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Sample records for birches

  1. Winter Birch Trees

    Science.gov (United States)

    Sweeney, Debra; Rounds, Judy

    2011-01-01

    Trees are great inspiration for artists. Many art teachers find themselves inspired and maybe somewhat obsessed with the natural beauty and elegance of the lofty tree, and how it changes through the seasons. One such tree that grows in several regions and always looks magnificent, regardless of the time of year, is the birch. In this article, the…

  2. Immersion freezing of birch pollen washing water

    Directory of Open Access Journals (Sweden)

    S. Augustin

    2012-12-01

    Full Text Available In the present study, the immersion freezing behavior of birch pollen, i.e. its ice nucleating active (INA macromolecules, was investigated at the Leipzig Aerosol Cloud Interaction Simulator (LACIS. For that, washing water of two different birch pollen samples with different regional origin (Northern birch and Southern birch were used. The immersion freezing of droplets generated from the pollen washing water was already observed at temperatures higher than −20 °C, for both samples. Main differences between the Northern birch pollen and the Southern birch pollen were obvious in a temperature range, between −18 °C and −24 °C, where the ice fraction increased with decreasing temperature. There, the Northern birch pollen washing water featured two different slopes, with one being steeper and one being similar to the slope of the Southern birch pollen washing water. As we assume single INA macromolecules being the reason for the ice nucleation, we concluded that the Northern birch pollen are able to produce at least two different types of INA macromolecules. We were able to determine the heterogeneous nucleation rates for both INA macromolecule types and so could explain the ice nucleation behavior of both, the Southern and the Northern birch pollen washing water.

  3. Birch's Law for fluid metals

    International Nuclear Information System (INIS)

    By comparing acoustic velocities in fluid metals over a very wide range of densities we have established Birch's Law as an approximate representation over the entire liquid range. For a given liquid metal the acoustic velocity is close to linear in density, with a slope determined by the atomic weight. The measurements include isobaric expansion to less than half normal density, ultrasonics on molten metals at 1 atmosphere, and shock melted metals to greater than twice normal density

  4. Efficacy of recombinant birch pollen vaccine for the treatment of birch-allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Pauli, Gabrielle; Larsen, Tina H; Rak, Sabina;

    2008-01-01

    BACKGROUND: Recombinant DNA technology has the potential to produce allergen-specific immunotherapy vaccines with defined composition. OBJECTIVE: To evaluate the effectiveness of a new recombinant birch pollen allergen vaccine in patients with birch pollen allergy. METHODS: A multicenter......-treated group. CONCLUSION: The rBet v 1-based vaccine was safe and effective in treating birch pollen allergy, and induced a highly specific immune response......., randomized, double-blind, placebo-controlled trial was undertaken to compare the following 3 vaccines in 134 adults with birch pollen allergy: recombinant birch pollen allergen vaccine (rBet v 1a), licensed birch pollen extract, natural purified birch pollen allergen (nBet v 1), and placebo. Patients...

  5. Christian Birch - den korrupte konferensråd

    DEFF Research Database (Denmark)

    Jensen, Mette Frisk

    2005-01-01

      http://www.sidensaxo.dk/fileadmin/saxo-abstract-uploads/christian_birch_den_korrupte_konferensraad_2005_3.pdf......  http://www.sidensaxo.dk/fileadmin/saxo-abstract-uploads/christian_birch_den_korrupte_konferensraad_2005_3.pdf...

  6. VOC emissions from beech, birch, and oak

    Science.gov (United States)

    Wildt, J.; Folkers, A.; Koch, N.; Kleist, E.

    2003-04-01

    VOC emissions from beech (Fagus sylvatica), birch (Betula pendula), and oak (Quercus robur) were studied in continuously stirred tank reactors. Oak emitted nearly exclusively isoprene. The dependence of these isoprene emissions on temperature and photosynthetic radiation (PAR) could quite well be described with existing algorithms and the emission factors were fairly constant. Beech and birch emitted mainly short chained oxygenated VOC and monoterpenes. Temperature and PAR dependence of monoterpene emissions were superimposed by a slow frequency modulation. Hence, descriptions of these emissions with existing algorithms were not successful. Moreover, in some cases the emission pattern switched drastically. For birch it was observed that the plant switched from a sesquiterpene emitter to a monoterpene emitter. emission pattern plants. Emissions of ethanol, acetaldehyde, and methanol were not affected by PAR. Here, the emission factors are determined by other factors not included in existing algorithms.

  7. Birch pollen allergy: molecular characterization and hypoallergenic products

    OpenAIRE

    Schenk, M.F.

    2008-01-01

    Allergic diseases, such as hay fever and food allergy, affect a substantial part of the population in westernized countries. Pollen of the European white birch (Betula pendula) is a considerable cause of hay fever (seasonal allergic rhinitis) in northern and central Europe. The major birch pollen allergen is Bet ν 1, which is the conventional allergen name for the birch pollen proteins of a large group of proteins otherwise known as PR-10 proteins. Individuals that suffer from birch pollen al...

  8. Birch Stands Growth Increase in Western Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Kuzmichev, Valeriy V.; Im, Sergey T.; Ranson, Kenneth J.

    2014-01-01

    Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897-2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40-60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from approx. 63 to approx. 220 cu m/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (r(sub s) = 0.71 to 0.74), atmospheric CO2 concentration (r(sub s) = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, r(sub s) = -0.33 to -0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.

  9. Quantitative DNA Analyses for Airborne Birch Pollen.

    Directory of Open Access Journals (Sweden)

    Isabell Müller-Germann

    Full Text Available Birch trees produce large amounts of highly allergenic pollen grains that are distributed by wind and impact human health by causing seasonal hay fever, pollen-related asthma, and other allergic diseases. Traditionally, pollen forecasts are based on conventional microscopic counting techniques that are labor-intensive and limited in the reliable identification of species. Molecular biological techniques provide an alternative approach that is less labor-intensive and enables identification of any species by its genetic fingerprint. A particularly promising method is quantitative Real-Time polymerase chain reaction (qPCR, which can be used to determine the number of DNA copies and thus pollen grains in air filter samples. During the birch pollination season in 2010 in Mainz, Germany, we collected air filter samples of fine (<3 μm and coarse air particulate matter. These were analyzed by qPCR using two different primer pairs: one for a single-copy gene (BP8 and the other for a multi-copy gene (ITS. The BP8 gene was better suitable for reliable qPCR results, and the qPCR results obtained for coarse particulate matter were well correlated with the birch pollen forecasting results of the regional air quality model COSMO-ART. As expected due to the size of birch pollen grains (~23 μm, the concentration of DNA in fine particulate matter was lower than in the coarse particle fraction. For the ITS region the factor was 64, while for the single-copy gene BP8 only 51. The possible presence of so-called sub-pollen particles in the fine particle fraction is, however, interesting even in low concentrations. These particles are known to be highly allergenic, reach deep into airways and cause often severe health problems. In conclusion, the results of this exploratory study open up the possibility of predicting and quantifying the pollen concentration in the atmosphere more precisely in the future.

  10. Birch pollen allergy: molecular characterization and hypoallergenic products

    NARCIS (Netherlands)

    Schenk, M.F.

    2008-01-01

    Allergic diseases, such as hay fever and food allergy, affect a substantial part of the population in westernized countries. Pollen of the European white birch (Betula pendula) is a considerable cause of hay fever (seasonal allergic rhinitis) in northern and central Europe. The major birch pollen al

  11. BIRCH: A user-oriented, locally-customizable, bioinformatics system

    Directory of Open Access Journals (Sweden)

    Fristensky Brian

    2007-02-01

    Full Text Available Abstract Background Molecular biologists need sophisticated analytical tools which often demand extensive computational resources. While finding, installing, and using these tools can be challenging, pipelining data from one program to the next is particularly awkward, especially when using web-based programs. At the same time, system administrators tasked with maintaining these tools do not always appreciate the needs of research biologists. Results BIRCH (Biological Research Computing Hierarchy is an organizational framework for delivering bioinformatics resources to a user group, scaling from a single lab to a large institution. The BIRCH core distribution includes many popular bioinformatics programs, unified within the GDE (Genetic Data Environment graphic interface. Of equal importance, BIRCH provides the system administrator with tools that simplify the job of managing a multiuser bioinformatics system across different platforms and operating systems. These include tools for integrating locally-installed programs and databases into BIRCH, and for customizing the local BIRCH system to meet the needs of the user base. BIRCH can also act as a front end to provide a unified view of already-existing collections of bioinformatics software. Documentation for the BIRCH and locally-added programs is merged in a hierarchical set of web pages. In addition to manual pages for individual programs, BIRCH tutorials employ step by step examples, with screen shots and sample files, to illustrate both the important theoretical and practical considerations behind complex analytical tasks. Conclusion BIRCH provides a versatile organizational framework for managing software and databases, and making these accessible to a user base. Because of its network-centric design, BIRCH makes it possible for any user to do any task from anywhere.

  12. 75 FR 51987 - Birch Power Company and Sorenson Engineering; Birch Power Company and Sorenson Leasing L.L.C...

    Science.gov (United States)

    2010-08-24

    ... Sorenson Leasing L.L.C.; Notice of Application for Transfer of License, and Soliciting Comments and Motions... (transferors) and Birch Power Company and Sorenson Leasing, L.L.C. (transferees) filed an application for..., Birch Power Company, Sorenson Engineering, and Sorenson Leasing L.L.C., 5203 South 11th East,...

  13. Molecular Ice Nucleation Activity of Birch Pollen

    Science.gov (United States)

    Felgitsch, Laura; Bichler, Magdalena; Häusler, Thomas; Weiss, Victor U.; Marchetti-Deschmann, Martina; Allmaier, Günter; Grothe, Hinrich

    2015-04-01

    Heterogeneous ice nucleation plays a major part in ecosystem and climate. Due to the triggering of ice cloud formation it influences the radiation balance of the earth, but also on the ground it can be found to be important in many processes of nature. So far the process of heterogeneous ice nucleation is not fully understood and many questions remain to be answered. Biological ice nucleation is hereby from great interest, because it shows the highest freezing temperatures. Several bacteria and fungi act as ice nuclei. A famous example is Pseudomonas syringae, a bacterium in commercial use (Snomax®), which increases the freezing from homogeneous freezing temperatures of approx. -40° C (for small volumes as in cloud droplets) to temperatures up to -2° C. In 2001 it was found that birch pollen can trigger ice nucleation (Diehl et al. 2001; Diehl et al. 2002). For a long time it was believed that this is due to macroscopic features of the pollen surface. Recent findings of Bernhard Pummer (2012) show a different picture. The ice nuclei are not attached on the pollen surface directly, but on surface material which can be easily washed off. This shows that not only the surface morphology, but also specific molecules or molecular structures are responsible for the ice nucleation activity of birch pollen. With various analytic methods we work on elucidating the structure of these molecules as well as the mechanism with which they trigger ice nucleation. To solve this we use various instrumental analytic techniques like Nuclear Magnetic Resonance spectroscopy (NMR), Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS), and Gas-phase Electrophoretic Mobility Molecular Analysis (GEMMA). Also standard techniques like various chromatographic separation techniques and solvent extraction are in use. We state here that this feature might be due to the aggregation of small molecules, with agglomerates showing a specific surface structure. Our results

  14. Asymptomatic skin sensitization to birch predicts later development of birch pollen allergy in adults

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Poulsen, Lars K; Malling, Hans-Jørgen

    2003-01-01

    birch skin prick test weal diameter of > or =4 mm, a positive conjunctival provocation test result, and specific IgE of > or =CAP class 2, as well as with the presence of other allergies. Specific IgE of > or =CAP class 2 was 87.5% predictive for allergy development, whereas a negative conjunctival...... risk is any subject with target organ sensitivity, an elevated specific IgE level, and/or a skin prick test weal diameter of >4 mm....

  15. Methods for estimating production and utilization of paper birch saplings

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Development of technique to estimate browse production and utilization. Developed a set of methods for estimating annual production and utilization of paper birch...

  16. Chemical characteristics of surface colour of birch veneer (Betula pendula)

    OpenAIRE

    Yamamoto, Akio

    2015-01-01

    Julkaistu vain painettuna, saatavuus katso Bibid. Published only in printed form, availability see Bibid This thesis investigates the discoloration of veneer produced from silver birch (Betula pendula) logs by means of biochemical and chemical analyses on the veneer and sap obtained from wood which was soaked at varying temperatures (20-70 ˚C). Drastic colour development was confirmed from the sap squeezed from green birch wood. The results from biochemical tests on the sap by sodium dodec...

  17. Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

    Directory of Open Access Journals (Sweden)

    Chiang Vincent L

    2009-09-01

    Full Text Available Abstract Background The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth. would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis. Results Silver birch lines expressing quaking aspen (Populus tremuloides L. caffeate/5-hydroxyferulate O-methyltransferase (PtCOMT under the 35S cauliflower mosaic virus (CaMV promoter showed a reduction in the relative expression of a putative silver birch COMT (BpCOMT gene and, consequently, a decrease in the lignin syringyl/guaiacyl composition ratio. Alterations were also detected in concentrations of certain phenolic compounds. All PtCOMT silver birch lines produced normal ectomycorrhizas with the ectomycorrhizal fungus Paxillus involutus (Batsch: Fr., and the formation of symbiosis enhanced the growth of the transgenic plants. Conclusion The down-regulation of BpCOMT in the 35S-PtCOMT lines caused a reduction in the syringyl/guaiacyl ratio of lignin, but no significant effect was seen in the composition or quantity of phenolic compounds that would have been caused by the expression of PtCOMT under the 35S or UbB1 promoter. Moreover, the detected alterations in the composition of lignin and secondary phenolic compounds had no effect on the interaction between silver birch and P. involutus.

  18. Food allergy to apple and specific immunotherapy with birch pollen

    DEFF Research Database (Denmark)

    Hansen, Kirsten Skamstrup; Khinchi, Marianne Søndergaard; Skov, Per Stahl;

    2004-01-01

    Conflicting results concerning the effect of specific pollen immunotherapy (SIT) on allergy to plant foods have been reported. The aim of this study was to investigate the effect of SIT using a birch pollen extract on food allergy with focus on allergy to apple. Seventy-four birch pollen-allergic......Conflicting results concerning the effect of specific pollen immunotherapy (SIT) on allergy to plant foods have been reported. The aim of this study was to investigate the effect of SIT using a birch pollen extract on food allergy with focus on allergy to apple. Seventy-four birch pollen......-allergic patients were included in a double-blind, double-dummy, and placebo-controlled comparison of sublingual-swallow (SLIT) and subcutaneous (SCIT) administration of a birch pollen extract. Sixty-nine percent of these patients reported allergy to apple. The clinical reactivity to apple was evaluated by open...... oral challenges with fresh apple and a questionnaire. The immunoglobulin E (IgE)-reactivity was assessed by skin prick test (SPT), specific IgE, and leukocyte histamine release (HR). Forty patients were included in the final evaluation of the effect of SIT. The challenges were positive in 9 (SCIT), 6...

  19. The growth process of natural poplar-birch forests

    Institute of Scientific and Technical Information of China (English)

    LAN Shibo; LUO Xu; LUO Yuliang

    2006-01-01

    With a combination of permanent and temporary sample plots,we investigated the growth conditions of natural poplar-birch forests.The forests were divided into four site classes,using statistical and analytical techniques in a quantitative model,in descending order where site class I was the best.On this basis,the growth of natural poplar-birch forests in the different site classes was studied.The growth processes of height and diameter at breast height were divided into three stages:a fast growing period,a stable growing period and a slow growing period.Results of this study provide a theoretical basis for the directive cultivation of natural poplar-birch forests.

  20. White Birch Trees as Resource Species of Russia : Their Distribution, Ecophysiological Features, Multiple Utilizations

    OpenAIRE

    Zyryanova, Olga A.; TERAZAWA, Minoru; KOIKE, TAKAYOSHI; Zyryanov, Vyacheslav I.

    2010-01-01

    Four birch tree species (Betula costata, B. pendula, B. platyphylla, B. pubescens) are traditionally important resource species in Russia. In the article, we discuss their spatial and ecophysiological features, biochemical constituents of the living tissues of the birches such as the wood, outer and inner bark, twigs, leaves, buds, roots. The exudation, tapping periods and sap productivity, exudated birch sap and derived birch tar are also reviewed. We show numerous useful wooden, medicinal, ...

  1. [Soil nutrient status of pure birch and larch plantations based on their seedlings bioassay].

    Science.gov (United States)

    Liu, Zhong-ling; Wang, Qing-cheng; Sun, Xin-xin

    2011-08-01

    One-year-old birch (Betula platyphylla) and larch (Larix olgensis) seedlings were respectively planted in pots with the soils taken from 35-year-old pure birch and larch plantations, and the seedlings growth, biomass increment, foliar nutrient content, and soil nutrient status were monitored, aimed to evaluate the fertility levels of the two soils and the possible interspecific interaction in mixed larch-birch forest. Birch soil had significantly higher contents of total N and available N than larch soil, while larch soil had significantly higher contents of total P, available P, and total K than birch soil (P birch seedlings growing on birch soil were 69%, 52%, and 65% (P birch seedlings growing on birch soil was higher than that on larch soil, while the foliar P concentration was higher when the seedlings were growing on larch soil than on birch soil. The birch soil had higher content of available N because of the higher litterfall, while the larch soil had greater available P because of the higher P mobilizing effect. It was predicted that in mixed birch-larch forest, the complementary interaction of soil N and P could benefit the growth of the two tree species.

  2. Mycobionta of birch and birch stump roots and its possible effect on the infection by Armillaria spp. I.

    Directory of Open Access Journals (Sweden)

    Hanna Kwaśna

    2014-08-01

    Full Text Available Zygorhynchus moelleri was the dominating species on/in roots of 2 year-old stumps of the 49 year-old birches. Trichoderma viride was more frequently found in the fine roots of living birches than in the fine roots of stumps though its population increased in thick roots of stumps. Occasionally the fungus also occurred on the surface of fine roots of stumps. Z. moelleri is known to produce indole 3-ethanol and indole-3 acetic acid which stimulate the growth of A. ostoyae rhizomorphs and phenoloxidizing enzymes which play an important role in the degradation of the wood. It seems that the accumulation of Z. moelleri and absence of bigger populations of T. viride on/in roots of 2-year-old stumps of the 49 year-old birches may result in an increase of their susceptibility to Armillaria infection.

  3. Fluctuation of birch (Betula L. pollen seasons in Poland

    Directory of Open Access Journals (Sweden)

    Małgorzata Puc

    2015-12-01

    Full Text Available Birch pollen grains are one of the most important groups of atmospheric biological particles that induce allergic processes. The fluctuation pattern of birch pollen seasons in selected cities of Poland is presented. Measurements were performed by the volumetric method (Burkard and Lanzoni 2000 pollen samplers. The distributions of the data were not normal (Shapiro–Wilk test and statistical error risk was estimated at a significance level of α = 0.05. Pollen season was defined as the period in which 95% of the annual total catch occurred. The linear trend for the selected features of the pollen season, skewness, kurtosis and coefficient of variation (V% were also analyzed. During the 12–14 years of study, the beginnings of birch pollen seasons were observed 7–14 days earlier, the ends were noted 5–10 days earlier, and the days with maximum values occurred 7–14 days earlier compared to the long-term data. The left-skewed distribution of the pollen season starts in most sampling sites confirms the short-lasting occurrence of pollen in the air. The threat of birch pollen allergens was high during the pollen seasons. If vegetation is highly diverse, flowering and pollen release are extended in time, spread over different weeks and occur at different times of the day. Flowering time and pollen release are affected by insolation, convection currents, wind, and turbulence. Therefore, pollen seasons are characterized by great inter-annual variability.

  4. Conspiracy Drama and the John Birch Society: A Movement Reconsidered.

    Science.gov (United States)

    Hollihan, Thomas A.

    This paper examines the conspiracy drama which characterizes the rhetoric generated by the John Birch Society. According to the Society, "innocent" America is under direct threat from some organized external and internal force that is seeking its destruction. Members are called to react in a carefully outlined manner: (1) piece together the…

  5. BIRCH XYLAN GRAFTED WITH PLA BRANCHES OF PREDICTABLE LENGTH

    OpenAIRE

    Johanna Persson,; Olof Dahlman,; Ann-Christine Albertsson

    2012-01-01

    Birch xylan (4-O-methylglucuronoxylan) isolated from a kraft cooking liquor was delignified and grafted with polylactide of predictable branch length. This graft copolymerization resulted in very high total yields, greater than 90%, and with less than 10% polylactide homopolymer byproducts. Mild reaction conditions (40°C, 5 to 120 minutes) were used, which was believed to limit transesterification reactions and thus make it possible to reach good predictability of the polylactide branch lengt...

  6. Paper birch: Sentinels of climate change in the Niobrara River Valley, Nebraska

    Science.gov (United States)

    Stroh, Esther D.

    2011-01-01

    The Niobrara River Valley in the northern Great Plains supports scattered stands of paper birch (Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation. Localized summer microclimates have likely facilitated the persistence of birch populations in a region otherwise unsuitable for the species. Dieback of canopy-sized birch has been observed throughout the valley in recent years, although no onset dates are documented. Changes in spring weather patterns may be causing rootlet injury so that trees die in spite of the still-cool summer microclimates. Current weather patterns, combined with little evidence of recruitment of young birch and great geographic distances from potential immigrant sources, make the future persistence of birch in the Niobrara River Valley stands uncertain.

  7. Attempts at active protection of Inonotus obliquus by inoculating birches with its mycelium

    OpenAIRE

    Jacek Piętka; Andrzej Grzywacz

    2013-01-01

    Practical application of active protection methods of Inonotus obliquus (Fr.) Pilát. was examined. Thirty live birches and 15 birch stem sections were artificially inoculated with the fungal mycelium in the Mińsk Forest District (E Poland). The mycelium of I. obliquus was not recorded in the felled test trees and birch stem sections upon the completion of the experiment. Artificial introduction of I. obliquus in the natural environment faces significant problems caused by strong competition f...

  8. Mycobionta of birch and birch stump roots and its possible effect on the infection by Armillaria spp. II.

    Directory of Open Access Journals (Sweden)

    Hanna Kwaśna

    2014-08-01

    Full Text Available This paper presents the differences in size and structure of mycobionta communities occurring in soil and on/i n roots of a 30 year-old birch and its stumps 2 years after cutting of the trees. Special attention was paid to the occurrence of Zygorhynchus moelleri and Trichoderma viride. The first species due to the metabolites produced may presumably stimulate the infection by Armlllaria. The second species is a well-known antagonist of Armillaria, Z. moelleri accounted only for 2.6, l.3 and 9.l % of the total number of isolates in rhizoplane as well as in the fine and thick roots of stumps, respectively. Trlchodcrma viride and T. virens were present in roots of Hve birch and its stumps only occasionally. The relatively big population of Mycelium radicis atrovirens- particularly in the fine roots of stumps is attributed to their high vitality and relatively lower level of root decomposition. It seems that the rate of stump root decomposilion does not favour their colonization by Z. moelleri and its supposed contribution in enhancing the infection by Armillaria might not be so distinct as on stumps of 49-year-old birches.

  9. Survival and growth for pubescent birch, pendula birch and common alder growing on farmland areas; Oeverlevnad och tillvaext hos glasbjoerk, vaartbjoerk och klibbal planterade paa aakermark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Tord

    2000-07-01

    Pendula birches (Betula pendula Roth) and pubescent birches (Betula pubescens Ehrh.) were planted on former farmland. Before planting, the ground was harrowed or the ground was sprayed with terbuthylazine. Tree shelters were used as protection against weeds, voles and wild habitat. Birches treated with terbuthylazine showed the lowest survival. Birches growing in tree shelters were tallest and those growing on spots treated with terbuthylazine were smallest. The diameter at 0.1 m did not differ in a statistically significant way between the treatments. In another experiment with different herbicides, common alder (Alnus glutinosa (L.) Gaertn.) and pendula birch (Betula pendula Roth) were planted on former farmland that had been treated with glyphosate, terbuthylazine and propyzamide or after ground had been harrowed or not treated. In the study on herbicide-treated plants, birch had the highest plant survival. Mostly, species treated with glyphosate were thicker than species treated in other ways. Both species appeared sensitive to terbuthylazine, but not to glyphosate. Birch was not sensitive for propyzamide in opposite to alder. Some practical recommendations concerning afforestation of former farmland, especially weeding, are given.

  10. Boron nutrition affects the carbon metabolism of silver birch seedlings.

    Science.gov (United States)

    Ruuhola, Teija; Keinänen, Markku; Keski-Saari, Sarita; Lehto, Tarja

    2011-11-01

    Boron (B) is an essential micronutrient whose deficiency is common both in agriculture and in silviculture. Boron deficiency impairs the growth of plants and affects many metabolic processes like carbohydrate metabolism. Boron deficiency and also excess B may decrease the sink demand by decreasing the growth and sugar transport which may lead to the accumulation of carbohydrates and down-regulation of photosynthesis. In this study, we investigated the effects of B nutrition on the soluble and storage carbohydrate concentrations of summer leaves and autumn buds in a deciduous tree species, Betula pendula Roth. In addition, we investigated the changes in the pools of condensed tannins between summer and autumn harvests. One-year-old birch seedlings were fertilized with a complete nutrient solution containing three different levels of B: 0, 30 and 100% of the standard level for complete nutrient solution. Half of the seedlings were harvested after summer period and another half when leaves abscised. The highest B fertilization level (B100) caused an accumulation of starch and a decrease in the concentrations of hexoses (glucose and fructose) in summer leaves, whereas in the B0 seedlings, hexoses (mainly glucose) accumulated and starch decreased. These changes in carbohydrate concentrations might be related to the changes in the sink demand since the autumn growth was the smallest for the B100 seedlings and largest for the B30 seedlings that did not accumulate carbohydrates. The autumn buds of B30 seedlings contained the lowest levels of glucose, glycerol, raffinose and total polyols, which was probably due to the dilution effect of the deposition of other substances like phenols. Condensed tannins accumulated in high amounts in the birch stems during the hardening of seedlings and the largest accumulation was detected in the B30 treatment. Our results suggest that B nutrition of birch seedlings affects the carbohydrate and phenol metabolism and may play an important

  11. Specific probiotics alleviate allergic rhinitis during the birch pollen season

    Institute of Scientific and Technical Information of China (English)

    Arthur C Ouwehand; Merja Nermes; Maria Carmen Collado; Nina Rautonen; Seppo Salminen; Erika Isolauri

    2009-01-01

    AIM: To investigate whether birch pollen allergy symptoms are linked with gut microbiota changes and whether probiotics have an effect on these. METHODS: Forty seven children with confirmed birch pollen allergy were randomized to receive either a probiotic combination of Lactobacillus acidophilus ( L. acidophi lus) NCFMTM (ATCC 700396) and Bifidobacterium lactis ( B. lactis) Bl-04 (ATCC SD5219) or placebo in a double-blind manner for 4 mo, starting prior to onset of the birch pollen season. Symptoms were recorded in a diary. Blood samples were taken for analysis of cytokines and eosinophils. Fecal samples were analysed for microbiota components, calprotectin and IgA. Nasal swabs were taken for analysis of eosinophils.RESULTS: The pollen season induced a reduction in Bifidobacterium, Clostridium and Bacteroides which could not be prevented by the probiotic intervention. During the intervention, significantly higher numbers 106 bacteria/g feces ( P < 0.0001) were observed in the probiotic group compared to the placebo group. During May, there was a tendency for fewer subjects,(76.2% vs 95.2%, P = 0.078) to report runny nose,while during June, fewer subjects, 11.1% vs 33.3%,reported nasal blocking in the probiotics group ( P = 0.101). Concomitantly, fewer subjects in the probiotic group had infiltration of eosinophils in the nasal mucosa compared to the placebo group, 57.1%vs 95% ( P = 0.013). Eye symptoms tended to be slightly more frequent in the probiotic group, 12.5 d [interquartile range (IQR) 6-18] vs 7.5 d (IQR 0-11.5)( P = 0.066) during May. Fecal IgA was increased in the placebo group during the pollen season; this increase was prevented by the probiotics ( P = 0.028).CONCLUSION: Birch pollen allergy was shown to be associated with changes in fecal microbiota composition. The specific combination of probiotics used was shown to prevent the pollen-induced infiltration of eosinophils into the nasal mucosa, and indicated a trend for reduced nasal symptoms.

  12. Effect of birch (Betula spp.) and associated rhizoidal bacteria on the degradation of soil polyaromatic hydrocarbons, PAH-induced changes in birch proteome and bacterial community.

    Science.gov (United States)

    Tervahauta, Arja I; Fortelius, Carola; Tuomainen, Marjo; Akerman, Marja-Leena; Rantalainen, Kimmo; Sipilä, Timo; Lehesranta, Satu J; Koistinen, Kaisa M; Kärenlampi, Sirpa; Yrjälä, Kim

    2009-01-01

    Two birch clones originating from metal-contaminated sites were exposed for 3 months to soils (sand-peat ratio 1:1 or 4:1) spiked with a mixture of polyaromatic hydrocarbons (PAHs; anthracene, fluoranthene, phenanthrene, pyrene). PAH degradation differed between the two birch clones and also by the soil type. The statistically most significant elimination (p birch, the clearest positive effect being found with Betula pubescens clone on phenanthrene. PAHs and soil composition had rather small effects on birch protein complement. Three proteins with clonal differences were identified: ferritin-like protein, auxin-induced protein and peroxidase. Differences in planted and non-planted soils were detected in bacterial communities by 16S rRNA T-RFLP, and the overall bacterial community structures were diverse. Even though both represent complex systems, trees and rhizoidal microbes in combination can provide interesting possibilities for bioremediation of PAH-polluted soils.

