contrasting in P availability, collected at field sites of the German research priority program "Ecosystem Nutrition". Juvenile trees were collected along with the soils at the sites and planted respectively. The occurrence of P mobilising compounds and available P in the rhizosphere and in bulk soil were measured during the active growth season of the plants. In particular, we assessed phosphatase activity, (measured with zymography and plate enzymatic assay at pH 4,6.5, and 11) carboxylates and phosphate (measured by application of ion exchange membranes to specific soil micro zones, and by microdialysis), and pH (mapping with optodes). Plant P nutrition status was assessed by total P, N/P, phosphatase activity, and metabolic (TCA extractable) P in the leaves. The P-nutritional status of the beech provenances differed markedly independent from the P status of the soil where they were actually grown during experiment. In particular, the juvenile trees from the site rich in mineral P were sufficient in P, while those from the P-poor site with mostly organic P, were deficient. Enzymatic activity at the

  6. Challenges of stem cell-based pulp and dentin regeneration: a clinical perspective.

    Science.gov (United States)

    Huang, George T-J; Al-Habib, Mey; Gauthier, Philippe

    2013-03-01

    There are two types of approaches to regenerate tissues: cell-based and cell-free. The former approach is to introduce exogenous cells into the host to regenerate tissues, and the latter is to use materials other than cells in an attempt to regenerate tissues. There has been a significant advancement in stem cell-based pulp and dentin regeneration research in the past few years. Studies in small and large animals have demonstrated that pulp/dentin-like tissues can be regenerated partially or completely in the root canal space with apical openings of 0.7-3.0 mm using dental pulp stem cells, including stem cells from apical papilla (SCAP) and subpopulations of pulp stem cells. Bone marrow mesenchymal stem cells (BMMSCs) and adipose tissue-derived MSCs (ADMSCs) have also been shown to regenerate pulp-like tissue. In contrast, the cell-free approach has not produced convincing evidence on pulp regeneration. However, one crucial concept has not been considered nor defined in the field of pulp/dentin regeneration and that is the critical size defect of dentin and pulp. Without such consideration and definition, it is difficult to predict or anticipate the extent of cell-free pulp regeneration that would occur. By reasoning, cell-free therapy is unlikely to regenerate an organ/tissue after total loss. Similarly, after a total loss of pulp, it is unlikely to regenerate without using exogenously introduced cells. A cell homing approach may provide a limited amount of tissue regeneration. Although stem cell-based pulp/dentin regeneration has shown great promise, clinical trials are difficult to launch at present. This article will address several issues that challenge and hinder the clinical applications of pulp/dentin regeneration which need to be overcome before stem cell-based pulp/dentin regeneration can occur in the clinic.

  7. Acoustic field modulation in regenerators

    Science.gov (United States)

    Hu, J. Y.; Wang, W.; Luo, E. C.; Chen, Y. Y.

    2016-12-01

    The regenerator is a key component that transfers energy between heat and work. The conversion efficiency is significantly influenced by the acoustic field in the regenerator. Much effort has been spent to quantitatively determine this influence, but few comprehensive experimental verifications have been performed because of difficulties in modulating and measuring the acoustic field. In this paper, a method requiring two compressors is introduced and theoretically investigated that achieves acoustic field modulation in the regenerator. One compressor outputs the acoustic power for the regenerator; the other acts as a phase shifter. A RC load dissipates the acoustic power out of both the regenerator and the latter compressor. The acoustic field can be modulated by adjusting the current in the two compressors and opening the RC load. The acoustic field is measured with pressure sensors instead of flow-field imaging equipment, thereby greatly simplifying the experiment.

  8. The Research Site Vrchslatina – an experimental design and the main aims

    Directory of Open Access Journals (Sweden)

    Konôpka Bohdan

    2013-09-01

    Full Text Available The research site “Vrchslatina” was established in the spring of 2009 with the aim of studying production processes and the structure of net primary productivity in young forest stands. The beech and spruce stands grown at the site were selected because they originated from natural regeneration and are nearly of the same age. In 2009, we established 5 research plots in each stand with the aim of measuring basic tree characteristics. Moreover, we excavated entire trees to construct allometric relations for the specific tree compartments. In the consecutive years (2010, 2011 and 2012, we also included grass communities dominated by Calamagrostis epigejos in our studies. Besides studying production processes of all tree compartments (i.e. for trees: foliages, branches, stem, coarse and fine roots, for grasses and herbs: below- and above-ground parts, we monitored several atmospheric characteristics, followed by soil characteristics and eventually added a measurement of soil respiration. The results indicated that forest stands (even though they were in their initial growth stages sequestrated much more carbon than the grass communities. Moreover, we proved the considerable influence of climatic conditions (especially the sum of precipitation in the particular years for net primary productivity.

  9. Molten salt pyrolysis of milled beech wood using an electrostatic precipitator for oil collection

    Directory of Open Access Journals (Sweden)

    Heidi S. Nygård

    2015-07-01

    Full Text Available A tubular electrostatic precipitator (ESP was designed and tested for collection of pyrolysis oil in molten salt pyrolysis of milled beech wood (0.5-2 mm. The voltage-current (V-I characteristics were studied, showing most stable performance of the ESP when N2 was utilized as inert gas. The pyrolysis experiments were carried out in FLiNaK and (LiNaK2CO3 over the temperature range of 450-600 ℃. The highest yields of pyrolysis oil were achieved in FLiNaK, with a maximum of 34.2 wt% at 500 ℃, followed by a decrease with increasing reactor temperature. The temperature had nearly no effect on the oil yield for pyrolysis in (LiNaK2CO3 (19.0-22.5 wt%. Possible hydration reactions and formation of HF gas during FLiNaK pyrolysis were investigated by simulations (HSC Chemistry software and measurements of the outlet gas (FTIR, but no significant amounts of HF were detected.

  10. Thermal conductivity at the amorphous-nanocrystalline phase transition in beech wood biocarbon

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Jezowski, A.; Ramirez-Rico, J.

    2014-05-01

    High-porosity samples of beech wood biocarbon (BE-C) were prepared by pyrolysis at carbonization temperatures T carb = 650, 1300, and 1600°C, and their resistivity ρ and thermal conductivity κ were studied in the 5-300 and 80-300 K temperature intervals. The experimental results obtained were evaluated by invoking X-ray diffraction data and information on the temperature dependences ρ( T) and κ( T) for BE-C samples prepared at T carb = 800, 1000, and 2400°C, which were collected by the authors earlier. An analysis of the κ( T carb) behavior led to the conclusion that the samples under study undergo an amorphous-nanocrystalline phase transition in the interval 800°C < T carb < 1000°C. Evaluation of the electronic component of the thermal conductivity revealed that the Lorentz number of the sample prepared at T carb = 2400°C exceeds by far the classical Sommerfeld value, which is characteristic of metals and highly degenerate semiconductors.

  11. Thermal conductivity of the amorphous and nanocrystalline phases of the beech wood biocarbon nanocomposite

    Science.gov (United States)

    Kartenko, N. F.; Orlova, T. S.; Parfen'eva, L. S.; Smirnov, B. I.; Smirnov, I. A.

    2014-11-01

    Natural composites (biocarbons) obtained by carbonization of beech wood at different carbonization temperatures T carb in the range of 800-2400°C have been studied using X-ray diffraction. The composites consist of an amorphous matrix and nanocrystallites of graphite and graphene. The volume fractions of the amorphous and nanocrystalline phases as functions of T carb have been determined. Temperature dependences of the phonon thermal conductivity κ( T) of the biocarbons with different temperatures T carb (1000 and 2400°C) have been analyzed in the range of 5-300 K. It has been shown that the behavior of κ( T) of the biocarbon with T carb = 1000°C is controlled by the amorphous phase in the range of 5-50 K and by the nanocrystalline phase in the range of 100-300 K. The character of κ( T) of the biocarbon with T carb = 2400°C is determined by the heat transfer (scattering) in the nanocrystalline phase over the entire temperature range of 5-300 K.

  12. Specific features of the electrical properties in partially graphitized porous biocarbons of beech wood

    Science.gov (United States)

    Popov, V. V.; Orlova, T. S.; Gutierrez-Pardo, A.; Ramirez-Rico, J.

    2015-09-01

    The electrical and galvanomagnetic properties of partially graphitized highly porous bioC(Ni) biocarbon matrices produced by pyrolysis (carbonization) of beech wood at temperatures T carb = 850-1600°C in the presence of a Ni-containing catalyst have been studied in comparison with their microstructural features. The temperature dependences of the resistivity, the magnetoresistance, and the Hall coefficient have been measured in the temperature range of 4.2-300 K in magnetic fields to 28 kOe. It has been shown that an additional graphite phase introduction into samples with T carb ≥ 1000°C results in an increase in the carrier mobility by a factor of 2-3, whereas the carrier (hole) concentration remains within ~1020 cm-3, as in biocarbons obtained without catalyst. An analysis of experimental data has demonstrated that the features of the conductivity and magnetoresistance of these samples are described by quantum corrections related to their structural features, i.e., the formation of a globular graphite phase of nano- and submicrometer sizes in the amorphous matrix. The quantum corrections to the conductivity decrease with increasing carbonization temperature, which indicates an increase in the degree of structure ordering and is in good agreement with microstructural data.

  13. Thermal conductivity of high-porosity biocarbon preforms of beech wood

    Science.gov (United States)

    Parfen'eva, L. S.; Orlova, T. S.; Kartenko, N. F.; Sharenkova, N. V.; Smirnov, B. I.; Smirnov, I. A.; Misiorek, H.; Jezowski, A.; Wilkes, T. E.; Faber, K. T.

    2010-06-01

    This paper reports on measurements performed in the temperature range 5-300 K for the thermal conductivity κ and electrical resistivity ρ of high-porosity (cellular pores) biocarbon preforms prepared by pyrolysis (carbonization) of beech wood in an argon flow at carbonization temperatures of 1000 and 2400°C. X-ray structure analysis of the samples has been performed at 300 K. The samples have revealed the presence of nanocrystallites making up the carbon matrices of these biocarbon preforms. Their size has been determined. For samples prepared at T carb = 1000 and 2400°C, the nanocrystallite sizes are found to be in the ranges 12-25 and 28-60 κ( T) are determined for the samples cut along and across the tree growth direction. The thermal conductivity κ increases with increasing carbonization temperature and nanocrystallite size in the carbon matrix of the sample. Thermal conductivity measurements conducted on samples of both types have revealed an unusual temperature dependence of the phonon thermal conductivity for amorphous materials. As the temperature increases from 5 to 300 K, it first increases in proportion to T, to transfer subsequently to ˜ T 1.5 scaling. The results obtained are analyzed.

  14. Dispersal of Airborne Pollen in Chatienshan Nature Reserve, Northern Taiwan, with Emphasis on Taiwan Beech

    Directory of Open Access Journals (Sweden)

    Chuan Ku

    2012-12-01

    Full Text Available In this first study on the pollen rain in natural forest in Taiwan using pollen traps, the dispersal patterns of airborne pollen were determined, with emphasis on Fagus hayatae and some major plant species, and the relationship between pollen assemblages and vegetation was elucidated. Seventeen pollen traps were installed on the western slope of Mt. Takai, northern Taiwan, from March 21 to May 10, 2008. Pollen and spores belonging to 37 families and 43 genera were identified. The results of correspondence analysis suggested differentiation of three vertical zones of pollen assemblages that corresponded to three vegetation types. Three patterns of occurrence were identified for the major pollen taxa, namely ubiquitous occurrence, local occurrence, and peak occurrence. The pollen influx of F. hayatae, a taxon characterized by local occurrence, was remarkably lower at a distance of over 200 m away from the pure stands. This suggests that pollen-mediated gene flow between the beech populations in Taiwan is unlikely. Besides providing basic data on the pollen dispersal of some important taxa in the middle altitudes of Taiwan, the present study also points out that caution should be taken in interpreting pollen percentage data from sediments.

  15. Natural and anthropogenic stress in spruce and beech ecosystems in the Solling project

    International Nuclear Information System (INIS)

    Murach, D.

    1989-01-01

    The investigations show that low Ca/Al-ratios in mineral soil horizons cause a shallow root system with spruce. But obviously other soil conditions expect acidification can also be responsible for a shallow root system. Additional investigations and field experiments have to find out the driving forces. A new phenomenon in fine root investigations are the low fine root concentrations in the uppermost mineral soil horizons. It is to be observed with spruce as well as with beech in stands with strong acidification of the top soil. Further experiments are needed to evaluate what are the main chemical variables (pH, heavy metals etc.) In this way soil acidification can cause reductions of fine root biomasses in subsoils as well as in uppermost soil horizons. These reductions can influence the response of trees to water stress. Relations to the symptoms of needle losses with spruce are likely. The close correlations between the chemistry of the soil, the roots and the needles indicate, that the yellowing symptoms of spruce trees, which were related to Mg-deficiency, are caused by Mg-deficiency in the soil. It is to be emphazised that it is not a pure Mg-deficiency. Ion antagonism to Al and especially to H in connection with fine root distribution are of main importance. (orig.)

  16. Fine root dynamics of mature European beech (Fagus sylvatica L.) as influenced by elevated ozone concentrations

    International Nuclear Information System (INIS)

    Mainiero, Raphael; Kazda, Marian; Haeberle, Karl-Heinz; Nikolova, Petia Simeonova; Matyssek, Rainer

    2009-01-01

    Fine root dynamics (diameter < 1 mm) in mature Fagus sylvatica, with the canopies exposed to ambient or twice-ambient ozone concentrations, were investigated throughout 2004. The focus was on the seasonal timing and extent of fine root dynamics (growth, mortality) in relation to the soil environment (water content, temperature). Under ambient ozone concentrations, a significant relationship was found between fine root turnover and soil environmental changes indicating accelerated fine root turnover under favourable soil conditions. In contrast, under elevated ozone, this relationship vanished as the result of an altered temporal pattern of fine root growth. Fine root survival and turnover rate did not differ significantly between the different ozone regimes, although a delay in current-year fine root shedding was found under the elevated ozone concentrations. The data indicate that increasing tropospheric ozone levels can alter the timing of fine root turnover in mature F. sylvatica but do not affect the turnover rate. - Doubling of ozone concentrations in mature European beech affected the seasonal timing of fine root turnover rather than the turnover rate.

  17. Effects of wood ash on soil solution and chemistry of leaves in a beech stand

    International Nuclear Information System (INIS)

    Tothova, Slavka

    2005-01-01

    The short-term effects of wood ash fertilization on chemistry of soil solution and leaves were investigated in 4-year-old beech stand (Fagus sylvatica L.) on dystric cambisol in Central Spis. Four plots - the control plot and three plots with different ash treatments (different dose, date and method of application) were established. Plate lysimeters were installed under the upper layer of soil in depth 2 cm and 20 cm on the control plot and plot P1 with addition of wood ash 5 t/ha on the whole surface. Soil solution was collected in May - October 2002 every two weeks. Composite samples, which represent a one - month period, were analysed for pH, K, Ca, Mg, and NO 3 - . The leaves were collected 4 or 10 months after the treatment and analysed on Ca, K, Mg, P, S, N and heavy metals Cd, Pb, Cr and Hg. In the ash treatment the content of macronutrient increased (mainly K, Ca). Addition of ash did not increase of the content heavy metal in leaves

  18. Major Changes in Growth Rate and Growth Variability of Beech (Fagus sylvatica L. Related to Soil Alteration and Climate Change in Belgium

    Directory of Open Access Journals (Sweden)

    Nicolas Latte

    2016-08-01

    Full Text Available Global change—particularly climate change, forest management, and atmospheric deposition—has significantly altered forest growing conditions in Europe. The influences of these changes on beech growth (Fagus sylvatica L. were investigated for the past 80 years in Belgium, using non-linear mixed effects models on ring-width chronologies of 149 mature and dominant beech trees (87–186 years old. The effects of the developmental stage (i.e., increasing tree size were filtered out in order to focus on time-dependent growth changes. Beech radial growth was divided into a low-frequency signal (=growth rate, mainly influenced by forest management and atmospheric deposition, and into a high-frequency variability (≈mean sensitivity, mainly influenced by climate change. Between 1930 and 2008, major long-term and time-dependent changes were highlighted. The beech growth rate has decreased by about 38% since the 1950–1960s, and growth variability has increased by about 45% since the 1970–1980s. Our results indicate that (1 before the 1980s, beech growth rate was not predominantly impacted by climate change but rather by soil alteration (i.e., soil compaction and/or nitrogen deposition; and (2 since the 1980s, climate change induced more frequent and intense yearly growth reductions that amplified the growth rate decrease. The highlighted changes were similar in the two ecoregions of Belgium, although more pronounced in the lowlands than in the uplands.

  19. Results from neutral kaon regeneration at high energies

    International Nuclear Information System (INIS)

    Hladky, J.

    1976-01-01

    Experimental neutral kaon regeneration results at Serpukhov energies up to 50 GeV are presented, including the coherent regeneration on hydrogen, deuterium and carbon regenerators and elastic regeneration on deuterium and carbon regenerators. (author)

  20. Environment vs. Plant Ontogeny: Arthropod Herbivory Patterns on European Beech Leaves along the Vertical Gradient of Temperate Forests in Central Germany

    Directory of Open Access Journals (Sweden)

    Stephanie Stiegel

    2018-01-01

    Full Text Available Environmental and leaf trait effects on herbivory are supposed to vary among different feeding guilds. Herbivores also show variability in their preferences for plant ontogenetic stages. Along the vertical forest gradient, environmental conditions change, and trees represent juvenile and adult individuals in the understorey and canopy, respectively. This study was conducted in ten forests sites in Central Germany for the enrichment of canopy research in temperate forests. Arthropod herbivory of different feeding traces was surveyed on leaves of Fagus sylvatica Linnaeus (European beech; Fagaceae in three strata. Effects of microclimate, leaf traits, and plant ontogenetic stage were analyzed as determining parameters for herbivory. The highest herbivory was caused by exophagous feeding traces. Herbivore attack levels varied along the vertical forest gradient for most feeding traces with distinct patterns. If differences of herbivory levels were present, they only occurred between juvenile and adult F. sylvatica individuals, but not between the lower and upper canopy. In contrast, differences of microclimate and important leaf traits were present between the lower and upper canopy. In conclusion, the plant ontogenetic stage had a stronger effect on herbivory than microclimate or leaf traits along the vertical forest gradient.

  1. Tree regeneration by seed in bottomland hardwood forests: A review

    Science.gov (United States)

    Kroschel, Whitney A.; King, Sammy L.; Keim, Richard F.

    2016-01-01

    Bottomland hardwood forests (BLH) are found in temperate, humid regions of the southeastern US, primarily on alluvial floodplains adjacent to rivers. Altered hydrology in rivers and floodplains has caused changes in stand development and species composition of BLHs. We hypothesize that the driving mechanisms behind these changes are related to the regeneration process because of the complexity of recruitment and the vulnerability of species at that age in development. Here we review the state of our understanding regarding BLH regeneration, and identify potential bottlenecks throughout the stages of seed production, seed dispersal, germination, establishment, and survival. Our process-level understanding of regeneration by seed in BLHs is rudimentary, thus limiting our ability to predict the effects of hydrologic alterations on species composition. By focusing future research on the appropriate stages of regeneration, we can better understand the sources of forest-community transitions across the diverse range of BLH systems.

  2. EVALUATING THE CULTURE-LED REGENERATION

    Directory of Open Access Journals (Sweden)

    D'Angelo Francesca

    2010-12-01

    Full Text Available The aim of the paper is to propose a new approach to urban planning, evaluating the culture-led regeneration processes. In the last few years, the cultural turn in urban planning played a central role in the urban studies. In this way we try to elaborate a more robust perspective interpreting the complex phenomenology emerging from the culture-led regeneration processes. Within the concept of complexity we discuss about the metabolic process that are the processes necessary to transform energy, material and information in goods and service functional to the complex urban system life. The approach that will be employed is the MuSIASEM that is based on several novel concept and an innovative methods never applied in this research field.

  3. Biomimetic electrospun nanofibers for tissue regeneration

    International Nuclear Information System (INIS)

    Liao, Susan; Li Bojun; Ma Zuwei; Wei He; Chan Casey; Ramakrishna, Seeram

    2006-01-01

    Nanofibers exist widely in human tissue with different patterns. Electrospinning nanotechnology has recently gained a new impetus due to the introduction of the concept of biomimetic nanofibers for tissue regeneration. The advanced electrospinning technique is a promising method to fabricate a controllable continuous nanofiber scaffold similar to the natural extracellular matrix. Thus, the biomedical field has become a significant possible application field of electrospun fibers. Although electrospinning has developed rapidly over the past few years, electrospun nanofibers are still at a premature research stage. Further comprehensive and deep studies on electrospun nanofibers are essential for promoting their biomedical applications. Current electrospun fiber materials include natural polymers, synthetic polymers and inorganic substances. This review briefly describes several typically electrospun nanofiber materials or composites that have great potential for tissue regeneration, and describes their fabrication, advantages, drawbacks and future prospects. (topical review)

  4. Sensory hair cell death and regeneration in fishes

    Directory of Open Access Journals (Sweden)

    Jerry D. Monroe

    2015-04-01

    Full Text Available Sensory hair cells are specialized mechanotransductive receptors required for hearing and vestibular function. Loss of hair cells in humans and other mammals is permanent and causes reduced hearing and balance. In the early 1980’s, it was shown that hair cells continue to be added to the inner ear sensory epithelia in cartilaginous and bony fishes. Soon thereafter, hair cell regeneration was documented in the chick cochlea following acoustic trauma. Since then, research using chick and other avian models has led to great insights into hair cell death and regeneration. However, with the rise of the zebrafish as a model organism for studying disease and developmental processes, there has been an increased interest in studying sensory hair cell death and regeneration in its lateral line and inner ears. Advances derived from studies in zebrafish and other fish species include understanding the effect of ototoxins on hair cells and finding otoprotectants to mitigate ototoxin damage, the role of cellular proliferation versus direct transdifferentiation during hair cell regeneration, and elucidating cellular pathways involved in the regeneration process. This review will summarize research on hair cell death and regeneration using fish models, indicate the potential strengths and weaknesses of these models, and discuss several emerging areas of future studies.

  5. Muscle regeneration in mitochondrial myopathies

    DEFF Research Database (Denmark)

    Krag, T O; Hauerslev, S; Jeppesen, T D

    2013-01-01

    Mitochondrial myopathies cover a diverse group of disorders in which ragged red and COX-negative fibers are common findings on muscle morphology. In contrast, muscle degeneration and regeneration, typically found in muscular dystrophies, are not considered characteristic features of mitochondrial...... myopathies. We investigated regeneration in muscle biopsies from 61 genetically well-defined patients affected by mitochondrial myopathy. Our results show that the perturbed energy metabolism in mitochondrial myopathies causes ongoing muscle regeneration in a majority of patients, and some were even affected...

  6. Immunoglobulin E-mediated sensitization to pine and beech dust in relation to wood dust exposure levels and respiratory symptoms in the furniture industry.

    Science.gov (United States)

    Schlünssen, Vivi; Kespohl, Sabine; Jacobsen, Gitte; Raulf-Heimsoth, Monika; Schaumburg, Inger; Sigsgaard, Torben

    2011-03-01

    Wood dust exposure may cause Immunoglobulin E (IgE)-mediated allergic diseases. Our objectives were to estimate pine and beech dust sensitization rates among woodworkers and a reference group, explore the association between exposure and sensitization and between sensitization and respiratory symptoms, and finally investigate the impact of proteinogenic specific IgE (sIgE) epitopes on respiratory symptoms. In a Danish study among 52 furniture factories and 2 reference factories, we evaluated the workers' asthma and rhinitis status using questionnaires and blood samples collected from 1506 woodworkers and 195 references. Workers with asthma symptoms (N=298), a random study sample (N=399) and a random rhinitis sample (N=100) were evaluated for IgE-mediated sensitization to pine and beech dust. The prevalence of pine and beech sensitization among current woodworkers was 1.7 and 3.1%, respectively. No differences in sensitization rates were found between woodworkers and references, but the prevalence of wood dust sensitization was dose-dependently associated with the current level of wood dust exposure. No relation was observed between wood dust sensitization per se and respiratory symptoms. Only symptomatic subjects had proteinogenic IgE epitopes to pine. Increased odds ratios for sIgE based on proteinogenic epitopes to beech and respiratory symptoms were found, although they were not statistically significant. Sensitization rates to pine and beech were the same for woodworkers and references but dependent on the current wood dust exposure level. The importance of beech and pine wood sensitization is limited, but may be of clinical significance for a few workers if the IgE epitopes are proteinogenic.

  7. Sap flux density and stomatal conductance of European beech and common oak trees in pure and mixed stands during the summer drought of 2003

    Science.gov (United States)

    Jonard, F.; André, F.; Ponette, Q.; Vincke, C.; Jonard, M.

    2011-10-01

    SummarySap flux density of European beech and common oak trees was determined from sap flow measurements in pure and mixed stands during the summer drought of 2003. Eight trees per species and per stand were equipped with sap flow sensors. Soil water content was monitored in each stand at different depths by using time-domain reflectometry (TDR). Leaf area index and vertical root distribution were also investigated during the growing season. From sap flux density ( SFD) data, mean stomatal conductance of individual trees ( G s) was calculated by inverting the Penman-Monteith equation. Linear mixed models were developed to analyse the effects of species and stand type (pure vs. mixed) on SFD and G s and on their sensitivity to environmental variables (vapour pressure deficit ( D), incoming solar radiation ( R G), and relative extractable water ( REW)). For reference environmental conditions, we did not find any tree species or stand type effects on SFD. The sensitivity of SFD to D was higher for oak than for beech in the pure stands ( P sapwood-to-leaf area ratio compared to oak. The sensitivity of G s to REW was higher for beech than for oak and was ascribed to a higher vulnerability of beech to air embolism and to a more sensitive stomatal regulation. The sensitivity of beech G s to REW was lower in the mixed than in the pure stand, which could be explained by a better sharing of the resources in the mixture, by facilitation processes (hydraulic lift), and by a rainfall partitioning in favour of beech.

  8. Regenerable Carbon Filter, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A Regenerable Carbon Filter (RCF) is proposed for the removal of carbonaceous particulate matter produced in Environmental Control and Life Support (ECLS) processes....

  9. Treefall gap disturbance in an old-growth beech forest in southwestern Japan by a catastrophic typhoon

    International Nuclear Information System (INIS)

    Ida, Hideyuki

    2000-01-01

    In 1991, the catastrophic Typhoon 9119 created many treefall gaps in an old-growth beech (Fagus crenata) forest on Mt. Garyu, southwestern Japan. In a 3.3-ha plot, the density and basal area of fatally damaged trunks (DBH ≥ 20 cm) were 29.1 trunks/ha (16.9% of all pre-typhoon trunks) and 9.1 m 2 /ha. (24.4% of total pre-typhoon basal area), respectively. Many of the dominant beech were lost and larger trunks were damaged. The pre- and post-typhoon DBH distribution both had an inverse J-shape. Spatial distribution of living trunks was not random but clustered irrespective of typhoon damage or DBH size, suggesting that the stand structure of the study plot would be an unusual one as compared with the previous study stands in Japanese beech forests. The death of pre-typhoon trunks, seemed to die standing or to be killed by snap-off, occurred singly; however, the typhoon fatally damaged many clustered trunks at the same time. Uprooting was the most frequent cause of gaps created by the typhoon. The intermediate DBH size class (40 - 70 cm) would be more likely to be uprooted than snapped-off. The DBH distribution of snap-off may reflect the total pre-typhoon trunk distribution. Branch-fall had a flat DBH distribution. Uprooting might have a clustered distribution, while snap-off and branch-fall both had random distributions. The smaller trunks of snap-off and branch-fall seemed to result from injuries caused by the fall of larger trunks

  10. The Decline of Vitality Caused by Increasing Drought in a Beech Provenance Trial Predicted by Juvenile Growth

    Directory of Open Access Journals (Sweden)

    Anikó Horváth

    2016-06-01

    Full Text Available Background and Purpose: Due to rapidly changing environmental conditions, locally adapted tree populations are likely to experience climate conditions to which they are not well adapted. Common garden experiments provide a powerful tool for studying adaptive responses in changing climates. Out of the 1998 series of international beech provenance trials, one experiment was established in Bucsuta, SW Hungary. Because of its peripheral location, this is probably the most apposite site in the experimental series to study and predict responses of populations to sudden climatic changes, simulated by transfer. Material and Methods: 15-year diameter data of 28 beech populations from different regions of Europe were used to mimic responses to climate change by transplantation to the test site. The effect of 17 climate variables and five derived climate indices on growth have been compared, while Ellenberg drought index (EQ was selected for calculating a linear regression (transfer function to project a growth trend for future climate change. Results: Out of the bioclimatic variables, Ellenberg drought index at the location of the origin of provenances has shown the best correlation with 15-year diameter. The regression of growth vs. the ecodistance of transfer (difference between data of the trial site and of the site of origin, expressed in EQ, explained 25% of the total variation between provenances and indicated a clear trend of declining performance with the increasing change of climate the populations were adapted to. Conclusion: Negative effect of rapid climate change on beech populations cannot be denied, and the results draw attention to the importance of using appropriate planting stock matching with future climate conditions at the planting site.

  11. How closely does stem growth of adult beech (Fagus sylvatica) relate to net carbon gain under experimentally enhanced ozone stress?

    International Nuclear Information System (INIS)

    Kitao, Mitsutoshi; Winkler, J. Barbro; Löw, Markus; Nunn, Angela J.; Kuptz, Daniel; Häberle, Karl-Heinz; Reiter, Ilja M.; Matyssek, Rainer

    2012-01-01

    The hypothesis was tested that O 3 -induced changes in leaf-level photosynthetic parameters have the capacity of limiting the seasonal photosynthetic carbon gain of adult beech trees. To this end, canopy-level photosynthetic carbon gain and respiratory carbon loss were assessed in European beech (Fagus sylvatica) by using a physiologically based model, integrating environmental and photosynthetic parameters. The latter were derived from leaves at various canopy positions under the ambient O 3 regime, as prevailing at the forest site (control), or under an experimental twice-ambient O 3 regime (elevated O 3 ), as released through a free-air canopy O 3 fumigation system. Gross carbon gain at the canopy-level declined by 1.7%, while respiratory carbon loss increased by 4.6% under elevated O 3 . As this outcome only partly accounts for the decline in stem growth, O 3 -induced changes in allocation are referred to and discussed as crucial in quantitatively linking carbon gain with stem growth. - Highlights: ► We model O 3 -induced changes in the photosynthetic carbon gain of adult beech trees. ► Elevated O 3 decreases gross carbon gain but increases respiratory carbon loss. ► Reduction in net carbon gain only partly accounts for the decline in stem growth. ► O 3 effects on the whole-tree allocation is crucial in addition to carbon gains. - Reduction in net carbon gain at the canopy level only partly accounts for the decline in stem growth under elevated ozone.

  12. Projected effects of climate change on the carbon stocks of European beech (Fagus sylvatica L. forests in Zala County, Hungary

    Directory of Open Access Journals (Sweden)

    Somogyi Zoltán

    2016-03-01

    Full Text Available Recent studies suggest that climate change will lead to the local extinction of many tree species from large areas during this century, affecting the functioning and ecosystem services of many forests. This study reports on projected carbon losses due to the assumed local climate change-driven extinction of European beech (Fagus sylvatica L. from Zala County, South-Western Hungary, where the species grows at the xeric limit of its distribution. The losses were calculated as a difference between carbon stocks in climate change scenarios assuming an exponentially increasing forest decline over time, and those in a baseline scenario assuming no climate change. In the climate change scenarios, three different sets of forest management adaptation measures were studied: (1 only harvesting damaged stands, (2 additionally salvaging dead trees that died due to climate change, and (3 replacing, at an increasing rate over time, beech with sessile oak (Quercus petraea Matt. Lieb. after final harvest. Projections were made using the open access carbon accounting model CASMOFOR based on modeling or assuming effects of climate change on mortality, tree growth, root-to-shoot ratio and decomposition rates. Results demonstrate that, if beech disappears from the region as projected by the end of the century, over 80% of above-ground biomass carbon, and over 60% of the carbon stocks of all pools (excluding soils of the forests will be lost by 2100. Such emission rates on large areas may have a discernible positive feedback on climate change, and can only partially be offset by the forest management adaptation measures.

  13. Plasma skin regeneration technology.

    Science.gov (United States)

    Bogle, M A

    2006-09-01

    Plasma skin regeneration (PSR) technology uses energy delivered from plasma rather than light or radiofrequency. Plasma is the fourth state of matter in which electrons are stripped from atoms to form an ionized gas. The plasma is emitted in a millisecond pulse to deliver energy to target tissue upon contact without reliance on skin chromophores. The technology can be used at varying energies for different depths of effect, from superficial epidermal sloughing to deeper dermal heating. With the Portrait PSR device (Rhytec, Inc.) there are three treatment guidelines termed PSR1, PSR2, and PSR3. The PSR1 protocol uses a series of low-energy treatments (1.0,1.2 Joules) spaced 3 weeks apart. The PSR2 protocol uses one high-energy pass (3.0, 4.0 Joules) performed in a single treatment, and the PSR3 protocol uses two high-energy passes (3.0 4.0 Joules) performed in a single treatment. All protocols improve fine lines, textural irregularities, and dyspigmentation; however, skin tightening is probably more pronounced with the high-energy treatments.

  14. Certified reference materials - beech leaves and spruce needles - for the quality control in monitoring damage in forests by acid deposition

    Energy Technology Data Exchange (ETDEWEB)

    Maier, E A; Griepink, B [Commission of the European Communities, Brussels (Belgium). Community Bureau of Reference; Muntau, H [Commission of the European Communities, Ispra (Italy). Joint Research Centre

    1989-12-01

    The chemical determination of various elements in leaves or needles allows to establish the damage caused by acid deposition. To control the quality of such determinations the Community Bureau of Reference (BCR) produced two Certified Reference Materials: Beech leaves (CRM No. 100) and Spruce needles (CRM No. 101). After a careful preparation procedure, a homogeneity study and a long term stability study, the materials were certified for: Cl, N, P and S in CRM No. 100, Al, Ca, Cl, Mg, Mn, N, P, S and Zn in CRM No. 101. Indicative values on the content of 19 majors and trace elements are also reported. (orig.).

  15. Determination of the suitability of chips from selected hardwoods for the production of furfural and charcoal. [Birches, beeches, oaks, alders

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowski, Z

    1979-01-01

    Debarked, cut beech, birch, alder, and oak residues from forestry and woodworking operations contain 16.56-19.73% pentosans and as such can be used for hydrolysis to furfural (I). The hydrolytic residue (mostly lignocellulose) can be carbonized at 400 degrees to charcoal. The hydrolysis is carried out continuously with steam at 250-300 degrees and 1.18 MPa. The residue chips are first soaked in water at 90 degrees for 4 hours and then fed into the hydrolyzer countercurrently to the steam. The yields of I are 5-6% and the yields of charcoal are approximately 20% on the chip weight.