  13. Genetic and environmental factors behind foliar chemistry of the mature mountain birch.

    Science.gov (United States)

    Haviola, Sanna; Neuvonen, Seppo; Rantala, Markus J; Saikkonen, Kari; Salminen, Juha-Pekka; Saloniemi, Irma; Yang, Shiyong; Ruuhola, Teija

    2012-07-01

    Previous studies of mountain birch (Betula pubescens spp. czerepanovii) repeatedly have found differences between individual trees in herbivory-related traits, but rarely have yielded estimates of the additive genetic variation of these traits or of their relationship to habitat. We used thirty-year-old birch half-sibs in a northern common garden to estimate the effect of genetics and local microhabitat on resistance-related traits. Genetic estimates of foliar chemistry have been studied only rarely with trees as old as these. Moth performance (Epirrita autumnata), rust (Melampsoridium betulinum) incidence levels, and the general level of natural herbivory damage to individual trees were used as direct measures of birch resistance. Chemical resistance-related traits in plant chemistry included 15 individual phenolics, 16 amino acids, and phenoloxidase activities in the foliage. We also followed birch phenology and growth. Our results show that the genotype of the birch was the most important determinant of phenolic composition and phenoloxidase activity, but that amino acid levels were best explained by the microhabitat of the birch. We also found that the phenology of the birch had a high heritability, although its variation was low. Our results reveal rich genetic variation in birch chemistry.

  14. Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily

    Directory of Open Access Journals (Sweden)

    Bagnato S

    2014-04-01

    Full Text Available Evolutionary dynamics of birch (Betula aetnensis Rafin coppices on the Mount Etna (Sicily. The aim of this paper is to evaluate the dynamics of Etna birch stands (Betula aetnensis Rafin following the cessation of silvicultural activities in the Etna Regional Park (Sicily. We investigated forest structure, natural regeneration, vegetation and deadwood in different forest types. Our findings highlighted three different dynamics for birch populations: stable birch stands in the high mountain area which might represent an edapho-climax forest; progressive dynamic birch stands in the intermediate mountain area, showing a gradual depletion of birch and a concomitant replacement with monospecific stands (calabrian pine, beech, oaks or mixed ones (with birch; pure birch stands (typical that tend to be regressive - especially under stressful conditions - and to be replaced by xerophilous grasslands. Following the cessation of coppicing and with stand ageing, the stumps transformation into more homogeneous stand structures have been increasing. Within the context of protected areas the restoration of coppice selection system (with appropriate adaptations could help to maintain the traditional forest landscape, acting as a silvicultural technique with low environmental and landscape impact.

  15. Attempts at active protection of Inonotus obliquus by inoculating birches with its mycelium

    Directory of Open Access Journals (Sweden)

    Jacek Piętka

    2013-12-01

    Full Text Available Practical application of active protection methods of Inonotus obliquus (Fr. Pilát. was examined. Thirty live birches and 15 birch stem sections were artificially inoculated with the fungal mycelium in the Mińsk Forest District (E Poland. The mycelium of I. obliquus was not recorded in the felled test trees and birch stem sections upon the completion of the experiment. Artificial introduction of I. obliquus in the natural environment faces significant problems caused by strong competition from other birch wood-decay fungi. As in vitro studies show (individual biotic effect determination, the fungi examined, occurring on birch trees in nature, are dominant species in relation to I. obliquus.

  16. Stimulated production of steroids in Inonotus obliquus by host factors from birch.

    Science.gov (United States)

    Wang, Lian-Xia; Lu, Zhen-Ming; Geng, Yan; Zhang, Xiao-Mei; Xu, Guo-Hua; Shi, Jin-Song; Xu, Zheng-Hong

    2014-12-01

    Steroids was considered as one of the bioactive components in Inonotus obliquus, while this kind of secondary metabolites are less accumulated in cultured mycelia. In this study, effect of extracts from bark and core of host-related species, birch (Betula platyphylla Suk.), on steroid production of I. obliquus in submerged culture were evaluated. The results showed that all dosages (0.01 and 0.1 g/L) of aqueous extracts and methanol extracts from birch bark and birch core possessed significantly stimulatory effect on steroid production of I. obliquus (P obliquus simultaneously increased in the presence of aqueous extract and methanol extract from birch bark. The results presented herein indicate that extracts from birch bark could act as an inducer for steroid biosynthesis of I. obliquus. PMID:25027706

  17. Bioconversion of Birch Wood Hemicellulose Hydrolyzate to Xylitol.

    Science.gov (United States)

    Miura, Masahiro; Shimotori, Yasutaka; Nakatani, Hisayuki; Harada, Akira; Aoyama, Masakazu

    2015-06-01

    A sugar solution containing 42.9 g l(-1) of xylose was prepared from the wood of Japanese white birch (Betula platyphylla var. japonica) by hydrolysis with 3 % sulfuric acid with a liquor-to-solid ratio of 4 (g g(-1)) at 120 °C for 1 h. During the acid hydrolysis, undesirable by-products were generated, such as acetic acid, furfural, and low-molecular-weight phenols, which inhibit bioconversion of xylose to xylitol. These inhibitors were successfully removed from the hydrolyzate by sorption onto a steam-activated charcoal followed by treatment with an anion exchange resin. Bioconversion of the detoxified hydrolyzate to xylitol by the yeast Candida magnoliae was investigated under the microaerobic conditions. The oxygen transfer rate (OTR) varied from 9.6 to 22.3 mmol O2 l(-1) h(-1). The best fermentative performance of C. magnoliae in the birch wood hydrolyzate (xylitol yield 0.74 g xylitol g xylose(-1); volumetric productivity 1.0 g l(-1) h(-1)) was obtained at the OTR of 12.6 mmol O2 l(-1) h(-1). PMID:25894947

  18. Growth and Leaf Gas Exchange in Three Birch Species Exposed to Elevated Ozone and CO2 in Summer

    OpenAIRE

    HOSHIKA, Yasutomo; Watanabe, Makoto; Inada, Naoki; Koike, Takayoshi

    2012-01-01

    We examined the effects of ozone and elevated CO2 concentration in summer on the growth and photosynthetic traits of three representative birch species in Japan (mountain birch, Monarch birch, and white birch). Seedlings of the three birch species were grown in 16 open-top chambers and were exposed to two levels of ozone (6 nmol mol^[-1] and 60 nmol mol^[-1] for 7 h per day) in combination with two levels of CO2 (370-380μmol mol^[-1] and 600 μmol mol^[-1] for daytime) from July to October. No...

  19. ALKALINE PRETREATMENT OF SPRUCE AND BIRCH TO IMPROVE BIOETHANOL AND BIOGAS PRODUCTION

    Directory of Open Access Journals (Sweden)

    Azam Jeihanipour

    2010-05-01

    Full Text Available Alkaline pretreatment with NaOH under mild operating conditions was used to improve ethanol and biogas production from softwood spruce and hardwood birch. The pretreatments were carried out at different temperatures between minus 15 and 100ºC with 7.0% w/w NaOH solution for 2 h. The pretreated materials were then enzymatically hydrolyzed and subsequently fermented to ethanol or anaerobically digested to biogas. In general, the pretreatment was more successful for both ethanol and biogas production from the hardwood birch than the softwood spruce. The pretreatment resulted in significant reduction of hemicellulose and the crystallinity of cellulose, which might be responsible for improved enzymatic hydrolyses of birch from 6.9% to 82.3% and spruce from 14.1% to 35.7%. These results were obtained with pretreatment at 100°C for birch and 5°C for spruce. Subsequently, the best ethanol yield obtained was 0.08 g/g of the spruce while pretreated at 100°C, and 0.17 g/g of the birch treated at 100°C. On the other hand, digestion of untreated birch and spruce resulted in methane yields of 250 and 30 l/kg VS of the wood species, respectively. The pretreatment of the wood species at the best conditions for enzymatic hydrolysis resulted in 83% and 74% improvement in methane production from birch and spruce.

  20. Sound velocities of hot dense iron: Birch's law revisited.

    Science.gov (United States)

    Lin, Jung-Fu; Sturhahn, Wolfgang; Zhao, Jiyong; Shen, Guoyin; Mao, Ho-Kwang; Hemley, Russell J

    2005-06-24

    Sound velocities of hexagonal close-packed iron (hcp-Fe) were measured at pressures up to 73 gigapascals and at temperatures up to 1700 kelvin with nuclear inelastic x-ray scattering in a laser-heated diamond anvil cell. The compressional-wave velocities (VP) and shear-wave velocities (VS) of hcp-Fe decreased significantly with increasing temperature under moderately high pressures. VP and VS under high pressures and temperatures thus cannot be fitted to a linear relation, Birch's law, which has been used to extrapolate measured sound velocities to densities of iron in Earth's interior. This result means that there are more light elements in Earth's core than have been inferred from linear extrapolation at room temperature. PMID:15976298

  1. Stature of Sub-arctic Birch in Relation to Growth Rate, Lifespan and Tree Form

    OpenAIRE

    JÓNSSON, THORBERGUR HJALTI

    2004-01-01

    • Background and Aims Sub-arctic mountain birch Betula pubescens var. pumila communities in the North Atlantic region are of variable stature, ranging from prostrate scrubs to forests with trees up to 12 m high. Four hypotheses were tested, relating growth and population characteristics of sub-arctic birch woodland and scrub to tree stature; i.e. the variable stature of birch woods is due to differences in (1) the mean growth rate; (2) the age-related patterns of growth rate; (3) the life exp...

  2. Effect of birch (Betula spp.) and associated rhizoidal bacteria on the degradation of soil polyaromatic hydrocarbons, PAH-induced changes in birch proteome and bacterial community

    Energy Technology Data Exchange (ETDEWEB)

    Tervahauta, Arja I. [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland)], E-mail: arja.tervahauta@uku.fi; Fortelius, Carola [EVTEK University of Applied Sciences, Vantaa (Finland); Tuomainen, Marjo [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Akerman, Marja-Leena [EVTEK University of Applied Sciences, Vantaa (Finland); Rantalainen, Kimmo [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Sipilae, Timo [Department of Biological and Environmental Sciences, University of Helsinki (Finland); Lehesranta, Satu J.; Koistinen, Kaisa M.; Kaerenlampi, Sirpa [Department of Biosciences, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Yrjaelae, Kim [Department of Biological and Environmental Sciences, University of Helsinki (Finland)

    2009-01-15

    Two birch clones originating from metal-contaminated sites were exposed for 3 months to soils (sand-peat ratio 1:1 or 4:1) spiked with a mixture of polyaromatic hydrocarbons (PAHs; anthracene, fluoranthene, phenanthrene, pyrene). PAH degradation differed between the two birch clones and also by the soil type. The statistically most significant elimination (p {<=} 0.01), i.e. 88% of total PAHs, was observed in the more sandy soil planted with birch, the clearest positive effect being found with Betula pubescens clone on phenanthrene. PAHs and soil composition had rather small effects on birch protein complement. Three proteins with clonal differences were identified: ferritin-like protein, auxin-induced protein and peroxidase. Differences in planted and non-planted soils were detected in bacterial communities by 16S rRNA T-RFLP, and the overall bacterial community structures were diverse. Even though both represent complex systems, trees and rhizoidal microbes in combination can provide interesting possibilities for bioremediation of PAH-polluted soils. - Birch can enhance degradation of PAH compounds in the rhizosphere.

  3. Daily home measurements of exhaled nitric oxide in asthmatic children during natural birch pollen exposure

    DEFF Research Database (Denmark)

    Vahlkvist, Signe; Sinding, Marianne; Skamstrup, Kirsten;

    2006-01-01

    the feasibility, repeatability, accuracy, sensitivity, and biologic plausibility of new handheld equipment for FENO measurements. We studied day-to-day home measurements of FENO during the birch pollen season in children with allergy to birch pollen and a history of mild asthma and rhinoconjunctivitis during......BACKGROUND: Fractional exhaled nitric oxide (FENO) is a sensitive marker of eosinophilic airway inflammation in asthma. Available methods have restricted measurements to the clinic, giving only a snapshot of the disease, which by nature is highly variable. OBJECTIVES: We sought to investigate...... this season, as well as in nonatopic children. METHODS: Eleven children with mild asthma and allergy to birch pollen, performed daily home measurements of FENO for 6 weeks before and during the birch pollen season by using a handheld FENO monitor (NIOX MINO). Additionally, FENO (chemiluminescence equipment...

  4. Inhibition of corneal inflammation following keratoplasty by birch leaf extract.

    Science.gov (United States)

    Wacker, Katrin; Gründemann, Carsten; Kern, Yvonne; Bredow, Laura; Huber, Roman; Reinhard, Thomas; Schwartzkopff, Johannes

    2012-04-01

    The objective of this study was to determine the effect of birch leaf (Betula pendula) extract (BPE) on corneal inflammation following keratoplasty in the rat model. T cells were stimulated in vitro in the presence of BPE. Proliferation, activation phenotype and the number of apoptotic/necrotic cells in cell culture were analyzed by flow cytometry. Corneal transplantation was performed between Fisher and Lewis rats. Recipient rats were either treated with cyclosporine A at a low dosage (Low-dose CsA=LDCsA) or received LDCsA in combination with BPE (2×1ml/day). Clinical signs for corneal inflammation and rejection time points were determined. Infiltrating leukocytes were analyzed histologically. BPE specifically inhibited T cell proliferation in vitro by inducing apoptosis. The phenotype was not affected. In vivo, BPE significantly delayed the onset of corneal opacification (p<0.05). The amount of infiltrating CD45(+) leukocytes and CD4(+) T cells (p<0.001) was significantly reduced by BPE, whereas infiltration of CD163(+) macrophages was not significantly different between the two groups. BPE selectively induces apoptosis of activated T cells. Accordingly, BPE treatment significantly reduces infiltrating T cells and subsequent corneal opacification following keratoplasty. Our findings suggest BPE as a promising anti-inflammatory drug to treat corneal inflammation.

  5. BIRCH XYLAN GRAFTED WITH PLA BRANCHES OF PREDICTABLE LENGTH

    Directory of Open Access Journals (Sweden)

    Johanna Persson,

    2012-06-01

    Full Text Available Birch xylan (4-O-methylglucuronoxylan isolated from a kraft cooking liquor was delignified and grafted with polylactide of predictable branch length. This graft copolymerization resulted in very high total yields, greater than 90%, and with less than 10% polylactide homopolymer byproducts. Mild reaction conditions (40°C, 5 to 120 minutes were used, which was believed to limit transesterification reactions and thus make it possible to reach good predictability of the polylactide branch length. The thermal properties of the polylactide-grafted xylan depended on the branch length. Short branches resulted in fully amorphous materials with a glass transition temperature of about 48 to 55°C, whereas long polylactide branches resulted in semi-crystalline materials with melting points of about 130°C. Using mixtures of L-lactide and D/L-lactide in the monomer feed further altered the thermal properties. The degradation temperatures of the polylactide-grafted xylans were higher than that of the unmodified xylan, with degradation temperatures of about 300°C and 250°C, respectively. Tensile testing showed increased elongation at break with increasing branch length. The proposed method thus enables tailor-making of copolymers with specific thermal and mechanical properties.

  6. Damping properties of sequoia and birch under shock loading

    International Nuclear Information System (INIS)

    The decrease mechanic effect on loads being transported, shock load limiters (dampers) are being widely used today. Usually, the materials having 'stress-strain' diagrams (σ-ε) of compression with a substantial portion, where σ = const., are used as dampers. Most widely used are dampers made of foam polystyrene having just the same compression diagram. Similar strain diagrams can be enlisted for some porous materials, timber under cross compression, perforated metallic crushers and some others. By selecting damper material, the level of transmitted to the protected object pressures can be varied from several to hundreds MPa. Timber, as being widely used and featuring good technologic properties together with low cost, becomes an attractive material to be used as the limiter of shock loads. This paper presents the results of stress-strain sequoia properties (USA deliverable) and birch properties (Volgo-Vyatski region) at dynamic (v = 10 m/s) and quasistatic (v ≅ 10-4 m/s) loading rates. The samples (diameter 25 x 25 mm) cut at 0, 5, 10, 15, 30, 45 and 90 deg. angle relative to their fibre were tested on one-axis compression at -30, +20 and +65 deg. C and fixed humidity (ω = 6-7%). Dynamic tests employed Kolsky method performed at the facility including Hopkinson's compound rod (Zukas et al.,1985). Sample loading was executed by trapezoidal pulsed pressure created by the explosive device. Samples were heated and cooled by special thermostats. (authors)

  7. Ecological and phytopathological status of birch stands on the territory of Krasnoyarsk group of districts

    Directory of Open Access Journals (Sweden)

    A. I. Tatarintsev

    2015-04-01

    Full Text Available According to inspection data, the health and vital status of birch (Betula pendula Roth. stands in Krasnoyarsk group of lands (southern part of Central Siberia were estimated (established as satisfactory in general; about half of birch stands near urbanized areas were weakened. The condition of stands decreased significantly with increased recreation use, the effect of technogenic pollution was negligible. The most valuable (important representatives of pathogenic biota identified on birch trees were infestations of necrotic cancer and rot diseases. In birch stands the bacterial dropsy was found to be widespread (agent of infection – Erwinia multivora Scz.-Parf, occurrence of the disease ranged from a single ill tree up to 10–38 % of the stands. The birch stands in taiga areas were affected to a greater extent than in forest-steppe; there were high yield class stands on moist soils. Prevalence of bacteriosis rose with increasing stand age and density and not dependent on recreation use level. Trees with dropsy are dead in fact or potentially. In taiga birch forests the infection and rot of roots was caused by honey agaric (Armillaria mellea sensu lato, that lead to single or, rarely, group tree drying and the fungus usually eliminated already weakened trees. Wood biomass was destroyed by complex of aphyllophorous Hymenomycetes, their hemiparasitic species caused stem rots that decreased stand marketability and also resulted in rot-realated wind-break accumulation. Occurrence of rot was significantly higher in second growth birch stands, possibly above 20 %; the relationship between rot prevalence and forest assessment was not revealed.

  8. Spatial heterogeneity in the timing of birch budburst in response to future climate warming in Ireland

    Science.gov (United States)

    Caffarra, Amelia; Zottele, Fabio; Gleeson, Emily; Donnelly, Alison

    2014-05-01

    In order to predict the impact of future climate warming on trees it is important to quantify the effect climate has on their development. Our understanding of the phenological response to environmental drivers has given rise to various mathematical models of the annual growth cycle of plants. These models simulate the timing of phenophases by quantifying the relationship between development and its triggers, typically temperature. In addition, other environmental variables have an important role in determining the timing of budburst. For example, photoperiod has been shown to have a strong influence on phenological events of a number of tree species, including Betula pubescens (birch). A recently developed model for birch (DORMPHOT), which integrates the effects of temperature and photoperiod on budburst, was applied to future temperature projections from a 19-member ensemble of regional climate simulations (on a 25 km grid) generated as part of the ENSEMBLES project, to simulate the timing of birch budburst in Ireland each year up to the end of the present century. Gridded temperature time series data from the climate simulations were used as input to the DORMPHOT model to simulate future budburst timing. The results showed an advancing trend in the timing of birch budburst over most regions in Ireland up to 2100. Interestingly, this trend appeared greater in the northeast of the country than in the southwest, where budburst is currently relatively early. These results could have implications for future forest planning, species distribution modeling, and the birch allergy season.

  9. Structural analysis of heat-treated birch (Betule papyrifera) surface during artificial weathering

    Energy Technology Data Exchange (ETDEWEB)

    Huang Xianai [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Kocaefe, Duygu, E-mail: dkocaefe@uqac.ca [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Kocaefe, Yasar [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada); Boluk, Yaman [University of Alberta, 3-142 Markin/CNRL Natural Resources Engineering Facility, Edmonton, Alberta, T6G 2W2 (Canada); Krause, Cornelia [Universite du Quebec a Chicoutimi, 555, boul. de l' Universite, Chicoutimi, Quebec, G7H 2B1 (Canada)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Investigate detailed structural changes of heat-treated wood due to weathering. Black-Right-Pointing-Pointer Identify connection between physical structural changes and chemical degradation. Black-Right-Pointing-Pointer Study effect of heat treatment conditions on weathering degradation process. - Abstract: Effect of artificial weathering on the surface structural changes of birch (Betule papyrifera) wood, heat-treated to different temperatures, was studied using the fluorescence microscopy and the scanning electron microscopy (SEM). Changes in the chemical structure of wood components were analyzed by FTIR in order to understand the mechanism of degradation taking place due to heat treatment and artificial weathering. The results are compared with those of the untreated (kiln-dried) birch. The SEM analysis results show that the effect of weathering on the cell wall of the untreated birch surface is more than that of heat-treated samples. The FTIR spectroscopy results indicate that lignin is the most sensitive component of heat-treated birch to the weathering degradation process. Elimination of the amorphous and highly crystallised cellulose is observed for both heat-treated and untreated wood during weathering. It is also observed that heat treatment increases the lignin and crystallised cellulose contents, which to some extent protects heat-treated birch against degradation due to weathering.

  10. The Puzzling Origin of the Acquaintance between Charlotte Lennox and Thomas Birch

    Directory of Open Access Journals (Sweden)

    Patricia L. Hamilton

    2015-03-01

    Full Text Available Scholars have puzzled over the origin of the relationship between Charlotte Lennox and Thomas Birch. That the two shared a cordial professional relationship in 1759 is not surprising, but it is unclear how and when Birch obtained the poem "The Dream, an ode by Miss Ramsey of 15" (ca. 1744-45 for his manuscript collection. Possibly Edward Cave, publisher of The Gentleman’s Magazine, or other professional associates such as Samuel Johnson or Samuel Richardson supplied it. But archival evidence indicates that Lady Isabella Finch, Lennox’s earliest patroness, was in contact with Birch in 1749, raising the question of whether she could have given Birch the poem. However, a different type of connection between Lennox and Birch is suggested by Lennox’s first novel, The Life of Harriot Stuart, written by Herself (1750, which mentions William Chillingworth, Isaac Barrow, and John Tillotson as theological influences. Lennox may have known of these three seventeenth-century divines through Birch’s biographical work on them.

  11. Structural analysis of heat-treated birch (Betule papyrifera) surface during artificial weathering

    Science.gov (United States)

    Huang, Xianai; Kocaefe, Duygu; Kocaefe, Yasar; Boluk, Yaman; Krause, Cornélia

    2013-01-01

    Effect of artificial weathering on the surface structural changes of birch (Betule papyrifera) wood, heat-treated to different temperatures, was studied using the fluorescence microscopy and the scanning electron microscopy (SEM). Changes in the chemical structure of wood components were analyzed by FTIR in order to understand the mechanism of degradation taking place due to heat treatment and artificial weathering. The results are compared with those of the untreated (kiln-dried) birch. The SEM analysis results show that the effect of weathering on the cell wall of the untreated birch surface is more than that of heat-treated samples. The FTIR spectroscopy results indicate that lignin is the most sensitive component of heat-treated birch to the weathering degradation process. Elimination of the amorphous and highly crystallised cellulose is observed for both heat-treated and untreated wood during weathering. It is also observed that heat treatment increases the lignin and crystallised cellulose contents, which to some extent protects heat-treated birch against degradation due to weathering.

  12. Computational verification of the Birch and Swinnerton-Dyer conjecture for individual elliptic curves

    Science.gov (United States)

    Grigorov, Grigor; Jorza, Andrei; Patrikis, Stefan; Stein, William A.; Tarnita, Corina

    2009-12-01

    We describe theorems and computational methods for verifying the Birch and Swinnerton-Dyer conjectural formula for specific elliptic curves over mathbb{Q} of analytic ranks 0 and 1 . We apply our techniques to show that if E is a non-CM elliptic curve over mathbb{Q} of conductor leq 1000 and rank 0 or 1 , then the Birch and Swinnerton-Dyer conjectural formula for the leading coefficient of the L -series is true for E , up to odd primes that divide either Tamagawa numbers of E or the degree of some rational cyclic isogeny with domain E . Since the rank part of the Birch and Swinnerton-Dyer conjecture is a theorem for curves of analytic rank 0 or 1 , this completely verifies the full conjecture for these curves up to the primes excluded above.

  13. Effect of different steam explosion conditions on methane potential and enzymatic saccharification of birch.

    Science.gov (United States)

    Vivekanand, Vivekanand; Olsen, Elisabeth F; Eijsink, Vincent G H; Horn, Svein J

    2013-01-01

    Birch (Betula pubescens) was steam exploded at 13 different conditions with temperatures ranging from 170 to 230 °C and residence times ranging from 5 to 15 min. Increasing severity in the pretreatment led to degradation of xylan and formation of pseudo-lignin. The effect of the pretreatments was evaluated by running enzymatic saccharification and anaerobic digestion followed by analysis of sugar and methane yields, respectively. Enzymatically released glucose increased with pretreatment severity up to 220 °C for 10 min and levels of solubilized glucose reached 97% of the theoretical maximum. The highest methane yield (369 mL gVS(-1)) was obtained at a severity factor of 4.5 and this yield was 1.8 times higher than the yield from untreated birch. Enzymatic glucose yields and methane yields were generally correlated. The results indicate that steam-exploded birch can be effectively converted to either glucose or methane.

  14. Effect of heating methods on drying quality of small-diameter birch lumbers

    Institute of Scientific and Technical Information of China (English)

    GUO Ming-hui; ZHAO Xi-ping; YAN Li

    2005-01-01

    Following a normal low temperature drying schedule, the small-diameter Birch lumbers ( 1 000mm ×45mm × 30mm) were dried with consecution-heats or intermittent-heating, visual drying defects (bow, crook,twist, check along grain and end check) were measured, and then statistical analyses were performed. It was found that the drying quality of small-diameter Birch lumbers could be improved with intermittent-heating, but the intermittent time should be prolonged. Prolonging intermittent time helped to weaken or even avoid wood distortion and drying checks. It wasn' t helpful in avoiding crook. The drying quality of small-diameter Birch lumbers with all kinds of drying methods reached the second class of the Chinese National Standard. The drying quality reached the first class of the Chinese National Standard with the intermittent-heating in the area of visual wood defects.

  15. DNA extraction of birch leaves by improved CTAB method and optimization of its ISSR system

    Institute of Scientific and Technical Information of China (English)

    PAN hua; YANG Chuan-ping; WEI Zhi-gang; JIANG Jing

    2006-01-01

    The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitable not only for genomic DNA extraction of birch but also for that of other plants. The purity of genomic DNA extracted by the multi-times STE-CTAB extraction method is higher than that by one time STE-CTAB method, and it does not need the process of RNase. The factors of influencing ISSR system were explored based on the genomic DNA of birch extracted by the two methods. The optimal conditions for ISSR system were determined as follows: cycles of denaturation for 30 s at 94℃, annealing for 30 s at 51 ℃, extension for 30 s at 72℃, and a final 7 min extension at 72 ℃.

  16. Bud flush phenology and nursery carryover effect of paper birch provenances

    Directory of Open Access Journals (Sweden)

    Dhar A

    2015-12-01

    Full Text Available Paper birch (Betula papyrifera Marsh is an ecologically valuable species with a broad geographic distribution across the North America. Its diversity, versatility and enduring nature make it an ideal candidate for a selective breeding program in this region. However, an understanding of the genecology of this species is fundamental to deploy it successfully. Ten paper birch provenances were collected from British Columbia (BC, Canada and northern Idaho (USA along elevational transects to determine whether observed bud flush phenology was due to genetics and /or environmental variation or their interaction. Seedlings were grown at three different nurseries: University of Idaho (46°44’N, Landing (50°17’N and Little Forestry (54°00’N and planted in a randomized single tree interlocking block design in three common gardens at Sandpoint, ID (48°13’N, Skimikin, BC (50°45’N and Red Rock, BC (53°45’N. Results indicate that variation in the timing of bud flush is a complex interaction among local genetic characteristics and environmental conditions of the growing site. Birch bud flush followed a general geographic trend where provenances at the southern common garden (Sandpoint required less time (Day of Year, DoY and fewer growing degree days (GDD compared to central (Skimikin and northern (Red Rock common gardens. Although there were significant differences in the timing of bud flush among provenances along an elevational gradient, none of the regions showed the expected linear elevational cline, trends were inconsistent. Further, birch bud flush was significantly influenced by nursery displacement effects in the initial year of establishment but disappeared within three years. These results provide an opportunity to characterize bud flush phenology of paper birch and would be useful for improving operational paper birch seed transfer programs in BC.

  17. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G.

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6 %-248 %. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  18. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States.

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6%-248%. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  19. [Antiviral activity of aqueous extracts of the birch fungus Inonotus obliquus on the human immunodeficiency virus].