  16. Changes in phenology and the influence on the carbon sequestration in a Danish beech forest over 20 years

    DEFF Research Database (Denmark)

    Pilegaard, Kim; Ibrom, Andreas

    Observations of carbon sequestration in a Danish beech forest over the last 20 years have shown a steady increase in NEE. Earlier studies (Pile- gaard et al. 2011) have shown, that about half of the increase can be attributed to an increase in the growing season length. The growing sea- son has...... 6 years using the R package Phenopix (Filippa et al. 2016). The new data is compared with CUP and LP to give more detailed information on the phenology. The information is used to examine the evolution of net ecosystem exchange (NEE) over the 20 year period....

  17. Two years of continuous CO2 eddy-flux measurements over a Danish beech forest

    DEFF Research Database (Denmark)

    Pilegaard, K.; Hummelshøj, P.; Jensen, N.O.

    2001-01-01

    As part of the EUROFLUX network a long-term monitoring station for fluxes of CO2 and water vapour has been established in an 80-year old beech forest in Denmark. The station has been in continuous operation since June 1996 and will be so at least to the end of 2002. A primary goal of EUROFLUX...... summer of 1997 and an average soil and air temperature, respectively, 1.2 and 1.6 degreesC higher than the first year. The ecosystem photosynthetic assimilation was slightly higher during the second year, mainly caused by increased incoming radiation. (C) 2001 Elsevier Science B.V. All nights reserved....

  18. Regeneration mechanisms in Syllidae (Annelida)

    Science.gov (United States)

    Ribeiro, Rannyele P.

    2018-01-01

    Abstract Syllidae is one of the most species‐rich groups within Annelida, with a wide variety of reproductive modes and different regenerative processes. Syllids have striking ability to regenerate their body anteriorly and posteriorly, which in many species is redeployed during sexual (schizogamy) and asexual (fission) reproduction. This review summarizes the available data on regeneration in syllids, covering descriptions of regenerative mechanisms in different species as well as regeneration in relation to reproductive modes. Our survey shows that posterior regeneration is widely distributed in syllids, whereas anterior regeneration is limited in most of the species, excepting those reproducing by fission. The latter reproductive mode is well known for a few species belonging to Autolytinae, Eusyllinae, and Syllinae. Patterns of fission areas have been studied in these animals. Deviations of the regular regeneration pattern or aberrant forms such as bifurcated animals or individuals with multiple heads have been reported for several species. Some of these aberrations show a deviation of the bilateral symmetry and antero‐posterior axis, which, interestingly, can also be observed in the regular branching body pattern of some species of syllids. PMID:29721325

  19. Immunology Guides Skeletal Muscle Regeneration

    Directory of Open Access Journals (Sweden)

    F. Andrea Sass

    2018-03-01

    Full Text Available Soft tissue trauma of skeletal muscle is one of the most common side effects in surgery. Muscle injuries are not only caused by accident-related injuries but can also be of an iatrogenic nature as they occur during surgical interventions when the anatomical region of interest is exposed. If the extent of trauma surpasses the intrinsic regenerative capacities, signs of fatty degeneration and formation of fibrotic scar tissue can occur, and, consequentially, muscle function deteriorates or is diminished. Despite research efforts to investigate the physiological healing cascade following trauma, our understanding of the early onset of healing and how it potentially determines success or failure is still only fragmentary. This review focuses on the initial physiological pathways following skeletal muscle trauma in comparison to bone and tendon trauma and what conclusions can be drawn from new scientific insights for the development of novel therapeutic strategies. Strategies to support regeneration of muscle tissue after injury are scarce, even though muscle trauma has a high incidence. Based on tissue specific differences, possible clinical treatment options such as local immune-modulatory and cell therapeutic approaches are suggested that aim to support the endogenous regenerative potential of injured muscle tissues.

  20. Specific features of electrical properties of porous biocarbons prepared from beech wood and wood artificial fiberboards

    Science.gov (United States)

    Popov, V. V.; Orlova, T. S.; Magarino, E. Enrique; Bautista, M. A.; Martínez-Fernández, J.

    2011-02-01

    This paper reports on comparative investigations of the structural and electrical properties of biomorphic carbons prepared from natural beech wood, as well as medium-density and high-density fiberboards, by means of carbonization at different temperatures T carb in the range 650-1000°C. It has been demonstrated using X-ray diffraction analysis that biocarbons prepared from medium-density and high-density fiberboards at all temperatures T carb contain a nanocrystalline graphite component, namely, three-dimensional crystallites 11-14 Å in size. An increase in the carbonization temperature T carb to 1000°C leads to the appearance of a noticeable fraction of two-dimensional graphene particles with the same sizes. The temperature dependences of the electrical resistivity ρ of the biomorphic carbons have been measured and analyzed in the temperature range 1.8-300 K. For all types of carbons under investigation, an increase in the carbonization temperature T carb from 600 to 900°C leads to a change in the electrical resistivity at T = 300 K by five or six orders of magnitude. The dependences ρ( T) for these materials are adequately described by the Mott law for the variable-range hopping conduction. It has been revealed that the temperature dependence of the electrical resistivity exhibits a hysteresis, which has been attributed to thermomechanical stresses in an inhomogeneous structure of the biocarbon prepared at a low carbonization temperature T carb. The crossover to the conductivity characteristic of disordered metal systems is observed at T carb ≳ 1000°C.

  1. Harvested wood products and carbon sink in a young beech high forest

    Directory of Open Access Journals (Sweden)

    Pilli R

    2008-03-01

    Full Text Available According to art. 3.4 of the Kyoto Protocol (KP, Italy has elected forest management as additional human-induced activity to attain the goal of reduction in greenhouse gas emissions. The whole forest area not subjected to afforestation, reforestation or deforestation processes since 1990 will be considered as managed forest. In order to analyse different management strategies, the Carbon-Pro Project, involving 9 partners of the European CADSES area, considered a young beech high forest (ex-coppice, defined as "transitory silvicultural system" as a common case study for the Pre-alps region. Using data collected with forest plans during the period 1983 - 2005, aboveground and belowground forest carbon stock and sink of a specific forest compartment were estimated by the Carbon Stock Method proposed by the IPCC Guidelines. In order to apply this approach 41 trees were cut and a species-specific allometric equation was developed. Considering the aboveground tree biomass, the carbon sink amounts to 1.99 and 1.84 Mg C ha-1 y-1 for the period 1983 - 1994 and 1994 - 2005 respectively. Adding the belowground tree biomass, the estimated sink amounts to 2.59 and 2.39 Mg C ha-1 y-1 for each period. Taking the harvested wood products (firewood, the total carbon sequestration during the second period is 0.16 Mg C ha-1 y-1. The case study highlights the possible rules for the different management strategies. In effect, the utilisation of the entire increase in aboveground biomass as firewood gives an energy substitution effect but, according to the Marrakesh Accords, it cannot be accounted for the KP. On the other hand, an accumulation strategy gives the maximum possible carbon absorption and retention.

  2. Stoichiometric controls of nitrogen and phosphorus cycling in decomposing beech leaf litter.

    Science.gov (United States)

    Mooshammer, Maria; Wanek, Wolfgang; Schnecker, Jörg; Wild, Birgit; Leitner, Sonja; Hofhansl, Florian; Blöchl, Andreas; Hämmerle, Ieda; Frank, Alexander H; Fuchslueger, Lucia; Keiblinger, Katharina M; Zechmeister-Boltenstern, Sophie; Richter, Andreas

    2012-04-01

    Resource stoichiometry (C:N:P) is an important determinant of litter decomposition. However, the effect of elemental stoichiometry on the gross rates of microbial N and P cycling processes during litter decomposition is unknown. In a mesocosm experiment, beech (Fagus sylvatica L.) litter with natural differences in elemental stoichiometry (C:N:P) was incubated under constant environmental conditions. After three and six months, we measured various aspects of nitrogen and phosphorus cycling. We found that gross protein depolymerization, N mineralization (ammonification), and nitrification rates were negatively related to litter C:N. Rates of P mineralization were negatively correlated with litter C:P. The negative correlations with litter C:N were stronger for inorganic N cycling processes than for gross protein depolymerization, indicating that the effect of resource stoichiometry on intracellular processes was stronger than on processes catalyzed by extracellular enzymes. Consistent with this, extracellular protein depolymerization was mainly limited by substrate availability and less so by the amount of protease. Strong positive correlations between the interconnected N and P pools and the respective production and consumption processes pointed to feed-forward control of microbial litter N and P cycling. A negative relationship between litter C:N and phosphatase activity (and between litter C:P and protease activity) demonstrated that microbes tended to allocate carbon and nutrients in ample supply into the production of extracellular enzymes to mine for the nutrient that is more limiting. Overall, the study demonstrated a strong effect of litter stoichiometry (C:N:P) on gross processes of microbial N and P cycling in decomposing litter; mineralization of N and P were tightly coupled to assist in maintaining cellular homeostasis of litter microbial communities.

  3. Dual-controlled release system of drugs for bone regeneration.

    Science.gov (United States)

    Kim, Yang-Hee; Tabata, Yasuhiko

    2015-11-01

    Controlled release systems have been noted to allow drugs to enhance their ability for bone regeneration. To this end, various biomaterials have been used as the release carriers of drugs, such as low-molecular-weight drugs, growth factors, and others. The drugs are released from the release carriers in a controlled fashion to maintain their actions for a long time period. Most research has been focused on the controlled release of single drugs to demonstrate the therapeutic feasibility. Controlled release of two combined drugs, so-called dual release systems, are promising and important for tissue regeneration. This is because the tissue regeneration process of bone formation is generally achieved by multiple bioactive molecules, which are produced from cells by other molecules. If two types of bioactive molecules, (i.e., drugs), are supplied in an appropriate fashion, the regeneration process of living bodies will be efficiently promoted. This review focuses on the bone regeneration induced by dual-controlled release of drugs. In this paper, various dual-controlled release systems of drugs aiming at bone regeneration are overviewed explaining the type of drugs and their release materials. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Gene expression profiles of fin regeneration in loach (Paramisgurnus dabryanu).

    Science.gov (United States)

    Li, Li; He, Jingya; Wang, Linlin; Chen, Weihua; Chang, Zhongjie

    2017-11-01

    Teleost fins can regenerate accurate position-matched structure and function after amputation. However, we still lack systematic transcriptional profiling and methodologies to understand the molecular basis of fin regeneration. After histological analysis, we established a suppression subtraction hybridization library containing 418 distinct sequences expressed differentially during the process of blastema formation and differentiation in caudal fin regeneration. Genome ontology and comparative analysis of differential distribution of our data and the reference zebrafish genome showed notable subcategories, including multi-organism processes, response to stimuli, extracellular matrix, antioxidant activity, and cell junction function. KEGG pathway analysis allowed the effective identification of relevant genes in those pathways involved in tissue morphogenesis and regeneration, including tight junction, cell adhesion molecules, mTOR and Jak-STAT signaling pathway. From relevant function subcategories and signaling pathways, 78 clones were examined for further Southern-blot hybridization. Then, 17 genes were chosen and characterized using semi-quantitative PCR. Then 4 candidate genes were identified, including F11r, Mmp9, Agr2 and one without a match to any database. After real-time quantitative PCR, the results showed obvious expression changes in different periods of caudal fin regeneration. We can assume that the 4 candidates, likely valuable genes associated with fin regeneration, deserve additional attention. Thus, our study demonstrated how to investigate the transcript profiles with an emphasis on bioinformatics intervention and how to identify potential genes related to fin regeneration processes. The results also provide a foundation or knowledge for further research into genes and molecular mechanisms of fin regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Electrochemical in situ regeneration of granular activated carbon using a three-dimensional reactor.

    Science.gov (United States)

    Sun, Hong; Liu, Zhigang; Wang, Ying; Li, Yansheng

    2013-12-01

    Electrochemical in situ regeneration of granular activated carbon (GAC) saturated with phenol was experimentally investigated using a three-dimensional electrode reactor with titanium filter electrode arrays. The feasibility of the electrochemical regeneration has been assessed by monitoring the regeneration efficiency and chemical oxygen demand (COD). The influence of the applied current, the effluent flow rate, and the effluent path of the electrochemical cell have been systematically studied. Under the optimum conditions, the regeneration efficiency of GAC could reach 94% in 2 hr, and no significant declination was observed after five-time continuous adsorption-regeneration cycles. The adsorption of organic pollutants was almost completely mineralized due to electrochemical oxidation, indicating that this regeneration process is much more potentially cost-effective for application. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  6. Phenotypic Plasticity Explains Response Patterns of European Beech (Fagus sylvatica L. Saplings to Nitrogen Fertilization and Drought Events

    Directory of Open Access Journals (Sweden)

    Christoph Dziedek

    2017-03-01

    Full Text Available Abstract: Climate and atmospheric changes affect forest ecosystems worldwide, but little is known about the interactive effects of global change drivers on tree growth. In the present study, we analyzed single and combined effects of nitrogen (N fertilization and drought events (D on the growth of European beech (Fagus sylvatica L. saplings in a greenhouse experiment. We quantified morphological and physiological responses to treatments for one‐ and two‐year‐old plants. N fertilization increased the saplings’ aboveground biomass investments, making them more susceptible to D treatments. This was reflected by the highest tissue dieback in combined N and D treatments and a significant N × D interaction for leaf δ13C signatures. Thus, atmospheric N deposition can strengthen the drought sensitivity of beech saplings. One‐year‐old plants reacted more sensitively to D treatments than two‐year‐old plants (indicated by D‐induced shifts in leaf δ13C signatures of one‐year‐old and two‐year‐old plants by +0.5‰ and −0.2‰, respectively, attributable to their higher shoot:root‐ratios (1.8 and 1.2, respectively. In summary, the saplings’ treatment responses were determined by their phenotypic plasticity (shifts in shoot:root‐ratios, which in turn was a function of both the saplings’ age (effects of allometric growth trajectories = apparent plasticity and environmental impacts (effects of N fertilization = plastic allometry.

  7. Improvement characteristics shown in holistic regeneration of Ballymun toward sustainable community

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yeunsook; Lim, Soohyun; Kim, Gunhyoung [Department of Housing and Interior Design, Yonsei University, Seoul (Korea)

    2010-02-15

    Substantial numbers of urban and residential environments constructed in the 20th century are experiencing degeneration and the importance of challenging to revitalize community holistically is getting more seriously recognized. There, however, has been limitation in grasping the holistic regeneration information as urban regeneration usually goes through a long-term and complicated procedure. Yet, the urban and housing regeneration's direction is required to be holistic in the 21st Century. Any precedent case that had tried the holistic regeneration needs to be checked thoroughly and thereby the result needs to be applied to the future attempts as a reference and knowledge base. The purpose of this study was to delineate improvement characteristics that appeared during the course of holistic regeneration in Ballymun of Ireland. This research is an archival research in nature which also used content analysis technique since it deals with reports and newsletters as archival records that were accumulated on a regular base throughout the whole process. The leading projects continued over ten years of improvement were scrutinized in the perspective of physical, social, economic, cultural, and environmental dimensions of regeneration. The main results were, first, a series of improvement activities and projects to regenerate each of five dimensions were delineated for comprehensive understanding. Second, connected patterns for synergistic improvement were identified and patterns were described to show the detailed contents as examples. This study would provide communities that face holistic regeneration, an insight, planning skills, creative and realistic ideas for implementation, thereby empowers planning capability toward holistic regeneration. (author)

  8. [Guided bone regeneration: general survey].

    Science.gov (United States)

    Cosyn, Jan; De Bruyn, Hugo

    2009-01-01

    The principle of 'guided bone regeneration' was first described in 1988 on the basis of animal-experimental data. Six weeks after transmandibular defects had been created and protected by non-resorbable teflonmembranes, complete bone regeneration was found. The technique was based on the selective repopulation of the wound: every infiltration of cells outside the neighbouring bone tissue was prevented by the application of the membrane. Additional animal experiments showed that guided bone regeneration was a viable treatment option for local bone defects surrounding dental implants. Clinical practice, however, showed that premature membrane exposure was a common complication, which was responsible for a tremendous reduction in regenerated bone volume. In addition, a second surgical intervention was always necessary to remove the membrane. As a result, resorbable alternatives were developed. Since these are less rigid, bone fillers are usually used simultaneously. These comprise autogenous bone chips and bone substitutes from allogenic or xenogenic origine. Also alloplastic materials could be used for this purpose. Based on their characteristics this article provides an overview of the biomaterials that could be considered for guided bone regeneration. Specific attention goes to their application in clinical practice.

  9. Harnessing biomechanics to develop cartilage regeneration strategies.

    Science.gov (United States)

    Athanasiou, Kyriacos A; Responte, Donald J; Brown, Wendy E; Hu, Jerry C

    2015-02-01

    chondrogenic cells. The challenging problem of enhanced integration of engineered cartilage with native cartilage is approached with both familiar and novel methods, such as lysyl oxidase (LOX). These diverse tissue engineering strategies all aim to build upon thorough biomechanical characterizations to produce functional neotissue that ultimately will help combat the pressing problem of cartilage degeneration. As our prior research is reviewed, we look to establish new pathways to comprehensively and effectively address the complex problems of musculoskeletal cartilage regeneration.

  10. Carbon flux to woody tissues in a beech/spruce forest during summer and in response to chronic O3 exposure

    Science.gov (United States)

    The present study compares the dynamics in carbon (C) allocation of adult deciduous beech (Fagus sylvatica) and evergreen spruce (Picea abies) during summer and in response to seven-year-long exposure with twice-ambient ozone (O3) concentrations (2 × O3). Focus was on the respira...

  11. Beech-mast crop evaluation in Kněhyně forest complex (Beskydy Mts. Czech Republic) as a food supply for granivorous rodents

    Czech Academy of Sciences Publication Activity Database

    Heroldová, Marta; Suchomel, J.; Purchart, L.; Čepelka, L.

    2013-01-01

    Roč. 6, č. 1 (2013), s. 27-32 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional support: RVO:68081766 Keywords : beech mountain forests * biomass of beechnuts harvest * diet supply for granivorous species Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection

  12. Lignin properties in topsoils of a beech/oak forest after 8 years of manipulated litter fall: relevance of altered input and oxidation of lignin

    NARCIS (Netherlands)

    Klotzbücher, T.; Strohmeier, S.; Kaiser, K.; Bowden, R.D.; Lajtha, K.; Ohm, H.; Kalbitz, K.

    2013-01-01

    Background and aims We studied the response of lignin oxidation in soils of a beech/oak forest to changes in litter fall. Additionally we considered possible factors in lignin oxidation, including altered (i) input of fresh organic matter and (ii) fungi-to-bacteria ratios. Methods The field-based

  13. Modelling exploratio of the future of European beech (Fagus sylvatica L.) under climate change - Range, abundance, genetic diversity and adaptive response

    NARCIS (Netherlands)

    Kramer, K.; Degen, B.; Buschbom, J.; Hickler, T.; Thuiller, W.; Sykes, M.T.; Winter, de W.P.

    2010-01-01

    We explored impacts of climate change on the geographic distribution of European beech by applying state of the art statistical and process-based models, and assessed possible climate change impacts on both adaptive capacity in the centre of its distribution and adaptive responses of functional

  14. A new approach in the monitoring of the phytosanitary conditions of forests: the case of oak and beech stands in the Sicilian Regional Parks

    Directory of Open Access Journals (Sweden)

    Cinzia Rizza

    2016-10-01

    Full Text Available The objective of this study was to investigate the health conditions of oak and beech stands in the three Regional Parks of Sicily (Etna, Madonie and Nebrodi. A total of 81 sampling areas were investigated, 54 in oak stands and 27 in beech stands. The phytosanitary conditions of each tree within the respective sampling area was expressed with a synthetic index namely phytosanitary class (PC. Oak stands showed severe symptoms of decline, with 85% of the sampling areas including symptomatic trees. In general, beech stands were in better condition, with the exception of Nebrodi Park, where trees showed severe symptoms of decline. On oak trees, infections of fungal pathogens were also observed, including Biscogniauxia mediterranea, Polyporus sp., Fistulina hepatica, Mycrosphaera alphitoides and Armillaria sp. By contrast, on beech trees Biscogniauxia nummularia, Fomes fomentarius and Neonectria radicicola were recognized. Furthermore, twenty-two permanent sampling areas were delimited with the aim of monitoring regularly the health conditions of forests in these three parks.

  15. Effects of litter quality and parent material on organic matter characteristics and N-dynamics in Luxembourg beech and hornbeam forests

    NARCIS (Netherlands)

    Kooijman, A.M.; Martinez-Hernandez, G.B.

    2009-01-01

    To test effects of litter quality and soil conditions on N-dynamics, we selected seven forests in Luxembourg dominated by beech (Fagus sylvatica, L.) and hornbeam (Carpinus betulus L.), and located on acid loam, decalcified marl or limestone, and measured organic matter characteristics, microbial C

  16. Peptidomics Analysis of Transient Regeneration in the Neonatal Mouse Heart.

    Science.gov (United States)

    Fan, Yi; Zhang, Qijun; Li, Hua; Cheng, Zijie; Li, Xing; Chen, Yumei; Shen, Yahui; Wang, Liansheng; Song, Guixian; Qian, Lingmei

    2017-09-01

    Neonatal mouse hearts have completely regenerative capability after birth, but the ability to regenerate rapidly lost after 7 days, the mechanism has not been clarified. Previous studies have shown that mRNA profile of adult mouse changed greatly compared to neonatal mouse. So far, there is no research of peptidomics related to heart regeneration. In order to explore the changes of proteins, enzymes, and peptides related to the transient regeneration, we used comparative petidomics technique to compare the endogenous peptides in the mouse heart of postnatal 1 and 7 days. In final, we identified 236 differentially expressed peptides, 169 of which were upregulated and 67 were downregulated in the postnatal 1 day heart, and also predicted 36 functional peptides associated with transient regeneration. The predicted 36 candidate peptides are located in the important domains of precursor proteins and/or contain the post-transcriptional modification (PTM) sites, which are involved in the biological processes of cardiac development, cardiac muscle disease, cell proliferation, necrosis, and apoptosis. In conclusion, for the first time, we compared the peptidomics profiles of neonatal heart between postnatal 1 day and postnatal 7 day. This study provides a new direction and an important basis for the mechanism research of transient regeneration in neonatal heart. J. Cell. Biochem. 118: 2828-2840, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. The Hardwood Tree Improvement and Regeneration Center: its strategic plans for sustaining the hardwood resource

    Science.gov (United States)

    Charles H. Michler; Michael J. Bosela; Paula M. Pijut; Keith E. Woeste

    2003-01-01

    A regional center for hardwood tree improvement, genomics, and regeneration research, development and technology transfer will focus on black walnut, black cherry, northern red oak and, in the future, on other fine hardwoods as the effort is expanded. The Hardwood Tree Improvement and Regeneration Center (HTIRC) will use molecular genetics and genomics along with...

  18. Biotechnology in the Treatment of Sensorineural Hearing Loss: Foundations and Future of Hair Cell Regeneration

    Science.gov (United States)

    Parker, Mark A.

    2011-01-01

    Purpose: To provide an overview of the methodologies involved in the field of hair cell regeneration. First, the author provides a tutorial on the biotechnological foundations of this field to assist the reader in the comprehension and interpretation of the research involved in hair cell regeneration. Next, the author presents a review of stem…

  19. Microwave regeneration of molecular sieves

    International Nuclear Information System (INIS)

    Singh, V.P.

    1984-05-01

    Molecular sieve driers have been included in the design of tritium handling systems for fusion reactors. In these systems there is a need to maintain extremely low exit dew points from the driers as well as a capability to rapidly reduce tritium concentrations following an accident. The required capacity of the driers is very high. The conventional method of regenerating these sieves after a water adsorption cycle is with hot air. However, because water is rapidly heated by microwave energy, this technology may be suitable for decreasing the bed regeneration time and hence may allow reduced capital and operating costs associated with a smaller bed. The present study was conducted to obtain preliminary information on the technical feasibility of regenerating molecular sieves with microwave energy. The study concentrated on Type 4A molecular sieve with a few tests on Type 13X sieve and also a silica gel adsorbent

  20. Regenerator cross arm seal assembly

    Science.gov (United States)

    Jackman, Anthony V.

    1988-01-01

    A seal assembly for disposition between a cross arm on a gas turbine engine block and a regenerator disc, the seal assembly including a platform coextensive with the cross arm, a seal and wear layer sealingly and slidingly engaging the regenerator disc, a porous and compliant support layer between the platform and the seal and wear layer porous enough to permit flow of cooling air therethrough and compliant to accommodate relative thermal growth and distortion, a dike between the seal and wear layer and the platform for preventing cross flow through the support layer between engine exhaust and pressurized air passages, and air diversion passages for directing unregenerated pressurized air through the support layer to cool the seal and wear layer and then back into the flow of regenerated pressurized air.

  1. Piezoelectric materials for tissue regeneration: A review.

    Science.gov (United States)

    Rajabi, Amir Hossein; Jaffe, Michael; Arinzeh, Treena Livingston

    2015-09-01

    The discovery of piezoelectricity, endogenous electric fields and transmembrane potentials in biological tissues raised the question whether or not electric fields play an important role in cell function. It has kindled research and the development of technologies in emulating biological electricity for tissue regeneration. Promising effects of electrical stimulation on cell growth and differentiation and tissue growth has led to interest in using piezoelectric scaffolds for tissue repair. Piezoelectric materials can generate electrical activity when deformed. Hence, an external source to apply electrical stimulation or implantation of electrodes is not needed. Various piezoelectric materials have been employed for different tissue repair applications, particularly in bone repair, where charges induced by mechanical stress can enhance bone formation; and in neural tissue engineering, in which electric pulses can stimulate neurite directional outgrowth to fill gaps in nervous tissue injuries. In this review, a summary of piezoelectricity in different biological tissues, mechanisms through which electrical stimulation may affect cellular response, and recent advances in the fabrication and application of piezoelectric scaffolds will be discussed. The discovery of piezoelectricity, endogenous electric fields and transmembrane potentials in biological tissues has kindled research and the development of technologies using electrical stimulation for tissue regeneration. Piezoelectric materials generate electrical activity in response to deformations and allow for the delivery of an electrical stimulus without the need for an external power source. As a scaffold for tissue engineering, growing interest exists due to its potential of providing electrical stimulation to cells to promote tissue formation. In this review, we cover the discovery of piezoelectricity in biological tissues, its connection to streaming potentials, biological response to electrical stimulation and

  2. Natural regeneration processes in big sagebrush (Artemisia tridentata)

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified and characterized the controls of big sagebrush seed production, germination, and establishment. The largest knowledge gaps and associated research needs include quiescence and dormancy of embryos and seedlings; variation in seed production and germination percentages; wet-thermal time model of germination; responses to frost events (including freezing/thawing of soils), CO2 concentration, and nutrients in combination with water availability; suitability of microsite vs. site conditions; competitive ability as well as seedling growth responses; and differences among subspecies and ecoregions. Potential impacts of climate change on big sagebrush regeneration could include that temperature increases may not have a large direct influence on regeneration due to the broad temperature optimum for regeneration, whereas indirect effects could include selection for populations with less stringent seed dormancy. Drier conditions will have direct negative effects on germination and seedling survival and could also lead to lighter seeds, which lowers germination success further. The short seed dispersal distance of big sagebrush may limit its tracking of suitable climate; whereas, the low competitive ability of big sagebrush seedlings may limit successful competition with species that track climate. An improved understanding of the

  3. "We Was Regenerated Out": Regeneration, Recycling and Devaluing Communities

    Directory of Open Access Journals (Sweden)

    Luna Glucksberg

    2014-12-01

    Full Text Available This article looks at well documented processes of urban regeneration and community displacement in the inner-city through an innovative anthropological perspective focused on concepts of waste and value. Using the notion of symbolic devaluation of the working classes developed by Skeggs (1997; 2004, it traces their exclusion from recycling practices while at the same time the estates they live on are being regenerated. Raising questions about the parallels and contradictions between regeneration and recycling, it shows how symbolic devaluation of specifi c areas and their inhabitants are necessary precursors of the physical demolition and removal that characterize regeneration processes. Through an ethnographic approach, the deep connections between people and their waste, and people as waste, are exposed and questioned, showing how valuable middle class selves are produced through appropriate waste management procedures, i.e. individualized recycling, while inner-city, estate dwellers are remade into uncaring, unworthy citizens who cannot take part in this value-producing circuit.

  4. Plant Regeneration and Genetic Transformation in Eggplant ...

    African Journals Online (AJOL)

    Dr Harmander Gill

    2014-02-05

    Feb 5, 2014 ... Review. Plant regeneration in eggplant (Solanum melongena L.): A review ... and development of somatic hybrids, efficient plant regeneration ... was first reported in eggplant from immature seed embryos .... Hormone free MS.

  5. Climate change induces shifts in abundance and activity pattern of bacteria and archaea catalyzing major transformation steps in nitrogen turnover in a soil from a mid-European beech forest.

    Science.gov (United States)

    Gschwendtner, Silvia; Tejedor, Javier; Bimüller, Carolin; Bimueller, Carolin; Dannenmann, Michael; Kögel-Knabner, Ingrid; Knabner, Ingrid Kögel; Schloter, Michael

    2014-01-01

    Ongoing climate change will lead to more extreme weather events, including severe drought periods and intense drying rewetting cycles. This will directly influence microbial nitrogen (N) turnover rates in soil by changing the water content and the oxygen partial pressure. Therefore, a space for time climate change experiment was conducted by transferring intact beech seedling-soil mesocosms from a northwest (NW) exposed site, representing today's climatic conditions, to a southwest (SW) exposed site, providing a model climate for future conditions with naturally occurring increased soil temperature (+0.8°C in average). In addition, severe drought and intense rainfall was simulated by a rainout shelter at SW and manual rewetting after 39 days drought, respectively. Soil samples were taken in June, at the end of the drought period (August), 24 and 72 hours after rewetting (August) and after a regeneration period of four weeks (September). To follow dynamics of bacterial and archaeal communities involved in N turnover, abundance and activity of nitrifiers, denitrifiers, N2-fixing microbes and N-mineralizers was analyzed based on marker genes and the related transcripts by qPCR from DNA and RNA directly extracted from soil. Abundance of the transcripts was reduced under climate change with most pronounced effects for denitrification. Our results revealed that already a transfer from NW to SW without further treatment resulted in decreased cnor and nosZ transcripts, encoding for nitric oxide reductase and nitrous oxide reductase, respectively, while nirK transcripts, encoding for nitrite reductase, remained unaffected. Severe drought additionally led to reduced nirK and cnor transcripts at SW. After rewetting, nirK transcripts increased rapidly at both sites, while cnor and nosZ transcripts increased only at NW. Our data indicate that the climate change influences activity pattern of microbial communities involved in denitrification processes to a different extend

  6. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand’s southern beech treelines

    Science.gov (United States)

    Buckley, Hannah L.

    2015-01-01

    Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m) meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential of such an approach

  7. Local-scale topoclimate effects on treeline elevations: a country-wide investigation of New Zealand’s southern beech treelines

    Directory of Open Access Journals (Sweden)

    Bradley S. Case

    2015-10-01

    Full Text Available Although treeline elevations are limited globally by growing season temperature, at regional scales treelines frequently deviate below their climatic limit. The cause of these deviations relate to a host of climatic, disturbance, and geomorphic factors that operate at multiple scales. The ability to disentangle the relative effects of these factors is currently hampered by the lack of reliable topoclimatic data, which describe how regional climatic characteristics are modified by topographic effects in mountain areas. In this study we present an analysis of the combined effects of local- and regional-scale factors on southern beech treeline elevation variability at 28 study areas across New Zealand. We apply a mesoscale atmospheric model to generate local-scale (200 m meteorological data at these treelines and, from these data, we derive a set of topoclimatic indices that reflect possible detrimental and ameliorative influences on tree physiological functioning. Principal components analysis of meteorological data revealed geographic structure in how study areas were situated in multivariate space along gradients of topoclimate. Random forest and conditional inference tree modelling enabled us to tease apart the relative effects of 17 explanatory factors on local-scale treeline elevation variability. Overall, modelling explained about 50% of the variation in treeline elevation variability across the 28 study areas, with local landform and topoclimatic effects generally outweighing those from regional-scale factors across the 28 study areas. Further, the nature of the relationships between treeline elevation variability and the explanatory variables were complex, frequently non-linear, and consistent with the treeline literature. To our knowledge, this is the first study where model-generated meteorological data, and derived topoclimatic indices, have been developed and applied to explain treeline variation. Our results demonstrate the potential

  8. QPSK regeneration without active phase-locking

    DEFF Research Database (Denmark)

    Kjøller, Niels-Kristian; Da Ros, Francesco; Røge, Kasper Meldgaard

    2016-01-01

    QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal.......QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal....

  9. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0–14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ13C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ13C, both hydraulic efficiency and embolism resistance were

  10. Regeneration of the anterior cruciate ligament: Current strategies in tissue engineering

    Science.gov (United States)

    Nau, Thomas; Teuschl, Andreas

    2015-01-01

    Recent advancements in the field of musculoskeletal tissue engineering have raised an increasing interest in the regeneration of the anterior cruciate ligament (ACL). It is the aim of this article to review the current research efforts and highlight promising tissue engineering strategies. The four main components of tissue engineering also apply in several ACL regeneration research efforts. Scaffolds from biological materials, biodegradable polymers and composite materials are used. The main cell sources are mesenchymal stem cells and ACL fibroblasts. In addition, growth factors and mechanical stimuli are applied. So far, the regenerated ACL constructs have been tested in a few animal studies and the results are encouraging. The different strategies, from in vitro ACL regeneration in bioreactor systems to bio-enhanced repair and regeneration, are under constant development. We expect considerable progress in the near future that will result in a realistic option for ACL surgery soon. PMID:25621217

  11. Guide to Regeneration of Bottomland Hardwoods

    Science.gov (United States)

    Martha R. McKevlin

    1992-01-01

    This guide will help landowners, consulting foresters, and public service foresters regenerate bottomland hardwoods. It discusses (1) interpretation of site characteristics, (2) selection of species, and (3) selection of regeneration methods. A dichotomous key for selection of appropriate regeneration methods under various conditions is presented.

  12. All optical regeneration using semiconductor devices

    DEFF Research Database (Denmark)

    Mørk, Jesper; Öhman, Filip; Tromborg, Bjarne

    All-optical regeneration is a key functionality for implementing all-optical networks. We present a simple theory for the bit-error-rate in links employing all-optical regenerators, which elucidates the interplay between the noise and and nonlinearity of the regenerator. A novel device structure ...... is analyzed, emphasizing general aspects of active semiconductor waveguides....

  13. Semiconductor devices for all-optical regeneration

    DEFF Research Database (Denmark)

    Öhman, Filip; Bischoff, Svend; Tromborg, Bjarne

    2003-01-01

    We review different implementations of semiconductor devices for all-optical regeneration. A general model will be presented for all-optical regeneration in fiber links, taking into consideration the trade-off between non-linearity and noise. Furthermore we discuss a novel regenerator type, based...

  14. Sensory hair cell regeneration in the zebrafish lateral line.

    Science.gov (United States)

    Lush, Mark E; Piotrowski, Tatjana

    2014-10-01

    Damage or destruction of sensory hair cells in the inner ear leads to hearing or balance deficits that can be debilitating, especially in older adults. Unfortunately, the damage is permanent, as regeneration of the inner ear sensory epithelia does not occur in mammals. Zebrafish and other non-mammalian vertebrates have the remarkable ability to regenerate sensory hair cells and understanding the molecular and cellular basis for this regenerative ability will hopefully aid us in designing therapies to induce regeneration in mammals. Zebrafish not only possess hair cells in the ear but also in the sensory lateral line system. Hair cells in both organs are functionally analogous to hair cells in the inner ear of mammals. The lateral line is a mechanosensory system found in most aquatic vertebrates that detects water motion and aids in predator avoidance, prey capture, schooling, and mating. Although hair cell regeneration occurs in both the ear and lateral line, most research to date has focused on the lateral line due to its relatively simple structure and accessibility. Here we review the recent discoveries made during the characterization of hair cell regeneration in zebrafish. Copyright © 2014 Wiley Periodicals, Inc.

  15. SENSORY HAIR CELL REGENERATION IN THE ZEBRAFISH LATERAL LINE

    Science.gov (United States)

    Lush, Mark E.; Piotrowski, Tatjana

    2014-01-01

    Damage or destruction of sensory hair cells in the inner ear leads to hearing or balance deficits that can be debilitating, especially in older adults. Unfortunately, the damage is permanent, as regeneration of the inner ear sensory epithelia does not occur in mammals. Zebrafish and other non-mammalian vertebrates have the remarkable ability to regenerate sensory hair cells and understanding the molecular and cellular basis for this regenerative ability will hopefully aid us in designing therapies to induce regeneration in mammals. Zebrafish not only possess hair cells in the ear but also in the sensory lateral line system. Hair cells in both organs are functionally analogous to hair cells in the inner ear of mammals. The lateral line is a mechanosensory system found in most aquatic vertebrates that detects water motion and aids in predator avoidance, prey capture, schooling and mating. Although hair cell regeneration occurs in both the ear and lateral line, most research to date has focused on the lateral line due to its relatively simple structure and accessibility. Here we review the recent discoveries made during the characterization of hair cell regeneration in zebrafish. PMID:25045019

  16. MECHANICAL REGENERATION OF SAND WASTE

    Directory of Open Access Journals (Sweden)

    D. I. Gnir

    2005-01-01

    Full Text Available The experimental activation of the sand regenerator of the firm SINTO is carried out at ОАО “MZOO". It is shown that sand grains are cleared from films of binding agents, that allows to use the treated sand for preparation of agglutinant and core sands.

  17. Integrating three-dimensional printing and nanotechnology for musculoskeletal regeneration

    Science.gov (United States)

    Nowicki, Margaret; Castro, Nathan J.; Rao, Raj; Plesniak, Michael; Zhang, Lijie Grace

    2017-09-01

    The field of tissue engineering is advancing steadily, partly due to advancements in rapid prototyping technology. Even with increasing focus, successful complex tissue regeneration of vascularized bone, cartilage and the osteochondral interface remains largely illusive. This review examines current three-dimensional printing techniques and their application towards bone, cartilage and osteochondral regeneration. The importance of, and benefit to, nanomaterial integration is also highlighted with recent published examples. Early-stage successes and challenges of recent studies are discussed, with an outlook to future research in the related areas.

  18. Regeneration and replacement in the vertebrate inner ear.

    Science.gov (United States)

    Matsui, Jonathan I; Parker, Mark A; Ryals, Brenda M; Cotanche, Douglas A

    2005-10-01

    Deafness affects more than 40 million people in the UK and the USA, and many more world-wide. The primary cause of hearing loss is damage to or death of the sensory receptor cells in the inner ear, the hair cells. Birds can readily regenerate their cochlear hair cells but the mammalian cochlea has shown no ability to regenerate after damage. Current research efforts are focusing on gene manipulation, gene therapy and stem cell transplantation for repairing or replacing damaged mammalian cochlear hair cells, which could lead to therapies for treating deafness in humans.

  19. Bone regeneration with biomaterials and active molecules delivery.

    Science.gov (United States)

    D' Este, Matteo; Eglin, David; Alini, Mauro; Kyllonen, Laura

    2015-01-01

    The combination of biomaterials and drug delivery strategies is a promising avenue towards improved synthetic bone substitutes. With the delivery of active species biomaterials can be provided with the bioactivity they still lack for improved bone regeneration. Recently, a lot of research efforts have been put towards this direction. Biomaterials for bone regeneration have been supplemented with small or biological molecules for improved osteoprogenitor cell recruitment, osteoinductivity, anabolic or angiogenic response, regulation of bone metabolism and others. The scope of this review is to summarize the most recent results in this field.

  20. Interactions of fungi from fermented sausage with regenerated cellulose casings

    Science.gov (United States)

    Hassan K. Sreenath; Thomas W. Jeffries

    2011-01-01

    This research examined cellulolytic effects of fungi and other microbes present in cured sausages on the strength and stability of regenerated cellulose casings (RCC) used in the sausage industry. Occasionally during the curing process, RCC would split or fail, thereby leading to loss of product. The fungus Penicillium sp. BT-F-1, which was isolated from fermented...

  1. Regenerable Air Purification System for Gas-Phase Contaminant Control

    Science.gov (United States)

    Constantinescu, Ileana C.; Finn, John E.; LeVan, M. Douglas; Lung, Bernadette (Technical Monitor)

    2000-01-01

    Tests of a pre-prototype regenerable air purification system (RAPS) that uses water vapor to displace adsorbed contaminants from an adsorbent column have been performed at NASA Ames Research Center. A unit based on this design can be used for removing trace gas-phase contaminants from spacecraft cabin air or from polluted process streams including incinerator exhaust. During the normal operation mode, contaminants are removed from the air on the column. Regeneration of the column is performed on-line. During regeneration, contaminants are displaced and destroyed inside the closed oxidation loop. In this presentation we discuss initial experimental results for the performance of RAPS in the removal and treatment of several important spacecraft contaminant species from air.

  2. Liver regeneration is dependent on the extent of hepatectomy

    DEFF Research Database (Denmark)

    Meier, Michelle; Knudsen, Anders Riegels; Andersen, Kasper Jarlhelt

    of liver tissue and blood for liver specific serology. The change in liver weight after PH was evaluated as liver regeneration rate (RR). Histological analyses of liver cell proliferation and proteomic analyses are in progress. The gain in liver weight as well as RR increased significantly with the size......The upper limit for the size of hepatectomy is approximately 90% in rats. The present research project is designed to investigate the molecular pathways leading to either liver regeneration or liver failure after extended hepatectomy. In this first study we investigated the impact of different size...... of hepatectomy on liver regeneration in a rat model. Male Wistar rats were divided into four groups: 30% (n=24), 70% (n=24) and 90% (n=24) partial hepatectomy (PH) was performed together with a SHAM group (n=24). Euthanization took place at postoperative day (POD) 1 (n=8), 3 (n=8), and 5 (n=8) with harvesting...

  3. New Trends in Heart Regeneration: A Review

    Directory of Open Access Journals (Sweden)

    Kochegarov A

    2016-11-01

    Full Text Available In this review, we focus on new approaches that could lead to the regeneration of heart muscle and the restoration of cardiac muscle function derived from newly-formed cardiomyocytes. Various strategies for the production of cardiomyocytes from embryonic stem cells, induced pluripotent stem cells, adult bone marrow stem cells and cardiac spheres from human heart biopsies are described. Pathological conditions which lead to atherosclerosis and coronary artery disease often are followed by myocardial infarction causing myocardial cell death. After cell death, there is very little self-regeneration of the cardiac muscle tissue, which is replaced by non-contractile connective tissue, thus weakening the ability of the heart muscle to contract fully and leading to heart failure. A number of experimental research approaches to stimulate heart muscle regeneration with the hope of regaining normal or near normal heart function in the damaged heart muscle have been attempted. Some of these very interesting studies have used a variety of stem cell types in combination with potential cardiogenic differentiation factors in an attempt to promote differentiation of new cardiac muscle for possible future use in the clinical treatment of patients who have suffered heart muscle damage from acute myocardial infarctions or related cardiovascular diseases. Although progress has been made in recent years relative to promoting the differentiation of cardiac muscle tissue from non-muscle cells, much work remains to be done for this technology to be used routinely in translational clinical medicine to treat patients with damaged heart muscle tissue and return such individuals to pre-heart-attack activity levels.

  4. Operations Charioteer, Musketeer, Touchstone, Cornerstone, Aqueduct, Sculpin and Julin. Tests Mill Yard, Diamond Beech, Mighty Oak, Middle Note Mission Ghost, Mission Cyber, Misty Echo, Disko Elm, Mineral Quarry, Distant Zenith, Diamond Fortune, and Hunters Trophy

    National Research Council Canada - National Science Library

    Schoengold, Carole

    1999-01-01

    ...; Tests MILL YARD, DIAMOND BEECH, MIGHTY OAK, MIDDLE NOTE, MISSION GHOST, MISSION CYBER, MISTY ECHO, DISKO ELM, MINERAL QUARRY, DISTANT ZENITH, DIAMOND FORTUNE, and HUNTERS TROPHY, 9 October 1985 to 18 September 1992...

  5. Development of a Novel Degradation-Controlled Magnesium-Based Regeneration Membrane for Future Guided Bone Regeneration (GBR Therapy

    Directory of Open Access Journals (Sweden)

    Da-Jun Lin

    2017-11-01

    Full Text Available This study aimed to develop and evaluate the ECO-friendly Mg-5Zn-0.5Zr (ECO505 alloy for application in dental-guided bone regeneration (GBR. The microstructure and surface properties of biomedical Mg materials greatly influence anti-corrosion performance and biocompatibility. Accordingly, for the purpose of microstructure and surface modification, heat treatments and surface coatings were chosen to provide varied functional characteristics. We developed and integrated both an optimized solution heat-treatment condition and surface fluoride coating technique to fabricate a Mg-based regeneration membrane. The heat-treated Mg regeneration membrane (ARRm-H380 and duplex-treated regeneration membrane group (ARRm-H380-F24 h were thoroughly investigated to characterize the mechanical properties, as well as the in vitro corrosion and in vivo degradation behaviors. Significant enhancement in ductility and corrosion resistance for the ARRm-H380 was obtained through the optimized solid-solution heat treatment; meanwhile, the corrosion resistance of ARRm-H380-F24 h showed further improvement, resulting in superior substrate integrity. In addition, the ARRm-H380 provided the proper amount of Mg-ion concentration to accelerate bone growth in the early stage (more than 80% new bone formation. From a specific biomedical application point of view, these research results point out a successful manufacturing route and suggest that the heat treatment and duplex treatment could be employed to offer custom functional regeneration membranes for different clinical patients.

  6. Relationship between particular dendrobiometrical indicators of natural European beech (Fagus sylvatica L. dendrocenoses in Central Balkan Range

    Directory of Open Access Journals (Sweden)

    Ferezliev Angel

    2017-12-01

    Full Text Available In parallel studies, different regression models were tested to identify relationships between particular dendrobiometrical indicators on two sample plots representing forests dominated by the European beech in the Central Balkan Range (Bulgaria. The presence of incomplete multicollinearity was studied through correlation matrix for factor variables. To avoid multicollinear negative impact, step multiple regression was applied and adequate regression equations of the relationships under consideration were formulated. The results of statistical analysis confirmed that the link between the investigated indicators is strong and that the ’cloud‘ data show some ’sphericity‘ and distribution close to normal. In one of the sample plots, one major volume-forming factor – height does not participate in the obtained regression equation, so it is not possible to estimate its influence. By testing linear and several nonlinear regression dependencies and by mediating widely used statistical criterions for model selection, the optimal linear model of the considered link was chosen.

  7. The Investigation on Feasibility of Oriented Strand Boards to Parquet Production from Mixed Residual Veneer Popular and Beech

    Directory of Open Access Journals (Sweden)

    Saeid Kamrani

    2013-06-01

    Full Text Available The objective of this study was to investigate of feasibility of using residual veneer (popular and beechto manufacture oriented strand board (OSB parquet. Percentage of mixed residual veneer popular to beech was 40%to 60% respectly. In this study press time (6, 8 and 10 min and press temperature (170º, 180ºwere selected as variables, other factors being kept constant. Results indicated that increase of press temperature had no significant effect on modules of rupture, modules of elasticity and hardness but had significant effect on internal bonding, water absorption and thickness swelling. However results indicated that increase of press time had significant effect on total physical and mechanical properties of boards.

  8. Optical Regeneration and Noise in Semiconductor Devices

    DEFF Research Database (Denmark)

    Öhman, Filip

    2005-01-01

    In this report all-optical 2R-regeneration in optical communication systems is investigated. A simple regenerator device based on concatenated semiconductor optical amplifiers (SOAs) and electro absorbers (EAs) is introduced and examined. Experiments show that the monolithic SOA-EA 2R-regenerator......In this report all-optical 2R-regeneration in optical communication systems is investigated. A simple regenerator device based on concatenated semiconductor optical amplifiers (SOAs) and electro absorbers (EAs) is introduced and examined. Experiments show that the monolithic SOA-EA 2R...

  9. Distribution model of understory vegetation in beech forests from Central Apennines (Italy in relation to edaphic parameters

    Directory of Open Access Journals (Sweden)

    De Nicola C

    2007-12-01

    Full Text Available The first results of a study of monitoring species and habitats in the framework of the Life 04NAT/IT/000190 "Tutela dei siti Natura 2000 gestiti dal Corpo Forestale dello Stato" are presented. This study was carried out by the Department of Plant Biology of the University of Rome (La Sapienza and the National Forest Service. We focused the investigation on the relationships between herbaceous species and pedological parameters (humus and soil in Central-Apennine beech forests. Data have been collected through 40 phytosociological relevés, 15 soil profiles and 40 humus profiles in 40 forest plots, between March 2005 and September 2006. In this paper we presented data elaborated on a subset of 15 plots where soil profiles were available. The species of undergrowth showed different ecological requirements to some edaphic and humus parameters (pH, sand, loam, clay, organic matter, nitrogen, carbon/nitrogen ratio, Ca++, K+;thickness and carbon content of the organic layers: significant correlations have been found using Pearson correlation test. The multiple regression analysis allowed to identify the factors more influencing the species distribution: thickness of the organic layers, carbon content (% C and carbon/nitrogen ratio (C/N. Basing on the thickness of humus horizons (OL, OF, OH, and on carbon content, two species groups with different ecology have been recognized: (a nemoral species typical of shady beech stands on oligomull/dysmull/thin amphimull (0 < 1cm.; 5.7 < %C < 9.9; (b heliophilous species of more xeric stands on thick amphimull (1.25 < 11.5 cm.; 9.9 < %C < 13.7. The relationships among species and soil parameters and humus forms allow to recognize small differences within a homogeneous habitat and therefore they can provide management indications also at micro-scale level.

  10. Nerves Regulate Cardiomyocyte Proliferation and Heart Regeneration.

    Science.gov (United States)

    Mahmoud, Ahmed I; O'Meara, Caitlin C; Gemberling, Matthew; Zhao, Long; Bryant, Donald M; Zheng, Ruimao; Gannon, Joseph B; Cai, Lei; Choi, Wen-Yee; Egnaczyk, Gregory F; Burns, Caroline E; Burns, C Geoffrey; MacRae, Calum A; Poss, Kenneth D; Lee, Richard T

    2015-08-24

    Some organisms, such as adult zebrafish and newborn mice, have the capacity to regenerate heart tissue following injury. Unraveling the mechanisms of heart regeneration is fundamental to understanding why regeneration fails in adult humans. Numerous studies have revealed that nerves are crucial for organ regeneration, thus we aimed to determine whether nerves guide heart regeneration. Here, we show using transgenic zebrafish that inhibition of cardiac innervation leads to reduction of myocyte proliferation following injury. Specifically, pharmacological inhibition of cholinergic nerve function reduces cardiomyocyte proliferation in the injured hearts of both zebrafish and neonatal mice. Direct mechanical denervation impairs heart regeneration in neonatal mice, which was rescued by the administration of neuregulin 1 (NRG1) and nerve growth factor (NGF) recombinant proteins. Transcriptional analysis of mechanically denervated hearts revealed a blunted inflammatory and immune response following injury. These findings demonstrate that nerve function is required for both zebrafish and mouse heart regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. 24.000 ha de păduri primare de fag, propunerea României pentru Patrimoniul Mondial UNESCO [24000 ha of primary beech forests, the Romanian proposal in UNESCO World Heritage

    Directory of Open Access Journals (Sweden)

    Biriș I.-A.

    2016-08-01

    Full Text Available Under the coordination of The Ministry of Environment, Waters and Forests, about 24000 ha of primeval beech forests located in 8 natural protected area from the Romanian Carpathians were included for inscription into the World Heritage List to extend the „Primeval Beech Forests of the Carpathians and the Ancient Beech Forests of Germany” (1133bis. The extended World Heritage property is proposed to carry the joint new name: „Primeval Beech Forests of the Carpathians and Other Regions of Europe”. Supported by 13 European countries (Romania included, the nomination proposes to establish a transnational serial UNESCO property, with a surface of more that 95000 ha, that reunites the most representative and well preserved beech forests from the natural areal of this species in order to illustrate the ecological process of extension - that is in progress at present - of beech on the European continent. The process of choosing these canditate sites was thought for completing the existent sites and for providing arguments and reflecting better on the extension of species distribution at the level of Europe. At the end of January 2016, Austria, the coordinator country of the nomination process at the international level transmitted the common dossier for the nomination to the committee of evaluation of UNESCO World Heritage List.

  12. Nanostructured Mesoporous Silicas for Bone Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Isabel Izquierdo-Barba

    2008-01-01

    Full Text Available The research on the development of new biomaterials that promote bone tissue regeneration is receiving great interest by the biomedical scientific community. Recent advances in nanotechnology have allowed the design of materials with nanostructure similar to that of natural bone. These materials can promote new bone formation by inducing the formation of nanocrystalline apatites analogous to the mineral phase of natural bone onto their surfaces, i.e. they are bioactive. They also stimulate osteoblast proliferation and differentiation and, therefore, accelerate the healing processes. Silica-based ordered mesoporous materials are excellent candidates to be used as third generation bioceramics that enable the adsorption and local control release of biological active agents that promote bone regeneration. This local delivery capability together with the bioactive behavior of mesoporous silicas opens up promising expectations in the bioclinical field. In this review, the last advances in nanochemistry aimed at designing and tailoring the chemical and textural properties of mesoporous silicas for biomedical applications are described. The recent developed strategies to synthesize bioactive glasses with ordered mesopore arrangements are also summarized. Finally, a deep discussion about the influence of the textural parameters and organic modification of mesoporous silicas on molecules adsorption and controlled release is performed.

  13. Innovative Approaches to Regenerate Enamel and Dentin

    Directory of Open Access Journals (Sweden)

    Xanthippi Chatzistavrou

    2012-01-01

    Full Text Available The process of tooth mineralization and the role of molecular control of cellular behavior during embryonic tooth development have attracted much attention the last few years. The knowledge gained from the research in these fields has improved the general understanding about the formation of dental tissues and the entire tooth and set the basis for teeth regeneration. Tissue engineering using scaffold and cell aggregate methods has been considered to produce bioengineered dental tissues, while dental stem/progenitor cells, which can differentiate into dental cell lineages, have been also introduced into the field of tooth mineralization and regeneration. Some of the main strategies for making enamel, dentin, and complex tooth-like structures are presented in this paper. However, there are still significant barriers that obstruct such strategies to move into the regular clinic practice, and these should be overcome in order to have the regenerative dentistry as the important mean that can treat the consequences of tooth-related diseases.

  14. Plantlet regeneration potential from seedling explants of vitegnus (Vitex agnus castus).

    Science.gov (United States)

    Chamandoosti, F

    2007-11-15

    In this research a simple and repeatable method for regeneration of a important medicinal plant (Vitex agnus castus) described. Different seedling explants such as hypocotyl, cotyledon, root and apical meristem were cultured in MS basal media with different kinds and concentrations of PGRs. Root and apical meristem explants were the only explants that have regeneration whole plantlets potential. It was interesting that regeneration whole plantlets from root and apical meristem explants have different developmental pathways. Whole plantlets from apical meristem explants regenerated by passing phase callusing whereas regeneration whole plantlets from root was direct and without phase callusing. This subject implies that we can have many manipulation possibilities in order to different objects of tissue culture by selecting different explants in vitegnus.

  15. The effect of hypergravity on the lens, cornea and tail regeneration in Urodela

    Science.gov (United States)

    Grigoryan, E. N.; Dvorochkin, N.; Poplinskaya, V. A.; Yousuf, R.; Radugina, E. A.; Almeida, E. A.

    2017-09-01

    In previous experiments onboard Russian Bion/Foton satellites it was found that exposure to microgravity causes changes in eye lens regeneration of Urodela. The changes included higher rate of regeneration, increased cell proliferation in lens anlage, and synchronization of lens restoration. Similar changes were observed regarding tail regeneration. Recently, investigations were performed to find out whether exposure to hypergravity could also alter lens, cornea and tail regeneration in the newt P. waltl. Nine days prior to exposure the left lens was surgically removed through corneal incision and distal 1/3 of the tail was amputated, thus initiating regeneration. The experimental animals were allowed to recover for 9 days at 1 g and then exposed to 2 g for 12 days in an 8 ft diameter centrifuge at NASA Ames Research Center. The experimental animals were divided into 1 g controls, 2 g centrifugation animals, basal controls, and aquarium controls. Lens and corneal regeneration appeared to be inhibited in 2 g group compared to 1 g animals. In all 1 g controls, lens regeneration reached stages VII-IX in a synchronous fashion and corneal regeneration was nearly complete. In the 2 g newts, neural retinal detachment from the pigmented epithelium was seen in most operated eyes. It was also observed in the non-operated (right) eyes of the animals exposed to 2 g. The level of retinal detachment varied and could have been caused by hypergravity-induced high intraocular pressure. Regeneration (when it could be assessed) proceeded asynchronously, reaching stages from II to IX. Corneal restoration was also noticeably delayed and corneal morphology changed. Cell proliferation was measured using BrdU; the results were not comparable to the 1 g data because of retinal detachment. Previous investigations demonstrated that lens regeneration was controlled by the neural retina; therefore, lower regeneration rate at 2 g was, at least in part, associated with retinal detachment. FGF2

  16. Myocardial regeneration potential of adipose tissue-derived stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Xiaowen, E-mail: baixw01@yahoo.com [Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe, Houston, TX 77030 (United States); Alt, Eckhard, E-mail: ealt@mdanderson.org [Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe, Houston, TX 77030 (United States)

    2010-10-22

    Research highlights: {yields} Various tissue resident stem cells are receiving tremendous attention from basic scientists and clinicians and hold great promise for myocardial regeneration. {yields} For practical reasons, human adipose tissue-derived stem cells are attractive stem cells for future clinical application in repairing damaged myocardium. {yields} This review summarizes the characteristics of cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential and the, underlying mechanisms, and safety issues. -- Abstract: Various tissue resident stem cells are receiving attention from basic scientists and clinicians as they hold promise for myocardial regeneration. For practical reasons, adipose tissue-derived stem cells (ASCs) are attractive cells for clinical application in repairing damaged myocardium based on the following advantages: abundant adipose tissue in most patients and easy accessibility with minimally invasive lipoaspiration procedure. Several recent studies have demonstrated that both cultured and freshly isolated ASCs could improve cardiac function in animal model of myocardial infarction. The mechanisms underlying the beneficial effect of ASCs on myocardial regeneration are not fully understood. Growing evidence indicates that transplantation of ASCs improve cardiac function via the differentiation into cardiomyocytes and vascular cells, and through paracrine pathways. Paracrine factors secreted by injected ASCs enhance angiogenesis, reduce cell apoptosis rates, and promote neuron sprouts in damaged myocardium. In addition, Injection of ASCs increases electrical stability of the injured heart. Furthermore, there are no reported cases of arrhythmia or tumorigenesis in any studies regarding myocardial regeneration with ASCs. This review summarizes the characteristics of both cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential, and the

  17. Biosensor Regeneration: A Review of Common Techniques and Outcomes.

    Science.gov (United States)

    Goode, J A; Rushworth, J V H; Millner, P A

    2015-06-16

    Biosensors are ideally portable, low-cost tools for the rapid detection of pathogens, proteins, and other analytes. The global biosensor market is currently worth over 10 billion dollars annually and is a burgeoning field of interdisciplinary research that is hailed as a potential revolution in consumer, healthcare, and industrial testing. A key barrier to the widespread adoption of biosensors, however, is their cost. Although many systems have been validated in the laboratory setting and biosensors for a range of analytes are proven at the concept level, many have yet to make a strong commercial case for their acceptance. Though it is true with the development of cheaper electrodes, circuits, and components that there is a downward pressure on costs, there is also an emerging trend toward the development of multianalyte biosensors that is pushing in the other direction. One way to reduce the cost that is suitable for certain systems is to enable their reuse, thus reducing the cost per test. Regenerating biosensors is a technique that can often be used in conjunction with existing systems in order to reduce costs and accelerate the commercialization process. This article discusses the merits and drawbacks of regeneration schemes that have been proven in various biosensor systems and indicates parameters for successful regeneration based on a systematic review of the literature. It also outlines some of the difficulties encountered when considering the role of regeneration at the point of use. A brief meta-analysis has been included in this review to develop a working definition for biosensor regeneration, and using this analysis only ∼60% of the reported studies analyzed were deemed a success. This highlights the variation within the field and the need to normalize regeneration as a standard process across the field by establishing a consensus term.

  18. Myocardial regeneration potential of adipose tissue-derived stem cells

    International Nuclear Information System (INIS)

    Bai, Xiaowen; Alt, Eckhard

    2010-01-01

    Research highlights: → Various tissue resident stem cells are receiving tremendous attention from basic scientists and clinicians and hold great promise for myocardial regeneration. → For practical reasons, human adipose tissue-derived stem cells are attractive stem cells for future clinical application in repairing damaged myocardium. → This review summarizes the characteristics of cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential and the, underlying mechanisms, and safety issues. -- Abstract: Various tissue resident stem cells are receiving attention from basic scientists and clinicians as they hold promise for myocardial regeneration. For practical reasons, adipose tissue-derived stem cells (ASCs) are attractive cells for clinical application in repairing damaged myocardium based on the following advantages: abundant adipose tissue in most patients and easy accessibility with minimally invasive lipoaspiration procedure. Several recent studies have demonstrated that both cultured and freshly isolated ASCs could improve cardiac function in animal model of myocardial infarction. The mechanisms underlying the beneficial effect of ASCs on myocardial regeneration are not fully understood. Growing evidence indicates that transplantation of ASCs improve cardiac function via the differentiation into cardiomyocytes and vascular cells, and through paracrine pathways. Paracrine factors secreted by injected ASCs enhance angiogenesis, reduce cell apoptosis rates, and promote neuron sprouts in damaged myocardium. In addition, Injection of ASCs increases electrical stability of the injured heart. Furthermore, there are no reported cases of arrhythmia or tumorigenesis in any studies regarding myocardial regeneration with ASCs. This review summarizes the characteristics of both cultured and freshly isolated stem cells obtained from adipose tissue, their myocardial regeneration potential, and the underlying

  19. Studying Planarian Regeneration Aboard the International Space Station within the Student Space Flight Experimental Program

    Science.gov (United States)

    Vista SSEP Mission 11 Team; Hagstrom, Danielle; Bartee, Christine; Collins, Eva-Maria S.

    2018-05-01

    The growing possibilities of space travel are quickly moving from science fiction to reality. However, to realize the dream of long-term space travel, we must understand how these conditions affect biological and physiological processes. Planarians are master regenerators, famous for their ability to regenerate from very small parts of the original animal. Understanding how this self-repair works may inspire regenerative therapies in humans. Two studies conducted aboard the International Space Station (ISS) showed that planarian regeneration is possible in microgravity. One study reported no regenerative defects, whereas the other study reported behavioral and microbiome alterations post-space travel and found that 1 of 15 planarians regenerated a Janus head, suggesting that microgravity exposure may not be without consequences. Given the limited number of studies and specimens, further microgravity experiments are necessary to evaluate the effects of microgravity on planarian regeneration. Such studies, however, are generally difficult and expensive to conduct. We were fortunate to be sponsored by the Student Spaceflight Experiment Program (SSEP) to investigate how microgravity affects regeneration of the planarian species Dugesia japonica on the ISS. While we were unable to successfully study planarian regeneration within the experimental constraints of our SSEP Mission, we systematically analyzed the cause for the failed experiment, leading us to propose a modified protocol. This work thus opens the door for future experiments on the effects of microgravity on planarian regeneration on SSEP Missions as well as for more advanced experiments by professional researchers.

  20. Studying Planarian Regeneration Aboard the International Space Station Within the Student Space Flight Experimental Program

    Directory of Open Access Journals (Sweden)

    Vista SSEP Mission 11 Team

    2018-05-01

    Full Text Available The growing possibilities of space travel are quickly moving from science fiction to reality. However, to realize the dream of long-term space travel, we must understand how these conditions affect biological and physiological processes. Planarians are master regenerators, famous for their ability to regenerate from very small parts of the original animal. Understanding how this self-repair works may inspire regenerative therapies in humans. Two studies conducted aboard the International Space Station (ISS showed that planarian regeneration is possible in microgravity. One study reported no regenerative defects, whereas the other study reported behavioral and microbiome alterations post-space travel and found that 1 of 15 planarians regenerated a Janus head, suggesting that microgravity exposure may not be without consequences. Given the limited number of studies and specimens, further microgravity experiments are necessary to evaluate the effects of microgravity on planarian regeneration. Such studies, however, are generally difficult and expensive to conduct. We were fortunate to be sponsored by the Student Spaceflight Experiment Program (SSEP to investigate how microgravity affects regeneration of the planarian species Dugesia japonica on the ISS. While we were unable to successfully study planarian regeneration within the experimental constraints of our SSEP Mission, we systematically analyzed the cause for the failed experiment, leading us to propose a modified protocol. This work thus opens the door for future experiments on the effects of microgravity on planarian regeneration on SSEP Missions as well as for more advanced experiments by professional researchers.

  1. Farnesoid X receptor, the bile acid sensing nuclear receptor, in liver regeneration

    Directory of Open Access Journals (Sweden)

    Guodong Li

    2015-03-01

    Full Text Available The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively studied in the past using the partial hepatectomy (PH model in rodents, where 2/3 PH is carried out by removing two lobes. The whole process of liver regeneration is complicated, orchestrated event involving a network of connected interactions, which still remain fully elusive. Bile acids (BAs are ligands of farnesoid X receptor (FXR, a nuclear receptor of ligand-activated transcription factor. FXR has been shown to be highly involved in liver regeneration. BAs and FXR not only interact with each other but also regulate various downstream targets independently during liver regeneration. Moreover, recent findings suggest that tissue-specific FXR also contributes to liver regeneration significantly. These novel findings suggest that FXR has much broader role than regulating BA, cholesterol, lipid and glucose metabolism. Therefore, these researches highlight FXR as an important pharmaceutical target for potential use of FXR ligands to regulate liver regeneration in clinic. This review focuses on the roles of BAs and FXR in liver regeneration and the current underlying molecular mechanisms which contribute to liver regeneration.

  2. Neurotrophic regulation of fibroblast dedifferentiation during limb skeletal regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Satoh, Akira; Cummings, Gillian M C; Bryant, Susan V; Gardiner, David M

    2010-01-15

    The ability of animals to repair tissue damage is widespread and impressive. Among tissues, the repair and remodeling of bone occurs during growth and in response to injury; however, loss of bone above a threshold amount is not regenerated, resulting in a "critical-size defect" (CSD). The development of therapies to replace or regenerate a CSD is a major focus of research in regenerative medicine and tissue engineering. Adult urodeles (salamanders) are unique in their ability to regenerate complex tissues perfectly, yet like mammals do not regenerate a CSD. We report on an experimental model for the regeneration of a CSD in the axolotl (the Excisional Regeneration Model) that allows for the identification of signals to induce fibroblast dedifferentiation and skeletal regeneration. This regenerative response is mediated in part by BMP signaling, as is the case in mammals; however, a complete regenerative response requires the induction of a population of undifferentiated, regeneration-competent cells. These cells can be induced by signaling from limb amputation to generate blastema cells that can be grafted to the wound, as well as by signaling from a nerve and a wound epithelium to induce blastema cells from fibroblasts within the wound environment. Copyright 2009 Elsevier Inc. All rights reserved.

  3. Down-regulate of Djrfc2 causes tissues hypertrophy during planarian regeneration.

    Science.gov (United States)

    Guo, Qi; Zhao, Guixia; Ni, Jiajia; Guo, Yanan; Zhang, Yizhe; Tian, Qingnan; Zhang, Shoutao

    2017-11-25

    Planarians are an ideal model organism for regeneration research due to their amazing ability to regenerate. DNA replication is crucial for genome stability. Replication factor C (RFC), which is a replication factor C-like complex and plays an important role during DNA replication in eukaryotes, has been reported as a wound response factor during planarian regeneration. However, how RFC controls regeneration in planarians by regulating DNA replication remains to be explained. Here, we used a two-dimensional electrophoresis (2-DE) proteomic approach to identify differentially expressed proteins in intact and regenerated planarians. Approximately 132 protein spots showed differences between intact and regenerative tissues. We selected 21 significantly expressed protein spots and processed them using TOF MS analysis. Finally, we cloned three of these candidate genes (Djhsp70, Djrfc2, Djfaim), focusing on the function of Djrfc2 during regeneration. We found that the distribution of Djrfc2 tends toward the wound site. RNA interference (RNAi) of Djrfc2 increases the number of dividing cells and the expression level of planarian neoblast marker genes, which may result in hyper-proliferation. Our studies use an available approach to directly study the regeneration dynamic at the protein level and provide further evidence to support a function of Djrfc2 in planarian regeneration. Copyright © 2017. Published by Elsevier Inc.

  4. MHD (Magnetohydrodynamics) recovery and regeneration

    Energy Technology Data Exchange (ETDEWEB)

    McIlroy, R. A. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Probert, P. B. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Lahoda, E. J. [Westinghouse Electric Corp., Pittsburgh, PA (United States); Swift, W. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Jackson, D. M. [Univ. of Tennessee Space Inst. (UTSI), Tullahoma, TN (United States); Prasad, J. [Univ. of Tennessee Space Inst. (UTSI), Tullahoma, TN (United States); Martin, J. [Hudson Engineering (United States); Rogers, C. [Hudson Engineering (United States); Ho, K. K. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Senary, M. K. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Lee, S. [Univ. of Akron, OH (United States)

    1988-10-01

    A two-phase program investigating MHD seed regeneration is described. In Phase I, bench scale experiments were carried out to demonstrate the technical feasibility of a proposed Seed Regeneration Process. The Phase I data has been used for the preliminary design of a Proof-of-Concept (POC) plant which will be built and tested in Phase II. The Phase I data will also be used to estimate the costs of a 300 Mw(t) demonstration plant for comparison with other processes. The Seed Regeneration Process consists of two major subprocesses; a Westinghouse Dry Reduction process and a modified Tampella (sulfur) Recovery process. The Westinghouse process reduces the recovered spent seed (i.e., potassium sulfate) to potassium polysulfide in a rotary kiln. The reduction product is dissolved in water to form green liquor, clarified to remove residual coal ash, and sent to the Tampella sulfur release system. The sulfur is released using carbon dioxide from flue gas in a two stage reaction. The sulfur is converted to elemental sulfur as a marketable by product. The potassium is crystallized from the green liquor and dried to the anhydrous form for return to the MHD unit.