    Science.gov (United States)

    Shibnev, V A; Garaev, T M; Finogenova, M P; Kalnina, L B; Nosik, D N

    2015-01-01

    Fractions of aqueous and water-alcohol extracts of the birch fungus Inonotus obliquus have antiviral effect against the human immunodeficiency virus type 1 (HIV-1). Antiviral properties of low toxic extracts were manifested in the concentration of 5.0 μg/ml upon simultaneous application with the virus in the lymphoblastoid cells culture MT-4. The extract of the birch fungus can be used for development of new antiviral drugs, inhibitors of HIV-replication when used both in the form of individual drugs and as a part of complex therapy. PMID:26182655

  20. Analysis of aspen-and-birch separated small woods’ vegetation in North Steppe of Ukraine

    Directory of Open Access Journals (Sweden)

    N. M. Nazarenko

    2010-09-01

    Full Text Available Conducted analysis of forest vegetation has allowed selecting and specifying classification and typological units of the aspen-and-birch separated small woods, which have statistically significant difference of ecotopic and coenotic parameters. Those parameters of studied forest ecosystems are characterised. Existence of the lines of hygrogenic and edaphogenic substitution, and succession rows are described. Phytoindication description of ecological factors’ pivotal conditions is presented. Driving factors determining parameters, structure and composition of the aspen-and-birch forest ecosystems are diminishing soil moisture, increasing annual temperatures amplitude and soil acidity.

  1. Study of the betulin enriched birch bark extracts effects on human carcinoma cells and ear inflammation

    Directory of Open Access Journals (Sweden)

    Dehelean Cristina A

    2012-11-01

    Full Text Available Abstract Background Pentacyclic triterpenes, mainly betulin and betulinic acid, are valuable anticancer agents found in the bark of birch tree. This study evaluates birch bark extracts for the active principles composition. Results New improved extraction methods were applied on the bark of Betula pendula in order to reach the maximum content in active principles. Extracts were analyzed by HPLC-MS, Raman, SERS and 13C NMR spectroscopy which revealed a very high yield of betulin (over 90%. Growth inhibiting effects were measured in vitro on four malignant human cell lines: A431 (skin epidermoid carcinoma, A2780 (ovarian carcinoma, HeLa (cervix adenocarcinoma and MCF7 (breast adenocarcinoma, by means of MTT assay. All of the prepared bark extracts exerted a pronounced antiproliferative effect against human cancer cell lines. In vivo studies involved the anti-inflammatory effect of birch extracts on TPA-induced model of inflammation in mice. Conclusions The research revealed the efficacy of the extraction procedures as well as the antiproliferative and anti-inflammatory effects of birch extracts.

  2. Shading and root-shoot relations in saplings of silver birch, pedunculate oak and beech

    NARCIS (Netherlands)

    Hees, van A.F.M.; Clerkx, A.P.P.M.

    2003-01-01

    Silver birch (Betula pendula Roth), pedunculate oak (Quercus robur L.) and beech (Fagus sylvatica L.) can regenerate successfully under a canopy of Scots pine (Pinus sylvestris L.). Shading reduces plant growth and modifies plant form, two related aspects. This study focuses on the effects of shadin

  3. Differential response of aspen and birch trees to heat stress under elevated carbon dioxide.

    Science.gov (United States)

    Darbah, Joseph N T; Sharkey, Thomas D; Calfapietra, Carlo; Karnosky, David F

    2010-04-01

    The effect of high temperature on photosynthesis of isoprene-emitting (aspen) and non-isoprene-emitting (birch) trees were measured under elevated CO(2) and ambient conditions. Aspen trees tolerated heat better than birch trees and elevated CO(2) protected photosynthesis of both species against moderate heat stress. Elevated CO(2) increased carboxylation capacity, photosynthetic electron transport capacity, and triose phosphate use in both birch and aspen trees. High temperature (36-39 degrees C) decreased all of these parameters in birch regardless of CO(2) treatment, but only photosynthetic electron transport and triose phosphate use at ambient CO(2) were reduced in aspen. Among the two aspen clones tested, 271 showed higher thermotolerance than 42E possibly because of the higher isoprene-emission, especially under elevated CO(2). Our results indicate that isoprene-emitting trees may have a competitive advantage over non-isoprene emitting ones as temperatures rise, indicating that biological diversity may be affected in some ecosystems because of heat tolerance mechanisms.

  4. Carbon and Nitrogen Transformations in Surface Soils Under Ermans Birch and Dark Coniferous Forests

    Institute of Scientific and Technical Information of China (English)

    DENG Xiao-Wen; HAN Shi-Jie; HU Yan-Ling; ZHOU Yu-Mei

    2009-01-01

    Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slopc of Changbai Mountains of Northeast China,to compare soil carbon (C) and nitrogen (N) transformations in the two forests.The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy.Soil samples were incubated aerobically at 20 ℃ and field capacity of 700 g kg-1 over a period of 27 weeks.The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest (P<0.05),whereas the cumulative C mineralization (as CO2 emission) in the dark coniferous forest exceeded that in the Ermans birch (P<0.05).Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest (P<0.05).The results suggested that differences of forest types could result in considerable change in soil C and N transformations.

  5. Antioxidants from slow pyrolysis bio-oil of birch wood: Application for biodiesel and biobased lubricants

    Science.gov (United States)

    Birch wood was slowly pyrolyzed to produce bio-oil and biochar. Slow pyrolysis conditions including reaction temperature, residence time, and particle size of the feed were optimized to maximize bio-oil yield. Particle size had an insignificant effect, whereas yields of up to 56% were achieved using...

  6. Impacts of Elevated Atmospheric CO2 and O3 on Paper Birch (Betula papyrifera: Reproductive Fitness

    Directory of Open Access Journals (Sweden)

    Joseph N. T. Darbah

    2007-01-01

    Full Text Available Atmospheric CO2 and tropospheric O3 are rising in many regions of the world. Little is known about how these two commonly co-occurring gases will affect reproductive fitness of important forest tree species. Here, we report on the long-term effects of CO3 and O3 for paper birch seedlings exposed for nearly their entire life history at the Aspen FACE (Free Air Carbon Dioxide Enrichment site in Rhinelander, WI. Elevated CO2 increased both male and female flower production, while elevated O3 increased female flower production compared to trees in control rings. Interestingly, very little flowering has yet occurred in combined treatment. Elevated CO2 had significant positive effect on birch catkin size, weight, and germination success rate (elevated CO2 increased germination rate of birch by 110% compared to ambient CO2 concentrations, decreased seedling mortality by 73%, increased seed weight by 17%, increased root length by 59%, and root-to-shoot ratio was significantly decreased, all at 3 weeks after germination, while the opposite was true of elevated O3 (elevated O3 decreased the germination rate of birch by 62%, decreased seed weight by 25%, and increased root length by 15%. Under elevated CO2, plant dry mass increased by 9 and 78% at the end of 3 and 14 weeks, respectively. Also, the root and shoot lengths, as well as the biomass of the seedlings, were increased for seeds produced under elevated CO2, while the reverse was true for seedlings from seeds produced under the elevated O3. Similar trends in treatment differences were observed in seed characteristics, germination, and seedling development for seeds collected in both 2004 and 2005. Our results suggest that elevated CO2 and O3 can dramatically affect flowering, seed production, and seed quality of paper birch, affecting reproductive fitness of this species.

  7. Allergens from birch pollen and pollen of the European chestnut share common epitopes.

    Science.gov (United States)

    Hirschwehr, R; Jäger, S; Horak, F; Ferreira, F; Valenta, R; Ebner, C; Kraft, D; Scheiner, O

    1993-09-01

    Type I allergy to pollen of the European chestnut (Castanea sativa) represents a major cause of pollinosis in (sub) Mediterranean areas. Using sera from 14 patients with established allergy to pollen of the European chestnut, 13/14 sera (92%) showed IgE-binding to a 22 kD protein, 2/14 (14%) displayed additional binding to a 14 kD protein and 1/14 (7%) bound only to the 14 kD protein of European chestnut pollen extract. Two monoclonal mouse antibodies, BIP 1 and BIP 4, directed against different epitopes of Bet v I (the major birch pollen allergen), and a rabbit antibody to recombinant birch profilin (rBet v II) were used to characterize the proteins of the European chestnut pollen. The recombinant birch pollen allergens, rBet v I and rBet v II (profilin) were employed to show common allergenic structures on proteins from both birch and European chestnut pollen by IgE-inhibition experiments. Despite the fact that the 22 kD protein displayed a higher molecular weight in comparison to the 17 kD major birch pollen allergen, Bet v I, we could demonstrate reactivity of both monoclonal antibodies, BIP 1 and BIP 4, with this protein. A complete inhibiton of IgE-binding to this 22 kD protein was shown by pre-incubating sera with purified recombinant Bet v I. In addition, the 14 kD protein could be identified by IgE-inhibition studies with recombinant Bet v II and by using a rabbit anti-profilin antibody as the profilin from pollen of the European chestnut.

  8. Glutathione-S-Transferase: A Minor Allergen in Birch Pollen due to Limited Release from Hydrated Pollen

    OpenAIRE

    Stephan Deifl; Christian Zwicker; Eva Vejvar; Claudia Kitzmüller; Gabriele Gadermaier; Birgit Nagl; Susanne Vrtala; Peter Briza; Zlabinger, Gerhard J.; Beatrice Jahn-Schmid; Fatima Ferreira; Barbara Bohle

    2014-01-01

    Background Recently, a protein homologous to glutathione-S-transferases (GST) was detected in prominent amounts in birch pollen by proteomic profiling. As members of the GST family are relevant allergens in mites, cockroach and fungi we investigated the allergenic relevance of GST from birch (bGST). Methodology bGST was expressed in Escherichia coli, purified and characterized by mass spectrometry. Sera from 217 birch pollen-allergic patients were tested for IgE-reactivity to bGST by ELISA. T...

  9. Biogeography of Alaska paper birch (Betula neoalaskana): latitudinal patterns in chemical defense and plant architecture.

    Science.gov (United States)

    Stevens, Michael T; Brown, Sarah C; Bothwell, Helen M; Bryant, John P

    2016-02-01

    The latitudinal herbivory-defense hypothesis (LHDH) predicts that plants near the equator will be more heavily defended against herbivores than are plants at higher latitudes. Although this idea is widely found in the literature, recent studies have called this biogeographic pattern into question. We sought to evaluate the LHDH in a high-latitude terrestrial ecosystem where fire and mammalian herbivores may contribute to selection for higher levels of defensive chemistry. To address this objective, we collected seeds of Alaska paper birch (Betula neoalaskana) from nine locations along two north-south transects between 55 degrees N and 62 degrees N latitudes in western, interior Canada. The birch seeds were planted in pots in a common garden in Madison, Wisconsin, USA. From the resulting seedlings, we determined levels of chemical defense by assessing the density of resin glands, which have been shown to be negatively correlated with browsing. To assess plant architectural traits such as height, mean individual leaf area, and root-to-shoot ratio, we harvested a subset of the birch seedlings. Further, we used these traits to examine growth-defense trade-offs. Contrary to the LHDH, we found a positive correlation between chemical defense and latitude. Investigating relationships with fire, we found a strong positive correlation between resin gland density and percentage of area annually burned (PAAB) around each collection location and also between PAAB and latitude. Additionally, birch seedlings originating from higher latitudes were shorter, smaller-leaved, and rootier than their lower-latitude counterparts. Growth-defense trade-offs were observed in negative correlations between resin gland density and height and leaf size. Seedlings with higher resin gland densities also allocated less biomass to shoots and more to roots. These results further call into question the LHDH and provide specific information about latitudinal trends in plant defense at high, northern

  10. The results of fluorescence spectrums of oak and birch leaves investigation from the 30-km influenced zone of Chernobyl NPP

    International Nuclear Information System (INIS)

    The results of a long-term research of laser induced fluorescence of foliage tree' leaves (oak, birch) that grow in different conditions of radioactive pollution (30-km zone of Chernobyl NPP) are presented

  11. A novel alkaline oxidation pretreatment for spruce, birch and sugar cane bagasse.

    Science.gov (United States)

    Kallioinen, Anne; Hakola, Maija; Riekkola, Tiina; Repo, Timo; Leskelä, Markku; von Weymarn, Niklas; Siika-aho, Matti

    2013-07-01

    Alkaline oxidation pretreatment was developed for spruce, birch and sugar cane bagasse. The reaction was carried out in alkaline water solution under 10 bar oxygen pressure and at mild reaction temperature of 120-140°C. Most of the lignin was solubilised by the alkaline oxidation pretreatment and an easily hydrolysable carbohydrate fraction was obtained. After 72 h hydrolysis with a 10 FPU/g enzyme dosage, glucose yields of 80%, 91%, and 97%, for spruce, birch and bagasse, respectively, were achieved. The enzyme dosage could be decreased to 4 FPU/g without a major effect in terms of the hydrolysis performance. Compared to steam explosion alkaline oxidation was found to be significantly better in the conditions tested, especially for the pretreatment of spruce. In hydrolysis and fermentation at 12% d.m. consistency an ethanol yield of 80% could be obtained with both bagasse and spruce in 1-3 days.

  12. EFFECT OF BIRCH KRAFT PULP PRIMARY FINES ON BLEACHING AND SHEET PROPERTIES

    Directory of Open Access Journals (Sweden)

    Sari Anneli Asikainen

    2010-08-01

    Full Text Available By removing the primary fines from an oxygen-delignified mill birch pulp, a fiber fraction was obtained having low metals content and no extractives. After DEDeD bleaching the fiber fraction had somewhat higher brightness and better brightness stability than the birch pulp containing the primary fines. The fines fraction was enriched with lignin, extractives, xylan, and metals. Bleaching the fines fraction in a QQP sequence did not affect the extractives, whereas a ZeQP sequence clearly reduced the extractives content. In a biorefinery concept, the fines fraction could be utilized as a source of xylan, fatty acids, sterols, and betulinol. Another possibility is to use the fines fraction unbleached or separately bleached as a bonding material in various fiber furnishes.

  13. Effect of Different Pretreatment Methods on Birch Outer Bark: New Biorefinery Routes.

    Science.gov (United States)

    Karnaouri, Anthi; Rova, Ulrika; Christakopoulos, Paul

    2016-01-01

    A comparative study among different pretreatment methods used for the fractionation of the birch outer bark components, including steam explosion, hydrothermal and organosolv treatments based on the use of ethanol/water media, is reported. The residual solid fractions have been characterized by ATR-FTIR, (13)C-solid-state NMR and morphological alterations after pretreatment were detected by scanning electron microscopy. The general chemical composition of the untreated and treated bark including determination of extractives, suberin, lignin and monosaccharides was also studied. Composition of the residual solid fraction and relative proportions of different components, as a function of the processing conditions, could be established. Organosolv treatment produces a suberin-rich solid fraction, while during hydrothermal and steam explosion treatment cleavage of polysaccharide bonds occurs. This work will provide a deeper fundamental knowledge of the bark chemical composition, thus increasing the utilization efficiency of birch outer bark and may create possibilities to up-scale the fractionation processes.

  14. Proteomic Analysis of Responsive Proteins Induced in Japanese Birch Plantlet Treated with Salicylic Acid

    Directory of Open Access Journals (Sweden)

    Hiromu Suzuki

    2014-07-01

    Full Text Available The present study was performed to unravel the mechanisms of systemic acquired resistance (SAR establishment and resistance signaling pathways against the canker-rot fungus (Inonotus obliquus strain IO-U1 infection in Japanese birch plantlet No.8. Modulation of protein-profile induced by salicylic acid (SA-administration was analyzed, and SA-responsive proteins were identified. In total, 5 specifically expressed, 3 significantly increased, and 3 significantly decreased protein spots were identified using liquid chromatography/tandem mass spectrometry (LC/MS/MS and the sequence tag method. These proteins were malate dehydrogenase, succinate dehydrogenase, phosphoglycerate kinase, diaminopimalate decarboxylase, arginase, chorismate mutase, cyclophilin, aminopeptidase, and unknown function proteins. These proteins are considered to be involved in SAR-establishment mechanisms in the Japanese birch plantlet No 8.

  15. Reduced VOC emissions from birch sawdust dried in a steam drier at atmospheric pressure

    Energy Technology Data Exchange (ETDEWEB)

    Granstrom, K.M. [Karlstad Univ., Karlstad (Sweden). Dept. of Environmental and Energy Systems, Div. of Engineering Sciences, Physics and Mathematics

    2003-07-01

    A study was conducted to determine the quantity and composition of volatile organic compounds (VOC) emitted from birch sawdust when it is dried in a steam dryer at atmospheric pressure. Sawdust is commonly dried for production of wood pellets and particle board. VOCs, which are emitted during the drying process, contribute to the formation of ground level ozone and other hazardous photochemical oxidants. The chemical composition of VOCs emitted from drying softwood is different from that emitted during the drying of hardwoods such as birch. The dryer used in this study was a pilot scale spouted bed in continuous operation. Sawdust was dried to different moisture contents. Two drying medium temperatures (170 degrees C and 200 degrees C) were applied. The results were then compared to the emissions from softwoods dried under similar conditions.

  16. Effect of Different Pretreatment Methods on Birch Outer Bark: New Biorefinery Routes

    Directory of Open Access Journals (Sweden)

    Anthi Karnaouri

    2016-03-01

    Full Text Available A comparative study among different pretreatment methods used for the fractionation of the birch outer bark components, including steam explosion, hydrothermal and organosolv treatments based on the use of ethanol/water media, is reported. The residual solid fractions have been characterized by ATR-FTIR, 13C-solid-state NMR and morphological alterations after pretreatment were detected by scanning electron microscopy. The general chemical composition of the untreated and treated bark including determination of extractives, suberin, lignin and monosaccharides was also studied. Composition of the residual solid fraction and relative proportions of different components, as a function of the processing conditions, could be established. Organosolv treatment produces a suberin-rich solid fraction, while during hydrothermal and steam explosion treatment cleavage of polysaccharide bonds occurs. This work will provide a deeper fundamental knowledge of the bark chemical composition, thus increasing the utilization efficiency of birch outer bark and may create possibilities to up-scale the fractionation processes.

  17. Influence of Biomass Pretreatment Process Time on Furfural Extraction from Birch Wood

    Science.gov (United States)

    Brazdausks, Prans; Puke, Maris; Vedernikovs, Nikolajs; Kruma, Irena

    2013-12-01

    Furfural is a biomass derived-chemical that can be used to replace petrochemicals. In this study, dilute sulphuric acid hydrolysis was used for hemicelluloses secession from birch wood. The reaction was investigated at different biomass treatment times (10-90 min, increasing it by 10 min). We found that the greatest amount of furfural 1.4-2.6%, which is 9.7-17.7% from theoretical possible yield, was formed in the first 30 min of the beginning of birch wood pentoses monosaccharide dehydration, but the greatest yield of furfural 10.3%, which is 70.0% from the theoretical yield, can be obtained after 90 min. Given that furfural yield generally does not exceed 50% from the theoretical amount, the result can be considered as very good.

  18. Analysis and identification of SCAR molecular markers associated with birch fiber length trait

    Institute of Scientific and Technical Information of China (English)

    WANG Dan; WEI Zhi-gang; YANG Chuan-ping; LIU Guan-jun

    2008-01-01

    The fiber length trait (FLT) of 538 individuals from nature birch population in Maorshan region,Heilongjang,China were measured,of which 100 individuals were selected as representative variety of correlated fragments screening with random amplified polymorphism DNA (RAPD) technique.In total of 20 RAPD primers were tested through multiple regression analysis between amplified strip and the character behaviors,and a correlative segment BFLR-16 was obtained.The correlation coefficient between BFLI-16 and FLT was 0.6144,with the significant level of 1%.BFLI-16 was then cloned,sequenced and transformed into SCAR marker.The percentage of identifying long fiber birches by this SCAR was more than 92.The result indicates that the SCAR markers has high specificity for the long fiber individuals and is highly linked with the gene controlling the character of fiber length,and its existence is significantly correlative with the increase in the fiber length.

  19. EFFECTS OF HOT WATER EXTRACTION IN A BATCH REACTOR ON THE DELIGNIFICATION OF BIRCH WOOD

    OpenAIRE

    Marc Borrega; Kaarlo Nieminen; Herbert Sixta

    2011-01-01

    The amount of residual lignin in birch wood after a hot water extraction in a batch reactor was investigated as a function of extraction temperature and time. A kinetic model fitting the experimental data was then developed to explain delignification of wood during a hot water treatment. Results showed that delignification kinetics involves simultaneous degradation and condensation reactions, with degradation of lignin being much faster than its condensation. Native lignin in wood was success...

  20. Proteomic Analysis of Responsive Proteins Induced in Japanese Birch Plantlet Treated with Salicylic Acid

    OpenAIRE

    Suzuki, Hiromu; Takashima, Yuya; Ishiguri, Futoshi; Yoshizawa, Nobuo; Yokota, Shinso

    2014-01-01

    The present study was performed to unravel the mechanisms of systemic acquired resistance (SAR) establishment and resistance signaling pathways against the canker-rot fungus (Inonotus obliquus strain IO-U1) infection in Japanese birch plantlet No.8. Modulation of protein-profile induced by salicylic acid (SA)-administration was analyzed, and SA-responsive proteins were identified. In total, 5 specifically expressed, 3 significantly increased, and 3 significantly decreased protein spots were i...

  1. Proteomic Analysis of Responsive Proteins Induced in Japanese Birch Plantlet Treated with Salicylic Acid

    OpenAIRE

    Hiromu Suzuki; Yuya Takashima; Futoshi Ishiguri; Nobuo Yoshizawa; Shinso Yokota

    2014-01-01

    The present study was performed to unravel the mechanisms of systemic acquired resistance (SAR) establishment and resistance signaling pathways against the canker-rot fungus (Inonotus obliquus strain IO-U1) infection in Japanese birch plantlet No.8. Modulation of protein-profile induced by salicylic acid (SA)-administration was analyzed, and SA-responsive proteins were identified. In total, 5 specifically expressed, 3 significantly increased, and 3 significantly decreased protein spots were ...

  2. Preliminary tests with a birch wood pellets up-draft air gasifier

    OpenAIRE

    Grimm, Alejandro; Suarez, José; Björnbom, Emilia; Zanzi Vigouroux, Rolando

    2004-01-01

    In Sweden and Cuba a variety of biomass have being investigated for energyconversion through termochemical processes into solid, liquids and gaseous products. Biomass gasification in fixed bed seem to be attractive option for the conversion ofagricultural and forest residues into gases suitable for use as alternative fuel in gasengines in rural areas, heat or electricity production. This paper discusses the performance characteristics of a up - draft gasifier withBirch wood pellets. The bench...

  3. Ground bryophyte diversity in secondary birch forests in western Sichuan, China

    OpenAIRE

    Xiaoli Yan; Weikai Bao

    2011-01-01

    Secondary birch (Betula spp.) forest is an important vegetation type in western Sichuan, China. These forests have naturally regenerated from primary fir (Abies spp.) forests after clear-cutting. However,little is known about ground bryophyte species composition and community structure during this succession sequence. In our study, we sampled three plots in 9-, 22-, and 42-year old secondary forests, and a primary fir forest, respectively, in Jinchuan County. We found that bryophyte coverage ...

  4. Analysis of aspen-and-birch separated small woods’ vegetation in North Steppe of Ukraine

    OpenAIRE

    N. M. Nazarenko; I. M. Loza

    2010-01-01

    Conducted analysis of forest vegetation has allowed selecting and specifying classification and typological units of the aspen-and-birch separated small woods, which have statistically significant difference of ecotopic and coenotic parameters. Those parameters of studied forest ecosystems are characterised. Existence of the lines of hygrogenic and edaphogenic substitution, and succession rows are described. Phytoindication description of ecological factors’ pivotal conditions is presented. D...

  5. Individual tree mortality of silver birch (Betula pendula Roth in Estonia

    Directory of Open Access Journals (Sweden)

    Maleki K

    2016-08-01

    Full Text Available The functioning of complex forest ecosystems is intimately related to their structural properties. Tree mortality is a major driver of forest stand dynamics and therefore plays an important role in the formation of forest structure. Data from the Estonian Network of Forest Research Plots (ENFRP was used to estimate the mortality probability of silver birch trees (Betula pendula Roth by using logistic models. In this study several spatial and non-spatial variables were tested to determine the most important mortality explanatory factors. Additionally, thinning variables were defined and implemented into the mortality models, to examine whether thinning practices could modify the stand structure and density, then leading to a lower mortality rate. The results of this study showed that tree mortality models that included either a five-year diameter growth rate (id5 as a measure of tree vitality, or the tree relative diameter (drel as a measure of competition, or both these two variables, were substantially better than any models not including these variables. In addition, any measures of spatial aggregation (agg and species proportion (sp within the zone of influence markedly improved the model predictions, though the mortality probability of trees declined where there was higher aggregation and species mixture. Our results also suggested that if thinning were conducted around the birch trees, depending on the thinning intensity, the number of neighbors is effectively reduced, and consequently the competition load within the influence zone decreases, leading to healthier growth and lower mortality rates of the shade-intolerant birch trees. We thus recommend to adopt thinning regimes in mixed forest stands to foster tree species diversity, and at the same time provide adequate growing space for birch trees within the stands. This will improve the forest structure and increase the adaptive capacity of forests, which is increasingly important under

  6. Shelf life extension and sensory evaluation of birch tree sap using chemical preservatives

    Directory of Open Access Journals (Sweden)

    Maciej Bilek

    2016-10-01

    Full Text Available The aim of this study was to assess the stability of the birch tree sap, depending on the addition and concentration of two chemical factors, ie. potassium sorbate and acids: malic, citric or lactic. As in our previous studies we found that the optimal physical parameter to assess the stability of birch sap is turbidity measurement, we used turbidimeter for estimate the effectiveness of shelf life extending. Sensory evaluation was carried out by university sensory panel with 8 skilled people (students and teachers with pre-selection and basic training of sensory methodology. On the other hand artificial perception measurements were realized by electronic nose. Birch tree sap stability without addition of preservatives, both room temperature and refrigerated, is less than three days. The effectiveness of preservation of birch tree sap depends on the concentration of acids. Independently of storage temperature, samples that received stability during the whole one-month storage period, were those with potassium sorbate and three acids in the highest concentrations, ie. malic acid at 0.3%, citric acid at 0.5% and lactic acid at 0.5%. Unfortunately, concentrations of acids, which allow extension of shelf life at least for one month in a room temperature, are characterized by the worst sensory evaluation rating. Thus, they should be corrected by the use of additives for improving the flavor, such as fruit syrups or herbal extracts. On the other hand, additionally storage in a refrigerated conditions allows one-month-stability for the sample with the highest sensory evaluation rating, ie. with the addition of lactic acid at 0.1% and potassium sorbate, which taste not need to be corrected.

  7. Mountain birch – potentially large source of sesquiterpenes into high latitude atmosphere

    Directory of Open Access Journals (Sweden)

    A. Arneth

    2009-11-01

    Full Text Available Emissions of volatile organic compounds (VOCs from mountain birches were measured in Abisko, northern Sweden. Mountain birches make up the majority of the tree biomass in Scandinavian high latitudes, a region subject to significant climate warming. The measurements were carried out in two growing seasons. The emissions of four branches, each from a different individual tree, were measured in June–August 2006 and one of them again in July 2007. The measurements were conducted using a dynamic flow through chamber covered with Teflon film. The studied mountain birches were found to emit substantial amounts of linalool, monoterpenes and sesquiterpenes. The monoterpene emission was dominated by sabinene. The magnitude and composition of the sesquiterpene emission changed dramatically between the years. For example, the average α-farnesene emission potential in 2006 was almost 2600 ng gdw−1 h−1 (3.5 pmol gdw−1 s−1 while in 2007 α-farnesene was not detected at all. Also the emissions of other sesquiterpenes decreased in 2007 to a fraction of that in 2006. One possible explanation for the change in emissions is the herbivory damage that occurred in the area in 2004. Herbivory is known to enhance the emissions of sesquiterpenes, especially those of α-farnesene, and the effect may last for several years.