  5. Transformation and regeneration of the holoparasitic plant Phelipanche aegyptiaca

    Directory of Open Access Journals (Sweden)

    Fernández-Aparicio Mónica

    2011-11-01

    Full Text Available Abstract Background Transformation and subsequent regeneration of holoparasitic plants has never been reported, in part due to challenges in developing transformation protocols, but also because regeneration of obligate parasites is difficult since their survival depends completely on successful haustorium penetration of a host and the formation of vascular connections. The recent completion of a massive transcriptome sequencing project (the Parasitic Plant Genome Project will fuel the use of genomic tools for studies on parasitic plants. A reliable system for holoparasite transformation is needed to realize the full value of this resource for reverse genetics and functional genomics studies. Results Here we demonstrate that transformation of Phelipanche aegyptiaca is achieved by infection of 3 month-old in vitro grown P. aegyptiaca calli with Agrobacterium rhizogenes harboring the yellow fluorescent protein (YFP. Four months later, YFP-positive regenerated calli were inoculated onto tomato plants growing in a minirhizotron system. Eight days after inoculation, transgenic parasite tissue formed lateral haustoria that penetrated the host and could be visualized under UV illumination through intact host root tissue. YFP-positive shoot buds were observed one month after inoculation. Conclusions This work constitutes a breakthrough in holoparasitic plant research methods. The method described here is a robust system for transformation and regeneration of a holoparasitic plant and will facilitate research on unique parasitic plant capabilities such as host plant recognition, haustorial formation, penetration and vascular connection.

  6. Predicting recovery from acid rain using the micro-spatial heterogeneity of soil columns downhill the infiltration zone of beech stemflow: introduction of a hypothesis.

    Science.gov (United States)

    Berger, Torsten W; Muras, Alexander

    Release of stored sulfur may delay the recovery of soil pH from Acid Rain. It is hypothesized that analyzing the micro-spatial heterogeneity of soil columns downhill of a beech stem enables predictions of soil recovery as a function of historic acid loads and time. We demonstrated in a very simplified approach, how these two different factors may be untangled from each other using synthetic data. Thereafter, we evaluated the stated hypothesis based upon chemical soil data with increasing distance from the stem of beech trees. It is predicted that the top soil will recover from acid deposition, as already recorded in the infiltration zone of stemflow near the base of the stem. However, in the between trees areas and especially in deeper soil horizons recovery may be highly delayed.

  7. Beech forests in the Ruhr and in the Westphalian Bight. A comparative study. Buchenwaelder im Ruhrgebiet und in der Westfaelischen Bucht. Eine vergleichende Untersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Wittig, R. (Frankfurt Univ. (Germany, F.R.). Fachbereich 16 - Biologie); Werner, W. (Trier Univ. (Germany, F.R.). Fachbereich 3 - Geographie/Geowissenschaften, Geschichte, Politikwissenschaft, Klassische Archaeologie, Aegyptologie, Kunstgeschichte, Papyrologie)

    1989-01-01

    The Ruhr district, one of the most industrialized and most densely populated regions of Germany, is part of the Westphalian Bight. The potential natural vegetation of the Ruhrgebiet are loess beech forests (Milio-Fagetum), which are also common in other parts of the Westphalian Bight. However, a comparison of the beech forests of the Ruhrgebiet with the Milio-Fagetum stands of other areas of the Westphalian Bight shows distinct differences in floristic composition of the herb layer as well as in C/N ratio and heavy metal contents of the upper 4 cm of the mineral soil. The differences can only be explained by the former long lasting immission load of the Ruhrdistrict. (orig.).

  8. Using curriculum vitae to compare some impacts of NSF research grants with research center funding

    OpenAIRE

    Monica Gaughan; Barry Bozeman

    2002-01-01

    While traditional grants remain central in US federal support of academic scientists and engineers, the role of multidisciplinary NSF Centers is growing. Little is known about how funding through these Centers affects scientific output or (as is an NSF aim) increases academic collaboration with industry. This paper tests the use of CVs to examine how Center funding affects researchers' publication rates and their obtaining industry grants. Copyright , Beech Tree Publishing.

  9. Network based transcription factor analysis of regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Cameron Jo Ann

    2011-03-01

    Full Text Available Abstract Background Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs. Results We used the human orthologs of proteins previously identified by our research team as bait to identify the transcription factor (TF pathways and networks that regulate blastema formation in amputated axolotl limbs. The five most connected factors, c-Myc, SP1, HNF4A, ESR1 and p53 regulate ~50% of the proteins in our data. Among these, c-Myc and SP1 regulate 36.2% of the proteins. c-Myc was the most highly connected TF (71 targets. Network analysis showed that TGF-β1 and fibronectin (FN lead to the activation of these TFs. We found that other TFs known to be involved in epigenetic reprogramming, such as Klf4, Oct4, and Lin28 are also connected to c-Myc and SP1. Conclusions Our study provides a systems biology approach to how different molecular entities inter-connect with each other during the formation of an accumulation blastema in regenerating axolotl limbs. This approach provides an in silico methodology to identify proteins that are not detected by experimental methods such as proteomics but are potentially important to blastema formation. We found that the TFs, c-Myc and SP1 and their target genes could potentially play a central role in limb regeneration. Systems biology has the potential to map out numerous other pathways that are crucial to blastema formation in regeneration-competent limbs, to compare these to the pathways that characterize regeneration-deficient limbs and finally, to identify stem

  10. Regeneration and health: a structured, rapid literature review.

    Science.gov (United States)

    McCartney, G; Hearty, W; Taulbut, M; Mitchell, R; Dryden, R; Collins, C

    2017-07-01

    To identify and synthesise what is known about the impacts of regeneration on health, health inequalities and their socio-economic determinants. Rapid, structured literature review. A rapid, structured approach was undertaken to identifying relevant studies involving a search of peer-reviewed literature databases, an Internet search to identify relevant grey literature, and a review of articles citing two key systematic reviews. The identified citations were screened, critically appraised according to the research design and narratively synthesised. Of the 1382 identified citations, 46 were screened as relevant to the review and included in the synthesis. Fifteen citations were reviews but most of the evidence identified or included within the reviews was of medium or low quality due to a lack of longitudinal follow-up, low response rates or attrition. The evidence base on the impacts of regeneration is generally not of high quality and is prone to bias. However, it is theorised as being an important means of addressing the socio-economic determinants of health. Housing refurbishment (generally, and for specific improvements) seems likely to lead to small improvements in health, whereas rehousing and mixed-tenure approaches have less clear impacts on health and carry risks of disruption to social networks and higher rents. Changes in the social composition of communities (gentrification) is a common outcome of regeneration and some 'partnership' approaches to regeneration have been shown to have caused difficulties within communities. The evidence base for regeneration activities is limited but they have substantial potential to contribute to improving population health. Better quality evidence is available for there being positive health impacts from housing-led regeneration programmes involving refurbishment and specific housing improvements. There is also some evidence of the potential harms of regeneration activities, including social stratification

  11. Declining atmospheric deposition of heavy metals over the last three decades is reflected in soil and foliage of 97 beech (Fagus sylvatica) stands in the Vienna Woods☆

    Science.gov (United States)

    Türtscher, Selina; Berger, Pétra; Lindebner, Leopold; Berger, Torsten W.

    2017-01-01

    Rigorous studies on long-term changes of heavy metal distribution in forest soils since the implementation of emission controls are rare. Hence, we resampled 97 old-growth beech stands in the Vienna Woods. This study exploits an extensive data set of soil (infiltration zone of stemflow and between trees area) and foliar chemistry from three decades ago. It was hypothesized that declining deposition of heavy metals is reflected in soil and foliar total contents of Pb, Cu, Zn, Ni, Mn and Fe. Mean soil contents of Pb in the stemflow area declined at the highest rate from 223 to 50 mg kg−1 within the last three decades. Soil contents of Pb and Ni decreased significantly both in the stemflow area and the between trees area down to 80–90 cm soil depth from 1984 to 2012. Top soil (0–5 cm) accumulation and simultaneous loss in the lower soil over time for the plant micro nutrients Cu and Zn are suggested to be caused by plant uptake from deep horizons. Reduced soil leaching, due to a mean soil pH (H2O) increase from 4.3 to 4.9, and increased plant cycling are put forward to explain the significant increase of total Mn contents in the infiltration zone of beech stemflow. Top soil Pb contents in the stemflow area presently exceed the critical value at which toxicity symptoms may occur at numerous sites. Mean foliar contents of all six studied heavy metals decreased within the last three decades, but plant supply with the micro nutrients Cu, Zn, Mn and Fe is still in the optimum range for beech trees. It is concluded that heavy metal pollution is not critical for the studied beech stands any longer. PMID:28709055

  12. Declining atmospheric deposition of heavy metals over the last three decades is reflected in soil and foliage of 97 beech (Fagus sylvatica) stands in the Vienna Woods.

    Science.gov (United States)

    Türtscher, Selina; Berger, Pétra; Lindebner, Leopold; Berger, Torsten W

    2017-11-01

    Rigorous studies on long-term changes of heavy metal distribution in forest soils since the implementation of emission controls are rare. Hence, we resampled 97 old-growth beech stands in the Vienna Woods. This study exploits an extensive data set of soil (infiltration zone of stemflow and between trees area) and foliar chemistry from three decades ago. It was hypothesized that declining deposition of heavy metals is reflected in soil and foliar total contents of Pb, Cu, Zn, Ni, Mn and Fe. Mean soil contents of Pb in the stemflow area declined at the highest rate from 223 to 50 mg kg -1 within the last three decades. Soil contents of Pb and Ni decreased significantly both in the stemflow area and the between trees area down to 80-90 cm soil depth from 1984 to 2012. Top soil (0-5 cm) accumulation and simultaneous loss in the lower soil over time for the plant micro nutrients Cu and Zn are suggested to be caused by plant uptake from deep horizons. Reduced soil leaching, due to a mean soil pH (H 2 O) increase from 4.3 to 4.9, and increased plant cycling are put forward to explain the significant increase of total Mn contents in the infiltration zone of beech stemflow. Top soil Pb contents in the stemflow area presently exceed the critical value at which toxicity symptoms may occur at numerous sites. Mean foliar contents of all six studied heavy metals decreased within the last three decades, but plant supply with the micro nutrients Cu, Zn, Mn and Fe is still in the optimum range for beech trees. It is concluded that heavy metal pollution is not critical for the studied beech stands any longer. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Validation of PROBA-V GEOV1 and MODIS C5 & C6 fAPAR Products in a Deciduous Beech Forest Site in Italy

    Czech Academy of Sciences Publication Activity Database

    Nestola, E.; Sanchez-Zapero, J.; Latorre, C.; Mazzenga, F.; Matteucci, G.; Calfapietra, Carlo; Camacho, F.

    2017-01-01

    Roč. 9, č. 2 (2017), č. článku 126. ISSN 2072-4292 Institutional support: RVO:86652079 Keywords : fAPAR * validation * PROBA-V GEOV1 * MODIS C5 * MODIS C6 * beech forest * up-scaling * GCOS requirements * in-situ comparison and evaluation Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.244, year: 2016

  14. Size-dependence of tree growth response to drought for Norway spruce and European beech individuals in monospecific and mixed-species stands.

    Science.gov (United States)

    Ding, H; Pretzsch, H; Schütze, G; Rötzer, T

    2017-09-01

    Climate anomalies have resulted in changing forest productivity, increasing tree mortality in Central and Southern Europe. This has resulted in more severe and frequent ecological disturbances to forest stands. This study analysed the size-dependence of growth response to drought years based on 384 tree individuals of Norway spruce [Picea abies (L.) Karst.] and European beech [Fagus sylvatica ([L.)] in Bavaria, Germany. Samples were collected in both monospecific and mixed-species stands. To quantify the growth response to drought stress, indices for basal area increment, resistance, recovery and resilience were calculated from tree ring measurements of increment cores. Linear mixed models were developed to estimate the influence of drought periods. The results show that ageing-related growth decline is significant in drought years. Drought resilience and resistance decrease significantly with growth size among Norway spruce individuals. Evidence is also provided for robustness in the resilience capacity of European beech during drought stress. Spruce benefits from species mixing with deciduous beech, with over-yielding spruce in pure stands. The importance of the influence of size-dependence within tree growth studies during disturbances is highlighted and should be considered in future studies of disturbances, including drought. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. Effects of chronic elevated ozone exposure on gas exchange responses of adult beech trees (Fagus sylvatica) as related to the within-canopy light gradient

    International Nuclear Information System (INIS)

    Kitao, Mitsutoshi; Loew, Markus; Heerdt, Christian; Grams, Thorsten E.E.; Haeberle, Karl-Heinz; Matyssek, Rainer

    2009-01-01

    The effects of elevated O 3 on photosynthetic properties in adult beech trees (Fagus sylvatica) were investigated in relation to leaf mass per area as a measure of the gradually changing, within-canopy light availability. Leaves under elevated O 3 showed decreased stomatal conductance at unchanged carboxylation capacity of Rubisco, which was consistent with enhanced δ 13 C of leaf organic matter, regardless of the light environment during growth. In parallel, increased energy demand for O 3 detoxification and repair was suggested under elevated O 3 owing to enhanced dark respiration. Only in shade-grown leaves, light-limited photosynthesis was reduced under elevated O 3 , this effect being accompanied by lowered F v /F m . These results suggest that chronic O 3 exposure primarily caused stomatal closure to adult beech trees in the field regardless of the within-canopy light gradient. However, light limitation apparently raised the O 3 sensitivity of photosynthesis and accelerated senescence in shade leaves. - Across leaf differentiation in adult beech crowns, elevated ozone acted through stomatal closure on gas exchange although enhancing photosynthetic sensitivity of shaded leaves

  16. Comparison of leaf gas exchange and stable isotope signature of water-soluble compounds along canopy gradients of co-occurring Douglas-fir and European beech.

    Science.gov (United States)

    Bögelein, Rebekka; Hassdenteufel, Martin; Thomas, Frank M; Werner, Willy

    2012-07-01

    Combined δ(13) C and δ(18) O analyses of water-soluble leaf and twig phloem material were used to determine intrinsic water-use efficiency (iWUE) and variability of stomatal conductance at different crown positions in adult European beech (Fagus sylvatica) and Douglas-fir (Pseudotsuga menziesii) trees. Simultaneous gas exchange measurements allowed evaluation of the differences in calculating iWUE from leaf or phloem water-soluble compounds, and comparison with a semi-quantitative dual isotope model to infer variability of net photosynthesis (A(n) ) between the investigated crown positions. Estimates of iWUE from δ(13) C of leaf water-soluble organic matter (WSOM) outperformed the estimates from phloem compounds. In the beech crown, δ(13) C of leaf WSOM coincided clearly with gas exchange measurements. The relationship was not as reliable in the Douglas-fir. The differences in δ(18) O between leaf and phloem material were found to correlate with stomatal conductance. The semi-quantitative model approach was applicable for comparisons of daily average A(n) between different crown positions and trees. Intracanopy gradients were more pronounced in the beech than in the Douglas-fir, which reached higher values of iWUE at the respective positions, particularly under dry air conditions. © 2012 Blackwell Publishing Ltd.

  17. Changes in susceptibility of beech (Fagus sylvatica) seedlings towards Phytophthora citricola under the influence of elevated atmospheric CO{sub 2} and nitrogen fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, F., E-mail: fleischmann@wzw.tum.d [Phytopathology of Woody Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Raidl, S. [Department Biology I and GeoBioCenterLMU, Systematic Mycology, Ludwig Maximilians Universitaet Muenchen, Menzinger Strasse 67, 80638 Muenchen (Germany); Osswald, W.F. [Phytopathology of Woody Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany)

    2010-04-15

    The growth-differentiation balance hypothesis (GDBH) predicts changes in susceptibility of plants against herbivores with changing resource availability. In the presented study we tested the validity of the GDBH for trees infected with a root pathogen. For this purpose Fagus sylvatica seedlings grown under different atmospheric CO{sub 2}- and soil nitrogen regimes were infected with the root pathogen Phytophthora citricola. High nitrogen supply increased total biomass of beech regardless of the CO{sub 2}-treatment, whereas elevated CO{sub 2} enhanced biomass only in the high nitrogen treatment. The responses of beech under the different growing regimes to the Phytophthora root infection were not in line with the predictions of the GDBH. Enhanced susceptibility of beech against P. citricola was found in seedlings grown under elevated CO{sub 2} and low nitrogen supply. Fifteen months after inoculation these plants were characterized by enhanced water use efficiency, by altered root-shoot ratios, and by enhanced specific root tip densities. - Susceptibility of Fagus sylvatica to the root pathogen Phytophthora citricola increased under elevated CO{sub 2}

  18. Changes in susceptibility of beech (Fagus sylvatica) seedlings towards Phytophthora citricola under the influence of elevated atmospheric CO2 and nitrogen fertilization

    International Nuclear Information System (INIS)

    Fleischmann, F.; Raidl, S.; Osswald, W.F.

    2010-01-01

    The growth-differentiation balance hypothesis (GDBH) predicts changes in susceptibility of plants against herbivores with changing resource availability. In the presented study we tested the validity of the GDBH for trees infected with a root pathogen. For this purpose Fagus sylvatica seedlings grown under different atmospheric CO 2 - and soil nitrogen regimes were infected with the root pathogen Phytophthora citricola. High nitrogen supply increased total biomass of beech regardless of the CO 2 -treatment, whereas elevated CO 2 enhanced biomass only in the high nitrogen treatment. The responses of beech under the different growing regimes to the Phytophthora root infection were not in line with the predictions of the GDBH. Enhanced susceptibility of beech against P. citricola was found in seedlings grown under elevated CO 2 and low nitrogen supply. Fifteen months after inoculation these plants were characterized by enhanced water use efficiency, by altered root-shoot ratios, and by enhanced specific root tip densities. - Susceptibility of Fagus sylvatica to the root pathogen Phytophthora citricola increased under elevated CO 2

  19. Differences in the photosynthetic UV-B response between European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst.) saplings

    International Nuclear Information System (INIS)

    Šprtová, M.; Marek, M.V.; Urban, O.; Kalina, J.; Špunda, V.

    2008-01-01

    Cloned saplings of Norway spruce (Picea abies (L) Karst.) and beech (Fagus sylvatica L.) (7 years old) were exposed to enhanced UV-B irradiation (+25%) continuously over three growing seasons (1999-2001). Selected parameters of variable chlorophyll alpha fluorescence and pigment composition were analysed in the late summer of the third growing season to evaluate the influence of long-term elevated UV-B irradiation on broadleaf and conifer tree species. To obtain information on the xanthophyll cycle, the de-epoxidation state (DEPS) was calculated. These tree species responded differentially to the long-term effects of enhanced UV-B radiation, Norway spruce was more sensitive compared to the European beech. The results show that in Norway spruce long-term exposure to enhanced UV-B radiation under field conditions caused negative changes at the level of primary photosynthetic reactions. Contrary to the beech, this had higher degree of UV-B protective responses. UV-B radiation is not effective stressor to its primary photosynthetic reaction

  20. Dendrite Injury Triggers DLK-Independent Regeneration

    Directory of Open Access Journals (Sweden)

    Michelle C. Stone

    2014-01-01

    Full Text Available Axon injury triggers regeneration through activation of a conserved kinase cascade, which includes the dual leucine zipper kinase (DLK. Although dendrites are damaged during stroke, traumatic brain injury, and seizure, it is not known whether mature neurons monitor dendrite injury and initiate regeneration. We probed the response to dendrite damage using model Drosophila neurons. Two larval neuron types regrew dendrites in distinct ways after all dendrites were removed. Dendrite regeneration was also triggered by injury in adults. Next, we tested whether dendrite injury was initiated with the same machinery as axon injury. Surprisingly, DLK, JNK, and fos were dispensable for dendrite regeneration. Moreover, this MAP kinase pathway was not activated by injury to dendrites. Thus, neurons respond to dendrite damage and initiate regeneration without using the conserved DLK cascade that triggers axon regeneration.

  1. The application of nanomaterials in controlled drug delivery for bone regeneration.

    Science.gov (United States)

    Shi, Shuo; Jiang, Wenbao; Zhao, Tianxiao; Aifantis, Katerina E; Wang, Hui; Lin, Lei; Fan, Yubo; Feng, Qingling; Cui, Fu-zhai; Li, Xiaoming

    2015-12-01

    Bone regeneration is a complicated process that involves a series of biological events, such as cellular recruitment, proliferation and differentiation, and so forth, which have been found to be significantly affected by controlled drug delivery. Recently, a lot of research studies have been launched on the application of nanomaterials in controlled drug delivery for bone regeneration. In this article, the latest research progress in this area regarding the use of bioceramics-based, polymer-based, metallic oxide-based and other types of nanomaterials in controlled drug delivery for bone regeneration are reviewed and discussed, which indicates that the controlling drug delivery with nanomaterials should be a very promising treatment in orthopedics. Furthermore, some new challenges about the future research on the application of nanomaterials in controlled drug delivery for bone regeneration are described in the conclusion and perspectives part. Copyright © 2015 Wiley Periodicals, Inc.

  2. Pulp-dentin Regeneration: Current State and Future Prospects.

    Science.gov (United States)

    Cao, Y; Song, M; Kim, E; Shon, W; Chugal, N; Bogen, G; Lin, L; Kim, R H; Park, N-H; Kang, M K

    2015-11-01

    The goal of regenerative endodontics is to reinstate normal pulp function in necrotic and infected teeth that would result in reestablishment of protective functions, including innate pulp immunity, pulp repair through mineralization, and pulp sensibility. In the unique microenvironment of the dental pulp, the triad of tissue engineering would require infection control, biomaterials, and stem cells. Although revascularization is successful in resolving apical periodontitis, multiple studies suggest that it alone does not support pulp-dentin regeneration. More recently, cell-based approaches in endodontic regeneration based on pulpal mesenchymal stem cells (MSCs) have demonstrated promising results in terms of pulp-dentin regeneration in vivo through autologous transplantation. Although pulpal regeneration requires the cell-based approach, several challenges in clinical translation must be overcome-including aging-associated phenotypic changes in pulpal MSCs, availability of tissue sources, and safety and regulation involved with expansion of MSCs in laboratories. Allotransplantation of MSCs may alleviate some of these obstacles, although the long-term stability of MSCs and efficacy in pulp-dentin regeneration demand further investigation. For an alternative source of MSCs, our laboratory developed induced MSCs (iMSCs) from primary human keratinocytes through epithelial-mesenchymal transition by modulating the epithelial plasticity genes. Initially, we showed that overexpression of ΔNp63α, a major isoform of the p63 gene, led to epithelial-mesenchymal transition and acquisition of stem characteristics. More recently, iMSCs were generated by transient knockdown of all p63 isoforms through siRNA, further simplifying the protocol and resolving the potential safety issues of viral vectors. These cells may be useful for patients who lack tissue sources for endogenous MSCs. Further research will elucidate the level of potency of these iMSCs and assess their

  3. Leaf morphology and phenology of Beech (Fagus sylvatica L.) are linked to environmental conditions depending on the altitudinal origin

    Science.gov (United States)

    Capdevielle-Vargas, Renee; Schuster, Christina; Estrella, Nicole; Menzel, Annette

    2014-05-01

    One of the principal responses of temperate climate trees to climate warming, besides migration, will be in-situ adaptation/evolution. For both, germination and growth rates can have a strong impact on survival and long-term recruitment and establishment of a species. Leaf morphology traits, together with phenology, are relevant to the study of inherent capacities of plants to adapt to an ever changing climate, especially in alpine regions, where a rapid warming has been observed in the last decades. The aim of this study was to evaluate the changes in possible adaptive traits (e.g. leaf morphology and phenology) of Beech (Fagus sylvatica L.) and to asses a decisive component of the survival strategy of this important broadly distributed Central European tree species. We collected beech seeds at six sites along two transects of a south- (900, 1000 and 1100-1400 m.a.s.l.) and a north-facing slope (800, 900 and 1100 m.a.s.l.) in 2011 (mast year) near Garmisch-Partenkirchen, Germany. All the seeds were stratified before sowing; 150 seeds were selected from each site and sowed (at the beginning of the spring) in square containers in a greenhouse under the same climatic conditions; seven phenological stages were defined following a modified beech germination key and the phenology of every seed was recorded three times a week. Harvesting took place 38/42 days after sowing and the specific leaf area (SLA), biomass, and leaf morphology (lamina length and width) were recorded for each seedling. Seeds from lower sites of the two transects presented a poorer germination rates (e.g. 30% for the south 900 m.a.s.l. site) and (75% for the north 800 m.a.s.l. site) when compared to seeds originating from higher elevations within the same transect. The highest germination percentages (98 and 85%) were observed in seeds originating from the highest elevations (e.g. 1100-1400 m.a.s.l. of the south site and 1100 m.a.s.l. of the north site, respectively). Although no significant

  4. Irradiation inhibits the regeneration of aneurogenic limbs

    International Nuclear Information System (INIS)

    Wallace, H.; Maden, M.

    1976-01-01

    The developing arms of axolotl larvae from the 2-digit stage onward and the aneurogenic arms of surgically denervated larvae maintained in parabiosis are able to regenerate after amputation. Such regeneration is uniformly inhibited by local irradiation of the arm, whether innervated or not. This demonstration refutes a recent hypothesis that x-rays interfere with a special activity of nerves required for regeneration, and supports the earlier concept that x-rays act directly on those cells which must proliferate to form the regenerated tissues

  5. Early regulation of axolotl limb regeneration.

    Science.gov (United States)

    Makanae, Aki; Satoh, Akira

    2012-10-01

    Amphibian limb regeneration has been studied for a long time. In amphibian limb regeneration, an undifferentiated blastema is formed around the region damaged by amputation. The induction process of blastema formation has remained largely unknown because it is difficult to study the induction of limb regeneration. The recently developed accessory limb model (ALM) allows the investigation of limb induction and reveals early events of amphibian limb regeneration. The interaction between nerves and wound epidermis/epithelium is an important aspect of limb regeneration. During early limb regeneration, neurotrophic factors act on wound epithelium, leading to development of a functional epidermis/epithelium called the apical epithelial cap (AEC). AEC and nerves create a specific environment that inhibits wound healing and induces regeneration through blastema formation. It is suggested that FGF-signaling and MMP activities participate in creating a regenerative environment. To understand why urodele amphibians can create such a regenerative environment and humans cannot, it is necessary to identify the similarities and differences between regenerative and nonregenerative animals. Here we focus on ALM to consider limb regeneration from a new perspective and we also reported that focal adhesion kinase (FAK)-Src signaling controlled fibroblasts migration in axolotl limb regeneration. Copyright © 2012 Wiley Periodicals, Inc.

  6. Angiogenesis is inhibitory for mammalian digit regeneration

    Science.gov (United States)

    Yu, Ling; Yan, Mingquan; Simkin, Jennifer; Ketcham, Paulina D.; Leininger, Eric; Han, Manjong

    2014-01-01

    Abstract The regenerating mouse digit tip is a unique model for investigating blastema formation and epimorphic regeneration in mammals. The blastema is characteristically avascular and we previously reported that blastema expression of a known anti‐angiogenic factor gene, Pedf, correlated with a successful regenerative response (Yu, L., Han, M., Yan, M., Lee, E. C., Lee, J. & Muneoka, K. (2010). BMP signaling induces digit regeneration in neonatal mice. Development, 137, 551–559). Here we show that during regeneration Vegfa transcripts are not detected in the blastema but are expressed at the onset of differentiation. Treating the amputation wound with vascular endothelial growth factor enhances angiogenesis but inhibits regeneration. We next tested bone morphogenetic protein 9 (BMP9), another known mediator of angiogenesis, and found that BMP9 is also a potent inhibitor of digit tip regeneration. BMP9 induces Vegfa expression in the digit stump suggesting that regenerative failure is mediated by enhanced angiogenesis. Finally, we show that BMP9 inhibition of regeneration is completely rescued by treatment with pigment epithelium‐derived factor. These studies show that precocious angiogenesis is inhibitory for regeneration, and provide compelling evidence that the regulation of angiogenesis is a critical factor in designing therapies aimed at stimulating mammalian regeneration. PMID:27499862

  7. 3D printing strategies for peripheral nerve regeneration.

    Science.gov (United States)

    Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D

    2018-03-23

    After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.

  8. Diffusion tensor tractography reveals muscle reconnection during axolotl limb regeneration.

    Directory of Open Access Journals (Sweden)

    Cheng-Han Wu

    Full Text Available Axolotls have amazing ability to regenerate their lost limbs. Our previous works showed that after amputation the remnant muscle ends remained at their original location whilst sending satellite cells into the regenerating parts to develop into early muscle fibers in the late differentiation stage. The parental and the newly formed muscle fibers were not connected until very late stage. The present study used non-invasive diffusion tensor imaging (DTI to monitor weekly axolotl upper arm muscles after amputation of their upper arms. DTI tractography showed that the regenerating muscle fibers became visible at 9-wpa (weeks post amputation, but a gap was observed between the regenerating and parental muscles. The gap was filled at 10-wpa, indicating reconnection of the fibers of both muscles. This was confirmed by histology. The DTI results indicate that 23% of the muscle fibers were reconnected at 10-wpa. In conclusion, DTI can be used to visualize axolotls' skeletal muscles and the results of muscle reconnection were in accordance with our previous findings. This non-invasive technique will allow researchers to identify the timeframe in which muscle fiber reconnection takes place and thus enable the study of the mechanisms underlying this reconnection.

  9. Towards Regeneration of Articular Cartilage

    Science.gov (United States)

    Iwamoto, Masahiro; Ohta, Yoichi; Larmour, Colleen; Enomoto-Iwamoto, Motomi

    2014-01-01

    Articular cartilage is classified into permanent hyaline cartilage and has significant differences in structure, extracelluar matrix components, gene expression profile, and mechanical property from transient hyaline cartilage found in growth plate. In the process of synovial joint development, articular cartilage is originated from the interzone, developing at the edge of the cartilaginous anlagen, it establishes zonal structure over time and supports smooth movement of the synovial joint through life. The cascade actions of key regulators such as Wnts, GDF5, Erg, and PTHLH coordinate sequential steps of articular cartilage formation. Articular chondrocytes are restrictedly controlled not to differentiate into a hypertrophic stage by autocrine and paracrine factors and extracerllular matrix microenvironment, but retain potential to undergo hypertrophy. The basal calcified zone of articular cartilage is connected with subchondral bone, but not invaded by blood vessels nor replaced by bone, which is highly contrasted with the growth plate. Articular cartilage has limited regenerative capacity, but likely possesses and potentially uses intrinsic stem cell source in the superficial layer, Ranvier’s groove, the intra-articular tissues such as synovium and fat pad, and marrow below the subchondral bone. Considering the biological views on articular cartilage, several important points are raised for regeneration of articular cartilage. We should evaluate the nature of regenerated cartilage as permanent hyaline cartilage and not just hyaline cartilage. We should study how a hypertrophic phenotype of transplanted cells can be lastingly suppressed in regenerating tissue. Further, we should develop the methods and reagents to activate recruitment of intrinsic stem/progenitor cells into the damaged site. PMID:24078496

  10. The Amount of Regenerated Heat Inside the Regenerator of a Stirling Engine

    Directory of Open Access Journals (Sweden)

    J. Škorpík

    2008-01-01

    Full Text Available The paper deals with analytical computing of the regenerated heat inside the regenerator of a Stirling engine. The total sum of the regenerated heat is constructed as a function of the crank angle in the case of Schmidt’s idealization. 

  11. Beech tree analyses in the Bohemian/Austrian/Bavarian frontier region; Fallstudie Buche im Dreilaendereck Boehmen/Oberoesterreich/Bayern

    Energy Technology Data Exchange (ETDEWEB)

    Kirchner, M. [GSF - Forschungszentrum fuer Umwelt und Gesundheit GmbH, Muenchen (Germany). Inst. fuer Oekologische Chemie; Baumgarten, M.; Matyssek, R. [Muenchen Univ., Freising (DE). Lehrstuhl fuer Forstbotanik] [and others

    2000-08-01

    The condition of beech trees was investigated in six forest stands in the Bayerischer Wald and Boehmerwald mountains between 1995 and 1997 in order to establish the interdependence between tree conditions, the prevailing natural and anthropogenic site factors, and air pollution especially with groundlevel ozone. Details of the investigations are presented. Although a potential long-term effect of ozone cannot be excluded, the damage observed in beech trees in this region since the eighties is assumed to be caused not by a single factor but by complex interaction patterns between several anthropogenic and natural factors. [German] Es erfolgte im Untersuchungsgebiet Bayerischer Wald/Boehmerwald im Zeitraum 1995 bis 1997 eine detaillierte Zustandscharakterisierung von Altbuchen an sechs Standorten. Im Rahmen der Gesamtuntersuchung sollte geklaert werden, ob Zusammenhaenge zwischen dem Baumzustand und den herrschenden natuerlichen und anthropogenen Standortfaktoren und Luftbelastungen mit Schwerpunkt des bodennahen Ozons bestehen. An Hand kontinuierlicher Ozonmessungen konnte bestaetigt werden, dass die Konzentration des bodennahen Ozons im wesentlichen eine Funktion der Meereshoehe ist; somit ist an Hochlagenstandorten von hoeheren Immissionen auszugehen. Bei den moeglicherweise besser an photooxidativen Stress akklimatisierten Hochlagenbuchen waren die Schaeden bei erhoehter Ozonbelastung geringer ausgepraegt als bei Tieflagenbuchen. Fuer die Hypothese, wonach man eine staerkere Schaedigung der Hochlagenbestaende zu erwarten hat, wurde keine Bestaetigung gefunden. Inositol wird seit einiger Zeit als sensitiver Indikator diskutiert, der auf veraenderte Umweltbedingungen reagiert. Die Inositolkonzentration in Sonnenblaettern von Altbuchen im Bayerischen Wald war in 1995 um ca. 50% geringer als in 1996. Bei den Jungbuchen im Phytotronenexperiment kam es bei anhaltendem Ozonstress und zunehmender Schaedigung zu einer starken Reduktion der Inositolkonzentration in

  12. Potential impact of global warming on the range of Spruce, Fir, Beech and sessile Oak in France

    International Nuclear Information System (INIS)

    Piedallu, Christian; Perez, Vincent; Gegout, Jean-Claude; Lebourgeois, Francois; Bertrand, Romain

    2009-01-01

    There have been many studies all over the world that forecast the impact of global warming on vegetation but there is little information currently available to assess its consequences on French forests. The authors studied the range of four common species - spruce, fir, beech and sessile oak - so as to determine their ecology as accurately as possible and assess their sensitivity to global warming. Their range over the period from 1961-1990 was modelled and mapped for the whole of France using ecological variables that characterize climate, water supply, and soil nutrition. The models constructed predict effects from temperature, the water resource, water-logging and the trophic level of soils that are consistent with empirical knowledge about these species. Changes in the probabilities of presence during the 21. century investigated by simulating the A2 and B2 scenarios of the HadCM3 climate model. Changes in climate as predicted by this model would lead to a decrease of the probabilities of presence for all four species initially in the first part of the 21. century at the outer limits of their ranges and then a very significant drop in most plains and medium altitude upland areas, even according to the most optimistic forecasts under scenario B2. The reduction in the forest surface areas that are favourable to the species investigated for the period 2070-2100 is estimated, depending on the scenario, to be between 92% and 99% for spruce, 80% and 93% for beech, 63% and 83% for fir and 43% and 83% for sessile oak. These forecasted changes are very significant in comparison with the current conditions that are favourable to the presence of these species for which edaphic variables act as a local filter within the overall climate envelope. The authors conclude by underscoring the value of these tools for identifying and mapping the most vulnerable areas so as to be in a position to track the behaviour of these species in these areas and determine the appropriate

  13. Temperature responses of growth and wood anatomy in European beech saplings grown in different carbon dioxide concentrations

    International Nuclear Information System (INIS)

    Overdieck, D.; Ziche, D.; Bottcher-Jungclaus, K.

    2007-01-01

    This study investigated relationships between wood anatomical properties, growth, and mass allocation of well-watered beech saplings growing in different temperature and carbon dioxide (CO 2 ) regimes. The study was conducted to test whether growth was enhanced by increasing temperature and CO 2 , as well as to determine whether the leaf area to stem cross-sectional area ratio, leaf mass ratio, and leaf area ratio declined with increasing temperature. The study also investigated the hypothesis that vessel member and size decreases with increasing temperature and CO 2 as well as the hypothesis that wood parenchyma content declines with increasing temperature and increases in response to elevated CO 2 . The beech saplings were grown in 7-1 pots for 2.5 years in field-phytotron chambers supplied with ambient or elevated CO 2 . Temperatures in the chambers ranged in increments of 2 degrees C. Soil was not fertilized and soil water and air humidity were kept constant. Data were evaluated by regression analysis. Results of the study showed that stem diameter was significantly larger at increased temperatures. In addition, stems were taller, and leaf area and stem mass were greater. The allocation pattern was influenced by temperature, as leaf mass ratio and leaf area ratio decreased with increasing temperature. Elevated CO 2 enhanced height growth by 8.8 per cent, and decreased coarse root mass and total mass by 10.3 per cent. The root/shoot ratio was decreased by 11.7 per cent. At final harvest, a synergistic interaction was observed between elevated CO 2 and temperature yielded trees that were 3.2 per cent taller at -4 degrees C, and 12.7 per cent taller at 4 degrees C than trees grown in ambient CO 2 . After 2.5 seasons, the cross-sectional area of the oldest stem part was approximately 32 per cent greater in the 4 degree C treatment than the -4 degree C treatment. In the final year, approximately 67 per cent more leaf area per unit tree ring area was produced in the

  14. Purifying and regenerating hydrocarbon oils

    Energy Technology Data Exchange (ETDEWEB)

    1931-11-19

    Hydrocarbons are freed from sulfur-containing compounds, colloidal asphaltic bodies and unstable unsaturated substances by treatment with a small amount of dilute sulfuric acid and a salt of a trivalent cation, such as ferric chloride or sulfate. Hydrocarbons specified are petroleum, crude benzol, low temperature tars, shale oil or vapor-phase cracked spirit. Motor spirit or lubricating oil distillates are refined and finally distilled. The acid reagent may be regenerated by filtering through sand or asbestos. Used lubricating oils may be treated similarly and after removal of refining agent, the oil is heated with an adsorbent and decolorizing material and then filtered.

  15. Ash recycling to spruce and beech stands effects on nutrients, growth, nitrogen dynamics and carbon balance; Askaaterfoering till gran- och bokbestaand - effekter paa naering, tillvaext, kvaevedynamik och kolbalans

    Energy Technology Data Exchange (ETDEWEB)

    Thelin, Gunnar

    2006-03-15

    Ash recycling is an important part in a modern, sustainable forestry, especially in whole-tree harvest systems. Nutrients lost at harvest are returned to the forest with the wood-ash. In the project the effects of ash treatment on needle and leaf chemistry, tree growth, soil chemistry, soil water chemistry, and carbon and nitrogen dynamics were studied on 23 Norway spruce sites in south-western Sweden and in ten European beech sites in Scania, southern Sweden. On some of the sites there were previously established ash recycling experiments, but on a majority of the sites ash recycling was performed without experimental lay-out and ash and control plots were established afterwards. The most common dose was two tons of self hardened crushed wood-ash and two tons of Mg-lime. On average seven to eight years after ash recycling the results were 1. increased exchangeable stores of base cations in the soil in the beech and the spruce stands 2. increased base saturation in the beech and the spruce stands and increased BC/Al in the spruce stands 3. increased concentrations and ratios to N of P, Ca, Zn, and S in the needles, the increased P-values are especially important since P is close to or below deficiency levels in a majority of the spruce stands 4. decreased K-concentration in the beech leaves 5. increased tree growth with on average 14 % in the ash treated spruce stands compared to the control plots 6. increased carbon and nitrogen amounts in the biomass in the spruce stands 7. tendencies towards increased amounts of carbon and nitrogen in the soil in the beech stands and no effect in the soil in the spruce stands 8. increased concentrations of Ca, Mg, and SO{sub 4} and no effect on ANC in the soil water 9. no effect on potential net mineralization but increased potential nitrification rates 10. decreased concentration of nitrate in the soil water in the beech stands and no effect in the spruce stands 11. lower system N losses in the beech stands and possibly in the

  16. Immission-load-related dynamics of S-SO42− in precipitation and in lysimetric solutions penetrating through beech ecosystems

    Directory of Open Access Journals (Sweden)

    Kukla Ján

    2017-12-01

    Full Text Available The paper presents the results of a 23-year study of sulphate sulphur dynamics in beech ecosystems exposed to different immission loads. The amounts of S-SO42− in precipitation water entering the ecosystems were: the Kremnické vrchy Mts, a clear-cut area 519 kg ha−1 (24.7 kg ha−1 per year, a beech forest 476 kg ha−1 (22.7 kg ha−1 per year; the Štiavnické vrchy Mts an open place 401 kg ha−1 (24.6 kg ha−1 per year, a beech forest 324 kg ha−1 (19.1 kg ha−1 per year. The average SO42− concentrations in lysimetric solutions penetrating through surface humus to a depth of Cambisol 10 and 25 cm were increased as follows: in the Kremnické vrchy Mts from 12.71 to 16.17 mg l−1 and in the Štiavnické vrchy Mts from 18.73 to 28.80 mg l−1. The S-SO4−2 amounts penetrating the individual soil layers in the Kremnické vrchy Mts were as follows: in case of surface humus on clear-cut area 459 kg ha−1 (20.9 kg ha−1 per year, in beech forest 433 kg ha−1 (19.7 kg ha−1 per year; below 10 cm organo-mineral layer of the mentioned plots penetrated 169–171 kg ha−1 (7.7–7.8 kg ha−1 per year, and below 25 cm mineral layer 155–255 kg ha−1 (7.1−11.6 kg ha−1 per year – a higher amount was found on clear-cut area with an episodic lateral flow of soil solutions. In beech forest of the Štiavnické vrchy Mts penetrated below surface humus 424 kg ha−1 S-SO42− (18.9 kg ha−1 per year, below 10 cm mineral layer 458 kg ha−1 S-SO42− (19.9 kg ha−1 per year, and below 25 cm mineral layer as much as 599 kg ha−1 S-SO42− (26.0 kg ha−1 per year. This fact was caused by frequent lateral flow of soil solutions. The results indicate that the assumption about lower immission load of the beech ecosystem in the Kremnické vrchy Mts is wrong, at least in the case of S-SO42−. The testing has revealed that the studied beech ecosystems differ very significantly in sulphur amounts penetrating under 0.10 m and 0.25 m. The

  17. Regeneration performance of CO2-rich solvents by using membrane vacuum regeneration technology: Relationships between absorbent structure and regeneration efficiency

    International Nuclear Information System (INIS)

    Yan, Shuiping; Fang, Mengxiang; Wang, Zhen; Luo, Zhongyang

    2012-01-01

    Highlights: ► MVR may be viable to successfully use less valuable heat to replace high grade steam. ► Increasing OH and amine groups will increase the regeneration efficiency. ► Absorbents with a four carbon chain length will be more attractive to MVR. ► Amino acid salts will be more appropriate for MVR. ► HRM conducted at ambient pressure and low temperature is inferior to MVR. -- Abstract: In order to give a better understanding for the selection of suitable absorbents for the novel membrane vacuum regeneration technology (MVR) which has the potential to reduce CO 2 energy requirement by utilizing the waste heat or low-grade energy, an experimental study to determine the relationships between chemical structure and vacuum regeneration behavior of CO 2 absorbents at 70 °C and 10 kPa was performed. Eleven typical absorbents with different functional groups in their chemical structures were investigated in terms of vacuum regeneration efficiencies. Results showed that the regeneration efficiency decreased with an increase of number of activated hydrogen atom in amine group and decreased with the number of hydroxyl group. Especially, more attention should be paid to these alkanolamines with one hydrogen atom in amine group and two or more hydroxyl groups in the structures due to their better comprehensive performance in regeneration, absorbent loss and CO 2 absorption aspects. Increasing the carbon chain length and amine groups in the absorbent structure contributed to the improvement of regeneration performance and reduction of absorbent volatile loss. These absorbents with a four carbon chain length bonded at amine group might be more attractive to MVR. Furthermore, polyamines were superior to monoamines in terms of higher regeneration efficiencies and lower absorbent losses. Additionally, the individual effects of the potassium carboxylate group and hydroxymethylene group were also compared in this study. Results showed that amino acid salts were more

  18. Perspectives on stem cell therapy for cardiac regeneration. Advances and challenges.

    Science.gov (United States)

    Choi, Sung Hyun; Jung, Seok Yun; Kwon, Sang-Mo; Baek, Sang Hong

    2012-01-01

    Ischemic heart disease (IHD) accelerates cardiomyocyte loss, but the developing stem cell research could be useful for regenerating a variety of tissue cells, including cardiomyocytes. Diverse sources of stem cells for IHD have been reported, including embryonic stem cells, induced pluripotent stem cells, skeletal myoblasts, bone marrow-derived stem cells, mesenchymal stem cells, and cardiac stem cells. However, stem cells have unique advantages and disadvantages for cardiac tissue regeneration, which are important considerations in determining the specific cells for improving cell survival and long-term engraftment after transplantation. Additionally, the dosage and administration method of stem cells need to be standardized to increase stability and efficacy for clinical applications. Accordingly, this review presents a summary of the stem cell therapies that have been studied for cardiac regeneration thus far, and discusses the direction of future cardiac regeneration research for stem cells.

  19. Microwave Regenerable Air Purification Device

    Science.gov (United States)

    Atwater, James E.; Holtsnider, John T.; Wheeler, Richard R., Jr.

    1996-01-01

    The feasibility of using microwave power to thermally regenerate sorbents loaded with water vapor, CO2, and organic contaminants has been rigorously demonstrated. Sorbents challenged with air containing 0.5% CO2, 300 ppm acetone, 50 ppm trichloroethylene, and saturated with water vapor have been regenerated, singly and in combination. Microwave transmission, reflection, and phase shift has also been determined for a variety of sorbents over the frequency range between 1.3-2.7 GHz. This innovative technology offers the potential for significant energy savings in comparison to current resistive heating methods because energy is absorbed directly by the material to be heated. Conductive, convective and radiative losses are minimized. Extremely rapid heating is also possible, i.e., 1400 C in less than 60 seconds. Microwave powered thermal desorption is directly applicable to the needs of Advance Life Support in general, and of EVA in particular. Additionally, the applicability of two specific commercial applications arising from this technology have been demonstrated: the recovery for re-use of acetone (and similar solvents) from industrial waste streams using a carbon based molecular sieve; and the separation and destruction of trichloroethylene using ZSM-5 synthetic zeolite catalyst, a predominant halocarbon environmental contaminant. Based upon these results, Phase II development is strongly recommended.

  20. Liver Development, Regeneration, and Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Janet W. C. Kung

    2010-01-01

    Full Text Available The identification of putative liver stem cells has brought closer the previously separate fields of liver development, regeneration, and carcinogenesis. Significant overlaps in the regulation of these processes are now being described. For example, studies in embryonic liver development have already provided the basis for directed differentiation of human embryonic stem cells and induced pluripotent stem cells into hepatocyte-like cells. As a result, the understanding of the cell biology of proliferation and differentiation in the liver has been improved. This knowledge can be used to improve the function of hepatocyte-like cells for drug testing, bioartificial livers, and transplantation. In parallel, the mechanisms regulating cancer cell biology are now clearer, providing fertile soil for novel therapeutic approaches. Recognition of the relationships between development, regeneration, and carcinogenesis, and the increasing evidence for the role of stem cells in all of these areas, has sparked fresh enthusiasm in understanding the underlying molecular mechanisms and has led to new targeted therapies for liver cirrhosis and primary liver cancers.

  1. Regeneration of Pelargonium in vitro

    Directory of Open Access Journals (Sweden)

    Agnieszka Wojtania

    2013-12-01

    Full Text Available Pelargonium sp. has been a subject of numerous studies to deterimine the effec tiveness of in vitro techniques to produce a large number of pathogen-free plants. Regeneration of pelargonium plants from the different initial explants as well via organogenesis as via somatic embryogenesis has been obtained. The most effective adventitious shoot formation has been achieved from shoot tips and axillary buds using cytokinin or cytokinin/auxin combinations. Leaf explants, whose general have lower organogenic potency, regenerate better in the presence of thidiazuron. This growth regulator stimulate the somatic embryos production from hypocotyl and cotyledone explants too. The main problem in tissue culture propagation of Pelargonium has been the high tendency to formation of vigorously growing callus with low organogenic potency and rapid senescence of cultures. Moreover, the significant differen ces in requirements to the medium composition (minerals, organic compounds and growth regulators between Pelargonium cultivars has been observed. This makes difficult to develop an universaI method of Pelargonium micropropagation.

  2. New tides: using zebrafish to study renal regeneration.

    Science.gov (United States)

    McCampbell, Kristen K; Wingert, Rebecca A

    2014-02-01

    Over the past several decades, the zebrafish has become one of the major vertebrate model organisms used in biomedical research. In this arena, the zebrafish has emerged as an applicable system for the study of kidney diseases and renal regeneration. The relevance of the zebrafish model for nephrology research has been increasingly appreciated as the understanding of zebrafish kidney structure, ontogeny, and the response to damage has steadily expanded. Recent studies have documented the amazing regenerative characteristics of the zebrafish kidney, which include the ability to replace epithelial populations after acute injury and to grow new renal functional units, termed nephrons. Here we discuss how nephron composition is conserved between zebrafish and mammals, and highlight how recent findings from zebrafish studies utilizing transgenic technologies and chemical genetics can complement traditional murine approaches in the effort to dissect how the kidney responds to acute damage and identify therapeutics that enhance human renal regeneration. Copyright © 2014 Mosby, Inc. All rights reserved.

  3. Mobilising voluntary contributions in public urban regeneration – a review

    DEFF Research Database (Denmark)

    Larsen, Jacob Norvig; Jensen, Jesper Ole; Agger, Annika

    Research on volunteerism indicates that one third of all adults in Denmark regularly contribute with voluntary labour in social relief work, community-based organizations, non-governmental organizations, or otherwise. In this paper we ask if and how urban regeneration might benefit from...... in relation to public policy arenas and activities, particularly within urban policy and the community development fields. A categorization is proposed as regards different ways and models of civic engagement and major challenges are outlined. The paper is first step of a research project exploring potential...... the apparently strong growth in voluntarism. Although there seems to be a large potential for involving volunteers and voluntary organisations, systematic analysis of recent years’ urban regeneration projects in Denmark shows that the sustainability of voluntary contributions is limited. While initial enrolling...

  4. Hepatic resection and regeneration. Past and present

    International Nuclear Information System (INIS)

    Hatsuse, Kazuo

    2007-01-01

    Hepatic surgery has been performed on condition that the liver regenerates after hepatic resection, and the development of liver anatomy due to Glisson, Rex, and Couinaud has thrown light on hepatic surgery Understanding of feeding and drainage vessels became feasible for systemic hepatic resection; however, it seems to have been the most important problem to control the bleeding during hepatic resection. New types of devices such as cavitron ultrasonic surgical aspirator (CUSA) and Microwave coagulation were exploited to control blood loss during hepatic surgery. Pringle maneuver for exclusion feeding vessels of the liver and the decrease of central venous pressure during anesthesia enabled further decrease of blood loss. Nowadays, 3D-CT imaging may depict feeding and drainage vessels in relation to liver mass, and surgeons can simulate hepatic surgery in virtual reality before surgery, allowing hepatectomy to be performed without blood transfusion. Thus, hepatic resection has been a safe procedure, but there's been a significant research on how much of the liver can be resected without hepatic failure. A prediction scoring system based on ICGR15, resection rates, and age is mostly reliable in some criteria. Even if hepatectomy is performed with a good prediction score, the massive bleeding and associated infection may induce postoperative hepatic failure, while the criteria of postoperative hepatic failure have not yet established. Hepatic failure is supposed to be induced by the apoptosis of mature hepatocytes and necrosis originated from microcirculation disturbance of the liver. Prostaglandin E1 for the improvement of microcirculation, steroid for the inhibition of cytokines inducing apoptosis, and blood purification to exclude cytokines have been tried separately or concomitantly. New therapeutic approaches, especially hepatic regeneration from the stem cell, are expected. (author)

  5. Impaired peripheral nerve regeneration in type-2 diabetic mouse model.

    Science.gov (United States)

    Pham, Vuong M; Tu, Nguyen Huu; Katano, Tayo; Matsumura, Shinji; Saito, Akira; Yamada, Akihiro; Furue, Hidemasa; Ito, Seiji

    2018-01-01

    Peripheral neuropathy is one of the most common and serious complications of type-2 diabetes. Diabetic neuropathy is characterized by a distal symmetrical sensorimotor polyneuropathy, and its incidence increases in patients 40 years of age or older. In spite of extensive research over decades, there are few effective treatments for diabetic neuropathy besides glucose control and improved lifestyle. The earliest changes in diabetic neuropathy occur in sensory nerve fibers, with initial degeneration and regeneration resulting in pain. To seek its effective treatment, here we prepared a type-2 diabetic mouse model by giving mice 2 injections of streptozotocin and nicotinamide and examining the ability for nerve regeneration by using a sciatic nerve transection-regeneration model previously established by us. Seventeen weeks after the last injection, the mice exhibited symptoms of type-2 diabetes, that is, impaired glucose tolerance, decreased insulin level, mechanical hyperalgesia, and impaired sensory nerve fibers in the plantar skin. These mice showed delayed functional recovery and nerve regeneration by 2 weeks compared with young healthy mice and by 1 week compared with age-matched non-diabetic mice after axotomy. Furthermore, type-2 diabetic mice displayed increased expression of PTEN in their DRG neurons. Administration of a PTEN inhibitor at the cutting site of the nerve for 4 weeks promoted the axonal transport and functional recovery remarkably. This study demonstrates that peripheral nerve regeneration was impaired in type-2 diabetic model and that its combination with sciatic nerve transection is suitable for the study of the pathogenesis and treatment of early diabetic neuropathy. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  6. Effect of activation on the porous structure and the strain and strength properties of beech wood biocarbon

    Science.gov (United States)

    Shpeizman, V. V.; Orlova, T. S.; Spitsyn, A. A.; Ponomarev, D. A.; Bogdanovich, N. I.; Martinez-Fernández, J.

    2017-01-01

    The effect of activation on the size, specific volume, and surface area of pores in a monolithic biomorphic material obtained by carbonization of beech wood is studied. It is shown that under optimal activation mode with a steam heated to 970°C, the total pore volume and surface, determined by adsorption curves, increased by 20 and 18 times, respectively. With the use of high-precision interferometric procedure, strain curves are obtained under uniaxial compression with a stepwise loading, and the strain rate is measured with a step of moving of 325 nm for activated and nonactivated samples. Despite an increase in porosity, the strength and maximum deformation of the samples do not decrease. The behavior of the strain rate jumps is analyzed in the micro- and nanometer range. It is shown that the maximum size of the micrometer jumps (4 μm) correlates well with the average size of the possible strain area in the samples (the average distance between the pores of small size), and the minimum dimensions of the strain jumps are close to the size of mesopores. Assessment of the strain change and its rate upon activation indicates that the effect of activation on the strain and strength characteristics is defined by nanometer defects, the most likely of which are microand mesopores.

  7. Specific impacts of beech and Norway spruce on the structure and diversity of the rhizosphere and soil microbial communities.

    Science.gov (United States)

    Uroz, S; Oger, P; Tisserand, E; Cébron, A; Turpault, M-P; Buée, M; De Boer, W; Leveau, J H J; Frey-Klett, P

    2016-06-15

    The impacts of plant species on the microbial communities and physico-chemical characteristics of soil are well documented for many herbs, grasses and legumes but much less so for tree species. Here, we investigate by rRNA and ITS amplicon sequencing the diversity of microorganisms from the three domains of life (Archaea, Bacteria and Eukaryota:Fungi) in soil samples taken from the forest experimental site of Breuil-Chenue (France). We discovered significant differences in the abundance, composition and structure of the microbial communities associated with two phylogenetically distant tree species of the same age, deciduous European beech (Fagus sylvatica) and coniferous Norway spruce (Picea abies Karst), planted in the same soil. Our results suggest a significant effect of tree species on soil microbiota though in different ways for each of the three microbial groups. Fungal and archaeal community structures and compositions are mainly determined according to tree species, whereas bacterial communities differ to a great degree between rhizosphere and bulk soils, regardless of the tree species. These results were confirmed by quantitative PCR, which revealed significant enrichment of specific bacterial genera, such as Burkholderia and Collimonas, known for their ability to weather minerals within the tree root vicinity.

  8. The effect of temperature and heating rate on char properties obtained from solar pyrolysis of beech wood.

    Science.gov (United States)

    Zeng, Kuo; Minh, Doan Pham; Gauthier, Daniel; Weiss-Hortala, Elsa; Nzihou, Ange; Flamant, Gilles

    2015-04-01

    Char samples were produced from pyrolysis in a lab-scale solar reactor. The pyrolysis of beech wood was carried out at temperatures ranging from 600 to 2000°C, with heating rates from 5 to 450°C/s. CHNS, scanning electron microscopy analysis, X-ray diffractometry, Brunauer-Emmett-Teller adsorption were employed to investigate the effect of temperature and heating rate on char composition and structure. The results indicated that char structure was more and more ordered with temperature increase and heating rate decrease (higher than 50°C/s). The surface area and pore volume firstly increased with temperature and reached maximum at 1200°C then reduced significantly at 2000°C. Besides, they firstly increased with heating rate and then decreased slightly at heating rate of 450°C/s when final temperature was no lower than 1200°C. Char reactivity measured by TGA analysis was found to correlate with the evolution of char surface area and pore volume with temperature and heating rate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Increasing net CO2 uptake by a Danish beech forest during the period from 1996 to 2009

    DEFF Research Database (Denmark)

    Pilegaard, Kim; Ibrom, Andreas; Courtney, Michael

    2011-01-01

    and atmospheric CO2 concentration. The net CO2 exchange (NEE) was measured by the eddy covariance method. Ecosystem respiration (RE) was estimated from nighttime values and gross ecosystem exchange (GEE) was calculated as the sum of RE and NEE. Over the years the beech forest acted as a sink of on average of 157...... g C m−2 yr−1. In one of the years only, the forest acted as a small source. During 1996–2009 a significant increase in annual NEE was observed. A significant increase in GEE and a smaller and not significant increase in RE was also found. Thus the increased NEE was mainly attributed to an increase...... in GEE. The overall trend in NEE was significant with an average increase in uptake of 23 g C m−2 yr−2. The carbon uptake period (i.e. the period with daily net CO2 gain) increased by 1.9 days per year, whereas there was a non significant tendency of increase of the leafed period. This means...

  10. Fluorescence and electron microscopic investigations of the phloem of beeches, spruces and firs showing different degrees of damage symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, A.; Behnke, H.-D.; Horsch, F.; Filby, G.; Fund, N.; Gross, S.; Hanisch, B.; Kilz, E.; Seidel, A. (comps.)

    1986-04-01

    The phloem of beeches, spruces and firs showing different degrees of damage symptoms (standard damage classification 0-3) was investigated with microscopic methods to examine their possible infections with mycoplasma-like-organisms (MLO), rickettsia-like-bacteria (RLB), and viruses. During the growing seasons of the years 1984 and 1985 root-, stem- and branch parts of up to 39 trees growing in three different areas were removed at monthly intervals and subsequently screened. Prerequisite to these investigations is a knowledge of the composition of the secondary phloem in these trees and of cytological changes which occur during the differentiation of the different phloem cells. None of the many samples contained MLO, RLB or viruses, and the rare occurrence of single structures which could be misinterpreted as MLO is discussed. Judged by this negative result of an in-situ-localization in the phloem of damaged trees, MLO, RLB and viruses are excluded as a primary factor of the new forest damage - for which a systemic spread would be prerequisite-, while a predisposing role of viruses was not likely to be shown with the methods applied.

  11. Cardiac regeneration therapy: connections to cardiac physiology.

    Science.gov (United States)

    Takehara, Naofumi; Matsubara, Hiroaki

    2011-12-01

    Without heart transplantation, a large number of patients with failing hearts worldwide face poor outcomes. By means of cardiomyocyte regeneration, cardiac regeneration therapy is emerging with great promise as a means for restoring loss of cardiac function. However, the limited success of clinical trials using bone marrow-derived cells and myoblasts with heterogeneous constituents, transplanted at a wide range of cell doses, has led to disagreement on the efficacy of cell therapy. It is therefore essential to reevaluate the evidence for the efficacy of cell-based cardiac regeneration therapy, focusing on targets, materials, and methodologies. Meanwhile, the revolutionary innovation of cardiac regeneration therapy is sorely needed to help the millions of people who suffer heart failure from acquired loss of cardiomyocytes. Cardiac regeneration has been used only in limited species or as a developing process in the rodent heart; now, the possibility of cardiomyocyte turnover in the human heart is being revisited. In the pursuit of this concept, the use of cardiac stem/progenitor stem cells in the cardiac niche must be focused to usher in a second era of cardiac regeneration therapy for the severely injured heart. In addition, tissue engineering and cellular reprogramming will advance the next era of treatment that will enable current cell-based therapy to progress to "real" cardiac regeneration therapy. Although many barriers remain, the prevention of refractory heart failure through cardiac regeneration is now becoming a realistic possibility.

  12. Heat exchanger versus regenerator: A fundamental comparison

    NARCIS (Netherlands)

    Will, M.E.; Waele, de A.T.A.M.

    2005-01-01

    Irreversible processes in regenerators and heat exchangers limit the performance of cryocoolers. In this paper we compare the performance of cryocoolers, operating with regenerators and heat exchangers from a fundamental point of view. The losses in the two systems are calculated from the entropy

  13. Adventitious shoots induction and plant regeneration from ...

    African Journals Online (AJOL)

    A highly efficient regeneration system is a prerequisite step for successful genetic transformation of watermelon cultivars (Citrullus lanatus L.). The objective of this study was to establish efficient in vitro plant regeneration for three watermelon cultivars. To achieve optimal conditions for adventitious shoot induction, the ...

  14. Plant regeneration in wheat mature embryo culture

    African Journals Online (AJOL)

    Kamil Haliloğlu

    2011-11-09

    Nov 9, 2011 ... Success in genetic engineering of cereals depends on the callus formation and efficient plant regeneration system. Callus formation and plant regeneration of wheat mature embryos ... compiled by modification of methods previously mentioned in ..... of more and readily available nutrition than artificial cul-.

  15. Oak regeneration potential increased by shelterwood treatments

    Science.gov (United States)

    Richard C. Schlesinger; Ivan L. Sander; Kenneth R. Davidson

    1993-01-01

    In much of the Central Hardwood Forest Region, oak species are not regenerating well, even though large oak trees are common within the existing forests. The shelterwood method has been suggested as a potential tool for establishing and developing advanced regeneration where it is lacking. The 10-yr results from a study of several variants of the shelterwood method...

  16. Animal regeneration: ancestral character or evolutionary novelty?

    Science.gov (United States)

    Slack, Jonathan Mw

    2017-09-01

    An old question about regeneration is whether it is an ancestral character which is a general property of living matter, or whether it represents a set of specific adaptations to the different circumstances faced by different types of animal. In this review, some recent results on regeneration are assessed to see if they can throw any new light on this question. Evidence in favour of an ancestral character comes from the role of Wnt and bone morphogenetic protein signalling in controlling the pattern of whole-body regeneration in acoels, which are a basal group of bilaterian animals. On the other hand, there is some evidence for adaptive acquisition or maintenance of the regeneration of appendages based on the occurrence of severe non-lethal predation, the existence of some novel genes in regenerating organisms, and differences at the molecular level between apparently similar forms of regeneration. It is tentatively concluded that whole-body regeneration is an ancestral character although has been lost from most animal lineages. Appendage regeneration is more likely to represent a derived character resulting from many specific adaptations. © 2017 The Author.

  17. Axonal regeneration in zebrafish spinal cord

    Science.gov (United States)

    Hui, Subhra Prakash

    2018-01-01

    Abstract In the present review we discuss two interrelated events—axonal damage and repair—known to occur after spinal cord injury (SCI) in the zebrafish. Adult zebrafish are capable of regenerating axonal tracts and can restore full functionality after SCI. Unlike fish, axon regeneration in the adult mammalian central nervous system is extremely limited. As a consequence of an injury there is very little repair of disengaged axons and therefore functional deficit persists after SCI in adult mammals. In contrast, peripheral nervous system axons readily regenerate following injury and hence allow functional recovery both in mammals and fish. A better mechanistic understanding of these three scenarios could provide a more comprehensive insight into the success or failure of axonal regeneration after SCI. This review summarizes the present understanding of the cellular and molecular basis of axonal regeneration, in both the peripheral nervous system and the central nervous system, and large scale gene expression analysis is used to focus on different events during regeneration. The discovery and identification of genes involved in zebrafish spinal cord regeneration and subsequent functional experimentation will provide more insight into the endogenous mechanism of myelination and remyelination. Furthermore, precise knowledge of the mechanism underlying the extraordinary axonal regeneration process in zebrafish will also allow us to unravel the potential therapeutic strategies to be implemented for enhancing regrowth and remyelination of axons in mammals. PMID:29721326

  18. Hyperinnervation improves Xenopus laevis limb regeneration.

    Science.gov (United States)

    Mitogawa, Kazumasa; Makanae, Aki; Satoh, Akira

    2018-01-15

    Xenopus laevis (an anuran amphibian) shows limb regeneration ability between that of urodele amphibians and that of amniotes. Xenopus frogs can initiate limb regeneration but fail to form patterned limbs. Regenerated limbs mainly consist of cone-shaped cartilage without any joints or branches. These pattern defects are thought to be caused by loss of proper expressions of patterning-related genes. This study shows that hyperinnervation surgery resulted in the induction of a branching regenerate. The hyperinnervated blastema allows the identification and functional analysis of the molecules controlling this patterning of limb regeneration. This paper focuses on the nerve affects to improve Xenopus limb patterning ability during regeneration. The nerve molecules, which regulate limb patterning, were also investigated. Blastemas grown in a hyperinnervated forelimb upregulate limb patterning-related genes (shh, lmx1b, and hoxa13). Nerves projecting their axons to limbs express some growth factors (bmp7, fgf2, fgf8, and shh). Inputs of these factors to a blastema upregulated some limb patterning-related genes and resulted in changes in the cartilage patterns in the regenerates. These results indicate that additional nerve factors enhance Xenopus limb patterning-related gene expressions and limb regeneration ability, and that bmp, fgf, and shh are candidate nerve substitute factors. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation.

    Science.gov (United States)

    do Nascimento-Elias, Adriana Helena; Fresnesdas, Bruno César; Schiavoni, Maria Cristina Lopes; de Almeida, Natália Fernanda Gaspar; Santos, Ana Paula; de Oliveira Ramos, Jean; Junior, Wilson Marques; Barreira, Amilton Antunes

    2012-08-14

    Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco's modified Eagle's medium) can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM) and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres. Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth. In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth.

  20. The Vascular Niche in Tissue Repair: A Therapeutic Target for Regeneration

    OpenAIRE

    Rivera, Francisco J.; Silva, Maria Elena; Aigner, Ludwig

    2017-01-01

    Editorial on the Research Topic The Vascular Niche in Tissue Repair: A Therapeutic Target for Regeneration In mammals, although regeneration is quite restricted to a number of tissues and organs, this particular healing process is possible through the existence of tissue-resident stem/progenitor cells. Upon injury, these cells are activated, they proliferate, migrate, and differentiate into tissue-specific cells and functionally replace the damaged or lost cells. Besides this, angio...

  1. Complement components of nerve regeneration conditioned fluid influence the microenvironment of nerve regeneration

    Directory of Open Access Journals (Sweden)

    Guang-shuai Li

    2016-01-01

    Full Text Available Nerve regeneration conditioned fluid is secreted by nerve stumps inside a nerve regeneration chamber. A better understanding of the proteinogram of nerve regeneration conditioned fluid can provide evidence for studying the role of the microenvironment in peripheral nerve regeneration. In this study, we used cylindrical silicone tubes as the nerve regeneration chamber model for the repair of injured rat sciatic nerve. Isobaric tags for relative and absolute quantitation proteomics technology and western blot analysis confirmed that there were more than 10 complement components (complement factor I, C1q-A, C1q-B, C2, C3, C4, C5, C7, C8ß and complement factor D in the nerve regeneration conditioned fluid and each varied at different time points. These findings suggest that all these complement components have a functional role in nerve regeneration.

  2. The dependence of natural regeneration of forest trees on upper soil conditions and acidity at damaged sites in the Black Forest, Germany

    International Nuclear Information System (INIS)

    Littek, T.