  8. Drying and wetting of Mediterranean soils stimulates decomposition and carbon dioxide emission: the "Birch effect".

    Science.gov (United States)

    Jarvis, Paul; Rey, Ana; Petsikos, Charalampos; Wingate, Lisa; Rayment, Mark; Pereira, João; Banza, João; David, Jorge; Miglietta, Franco; Borghetti, Marco; Manca, Giovanni; Valentini, Riccardo

    2007-07-01

    Observations on the net carbon exchange of forests in the European Mediterranean region, measured recently by the eddy covariance method, have revived interest in a phenomenon first characterized on agricultural and forest soils in East Africa in the 1950s and 1960s by H. F. Birch and now often referred to as the "Birch effect." When soils become dry during summer because of lack of rain, as is common in regions with Mediterranean climate, or are dried in the laboratory in controlled conditions, and are then rewetted by precipitation or irrigation, there is a burst of decomposition, mineralization and release of inorganic nitrogen and CO(2). In forests in Mediterranean climates in southern Europe, this effect has been observed with eddy covariance techniques and soil respiration chambers at the stand and small plot scales, respectively. Following the early work of Birch, laboratory incubations of soils at controlled temperatures and water contents have been used to characterize CO(2) release following the rewetting of dry soils. A simple empirical model based on laboratory incubations demonstrates that the amount of carbon mineralized over one year can be predicted from soil temperature and precipitation regime, provided that carbon lost as CO(2) is taken into account. We show that the amount of carbon returned to the atmosphere following soil rewetting can reduce significantly the annual net carbon gain by Mediterranean forests. PMID:17403645

  9. Mountain birch – potentially large source of sesquiterpenes into high latitude atmosphere

    Directory of Open Access Journals (Sweden)

    S. Haapanala

    2009-06-01

    Full Text Available Emissions of volatile organic compounds (VOCs from mountain birches were measured in Abisko, northern Sweden. Mountain birches make up majority of the tree biomass in Scandinavian high latitudes, area subject to significant climate warming. The measurements were carried out in two growing seasons. The emissions of a branch from four individual trees were measured in June–August 2006 and one of them again in July 2007. The measurements were conducted using a dynamic flow through chamber covered with Teflon film. The studied mountain birches were found to emit substantial amounts of linalool, monoterpenes and sesquiterpenes. The monoterpene emission was dominated by sabinene. The magnitude and composition of sesquiterpene emission changed dramatically between the years. For example, the average α-farnesene emission in 2006 was almost 2000 ng gdw−1 h−1 while in 2007 the emission of α-farnesene was negligible. Also the emissions of other sesquiterpenes decreased in 2007 to a fraction of that in 2006. One possible explanation for the change in emissions is the herbivory damage that occurred in the area in 2004. Herbivory is known to enhance the emissions of sesquiterpenes, especially those of α-farnesene, and the effect may last several years.

  10. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    Eric C. Xu; Yajun Zhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes.The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  11. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    EricC.Xu; YajunZhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes. The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  12. Growth of Scots Pine and Silver Birch Seedlings on Different Nursery Container Media

    Directory of Open Access Journals (Sweden)

    Fahrettin TILKI

    2014-12-01

    Full Text Available Peat has been the most common growing medium in tree nurseries, either alone or as a component of growing media mixes. However, as a result of increasing costs and decreasing amount of peat, seedling-growers are seeking more local growing medium components. In this study, container seedlings of Scots pine (Pinus sylvestris L. and silver birch (Betula pendula Roth were grown in pure peat and peat mixtures containing perlite and zeolite.  Physical parameters (height, shoot diameter, root dry weight, shoot dry weight, total dry weight were measured along with several morphological parameters (sturdiness quotient, height/diameter, shoot/root ratio. The zeolite additive in peat changed some media properties, and significant relation was established between some morphological attributes of seedlings and some medium properties in both species. On average, the seedlings grew best in pure peat, but zeolite additions to peat did not affect some morphological parameters negatively. The results suggest that zeolite has potential to be used as a component of peat based growing medium mixtures, and addition of zeolite to peat container medium in proportions of 10% by volume in Scots pine and up to 20% in silver birch was shown to be a feasible material for growing Scots pine and silver birch seedlings.

  13. Identification of SSR loci in Betula luminifera using birch EST data

    Institute of Scientific and Technical Information of China (English)

    LU Yong-quan; LI Hai-ying; JIA Qing; HUANG Hua-hong; TONG Zai-kang

    2011-01-01

    Expressed sequence tags (ESTs) are generated from single-pass sequencing of randomly picked cDNA clones and can be used for development of simple sequence repeat (SSR) markers or microsatellites.However,EST databases have been developed for only a small number of species.This paper provides a case study of the utility of freely available birch EST reources for the development of markers necessary for the genetic analysis of Betula luminifera.Based on birch EST data,primers for 80 EST-SSR candidate loci were developed and tested in birch.Of these,59 EST-SSR loci yielded single,stable and clear PCR products.We then tested the utility of those 59 markers in B.luminifera.The results showed 28 (47.6%) yielded stable and clear PCR products for at least one B.luminifera genotype.In addition,this study describes a rapid and inexpensive alternative for the development of SSRs in species with scarce available sequence data.

  14. EFFECT OF THERMAL TREATMENT ON THE CHEMICAL COMPOSITION AND MECHANICAL PROPERTIES OF BIRCH AND ASPEN

    Directory of Open Access Journals (Sweden)

    Duygu Kocaefe

    2008-05-01

    Full Text Available The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The wood structure changes due to decomposition of hemicelluloses, ramification of lignin, and crystallization of cellulose. The wood becomes less hygroscopic. These changes improve the dimensional stability of wood, increase its resistance to micro-organisms, darken its color, and modify its hardness. However, wood also might loose some of its elasticity. Consequently, the heat treatment conditions have to be optimized. Therefore, it is important to understand the transformation of the chemical structure of wood caused by the treatment. In this study, the modification of the surface composition of the wood was followed with Fourier transform infrared spectroscopy (FTIR and inverse gas chromatography (IGC under different experimental conditions. The effect of maximum treatment temperatures on the chemical composition of Canadian birch and aspen as well as the correlations between their chemical transformation and different mechanical properties are presented. FTIR analysis results showed that the heat treatment affected the chemical composition of birch more compared to that of aspen. The results of IGC tests illustrated that the surfaces of the aspen and birch became more basic with heat treatment. The mechanical properties were affected by degradation of hemicellulose, ramification of lignin and cellulose crystallization.

  15. The safety and efficacy of subcutaneous birch pollen immunotherapy - a one-year, randomised, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Poulsen, L K; Jacobi, H H;

    2002-01-01

    BACKGROUND: There is only very limited documentation of the efficacy and safety of high-dose subcutaneous birch pollen immunotherapy (IT) in double-blind, placebo-controlled (DBPC) studies. Birch pollen is a major cause of allergic morbidity in northern Europe and in eastern parts of North America....... METHODS: Thirty-five patients with severe rhinoconjunctivitis (hay fever) to birch pollen were allocated to double-blinded clustered IT with a depot birch pollen extract (Betula verrucosa) or placebo injections. Seven patients in each group had concomitant self-reported seasonal asthma. Treatment...... antihistamines (P effects at the same level as placebo...

  16. The safety and efficacy of subcutaneous birch pollen immunotherapy - a one-year, randomised, double-blind, placebo-controlled study

    DEFF Research Database (Denmark)

    Bødtger, U; Poulsen, Lars K.; Jacobi, H H;

    2002-01-01

    There is only very limited documentation of the efficacy and safety of high-dose subcutaneous birch pollen immunotherapy (IT) in double-blind, placebo-controlled (DBPC) studies. Birch pollen is a major cause of allergic morbidity in northern Europe and in eastern parts of North America.......There is only very limited documentation of the efficacy and safety of high-dose subcutaneous birch pollen immunotherapy (IT) in double-blind, placebo-controlled (DBPC) studies. Birch pollen is a major cause of allergic morbidity in northern Europe and in eastern parts of North America....

  17. Changes in crown architecture as a strategy of mountain birch for survival in habitats disturbed by pollution.

    Science.gov (United States)

    Zverev, Vitali; Kozlov, Mikhail V; Zvereva, Elena L

    2013-02-01

    Although trees in polluted areas often exhibit modified growth habits, the immediate causes of changes in crown architecture and their consequences for persistence of plant populations in disturbed habitats are not well understood. We compared individuals of mountain birch, Betula pubescens ssp. czerepanovii, growing in severely disturbed habitats (industrial barrens) surrounding a nickel-copper smelter in north-western Russia, with birches growing in unpolluted habitats. They were found to have shorter heights, a shrubby growth habit, lower depth/width and surface/foliar mass ratios of the crown, higher numbers of dead branches and twisted trunks and higher branching resulting from increased numbers of long shoots and more densely spaced buds than individuals in unpolluted forests. The increased production of long shoots was enabled by their formation not only from the axillary buds of previous-year long shoots but also from the apical buds of short shoots. These latter long shoots develop in the inner part of the crown, thus increasing the crown density. Additionally, birches from industrial barrens better compensated for mechanical damage, such as trunk/shoot removal, compared to birches from unpolluted forest and mountain tundra habitats, presumably due to the larger number of buds formed annually. The specific crown architecture of these birches can be explained by the direct effects of pollution combined with changes in microclimate due to pollution-induced forest decline. The seed progenies of birches from an industrial barren reared in a benign environment produced higher numbers of long shoots than seedlings from other habitats, suggesting that adaptive changes in crown architecture are partially shaped by the selection imposed by long-term pollution impacts. Nearly spherical and compact crowns minimise the impacts of unfavourable environmental conditions on trees and are therefore adaptive. We concluded that the development of specific crown architecture

  18. Characterization of PR-10 genes from eight Betula species and detection of Bet v 1 isoforms in birch pollen

    Directory of Open Access Journals (Sweden)

    van't Westende Wendy PC

    2009-03-01

    Full Text Available Abstract Background Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MSE was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome. Results All examined birch species contained several PR-10 genes. In total, 134 unique sequences were recovered. Sequences were attributed to different genes or pseudogenes that were, in turn, ordered into seven subfamilies. Five subfamilies were common to all birch species. Genes of two subfamilies were expressed in pollen, while each birch species expressed a mixture of isoforms with at least four different isoforms. Isoforms that were similar to isoforms with a high IgE-reactivity (Bet v 1a = PR-10.01A01 were abundant in all species except B. lenta, while the hypoallergenic isoform Bet v 1d (= PR-10.01B01 was only found in B. pendula and its closest relatives. Conclusion Q-TOF LC-MSE allows efficient screening of Bet v 1 isoforms by determining the presence and relative abundance of these isoforms in pollen. B. pendula contains a Bet v 1-mixture in which isoforms with a high and low IgE-reactivity are both abundant. With the possible exception of B. lenta, isoforms identical or very similar to those with a high IgE-reactivity were found in the pollen proteome of all examined birch species. Consequently, these species are also predicted to be allergenic with regard to Bet v 1 related allergies.

  19. High environmental ozone levels lead to enhanced allergenicity of birch pollen.

    Directory of Open Access Journals (Sweden)

    Isabelle Beck

    Full Text Available BACKGROUND: Evidence is compelling for a positive correlation between climate change, urbanisation and prevalence of allergic sensitisation and diseases. The reason for this association is not clear to date. Some data point to a pro-allergenic effect of anthropogenic factors on susceptible individuals. OBJECTIVES: To evaluate the impact of urbanisation and climate change on pollen allergenicity. METHODS: Catkins were sampled from birch trees from different sites across the greater area of Munich, pollen were isolated and an urbanisation index, NO2 and ozone exposure were determined. To estimate pollen allergenicity, allergen content and pollen-associated lipid mediators were measured in aqueous pollen extracts. Immune stimulatory and modulatory capacity of pollen was assessed by neutrophil migration assays and the potential of pollen to inhibit dendritic cell interleukin-12 response. In vivo allergenicity was assessed by skin prick tests. RESULTS: The study revealed ozone as a prominent environmental factor influencing the allergenicity of birch pollen. Enhanced allergenicity, as assessed in skin prick tests, was mirrored by enhanced allergen content. Beyond that, ozone induced changes in lipid composition and chemotactic and immune modulatory potential of the pollen. Higher ozone-exposed pollen was characterised by less immune modulatory but higher immune stimulatory potential. CONCLUSION: It is likely that future climate change along with increasing urbanisation will lead to rising ozone concentrations in the next decades. Our study indicates that ozone is a crucial factor leading to clinically relevant enhanced allergenicity of birch pollen. Thus, with increasing temperatures and increasing ozone levels, also symptoms of pollen allergic patients may increase further.

  20. Adaptive Responses of Birch-Leaved Pear (Pyrus betulaefolia Seedlings to Salinity Stress

    Directory of Open Access Journals (Sweden)

    Qiang Sheng WU

    2009-06-01

    Full Text Available One-year-old birch-leaved pear (Pyrus betulaefolia Bunge seedlings were subjected to 0, 50, 100, 150, and 200 mmol/L NaCl solutions for 27 days in order to study the effects of salinity stress on photosynthesis, ion accumulation and enzymatic and non-enzymatic scavenging of reactive oxygen species in the seedlings. The research was performed in a greenhouse using potted trees. Salinity stress reduced photosynthetic rates, stomatal conductance and water use efficiency of leaves of the pear seedlings, but increased transpiration rates and leaf temperature. Hydrogen peroxide and superoxide anion radical contents increased with increasing NaCl concentrations, a phenomena also observed for malondialdehyde, suggesting that leaves of the pear seedlings suffered from oxidative injury. Superoxide dismutase (SOD and catalase (CAT activities quickly responded by increasing when the pear seedlings were subjected to salinity stress. Total protein content in leaves of the seedlings was restrained by salinity stress, whereas ascorbate content increased. Salinity stress reduced glutathione content once the birch-leaved pear seedlings were exposed to a low level (50 or 100 mmol/L of NaCl, whereas a high level (150 or 200 mmol/L NaCl of salinity stress stimulated the accumulation of glutathione. Salinity stress increased the accumulation of Na+, Cl-, K+ and Mg2+ in the seedlings, but reduced Ca2+ levels and the ratio of other ions to Na+ except K+/Na+ under 50 mmol/L NaCl conditions. This suggests that leaves of birch-leaved pear seedlings possess the capacity for salt exclusion only under 50 mmol/L NaCl conditions, and Ca2+ does not play a fundamental role as a secondary messenger under salinity stress conditions.

  1. Synthesis and characterization of birch wood xylan succinoylated in 1-n-butyl-3-methylimidazolium chloride

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Plackett, David

    2011-01-01

    The chemical modification of birch wood xylan was undertaken in the ionic liquid 1-n-butyl-3-methylimidazolium chloride (C4mimCl) using three different long-chain succinic anhydrides: n-octenyl succinic anhydride (n-OSA), n-dodecenyl succinic anhydride (n-DDSA) and n-octadecenyl succinic anhydride...... analysis of the modified and native xylans showed a slight lowering of thermal stability with functionalization. Contact angle measurements on spin-coated surfaces of modified xylan films showed a significant increase in hydrophobicity with the introduction of the alkenyl-functionalized succinic anhydride...

  2. Diagnostic value of scratch-chamber test, skin prick test, histamine release and specific IgE in birch-allergic patients with oral allergy syndrome to apple

    DEFF Research Database (Denmark)

    Osterballe, M; Scheller, R; Stahl Skov, P;

    2003-01-01

    BACKGROUND: The aim of the study was to examine the diagnostic value of skin prick test (SPT), scratch-chamber test (SCT), histamine release (HR) and specific immunoglobulin E (IgE) in birch-allergic patients with oral allergy syndrome to apple. METHODS: Ten birch-allergic patients with oral...

  3. Modeling the 'Birch Effect' Using a Microbial Enzyme Based Soil Organic Carbon Decomposition and Gas Transport Model

    Science.gov (United States)

    Niu, G.; Zhang, X.; Barron-Gafford, G.; Pavao-zuckerman, M.

    2013-12-01

    Soil respiration pulses in response to pulsed wetting ('Birch effect'; Birch 1958) have long been observed from laboratory and field experiments. The Birch effect produces more CO2 efflux and sustains greater microbial biomass than constantly moist soils. Various mechanisms causing the effect have been proposed. However, the exact mechanism underlying the Birch effect is not clear, and thus most models are not able to simulate this effect. We have recently developed a microbial enzyme based decomposition and gas transport model. The model integrates the most recent advances in the understanding of critical processes, including enzyme-catalyzed degradation of soil organic carbon (SOC) to dissolved organic carbon (DOC), acclimation of carbon use efficiency (CUE) for the uptake of DOC by microbes, and diffusive and convective transport of O2 and CO2 in the soil. The model has four kinds of carbon pools including SOC, DOC, microbial biomass (MIC), and extracellular enzyme (ENZ). However, the model coupled with a land surface model, which accurately simulates soil moisture and temperature, failed to simulate the Birch effect observed at a natural savannah ecosystem site in the southwest US monsoon region. We further divided the DOC and ENZ pools into two sub-pools, one for a wet zone and the other for a dry zone, respectively. We assume that in the dry zone, DOC can be produced through enzyme catalysis, although at a lower rate due to enzyme immobilization, and only in the wet zone can microbes take up DOC. Thus, the modeled DOC accumulates during dry periods and is quickly transitioned into DOC in the wet zone (proportional to saturation) in response to pulsed wetting during a storm, and becomes available for microbial use. In such a way, the model successfully simulates the Birch effect with the Nash-Sutcliffe model efficiency being ~ 0.75 (correlation coefficient ~ 0.88) at a half-hourly time step. We will also present the effect of gas transport on the Birch effect

  4. Genotypic variation in yellow autumn leaf colours explains aphid load in silver birch.

    Science.gov (United States)

    Sinkkonen, Aki; Somerkoski, Eeva; Paaso, Ulla; Holopainen, Jarmo K; Rousi, Matti; Mikola, Juha

    2012-07-01

    • It has been suggested that autumn-migrating insects drive the evolution of autumn leaf colours. However, evidence of genetic variation in autumn leaf colours in natural tree populations and the link between the genetic variation and herbivore abundances has been lacking. • Here, we measured the size of the whole aphid community and the development of green-yellow leaf colours in six replicate trees of 19 silver birch (Betula pendula) genotypes at the beginning, in the middle and at the end of autumn colouration. We also calculated the difference between green leaf and leaf litter nitrogen (N) and estimated the changes in phloem sap N loading. • Autumn leaf colouration had significant genetic variation. During the last survey, genotypes that expressed the strongest leaf reflectance 2-4 wk earlier had an abundance of egg-laying Euceraphis betulae females. Surprisingly, the aphid community size during the first surveys explained N loss by the litter of different birch genotypes. • Our results are the first evidence at the tree intrapopulation genotypic level that autumn-migrating pests have the potential to drive the evolution of autumn leaf colours. They also stress the importance of recognizing the role of late-season tree-insect interactions in the evolution of herbivory resistance. PMID:22548444

  5. Quantification of Model Uncertainty in Modeling Mechanisms of Soil Microbial Respiration Pulses to Simulate Birch Effect

    Science.gov (United States)

    Elshall, A. S.; Ye, M.; Niu, G. Y.; Barron-Gafford, G.

    2014-12-01

    A Bayesian framework is developed to quantify predictive uncertainty in environmental modeling caused by uncertainty in modeling scenarios, model structures, model parameters, and data. An example of using the framework to quantify model uncertainty is presented to simulate soil microbial respiration pulses in response to episodic rainfall pulses (the "Birch effect"). A total of five models are developed; they evolve from an existing four-carbon (C) pool model to models with additional C pools and recently developed models with explicit representations of soil moisture controls on C degradation and microbial uptake rates. Markov chain Monte Carlo (MCMC) methods with generalized likelihood function (not Gaussian) are used to estimate posterior parameter distributions of the models, and the posterior parameter samples are used to evaluate probabilities of the models. The models with explicit representations of soil moisture controls outperform the other models. The models with additional C pools for accumulation of degraded C in the dry zone of the soil pore space result in a higher probability of reproducing the observed Birch pulses. A cross-validation is conducted to explore predictive performance of model averaging and of individual models. The Bayesian framework is mathematically general and can be applied to a wide range of environmental problems.

  6. Biochemical and growth acclimation of birch to night temperatures: genotypic similarities and differences.

    Science.gov (United States)

    Mäenpää, M; Ossipov, V; Kontunen-Soppela, S; Keinänen, M; Rousi, M; Oksanen, E

    2013-01-01

    The responses of plants to environmental factors are connected to the time of day. In this study, silver birch (Betula pendula) was grown in growth chambers at five different night temperatures (6-22 °C), using gradual changes during the evening and morning hours. Despite the increased night respiration and unaffected daytime net photosynthesis (per square metre), the carbon uptake (biomass) of birch did not decrease, probably due to enhanced biochemical processes on warmer nights and the advantage of higher temperatures during the evening and morning hours. The plant stem height, internode length, stem dry weight (DW), stem mass fraction and specific leaf area increased with warmer night temperatures. Changes in growth and metabolite concentrations were partly nonlinear along the temperature gradient. Thus, the temperature effect depends on the temperature window considered. Genotypes had both common and genotype-specific biochemical responses to night temperatures. The common responses among genotypes were related to growth responses, whereas the unique responses may indicate genotype-specific differences in acclimation. The differences in genotypic growth and metabolite levels are valuable for assessing genotype qualities and understanding the connections between the metabolome and growth.

  7. Elevated CO2 changes the moderate shade tolerance of yellow birch seedlings

    Institute of Scientific and Technical Information of China (English)

    CHENG Song

    2007-01-01

    To demonstrate the existence of light thresholds in plant growth and to examine the effects of elevated CO2 on the shade tolerance of a tree species, an experiment consisting of a completely randomized design for a total of 96 yellow birch (Betula alleghaniensis Britton) seedlings was conducted with 3 light levels (2.9%, 7.7%, 26.1% of full sunlight) × 2 CO2 levels (350 and 700±10 ppm) with 4 replications in a phytotron. The study proved that thresholds exist and they vary in different plant organs. In ambient CO2, the thresholds were 13.3%, 18.7%, 15.0%, 15.2%, and 15.6% of full sunlight for stem, leaf, root, total plant biomass, and the averaged value, respectively. In 700 ppm CO2, the corresponding thresholds were 16.7%, 21.3%, 18.1%, 21.7% and 19.5% for stem, leaf, root, total plant biomass, and the averaged value, respectively. The lowest threshold in the stem is an indicator of the minimal light intensity for regular growth for seedlings of this species. Below this threshold, light-stressful growth occurs. The result of a paired t-test indicated that the thresholds in elevated CO2 were significantly higher than in ambient CO2. This suggests that yellow birch will lose its moderate shade tolerance, evolutionally becoming a shade-intolerant species, and that it may become more difficult for it to naturally regenerate in the future.

  8. Fungal Assemblages in Different Habitats in an Erman’s Birch Forest

    Science.gov (United States)

    Yang, Teng; Sun, Huaibo; Shen, Congcong; Chu, Haiyan

    2016-01-01

    Recent meta-analyses of fungal diversity using deeply sequenced marker genes suggest that most fungal taxa are locally distributed. However, little is known about the extent of overlap and niche partitions in total fungal communities or functional guilds within distinct habitats on a local forest scale. Here, we compared fungal communities in endosphere (leaf interior), phyllosphere (leaf interior and associated surface area) and soil samples from an Erman’s birch forest in Changbai Mountain, China. Community structures were significantly differentiated in terms of habitat, with soil having the highest fungal richness and phylogenetic diversity. Endophytic and phyllosphere fungi of Betula ermanii were more phylogenetically clustered compared with the corresponding soil fungi, indicating the ability of that host plants to filter and select their fungal partners. Furthermore, the majority of soil fungal taxa were soil specialists, while the dominant endosphere and phyllosphere taxa were aboveground generalists, with soil and plant foliage only sharing birch forest were strictly niche specialized and constrained by weak migration among habitats. The findings suggest that phylogenetic relatedness and functional guilds’ assignment can effectively interpret the certain ecological processes. PMID:27625646

  9. Pentacyclic triterpenes in birch bark extract inhibit early step of herpes simplex virus type 1 replication.

    Science.gov (United States)

    Heidary Navid, M; Laszczyk-Lauer, M N; Reichling, J; Schnitzler, P

    2014-09-25

    Antiviral agents frequently applied for treatment of herpesvirus infections include acyclovir and its derivatives. The antiviral effect of a triterpene extract of birch bark and its major pentacyclic triterpenes, i.e. betulin, lupeol and betulinic acid against acyclovir-sensitive and acyclovir-resistant HSV type 1 strains was examined. The cytotoxic effect of a phytochemically defined birch bark triterpene extract (TE) as well as different pentacyclic triterpenes was analyzed in cell culture, and revealed a moderate cytotoxicity on RC-37 cells. TE, betulin, lupeol and betulinic acid exhibited high levels of antiviral activity against HSV-1 in viral suspension tests with IC50 values ranging between 0.2 and 0.5 μg/ml. Infectivity of acyclovir-sensitive and clinical isolates of acyclovir-resistant HSV-1 strains was significantly reduced by all tested compounds and a direct concentration- and time-dependent antiherpetic activity could be demonstrated. In order to determine the mode of antiviral action, TE and the compounds were added at different times during the viral infection cycle. Addition of these drugs to uninfected cells prior to infection or to herpesvirus-infected cells during intracellular replication had low effect on virus multiplication. Minor virucidal activity of triterpenes was observed, however both TE and tested compounds exhibited high anti-herpetic activity when viruses were pretreated with these drugs prior to infection. Pentacyclic triterpenes inhibit acyclovir-sensitive and acyclovir-resistant clinical isolates of HSV-1 in the early phase of infection.

  10. Moth outbreaks alter root-associated fungal communities in subarctic mountain birch forests.

    Science.gov (United States)

    Saravesi, Karita; Aikio, Sami; Wäli, Piippa R; Ruotsalainen, Anna Liisa; Kaukonen, Maarit; Huusko, Karoliina; Suokas, Marko; Brown, Shawn P; Jumpponen, Ari; Tuomi, Juha; Markkola, Annamari

    2015-05-01

    Climate change has important implications on the abundance and range of insect pests in forest ecosystems. We studied responses of root-associated fungal communities to defoliation of mountain birch hosts by a massive geometrid moth outbreak through 454 pyrosequencing of tagged amplicons of the ITS2 rDNA region. We compared fungal diversity and community composition at three levels of moth defoliation (intact control, full defoliation in one season, full defoliation in two or more seasons), replicated in three localities. Defoliation caused dramatic shifts in functional and taxonomic community composition of root-associated fungi. Differentially defoliated mountain birch roots harbored distinct fungal communities, which correlated with increasing soil nutrients and decreasing amount of host trees with green foliar mass. Ectomycorrhizal fungi (EMF) abundance and richness declined by 70-80 % with increasing defoliation intensity, while saprotrophic and endophytic fungi seemed to benefit from defoliation. Moth herbivory also reduced dominance of Basidiomycota in the roots due to loss of basidiomycete EMF and increases in functionally unknown Ascomycota. Our results demonstrate the top-down control of belowground fungal communities by aboveground herbivory and suggest a marked reduction in the carbon flow from plants to soil fungi following defoliation. These results are among the first to provide evidence on cascading effects of natural herbivory on tree root-associated fungi at an ecosystem scale. PMID:25687127

  11. CO2 and winter temperature effects on Norway spruce and downy birch : a comparative study

    International Nuclear Information System (INIS)

    A study was conducted to examine the effects of increased winter temperatures and higher carbon dioxide (CO2) levels on the growth of downy birch and Norway spruce, both important tree species in the northern forests of Fennoscandia. In the winter of 1992, three-year old seedlings from 3 different latitudinal populations were kept in greenhouses at winter ambient temperatures, and at winter temperatures raised by 4 degrees C. In the spring, the plants were moved to open chambers pre-set at 350 and 650 μmol/mol CO2. The following year, the experiment was repeated with one-year old seedlings. It was shown that at elevated CO2 levels, the shoot elongation rates and biomass was increased. There was a positive influence of winter temperature on shoot and biomass growth in the southern birch population from Norway but a negative effect on plants from Icelandic populations. High winters for spruce ecotypes appeared to reduce shoot growth for the following season. The reduced growth and premature loss was due to a temporary negative carbon balance in needles during unusually warm winters. 34 refs., 5 tabs., 5 figs

  12. Moth outbreaks alter root-associated fungal communities in subarctic mountain birch forests.

    Science.gov (United States)

    Saravesi, Karita; Aikio, Sami; Wäli, Piippa R; Ruotsalainen, Anna Liisa; Kaukonen, Maarit; Huusko, Karoliina; Suokas, Marko; Brown, Shawn P; Jumpponen, Ari; Tuomi, Juha; Markkola, Annamari

    2015-05-01

    Climate change has important implications on the abundance and range of insect pests in forest ecosystems. We studied responses of root-associated fungal communities to defoliation of mountain birch hosts by a massive geometrid moth outbreak through 454 pyrosequencing of tagged amplicons of the ITS2 rDNA region. We compared fungal diversity and community composition at three levels of moth defoliation (intact control, full defoliation in one season, full defoliation in two or more seasons), replicated in three localities. Defoliation caused dramatic shifts in functional and taxonomic community composition of root-associated fungi. Differentially defoliated mountain birch roots harbored distinct fungal communities, which correlated with increasing soil nutrients and decreasing amount of host trees with green foliar mass. Ectomycorrhizal fungi (EMF) abundance and richness declined by 70-80 % with increasing defoliation intensity, while saprotrophic and endophytic fungi seemed to benefit from defoliation. Moth herbivory also reduced dominance of Basidiomycota in the roots due to loss of basidiomycete EMF and increases in functionally unknown Ascomycota. Our results demonstrate the top-down control of belowground fungal communities by aboveground herbivory and suggest a marked reduction in the carbon flow from plants to soil fungi following defoliation. These results are among the first to provide evidence on cascading effects of natural herbivory on tree root-associated fungi at an ecosystem scale.

  13. Fire drives transcontinental variation in tree birch defense against browsing by snowshoe hares.

    Science.gov (United States)

    Bryant, John P; Clausen, Thomas P; Swihart, Robert K; Landhäusser, Simon M; Stevens, Michael T; Hawkins, Christopher D B; Carrière, Suzanne; Kirilenko, Andrei P; Veitch, Alasdair M; Popko, Richard A; Cleland, David T; Williams, Joseph H; Jakubas, Walter J; Carlson, Michael R; Bodony, Karin Lehmkuhl; Cebrian, Merben; Paragi, Thomas F; Picone, Peter M; Moore, Jeffrey E; Packee, Edmond C; Malone, Thomas

    2009-07-01

    Fire has been the dominant disturbance in boreal America since the Pleistocene, resulting in a spatial mosaic in which the most fire occurs in the continental northwest. Spatial variation in snowshoe hare (Lepus americanus) density reflects the fire mosaic. Because fire initiates secondary forest succession, a fire mosaic creates variation in the abundance of early successional plants that snowshoe hares eat in winter, leading to geographic variation in hare density. We hypothesize that fire is the template for a geographic mosaic of natural selection: where fire is greatest and hares are most abundant, hare browsing has most strongly selected juvenile-phase woody plants for defense. We tested the hypothesis at multiple spatial scales using Alaska birch (Betula neoalaskana) and white birch (Betula papyrifera). We also examined five alternative hypotheses for geographic variation in antibrowsing defense. The fire-hare-defense hypothesis was supported at transcontinental, regional, and local scales; alternative hypotheses were rejected. Our results link transcontinental variation in species interactions to an abiotic environmental driver, fire. Intakes of defense toxins by Alaskan hares exceed those by Wisconsin hares, suggesting that the proposed selection mosaic may coincide with a geographic mosaic of coevolution. PMID:19422319

  14. An investigation of the possible immunological relationship between allergen extracts from birch pollen, hazelnut, potato and apple

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Løwenstein, H

    1978-01-01

    In a retrospective study on selected group of patients, the coincidence of birch pollen allergy and a clinically relevant positive prick test reaction to apples and potatoes was confirmed. Immunochemical comparison using the crossed line immunoelectrophoresis technique (CLIE) confirmed partial id...

  15. Purification and characterization of natural Bet v 1 from birch pollen and related allergens from carrot and celery

    NARCIS (Netherlands)

    Bollen, M.A.; Garcia, A.; Cordewener, J.H.G.; Wichers, H.J.; Helsper, J.P.F.G.; Savelkoul, H.F.J.; Boekel, van M.A.J.S.

    2007-01-01

    Birch pollen allergy is predominantly caused by the major allergen Bet v 1 and can lead to crossreactions with homologous proteins in food. Two major cross-reactive food allergens are Dau c 1 from carrot and Api g 1 from celery, which have never been purified from their natural source. Here, we desc

  16. Academic Success for Students of Color . . . At What Cost? The Importance of School Context at Birch High School

    Science.gov (United States)

    Chambers, Terah T. Venzant; Tabron, Lolita A.

    2013-01-01

    Kiara, an African American rising freshman, has aspirations to become a medical doctor. She enrolls at Birch High School because of the reputation of the principal, Mr. Brown, whose vision for academic excellence permeates every corner of the school. Kiara graduates from high school with top honors, but realizes her success may have come at a…

  17. Woody Biomass and Carbon Stocks of Natural vs. Restored Mountain Birch (Betula pubescens, Ehrh.) Woodlands in South Iceland

    Science.gov (United States)

    Hunziker, Matthias; Sigurdsson, Bjarni D.; Halldorsson, Gudmundur; Kuhn, Nikolaus J.

    2010-05-01

    Following a period of land degradation lasting more than one thousand years, Iceland has been undertaken ambitious restoration and afforestation efforts for one century now. Afforestation has also been a central venture of the Icelandic government in order to meet the commitments assigned by the Kyoto Protocol because vegetation represents an important carbon sink. Yet, currently little is known on how much carbon is sequestrated effectively in afforested Icelandic woody ecosystems. In order to fill this knowledge gap the 'KolBjörk' (CarbBirch), a three year (2008-2011) Icelandic ecosystem research project, was launched. In this project the development of key ecosystem factors are studied in a chronosequence study of restored birch woodlands, ranging from 0-60 years in age. These factors are: a) forest growth, b) plant communities, c) soil biota, d) soil chemistry and physics and e) carbon stocks and fluxes. Restored woodlands are compared with: a) eroded land, representing the status of the area before restoration and b) original birch woodlands. The aim of present study which is part of 'KolBjörk' was to estimate the above-and belowground woody biomass and carbon stocks of old native birch (Betula pubescens) vs. restored birch woodlands in South Iceland. In summer 2009 31 trees (0.1-5.5m height) were measured and excavated and tree inventories (n=519) were established. The excavated trees formed the dataset to establish allometric biomass functions for young, afforested Icelandic mountain birch. The functions were statistically fitted using numerical nonlinear regression using Matlab. Subsequently, forest biomass and carbon stock of the four different old sites were estimated by the newly developed allometric relationships. The age of the four sites is 10, 15, 60 and 80 years, respectively, while the 80-yr old stand represents a natural grown forest, the others are replanted. The total C-stock in the 10-yr old birch stand was 2.0 Mg/ha, in the 15-yr old 11.0 Mg

  18. Phenolic compounds and expression of 4CL genes in silver birch clones and Pt4CL1a lines.

    Science.gov (United States)

    Sutela, Suvi; Hahl, Terhi; Tiimonen, Heidi; Aronen, Tuija; Ylioja, Tiina; Laakso, Tapio; Saranpää, Pekka; Chiang, Vincent; Julkunen-Tiitto, Riitta; Häggman, Hely

    2014-01-01

    A small multigene family encodes 4-coumarate:CoA ligases (4CLs) catalyzing the CoA ligation of hydroxycinnamic acids, a branch point step directing metabolites to a flavonoid or monolignol pathway. In the present study, we examined the effect of antisense Populus tremuloides 4CL (Pt4CL1) to the lignin and soluble phenolic compound composition of silver birch (Betula pendula) Pt4CL1a lines in comparison with non-transgenic silver birch clones. The endogenous expression of silver birch 4CL genes was recorded in the stems and leaves and also in leaves that were mechanically injured. In one of the transgenic Pt4CL1a lines, the ratio of syringyl (S) and guaiacyl (G) lignin units was increased. Moreover, the transcript levels of putative silver birch 4CL gene (Bp4CL1) were reduced and contents of cinnamic acid derivatives altered. In the other two Pt4CL1a lines changes were detected in the level of individual phenolic compounds. However, considerable variation was found in the transcript levels of silver birch 4CLs as well as in the concentration of phenolic compounds among the transgenic lines and non-transgenic clones. Wounding induced the expression of Bp4CL1 and Bp4CL2 in leaves in all clones and transgenic lines, whereas the transcript levels of Bp4CL3 and Bp4CL4 remained unchanged. Moreover, minor changes were detected in the concentrations of phenolic compounds caused by wounding. As an overall trend the wounding decreased the flavonoid content in silver birches and increased the content of soluble condensed tannins. The results indicate that by reducing the Bp4CL1 transcript levels lignin composition could be modified. However, the alterations found among the Pt4CL1a lines and the non-transgenic clones were within the natural variation of silver birches, as shown in the present study by the clonal differences in the transcripts levels of 4CL genes, soluble phenolic compounds and condensed tannins.

  19. Phenolic compounds and expression of 4CL genes in silver birch clones and Pt4CL1a lines.

    Directory of Open Access Journals (Sweden)

    Suvi Sutela

    Full Text Available A small multigene family encodes 4-coumarate:CoA ligases (4CLs catalyzing the CoA ligation of hydroxycinnamic acids, a branch point step directing metabolites to a flavonoid or monolignol pathway. In the present study, we examined the effect of antisense Populus tremuloides 4CL (Pt4CL1 to the lignin and soluble phenolic compound composition of silver birch (Betula pendula Pt4CL1a lines in comparison with non-transgenic silver birch clones. The endogenous expression of silver birch 4CL genes was recorded in the stems and leaves and also in leaves that were mechanically injured. In one of the transgenic Pt4CL1a lines, the ratio of syringyl (S and guaiacyl (G lignin units was increased. Moreover, the transcript levels of putative silver birch 4CL gene (Bp4CL1 were reduced and contents of cinnamic acid derivatives altered. In the other two Pt4CL1a lines changes were detected in the level of individual phenolic compounds. However, considerable variation was found in the transcript levels of silver birch 4CLs as well as in the concentration of phenolic compounds among the transgenic lines and non-transgenic clones. Wounding induced the expression of Bp4CL1 and Bp4CL2 in leaves in all clones and transgenic lines, whereas the transcript levels of Bp4CL3 and Bp4CL4 remained unchanged. Moreover, minor changes were detected in the concentrations of phenolic compounds caused by wounding. As an overall trend the wounding decreased the flavonoid content in silver birches and increased the content of soluble condensed tannins. The results indicate that by reducing the Bp4CL1 transcript levels lignin composition could be modified. However, the alterations found among the Pt4CL1a lines and the non-transgenic clones were within the natural variation of silver birches, as shown in the present study by the clonal differences in the transcripts levels of 4CL genes, soluble phenolic compounds and condensed tannins.

  20. Is the Growth of Birch at the UPPER Timberline in the Himalayas Limited By Moisture or By Temperature?

    Science.gov (United States)

    Liang, E.; Dawadi, B.; Pederson, N.; Eckstein, D.

    2014-12-01

    Birch (Betula) trees and forests are found across much of the temperate and boreal zones of the Northern Hemisphere. Yet, despite being an ecologically-significant genus, it is much less-well studied compared to common genera like Pinus, Picea, Juniperus, Quercus, and Fagus. In the Himalayas, Himalayan birch (Betula utilis) is a widespread, important broadleaf timberline species that survives in mountain rain shadows via access to water from snowmelt. Because precipitation in the Nepalese Himalayas decreases with increasing elevation, we hypothesized that the growth of birch at the upper timberlines between 3,900 and 4,150 m a.s.l. is primarily limited by moisture availability rather than by low temperature. To verify this assumption, a total of 292 increment cores were extracted from 211 birch trees at nine timberline sites. The synchronous occurrence of narrow rings and high inter-series correlations within and among sites evidenced a reliable cross-dating and a common climatic signal in the tree-ring widths variations. From March-May, all nine tree-ring width site chronologies showed a strongly positive response to total precipitation and a less strongly negative response to temperature. During the instrumental meteorological record (after 1960), years with a high percentage of missing rings coincided with pre-monsoon drought events. Periods of below-average growth are in phase with well-known drought events all over monsoon Asia, showing additional evidence that Himalayan birch growth at the upper timberlines is persistently limited by moisture availability. Our study describes the rare case of a drought-induced altitudinal timberline that is composed by a broadleaf tree species.

  1. From a traditional medicinal plant to a rational drug: understanding the clinically proven wound healing efficacy of birch bark extract.

    Directory of Open Access Journals (Sweden)

    Sandra Ebeling

    Full Text Available BACKGROUND: Birch bark has a long lasting history as a traditional medicinal remedy to accelerate wound healing. Recently, the efficacy of birch bark preparations has also been proven clinically. As active principle pentacyclic triterpenes are generally accepted. Here, we report a comprehensive study on the underlying molecular mechanisms of the wound healing properties of a well-defined birch bark preparation named as TE (triterpene extract as well as the isolated single triterpenes in human primary keratinocytes and porcine ex-vivo wound healing models. METHODOLOGY/PRINCIPAL FINDINGS: We show positive wound healing effects of TE and betulin in scratch assay experiments with primary human keratinocytes and in a porcine ex-vivo wound healing model (WHM. Mechanistical studies elucidate that TE and betulin transiently upregulate pro-inflammatory cytokines, chemokines and cyclooxygenase-2 on gene and protein level. For COX-2 and IL-6 this increase of mRNA is due to an mRNA stabilizing effect of TE and betulin, a process in which p38 MAPK and HuR are involved. TE promotes keratinocyte migration, putatively by increasing the formation of actin filopodia, lamellipodia and stress fibers. Detailed analyses show that the TE components betulin, lupeol and erythrodiol exert this effect even in nanomolar concentrations. Targeting the actin cytoskeleton is dependent on the activation of Rho GTPases. CONCLUSION/SIGNIFICANCE: Our results provide insights to understand the molecular mechanism of the clinically proven wound healing effect of birch bark. TE and betulin address the inflammatory phase of wound healing by transient up-regulation of several pro-inflammatory mediators. Further, they enhance migration of keratinocytes, which is essential in the second phase of wound healing. Our results, together with the clinically proven efficacy, identify birch bark as the first medical plant with a high potential to improve wound healing, a field which urgently

  2. Analysis of three types of triterpenoids in tetraploid white birches (Betula platyphylla Suk.) and selection of plus trees

    Institute of Scientific and Technical Information of China (English)

    Sui Wang; Hui Zhao; Jing Jiang; Guifeng Liu; Chuanping Yang

    2015-01-01

    Betulin, oleanolic acid, and betulinic acid are naturally occurring pentacyclic triterpenoids that have significant medicinal value. Considerable amounts of these triterpenoids are available in the outer bark of white birch. In this study, we used ultrasound-assisted extraction (UAE) to extract triterpenoids from birch bark rapidly and with high efficiency. Using high performance liquid chro-matography (HPLC), three types of triterpenoids were separated and detected. We examined the differences among triterpenoids extracted from diploid versus tetra-ploid white birch. Then, we used factor analysis to screen out tetraploid white birches with comprehensively excel-lent performance. The results indicate that the optimum conditions for extraction include the use of ethanol as an extraction solvent, a solid-to-liquid ratio of 0.1 g/10 ml, ultrasonic power set at 100 W, a temperature of 60 ?C and an extraction time of 15 min. A reversed-phase C18 col-umn (4.6 mm 9 250 mm 9 5 lm) with a column tem-perature of 30 ?C and the mobile phase composed of A (acetonitrile) and B (0.1% aqueous phosphoric acid, v/v) at a flow rate of 0.5 ml/min were used, and the detection wavelength was 195 nm. No significant difference was observed between diploid and tetraploid white birch in terms of the content of three types of triterpenoids (at a confidence level of 0.05). As triterpenoid content, height, and DBH (diameter at breast height) are strongly interre-lated, we used factor analysis to evaluate all individuals, and we screened out six plus trees with excellent com-prehensive characters.

  3. Soil Chemical and Microbial Properties in a Mixed Stand of Spruce and Birch in the Ore Mountains (Germany—A Case Study

    Directory of Open Access Journals (Sweden)

    Karoline Schua

    2015-06-01

    Full Text Available A major argument for incorporating deciduous tree species in coniferous forest stands is their role in the amelioration and stabilisation of biogeochemical cycles. Current forest management strategies in central Europe aim to increase the area of mixed stands. In order to formulate statements about the ecological effects of mixtures, studies at the stand level are necessary. In a mixed stand of Norway spruce (Picea abies (L. Karst. and silver birch (Betula pendula Roth in the Ore Mountains (Saxony, Germany, the effects of these two tree species on chemical and microbial parameters in the topsoil were studied at one site in the form of a case study. Samples were taken from the O layer and A horizon in areas of the stand influenced by either birch, spruce or a mixture of birch and spruce. The microbial biomass, basal respiration, metabolic quotient, pH-value and the C and N contents and stocks were analysed in the horizons Of, Oh and A. Significantly higher contents of microbial N were observed in the Of and Oh horizons in the birch and in the spruce-birch strata than in the stratum containing only spruce. The same was found with respect to pH-values in the Of horizon and basal respiration in the Oh horizon. Compared to the spruce stratum, in the birch and spruce-birch strata, significantly lower values were found for the contents of organic C and total N in the A horizon. The findings of the case study indicated that single birch trees have significant effects on the chemical and microbial topsoil properties in spruce-dominated stands. Therefore, the admixture of birch in spruce stands may distinctly affect nutrient cycling and may also be relevant for soil carbon sequestration. Further studies of these functional aspects are recommended.

  4. Quantification of C uptake in subarctic birch forest after setback by an extreme insect outbreak

    DEFF Research Database (Denmark)

    Heliasz, Michal; Johansson, Torbjörn; Lindroth, Anders;

    2011-01-01

    ) forests in northern Scandinavia cyclically every 9–10 years and occasionally (50–150 years) extreme population densities can threaten ecosystem stability. Here we report impacts on C balance following a 2004 outbreak where a widespread area of Lake Torneträsk catchment was severely defoliated. We show......The carbon dynamics of northern natural ecosystems contribute significantly to the global carbon balance. Periodic disturbances to these dynamics include insect herbivory. Larvae of autumn and winter moths (Epirrita autumnata and Operophtera brumata) defoliate mountain birch (Betula pubescens...... that in the growing season of 2004 the forest was a much smaller net sink of C than in a reference year, most likely due to lower gross photosynthesis. Ecosystem respiration in 2004 was smaller and less sensitive to air temperature at nighttime relative to 2006. The difference in growing season uptake...

  5. Birch inner bark procyanidins can be resolved with enhanced sensitivity by hydrophilic interaction HPLC-MS.

    Science.gov (United States)

    Karonen, Maarit; Liimatainen, Jaana; Sinkkonen, Jari

    2011-11-01

    A complex mixture of procyanidin aglycones was isolated by Sephadex LH-20 column chromatography from the silver birch inner bark, which is a polyphenol-rich source of natural antioxidants. Procyanidins were studied by using hydrophilic interaction liquid chromatography combined with high-resolution ESI-TOF-MS. A good chromatographic separation was achieved and procyanidins eluted according to their increasing degree of polymerization. Individual procyanidins were detected from dimers up to the degree of polymerization of 22 by their negative-ion mass spectra. The results showed that hydrophilic interaction liquid chromatography can be successfully applied for the analysis of high-molecular-weight procyanidins with enhanced sensitivity in electrospray mass spectrometry. PMID:21998029

  6. Properties of plasticized composite films prepared from nanofibrillated cellulose and birch wood xylan

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Blomfeldt, Thomas O. J.; Hedenqvist, Mikael S.;

    2012-01-01

    was combined with nanofibrillated cellulose (NFC) and films were cast with and without glycerol, sorbitol or methoxypolyethylene glycol (MPEG) as plasticizers. Microscopy revealed some NFC agglomeration in the composite films as well as a layered nanocellulose structure. Equilibrium moisture content......Xylans, an important sub-class of hemicelluloses, represent a largely untapped resource for new renewable materials derived from biomass. As with other carbohydrates, nanocellulose reinforcement of xylans is interesting as a route to new bio-materials. With this in mind, birch wood xylan...... with increased NFC content in the xylan:NFC composition range from 50:50 to 80:20 and plasticizer addition generally provided less brittle films. The oxygen permeability of unplasticized xylan-NFC films fell into a range which was similar to that for previously measured pure NFC films and was statistically...

  7. 桦木板材的快速干燥%Rapid Drying of Birch Lumber

    Institute of Scientific and Technical Information of China (English)

    李增超; 邱增处; 杨庆; 雷亚芳

    2001-01-01

    采用阶段连续升温干燥基准,增加热湿处理工艺,用炉气间接加热木材干燥窑对不同厚度桦木锯材进行快速窑干工艺试验,实践证明不但干燥周期缩短30%,且提高了干燥质量,易于操作。%Rapid kiln-drying experiment on birch lumber of kiln in whichphased continuous heating drying schedule and the conditioning technology are adopted.It has been proved in practice that such kiln-drying technology can not only shorten the drying period by 30% but also improve drying quality as well as be operated easily.

  8. Soil Properties Control Glyphosate Sorption in Soils Amended with Birch Wood Biochar

    DEFF Research Database (Denmark)

    Kahawaththa Gamage, Inoka Damayanthi Kumari; Moldrup, Per; Paradelo, Marcos;

    2016-01-01

    to soils. Yet, at the Kalundborg soils, the application of biochar enhanced the sorption of glyphosate when tested after 7–19 months of soil–biochar interaction. The relative enhancement effect on glyphosate sorption diminished with increasing biochar application rate, presumably due to increased mineral......Abstract Despite a contemporary interest in biochar application to agricultural fields to improve soil quality and long-term carbon sequestration, a number of potential side effects of biochar incorporation in field soils remain poorly understood, e.g., in relation to interactions...... with agrochemicals such as pesticides. In a fieldbased study at two experimental sites in Denmark (sandy loam soils at Risoe and Kalundborg), we investigated the influence of birch wood biochar with respect to application rate, aging (7–19 months), and physico- chemical soil properties on the sorption coefficient...

  9. Breeding increases the efficacy of Chondrostereum purpureum in the sprout control of birch.

    Directory of Open Access Journals (Sweden)

    Leena Hamberg

    Full Text Available We tested whether the pairing of selected isolates could be used to increase the efficiency of a decay fungus Chondrostereum purpureum (Pers. Ex Fr. Pouzar to control hardwood sprouting in Finland. We paired C. purpureum strains efficient in sprout control or highly active in laccase production, and tested the efficacy of their progeny in spout control experiments. This procedure resulted in a strain with an efficacy superior to that of the parental strains. The mortality of birch (Betula pendula Roth. and B. pubescens Ehrh. 1 cm in stump diameter was 78%, 56% and 9% for the best progeny, the best parental strain and the control, respectively. Mortality was only slightly higher for B. pendula than for B. pubescens but no significant differences were found between the number or maximum height of stump sprouts. Our results showed that cross breeding of this decay fungus is a good alternative in attempts to produce efficient biocontrol agents against hardwood sprouting.

  10. Chemical and physical characterization of emissions from birch wood combustion in a wood stove

    Science.gov (United States)

    Hedberg, Emma; Kristensson, Adam; Ohlsson, Michael; Johansson, Christer; Johansson, Per-Åke; Swietlicki, Erik; Vesely, Vaclav; Wideqvist, Ulla; Westerholm, Roger

    The purpose of this study was to characterize the emissions of a large number of chemical compounds emitted from birch wood combustion in a wood stove. Birch wood is widely used as fuel in Swedish household appliances. The fuel load was held constant during six experiments. Particles dust, range 30-330 for the former and 0.8±0.15 for the latter. The source profile of common elements emitted from wood burning differed from that found on particles at a street-level site or in long-distance transported particles. The ratio toluene/benzene in this study was found to be in the range 0.2-0.7, which is much lower than the ratio 3.6±0.5 in traffic exhaust emissions. Formaldehyde and acetone were the most abundant compounds among the volatile ketones and aldehydes. The emission factor varied between 180-710 mg/kg wood for formaldehyde and 5-1300 mg/kg wood for acetone. Of the organic acids analyzed (3,4,5)-trimethoxy benzoic acid was the most abundant compound. Of the PAHs reported, fluorene, phenanthrene, anthracene, fluoranthene and pyrene contribute to more than 70% of the mass of PAH. Of the elements analyzed, K and Si were the most abundant elements, having emission factors of 27 and 9 mg/kg wood, respectively. Although fluoranthene has a toxic equivalence factor of 5% of benzo(a)pyrene (B(a)P), it can be seen that the toxic potency of fluoranthene in wood burning emissions is of the same size as B(a)P. This indicates that the relative carcinogenic potency contribution of fluoranthene in wood smoke would be about 40% of B(a)P.

  11. Volatile organic compounds emitted from silver birch of different provenances across a latitudinal gradient in Finland.

    Science.gov (United States)

    Maja, Mengistu M; Kasurinen, Anne; Holopainen, Toini; Kontunen-Soppela, Sari; Oksanen, Elina; Holopainen, Jarmo K

    2015-09-01

    Climate warming is having an impact on distribution, acclimation and defence capability of plants. We compared the emission rate and composition of volatile organic compounds (VOCs) from silver birch (Betula pendula (Roth)) provenances along a latitudinal gradient in a common garden experiment over the years 2012 and 2013. Micropropagated silver birch saplings from three provenances were acquired along a gradient of 7° latitude and planted at central (Joensuu 62°N) and northern (Kolari 67°N) sites. We collected VOCs emitted by shoots and assessed levels of herbivore damage of three genotypes of each provenance on three occasions at the central site and four occasions at the northern site. In 2012, trees of all provenances growing at the central site had higher total VOC emission rates than the same provenances growing at the northern site; in 2013 the reverse was true, thus indicating a variable effect of latitude. Trees of the southern provenance had lower VOC emission rates than trees of the central and northern provenances during both sampling years. However, northward or southward translocation itself had no significant effect on the total VOC emission rates, and no clear effect on insect herbivore damage. When VOC blend composition was studied, trees of all provenances usually emitted more green leaf volatiles at the northern site and more sesquiterpenes at the central site. The monoterpene composition of emissions from trees of the central provenance was distinct from that of the other provenances. In summary, provenance translocation did not have a clear effect in the short-term on VOC emissions and herbivory was not usually intense at the lower latitude. Our data did not support the hypothesis that trees growing at lower latitudes would experience more intense herbivory, and therefore allocate resources to chemical defence in the form of inducible VOC emissions. PMID:26093370

  12. Cyclically outbreaking geometrid moths in sub-arctic mountain birch forest: the organization and impacts of their interactions with animal communities

    OpenAIRE

    Vindstad, Ole Petter Laksforsmo

    2015-01-01

    In sub-arctic mountain birch forest in northern Fennoscandia, the 2 geometrid moth species Epirrita autumnata (autumnal moth) and Operophtera brumata (winter moth) show high-amplitude population cycles with regular 10-year periodicity. During some population peaks, moth populations attain outbreak densities and cause region-wide defoliation and mortality of mountain birch. The severity and duration of moth outbreaks presently appears to be increasing, owing to climate-driven range-expansions ...

  13. Short term effects of clear cutting on the regeneration of sub-arctic birch forest following severe outbreaks by geometrid moths

    OpenAIRE

    Klinghardt, Moritz

    2013-01-01

    Birch forests in northern Fennoscandia experience re-occurring mass outbreaks of pest insects often resulting in severe defoliation. Here I test whether systematic clear cutting can accelerate the forest regeneration after outbreaks with uncut control plots as comparison. Basal shoot abundance was used as a main indicator for recovery but comprehensive data sampling also included the abundance of birch saplings, herbivore presence and understorey vegetation. Treatment responses of basal shoot...

  14. Changes in expression of BetV1 allergen of silver birch pollen in urbanized area of Ukraine.

    Science.gov (United States)

    Žiarovská, Jana; Labajová, Mária; Ražná, Katarína; Bežo, Milan; Štefúnová, Veronika; Shevtsova, Tatiana; Garkava, Kateryna; Brindza, Ján

    2013-01-01

    The aim of the study was to determinate the level of expression of silver birch allergen Betv1 in pollen samples from different Ukraine areas by RT-qPCR SYBR Green assay. Protocol for quantifying the expression of Betv1 allergen was developed when testing of three housekeeping genes-cyclophylin, alpha-tubulin and transcription factor CBF1. Samples from urbanized area was analysed by real-time PCR when a sample from forest growth conditions was used as a calibrator. Real-time PCR based quantifying of Betv1 provides a useful method for rapid and sensitive analyses of this silver birch allergen. Our results show higher expression levels in samples from central parts of urbanized area as housing estates when compared to the samples from borders of the urbanized area.

  15. The major birch pollen allergen Bet v 1 induces different responses in dendritic cells of birch pollen allergic and healthy individuals.

    Directory of Open Access Journals (Sweden)

    Ursula Smole

    Full Text Available Dendritic cells play a fundamental role in shaping the immune response to allergens. The events that lead to allergic sensitization or tolerance induction during the interaction of the major birch pollen allergen Bet v 1 and dendritic cells are not very well studied. Here, we analyzed the uptake of Bet v 1 and the cross-reactive celery allergen Api g 1 by immature monocyte-derived dendritic cells (iMoDCs of allergic and normal donors. In addition, we characterized the allergen-triggered intracellular signaling and transcriptional events. Uptake kinetics, competitive binding, and internalization pathways of labeled allergens by iMoDCs were visualized by live-cell imaging. Surface-bound IgE was detected by immunofluorescence microscopy and flow cytometry. Allergen- and IgE-induced gene expression of early growth response genes and Th1 and Th2 related cytokines and chemokines were analyzed by real-time PCR. Phosporylation of signaling kinases was analyzed by Western blot. Internalization of Bet v 1 by iMoDCs of both donor groups, likely by receptor-mediated caveolar endocytosis, followed similar kinetics. Bet v 1 outcompeted Api g 1 in cell surface binding and uptake. MoDCs of allergic and healthy donors displayed surface-bound IgE and showed a pronounced upregulation of Th2 cytokine- and NFκB-dependent genes upon non-specific Fcε receptor cross-linking. In contrast to these IgE-mediated responses, Bet v 1-stimulation increased transcript levels of the Th2 cytokines IL-4 and IL-13 but not of NFκB-related genes in MoDCs of BP allergic donors. Cells of healthy donors were either unresponsive or showed elevated mRNA levels of Th1-promoting chemokines. Moreover, Bet v 1 was able to induce Erk1/2 and p38 MAPK activation in BP allergics but only a slight p38 activation in normal donors. In conclusion, our data indicate that Bet v 1 favors the activation of a Th2 program only in DCs of BP allergic individuals.

  16. Pimecrolimus Is a Potent Inhibitor of Allergic Reactions to Hymenopteran Venom Extracts and Birch Pollen Allergen In Vitro

    OpenAIRE

    Petr Heneberg; Kamila Riegerová; Petr Kučera

    2015-01-01

    Pimecrolimus (Elidel, SDZ ASM 981) is an anti-inflammatory and immunomodulatory 33-epichloro-derivative of macrolactam ascomycin, with low potential for affecting systemic immune responses compared with other calcineurin inhibitors, cyclosporin A and tacrolimus. Despite numerous studies focused on the mechanism of pimecrolimus action on mast cells, only the single report has addressed pimecrolimus effects on other typical FcεRI-expressing cells, the basophils. Patients allergic to birch polle...