    1993-06-01

    It was the goal of this study to investigate the influence of different upper soil conditions on the germination and establishment, as well as the growth, of young plants of various tree species. For this purpose, four test plots in the region of the Black Forest were laid out, in which, by various means of site preparation and fertilization, the upper soils were changed. Natural seeding of common spruce, European silver-fir, beech, sycamore maple, European mountainash, and grey alder was simulated by means of controlled sowing. For comparison, a greenhouse experiment was carried out, examining the germination and development of the same tree species in various soil substrata, using different fertilizers, and under the influence of artificial acid rain. The most important results - with a high level of variation depending on the tree species examined - can be summarized as follows: Based on the results of field and greenhouse experiments, as well as on the investigations of other authors, it can be concluded that natural regeneration of forest stands is considerably impeded under conditions of increasing soil acidity and by high acid depositions. This is seen directly as the result of unfavorable chemical conditions in the upper soil, as well as indirectly due to deteriorating competitiveness against other vegetation. Site preparation and lime or dolomite fertilization can be important measures in the practice of forestry, to encourage natural regeneration in highly acidic sites with an unfavourable humus layer and a high presence of competing vegetation. (orig./UWA). 2 figs., 85 tabs., 269 refs [de

  3. Hydroprocessing catalysts utilization and regeneration schemes

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.

    The catalyst reactor inventory represents an important part of the cost of hydroprocessing operation. The selection of a suitable catalyst and reactor is influenced by feedstock properties. Processes ensuring an uninterrupted operation during catalyst addition and withdrawal are preferred for processing high asphaltene and metal content feedstocks. The spent catalyst can be regenerated and returned to the operation if the extent of its deactivation is not high. The regeneration may be performed either in-situ or off-site. The former is suitable for fixed bed reactors whereas the catalyst from ebullated bed reactors must be regenerated off-site. The regeneration of spent catalysts heavily loaded with metals such as V, Ni and Fe may not be economic. Such catalysts may be suitable for metal reclamation. An environmentally safe method for catalyst disposal must be found if neither regeneration nor metal reclamation from spent catalysts can be performed.

  4. Regeneration limit of classical Shannon capacity

    Science.gov (United States)

    Sorokina, M. A.; Turitsyn, S. K.

    2014-05-01

    Since Shannon derived the seminal formula for the capacity of the additive linear white Gaussian noise channel, it has commonly been interpreted as the ultimate limit of error-free information transmission rate. However, the capacity above the corresponding linear channel limit can be achieved when noise is suppressed using nonlinear elements; that is, the regenerative function not available in linear systems. Regeneration is a fundamental concept that extends from biology to optical communications. All-optical regeneration of coherent signal has attracted particular attention. Surprisingly, the quantitative impact of regeneration on the Shannon capacity has remained unstudied. Here we propose a new method of designing regenerative transmission systems with capacity that is higher than the corresponding linear channel, and illustrate it by proposing application of the Fourier transform for efficient regeneration of multilevel multidimensional signals. The regenerative Shannon limit—the upper bound of regeneration efficiency—is derived.

  5. Composite cell sheet for periodontal regeneration: crosstalk between different types of MSCs in cell sheet facilitates complex periodontal-like tissue regeneration.

    Science.gov (United States)

    Zhang, Hao; Liu, Shiyu; Zhu, Bin; Xu, Qiu; Ding, Yin; Jin, Yan

    2016-11-14

    Tissue-engineering strategies based on mesenchymal stem cells (MSCs) and cell sheets have been widely used for periodontal tissue regeneration. However, given the complexity in periodontal structure, the regeneration methods using a single species of MSC could not fulfill the requirement for periodontal regeneration. We researched the interaction between the periodontal ligament stem cells (PDLSCs) and jaw bone marrow-derived mesenchymal stem cells (JBMMSCs), and constructed a composite cell sheet comprising both of the above MSCs to regenerate complex periodontium-like structures in nude mice. Our results show that by co-culturing PDLSCs and JBMMSCs, the expressions of bone and extracellular matrix (ECM)-related genes and proteins were significantly improved in both MSCs. Further investigations showed that, compared to the cell sheet using PDLSCs or JBMMSCs, the composite stem cell sheet (CSCS), which comprises these two MSCs, expressed higher levels of bone- and ECM-related genes and proteins, and generated a composite structure more similar to the native periodontal tissue physiologically in vivo. In conclusion, our results demonstrate that the crosstalk between PDLSCs and JBMMSCs in cell sheets facilitate regeneration of complex periodontium-like structures, providing a promising new strategy for physiological and functional regeneration of periodontal tissue.

  6. Romanian legal management rules limit wood production in Norway spruce and beech forests

    Directory of Open Access Journals (Sweden)

    Olivier Bouriaud

    2016-09-01

    Full Text Available Background The quantitative impact of forest management on forests’ wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m3.y-1 in regular mountain production forests, and to 15 million m3.y-1 if managed protection forest is included. Conclusions The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50

  7. A novel amniote model of epimorphic regeneration: the leopard gecko, Eublepharis macularius.

    Science.gov (United States)

    McLean, Katherine E; Vickaryous, Matthew K

    2011-08-16

    Epimorphic regeneration results in the restoration of lost tissues and structures from an aggregation of proliferating cells known as a blastema. Among amniotes the most striking example of epimorphic regeneration comes from tail regenerating lizards. Although tail regeneration is often studied in the context of ecological costs and benefits, details of the sequence of tissue-level events are lacking. Here we investigate the anatomical and histological events that characterize tail regeneration in the leopard gecko, Eublepharis macularius. Tail structure and tissue composition were examined at multiple days following tail loss, revealing a conserved pattern of regeneration. Removal of the tail results in a consistent series of morphological and histological events. Tail loss is followed by a latent period of wound healing with no visible signs of regenerative outgrowth. During this latent period basal cells of the epidermis proliferate and gradually cover the wound. An additional aggregation of proliferating cells accumulates adjacent to the distal tip of the severed spinal cord marking the first appearance of the blastema. Continued growth of the blastema is matched by the initiation of angiogenesis, followed by the re-development of peripheral axons and the ependymal tube of the spinal cord. Skeletal tissue differentiation, corresponding with the expression of Sox9, and muscle re-development are delayed until tail outgrowth is well underway. We demonstrate that tail regeneration in lizards involves a highly conserved sequence of events permitting the establishment of a staging table. We show that tail loss is followed by a latent period of scar-free healing of the wound site, and that regeneration is blastema-mediated. We conclude that the major events of epimorphic regeneration are highly conserved across vertebrates and that a comparative approach is an invaluable biomedical tool for ongoing regenerative research.

  8. Fostering and Planning Urban Regeneration

    DEFF Research Database (Denmark)

    Lidegaard, Christina; Nuccio, Massimiliano; Bille, Trine

    2018-01-01

    Policy-makers and urban planners struggle to find the right formula to implement urban regeneration processes based on cultural assets, often focusing on the desired outcomes, but rarely questioning how the policy process can shape them. This paper examines different governance models...... cultural districts in the city centre. The paper contributes to the literature on cultural districts by matching specificities and contingencies attached to a particular urban area with the governance model adopted for its development. The paper claims that temporal experimentation has to be included...... for the implementation and organization of cultural districts, and evaluates how they can affect their actual realization by investigating three cases in Copenhagen, Denmark. The deindustrialization of Copenhagen left many of the city’s harbour areas disused and in turn provided the opportunity to develop three new...

  9. Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub

    Science.gov (United States)

    Delerue, Florian; Gonzalez, Maya; Michalet, Richard; Pellerin, Sylvain; Augusto, Laurent

    2015-01-01

    The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation) due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development) as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se) and the physical world where the seedlings appear and develop (the regeneration habitat). PMID:26098877

  10. Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub.

    Directory of Open Access Journals (Sweden)

    Florian Delerue

    Full Text Available The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se and the physical world where the seedlings appear and develop (the regeneration habitat.

  11. A Tissue-Mapped Axolotl De Novo Transcriptome Enables Identification of Limb Regeneration Factors

    Directory of Open Access Journals (Sweden)

    Donald M. Bryant

    2017-01-01

    Full Text Available Mammals have extremely limited regenerative capabilities; however, axolotls are profoundly regenerative and can replace entire limbs. The mechanisms underlying limb regeneration remain poorly understood, partly because the enormous and incompletely sequenced genomes of axolotls have hindered the study of genes facilitating regeneration. We assembled and annotated a de novo transcriptome using RNA-sequencing profiles for a broad spectrum of tissues that is estimated to have near-complete sequence information for 88% of axolotl genes. We devised expression analyses that identified the axolotl orthologs of cirbp and kazald1 as highly expressed and enriched in blastemas. Using morpholino anti-sense oligonucleotides, we find evidence that cirbp plays a cytoprotective role during limb regeneration whereas manipulation of kazald1 expression disrupts regeneration. Our transcriptome and annotation resources greatly complement previous transcriptomic studies and will be a valuable resource for future research in regenerative biology.

  12. iTRAQ reveals proteomic changes during intestine regeneration in the sea cucumber Apostichopus japonicus.

    Science.gov (United States)

    Sun, Lina; Xu, Dongxue; Xu, Qinzeng; Sun, Jingchun; Xing, Lili; Zhang, Libin; Yang, Hongsheng

    2017-06-01

    Sea cucumbers have a striking capacity to regenerate most of their viscera after evisceration, which has drawn the interest of many researchers. In this study, the isobaric tag for relative and absolute quantitation (iTRAQ) was utilized to investigate protein abundance changes during intestine regeneration in sea cucumbers. A total of 4073 proteins were identified, and 2321 proteins exhibited significantly differential expressions, with 1100 upregulated and 1221 downregulated proteins. Our results suggest that intestine regeneration constitutes a complex life activity regulated by the cooperation of various biological processes, including cytoskeletal changes, extracellular matrix (ECM) remodeling and ECM-receptor interactions, protein synthesis, signal recognition and transduction, energy production and conversion, and substance transport and metabolism. Additionally, real-time PCR showed mRNA expression of differentially expressed genes correlated positively with their protein levels. Our results provided a basis for studying the regulatory mechanisms associated with sea cucumber regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The planarian flatworm: an in vivo model for stem cell biology and nervous system regeneration

    Directory of Open Access Journals (Sweden)

    Luca Gentile

    2011-01-01

    Full Text Available Planarian flatworms are an exception among bilaterians in that they possess a large pool of adult stem cells that enables them to promptly regenerate any part of their body, including the brain. Although known for two centuries for their remarkable regenerative capabilities, planarians have only recently emerged as an attractive model for studying regeneration and stem cell biology. This revival is due in part to the availability of a sequenced genome and the development of new technologies, such as RNA interference and next-generation sequencing, which facilitate studies of planarian regeneration at the molecular level. Here, we highlight why planarians are an exciting tool in the study of regeneration and its underlying stem cell biology in vivo, and discuss the potential promises and current limitations of this model organism for stem cell research and regenerative medicine.

  14. Economic efficiency of brownfield regeneration: study of South Moravian projects

    Directory of Open Access Journals (Sweden)

    Jana Korytárová

    2017-06-01

    Full Text Available The objective of brownfield regeneration is to increase the attractiveness and value of individual sites to a level where they can compete directly with the construction of a greenfi eld project. The aim of this paper is to examine the economic efficiency of brownfield regeneration. By using CBA outputs, the contribution of socio-economic efficiency to the total efficiency of individual projects based on EBCR was investigated on the basis of a sample of 14 projects located in the South Moravian Region. Furthermore, the expected value of EBCR was simulated by using the Monte Carlo method. The results reveal that socio-economic efficiency contributes significantly to the overall efficiency of these projects and therefore cannot be neglected during their evaluation. At the end of the paper, future research directions in this area are outlined.

  15. Extracellular matrix as a driver for lung regeneration.

    Science.gov (United States)

    Balestrini, Jenna L; Niklason, Laura E

    2015-03-01

    Extracellular matrix has manifold roles in tissue mechanics, guidance of cellular behavior, developmental biology, and regenerative medicine. Over the past several decades, various pre-clinical and clinical studies have shown that many connective tissues may be replaced and/or regenerated using suitable extracellular matrix scaffolds. More recently, decellularization of lung tissue has shown that gentle removal of cells can leave behind a "footprint" within the matrix that may guide cellular adhesion, differentiation and homing following cellular repopulation. Fundamental issues like understanding matrix composition and micro-mechanics remain difficult to tackle, largely because of a lack of available assays and tools for systematically characterizing intact matrix from tissues and organs. This review will critically examine the role of engineered and native extracellular matrix in tissue and lung regeneration, and provide insights into directions for future research and translation.

  16. Mesenchymal stem cells in cartilage regeneration.

    Science.gov (United States)

    Savkovic, Vuk; Li, Hanluo; Seon, Jong-Keun; Hacker, Michael; Franz, Sandra; Simon, Jan-Christoph

    2014-01-01

    Articular cartilage provides life-long weight-bearing and mechanical lubrication with extraordinary biomechanical performance and simple structure. However, articular cartilage is apparently vulnerable to multifactorial damage and insufficient to self-repair, isolated in articular capsule without nerves or blood vessels. Osteoarthritis (OA) is known as a degenerative articular cartilage deficiency progressively affecting large proportion of the world population, and restoration of hyaline cartilage is clinical challenge to repair articular cartilage lesion and recreate normal functionality over long period. Mesenchymal stem cells (MSC) are highly proliferative and multipotent somatic cells that are able to differentiate mesoderm-derived cells including chondrocytes and osteoblasts. Continuous endeavors in basic research and preclinical trial have achieved promising outcomes in cartilage regeneration using MSCs. This review focuses on rationale and technologies of MSC-based hyaline cartilage repair involving tissue engineering, 3D biomaterials and growth factors. By comparing conventional treatment and current research progress, we describe insights of advantage and challenge in translation and application of MSC-based chondrogenesis for OA treatment.

  17. Three-dimensional printing for craniomaxillofacial regeneration.

    Science.gov (United States)

    Gaviria, Laura; Pearson, Joseph J; Montelongo, Sergio A; Guda, Teja; Ong, Joo L

    2017-10-01

    Craniomaxillofacial injuries produce complex wound environments involving various tissue types and treatment strategies. In a clinical setting, care is taken to properly irrigate and stabilize the injury, while grafts are molded in an attempt to maintain physiological functionality and cosmesis. This often requires multiple surgeries and grafts leading to added discomfort, pain and financial burden. Many of these injuries can lead to disfigurement and resultant loss of system function including mastication, respiration, and articulation, and these can lead to acute and long-term psychological impact on the patient. A main causality of these issues is the lack of an ability to spatially control pre-injury morphology while maintaining shape and function. With the advent of additive manufacturing (three-dimensional printing) and its use in conjunction with biomaterial regenerative strategies and stem cell research, there is an increased potential capacity to alleviate such limitations. This review focuses on the current capabilities of additive manufacturing platforms, completed research and potential for future uses in the treatment of craniomaxillofacial injuries, with an in-depth discussion of regeneration of the periodontal complex and teeth.

  18. Pulp regeneration: Current approaches and future challenges

    Directory of Open Access Journals (Sweden)

    Jingwen eYANG

    2016-03-01

    Full Text Available Regenerative endodontics aims to replace inflamed/necrotic pulp tissues with regenerated pulp-like tissues to revitalize teeth and improve life quality. Pulp revascularization case reports, which showed successful clinical and radiographic outcomes, indicated the possible clinical application of pulp regeneration via cell homing strategy. From a clinical point of view, functional pulp-like tissues should be regenerated with the characterization of vascularization, re-innervation, and dentin deposition with a regulated rate similar to that of normal pulp. Efficient root canal disinfection and proper size of the apical foramen are the two requisite preconditions for pulp regeneration. Progress has been made on pulp regeneration via cell homing strategies. This review focused on the requisite preconditions and cell homing strategies for pulp regeneration. In addition to the traditionally used mechanical preparation and irrigation, antibiotics, irrigation assisted with EndoVac apical negative-pressure system, and ultrasonic and laser irradiation are now being used in root canal disinfection. In addition, pulp-like tissues could be formed with the apical foramen less than 1 mm, although more studies are needed to determine the appropriate size. Moreover, signaling molecules including stromal cell derived factor (SDF-1α, basic Fibroblast Growth Factor (bFGF, Platelet Derived Growth Factor (PDGF, stem cell factor (SCF, and Granulocyte Colony-Stimulating Factor (G-CSF were used to achieve pulp-like tissue formation via a cell homing strategy. Studies on the cell sources of pulp regeneration might give some indications on the signaling molecular selection. The active recruitment of endogenous cells into root canals to regenerate pulp-like tissues is a novel concept that may offer an unprecedented opportunity for the near-term clinical translation of current biology-based therapies for dental pulp regeneration.

  19. Ozone exposure, defoliation of beech (Fagus sylvatica L.) and visible foliar symptoms on native plants in selected plots of South-Western Europe

    International Nuclear Information System (INIS)

    Ferretti, Marco; Calderisi, Marco; Bussotti, Filippo

    2007-01-01

    The relationships between crown defoliation of beech, visible foliar symptoms on native vegetation and ozone exposure were investigated on permanent monitoring sites in South-Western Europe in the years 2000-2002. Relationships between defoliation of beech and O 3 (seasonal mean, 2-week maximum, AOT40) were investigated by means of multiple regression models (11 plots, 1-3 years of data each) and a model based on temporal autocorrelation of defoliation data (14 plots, 1-3 years of data each). Different multiple regression techniques were used. The four models generated (R 2 = 0.71-0.85, explained variance in cross-validation 61-78%) identified several significant predictors of defoliation, with AOT40 (p = 0.008) and foliar content of phosphorous (p = 0.0002-0.0004) being common to all models. The autocorrelation model (R 2 = 0.55; p 35,000 ppbh). O 3 -like visible foliar symptoms were recorded on 65 species at 47% of the common monitoring sites in 2001 and 38% in 2002. No relationship was found between O 3 exposure, frequency of symptomatic sites and frequency of species with symptoms (R 2 = 0.11; p > 0.05). A number of questions related to the ecological and methodological basis of the survey were identified. Inherent sampling and non-sampling errors and multicollinearity of the data suggest great caution when examining results obtained from mensurational, correlative studies. - Ozone AOT40 was identified as a significant predictor of defoliation of beech, but a limited relationship was found between ozone exposure and visible symptoms on native vegetation

  20. Aberrant regeneration of the third cranial nerve.

    Science.gov (United States)

    Shrestha, U D; Adhikari, S

    2012-01-01

    Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

  1. Patterns of mast fruiting of common beech, sessile and common oak, Norway spruce and Scots pine in Central and Northern Europe

    DEFF Research Database (Denmark)

    Nussbaumer, Anita; Waldner, Peter; Etzold, Sophia

    2016-01-01

    Occurrence of mast years, i.e. the synchronous production of vast amounts of fruits or seeds, has an important impact on forest ecosystems, their functioning and their services. We investigated the mast patterns of the forest tree species common beech, common and sessile oak, Norway spruce...... and Scots pine in Central and Northern Europe over the last two to three decades. We analysed data from the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and additional Danish, German, Flemish and Swiss datasets.Within-plot synchrony...

  2. Can decision rules simulate carbon allocation for years with contrasting and extreme weather conditions? A case study for three temperate beech forests

    DEFF Research Database (Denmark)

    Campioli, Matteo; Verbeeck, Hans; Van den Bossche, Joris

    2013-01-01

    The allocation of carbohydrates to different tree processes and organs is crucial to understand the overall carbon (C) cycling rate in forest ecosystems. Decision rules (DR) (e.g. functional balances and source-sink relationships) are widely used to model C allocation in forests. However, standard...... allocation and wood growth at beech stands with contrasting climate and standing stock. However, the allocation model required high quality GPP input and errors (even modest) in GPP resulted in large errors in the growth of the tree organs lowest in the modelled sink hierarchy (woody organs). The ability...

  3. Native lignin for bonding fiber boards - evaluation of bonding mechanisms in boards made from laccase-treated fibers of beech (Fagus sylvatica)

    DEFF Research Database (Denmark)

    Felby, Claus; Thygesen, Lisbeth Garbrecht; Sanadi, Anand

    2004-01-01

    indicate that lignin extractives are precipitated on the fiber surfaces. The improved bonding may be related to several factors, linked to a more lignin rich fiber surface, such as surface molecular entanglements and covalent bonding between fibers through cross-linking of radicals. (C) 2004 Published......The auto-adhesion of beech wood (Fagus sylvatica) fibers can be enhanced by a pretreatment of the fibers with a phenol oxidase enzyme. The mechanism of enzymatic catalyzed bonding is linked to the generation of stable radicals in lignin by oxidation. Fiberboards made from laccase-treated fibers...

  4. Changes in the enchytraeid fauna of a moder soil beech stand after liming. Veraenderungen der Enchytraeidenfauna in einem Sauerhumus-Buchenwald nach Bestandeskalkung

    Energy Technology Data Exchange (ETDEWEB)

    Schoch-Boesken, J. (Duesseldorf Univ. (Germany). 2. Zoologisches Inst.); Greven, H. (Duesseldorf Univ. (Germany). 2. Zoologisches Inst.)

    1989-01-01

    A survey of the enchytraeid fauna before and two years after liming of a beech forest and comparison with an untreated area (Luzulo-Fagetum) reveal changes in the number of individuals/m[sup 2], number of species. Shannon-Weaver-Index and Evenness, particularly when individual soil horizons are considered. These changes obviously are related to the elevated pH of the soil after liming. pH-preferences of enchytraeids, whose dominances are strongly affected by liming, are shown. (orig.)

  5. Particulate emissions from the combustion of birch, beech, and spruce logs cause different cytotoxic responses in A549 cells.

    Science.gov (United States)

    Kasurinen, Stefanie; Jalava, Pasi I; Happo, Mikko S; Sippula, Olli; Uski, Oskari; Koponen, Hanna; Orasche, Jürgen; Zimmermann, Ralf; Jokiniemi, Jorma; Hirvonen, Maija-Riitta

    2017-05-01

    According to the World Health Organization particulate emissions from the combustion of solid fuels caused more than 110,000 premature deaths worldwide in 2010. Log wood combustion is the most prevalent form of residential biomass heating in developed countries, but it is unknown how the type of wood logs used in furnaces influences the chemical composition of the particulate emissions and their toxicological potential. We burned logs of birch, beech and spruce, which are used commonly as firewood in Central and Northern Europe in a modern masonry heater, and compared them to the particulate emissions from an automated pellet boiler fired with softwood pellets. We determined the chemical composition (elements, ions, and carbonaceous compounds) of the particulate emissions with a diameter of less than 1 µm and tested their cytotoxicity, genotoxicity, inflammatory potential, and ability to induce oxidative stress in a human lung epithelial cell line. The chemical composition of the samples differed significantly, especially with regard to the carbonaceous and metal contents. Also the toxic effects in our tested endpoints varied considerably between each of the three log wood combustion samples, as well as between the log wood combustion samples and the pellet combustion sample. The difference in the toxicological potential of the samples in the various endpoints indicates the involvement of different pathways of toxicity depending on the chemical composition. All three emission samples from the log wood combustions were considerably more toxic in all endpoints than the emissions from the pellet combustion. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1487-1499, 2017. © 2016 Wiley Periodicals, Inc.

  6. Cytotoxic and genotoxic responses of human lung cells to combustion smoke particles of Miscanthus straw, softwood and beech wood chips

    Science.gov (United States)

    Arif, Ali Talib; Maschowski, Christoph; Garra, Patxi; Garcia-Käufer, Manuel; Petithory, Tatiana; Trouvé, Gwenaëlle; Dieterlen, Alain; Mersch-Sundermann, Volker; Khanaqa, Polla; Nazarenko, Irina; Gminski, Richard; Gieré, Reto

    2017-08-01

    Inhalation of particulate matter (PM) from residential biomass combustion is epidemiologically associated with cardiovascular and pulmonary diseases. This study investigates PM0.4-1 emissions from combustion of commercial Miscanthus straw (MS), softwood chips (SWC) and beech wood chips (BWC) in a domestic-scale boiler (40 kW). The PM0.4-1 emitted during combustion of the MS, SWC and BWC were characterized by ICP-MS/OES, XRD, SEM, TEM, and DLS. Cytotoxicity and genotoxicity in human alveolar epithelial A549 and human bronchial epithelial BEAS-2B cells were assessed by the WST-1 assay and the DNA-Alkaline Unwinding Assay (DAUA). PM0.4-1 uptake/translocation in cells was investigated with a new method developed using a confocal reflection microscope. SWC and BWC had a inherently higher residual water content than MS. The PM0.4-1 emitted during combustion of SWC and BWC exhibited higher levels of Polycyclic Aromatic Hydrocarbons (PAHs), a greater variety of mineral species and a higher heavy metal content than PM0.4-1 from MS combustion. Exposure to PM0.4-1 from combustion of SWC and BWC induced cytotoxic and genotoxic effects in human alveolar and bronchial cells, whereby the strongest effect was observed for BWC and was comparable to that caused by diesel PM (SRM 2 975), In contrast, PM0.4-1 from MS combustion did not induce cellular responses in the studied lung cells. A high PAH content in PM emissions seems to be a reliable chemical marker of both combustion efficiency and particle toxicity. Residual biomass water content strongly affects particulate emissions and their toxic potential. Therefore, to minimize the harmful effects of fine PM on health, improvement of combustion efficiency (aiming to reduce the presence of incomplete combustion products bound to PM) and application of fly ash capture technology, as well as use of novel biomass fuels like Miscanthus straw is recommended.

  7. Tests for attraction to prey and predator avoidance by chemical cues in spiders of the beech forest floor

    Directory of Open Access Journals (Sweden)

    Wetter, Melissa B.

    2012-07-01

    Full Text Available Spiders leave draglines, faeces and other secretions behind when traveling through their microhabitat. The presence of these secretions may unintentionally inform other animals, prey as well as predators, about a recent and possible current predation risk or food availability. For a wolf spider, other spiders including smaller conspecifics, form a substantial part of their prey, and larger wolf spiders, again including conspecifics, are potential predators. We tested two hypotheses: that large wolf spiders may locate patches of potential spider prey through the presence of silk threads and/or other secretions; and that prey spiders may use secretions from large wolf spiders to avoid patches with high predation risk. We used large (subadult or adult Pardosa saltans to provide predator cues and mixed dwarf spiders or small (juvenile P. saltans to provide prey cues. Subadult wolf spiders were significantly attracted to litter contaminated by dwarf spiders or small conspecifics after 6 hours but no longer after 24 hours. In contrast, neither dwarf spiders nor small P. saltans showed significant avoidance of substrate contaminated by adult P. saltans. However, small P. saltans showed different activity patterns on the two substrates. The results indicate that wolf spiders are able to increase the efficiency of foraging by searching preferentially in patches with the presence of intraguild prey. The lack of a clear patch selection response of the prey in spite of a modified activity pattern may possibly be associated with the vertical stratification of the beech litter habitat: the reduced volume of spaces in the deeper layers could make downward rather than horizontal movement a fast and safe tactic against a large predator that cannot enter these spaces.

  8. The impact of forest roads on understory plant diversity in temperate hornbeam-beech forests of Northern Iran.

    Science.gov (United States)

    Deljouei, Azade; Abdi, Ehsan; Marcantonio, Matteo; Majnounian, Baris; Amici, Valerio; Sohrabi, Hormoz

    2017-08-01

    Forest roads alter the biotic and abiotic components of ecosystems, modifying temperature, humidity, wind speed, and light availability that, in turn, cause changes in plant community composition and diversity. We aim at investigating and comparing the diversity of herbaceous species along main and secondary forest roads in a temperate-managed hornbeam-beech forest, north of Iran. Sixteen transects along main and secondary forest roads were established (eight transects along main roads and eight along secondary roads). To eliminate the effect of forest type, all transects were located in Carpinetum-Fagetum forests, the dominant forest type in the study area. The total length of each transect was 200 m (100 m toward up slope and 100 m toward down slope), and plots were established along it at different distances from road edge. The diversity of herbaceous plant species was calculated in each plot using Shannon-Wiener index, species richness, and Pielou's index. The results showed that diversity index decreased when distance from road edge increases. This decreasing trend continued up to 60 m from forest road margin, and after this threshold, the index slightly increased. Depending on the type of road (main or secondary) as well as cut or fill slopes, the area showing a statistical different plant composition and diversity measured through Shannon-Wiener, species richness, and Pielou's index is up to 10 m. The length depth of the road edge effect found in main and secondary forest roads was small, but it could have cumulative effects on forest microclimate and forest-associated biota at the island scale. Forest managers should account for the effect of road buildings on plant communities.

  9. Regenerating America: Meeting the Challenge of Building Local Economies.

    Science.gov (United States)

    Gabel, Medard; And Others

    The document includes five papers on the implications and applications of regeneration by the Regeneration Project, based in Emmaus, Pa. The first paper, "Regenerating America: Meeting the Challenge of Building Local Economies," (Medard Gabel) defines regeneration as economic recovery and growth, fostered by diversification within a…

  10. Overview 2004 of NASA Stirling-Convertor CFD-Model Development and Regenerator R&D Efforts

    Science.gov (United States)

    Tew, Roy C.; Dyson, Rodger W.; Wilson, Scott D.; Demko, Rikako

    2005-01-01

    This paper reports on accomplishments in 2004 in development of Stirling-convertor CFD model at NASA GRC and via a NASA grant, a Stirling regenerator-research effort being conducted via a NASA grant (a follow-on effort to an earlier DOE contract), and a regenerator-microfabrication contract for development of a "next-generation Stirling regenerator." Cleveland State University is the lead organization for all three grant/contractual efforts, with the University of Minnesota and Gedeor Associates as subcontractors. Also, the Stirling Technology Co. and Sunpower, Inc. are both involved in all three efforts, either as funded or unfunded participants. International Mezzo Technologies of Baton Rouge, LA is the regenerator fabricator for the regenerator-microfabrication contract. Results of the efforts in these three areas are summarized.

  11. Composite Matrix Regenerator for Stirling Engines

    Science.gov (United States)

    Knowles, Timothy R.

    1997-01-01

    This project concerns the design, fabrication and testing of carbon regenerators for use in Stirling power convertors. Radial fiber design with nonmetallic components offers a number of potential advantages over conventional steel regenerators: reduced conduction and pressure drop losses, and the capability for higher temperature, higher frequency operation. Diverse composite fabrication methods are explored and lessons learned are summarized. A pulsed single-blow test rig has been developed that has been used for generating thermal effectiveness data for different flow velocities. Carbon regenerators have been fabricated by carbon vapor infiltration of electroflocked preforms. Performance data in a small Stirling engine are obtained. Prototype regenerators designed for the BP-1000 power convertor were fabricated and delivered to NASA-Lewis.

  12. ADAPTATION OF REGENERANTS OF Vaccinium Corymbosum L

    African Journals Online (AJOL)

    Kutas

    2011-05-09

    May 9, 2011 ... Adaptation of regenerants of Vaccinium corymbosum ... functions of the sheet plants growing in an aseptic culture, in hothouses or open ground .... L. (Koralle) were preserved in alcohol-acetic acid (3:1). ..... and soil moisture.

  13. Chronological protein synthesis in regenerating rat liver.

    Science.gov (United States)

    He, Jinjun; Hao, Shuai; Zhang, Hao; Guo, Fuzheng; Huang, Lingyun; Xiao, Xueyuan; He, Dacheng

    2015-07-01

    Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, (35) S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through (35) S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5-5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Rapid plant regeneration of chrysanthemum (Chrysanthemum ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-04

    May 4, 2009 ... demand for chrysanthemum, it has become one of the first commercial targets for ... frequency of multiple shoot regeneration response was. 95 and 91%, for nodal ..... Dordrecht, The Netherlands, pp. 91-101. Prasad RN ...

  15. Grazing management that regenerates ecosystem function and ...

    African Journals Online (AJOL)

    Grazing management that regenerates ecosystem function and grazingland ... in ecosystem improvement, productivity, soil carbon and fertility, water-holding ... for sufficient time to produce resource improvement, sound animal production, and ...

  16. An experimental study of passive regenerator geometries

    DEFF Research Database (Denmark)

    Engelbrecht, Kurt; Nielsen, Kaspar Kirstein; Pryds, Nini

    2011-01-01

    Active magnetic regenerative (AMR) systems are being investigated because they represent a potentially attractive alternative to vapor compression technology. The performance of these systems is dependent on the heat transfer and pressure drop performance of the regenerator geometry. Therefore th...

  17. Fingernails Yield Clues to Limb Regeneration

    Science.gov (United States)

    ... it is involved in limb formation in mammalian embryonic development, as well as limb regeneration in amphibians. ... of the nail stem cells and the underlying layer of cells called the nail epithelium are left ...

  18. Optimization of regeneration and transformation parameters in ...

    African Journals Online (AJOL)

    PRECIOUS

    transformation and regeneration therefore optimization of these two factors is .... An analysis of variance was conducted using explants types x construct ... and significant differences between means were assessed by the. Tukey's test at 1 and ...

  19. A numerical analysis of a reciprocating Active Magnetic Regenerator with a parallel-plate regenerator geometry

    DEFF Research Database (Denmark)

    Petersen, Thomas Frank; Pryds, Nini; Smith, Anders

    2007-01-01

    We have developed a two-dimensional model of a reciprocating Active Magnetic Regenerator(AMR) with a regenerator made of parallel plates arranged in a stack configuration. The time dependent,two-dimensional model solves the Navier-Stokes equations for the heat transfer fluid and the coupled heat...... transfer equations for the regenerator and the fluid. The model is implemented using the Finite Element Method. The model can be used to study both transient and steady-state phenomena in the AMR for any ratio of regenerator to fluid heat capacity. Results on the AMR performance for different design...

  20. Urban renewal: strategies for high density residential suburbs regeneration

    Directory of Open Access Journals (Sweden)

    Andrea Boeri

    2012-10-01

    Full Text Available This article summarizes the main results of a research conducted by the University of Bologna, Department of Architecture, within the framework of the Research Program PRIN 2008, «Renovation, regeneration and valorisation of social housing settlements built in the suburban areas in the second half of last century». Once quantified the residential stock, a methodology for multidisciplinary analysis, applied to a specific case study (the district of Pilastro in Bologna, aimed at evaluating the different complementary aspects of building quality (social, functional, technical and environmental ones was developed with the objective of formulating strategies of intervention and models aimed at reducing the problems detected.