  17. Plant and insect diversity along an experimental gradient of larch-birch mixtures in Chinese boreal forests

    OpenAIRE

    Li, Jing; Shi, Juan; Luo, Youqing; HELIÖVAARA, Kari

    2012-01-01

    Maintaining and increasing biodiversity level especially in pure plantations is one important way to improve the resistance of forests to pests in Chinese boreal forests. The present study tested the hypothesis that the increased degree of tree species mixture (quantified by the stem proportion of Betula platyphylla Suk. and Larix gmelinii (Rupr.) Rupr.) can affect the species richness and diversity of understory and insects. Twenty-one plots, ranging from pure larch stand to pure birch stand...

  18. DYNAMICS AND DISTINCTIONS IN CONCENTRATION OF THE BASIC PHOTOSYNTHETIC PIGMENTS OF LEAVES OF THE BIRCH GROWING IN IMPURE CONDITIONS

    Directory of Open Access Journals (Sweden)

    Михаил Эдуардович Баландайкин

    2014-09-01

    Full Text Available The complex of features of influence of external factors on frame of the basic photosynthetic pigments of a sheet plate of a birch is discussed. Besides, specificity of influence of the infectious pathological stress-factor – xylotroph basidial macromycet (facultative saprotroph a tinder fungus bevelled – on the content of a chlorophyll of phylum a, b, their sums, lipochromes, an interrelation of pigments in sheet plates of trees Betula pendula Roth. is shown.

  19. Detection and analysis of unusual features in the structural model and structure-factor data of a birch pollen allergen

    OpenAIRE

    Rupp, Bernhard

    2012-01-01

    Physically improbable features in the model of the birch pollen structure Bet v 1d (PDB entry 3k78) are faithfully reproduced in electron density generated with the deposited structure factors, but these structure factors themselves exhibit properties that are characteristic of data calculated from a simple model and are inconsistent with the data and error model obtained through experimental measurements. The refinement of the 3k78 model against these structure factors leads to an isomorphou...

  20. New datasets for quantifying snow-vegetation-atmosphere interactions in boreal birch and conifer forests

    Science.gov (United States)

    Reid, T. D.; Essery, R.; Rutter, N.; Huntley, B.; Baxter, R.; Holden, R.; King, M.; Hancock, S.; Carle, J.

    2012-12-01

    Boreal forests exert a strong influence on weather and climate by modifying the surface energy and radiation balance. However, global climate and numerical weather prediction models use forest parameter values from simple look-up tables or maps that are derived from limited satellite data, on large grid scales. In reality, Arctic landscapes are inherently heterogeneous, with highly variable land cover types and structures on a variety of spatial scales. There is value in collecting detailed field data for different areas of vegetation cover, to assess the accuracy of large-scale assumptions. To address these issues, a consortium of researchers funded by the UK's Natural Environment Research Council have collected extensive data on radiation, meteorology, snow cover and canopy structure at two contrasting Arctic forest sites. The chosen study sites were an area of boreal birch forest near Abisko, Sweden in March/April 2011 and mixed conifer forest at Sodankylä, Finland in March/April 2012. At both sites, arrays comprising ten shortwave pyranometers and four longwave pyrgeometers were deployed for periods of up to 50 days, under forest plots of varying canopy structures and densities. In addition, downwelling longwave irradiance and global and diffuse shortwave irradiances were recorded at nearby open sites representing the top-of-canopy conditions. Meteorological data were recorded at all sub-canopy and open sites using automatic weather stations. Over the same periods, tree skin temperatures were measured on selected trees using contact thermocouples, infrared thermocouples and thermal imagery. Canopy structure was accurately quantified through manual surveys, extensive hemispherical photography and terrestrial laser scans of every study plot. Sub-canopy snow depth and snow water equivalent were measured on fine-scale grids at each study plot. Regular site maintenance ensured a high quality dataset covering the important Arctic spring period. The data have several

  1. Features of secondary birch young stands in low mountain Pokuttya (Ukrainian Carpathian mts.

    Directory of Open Access Journals (Sweden)

    S. Y. Milevskaya

    2015-06-01

    Full Text Available Forest landscapes of the region during the last 3–5 centuries undergone the profound anthropogenic transformation. Secondary young stands occupy 25% of the total forest area. The problem of derivatives is particularly relevant for the modern forest typology in the Carpathian region. It requires the reflection in its dynamic trends shaping the stands, especially mixed young stands. The aim of our study consisted in getting the knowledge of the structural features of the secondary phytocoenosis of birch young stands in this area.The object of the study was age class I saplings growing in the mountainous part of Pokuttya, particularly in the basin of the Lutshka River. The conceptual basis of our study is the modern dynamic vision that every forest type is a consecutive series of forest plant communities within each type of homogeneous growing conditions. We apply methods of ecological-floristic research of the Brown-Blanke school in the interpretation of the Polish school phytosociology. However we also take into account both syntaxonomy generalizations of the Ukrainian scientists. The actual material comprises the original geobotanical studies with fixation of the vast majority of species in plant communities. Mainly the species having diagnostic value to separate syntaxons were taken into account in the analytical processing. Young forest stands (with the height of 8–12 m and crown cover of 70% together form the trees Betula pendula and B. pubescens. Fairly numerous admixture is formed by trees Alnus incana; besides, there are Fagus sylvatica, Populus tremula, Quercus robur, Padus avium. For dominants, they can be called “grey-alder birch blackberry sedge bracken fern” – Betula pendula+Alnus incana–Rubus caesius–Carex brizoides+Pteridium aquilinum. It is rich in floristic composition of the plant communities. They contain at least 12 species of trees, 3 species of shrubs, 4 species of bushes and 89 species of herbs. Diagnostic

  2. 白桦木材生物变色的防治方法%Control of White Birch Biological Discoloration

    Institute of Scientific and Technical Information of China (English)

    张斌; 陈广胜; 郭明辉; 黄占华; 朱晓冬

    2014-01-01

    Six kinds of chemicals were chosen for bacteriostatic ring experiment , the agent of birch wood discoloration prevention were screened .Among six kinds of chemicals , four were selected for biological control experimental of white birch wood discoloration .The chemical reagent and appropriate concentration could inhibit the bacteria growth , and reduce the extent of discoloration of birch wood .Because different chemicals have different effects on the infection effect of bacteria , the chemical compound can improve the ability of inhibition of wood stain fungi in preventing wood biological discoloration .%采用抑菌圈试验,分析6种化学药剂对白桦木材侵染菌的抑菌效果;并选择其中4种药剂对白桦木材生物变色防治进行探索性试验。结果表明,适宜质量分数的化学试剂Benomyl 和BAC能够抑制白桦木材浸染菌的生长。由于不同的化学药剂对不同侵染菌种类的抑制效果不同,在白桦木材生物变色的防治过程中进行化学药剂的复配将会有助于提高对变色菌的抑制能力。

  3. Birch pulp xylan works as a food hydrocolloid in acid milk gels and is fermented slowly in vitro.

    Science.gov (United States)

    Rosa-Sibakov, Natalia; Hakala, Terhi K; Sözer, Nesli; Nordlund, Emilia; Poutanen, Kaisa; Aura, Anna-Marja

    2016-12-10

    The objective was to evaluate the potential of birch xylan as a food hydrocolloid and dietary fibre. High-molecular weight xylan was isolated from birch kraft pulp by alkaline extraction, and enzymatically hydrolysed. Fermentability of xylans was evaluated using an in vitro colon model and performance as a hydrocolloid was studied in low-fat acid milk gels (1.5% and 3% w/w). Texture of the gels and water holding capacity of xylans were compared with inulin, fructooligosaccharide and xylooligosaccharide. Xylans showed slower fermentation rate by faecal microbiota than the references. Xylan-enriched acid milk gels (3% w/w) had improved water holding capacity (over 2-fold) and showed lower spontaneous syneresis, firmness and elasticity when compared to control (no hydrocolloids) or to references. In conclusion, birch xylan improved texture of low-fat acid milk gel applications, and the slow in vitro fermentation rate predicts lower incidence of intestinal discomfort in comparison to the commercial references. PMID:27577922

  4. Impact of ectohumus application in birch and pine nurseries on the presence of soil mites (Acari, Oribatida in particular

    Directory of Open Access Journals (Sweden)

    Klimek Andrzej

    2016-03-01

    Full Text Available Intensively used forest nurseries are characterised by degradation processes that lead to a drop in the quality of seedlings. The main reason of this problem is a decrease in biological soil diversity. Therefore, an attempt of nursery soil enrichment by introducing ectohumus – as compost and fresh litter – from the pine forest was carried out. The research was carried out in 2009–2011 in the Bielawy forest nursery near the city of Toruń, Poland. The objective of the study was to determine the impact of organic fertilisation (compost made up of forest humus and mulching using fresh ectohumus on the density and community composition of Acari mites and on species composition of oribatid mites (Oribatida in the nurseries of silver birch and Scots pine. Mites, especially oribatid mites, were treated as bioindicators of soil biological activity. Research has shown that mulching using fresh ectohumus caused a multiple increase in the density of mites, especially in saprophagous mites Oribatida. Oribatid mites were clearly more numerous in birch cultivation than in that of pine. Overall, 27 species of oribatid mites were found. Mulching resulted in a significant growth in species diversity in both cultivations. The most numerous oribatid mite in the area under the study was Oribatula tibialis. This species was present in all plots and showed clear preference for birch cultivation. Tectocepheus velatus and Oppiella nova, common and known to be present in a variety of environments, were slightly less numerous.

  5. Analysis of Individual Tree Competition Effect on Diameter Growth of Silver Birch in Estonia

    Directory of Open Access Journals (Sweden)

    Kobra Maleki

    2015-08-01

    Full Text Available Aim of study: The present study evaluates a set of competition indices including spatially explicit indices combined with different competitor selection approaches and non-spatially explicit competition indices. The aim was to quantify and describe the neighbouring effects on the tree diameter growth of silver birch trees. Area of study: Region throughout Estonia. Material and methods: Data from the Estonian Network of Forest Research Plots was used. After quantifying the selected indices, the best non-spatial indices and spatial indices (combined with neighbour selection methods were separately devised into a growth model as a predictor variable to assess the ability of the diameter growth model before and after adding competition measures. To test the species-specific effect on the competition level, the superior indices were recalculated using Ellenberg’s light indicators and incorporated into the diameter growth model. Main results: Statistical analyses showed that the diameter growth is a function of neighbourhood interactions and spatial indices were better growth predictors than non-spatial indices. In addition, the best selections of competitive neighbours were acquired based on the influence zone and the competition elimination angle concepts, and using Ellenberg’s light values had no significant improvement in quantifying the competition effects. Research highlights: Although the best ranking spatial competition measures were superior to the best non-spatial indices, the differences were negligible.

  6. Carbohydrate concentrations and freezing stress resistance of silver birch buds grown under elevated temperature and ozone.

    Science.gov (United States)

    Riikonen, Johanna; Kontunen-Soppela, Sari; Vapaavuori, Elina; Tervahauta, Arja; Tuomainen, Marjo; Oksanen, Elina

    2013-03-01

    The effects of slightly elevated temperature (+0.8 °C), ozone (O3) concentration (1.3 × ambient O3 concentration) and their combination on over-wintering buds of Betula pendula Roth were studied after two growing seasons of exposure in the field. Carbohydrate concentrations, freezing stress resistance (FSR), bud dry weight to fresh weight ratio, and transcript levels of cytochrome oxidase (COX), alternative oxidase (AOX) and dehydrin (LTI36) genes were studied in two clones (clones 12 and 25) in December. Elevated temperature increased the bud dry weight to fresh weight ratio and the ratio of raffinose family oligosaccharides to sucrose and the transcript levels of the dehydrin (LTI36) gene (in clone 12 only), but did not alter the FSR of the buds. Genotype-specific alterations in carbohydrate metabolism were found in the buds grown under elevated O3. The treatments did not significantly affect the transcript level of the COX or AOX genes. No clear pattern of an interactive effect between elevated temperature and O3 concentration was found. According to these data, the increase in autumnal temperatures and slightly increasing O3 concentrations do not increase the risk for freeze-induced damage in winter in silver birch buds, although some alterations in bud physiology occur.

  7. EFFECT OF XYLANASE TREATMENT ON DEWATERING PROPERTIES OF BIRCH KRAFT PULP

    Directory of Open Access Journals (Sweden)

    Minna Marianne Blomstedt

    2010-04-01

    Full Text Available In this study it was shown that the enzymatic removal of xylan from ECF-bleached birch kraft pulp enhances the water removal from the pulp, especially in the late stages of pulp drying. The effect of xylanase treatments on dewatering was clarified by using a moving belt former (MBF, a press simulator (MTS, and an IR-drying equipment, to simulate and to measure dewatering properties on wire, press and drying sections of a paper machine. The xylanase treatment slightly increased the pulp freeness indicating improved pulp drainage properties. At the moving belt former, however, no significant changes that would indicate enhanced dewatering in forming were observed. The xylanase treatments slightly enhanced the dewatering in wet pressing and furthermore, at the thermal drying the xylanase treatment had a positive effect on the dry solid content (DSC development, and time to reach the 95% dry solids content was reduced by up to 15%. This was also confirmed by the decrease in the fiber saturation point (FSP values and the amount of bulk water. Our results indicate that the xylanase treatment affected the water-binding xylan in the fiber cell wall, yielding enhanced dewatering properties, without deteriorating the pulp and paper properties.

  8. Low vapour pressure deficit affects nitrogen nutrition and foliar metabolites in silver birch.

    Science.gov (United States)

    Lihavainen, Jenna; Ahonen, Viivi; Keski-Saari, Sarita; Kontunen-Soppela, Sari; Oksanen, Elina; Keinänen, Markku

    2016-07-01

    Air humidity indicated as vapour pressure deficit (VPD) is directly related to transpiration and stomatal function of plants. We studied the effects of VPD and nitrogen (N) supply on leaf metabolites, plant growth, and mineral nutrition with young micropropagated silver birches (Betula pendula Roth.) in a growth chamber experiment. Plants that were grown under low VPD for 26 d had higher biomass, larger stem diameter, more leaves, fewer fallen leaves, and larger total leaf area than plants that were grown under high VPD. Initially, low VPD increased height growth rate and stomatal conductance; however, the effect was transient and the differences between low and high VPD plants became smaller with time. Metabolic adjustment to low VPD reflected N deficiency. The concentrations of N, iron, chlorophyll, amino acids, and soluble carbohydrates were lower and the levels of starch, quercetin glycosides, and raffinose were higher in the leaves that had developed under low VPD compared with high VPD. Additional N supply did not fully overcome the negative effect of low VPD on nutrient status but it diminished the effects of low VPD on leaf metabolism. Thus, with high N supply, the glutamine to glutamate ratio and starch production under low VPD became comparable with the levels under high VPD. The present study demonstrates that low VPD affects carbon and nutrient homeostasis and modifies N allocation of plants.

  9. Detection of Malware and Malicious Executables Using E-Birch Algorithm

    Directory of Open Access Journals (Sweden)

    Dr. Ashit Kumar Dutta

    2016-01-01

    Full Text Available Malware detection is one of the challenges to the modern computing world. Web mining is the subset of data mining used to provide solutions for complex problems. Web intelligence is the new hope for the field of computer science to bring solution for the malware detection. Web mining is the method of web intelligence to make web as an intelligent tool to combat malware and phishing websites. Generally, malware injected through websites into the user system and modifies the executable file and paralyze the whole activity of the system. Antivirus application utilizes the data mining technique to find the malware in the web. There is a need of heuristic approach to solve the malware problem. Dynamic analysis methods yield better result than the static methods. Data mining is the best option for the dynamic analysis of malware or malicious program. The purpose of the research is to apply the enhanced Birch algorithm to find the malware and modified executables of Windows and Android operating system.

  10. Artificially decreased vapour pressure deficit in field conditions modifies foliar metabolite profiles in birch and aspen.

    Science.gov (United States)

    Lihavainen, Jenna; Keinänen, Markku; Keski-Saari, Sarita; Kontunen-Soppela, Sari; Sõber, Anu; Oksanen, Elina

    2016-07-01

    Relative air humidity (RH) is expected to increase in northern Europe due to climate change. Increasing RH reduces the difference of water vapour pressure deficit (VPD) between the leaf and the atmosphere, and affects the gas exchange of plants. Little is known about the effects of decreased VPD on plant metabolism, especially under field conditions. This study was conducted to determine the effects of artificially decreased VPD on silver birch (Betula pendula Roth.) and hybrid aspen (Populus tremula L.×P. tremuloides Michx.) foliar metabolite and nutrient profiles in a unique free air humidity manipulation (FAHM) field experiment during the fourth season of humidity manipulation, in 2011. Long-term exposure to decreased VPD modified nutrient homeostasis in tree leaves, as demonstrated by a lower N concentration and N:P ratio in aspen leaves, and higher Na concentration and lower K:Na ratio in the leaves of both species in decreased VPD than in ambient VPD. Decreased VPD caused a shift in foliar metabolite profiles of both species, affecting primary and secondary metabolites. Metabolic adjustment to decreased VPD included elevated levels of starch and heptulose sugars, sorbitol, hemiterpenoid and phenolic glycosides, and α-tocopherol. High levels of carbon reserves, phenolic compounds, and antioxidants under decreased VPD may modify plant resistance to environmental stresses emerging under changing climate.

  11. The influence of recombinant production on the immunologic behavior of birch pollen isoallergens.

    Directory of Open Access Journals (Sweden)

    Michael Wallner

    Full Text Available BACKGROUND: Allergic reactions towards the birch major pollen allergen Bet v 1 are among the most common causes of spring pollinosis in the temperate climate zone of the Northern hemisphere. Natural Bet v 1 is composed of a complex mixture of different isoforms. Detailed analysis of recombinant Bet v 1 isoforms revealed striking differences in immunologic as well as allergenic properties of the molecules, leading to a classification of Bet v 1 isoforms into high, medium, and low IgE binding proteins. Especially low IgE binding Bet v 1 isoforms have been described as ideal candidates for desensitizing allergic patients with allergen specific immunotherapy (SIT. Since diagnosis and therapy of allergic diseases are highly dependent on recombinant proteins, continuous improvement of protein production is an absolute necessity. METHODOLOGY: Therefore, two different methods for recombinant production of a low IgE binding Bet v 1 isoform were applied; one based on published protocols, the other by implementing latest innovations in protein production. Both batches of Bet v 1.0401 were extensively characterized by an array of physicochemical as well as immunological methods to compare protein primary structure, purity, quantity, folding, aggregation state, thermal stability, and antibody binding capacity. CONCLUSION: The experiments demonstrated that IgE antibody binding properties of recombinant isoallergens can be significantly influenced by the production method directly affecting possible clinical applications of the molecules.

  12. Fungal Assemblages in Different Habitats in an Erman’s Birch Forest

    Science.gov (United States)

    Yang, Teng; Sun, Huaibo; Shen, Congcong; Chu, Haiyan

    2016-01-01

    Recent meta-analyses of fungal diversity using deeply sequenced marker genes suggest that most fungal taxa are locally distributed. However, little is known about the extent of overlap and niche partitions in total fungal communities or functional guilds within distinct habitats on a local forest scale. Here, we compared fungal communities in endosphere (leaf interior), phyllosphere (leaf interior and associated surface area) and soil samples from an Erman’s birch forest in Changbai Mountain, China. Community structures were significantly differentiated in terms of habitat, with soil having the highest fungal richness and phylogenetic diversity. Endophytic and phyllosphere fungi of Betula ermanii were more phylogenetically clustered compared with the corresponding soil fungi, indicating the ability of that host plants to filter and select their fungal partners. Furthermore, the majority of soil fungal taxa were soil specialists, while the dominant endosphere and phyllosphere taxa were aboveground generalists, with soil and plant foliage only sharing forest were strictly niche specialized and constrained by weak migration among habitats. The findings suggest that phylogenetic relatedness and functional guilds’ assignment can effectively interpret the certain ecological processes. PMID:27625646

  13. Suspendable macromolecules are responsible for ice nucleation activity of birch and conifer pollen

    Directory of Open Access Journals (Sweden)

    B. G. Pummer

    2012-03-01

    Full Text Available The ice nucleation of bioaerosols (bacteria, pollen, spores, etc. is a topic of growing interest, since their impact on ice cloud formation and thus on radiative forcing, an important parameter in global climate, is not yet fully understood. Here we show that pollen of different species strongly differ in their ice nucleation behaviour. The average freezing temperatures in laboratory experiments range from 240 to 255 K. As the most efficient nuclei (silver birch, Scots pine and common juniper pollen have a distribution area up to the Northern timberline, their ice nucleation activity might be a cryoprotective mechanism. Far more intriguingly, it has turned out that water, which has been in contact with pollen and then been separated from the bodies, nucleates as good as the pollen grains themselves. The ice nuclei have to be easily-suspendable macromolecules located on the pollen. Once extracted, they can be distributed further through the atmosphere than the heavy pollen grains and so presumably augment the impact of pollen on ice cloud formation even in the upper troposphere. Our experiments lead to the conclusion that pollen ice nuclei, in contrast to bacterial and fungal ice nucleating proteins, are non-proteinaceous compounds.

  14. Methane consumption and soil respiration by a birch forest soil in West Siberia

    International Nuclear Information System (INIS)

    Methane and carbon dioxide fluxes were measured in a birch forest soil in West Siberia, in August 1999, June 2000 and September 2000. The study site had a very thick organic horizon that was subject to drought during the observation periods. The soils always took up CH4, while CO2 was released from the surface to the atmosphere. CH4 consumption and CO2 emission rates ranged from 0.092 to 0.28 mg C/m2/h and from 110 to 400 mg C/m2/h respectively. The CH4 consumption rate and soil temperatures showed significant relationships for individual measurements. The soil respiration rate was weakly correlated with individual soil temperatures. This study examined the effect of current and lagged soil temperatures at a depth of 5 cm on CH4 consumption and soil respiration. The variation in the correlation coefficient between CH4 consumption and lagged soil temperature was greatest at a 4-h lag, whereas that for soil respiration showed a gentle peak at lags from several hours to half a day. This difference in the temperature-related lag effect between CH4 consumption and soil respiration results from differences in the exchange processes. Neither flux showed any correlation with soil moisture. The limited variation in soil moisture during our observation period may account for the lack of correlation. However, the droughty soil conditions resulted in high gas diffusion and, consequently, high CH4 consumption

  15. Climate warming feedback from mountain birch forest expansion: reduced albedo dominates carbon uptake.

    Science.gov (United States)

    de Wit, Heleen A; Bryn, Anders; Hofgaard, Annika; Karstensen, Jonas; Kvalevåg, Maria M; Peters, Glen P

    2014-07-01

    Expanding high-elevation and high-latitude forest has contrasting climate feedbacks through carbon sequestration (cooling) and reduced surface reflectance (warming), which are yet poorly quantified. Here, we present an empirically based projection of mountain birch forest expansion in south-central Norway under climate change and absence of land use. Climate effects of carbon sequestration and albedo change are compared using four emission metrics. Forest expansion was modeled for a projected 2.6 °C increase in summer temperature in 2100, with associated reduced snow cover. We find that the current (year 2000) forest line of the region is circa 100 m lower than its climatic potential due to land-use history. In the future scenarios, forest cover increased from 12% to 27% between 2000 and 2100, resulting in a 59% increase in biomass carbon storage and an albedo change from 0.46 to 0.30. Forest expansion in 2100 was behind its climatic potential, forest migration rates being the primary limiting factor. In 2100, the warming caused by lower albedo from expanding forest was 10 to 17 times stronger than the cooling effect from carbon sequestration for all emission metrics considered. Reduced snow cover further exacerbated the net warming feedback. The warming effect is considerably stronger than previously reported for boreal forest cover, because of the typically low biomass density in mountain forests and the large changes in albedo of snow-covered tundra areas. The positive climate feedback of high-latitude and high-elevation expanding forests with seasonal snow cover exceeds those of afforestation at lower elevation, and calls for further attention of both modelers and empiricists. The inclusion and upscaling of these climate feedbacks from mountain forests into global models is warranted to assess the potential global impacts.

  16. BVOC responses to realistic nitrogen fertilization and ozone exposure in silver birch.

    Science.gov (United States)

    Carriero, G; Brunetti, C; Fares, S; Hayes, F; Hoshika, Y; Mills, G; Tattini, M; Paoletti, E

    2016-06-01

    Emission of BVOC (Biogenic Volatile Organic Compounds) from plant leaves in response to ozone exposure (O3) and nitrogen (N) fertilization is poorly understood. For the first time, BVOC emissions were explored in a forest tree species (silver birch, Betula pendula) exposed for two years to realistic levels of O3 (35, 48 and 69 ppb as daylight average) and N (10, 30 and 70 kg ha(-1) yr(-1), applied weekly to the soil as ammonium nitrate). The main BVOCs emitted were: α-pinene, β-pinene, limonene, ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexanal. Ozone exposure increased BVOC emission and reduced total leaf area. The effect on emission was stronger when a short-term O3 metric (concentrations at the time of sampling) rather than a long-term one (AOT40) was used. The effect of O3 on total leaf area was not able to compensate for the stimulation of emission, so that responses to O3 at leaf and whole-plant level were similar. Nitrogen fertilization increased total leaf area, decreased α-pinene and β-pinene emission, and increased ocimene, hexanal and DMNT emission. The increase of leaf area changed the significance of the emission response to N fertilization for most compounds. Nitrogen fertilization mitigated the effects of O3 exposure on total leaf area, while the combined effects of O3 exposure and N fertilization on BVOC emission were additive and not synergistic. In conclusion, O3 exposure and N fertilization have the potential to affect global BVOC via direct effects on plant emission rates and changes in leaf area. PMID:26809503

  17. Distribution and turnover of 137Cs in birch forest ecosystems: influence of precipitation chemistry

    International Nuclear Information System (INIS)

    The aim of the present work was to study radioactive caesium in soil and plants from birch forests subject to different chemical climate. Four areas and three types of precipitation regimes were considered, representing a natural climatic range found in Norway: (A) acidic precipitation (southernmost part of the country); (B) precipitation rich in “sea salts”/marine cations (coastal areas); and (C) + (D) low concentrations of sea salts (inland areas). The results showed significant regional differences in plant uptake between the investigated areas. For instance the aggregated soil-to-plant transfer coefficients (Tag) were generally up to 7–8 times higher for the area receiving acid rain. Differences in caesium speciation partly explained the regional variability - e.g. the exchangeable fraction ranged from 1 to 40% (with the largest fraction of exchangeable caesium found in southernmost Norway). Transfer coefficients estimated on the basis of exchangeable fractions showed no significant differences between the areas of highest (A) and lowest (C) Tags. However, exchangeable fractions taken into consideration, the uptake of 137Cs in plants in the acid rain-influenced area is still about twice that in the sea salt influenced area B. A significantly lower concentration of soluble base cations and a higher share of acid components in soils in area A is a likely explanation for this observation. - Highlights: ► Precipitation quality affects soil chemistry and plant uptake of Cs. ► Soil-to-plant transfer of Cs was highest in a coastal area receiving acid rain. ► Differences in Cs speciation partly explained regional transfer variability.

  18. BVOC responses to realistic nitrogen fertilization and ozone exposure in silver birch.

    Science.gov (United States)

    Carriero, G; Brunetti, C; Fares, S; Hayes, F; Hoshika, Y; Mills, G; Tattini, M; Paoletti, E

    2016-06-01

    Emission of BVOC (Biogenic Volatile Organic Compounds) from plant leaves in response to ozone exposure (O3) and nitrogen (N) fertilization is poorly understood. For the first time, BVOC emissions were explored in a forest tree species (silver birch, Betula pendula) exposed for two years to realistic levels of O3 (35, 48 and 69 ppb as daylight average) and N (10, 30 and 70 kg ha(-1) yr(-1), applied weekly to the soil as ammonium nitrate). The main BVOCs emitted were: α-pinene, β-pinene, limonene, ocimene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) and hexanal. Ozone exposure increased BVOC emission and reduced total leaf area. The effect on emission was stronger when a short-term O3 metric (concentrations at the time of sampling) rather than a long-term one (AOT40) was used. The effect of O3 on total leaf area was not able to compensate for the stimulation of emission, so that responses to O3 at leaf and whole-plant level were similar. Nitrogen fertilization increased total leaf area, decreased α-pinene and β-pinene emission, and increased ocimene, hexanal and DMNT emission. The increase of leaf area changed the significance of the emission response to N fertilization for most compounds. Nitrogen fertilization mitigated the effects of O3 exposure on total leaf area, while the combined effects of O3 exposure and N fertilization on BVOC emission were additive and not synergistic. In conclusion, O3 exposure and N fertilization have the potential to affect global BVOC via direct effects on plant emission rates and changes in leaf area.