  1. Stem Cell Therapy in Wound Healing and Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2016-08-01

    a novel approach to many diseases. SUMMARY: Wound healing therapies continue to rapidly evolve, with advances in basic science and engineering research heralding the development of new therapies, as well as ways to modify existing treatments. Stem cell-based therapy is one of the most promising therapeutic concepts for wound healing. Advances in stem cell biology have enabled researchers and clinicians alike with access to cells capable of actively modulating the healing response.  KEYWORDS: wound healing, tissue regeneration, stem cells therapy

  2. Re-use of radio-thermoluminescent LiF without regeneration; Reemploi sans regeneration du LiF radiothermoluminescent

    Energy Technology Data Exchange (ETDEWEB)

    Portal, G; Francois, H; Blanchard, Ph [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    There is at the present time a rapid development of dosimetry techniques using thermoluminescence. Amongst the many substance actually in use, research laboratories generally employ lithium fluoride which is of particular interest for dosing {beta} radiation and low-energy X and {gamma} radiation. It might also be of use in radioprotection if its practical application were simpler. It has in effect unstable traps situated just below the surface which adversely affect the measurements if the material is not regenerated before each operation; this process considerably complicates the carrying out of measurements in the field of radioprotection. We have prepared a lithium fluoride giving unstable peaks which are less pronounced that those of the commercially available product and which can therefore be used without regeneration. In this report we compare the thermoluminescence curves for these two products. An analysis is given of the reasons for which this radio-thermoluminescent product has a stable luminescence curve and can be used almost one hundred times without being regenerated. We show that this quality can be retained when the LiF is used as a filler for teflon for applications in detectors. (authors) [French] On assiste a un developpement rapide des techniques de dosimetrie par thermoluminescence. Parmi les nombreux materiaux actuellement utilises, les laboratoires de recherche font generalement porter leur preference sur le fluorure de lithium qui est particulierement interessant pour la dosimetrie des rayonnements {beta} et des rayonnements X et {gamma} de faible energie. Ses qualites seraient egalement appreciees en radioprotection si sa mise en oeuvre etait plus simple. Il presente en effet des pieges instables situes a une faible profondeur qui alterent les mesures si l'on ne procede pas, avant chaque utilisation, a la regeneration du materiau, operation qui alourdit considerablement les mesures pratiquees en radioprotection. Nous avons prepare un

  3. Emdogain--periodontal regeneration based on biomimicry.

    Science.gov (United States)

    Gestrelius, S; Lyngstadaas, S P; Hammarström, L

    2000-06-01

    Biomimicry has been introduced as a term for innovations inspired by nature [1]. Such innovations may appear in almost every part of modern society. This review on the effects of enamel matrix proteins on the formation of cementum and the development of emdogain for regeneration of periodontal tissues lost due to periodontitis shows an example of biomimicry in dentistry. Findings from clinical and laboratory investigations are summarized and the biological basis for enamel matrix-induced periodontal regeneration is discussed.

  4. DIAGNOSTICS AND REGENERATION OF COMMON RAIL INJECTORS

    Directory of Open Access Journals (Sweden)

    Łukasz KONIECZNY

    2015-03-01

    Full Text Available The article presents the methodology of Common Rail injector diagnostic, regeneration and regulation with use of professional test stands. The EPS 815 machine can be used to test and repair all BOSCH injectors fully satisfying the producer requirements and standards. The article describes an example injector diagnosis with use of such test stand and additionally presents appropriate injector regeneration and encoding techniques

  5. Straight-Pore Microfilter with Efficient Regeneration

    Science.gov (United States)

    Liu, Han; LaConti, Anthony B.; McCallum. Thomas J.; Schmitt, Edwin W.

    2010-01-01

    A novel, high-efficiency gas particulate filter has precise particle size screening, low pressure drop, and a simple and fast regeneration process. The regeneration process, which requires minimal material and energy consumption, can be completely automated, and the filtration performance can be restored within a very short period of time. This filter is of a novel material composite that contains the support structure and a novel coating.

  6. Abiotic factors influencing tropical dry forests regeneration

    Directory of Open Access Journals (Sweden)

    Ceccon Eliane

    2006-01-01

    Full Text Available Tropical dry forests represent nearly half the tropical forests in the world and are the ecosystems registering the greatest deterioration from the anthropogenic exploitation of the land. This paper presents a review on the dynamics of tropical dry forests regeneration and the main abiotic factors influencing this regeneration, such as seasonal nature, soil fertility and humidity, and natural and anthropic disturbances. The main purpose is to clearly understand an important part of TDF succession dynamics.

  7. Protoplast formation and regeneration in Lactobacillus delbrueckii

    OpenAIRE

    Singhvi, Mamta; Joshi, Dipti; Gaikaiwari, Shalaka; Gokhale, Digambar V.

    2010-01-01

    Method for production and regeneration of Lactobacillus delbrueckii protoplasts are described. The protoplasts were obtained by treatment with a mixture of lysozyme and mutanolysin in protoplast buffer at pH 6.5 with different osmotic stabilizers. The protoplasts were regenerated on deMan, Rogosa and Sharpe (MRS) with various osmotic stabilizers. Maximum protoplast formation was obtained in protoplast buffer with sucrose as an osmotic stabilizer using a combination of lysozyme (1 mg/ml) and m...

  8. Continuous microwave regeneration apparatus for absorption media

    Science.gov (United States)

    Smith, Douglas D.

    1999-01-01

    A method and apparatus for continuously drying and regenerating ceramic beads for use in process gas moisture drying operations such as glove boxes. A microwave energy source is coupled to a process chamber to internally heat the ceramic beads and vaporize moisture contained therein. In a preferred embodiment, the moisture laden ceramic beads are conveyed toward the microwave source by a screw mechanism. The regenerated beads flow down outside of the screw mechanism and are available to absorb additional moisture.

  9. Fuel cell catholyte regenerating apparatus

    International Nuclear Information System (INIS)

    Struthers, R. C.

    1985-01-01

    A catholyte regenerating apparatus for a fuel cell having a cathode section containing a catholyte solution and wherein fuel cell reaction reduces the catholyte to gas and water. The apparatus includes means to conduct partically reduced water diluted catholyte from the fuel cell and means to conduct the gas from the fuel cell to a mixing means. An absorption tower containing a volume of gas absorbing liquid solvent receives the mixed together gas and diluted catholyte from the mixing means within the absorption column, the gas is absorbed by the solvent and the gas ladened solvent and diluted catholyte are commingled. A liquid transfer means conducts gas ladened commingled. A liquid transfer means conducts gas ladened commingled solvent and electrolyte from the absorption column to an air supply means wherein air is added and commingled therewith and a stoichiometric volume of oxygen from the air is absorbed thereby. A second liquid transfer means conducts the gas ladened commingled solvent and diluted catholyte into a catalyst column wherein the oxygen and gas react to reconstitute the catholyte from which the gas was generated wna wherein the reconstituted diluted catholyte is separated from the solvent. Recirculating means conducts the solvent from the catalyst column back into the absorption column and liquid conducting means conducts the reconstituted catholyte to a holding tank preparatory for catholyte to a holding tank preparatory for recirculation through the cathode section of the fuel cell

  10. Advances in plasma skin regeneration.

    Science.gov (United States)

    Foster, K Wade; Moy, Ronald L; Fincher, Edgar F

    2008-09-01

    Plasma skin regeneration (PSR) is a novel method of resurfacing that uses plasma energy to create a thermal effect on the skin. PSR is different from lasers, light sources, and ablative lasers in that it is not chromophore dependent and does not vaporize tissue, but leaves a layer of intact, desiccated epidermis that acts as a natural biologic dressing and promotes wound healing and rapid recovery. Histological studies performed on plasma resurfacing patients have confirmed continued collagen production, reduction of elastosis, and progressive skin rejuvenation beyond 1 year after treatment. PSR has received US Food and Drug Administration 510 (k) clearance for treatment of rhytides of the body, superficial skin lesions, actinic keratoses, viral papillomata, and seborrheic keratoses. PSR also has beneficial effects in the treatment of other conditions including dyschromias, photoaging, skin laxity, and acne scars. The safety profile of PSR is excellent, and there have been no reports of demarcation lines in perioral, periorbital, or jawline areas, as can sometimes be observed following CO2 resurfacing. PSR is effective in improving facial and periorbital rhytides and can be used on nonfacial sites, including the hands, neck, and chest. Numerous treatment protocols with variable energy settings allow for individualized treatments and provide the operator with fine control over the degree of injury and length of subsequent recovery time.

  11. Optimization of Regenerators for AMRR Systems

    Energy Technology Data Exchange (ETDEWEB)

    Nellis, Gregory [University of Wisconsin, Madison, WI (United States); Klein, Sanford [University of Wisconsin, Madison, WI (United States); Brey, William [University of Wisconsin, Madison, WI (United States); Moine, Alexandra [University of Wisconsin, Madison, WI (United States); Nielson, Kaspar [University of Wisconsin, Madison, WI (United States)

    2015-06-18

    Active Magnetic Regenerative Refrigeration (AMRR) systems have no direct global warming potential or ozone depletion potential and hold the potential for providing refrigeration with efficiencies that are equal to or greater than the vapor compression systems used today. The work carried out in this project has developed and improved modeling tools that can be used to optimize and evaluate the magnetocaloric materials and geometric structure of the regenerator beds required for AMRR Systems. There has been an explosion in the development of magnetocaloric materials for AMRR systems over the past few decades. The most attractive materials, based on the magnitude of the measured magnetocaloric effect, tend to also have large amounts of hysteresis. This project has provided for the first time a thermodynamically consistent method for evaluating these hysteretic materials in the context of an AMRR cycle. An additional, practical challenge that has been identified for AMRR systems is related to the participation of the regenerator wall in the cyclic process. The impact of housing heat capacity on both passive and active regenerative systems has been studied and clarified within this project. This report is divided into two parts corresponding to these two efforts. Part 1 describes the work related to modeling magnetic hysteresis while Part 2 discusses the modeling of the heat capacity of the housing. A key outcome of this project is the development of a publically available modeling tool that allows researchers to identify a truly optimal magnetocaloric refrigerant. Typically, the refrigeration potential of a magnetocaloric material is judged entirely based on the magnitude of the magnetocaloric effect and other properties of the material that are deemed unimportant. This project has shown that a material with a large magnetocaloric effect (as evidenced, for example, by a large adiabatic temperature change) may not be optimal when it is accompanied by a large hysteresis

  12. Hydrogel based cartilaginous tissue regeneration: recent insights and technologies.

    Science.gov (United States)

    Chuah, Yon Jin; Peck, Yvonne; Lau, Jia En Josias; Hee, Hwan Tak; Wang, Dong-An

    2017-03-28

    Hydrogels have been extensively employed as an attractive biomaterial to address numerous existing challenges in the fields of regenerative medicine and research because of their unique properties such as the capability to encapsulate cells, high water content, ease of modification, low toxicity, injectability, in situ spatial fit and biocompatibility. These inherent properties have created many opportunities for hydrogels as a scaffold or a cell/drug carrier in tissue regeneration, especially in the field of cartilaginous tissue such as articular cartilage and intervertebral discs. A concise overview of the anatomy/physiology of these cartilaginous tissues and their pathophysiology, epidemiology and existing clinical treatments will be briefly described. This review article will discuss the current state-of-the-art of various polymers and developing strategies that are explored in establishing different technologies for cartilaginous tissue regeneration. In particular, an innovative approach to generate scaffold-free cartilaginous tissue via a transient hydrogel scaffolding system for disease modeling to pre-clinical trials will be examined. Following that, the article reviews numerous hydrogel-based medical implants used in clinical treatment of osteoarthritis and degenerated discs. Last but not least, the challenges and future directions of hydrogel based medical implants in the regeneration of cartilaginous tissue are also discussed.

  13. Endogenous retinal neural stem cell reprogramming for neuronal regeneration

    Directory of Open Access Journals (Sweden)

    Romain Madelaine

    2017-01-01

    Full Text Available In humans, optic nerve injuries and associated neurodegenerative diseases are often followed by permanent vision loss. Consequently, an important challenge is to develop safe and effective methods to replace retinal neurons and thereby restore neuronal functions and vision. Identifying cellular and molecular mechanisms allowing to replace damaged neurons is a major goal for basic and translational research in regenerative medicine. Contrary to mammals, the zebrafish has the capacity to fully regenerate entire parts of the nervous system, including retina. This regenerative process depends on endogenous retinal neural stem cells, the Müller glial cells. Following injury, zebrafish Müller cells go back into cell cycle to proliferate and generate new neurons, while mammalian Müller cells undergo reactive gliosis. Recently, transcription factors and microRNAs have been identified to control the formation of new neurons derived from zebrafish and mammalian Müller cells, indicating that cellular reprogramming can be an efficient strategy to regenerate human retinal neurons. Here we discuss recent insights into the use of endogenous neural stem cell reprogramming for neuronal regeneration, differences between zebrafish and mammalian Müller cells, and the need to pursue the identification and characterization of new molecular factors with an instructive and potent function in order to develop theurapeutic strategies for eye diseases.

  14. Herbivore impact on beech in selected tree plantations in the Beskydy and Jeseniky Mountains

    Czech Academy of Sciences Publication Activity Database

    Suchomel, J.; Heroldová, Marta; Purchart, L.; Homolka, Miloslav

    2010-01-01

    Roč. 3, č. 2 (2010), s. 187-192 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : browsing on tree species * man-made plantations * red deer * roe deer * brown hare Subject RIV: GK - Forestry

  15. Limb Regeneration in Axolotl: Is It Superhealing?

    Directory of Open Access Journals (Sweden)

    Stéphane Roy

    2006-01-01

    Full Text Available The ability of axolotls to regenerate their limbs is almost legendary. In fact, urodeles such as the axolotl are the only vertebrates that can regenerate multiple structures like their limbs, jaws, tail, spinal cord, and skin (the list goes on throughout their lives. It is therefore surprising to realize, although we have known of their regenerative potential for over 200 years, how little we understand the mechanisms behind this achievement of adult tissue morphogenesis. Many observations can be drawn between regeneration and other disciplines such as development and wound healing. In this review, we present new developments in functional analysis that will help to address the role of specific genes during the process of regeneration. We also present an analysis of the resemblance between wound healing and regeneration, and discuss whether axolotls are superhealers. A better understanding of these animals' regenerative capacity could lead to major benefits by providing regenerative medicine with directions on how to develop therapeutic approaches leading to regeneration in humans.

  16. Silymarin Accelerates Liver Regeneration after Partial Hepatectomy

    Directory of Open Access Journals (Sweden)

    Jia-Ping Wu

    2015-01-01

    Full Text Available Partial hepatectomy (PHx is a liver regeneration physiological response induced to maintain homeostasis. Liver regeneration evolved presumably to protect wild animals from catastrophic liver loss caused by toxins or tissue injury. Silymarin (Sm ability to stimulate liver regeneration has been an object of curiosity for many years. Silymarin has been investigated for use as an antioxidant and anticarcinogen. However, its use as a supportive treatment for liver damage is elusive. In this study, we fed silymarin (Sm, 25 mg/kg to male Sprague-Dawley rats for 7 weeks. Surgical 2/3 PHx was then conducted on the rats at 6 hrs, 24 hrs, and 72 hrs. Western blot and RT-PCR were conducted to detect the cell cycle activities and silymarin effects on hepatic regeneration. The results showed that silymarin enhanced liver regeneration by accelerating the cell cycle in PHx liver. Silymarin led to increased G1 phase (cyclin D1/pRb, S phase (cyclin E/E2F, G2 phase (cyclin B, and M phase (cyclin A protein and mRNA at 6 hrs, 24 hrs, and 72 hrs PHx. HGF, TGFα, and TGFβ1 growth factor expressions were also enhanced. We suggest that silymarin plays a crucial role in accelerated liver regeneration after PHx.

  17. Bioengineered Lacrimal Gland Organ Regeneration in Vivo

    Directory of Open Access Journals (Sweden)

    Masatoshi Hirayama

    2015-07-01

    Full Text Available The lacrimal gland plays an important role in maintaining a homeostatic environment for healthy ocular surfaces via tear secretion. Dry eye disease, which is caused by lacrimal gland dysfunction, is one of the most prevalent eye disorders and causes ocular discomfort, significant visual disturbances, and a reduced quality of life. Current therapies for dry eye disease, including artificial tear eye drops, are transient and palliative. The lacrimal gland, which consists of acini, ducts, and myoepithelial cells, develops from its organ germ via reciprocal epithelial-mesenchymal interactions during embryogenesis. Lacrimal tissue stem cells have been identified for use in regenerative therapeutic approaches aimed at restoring lacrimal gland functions. Fully functional organ replacement, such as for tooth and hair follicles, has also been developed via a novel three-dimensional stem cell manipulation, designated the Organ Germ Method, as a next-generation regenerative medicine. Recently, we successfully developed fully functional bioengineered lacrimal gland replacements after transplanting a bioengineered organ germ using this method. This study represented a significant advance in potential lacrimal gland organ replacement as a novel regenerative therapy for dry eye disease. In this review, we will summarize recent progress in lacrimal regeneration research and the development of bioengineered lacrimal gland organ replacement therapy.

  18. Scaffold-free Prevascularized Microtissue Spheroids for Pulp Regeneration.

    Science.gov (United States)

    Dissanayaka, W L; Zhu, L; Hargreaves, K M; Jin, L; Zhang, C

    2014-12-01

    Creating an optimal microenvironment that mimics the extracellular matrix (ECM) of natural pulp and securing an adequate blood supply for the survival of cell transplants are major hurdles that need to be overcome in dental pulp regeneration. However, many currently available scaffolds fail to mimic essential functions of natural ECM. The present study investigated a novel approach involving the use of scaffold-free microtissue spheroids of dental pulp stem cells (DPSCs) prevascularized by human umbilical vein endothelial cells (HUVECs) in pulp regeneration. In vitro-fabricated microtissue spheroids were inserted into the canal space of tooth-root slices and were implanted subcutaneously into immunodeficient mice. Histological examination revealed that, after four-week implantation, tooth-root slices containing microtissue spheroids resulted in well-vascularized and cellular pulp-like tissues, compared with empty tooth-root slices, which were filled with only subcutaneous fat tissue. Immunohistochemical staining indicated that the tissue found in the tooth-root slices was of human origin, as characterized by the expression of human mitochondria, and contained odontoblast-like cells organized along the dentin, as assessed by immunostaining for nestin and dentin sialoprotein (DSP). Vascular structures formed by HUVECs in vitro were successfully anastomosed with the host vasculature upon transplantation in vivo, as shown by immunostaining for human CD31. Collectively, these findings demonstrate that prevascularized, scaffold-free, microtissue spheroids can successfully regenerate vascular dental pulp-like tissue and also highlight the significance of the microtissue microenvironment as an optimal environment for successful pulp-regeneration strategies. © International & American Associations for Dental Research.

  19. Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

    Science.gov (United States)

    Navarro, Xavier

    2016-02-01

    Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Natural regeneration in Iberian pines: A review of dynamic processes and proposals for management

    Directory of Open Access Journals (Sweden)

    Rafael Calama

    2017-10-01

    Full Text Available Aim of study: Designing adequate silvicultural systems for natural regeneration of a forest species requires sound knowledge of the underlying ecological subprocesses: flowering and fruiting, seed dispersal and predation, seed germination, seedling emergence and seedling survival. The main objective of the present work is to carry out a review on the current knowledge about the different subprocesses governing the regeneration process for the main Iberian Pinus species, in order to propose scientifically based management schedules. Area of study: The review focuses on the five main native Pinus species within their most representative areas in the Iberian Peninsula: Pinus nigra in Cuenca mountains, Pinus sylvestris in Sierra de Guadarrama, Pinus pinaster and Pinus pinea in the Northern Plateau and Pinus halepensis in Catalonia Material and methods: Firstly, currently available information on spatiotemporal dynamics and influential factors is introduced for each subprocess and species. Secondly, current regeneration strategies are characterized and the main bottlenecks are identified. Finally, alternative silvicultural practices proposed on the light of the previous information are presented. Main results: Different climate-mediated bottlenecks have been identified to limit natural regeneration of the Iberian pine species, with seed predation and initial seedling survival among the most influential. New approaches focusing on more gradual regeneration fellings, extended rotation periods, prevent big gaps and program fellings on mast years are presented. Research highlights: Natural regeneration of the studied species exhibit an intermittent temporal pattern, which should be aggravated under drier scenarios. More flexible management schedules should fulfil these limitations.

  1. Natural regeneration in Iberian pines: A review of dynamic processes and proposals for management

    Energy Technology Data Exchange (ETDEWEB)

    Calama, R.; Manso, R.; Lucas-Borja, M.E.; Espelta, J.M.; Piqué, M.; Bravo, F.; Peso, C. del; Pardos, M.

    2017-11-01

    Aim of study: Designing adequate silvicultural systems for natural regeneration of a forest species requires sound knowledge of the underlying ecological subprocesses: flowering and fruiting, seed dispersal and predation, seed germination, seedling emergence and seedling survival. The main objective of the present work is to carry out a review on the current knowledge about the different subprocesses governing the regeneration process for the main Iberian Pinus species, in order to propose scientifically based management schedules. Area of study: The review focuses on the five main native Pinus species within their most representative areas in the Iberian Peninsula: Pinus nigra in Cuenca mountains, Pinus sylvestris in Sierra de Guadarrama, Pinus pinaster and Pinus pinea in the Northern Plateau and Pinus halepensis in Catalonia Material and methods: Firstly, currently available information on spatiotemporal dynamics and influential factors is introduced for each subprocess and species. Secondly, current regeneration strategies are characterized and the main bottlenecks are identified. Finally, alternative silvicultural practices proposed on the light of the previous information are presented. Main results: Different climate-mediated bottlenecks have been identified to limit natural regeneration of the Iberian pine species, with seed predation and initial seedling survival among the most influential. New approaches focusing on more gradual regeneration fellings, extended rotation periods, prevent big gaps and program fellings on mast years are presented. Research highlights: Natural regeneration of the studied species exhibit an intermittent temporal pattern, which should be aggravated under drier scenarios. More flexible management schedules should fulfil these limitations.

  2. Natural regeneration in Iberian pines: A review of dynamic processes and proposals for management

    International Nuclear Information System (INIS)

    Calama, R.; Manso, R.; Lucas-Borja, M.E.; Espelta, J.M.; Piqué, M.; Bravo, F.; Peso, C. del; Pardos, M.

    2017-01-01

    Aim of study: Designing adequate silvicultural systems for natural regeneration of a forest species requires sound knowledge of the underlying ecological subprocesses: flowering and fruiting, seed dispersal and predation, seed germination, seedling emergence and seedling survival. The main objective of the present work is to carry out a review on the current knowledge about the different subprocesses governing the regeneration process for the main Iberian Pinus species, in order to propose scientifically based management schedules. Area of study: The review focuses on the five main native Pinus species within their most representative areas in the Iberian Peninsula: Pinus nigra in Cuenca mountains, Pinus sylvestris in Sierra de Guadarrama, Pinus pinaster and Pinus pinea in the Northern Plateau and Pinus halepensis in Catalonia Material and methods: Firstly, currently available information on spatiotemporal dynamics and influential factors is introduced for each subprocess and species. Secondly, current regeneration strategies are characterized and the main bottlenecks are identified. Finally, alternative silvicultural practices proposed on the light of the previous information are presented. Main results: Different climate-mediated bottlenecks have been identified to limit natural regeneration of the Iberian pine species, with seed predation and initial seedling survival among the most influential. New approaches focusing on more gradual regeneration fellings, extended rotation periods, prevent big gaps and program fellings on mast years are presented. Research highlights: Natural regeneration of the studied species exhibit an intermittent temporal pattern, which should be aggravated under drier scenarios. More flexible management schedules should fulfil these limitations.

  3. The cancer paradigms of mammalian regeneration: can mammals regenerate as amphibians?

    Science.gov (United States)

    Sarig, Rachel; Tzahor, Eldad

    2017-04-01

    Regeneration in mammals is restricted to distinct tissues and occurs mainly by expansion and maturation of resident stem cells. During regeneration, even subtle mutations in the proliferating cells may cause a detrimental effect by eliciting abnormal differentiation or malignant transformation. Indeed, cancer in mammals has been shown to arise through deregulation of stem cells maturation, which often leads to a differentiation block and cell transformation. In contrast, lower organisms such as amphibians retain a remarkable regenerative capacity in various organs, which occurs via de- and re-differentiation of mature cells. Interestingly, regenerating amphibian cells are highly resistant to oncogenic transformation. Therapeutic approaches to improve mammalian regeneration mainly include stem-cell transplantations; but, these have proved unsuccessful in non-regenerating organs such as the heart. A recently developed approach is to induce de-differentiation of mature cardiomyocytes using factors that trigger their re-entry into the cell cycle. This novel approach raises numerous questions regarding the balance between transformation and regeneration induced by de-differentiation of mature mammalian somatic cells. Can this balance be controlled artificially? Do de-differentiated cells acquire the protection mechanisms seen in regenerating cells of lower organisms? Is this model unique to the cardiac tissue, which rarely develops tumors? This review describes regeneration processes in both mammals and lower organisms and, particularly, the ability of regenerating cells to avoid transformation. By comparing the characteristics of mammalian embryonic and somatic cells, we discuss therapeutic strategies of using various cell populations for regeneration. Finally, we describe a novel cardiac regeneration approach and its implications for regenerative medicine. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email

  4. A Microfabricated Segmented-Involute-Foil Regenerator for Enhancing Reliability and Performance of Stirling Engines. Phase III Final Report for the Radioisotope Power Conversion Technology NRA

    Science.gov (United States)

    Ibrahim, Mounir B.; Gedeon, David; Wood, Gary; McLean, Jeffrey

    2009-01-01

    Under Phase III of NASA Research Announcement contract NAS3-03124, a prototype nickel segmented-involute-foil regenerator was microfabricated and tested in a Sunpower Frequency-Test-Bed (FTB) Stirling convertor. The team for this effort consisted of Cleveland State University, Gedeon Associates, Sunpower Inc. and International Mezzo Technologies. Testing in the FTB convertor produced about the same efficiency as testing with the original random-fiber regenerator. But the high thermal conductivity of the prototype nickel regenerator was responsible for a significant performance degradation. An efficiency improvement (by a 1.04 factor, according to computer predictions) could have been achieved if the regenerator was made from a low-conductivity material. Also, the FTB convertor was not reoptimized to take full advantage of the microfabricated regenerator s low flow resistance; thus, the efficiency would likely have been even higher had the FTB been completely reoptimized. This report discusses the regenerator microfabrication process, testing of the regenerator in the Stirling FTB convertor, and the supporting analysis. Results of the pre-test computational fluid dynamics (CFD) modeling of the effects of the regenerator-test-configuration diffusers (located at each end of the regenerator) are included. The report also includes recommendations for further development of involute-foil regenerators from a higher-temperature material than nickel.

  5. Modeling regeneration responses of big sagebrush (Artemisia tridentata) to abiotic conditions

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Ecosystems dominated by big sagebrush, Artemisia tridentata Nuttall (Asteraceae), which are the most widespread ecosystems in semiarid western North America, have been affected by land use practices and invasive species. Loss of big sagebrush and the decline of associated species, such as greater sage-grouse, are a concern to land managers and conservationists. However, big sagebrush regeneration remains difficult to achieve by restoration and reclamation efforts and there is no regeneration simulation model available. We present here the first process-based, daily time-step, simulation model to predict yearly big sagebrush regeneration including relevant germination and seedling responses to abiotic factors. We estimated values, uncertainty, and importance of 27 model parameters using a total of 1435 site-years of observation. Our model explained 74% of variability of number of years with successful regeneration at 46 sites. It also achieved 60% overall accuracy predicting yearly regeneration success/failure. Our results identify specific future research needed to improve our understanding of big sagebrush regeneration, including data at the subspecies level and improved parameter estimates for start of seed dispersal, modified wet thermal-time model of germination, and soil water potential influences. We found that relationships between big sagebrush regeneration and climate conditions were site specific, varying across the distribution of big sagebrush. This indicates that statistical models based on climate are unsuitable for understanding range-wide regeneration patterns or for assessing the potential consequences of changing climate on sagebrush regeneration and underscores the value of this process-based model. We used our model to predict potential regeneration across the range of sagebrush ecosystems in the western United States, which confirmed that seedling survival is a limiting factor, whereas germination is not. Our results also suggested that modeled

  6. Calcicolous beech forests and related vegetation in the Czech Republic: a comparison of formalized classifications

    Czech Academy of Sciences Publication Activity Database

    Boublík, Karel; Petřík, Petr; Sádlo, Jiří; Hédl, Radim; Willner, W.; Černý, Tomáš; Kolbek, Jiří

    2007-01-01

    Roč. 79, - (2007), s. 141-161 ISSN 0032-7786 R&D Projects: GA AV ČR IAA6005202; GA ČR(CZ) GA206/05/0020; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60050516 Keywords : Cephalanthero-Fagenion * Cocktail * formalized classification Subject RIV: EF - Botanics Impact factor: 2.064, year: 2007

  7. Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees

    International Nuclear Information System (INIS)

    Olbrich, Maren; Knappe, Claudia; Wenig, Marion; Gerstner, Elke; Haeberle, Karl-Heinz; Kitao, Mitsutoshi; Matyssek, Rainer; Stich, Susanne; Leuchner, Michael; Werner, Herbert; Schlink, Katja; Mueller-Starck, Gerhard; Welzl, Gerhard; Scherb, Hagen; Ernst, Dieter; Heller, Werner; Bahnweg, Guenther

    2010-01-01

    In 2006, a controlled infection study was performed in the 'Kranzberger Forst' to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2x ozone) and three control trees (ambient = 1x ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection. - Chronic sublethal ozone exposure reduces both natural and artificial infestation of beech leaves by the endophytic fungus Apiognomonia errabunda.

  8. Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees

    Energy Technology Data Exchange (ETDEWEB)

    Olbrich, Maren; Knappe, Claudia; Wenig, Marion; Gerstner, Elke [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Haeberle, Karl-Heinz; Kitao, Mitsutoshi; Matyssek, Rainer [Forest Botany, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Stich, Susanne [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Leuchner, Michael; Werner, Herbert [Bioclimatology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Schlink, Katja; Mueller-Starck, Gerhard [Section of Forest Genetics, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Welzl, Gerhard [Institute of Developmental Genetics, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Scherb, Hagen [Institute of Biomathematics and Biometry, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Ernst, Dieter; Heller, Werner [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Bahnweg, Guenther, E-mail: bahnweg@helmholtz-muenchen.d [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany)

    2010-04-15

    In 2006, a controlled infection study was performed in the 'Kranzberger Forst' to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2x ozone) and three control trees (ambient = 1x ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection. - Chronic sublethal ozone exposure reduces both natural and artificial infestation of beech leaves by the endophytic fungus Apiognomonia errabunda.

  9. Assessment of CH4 and N2O fluxes in a Danish Beech (Fagus sylvatica) forest and an adjacent N-fertilised barley (Hordeum vulgare)

    DEFF Research Database (Denmark)

    Ambus, P.; Jensen, J.M.; Prieme, A.

    2001-01-01

    Fluxes of CH4 and N2O were measured regularly in an agricultural field treated with 280 g m(-2) of sewage sludge. In a nearby beech forest N2O and CH4 fluxes were measured in a well-drained (dry) area and in a wet area adjacent to a drainage canal. We observed brief increases of both CH4 and N2O...... and independent of drainage status. Methane oxidation was observed all-year round in the forest cumulating to -225 mg C m(-2) and -84 mg C m(-2) in dry and wet areas. In a model experiment with incubated soil cores, nitrogen amendment (NH4Cl) and perturbation significantly reduced CH4 oxidation in the forest soil...... sludge, respectively. Four months after the sludge applications a significant effect on CO2 and NO emissions was still obvious in the field, the latter perhaps due to elevated nitrification. Nitrous oxide emission in the beech forest was about six times smaller (45 mg N m(-2)) than in the field...

  10. The influence of gap size on plant species diversity and composition in beech (Fagus orientalis forests, Ramsar, Mazandaran Province, North of Iran

    Directory of Open Access Journals (Sweden)

    MARZIEH BEGYOM-FAGHIR

    2013-10-01

    Full Text Available Pourbabaei H, Haddadi-Moghaddam H, Begyom-Faghir M, Abedi T. 2013. The influence of gap size on plant species diversity and composition in beech (Fagus orientalis forests, Ramsar, Mazandaran Province, North of Iran. Biodiversitas 14: 89-94.This study was conducted to investigate the influence of gap size on plant species diversity and composition in beech (Fagus orientalis Lipsky. forests, Ramsar, Mazandaran province. Fifteen gaps in small, medium, and large sizes were randomly selected. Abundance of tree saplings, shrubs and herbaceous species were counted on 4 m2 micro-plots within the gaps. Diversity indices including Shannon-Wiener, Simpson, Mc Arthur's N1, Hill's N2, species richness and Smith-Wilson’s evenness index were computed. The results revealed that there was significant difference among three gap categories in terms of diversity. The highest diversity values of tree and herbaceous species were obtained in the large gaps, while the highest diversity value of shrub species was in the medium gaps. Species composition of small gaps (28 species: 7 trees and 21 herbaceous, medium gaps (37 species: 7 trees, 5 shrubs and 25 herbaceous and large gaps (40 species: 7 trees, 4 shrubs and 29 herbaceous were recognized. Therefore, based on the results of this study, it is recommended that in order to maintain plant diversity and composition up to 400 m2 gap size cloud be used in this forests.

  11. Assessment of spatial discordance of primary and effective seed dispersal of European beech (Fagus sylvatica L.) by ecological and genetic methods.

    Science.gov (United States)

    Millerón, M; López de Heredia, U; Lorenzo, Z; Alonso, J; Dounavi, A; Gil, L; Nanos, N

    2013-03-01

    Spatial discordance between primary and effective dispersal in plant populations indicates that postdispersal processes erase the seed rain signal in recruitment patterns. Five different models were used to test the spatial concordance of the primary and effective dispersal patterns in a European beech (Fagus sylvatica) population from central Spain. An ecological method was based on classical inverse modelling (SSS), using the number of seed/seedlings as input data. Genetic models were based on direct kernel fitting of mother-to-offspring distances estimated by a parentage analysis or were spatially explicit models based on the genotype frequencies of offspring (competing sources model and Moran-Clark's Model). A fully integrated mixed model was based on inverse modelling, but used the number of genotypes as input data (gene shadow model). The potential sources of error and limitations of each seed dispersal estimation method are discussed. The mean dispersal distances for seeds and saplings estimated with these five methods were higher than those obtained by previous estimations for European beech forests. All the methods show strong discordance between primary and effective dispersal kernel parameters, and for dispersal directionality. While seed rain was released mostly under the canopy, saplings were established far from mother trees. This discordant pattern may be the result of the action of secondary dispersal by animals or density-dependent effects; that is, the Janzen-Connell effect. © 2013 Blackwell Publishing Ltd.

  12. Zirconia changes after grinding and regeneration firing.

    Science.gov (United States)

    Hatanaka, Gabriel R; Polli, Gabriela S; Fais, Laiza M G; Reis, José Maurício Dos S N; Pinelli, Lígia A P

    2017-07-01

    Despite improvements in computer-aided design and computer-aided manufacturing (CAD-CAM) systems, grinding during either laboratory procedures or clinical adjustments is often needed to modify the shape of 3 mol(%) yttria-tetragonal zirconia polycrystal (3Y-TZP) restorations. However, the best way to achieve adjustment is unclear. The purpose of this in vitro study was to evaluate the microstructural and crystallographic phase changes, flexural strength, and Weibull modulus of a 3Y-TZP zirconia after grinding with or without water cooling and regeneration firing. Ninety-six bar-shaped specimens were obtained and divided as follows: as-sintered, control; as-sintered with regeneration firing; grinding without water cooling; grinding and regeneration firing with water cooling; and grinding and regeneration firing. Grinding (0.3 mm) was performed with a 150-μm diamond rotary instrument in a high-speed handpiece. For regeneration firing, the specimens were annealed at 1000°C for 30 minutes. The crystalline phases were evaluated by using x-ray powder diffraction. A 4-point bending test was conducted (10 kN; 0.5 mm/min). The Weibull modulus was used to analyze strength reliability. The microstructure was analyzed by scanning electron microscopy. Data from the flexural strength test were evaluated using the Kruskal-Wallis and Dunn tests (α=.05). Tetragonal-to-monoclinic phase transformation was identified in the ground specimens; R regeneration firing groups showed only the tetragonal phase. The median flexural strength of as-sintered specimens was 642.0; 699.3 MPa for as-sintered specimens with regeneration firing; 770.1 MPa for grinding and water-cooled specimens; 727.3 MPa for specimens produced using water-cooled grinding and regeneration firing; 859.9 MPa for those produced by grinding; and 764.6 for those produced by grinding and regeneration firing; with statistically higher values for the ground groups. The regenerative firing did not affect the flexural

  13. Management of Stakeholders in Urban Regeneration Projects. Case Study: Baia-Mare, Transylvania

    Directory of Open Access Journals (Sweden)

    Corina M. Rădulescu

    2016-03-01

    Full Text Available The process of regeneration of abandoned areas or deteriorated structures in the cities of Romania has become a strategy of urban-integrated development. Conversions and/or regeneration of facilities in the form of assets, with different destinations, are part of the new trend of urban regeneration and a strategy used to attract investment capital. The disappearance of mining industry sites in Maramures County, Romania, has allowed the expansion and planning of new spaces for public use and/or semipublic, and most cities have opened new development perspectives. The study is based on empirical research conducted on the brownfields of Baia-Mare City. This research investigates how stakeholders of an urban regeneration project can be more actively involved in the decision-making processes with regard to the strategic elements of the renewal project of Cuprom, as a former mining industry area. This research contributes to the development of the investigation of new types of knowledge of stakeholder analysis and improves the available practices for stakeholder salience. Social networks created and consolidated by stakeholders of an urban regeneration project are the object of analysis, evaluation, and monitoring of the equilibrium between project management and grant of resources and capital. This paper studies the salience of stakeholders of the SEPA-CUPROM project from Baia-Mare using the social networking approach. Visualization by graphical methods of social networking analysis is a useful instrument in the decision-making process of brownfield projects as part of sustainable strategies in Romania.

  14. Functional hepatocellular regeneration measured by hepatobiliary scintigraphy, functional regeneration or functional hepatocytes?

    NARCIS (Netherlands)

    Olthof, Pim B.; Cieslak, Kasia P.; Bennink, Roelof J.; van Gulik, Thomas M.

    2016-01-01

    In a recent issue of this journal, Fernandes et al(1) reported on functional hepatocellular regeneration in elderly patients undergoing hepatectomy. They used (99m) Tc-mebrofinin HBS to quantify liver function before and after surgery and concluded that functional regeneration is already present at

  15. Regeneration in natural and logged tropical rain forest : modelling seed dispersal and regeneration

    NARCIS (Netherlands)

    Ulft, Lambertus Henricus van

    2004-01-01

    Regeneration and disturbance are thought to play key roles in the maintenance of the high tree species diversity in tropical rain forests. Nevertheless, the earliest stages in the regeneration of tropical rain forest trees, from seed production to established seedlings, have received little

  16. Applications of Metals for Bone Regeneration

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    Kristina Glenske

    2018-03-01

    Full Text Available The regeneration of bone tissue is the main purpose of most therapies in dental medicine. For bone regeneration, calcium phosphate (CaP-based substitute materials based on natural (allo- and xenografts and synthetic origins (alloplastic materials are applied for guiding the regeneration processes. The optimal bone substitute has to act as a substrate for bone ingrowth into a defect, as well as resorb in the time frame needed for complete regeneration up to the condition of restitution ad integrum. In this context, the modes of action of CaP-based substitute materials have been frequently investigated, where it has been shown that such materials strongly influence regenerative processes such as osteoblast growth or differentiation and also osteoclastic resorption due to different physicochemical properties of the materials. However, the material characteristics needed for the required ratio between new bone tissue formation and material degradation has not been found, until now. The addition of different substances such as collagen or growth factors and also of different cell types has already been tested but did not allow for sufficient or prompt application. Moreover, metals or metal ions are used differently as a basis or as supplement for different materials in the field of bone regeneration. Moreover, it has already been shown that different metal ions are integral components of bone tissue, playing functional roles in the physiological cellular environment as well as in the course of bone healing. The present review focuses on frequently used metals as integral parts of materials designed for bone regeneration, with the aim to provide an overview of currently existing knowledge about the effects of metals in the field of bone regeneration.

  17. Mechanisms of lymphatic regeneration after tissue transfer.

    Directory of Open Access Journals (Sweden)

    Alan Yan

    2011-02-01

    Full Text Available Lymphedema is the chronic swelling of an extremity that occurs commonly after lymph node resection for cancer treatment. Recent studies have demonstrated that transfer of healthy tissues can be used as a means of bypassing damaged lymphatics and ameliorating lymphedema. The purpose of these studies was to investigate the mechanisms that regulate lymphatic regeneration after tissue transfer.Nude mice (recipients underwent 2-mm tail skin excisions that were either left open or repaired with full-thickness skin grafts harvested from donor transgenic mice that expressed green fluorescent protein in all tissues or from LYVE-1 knockout mice. Lymphatic regeneration, expression of VEGF-C, macrophage infiltration, and potential for skin grafting to bypass damaged lymphatics were assessed.Skin grafts healed rapidly and restored lymphatic flow. Lymphatic regeneration occurred beginning at the peripheral edges of the graft, primarily from ingrowth of new lymphatic vessels originating from the recipient mouse. In addition, donor lymphatic vessels appeared to spontaneously re-anastomose with recipient vessels. Patterns of VEGF-C expression and macrophage infiltration were temporally and spatially associated with lymphatic regeneration. When compared to mice treated with excision only, there was a 4-fold decrease in tail volumes, 2.5-fold increase in lymphatic transport by lymphoscintigraphy, 40% decrease in dermal thickness, and 54% decrease in scar index in skin-grafted animals, indicating that tissue transfer could bypass damaged lymphatics and promote rapid lymphatic regeneration.Our studies suggest that lymphatic regeneration after tissue transfer occurs by ingrowth of lymphatic vessels and spontaneous re-connection of existing lymphatics. This process is temporally and spatially associated with VEGF-C expression and macrophage infiltration. Finally, tissue transfer can be used to bypass damaged lymphatics and promote rapid lymphatic regeneration.

  18. A Catskill Flora and Economic Botany, III: Apetalae. Including the Poplars, Willows, Hickories, Birches, Beeches, Oaks, Elms, Nettles, Sorrels, Docks, and Smartweeds. Bulletin No. 443, New York State Museum.

    Science.gov (United States)

    Brooks, Karl L.

    This compendium deals with the ecology and economic importance of the poplars, willows, hickories, birches, beeches, oaks, elms, nettles, sorrels, docks, and smartweeds growing in New York's Catskills. Provided are keys for identifying each plant to species by flowers, foliage, or winter buds. A line drawing accompanies a summary of basic data…

  19. Multi-scale processes of beech wood disintegration and pretreatment with 1-ethyl-3-methylimidazolium acetate/water mixtures.

    Science.gov (United States)

    Viell, Jörn; Inouye, Hideyo; Szekely, Noemi K; Frielinghaus, Henrich; Marks, Caroline; Wang, Yumei; Anders, Nico; Spiess, Antje C; Makowski, Lee

    2016-01-01

    The valorization of biomass for chemicals and fuels requires efficient pretreatment. One effective strategy involves the pretreatment with ionic liquids which enables enzymatic saccharification of wood within a few hours under mild conditions. This pretreatment strategy is, however, limited by water and the ionic liquids are rather expensive. The scarce understanding of the involved effects, however, challenges the design of alternative pretreatment concepts. This work investigates the multi length-scale effects of pretreatment of wood in 1-ethyl-3-methylimidazolium acetate (EMIMAc) in mixtures with water using spectroscopy, X-ray and neutron scattering. The structure of beech wood is disintegrated in EMIMAc/water mixtures with a water content up to 8.6 wt%. Above 10.7 wt%, the pretreated wood is not disintegrated, but still much better digested enzymatically compared to native wood. In both regimes, component analysis of the solid after pretreatment shows an extraction of few percent of lignin and hemicellulose. In concentrated EMIMAc, xylan is extracted more efficiently and lignin is defunctionalized. Corresponding to the disintegration at macroscopic scale, SANS and XRD show isotropy and a loss of crystallinity in the pretreated wood, but without distinct reflections of type II cellulose. Hence, the microfibril assembly is decrystallized into rather amorphous cellulose within the cell wall. The molecular and structural changes elucidate the processes of wood pretreatment in EMIMAc/water mixtures. In the aqueous regime with >10.7 wt% water in EMIMAc, xyloglucan and lignin moieties are extracted, which leads to coalescence of fibrillary cellulose structures. Dilute EMIMAc/water mixtures thus resemble established aqueous pretreatment concepts. In concentrated EMIMAc, the swelling due to decrystallinization of cellulose, dissolution of cross-linking xylan, and defunctionalization of lignin releases the mechanical stress to result in macroscopic disintegration of

  20. Temperature responses of growth and wood anatomy in European beech saplings grown in different carbon dioxide concentrations.

    Science.gov (United States)

    Overdieck, Dieter; Ziche, Daniel; Böttcher-Jungclaus, Kerstin

    2007-02-01

    Effects of temperature on growth and wood anatomy were studied in young European beech (Fagus sylvatica L.) grown in 7-l pots for 2.5 years in field-phytotron chambers supplied with an ambient (approximately 400 micromol mol-1) or elevated (approximately 700 micromol mol-1) carbon dioxide concentration ([CO2]). Temperatures in the chambers ranged in increments of 2 degrees C from -4 degrees C to +4 degrees C relative to the long-term mean monthly (day and night) air temperature in Berlin-Dahlem. Soil was not fertilized and soil water and air humidity were kept constant. Data were evaluated by regression analysis. At final harvest, stem diameter was significantly greater at increased temperature (Delta1 degrees C: 2.4%), stems were taller (Delta1 degrees C: 8.5%) and stem mass tree-1 (Delta1 degrees C: 10.9%) and leaf area tree-1(Delta1 degrees C: 6.5%) were greater. Allocation pattern was slightly influenced by temperature: leaf mass ratio and leaf area ratio decreased with increasing temperature (Delta1 degrees C: 2.3% and 2.2% respectively), whereas stem mass/total mass increased (Delta1 degrees C: 2.1%). Elevated [CO2] enhanced height growth by 8.8% and decreased coarse root mass/total mass by 10.3% and root/shoot ratio by 11.7%. Additional carbon was mainly invested in aboveground growth. At final harvest a synergistic interaction between elevated [CO2] and temperature yielded trees that were 3.2% taller at -4 degrees C and 12.7% taller at +4 degrees C than trees in ambient [CO2]. After 2.5 seasons, cross-sectional area of the oldest stem part was approximately 32% greater in the +4 degrees C treatment than in the -4 degrees C treatment, and in the last year approximately 67% more leaf area/unit tree ring area was produced in the highest temperature regime compared with the lowest. Elevated [CO2] decreased mean vessel area of the 120 largest vessels per mm2 by 5.8%, causing a decrease in water conducting capacity. There was a positive interaction between

  1. Temporal variability of the NPP-GPP ratio at seasonal and interannual time scales in a temperate beech forest

    Directory of Open Access Journals (Sweden)

    M. Campioli

    2011-09-01

    Full Text Available The allocation of carbon (C taken up by the tree canopy for respiration and production of tree organs with different construction and maintenance costs, life span and decomposition rate, crucially affects the residence time of C in forests and their C cycling rate. The carbon-use efficiency, or ratio between net primary production (NPP and gross primary production (GPP, represents a convenient way to analyse the C allocation at the stand level. In this study, we extend the current knowledge on the NPP-GPP ratio in forests by assessing the temporal variability of the NPP-GPP ratio at interannual (for 8 years and seasonal (for 1 year scales for a young temperate beech stand, reporting dynamics for both leaves and woody organs, in particular stems. NPP was determined with biometric methods/litter traps, whereas the GPP was estimated via the eddy covariance micrometeorological technique.

    The interannual variability of the proportion of C allocated to leaf NPP, wood NPP and leaf plus wood NPP (on average 11% yr−1, 29% yr−1 and 39% yr−1, respectively was significant among years with up to 12% yr−1 variation in NPP-GPP ratio. Studies focusing on the comparison of NPP-GPP ratio among forests and models using fixed allocation schemes should take into account the possibility of such relevant interannual variability. Multiple linear regressions indicated that the NPP-GPP ratio of leaves and wood significantly correlated with environmental conditions. Previous year drought and air temperature explained about half of the NPP-GPP variability of leaves and wood, respectively, whereas the NPP-GPP ratio was not decreased by severe drought, with large NPP-GPP ratio on 2003 due mainly to low GPP. During the period between early May and mid June, the majority of GPP was allocated to leaf and stem NPP, whereas these sinks were of little importance later on. Improved estimation of seasonal GPP and of the

  2. Lens regeneration in axolotl: new evidence of developmental plasticity

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    Suetsugu-Maki Rinako

    2012-12-01

    Full Text Available Abstract Background Among vertebrates lens regeneration is most pronounced in newts, which have the ability to regenerate the entire lens throughout their lives. Regeneration occurs from the dorsal iris by transdifferentiation of the pigment epithelial cells. Interestingly, the ventral iris never contributes to regeneration. Frogs have limited lens regeneration capacity elicited from the cornea during pre-metamorphic stages. The axolotl is another salamander which, like the newt, regenerates its limbs or its tail with the spinal cord, but up until now all reports have shown that it does not regenerate the lens. Results Here we present a detailed analysis during different stages of axolotl development, and we show that despite previous beliefs the axolotl does regenerate the lens, however, only during a limited time after hatching. We have found that starting at stage 44 (forelimb bud stage lens regeneration is possible for nearly two weeks. Regeneration occurs from the iris but, in contrast to the newt, regeneration can be elicited from either the dorsal or the ventral iris and, occasionally, even from both in the same eye. Similar studies in the zebra fish concluded that lens regeneration is not possible. Conclusions Regeneration of the lens is possible in the axolotl, but differs from both frogs and newts. Thus the axolotl iris provides a novel and more plastic strategy for lens regeneration.

  3. Redox Control of Skeletal Muscle Regeneration.

    Science.gov (United States)

    Le Moal, Emmeran; Pialoux, Vincent; Juban, Gaëtan; Groussard, Carole; Zouhal, Hassane; Chazaud, Bénédicte; Mounier, Rémi

    2017-08-10

    Skeletal muscle shows high plasticity in response to external demand. Moreover, adult skeletal muscle is capable of complete regeneration after injury, due to the properties of muscle stem cells (MuSCs), the satellite cells, which follow a tightly regulated myogenic program to generate both new myofibers and new MuSCs for further needs. Although reactive oxygen species (ROS) and reactive nitrogen species (RNS) have long been associated with skeletal muscle physiology, their implication in the cell and molecular processes at work during muscle regeneration is more recent. This review focuses on redox regulation during skeletal muscle regeneration. An overview of the basics of ROS/RNS and antioxidant chemistry and biology occurring in skeletal muscle is first provided. Then, the comprehensive knowledge on redox regulation of MuSCs and their surrounding cell partners (macrophages, endothelial cells) during skeletal muscle regeneration is presented in normal muscle and in specific physiological (exercise-induced muscle damage, aging) and pathological (muscular dystrophies) contexts. Recent advances in the comprehension of these processes has led to the development of therapeutic assays using antioxidant supplementation, which result in inconsistent efficiency, underlying the need for new tools that are aimed at precisely deciphering and targeting ROS networks. This review should provide an overall insight of the redox regulation of skeletal muscle regeneration while highlighting the limits of the use of nonspecific antioxidants to improve muscle function. Antioxid. Redox Signal. 27, 276-310.

  4. Method of continuously regenerating decontaminating electrolytic solution

    International Nuclear Information System (INIS)

    Sasaki, Takashi; Kobayashi, Toshio; Wada, Koichi.

    1985-01-01

    Purpose: To continuously recover radioactive metal ions from the electrolytic solution used for the electrolytic decontamination of radioactive equipment and increased with the radioactive dose, as well as regenerate the electrolytic solution to a high concentration acid. Method: A liquid in an auxiliary tank is recycled to a cathode chamber containing water of an electro depositing regeneration tank to render pH = 2 by way of a pH controller and a pH electrode. The electrolytic solution in an electrolytic decontaminating tank is introduced by way of an injection pump to an auxiliary tank and, interlocking therewith, a regenerating solution is introduced from a regenerating solution extracting pump by way of a extraction pipeway to an electrolytic decontaminating tank. Meanwhile, electric current is supplied to the electrode to deposit radioactive metal ions dissolved in the cathode chamber on the capturing electrode. While on the other hand, anions are transferred by way of a partition wall to an anode chamber to regenerate the electrolytic solution to high concentration acid solution. While on the other hand, water is supplied by way of an electromagnetic valve interlocking with the level meter to maintain the level meter constant. This can decrease the generation of the liquid wastes and also reduce the amount of the radioactive secondary wastes. (Horiuchi, T.)

  5. Planning and Implementation of Urban Regeneration

    DEFF Research Database (Denmark)

    Aunsborg, Christian; Sørensen, Michael Tophøj

    2008-01-01

    new statutory tools to handle the spatial transformation of urban regeneration areas. The paper examines the subsequent development of Danish planning legislation with the purpose of determining whether the present 'statutory toolbox' can be considered sufficient compared to the problems...... the regeneration challenge became an issue in the professional debate. The urban, economic and spatial problematics rising from structural development trends of society were subject to a committee work from 1999 through 2001. The work resulted in a number of recommendations comprising i.a. suggestions concerning...... and challenges emerging in practice. To evaluate the adequacy of the toolbox the paper draws on case studies on urban regeneration projects in three major Danish cities. The conclusion is that the legislative developments during the last five years must be considered very relevant to problem solving in practice...

  6. Demagnetizing fields in active magnetic regenerators

    DEFF Research Database (Denmark)

    Nielsen, Kaspar Kirstein; Bahl, Christian R.H.; Smith, Anders

    2014-01-01

    A magnetic material in an externally applied magnetic field will in general experience a spatially varying internal magnetic field due to demagnetizing effects. When the performance of active magnetic regenerators (AMRs) is evaluated using numerical models the internal field is often assumed...... is in general both a function of the overall shape of the regenerator and its morphology (packed particles, parallel plates etc.) as well as the magnetization of the material. Due to the pronounced temperature dependence of the magnetization near the Curie temperature, the demagnetization field is also...... temperature dependent. We propose a relatively straightforward method to correct sufficiently for the demagnetizing field in AMR models. We discuss how the demagnetizing field behaves in regenerators made of packed spheres under realistic operation conditions....

  7. Regeneration of neural crest derivatives in the Xenopus tadpole tail

    Directory of Open Access Journals (Sweden)

    Slack Jonathan MW

    2007-05-01

    Full Text Available Abstract Background After amputation of the Xenopus tadpole tail, a functionally competent new tail is regenerated. It contains spinal cord, notochord and muscle, each of which has previously been shown to derive from the corresponding tissue in the stump. The regeneration of the neural crest derivatives has not previously been examined and is described in this paper. Results Labelling of the spinal cord by electroporation, or by orthotopic grafting of transgenic tissue expressing GFP, shows that no cells emigrate from the spinal cord in the course of regeneration. There is very limited regeneration of the spinal ganglia, but new neurons as well as fibre tracts do appear in the regenerated spinal cord and the regenerated tail also contains abundant peripheral innervation. The regenerated tail contains a normal density of melanophores. Cell labelling experiments show that melanophores do not arise from the spinal cord during regeneration, nor from the mesenchymal tissues of the skin, but they do arise by activation and proliferation of pre-existing melanophore precursors. If tails are prepared lacking melanophores, then the regenerates also lack them. Conclusion On regeneration there is no induction of a new neural crest similar to that seen in embryonic development. However there is some regeneration of neural crest derivatives. Abundant melanophores are regenerated from unpigmented precursors, and, although spinal ganglia are not regenerated, sufficient sensory systems are produced to enable essential functions to continue.

  8. New insight into regenerated air heat pump cycle

    International Nuclear Information System (INIS)

    Zhang, Chun-Lu; Yuan, Han; Cao, Xiang

    2015-01-01

    Regenerated air (reverse Brayton) cycle has unique potentials in heat pump applications compared to conventional vapor-compression cycles. To better understand the regenerated air heat pump cycle characteristics, a thermodynamic model with new equivalent parameters was developed in this paper. Equivalent temperature ratio and equivalent isentropic efficiency of expander were introduced to represent the effect of regenerator, which made the regenerated air cycle in the same mathematical expressions as the basic air cycle and created an easy way to prove some important features that regenerated air cycle inherits from the basic one. Moreover, we proved in theory that the regenerator does not always improve the air cycle efficiency. Larger temperature ratio and lower effectiveness of regenerator could make the regenerated air cycle even worse than the basic air cycle. Lastly, we found that only under certain conditions the cycle could get remarkable benefits from a well-sized regenerator. These results would enable further study of the regenerated air cycle from a different perspective. - Highlights: • A thermodynamic model for regenerated air heat pump cycle was developed. • Equivalent temperature ratio and equivalent expander efficiency were introduced. • We proved regenerated air cycle can make heating capacity in line with heating load. • We proved the regenerator does not always improve the air cycle efficiency.

  9. Fibroblast growth factors as tissue repair and regeneration therapeutics

    Directory of Open Access Journals (Sweden)

    Quentin M. Nunes

    2016-01-01

    Full Text Available Cell communication is central to the integration of cell function required for the development and homeostasis of multicellular animals. Proteins are an important currency of cell communication, acting locally (auto-, juxta-, or paracrine or systemically (endocrine. The fibroblast growth factor (FGF family contributes to the regulation of virtually all aspects of development and organogenesis, and after birth to tissue maintenance, as well as particular aspects of organism physiology. In the West, oncology has been the focus of translation of FGF research, whereas in China and to an extent Japan a major focus has been to use FGFs in repair and regeneration settings. These differences have their roots in research history and aims. The Chinese drive into biotechnology and the delivery of engineered clinical grade FGFs by a major Chinese research group were important enablers in this respect. The Chinese language clinical literature is not widely accessible. To put this into context, we provide the essential molecular and functional background to the FGF communication system covering FGF ligands, the heparan sulfate and Klotho co-receptors and FGF receptor (FGFR tyrosine kinases. We then summarise a selection of clinical reports that demonstrate the efficacy of engineered recombinant FGF ligands in treating a wide range of conditions that require tissue repair/regeneration. Alongside, the functional reasons why application of exogenous FGF ligands does not lead to cancers are described. Together, this highlights that the FGF ligands represent a major opportunity for clinical translation that has been largely overlooked in the West.

  10. The TMI regenerable solid oxide fuel cell

    Science.gov (United States)

    Cable, Thomas L.

    1995-04-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC

  11. Ozone exposure, defoliation of beech (Fagus sylvatica L.) and visible foliar symptoms on native plants in selected plots of South-Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Ferretti, Marco [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: m.ferretti@linnaea.it; Calderisi, Marco [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: calderisi@chemiometria.it; Bussotti, Filippo [Dipartimento di Biologia Vegetale, Universita di Firenze, Piazzale Cascine 28, I-50144 Florence (Italy)]. E-mail: filippo.bussotti@unifi.it

    2007-02-15

    The relationships between crown defoliation of beech, visible foliar symptoms on native vegetation and ozone exposure were investigated on permanent monitoring sites in South-Western Europe in the years 2000-2002. Relationships between defoliation of beech and O{sub 3} (seasonal mean, 2-week maximum, AOT40) were investigated by means of multiple regression models (11 plots, 1-3 years of data each) and a model based on temporal autocorrelation of defoliation data (14 plots, 1-3 years of data each). Different multiple regression techniques were used. The four models generated (R {sup 2} = 0.71-0.85, explained variance in cross-validation 61-78%) identified several significant predictors of defoliation, with AOT40 (p = 0.008) and foliar content of phosphorous (p = 0.0002-0.0004) being common to all models. The autocorrelation model (R {sup 2} = 0.55; p < 0.0001) was used to calculate expected defoliation on the basis of the previous year's defoliation, and model predictions were used as an estimate of expected defoliation under constant site and environmental condition. Residuals (predicted-measured) plotted against current AOT40 shows that a possible effect of ozone occurs only at very high AOT40 (>35,000 ppbh). O{sub 3}-like visible foliar symptoms were recorded on 65 species at 47% of the common monitoring sites in 2001 and 38% in 2002. No relationship was found between O{sub 3} exposure, frequency of symptomatic sites and frequency of species with symptoms (R {sup 2} = 0.11; p > 0.05). A number of questions related to the ecological and methodological basis of the survey were identified. Inherent sampling and non-sampling errors and multicollinearity of the data suggest great caution when examining results obtained from mensurational, correlative studies. - Ozone AOT40 was identified as a significant predictor of defoliation of beech, but a limited relationship was found between ozone exposure and visible symptoms on native vegetation.

  12. Optimization for zeolite regeneration and nitrogen removal performance of a hypochlorite-chloride regenerant.

    Science.gov (United States)

    Zhang, Wei; Zhou, Zhen; An, Ying; Du, Silu; Ruan, Danian; Zhao, Chengyue; Ren, Ning; Tian, Xiaoce

    2017-07-01

    Simultaneous zeolites regeneration and nitrogen removal were investigated by using a mixed solution of NaClO and NaCl (NaClO-NaCl solution), and effects of the regenerant on ammonium removal performance and textural properties of zeolites were analyzed by long-term adsorption and regeneration operations. Mixed NaClO-NaCl solution removed more NH 4 + exchanged on zeolites and converted more of them to nitrogen than using NaClO or NaCl solution alone. Response surface methodological analysis indicated that molar ratio of hypochlorite and nitrogen (ClO - /N), NaCl concentration and pH value all had significant effects on zeolites regeneration and NH 4 + conversion to nitrogen, and the optimum condition was obtained at ClO - /N of 1.75, NaCl concentration of 20 g/L and pH of 10.0. Zeolites regenerated by mixed NaClO-NaCl solution showed higher ammonium adsorption rate and lower capacity than unused zeolites. Zeolites and the regeneration solution were both effective even after 20 cycles of use. Composition and morphological analysis revealed that the main mineral species and surface morphology of zeolites before and after NaClO-NaCl regeneration were unchanged. Textural analysis indicated that NaClO-NaCl regeneration leads to an increased surface area of zeolites, especially the microporosity. The results indicated that NaClO-NaCl regeneration is an attractive method to achieve sustainable removal of nitrogen from wastewater through zeolite. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Hydride heat pump with heat regenerator

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative hydride heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system. A series of at least four canisters containing a lower temperature performing hydride and a series of at least four canisters containing a higher temperature performing hydride is provided. Each canister contains a heat conductive passageway through which a heat transfer fluid is circulated so that sensible heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  14. Concept development of exchange liquid regeneration

    International Nuclear Information System (INIS)

    Mader, D.L.

    1985-08-01

    Concepts are described for regeneration of the intermediate liquid used for isotope exchange in indirect laser isotope separation processes where the laser operates on a process gas distinct from the feed stream. The specific case of regeneration of an exchange liquid consisting of water, sodium hydroxide, and dimethyl sulfoxide for a process to separate deuterium from hydrogen using laser irradiation of trifluoromethane gas is developed. A water feed stream is converted to steam which rises in a chemical process column where it redeuterates a descending flow of exchange liquid without causing significant changes in its chemical composition

  15. Regeneration of sulfated metal oxides and carbonates

    Science.gov (United States)

    Hubble, Bill R.; Siegel, Stanley; Cunningham, Paul T.

    1978-03-28

    Alkali metal or alkaline earth metal carbonates such as calcium carbonate and magnesium carbonate found in dolomite or limestone are employed for removal of sulfur dioxide from combustion exhaust gases. The sulfated carbonates are regenerated to oxides through use of a solid-solid reaction, particularly calcium sulfide with calcium sulfate to form calcium oxide and sulfur dioxide gas. The regeneration is performed by contacting the sulfated material with a reductant gas such as hydrogen within an inert diluent to produce calcium sulfide in mixture with the sulfate under process conditions selected to permit the sulfide-sulfate, solid-state reaction to occur.

  16. Identification of adequate vehicles to carry nerve regeneration inducers using tubulisation

    Directory of Open Access Journals (Sweden)

    do Nascimento-Elias Adriana Helena

    2012-08-01

    Full Text Available Abstract Background Axonal regeneration depends on many factors, such as the type of injury and repair, age, distance from the cell body and distance of the denervated muscle, loss of surrounding tissue and the type of injured nerve. Experimental models use tubulisation with a silicone tube to research regenerative factors and substances to induce regeneration. Agarose, collagen and DMEM (Dulbecco’s modified Eagle’s medium can be used as vehicles. In this study, we compared the ability of these vehicles to induce rat sciatic nerve regeneration with the intent of finding the least active or inert substance. The experiment used 47 female Wistar rats, which were divided into four experimental groups (agarose 4%, agarose 0.4%, collagen, DMEM and one normal control group. The right sciatic nerve was exposed, and an incision was made that created a 10 mm gap between the distal and proximal stumps. A silicone tube was grafted onto each stump, and the tubes were filled with the respective media. After 70 days, the sciatic nerve was removed. We evaluated the formation of a regeneration cable, nerve fibre growth, and the functional viability of the regenerated fibres. Results Comparison among the three vehicles showed that 0.4% agarose gels had almost no effect on provoking the regeneration of peripheral nerves and that 4% agarose gels completely prevented fibre growth. The others substances were associated with profuse nerve fibre growth. Conclusions In the appropriate concentration, agarose gel may be an important vehicle for testing factors that induce regeneration without interfering with nerve growth.

  17. An improved protocol for efficient transformation and regeneration of diverse indica rice cultivars

    Directory of Open Access Journals (Sweden)

    Sahoo Khirod K

    2011-12-01

    Full Text Available Abstract Background Rice genome sequencing projects have generated remarkable amount of information about genes and genome architecture having tremendous potential to be utilized in both basic and applied research. Success in transgenics is paving the way for preparing a road map of functional genomics which is expected to correlate action of a gene to a trait in cellular and organismal context. However, the lack of a simple and efficient method for transformation and regeneration is a major constraint for such studies in this important cereal crop. Results In the present study, we have developed an easy, rapid and highly efficient transformation and regeneration protocol using mature seeds as explants and found its successful applicability to a choice of elite indica rice genotypes. We have optimized various steps of transformation and standardized different components of the regeneration medium including growth hormones and the gelling agent. The modified regeneration medium triggers production of large number of shoots from smaller number of calli and promotes their faster growth, hence significantly advantageous over the existing protocols where the regeneration step requires maximum time. Using this protocol, significantly higher transformation efficiency (up to 46% and regeneration frequency (up to 92% for the untransformed calli and 59% for the transformed calli were achieved for the four tested cultivars. We have used this protocol to produce hundreds of independent transgenic lines of different indica rice genotypes. Upon maturity, these transgenic lines were fertile thereby indicating that faster regeneration during tissue culture did not affect their reproductive potential. Conclusions This speedy, yet less labor-intensive, protocol overcomes major limitations associated with genetic manipulation in rice. Moreover, our protocol uses mature seeds as the explant, which can easily be obtained in quantity throughout the year and kept

  18. Spontaneous hair cell regeneration in the mouse utricle following gentamicin ototoxicity.

    Science.gov (United States)

    Kawamoto, Kohei; Izumikawa, Masahiko; Beyer, Lisa A; Atkin, Graham M; Raphael, Yehoash

    2009-01-01

    Whereas most epithelial tissues turn-over and regenerate after a traumatic lesion, this restorative ability is diminished in the sensory epithelia of the inner ear; it is absent in the cochlea and exists only in a limited capacity in the vestibular epithelium. The extent of regeneration in vestibular hair cells has been characterized for several mammalian species including guinea pig, rat, and chinchilla, but not yet in mouse. As the fundamental model species for investigating hereditary disease, the mouse can be studied using a wide variety of genetic and molecular tools. To design a mouse model for vestibular hair cell regeneration research, an aminoglycoside-induced method of complete hair cell elimination was developed in our lab and applied to the murine utricle. Loss of utricular hair cells was observed using scanning electron microscopy, and corroborated by a loss of fluorescent signal in utricles from transgenic mice with GFP-positive hair cells. Regenerative capability was characterized at several time points up to six months following insult. Using scanning electron microscopy, we observed that as early as two weeks after insult, a few immature hair cells, demonstrating the characteristic immature morphology indicative of regeneration, could be seen in the utricle. As time progressed, larger numbers of immature hair cells could be seen along with some mature cells resembling surface morphology of type II hair cells. By six months post-lesion, numerous regenerated hair cells were present in the utricle, however, neither their number nor their appearance was normal. A BrdU assay suggested that at least some of the regeneration of mouse vestibular hair cells involved mitosis. Our results demonstrate that the vestibular sensory epithelium in mice can spontaneously regenerate, elucidate the time course of this process, and identify involvement of mitosis in some cases. These data establish a road map of the murine vestibular regenerative process, which can be

  19. Evaluation of the chitosan/glycerol-β-phosphate disodium salt hydrogel application in peripheral nerve regeneration

    International Nuclear Information System (INIS)

    Zheng Lu; Zhang Xiufang; Gong Yandao; Ao Qiang; Han Hongyan

    2010-01-01

    Research efforts have been devoted to evaluating the application of the chitosan (CS)/glycerol-β-phosphate (GP) disodium salt hydrogel in peripheral nerve regeneration. The gelation time was determined to be 770 s using ultraviolet spectrophotometry. A standard 10 mm long rat sciatic nerve defect model was employed, followed by bridging the proximal and distal stumps with chitosan conduits injected with the Schwann cell-containing hydrogel. Injections of the blank hydrogel, Schwann cell suspension and culture medium were used as controls. Two months later, electrophysiological assessment and fluorogold retrograde tracing showed that compound muscle action potentials (CMAPs) and fluorogold-labeled neurons were only detected in the Schwann cell suspension group and culture medium group. The rats were then killed, and implanted conduits were removed for examination. There were no regenerated nerves found in groups injected with the blank hydrogel or Schwann cell-containing hydrogel, while the other two groups clearly displayed regenerated nerves across the gaps. In the subsequent histological assessment, immunohistochemistry, toluidine blue staining and transmission electron microscopy were performed to evaluate the regenerated nerves. The relative wet weight ratio, Masson trichrome staining and acetylcholinesterase staining were employed for the examination of gastrocnemius muscles in all four groups. The Schwann cell suspension group showed the best results for all these indexes; the culture medium group ranked second and the two hydrogel-injected groups showed the least optimal results. In conclusion, our data revealed that the implanted CS/GP hydrogel actually impeded nerve regeneration, which is inconsistent with former in vitro reports and general supposition. We believe that the application of the CS/GP hydrogel in nerve regeneration requires a further study before a satisfactory result is obtained. In addition, the present study also confirmed that Schwann

  20. Factors influencing callus induction and plant regeneration of ...

    African Journals Online (AJOL)

    ajl yemi

    2012-01-12

    ). Effect of basal medium on callus induction and plant regeneration. Three different kinds of basal mediums (MS, N6 and SH) were used to investigate their effects on callus induction and regeneration. Significant differences ...