  19. Elevated air humidity affects hydraulic traits and tree size but not biomass allocation in young silver birches (Betula pendula

    Directory of Open Access Journals (Sweden)

    Arne eSellin

    2015-10-01

    Full Text Available As changes in air temperature, precipitation, and air humidity are expected in the coming decades, studies on the impact of these environmental shifts on plant growth and functioning are of major importance. Greatly understudied aspects of climate change include consequences of increasing air humidity on forest ecosystems, predicted for high latitudes. The main objective of this study was to find a link between hydraulic acclimation and shifts in trees’ resource allocation in silver birch (Betula pendula Roth in response to elevated air relative humidity (RH. A second question was whether the changes in hydraulic architecture depend on tree size. Two years of application of increased RH decreased the biomass accumulation in birch saplings, but the biomass partitioning among aboveground parts (leaves, branches, and stems remained unaffected. Increased stem Huber values (xylem cross-sectional area to leaf area ratio observed in trees under elevated RH did not entail changes in the ratio of non-photosynthetic to photosynthetic tissues. The reduction of stem-wood density is attributable to diminished mechanical load imposed on the stem, since humidified trees had relatively shorter crowns. Growing under higher RH caused hydraulic conductance of the root system (KR to increase, while KR (expressed per unit leaf area decreased and leaf hydraulic conductance increased with tree size. Saplings of silver birch acclimate to increasing air humidity by adjusting plant morphology (live crown length, slenderness, specific leaf area, and fine-root traits and wood density rather than biomass distribution among aboveground organs. The treatment had a significant effect on several hydraulic properties of the trees, while the shifts were largely associated with changes in tree size but not in biomass allocation.

  20. Research on the Preparation of PF Adhesives by Birch Liquefaction%桦木液化制备PF的研究

    Institute of Scientific and Technical Information of China (English)

    李杉; 张真真

    2011-01-01

    The effects of the mass ratio of phenol to birch powder, quantity of NaOH, molar ratio of formaldehyde to phenol on the properties of PF resins. As indicated by the results,the impact of those factors on the performance of PF reduced as molar ratio of formaldehyde to phenol > mass ratio of phenol to birch powder > quantity of NaOH. Optimum condition for PF resin was determined through orthogonal experiment. The optimum preparation conditions were as follows: molar ratio of formaldehyde to phenol was 2.4,and mass ratio of phenol to birch powder was 4,quantity of NaOH was 12 g. By optimizing the synthesis process, PF resins were finally got, and then a pressure plate test was conducted on the PF resins,which indicated that the bonding strengths of these panels have reached GB/T9846-2004 Ⅰ.%探讨了苯酚与桦木粉质量比(液比)、NaOH用量、苯酚与甲醛摩尔比等对酚醛树脂性能的影响,结果表明,影响酚醛树脂性能的主次依次为甲醛与苯酚摩尔比>苯酚与木粉质量比(液比)>NaOH用量,木材液化物制备酚醛树脂的最佳工艺条件:苯酚与木粉质量比为4,甲醛与苯酚摩尔比为2.4,NaOH用量为12 g.并对制得的酚醛树脂进行压板测试,结果表明,胶合板的胶合强度达到了国家标GB/T9846-2004 Ⅰ类胶合板要求.

  1. Perinatal maternal administration of Lactobacillus paracasei NCC 2461 prevents allergic inflammation in a mouse model of birch pollen allergy.

    Directory of Open Access Journals (Sweden)

    Irma Schabussova

    Full Text Available BACKGROUND: The hygiene hypothesis implies that microbial agents including probiotic bacteria may modulate foetal/neonatal immune programming and hence offer effective strategies for primary allergy prevention; however their mechanisms of action are poorly understood. We investigated whether oral administration of Lactobacillus paracasei NCC 2461 to mothers during gestation/lactation can protect against airway inflammation in offspring in a mouse model of birch pollen allergy, and examined the immune mechanisms involved. METHODS: BALB/c mice were treated daily with L. paracasei in drinking water or drinking water alone in the last week of gestation and during lactation. Their offspring were sensitized with recombinant Bet v 1, followed by aerosol challenge with birch pollen extract. RESULTS: Maternal exposure to L. paracasei prevented the development of airway inflammation in offspring, as demonstrated by attenuation of eosinophil influx in the lungs; reduction of IL-5 levels in bronchoalveolar lavage, and in lung and mediastinal lymph node cell cultures; and reduced peribronchial inflammatory infiltrate and mucus hypersecretion. While allergen-specific IgE and IgG antibody levels remained unchanged by the treatment, IL-4 and IL-5 production in spleen cell cultures were significantly reduced upon allergen stimulation in offspring of L. paracasei treated mice. Offspring of L. paracasei supplemented mothers had significantly reduced Bet v 1-specific as well as Concanavalin A-induced responses in spleen and mesenteric lymph node cell cultures, suggesting the modulation of both antigen-specific and mitogen-induced immune responses in offspring. These effects were associated with increased Foxp3 mRNA expression in the lungs and increased TGF-beta in serum. CONCLUSION: Our data show that in a mouse model of birch pollen allergy, perinatal administration of L. paracasei NCC 2461 to pregnant/lactating mothers protects against the development of airway

  2. Velocity-density systematics of liquid indium and the validity of the Birch's law for a liquid metal

    Science.gov (United States)

    Kato, J.; Komabayashi, T.; Hirose, K.; Baron, A. Q.; Tsutsui, S.; Ohishi, Y.

    2011-12-01

    The Earth's core is composed mostly of iron with some amounts of light element(s). In order to put constraints on the composition of the core, high-pressure (P) and -temperature (T) elastic properties and density of both solid and liquid iron and iron compounds are of quite importance. The Birch's law which suggests that the compressional velocity would change linearly with density, has been applied to the discussion of the core composition, since it does not require temperature of the core which is one of the most difficult parameters to constrain. Assuming the Birch's law, 300-K compression experiments of solid iron or iron compounds in a diamond anvil cell (DAC) can directly address the velocity-density relations of the inner core. On the other hand, the velocity-density relation for liquid iron has not been studied in the DAC since it requires high-temperatures. Here we investigated both velocity and density of a liquid metal, in order to study the validity of the Birch's law for the liquid metal. Since the melting temperature of iron is very high, we chose indium whose melting temperature is 430 K at 1 bar. For sound velocity measurements of liquid indium, we conducted inelastic X-ray scattering measurements in an externally heated DAC. The inelastic X-ray scattering measurements were conducted at the BL35XU, SPring-8 (Japan). We collected the data of solid and liquid phases at 10 different pressure and temperature conditions. The maximum P-T condition was 9 GPa and 750 K. The melting was confirmed by the two dimensional X-ray diffraction images. For density measurements, in-situ X-ray absorption experiments in the externally heated DAC were conducted at the BL10XU, SPring-8. Dual holes are drilled in the rhenium gasket and each hole was filled with either indium or NaCl. X-ray transmission intensities were measured by a photodiode across the sample and the standard material (NaCl). Assuming the Lambert-Beer law, we estimated the density of liquid indium up to

  3. Responses in the start of Betula (birch) pollen seasons to recent changes in spring temperatures across Europe

    Science.gov (United States)

    Emberlin, J.; Detandt, M.; Gehrig, R.; Jaeger, S.; Nolard, N.; Rantio-Lehtimäki, A.

    2002-07-01

    A shift in the timing of birch pollen seasons is important because it is well known to be a significant aeroallergen, especially in NW Europe where it is a notable cause of hay fever and pollen-related asthma. The research reported in this paper aims to investigate temporal patterns in the start dates of Betula (birch) pollen seasons at selected sites across Europe. In particular it investigates relationships between the changes in start dates and changes in spring temperatures over approximately the last 20 years. Daily birch pollen counts were used from Kevo, Turku, London, Brussels, Zurich and Vienna, for the core period from 1982 to 1999 and, in some cases, from 1970 to 2000. The sites represent a range of biogeographical situations from just within the Arctic Circle through to North West Maritime and Continental Europe. Pollen samples were taken with Hirst-type volumetric spore traps. Weather data were obtained from the sites nearest to the pollen traps. The timing of birch pollen seasons is known to depend mostly on a non-linear balance between the winter chilling required to break dormancy, and spring temperatures. Pollen start dates and monthly mean temperatures for January through to May were compiled to 5-year running means to examine trends. The start dates for the next 10 years were calculated from regression equations for each site, on the speculative basis that the current trends would continue. The analyses show regional contrasts. Kevo shows a marked trend towards cooler springs and later starts. If this continues the mean start date will become about 6 days later over the next 10 years. Turku exhibits cyclic patterns in start dates. A current trend towards earlier starts is expected to continue until 2007, followed by another fluctuation. London, Brussels, Zurich and Vienna show very similar patterns in the trends towards earlier start dates. If the trend continues the mean start dates at these sites will advance by about 6 days over the next 10

  4. Soil moisture increment as a controlling variable of the Birch effect . Interactions with the pre-wetting soil moisture and litter addition

    OpenAIRE

    Lado Monserrat, Luis; Lull Noguera, Cristina; Bautista Carrascosa, María Inmaculada; Lidón Cerezuela, Antonio Luis; Herrera Fernandez, Rafael

    2014-01-01

    The Birch effect is a pulse in soil C and N mineralization caused by the wetting of dry soils, but the role of the soil moisture increment (Delta SWC) is still poorly understood. We quantified the relationship between Delta SWC and the Birch effect, and its interactions with pre-wetting soil moisture (preSWC) and substrate supply. Two soils (clay loam and sandy loam) under a Pinus halepensis forest were subjected to rewetting in laboratory treatments combining different Delta SWC and preSWC v...

  5. Leaf surface lipophilic compounds as one of the factors of silver birch chemical defense against larvae of gypsy moth.

    Directory of Open Access Journals (Sweden)

    Vyacheslav V Martemyanov

    Full Text Available Plant chemical defense against herbivores is a complex process which involves a number of secondary compounds. It is known that the concentration of leaf surface lipophilic compounds (SLCs, particularly those of flavonoid aglycones are increased with the defoliation treatment of silver birch Betula pendula. In this study we investigated how the alteration of SLCs concentration in the food affects the fitness and innate immunity of the gypsy moth Lymantria dispar. We found that a low SLCs concentrations in consumed leaves led to a rapid larval development and increased females' pupae weight (= fecundity compared to larvae fed with leaves with high SLCs content. Inversely, increasing the compounds concentration in an artificial diet produced the reverse effects: decreases in both larval weight and larval survival. Low SLCs concentrations in tree leaves differently affected larval innate immunity parameters. For both sexes, total hemocytes count in the hemolymph increased, while the activity of plasma phenoloxidase decreased when larvae consume leaves with reduced content of SLCs. Our results clearly demonstrate that the concentration of SLCs in silver birch leaves affects not only gypsy moth fitness but also their innate immune status which might alter the potential resistance of insects against infections and/or parasitoids.

  6. Genome-scale transcriptome analysis in response to nitric oxide in birch cells: implications of the triterpene biosynthetic pathway.

    Science.gov (United States)

    Zeng, Fansuo; Sun, Fengkun; Li, Leilei; Liu, Kun; Zhan, Yaguang

    2014-01-01

    Evidence supporting nitric oxide (NO) as a mediator of plant biochemistry continues to grow, but its functions at the molecular level remains poorly understood and, in some cases, controversial. To study the role of NO at the transcriptional level in Betula platyphylla cells, we conducted a genome-scale transcriptome analysis of these cells. The transcriptome of untreated birch cells and those treated by sodium nitroprusside (SNP) were analyzed using the Solexa sequencing. Data were collected by sequencing cDNA libraries of birch cells, which had a long period to adapt to the suspension culture conditions before SNP-treated cells and untreated cells were sampled. Among the 34,100 UniGenes detected, BLASTX search revealed that 20,631 genes showed significant (E-values≤10-5) sequence similarity with proteins from the NR-database. Numerous expressed sequence tags (i.e., 1374) were identified as differentially expressed between the 12 h SNP-treated cells and control cells samples: 403 up-regulated and 971 down-regulated. From this, we specifically examined a core set of NO-related transcripts. The altered expression levels of several transcripts, as determined by transcriptome analysis, was confirmed by qRT-PCR. The results of transcriptome analysis, gene expression quantification, the content of triterpenoid and activities of defensive enzymes elucidated NO has a significant effect on many processes including triterpenoid production, carbohydrate metabolism and cell wall biosynthesis.

  7. Effective Method of Purification of Betulin from Birch Bark: The Importance of Its Purity for Scientific and Medicinal Use.

    Science.gov (United States)

    Šiman, Pavel; Filipová, Alžběta; Tichá, Alena; Niang, Mohamed; Bezrouk, Aleš; Havelek, Radim

    2016-01-01

    A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH)2 in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use.

  8. HYDROGEN PEROXIDE BLEACHING OF HARDWOOD KRAFT PULP WITH ADSORBED BIRCH XYLAN AND ITS EFFECT ON PAPER PROPERTIES

    Directory of Open Access Journals (Sweden)

    Hyejung Youn

    2011-02-01

    Full Text Available The adsorption of xylan on pulp fibers improves the strength properties of paper. However, the optical properties are decreased significantly. The objective of our research was to bleach hardwood kraft pulp with adsorbed birch xylan by hydrogen peroxide and study the effect of bleaching parameters on paper properties. The bleaching parameters studied included bleaching temperature, time, initial pH as well as MgSO4 dosage. The optical properties (whiteness, brightness, opacity and physical properties (tensile index, tearing index, bulk of handsheets made from the pulp bleached with different process variables were measured. The results showed that better optical properties were obtained with higher bleaching temperature, longer bleaching time, and more MgSO4 dosage. Bleaching from an initial pH of 11 provided the highest brightness value. On the other hand, strength properties were improved with decreasing of the bleaching temperature, and increasing the initial pH and MgSO4 dosage. The relationship between strength properties and bleaching time varied depending on bleaching temperature. According to the results, both good mechanical properties and optical properties could be achieved when the operating parameters were controlled properly. Therefore hydrogen peroxide bleaching was proved to be a suitable method for bleaching hardwood kraft pulp with adsorption of birch xylan.

  9. Effective Method of Purification of Betulin from Birch Bark: The Importance of Its Purity for Scientific and Medicinal Use.

    Directory of Open Access Journals (Sweden)

    Pavel Šiman

    Full Text Available A new and relatively simple method for purification of betulin from birch bark extract was developed in this study. Its five purification steps are based on the differential solubility of extract components in various solvents and their crystallization and/or precipitation, on their affinity for Ca(OH2 in ethanol, and on the affinity of some impurities for silica gel in chloroform. In addition, all used solvents can be simply recycled. Betulin of more than 99% purity can be prepared by this method with minimal costs. Various observations including crystallization of betulin, changes in crystals during heating, and attempt of localization of betulin in outer birch bark are also described in this work. The original extract, fraction without betulinic acid and lupeol, amorphous fraction of pure betulin, final crystalline fraction of pure betulin and commercial betulin as a standard were employed to determine the antiproliferative/cytotoxic effect. We used WST-1 tetrazolium-based assays with triple negative breast cancer cell line BT-549. The decrease in cell survival showed clear relationship with the purity of the samples, being most pronounced using our final product of pure crystalline betulin. WST-1 proliferation/cytotoxicity test using triple negative breast cancer cell line BT-549 clearly showed the importance of purity of betulin for biological experiments and, apparently, for its medicinal use.

  10. Competition and facilitation in industrial barrens: variation in performance of mountain birch seedlings with distance from nurse plants.

    Science.gov (United States)

    Eränen, Janne K; Kozlov, Mikhail V

    2007-04-01

    In stressful environments inter-plant facilitation is an important phenomenon co-occurring with competition. However, most experiments in natural ecosystems have only contrasted "sheltered" and "exposed" microsites, thus missing possible non-linearity of effects and not giving any information about the scale at which these interactions operate. In the current experiment we studied the net effect of nurse trees on mountain birch seedlings at various planting distances. Seedlings were planted in two highly stressful subarctic industrial barren sites around the nickel-copper smelter in Monchegorsk, NW Russia, at five distances (from 10 to 100 cm) from mature birch trees that were circa 100 cm in height. The survival and growth of seedlings were monitored for six years and the results were analyzed in respect to several environmental characteristics. Despite the fact that interaction strengths varied between years and between two study sites, both survival and growth of seedlings indicated optimum performance at middle distances and decreasing performance closer to and further from the nurse tree. We suggest that adverse effects on seedling performance at short distances are explained by competition and/or accumulation of pollutants under nurse plants, whereas at long distances these adverse effects appear due to lack of shelter, as shown by higher wind stress and lower soil water content. PMID:17234245

  11. A Preliminary Pharmacokinetic Study of Betulin, the Main Pentacyclic Triterpene from Extract of Outer Bark of Birch (Betulae alba cortex

    Directory of Open Access Journals (Sweden)

    Melanie N. Laszczyk

    2008-12-01

    Full Text Available During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 μg/mL respectively, for pharmacokinetic studies it was suspended in sesame oil (rats, i.p. and PEG 400 / 0.9 % NaCl (dogs, s.c.. I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 μg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 μg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p. and dogs (s.c.. In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.

  12. How does solar ultraviolet-B radiation improve drought tolerance of silver birch (Betula pendula Roth.) seedlings?

    Science.gov (United States)

    Robson, T Matthew; Hartikainen, Saara M; Aphalo, Pedro J

    2015-05-01

    We hypothesized that solar ultraviolet (UV) radiation would protect silver birch seedlings from the detrimental effects of water stress through a coordinated suite of trait responses, including morphological acclimation, improved control of water loss through gas exchange and hydraulic sufficiency. To better understand how this synergetic interaction works, plants were grown in an experiment under nine treatment combinations attenuating ultraviolet-A and ultraviolet-B (UVB) from solar radiation together with differential watering to create water-deficit conditions. In seedlings under water deficit, UV attenuation reduced height growth, leaf production and leaf length compared with seedlings receiving the full spectrum of solar radiation, whereas the growth and morphology of well-watered seedlings was largely unaffected by UV attenuation. There was an interactive effect of the treatment combination on water relations, which was more apparent as a change in the water potential at which leaves wilted or plants died than through differences in gas exchange. This suggests that changes occur in the cell wall elastic modulus or accumulation of osmolites in cells under UVB. Overall, the strong negative effects of water deficit are partially ameliorated by solar UV radiation, whereas well-watered silver birch seedlings are slightly disadvantaged by the solar UV radiation they receive.

  13. Genome-scale transcriptome analysis in response to nitric oxide in birch cells: implications of the triterpene biosynthetic pathway.

    Directory of Open Access Journals (Sweden)

    Fansuo Zeng

    Full Text Available Evidence supporting nitric oxide (NO as a mediator of plant biochemistry continues to grow, but its functions at the molecular level remains poorly understood and, in some cases, controversial. To study the role of NO at the transcriptional level in Betula platyphylla cells, we conducted a genome-scale transcriptome analysis of these cells. The transcriptome of untreated birch cells and those treated by sodium nitroprusside (SNP were analyzed using the Solexa sequencing. Data were collected by sequencing cDNA libraries of birch cells, which had a long period to adapt to the suspension culture conditions before SNP-treated cells and untreated cells were sampled. Among the 34,100 UniGenes detected, BLASTX search revealed that 20,631 genes showed significant (E-values≤10-5 sequence similarity with proteins from the NR-database. Numerous expressed sequence tags (i.e., 1374 were identified as differentially expressed between the 12 h SNP-treated cells and control cells samples: 403 up-regulated and 971 down-regulated. From this, we specifically examined a core set of NO-related transcripts. The altered expression levels of several transcripts, as determined by transcriptome analysis, was confirmed by qRT-PCR. The results of transcriptome analysis, gene expression quantification, the content of triterpenoid and activities of defensive enzymes elucidated NO has a significant effect on many processes including triterpenoid production, carbohydrate metabolism and cell wall biosynthesis.

  14. Food sensitivity reported by patients with asthma and hay fever. A relationship between food sensitivity and birch pollen-allergy and between food sensitivity and acetylsalicylic acid intolerance.

    Science.gov (United States)

    Eriksson, N E

    1978-08-01

    Among adult patients with bronchial asthma and/or allergic rhinitis undergoing allergological investigation with skin test, nasal provocation test and RAST, 1129 answered a questionaire regarding food sensitivity (FS). 276 (24%) of the patients reported some kind of allergic symptoms on eating or handling various foods, of which hazel nut, apple and shell fish were the most often named. Females reported FS more often than males. A correlation was found between birch pollen allergy and FS with nuts, apple, peach, cherry, pear, plum, carrot and new potato. The higher the degree of birch pollen allergy, according to skin test, RAST or provocation test, the higher the frequency of FS. A correlation was found too between acetylsalicylic acid intolerance and FS with some foods, e.g. nuts, strawberry, almond, green pepper, hip, chocolate, egg, cabbage, milk and wine. The connection between birch pollen allergy and FS is probably explained by the structural relationship between birch pollen allergen and some allergens of the foodstuffs, whereas the high incidence of FS in acetylsalicylic acid-intolerant patients is probably explained by additives in foods as well as salicylates or benzoates naturally occurring in some food. PMID:717703

  15. Ozone and climate - Effects of the excess of critical loads on birches and mountain plants; Ozon og klima - effekter av taalegrenseoverskridelser paa bjoerk og fjellplanter

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, L.M.

    1996-01-01

    The conference paper relates to the environmental effects of high concentrated ozone on the biomass production in Norway. The effects on birches and mountain plants from ozone together with the interaction between ozone and carbon dioxide and their influence on vegetation are discussed

  16. Long-term development of experimental mixtures of Scots pine (Pinus sylvestris L. and silver birch (Betula pendula Roth. in northern Britain

    Directory of Open Access Journals (Sweden)

    Bill Mason

    2016-07-01

    Full Text Available The Caledonian pinewoods of northern Scotland are a priority conservation habitat in Europe which are dominated by Scots pine (Pinus sylvestris, but varying proportions of a number of broadleaved species such as silver birch (Betula pendula can occur in these forests. Better understanding of the dynamics of mixed Scots pine-birch stands would be helpful in informing current initiatives to restore and increase the area of the pinewood ecosystem. Some evidence is provided by two experiments established in the 1960s which compared plots of pure Scots pine and pure birch with two treatments where the two species were mixed in 3:1 and 1:1 ratios. Some fifty years later, Scots pine was the more vigorous of the two species in these experiments, being both taller and significantly larger in diameter. The highest basal area was generally found in the pure Scots pine plots and the values in the mixed plots tended to be intermediate between those of the two component species. Examination of the growth in the mixed plots showed a slight, but non-significant, tendency towards overyielding. This appeared to be due to Scots pine growth being better than predicted, while that of birch was slightly less than predicted. These results suggest that in these mixtures, which are composed of two light demanding species, the main mechanism driving long-term performance is competition for light and there is little evidence of any complementary effect. These results suggest that any strategy seeking to increase the long-term representation of broadleaves such as birch in the Caledonian pinewoods will need to create discrete blocks that are large enough to withstand the competitive pressures exerted by the pine.

  17. Overexpression of a MADS-box gene from birch (Betula platyphylla promotes flowering and enhances chloroplast development in transgenic tobacco.

    Directory of Open Access Journals (Sweden)

    Guan-Zheng Qu

    Full Text Available In this study, a MADS-box gene (BpMADS, which is an ortholog of AP1 from Arabidopsis, was isolated from birch (Betula platyphylla. Transgenic Arabidopsis containing a BpMADS promoter::GUS construct was produced, which exhibited strong GUS staining in sepal tissues. Ectopic expression of BpMADS significantly enhanced the flowering of tobacco (35S::BpMADS. In addition, the chloroplasts of transgenic tobacco exhibited much higher growth and division rates, as well rates of photosynthesis, than wild-type. A grafting experiment demonstrated that the flowering time of the scion was not affected by stock that overexpressed BpMADS. In addition, the overexpression of BpMADS resulted in the upregulation of some flowering-related genes in tobacco.

  18. Interspecific differences in foliar 1 PAHs load between Scots pine, birch, and wild rosemary from three polish peat bogs.

    Science.gov (United States)

    Mętrak, Monika; Aneta, Ekonomiuk; Wiłkomirski, Bogusław; Staszewski, Tomasz; Suska-Malawska, Małgorzata

    2016-08-01

    Pine needles are one of the most commonly used bioindicators of polycyclic aromatic hydrocarbons (PAHs) in the environment. Therefore, the main objective of the current research was the assessment of PAHs accumulation potential of Scots pine (Pinus sylvestris L.) needles in comparison to wild rosemary (Rhododendron tomentosum Harmaja) and birch (Betula spp.) leaves. Our study was carried out on three peat bogs subjected to different degree of anthropopression, which gave us also the opportunity to identify local emission sources. Pine needles had the lowest accumulation potential from all the studied species. The highest accumulation potential, and hence carcinogenic potential, was observed for wild rosemary leaves. As far as emission sources are concerned, the most pronounced influence on atmospheric PAHs loads had traditional charcoal production, resulting in great influx of heavy PAHs. Observed seasonal changes in PAHs concentrations followed the pattern of winter increase, caused mainly by heating season, and summer decrease, caused mainly by volatilization of light PAHs. PMID:27393196

  19. Degradation kinetics of the main carbohydrates in birch wood during hot water extraction in a batch reactor at elevated temperatures.

    Science.gov (United States)

    Borrega, Marc; Nieminen, Kaarlo; Sixta, Herbert

    2011-11-01

    Hot water extraction of wood at elevated temperatures may be a suitable method to produce hemicellulose-lean pulps and to recover xylan-derived products from the water extract. In this study, water extractions of birch wood were conducted at temperatures between 180 and 240 °C in a batch reactor. Xylan was extensively removed, whereas cellulose was partly degraded only at temperatures above 180 °C. Under severe extraction conditions, acetic acid content in the water extract was higher than the corresponding amount of acetyl groups in wood. In addition to oligo- and monosaccharides, considerable amounts of furfural and 5-hydroxymethylfurfural (HMF) were recovered from the extracts. After reaching a maximum, the furfural yield remained constant with increasing extraction time. This maximum slightly decreased with increasing extraction temperature, suggesting the preferential formation of secondary degradation products from xylose. Kinetic models fitting experimental data are proposed to explain degradation and conversion reactions of xylan and glucan. PMID:21967712

  20. Degradation kinetics of the main carbohydrates in birch wood during hot water extraction in a batch reactor at elevated temperatures.

    Science.gov (United States)

    Borrega, Marc; Nieminen, Kaarlo; Sixta, Herbert

    2011-11-01

    Hot water extraction of wood at elevated temperatures may be a suitable method to produce hemicellulose-lean pulps and to recover xylan-derived products from the water extract. In this study, water extractions of birch wood were conducted at temperatures between 180 and 240 °C in a batch reactor. Xylan was extensively removed, whereas cellulose was partly degraded only at temperatures above 180 °C. Under severe extraction conditions, acetic acid content in the water extract was higher than the corresponding amount of acetyl groups in wood. In addition to oligo- and monosaccharides, considerable amounts of furfural and 5-hydroxymethylfurfural (HMF) were recovered from the extracts. After reaching a maximum, the furfural yield remained constant with increasing extraction time. This maximum slightly decreased with increasing extraction temperature, suggesting the preferential formation of secondary degradation products from xylose. Kinetic models fitting experimental data are proposed to explain degradation and conversion reactions of xylan and glucan.

  1. Improved BIRCH clustering algorithm based on density%基于密度的改进BIRCH聚类算法

    Institute of Scientific and Technical Information of China (English)

    韦相

    2013-01-01

      针对传统的BIRCH算法用直径来控制聚类的边界,对非球形聚类效果不佳,甚至会把非球状的簇分割为不同簇这一缺点,对BIRCH算法进行改进,改进算法首先建立多棵CF树,每棵CF树代表一个簇,并结合DBSCAN算法的密度可达的思想。该算法能对任意形状的簇进行准确的聚类。实验表明,算法能通过一次扫描进行有效聚类,时间复杂度与BIRCH算法相同,对大规模数据集具有较高的处理速度,实现了动态聚类,并可以准确地对任意形状的簇进行聚类并发现噪声点。%The traditional BIRCH clustering algorithm has shortcoming that it is not capable enough to cluster arbitrary shapes for controlling the cluster boundary with the diameter. This paper proposes a new improved algorithm. This algorithm unifies the method of DBSCAN algorithm. And establishes many CF-trees, each tree represents one sub-cluster. The experiments show that the proposed algorithm is efficient and scalable for arbitrary shapes cluster, realizes the incremental clustering, time complexity is the same as BIRCH algorithm, and gets rid of noise.

  2. The impact of nitration on the structure and immunogenicity of the major birch pollen allergen Bet v 1.0101.

    Directory of Open Access Journals (Sweden)

    Chloé Ackaert

    Full Text Available Allergy prevalence has increased in industrialized countries. One contributing factor could be pollution, which can cause nitration of allergens exogenously (in the air or endogenously (in inflamed lung tissue. We investigated the impact of nitration on both the structural and immunological behavior of the major birch pollen allergen Bet v 1.0101 to determine whether nitration might be a factor in the increased incidence of allergy. Bet v 1.0101 was nitrated with tetranitromethane. Immune effects were assessed by measuring the proliferation of specific T-cell lines (TCLs upon stimulation with different concentrations of nitrated and unmodified allergen, and by measurement of cytokine release of monocyte-derived dendritic cells (moDCs and primary DCs (primDCs stimulated with nitrated versus unmodified allergen. HPLC-MS, crystallography, gel electrophoresis, amino acid analysis, size exclusion chromatography and molecular dynamics simulation were performed to characterize structural changes after nitration of the allergen. The proliferation of specific TCLs was higher upon stimulation with the nitrated allergen in comparison to the unmodified allergen. An important structural consequence of nitration was oligomerization. Moreover, analysis of the crystal structure of nitrated Bet v 1.0101 showed that amino acid residue Y83, located in the hydrophobic cavity, was nitrated to 100%. Both moDCs and primDCs showed decreased production of TH1-priming cytokines, thus favoring a TH2 response. These results implicate that nitration of Bet v 1.0101 might be a contributing factor to the observed increase in birch pollen allergy, and emphasize the importance of protein modifications in understanding the molecular basis of allergenicity.

  3. Genetic engineering of trimers of hypoallergenic fragments of the major birch pollen allergen, Bet v 1, for allergy vaccination.

    Science.gov (United States)

    Vrtala, Susanne; Fohr, Monika; Campana, Raffaela; Baumgartner, Christian; Valent, Peter; Valenta, Rudolf

    2011-03-01

    An immunotherapy trial performed in allergic patients with hypoallergenic recombinant fragments, comprising aa 1-74 and 75-160 of the major birch pollen allergen, Bet v 1, has indicated that the induction of allergen-specific IgG responses may be an important mechanism of this treatment. To investigate whether the immunogenicity of the rBet v 1 fragments can be increased, recombinant trimers of the fragments were produced. For this purpose, DNA trimers of rBet v 1 aa 1-74 as well as of rBet v 1 aa 75-160 were subcloned into expression plasmid pET 17b, expressed in Escherichia coli and purified. The fragments as well as the fragment trimers showed a reduced IgE-binding capacity and allergenic activity compared to rBet v 1 wildtype when tested in allergic patients. Both rBet v 1 aa 75-160 monomer and trimer induced high titers of allergen-specific IgG1 Abs in mice. Interestingly, rBet v 1 aa 1-74 trimer induced a much higher IgG(1) response to rBet v 1 than rBet v 1 aa 1-74 monomer. Consequently, IgG Abs induced with the rBet v 1 aa 1-74 trimer inhibited birch pollen allergic patients' IgE-binding 10-fold more efficiently than IgG Abs induced with the monomer. Our data show that the immunogenicity of allergy vaccines can be increased by oligomerization.

  4. A non-allergenic Ole e 1-like protein from birch pollen as a tool to design hypoallergenic vaccine candidates.

    Science.gov (United States)

    Marazuela, Eva G; Hajek, Roswitha; Villalba, Mayte; Barber, Domingo; Breiteneder, Heimo; Rodríguez, Rosalía; Batanero, Eva

    2012-02-01

    Recombinant DNA technology offers several approaches to convert allergens into hypoallergenic derivatives that can represent the basis of novel, safer and more effective forms of allergy vaccines. In this context, we used a new strategy for the design of a hypoallergenic derivative of Ole e 1, the main allergen of olive pollen. By screening a cDNA library from birch pollen, the clone BB18, encoding the birch counterpart of Ole e 1, was identified. In this study, BB18 has been produce in Pichia pastoris as a recombinant protein and immunologically characterized. The well-established non-allergenic properties of BB18 were used to generate a genetic variant of Ole e 1, named OB(55-58), by site-direct mutagenesis of four residues (E(55)V(56)G(57)Y(58)) in an IgE/IgG epitope of Ole e 1 by the corresponding ones in BB18 (SDSE). OB(55-58) was expressed in P. pastoris, purified to homogeneity and analyzed for IgE-reactivity by means of ELISA using sera from olive pollen allergic patients and rat basophil activation assay. T cell reactivity was assayed in a mouse model of Ole e 1 sensitization. The mutant OB(55-58) exhibited an impaired IgE reactivity, but not affected T cell reactivity, compared to wild type rOle e 1. This study emphasizes the usefulness of BB18 as a tool for epitope mapping and for engineering hypoallergenic derivatives of Ole e 1 as vaccine candidates for allergy prevention and treatment.

  5. Birch pollen influence the severity of atopic eczema – prospective clinical cohort pilot study and ex vivo penetration study

    Directory of Open Access Journals (Sweden)

    Fölster-Holst R

    2015-10-01

    Full Text Available Regina Fölster-Holst,1 Jagoda Galecka,1 Sigo Weißmantel,1 Ute Dickschat,2 Frank Rippke,3 Kerstin Bohnsack,3 Thomas Werfel,4 Katja Wichmann,4 Matthias Buchner,1 Thomas Schwarz,1 Annika Vogt,5 Jürgen Lademann,5 Martina C Meinke5 1Department of Dermatology, Venerology and Allergy, University of Kiel, 2Wörth, 3Beiersdorf AG, Hamburg, 4Department of Dermatology, Venerology and Allergy, Division of Immunodermatology and Allergy Research, Hannover Medical School, Hannover, 5Department of Dermatology, Venerology and Allergology, Charité – Universitätsmedizin Berlin, Berlin, Germany Abstract: There is little clinical evidence for a correlation between the severity of atopic eczema (AE and pollen exposition. To obtain more data, we performed a clinical cohort pilot study about the influence of pollen on AE between sensitized and nonsensitized subjects and an experimental study addressing the cutaneous penetration of pollen into the skin. Fifty-five patients were monitored during birch pollen season. To study the cutaneous penetration, grass pollen allergens were applied on excised skin and the uptake in CD1c-expressing dendritic cells was investigated. The correlation between environmental pollen load and severity of the Scoring Atopic Dermatitis (SCORAD score and pruritus was observed, regardless of the status of sensitization. The sensitized group recovered significantly worse after the birch pollen season. Remarkably higher amounts of pollen allergens taken up by CD1c cells were detected in epidermal cells derived from skin explants with a disturbed epidermal barrier. These findings suggest an exacerbating role of pollen in AE utilizing the epidermal route. Keywords: aeroallergens, atopic eczema, seasonality, skin antigen-presenting cells, skin barrier penetration

  6. Effect of aluminium on in vitro rooting of birch (Betula pendula Roth. and poplar (Populus tremula L. x P. alba L. microcuttings

    Directory of Open Access Journals (Sweden)

    Krystyna Bojarczuk

    2014-02-01

    Full Text Available Poplar (Populus tremula L. x P. alba L. and birch (Betula pendula Roth. microcuttings obtained from in vitro cultures on media with aluminium (Al+ or without aluminium (Al- were rooted in perlite saturated with a liquid 1/4 MS medium. Aluminium was added to the rooting medium in the form of aluminium sulphate or aluminium chloride. In the control, i.e. in the medium without aluminium, Al+ and Al- shoots usually developed similarly. Addition of aluminium to the rooting medium had a negative effect on the development of adventitious roots. Poplar and birch shoots obtained from cultures on media with aluminium (AI+ were distinguished by a greater tolerance of aluminium in the medium than shoots obtained from cultures on media without aluminium (A1-.

  7. Variability of some morphological traits of one-year old red oak, black walnut, birch and wild pear seedlings in the nurseries of Jastrebac region

    Directory of Open Access Journals (Sweden)

    Krstić Milun

    2002-01-01

    Full Text Available Five morphological and quantitative characteristics of one-year old seedlings of Red oak (Quercus rubra L, Black walnut (Juglans nigra L, Wild pear (Pyrus pygrowser Borkh and Birch (Betula verrucosa Ehrh were studied. The seedlings were produced and cultivated in the controlled conditions of the nursery in the region of Jastrebac, by the classical method. Aboveground seedling height, root collar diameter, root length, number of secondary roots and the leaf assimilation area were analysed. Intraspecific and interspecific variability of morphological features of the above species were assessed by the comparative analysis and statistical methods The comparative analysis shows the great individual variability of seedlings, which can indicate their genetic potential, adaptation to environment conditions, further spontaneous selection and the development in natural conditions. This justifies the need of the quality assessment and the first selection already in the nursery, in order to ensure the quality planting material and to reduce the risk of afforestation failure One-year old birch seedlings have the lowest average height (18.8 cm. Black walnut and Wild pear seedlings are approximately twice as high, and Red oak about 2.5 times higher. At the same time Red oak seedlings have for about one-fourth greater height than Black walnut, and for one-third greater height than Wild pear. Wild pear seedlings attain the averagely twice larger root collar diameter than Birch (2.8 cm, Red oak seedlings about 2.5 times larger diameter, and Black walnut 3.5 times larger diameter. Black walnut has a larger root collar diameter than Red oak for about one third, and almost twice larger than Wild pear. Birch, Red oak and Wild pear have almost twice longer root (1.8-1.9 times, Black walnut about 2.25 times longer. The total assimilation area of a Birch seedling is averagely 89.0 cm2. Compared to birch, wild pear has approximately double assimilation area per tree, Red

  8. Assessment of hydrology, water quality, and trace elements in selected placer-mined creeks in the birch creek watershed near central, Alaska, 2001-05

    Science.gov (United States)

    Kennedy, Ben W.; Langley, Dustin E.

    2007-01-01

    Executive Summary The U.S. Geological Survey, in cooperation with the Bureau of Land Management, completed an assessment of hydrology, water quality, and trace-element concentrations in streambed sediment of the upper Birch Creek watershed near Central, Alaska. The assessment covered one site on upper Birch Creek and paired sites, upstream and downstream from mined areas, on Frying Pan Creek and Harrison Creek. Stream-discharge and suspended-sediment concentration data collected at other selected mined and unmined sites helped characterize conditions in the upper Birch Creek watershed. The purpose of the project was to provide the Bureau of Land Management with baseline information to evaluate watershed water quality and plan reclamation efforts. Data collection began in September 2001 and ended in September 2005. There were substantial geomorphic disturbances in the stream channel and flood plain along several miles of Harrison Creek. Placer mining has physically altered the natural stream channel morphology and removed streamside vegetation. There has been little or no effort to re-contour waste rock piles. During high-flow events, the abandoned placer-mine areas on Harrison Creek will likely contribute large quantities of sediment downstream unless the mined areas are reclaimed. During 2004 and 2005, no substantial changes in nutrient or major-ion concentrations were detected in water samples collected upstream from mined areas compared with water samples collected downstream from mined areas on Frying Pan Creek and Harrison Creek that could not be attributed to natural variation. This also was true for dissolved oxygen, pH, and specific conductance-a measure of total dissolved solids. Sample sites downstream from mined areas on Harrison Creek and Frying Pan Creek had higher median suspended-sediment concentrations, by a few milligrams per liter, than respective upstream sites. However, it is difficult to attach much importance to the small downstream increase

  9. Implications of Elevated Atmospheric Carbon Dioxide and Tropospheric Ozone for Water Use in Stands of Trembling Aspen and Paper Birch

    Science.gov (United States)

    Rhea, Lee Kirk

    Projected increases in the atmospheric concentration of CO2 and tropospheric O3 over the next 50 years are of concern due in part to their potential to affect forest water budgets. I conducted a series of studies at the Aspen Free Air CO2 and O3 Enrichment experiment near Rhinelander, WI to determine the effect of projected concentrations of these gases for the year 2050 on the water budget in stands of trembling aspen and paper birch. In order to determine the effects of elevated CO2 (eCO 2) and O3 (eO3) on rainfall partitioning between interception, through fall, and stem flow I performed a computerized analysis of photographed canopy branches and compared the results to hydrologic measurements. Elevated O3 significantly decreased total aspen and birch branch length, resulting in net decreases for 2002 whorls of -18 % and 2006 whorls of -16 %. Some of these changes had measurable effects on rainfall partitioning. The biomass of fine roots has been observed to change in response to eCO2 and eO3 at shallow depths, but little work has been done to assess deeper roots. I characterized fine root responses to eCO 2 and eO3 to a depth of one meter. Fumigation with O 3 increased small root biomass in shallow soil 30 % in all aspen plots and decreased root biomass in shallow soil 46 % in aspen-birch plots. Increases in root length up to 131 % and specific root length up to 77 % occurred under eO3 in middle and deep soil layers, indicating more extensive soil exploration at depth. Small root biomass in shallow soils increased 20 % to 24 % under eCO2, indicative of more intensive soil exploration near the surface. Previous studies of sapwood from Aspen-FACE indicated that anatomical structures related to hydraulic conductance (K) differed between aspen clones and that they responded to the treatments differently. I constructed embolism curves for stem wood samples collected below the base of the live crowns. There were no significant treatment effects on K at full water

  10. Do elevations in temperature, CO2, and nutrient availability modify belowground carbon gain and root morphology in artificially defoliated silver birch seedlings?

    Science.gov (United States)

    Huttunen, Liisa; Saravesi, Karita; Markkola, Annamari; Niemelä, Pekka

    2013-09-01

    Climate warming increases the risk of insect defoliation in boreal forests. Losses in photosynthetically active surfaces cause reduction in net primary productivity and often compromise carbon reserves of trees. The concurrent effects of climate change and removal of foliage on root growth responses and carbohydrate dynamics are poorly understood, especially in tree seedlings. We investigated if exposures to different combinations of elevated temperature, CO2, and nutrient availability modify belowground carbon gain and root morphology in artificially defoliated 1-year-old silver birches (Betula pendula). We quantified nonstructural carbohydrates (insoluble starch as a storage compound; soluble sucrose, fructose, and glucose) singly and in combination in fine roots of plants under winter dormancy. Also the total mass, fine root proportion, water content, and length of roots were defined. We hypothesized that the measured properties are lower in defoliated birch seedlings that grow with ample resources than with scarce resources. On average, fertilization markedly decreased both the proportion and the carbohydrate concentrations of fine roots in all seedlings, whereas the effect of fertilization on root water content and dry mass was the opposite. However, defoliation mitigated the effect of fertilization on the root water content, as well as on the proportion of fine roots and their carbohydrate concentrations by reversing the outcomes. Elevation in temperature decreased and elevation in CO2 increased the absolute contents of total nonstructural carbohydrates, whereas fertilization alleviated both these effects. Also the root length and mass increased by CO2 elevation. This confirms that surplus carbon in birch tissues is used as a substrate for storage compounds and for cell wall synthesis. To conclude, our results indicate that some, but not all elements of climate change alter belowground carbon gain and root morphology in defoliated silver birch seedlings.

  11. Changes in the areal extents of the Athabasca River, Birch River, and Cree Creek Deltas, 1950-2014, Peace-Athabasca Delta, Canada

    Science.gov (United States)

    Timoney, Kevin; Lee, Peter

    2016-04-01

    Deltas form where riverborne sediment accumulates at the interface of river mouths and their receiving water bodies. Their areal extent is determined by the net effect of processes that increase their extent, such as sediment accumulation, and processes that decrease their extent, such as erosion and subsidence. Through sequential mapping and construction of river discharge and sediment histories, this study examined changes in the subaerial extents of the Cree Creek and Athabasca River Deltas (both on the Athabasca River system) and the Birch River Delta in northern Canada over the period 1950-2014. The purpose of the study was to determine how, when, and why the deltas changed in areal extent. Temporal growth patterns were similar across the Athabasca and Birch River systems indicative of a climatic signal. Little or no areal growth occurred from 1950 to 1968; moderate growth occurred between 1968 and the early to mid-1980s; and rapid growth occurred between 1992 and 2012. Factors that affected delta progradation included dredging, sediment supply, isostatic drowning, delta front bathymetry, sediment capture efficiency, and storms. In relation to sediment delivered, areal growth rates were lowest in the Athabasca Delta, intermediate in the Birch Delta, and highest in the Cree Creek Delta. Annual sediment delivery is increasing in the Cree Creek Delta; there were no significant trends in annual sediment delivery in the Birch and Athabasca Deltas. There was a lag of up to several years between sediment delivery events and progradation. Periods of delta progradation were associated with low water levels of the receiving basins. Predicted climate-change driven declines in river discharge and lake levels may accelerate delta progradation in the region. In the changing ecosystems of northeastern Alberta, inadequate monitoring of vegetation, landforms, and sediment regimes hampers the elucidation of the nature, rate, and causality of ecosystem changes.

  12. EXTRACTION OF BETULIN BY ALIPHATIC ALCOHOLS C3-C4 FROM AN EXTERNAL LAYER OF A BIRCH BARK HYDROLYZED IN AQUEOUS ALKALINE SOLUTION

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    Владимир Александрович Левданский

    2014-09-01

    Full Text Available It was established, that after hydrolysis of birch bark in water solution of alkali in the presence of isopropanol, butanol and isobutanol two layers were formed. The top layer contained betulin dissolved in alcohol, and the bottom layer contained a water-soluble alkali and its hydrolysis products of bark. Betulin was isolated by the separation and concentration of the alcohol layer. The structure of betulin was confirmed by methods of IR and NMR spectroscopy.

  13. Influence of the Oil Phase and Topical Formulation on the Wound Healing Ability of a Birch Bark Dry Extract.

    Directory of Open Access Journals (Sweden)

    Isabel Steinbrenner

    Full Text Available Triterpenes from the outer bark of birch are known for various pharmacological effects including enhanced wound healing (WH. A birch bark dry extract (TE obtained by accelerated solvent extraction showed the ability to form oleogels when it is suspended in oils. Consistency of the oleogels and the dissolved amount of triterpenes varies largely with the used oil. Here we wanted to know to what extent different oils and formulations (oleogel versus o/w emulsion influence WH. Looking at the plain oils, medium-chain triglycerides (MCT enhanced WH (ca. 1.4-fold, while e.g. castor oil (ca.0.3-fold or light liquid paraffin (LLP; ca. 0.5-fold significantly decreased WH. Concerning the respective oleogels, TE-MCT showed no improvement although the solubility of the TE was high. In contrast, the oleogel of sunflower oil which alone showed a slight tendency to impair WH, enhanced WH significantly (ca. 1.6-fold. These results can be explained by release experiments where the release rate of betulin, the main component of TE, from MCT oleogels was significantly lower than from sunflower oil oleogels. LLP impaired WH as plain oil and even though it released betulin comparable to sunflower oil it still results in an overall negative effect of the oleogel on WH. As a further formulation option also surfactant free o/w emulsions were prepared using MCT, sunflower oil and LLP as a nonpolar oil phase. Depending on the preparation method (suspension or oleogel method the distribution of the TE varied markedly and affected also release kinetics. However, the released betulin was clearly below the values measured with the respective oleogels. Consequently, none of the emulsions showed a significantly positive effect on WH. In conclusion, our data show that the oil used as a vehicle influences wound healing not only by affecting the release of the extract, but also by having its own vehicle effect on wound healing. This is also of importance for other applications

  14. Influence of the Oil Phase and Topical Formulation on the Wound Healing Ability of a Birch Bark Dry Extract.

    Science.gov (United States)

    Steinbrenner, Isabel; Houdek, Pia; Pollok, Simone; Brandner, Johanna M; Daniels, Rolf

    2016-01-01

    Triterpenes from the outer bark of birch are known for various pharmacological effects including enhanced wound healing (WH). A birch bark dry extract (TE) obtained by accelerated solvent extraction showed the ability to form oleogels when it is suspended in oils. Consistency of the oleogels and the dissolved amount of triterpenes varies largely with the used oil. Here we wanted to know to what extent different oils and formulations (oleogel versus o/w emulsion) influence WH. Looking at the plain oils, medium-chain triglycerides (MCT) enhanced WH (ca. 1.4-fold), while e.g. castor oil (ca.0.3-fold) or light liquid paraffin (LLP; ca. 0.5-fold) significantly decreased WH. Concerning the respective oleogels, TE-MCT showed no improvement although the solubility of the TE was high. In contrast, the oleogel of sunflower oil which alone showed a slight tendency to impair WH, enhanced WH significantly (ca. 1.6-fold). These results can be explained by release experiments where the release rate of betulin, the main component of TE, from MCT oleogels was significantly lower than from sunflower oil oleogels. LLP impaired WH as plain oil and even though it released betulin comparable to sunflower oil it still results in an overall negative effect of the oleogel on WH. As a further formulation option also surfactant free o/w emulsions were prepared using MCT, sunflower oil and LLP as a nonpolar oil phase. Depending on the preparation method (suspension or oleogel method) the distribution of the TE varied markedly and affected also release kinetics. However, the released betulin was clearly below the values measured with the respective oleogels. Consequently, none of the emulsions showed a significantly positive effect on WH. In conclusion, our data show that the oil used as a vehicle influences wound healing not only by affecting the release of the extract, but also by having its own vehicle effect on wound healing. This is also of importance for other applications where drugs

  15. Sap flux in pure aspen and mixed aspen-birch forests exposed to elevated concentrations of carbon dioxide and ozone.

    Science.gov (United States)

    Uddling, Johan; Teclaw, Ronald M; Kubiske, Mark E; Pregitzer, Kurt S; Ellsworth, David S

    2008-08-01

    Elevated concentrations of atmospheric carbon dioxide ([CO2]) and tropospheric ozone ([O3]) have the potential to affect tree physiology and structure and hence forest water use, which has implications for climate feedbacks. We investigated how a 40% increase above ambient values in [CO2] and [O3], alone and in combination, affect tree water use of pure aspen and mixed aspen-birch forests in the free air CO2-O3 enrichment experiment near Rhinelander, Wisconsin (Aspen FACE). Measurements of sap flux and canopy leaf area index (L) were made during two growing seasons, when steady-state L had been reached after more than 6 years of exposure to elevated [CO2] and [O3]. Maximum stand-level sap flux was not significantly affected by elevated [O3], but was increased by 18% by elevated [CO2] averaged across years, communities and O(3) regimes. Treatment effects were similar in pure aspen and mixed aspen-birch communities. Increased tree water use in response to elevated [CO2] was related to positive CO2 treatment effects on tree size and L (+40%). Tree water use was not reduced by elevated [O3] despite strong negative O3 treatment effects on tree size and L (-22%). Elevated [O3] predisposed pure aspen stands to drought-induced sap flux reductions, whereas increased tree water use in response to elevated [CO2] did not result in lower soil water content in the upper soil or decreasing sap flux relative to control values during dry periods. Maintenance of soil water content in the upper soil in the elevated [CO2] treatment was at least partly a function of enhanced soil water-holding capacity, probably a result of increased organic matter content from increased litter inputs. Our findings that larger trees growing in elevated [CO2] used more water and that tree size, but not maximal water use, was negatively affected by elevated [O3] suggest that the long-term cumulative effects on stand structure may be more important than the expected primary stomatal closure responses to

  16. Influence of the Oil Phase and Topical Formulation on the Wound Healing Ability of a Birch Bark Dry Extract.

    Science.gov (United States)

    Steinbrenner, Isabel; Houdek, Pia; Pollok, Simone; Brandner, Johanna M; Daniels, Rolf

    2016-01-01

    Triterpenes from the outer bark of birch are known for various pharmacological effects including enhanced wound healing (WH). A birch bark dry extract (TE) obtained by accelerated solvent extraction showed the ability to form oleogels when it is suspended in oils. Consistency of the oleogels and the dissolved amount of triterpenes varies largely with the used oil. Here we wanted to know to what extent different oils and formulations (oleogel versus o/w emulsion) influence WH. Looking at the plain oils, medium-chain triglycerides (MCT) enhanced WH (ca. 1.4-fold), while e.g. castor oil (ca.0.3-fold) or light liquid paraffin (LLP; ca. 0.5-fold) significantly decreased WH. Concerning the respective oleogels, TE-MCT showed no improvement although the solubility of the TE was high. In contrast, the oleogel of sunflower oil which alone showed a slight tendency to impair WH, enhanced WH significantly (ca. 1.6-fold). These results can be explained by release experiments where the release rate of betulin, the main component of TE, from MCT oleogels was significantly lower than from sunflower oil oleogels. LLP impaired WH as plain oil and even though it released betulin comparable to sunflower oil it still results in an overall negative effect of the oleogel on WH. As a further formulation option also surfactant free o/w emulsions were prepared using MCT, sunflower oil and LLP as a nonpolar oil phase. Depending on the preparation method (suspension or oleogel method) the distribution of the TE varied markedly and affected also release kinetics. However, the released betulin was clearly below the values measured with the respective oleogels. Consequently, none of the emulsions showed a significantly positive effect on WH. In conclusion, our data show that the oil used as a vehicle influences wound healing not only by affecting the release of the extract, but also by having its own vehicle effect on wound healing. This is also of importance for other applications where drugs

  17. Experimental study comparing the behaviour of steel truss plates and birch plywood inserts in ridge joints on glued laminated rafters

    Directory of Open Access Journals (Sweden)

    López Gayarre, F.

    2009-08-01

    Full Text Available The present paper reports on an analysis of the mechanical performance of two flat joining systems used in roof members made of glued laminated timber.Six pairs of laminated timber rafters for a double-pitched roof with a 100x180-mm cross-section, a 6.00-m span and a height of 1.00 m were subjected to full-scale four-point bending. In three of the specimens the rafters were joined at the ridge with a birch plywood insert, while in the other three the connection was secured with a fitting consisting in a standard flat steel truss plate. The objective pursued was to evaluate the possibility of replacing the steel fittings with birch plywood inserts. The approach adopted to reach this objective was to compare the strength of the two joint pieces and the deformation generated in the overall structure during strength tests.The results proved to be highly satisfactory in terms of both the bearing capacity and the stiffness of the structures tested.El presente trabajo tiene por objeto llevar a cabo un análisis experimental del comportamiento mecánico de ciertos sistemas planos de unión para elementos estructurales de madera laminada empleados en la construcción de cubiertas.El estudio incluye los ensayos a escala real de seis din-teles a dos aguas de madera laminada, de 6 m de luz, 1 m de altura y una sección de 100 mm x 180 mm, sometidos a flexión en cuatro puntos. En tres dinteles el elemento de unión es una pieza de tablero contra-chapado de abedul, mientras que en los otros tres se ha utilizado un herraje de acero. La finalidad es valorar la posibilidad de sustituir los elementos de unión, realizados mediante herrajes, por otros constituidos por piezas de tablero contrachapado de abedul. Este objetivo se logra comparando el comportamiento resistente mostrado por ambos dispositivos de unión, y las deformaciones en cada caso de las estructuras completas.Los resultados resultaron muy satisfactorios tanto en la capacidad portante como en la

  18. Effect of radial directional dependences and rainwater influence on CVOC concentrations in tree core and birch sap samples taken for phytoscreening using HS-SPME-GC/MS.

    Science.gov (United States)

    Holm, Olaf; Rotard, Wolfgang

    2011-11-15

    Phytoscreening for chlorinated volatile organic compounds (CVOC) in tree core samples is influenced by many factors. For instance, greater fluctuations are observed for CVOC concentrations in samples taken around the trunk at a fixed height compared to samples taken directly next to each other. To avoid false negatives and inaccurate interpretation of the results, we investigated this radial directional dependence as well as the influence of rainwater on measured concentrations. CVOC analysis was performed by gas chromatography/mass spectrometry (GC/MS) following Solid-Phase-Microextraction (SPME). Phytoscreening was successfully carried out at three sites using this method. In addition, sap samples were taken from white birches during their budding period as a novel phytoscreening approach. Birch sap sampling is shown to be a suitable means of characterizing contaminant distribution within the soil subsurface. Radial directional dependence of CVOC concentrations varies by almost 80% for tree core samples and 50% for birch sap samples. Variations in concentrations measured around the trunk do not, however, provide information on the inflow direction of contaminated groundwater. The weather conditions were shown to have a greater influence so that CVOC concentrations measured from samples taken during colder, rainier weather were, on average, a factor of 100 lower than those taken during a warm and dry period. Nevertheless phytoscreening is adequate for CVOC characterization in the soil subsurface if the campaign is carried out during a dry weather period, the results then can be taken as being semiquantitative.

  19. The influence of weather conditions on the course of pollen seasons of alder (Alnus spp., hazel (Corylus spp. and birch (Betula spp. in Lublin (2001-2006

    Directory of Open Access Journals (Sweden)

    Agnieszka Dąbrowska

    2012-12-01

    Full Text Available The start and rate of florescence of Alnus, Corylus and Betula are dependent on meteorological conditions. In the present paper we have analysed the effect of mean, maximum and minimum temperature, relative air humidity and precipitation on the onset of the pollen season as well as on its length and annual count of pollen grains in alder, hazel and birch. The measurement of pollen fall was done by the gravimetric methods with the use of Durham sampler. Correlation coefficients were calculated between the determined characteristics of the pollen season and weather conditions. In the six-year research period 2001-2006 it was observed that low temperatures in January produced a delayed start of the pollen season in alder, hazel and birch. The beginning of flowering in these taxa was also influenced by thermal conditions prevailing directly before the season (ca. 10 days. The pollen season of the trees in question tended to be prolonged alongside with the increase in relative air humidity, but it was shortened due to higher temperatures. The volume of alder and hazel pollen release increased together with the rise in relative air humidity and precipitation. The annual counts of birch pollen increased along with rising temperature and decreasing relative air humidity and precipitation in the season.

  20. Responses of gas exchange and plant hydraulic conductance to water deficit in silver birch trees growing under increasing atmospheric humidity

    Science.gov (United States)

    Sellin, Arne; Kupper, Priit

    2013-04-01

    Climate change scenarios predict increase in air temperature by 3.5-5° C and precipitation by 5-30% in boreal and northern temperate regions of Europe by the end of the century. On the other hand, climate extremes including heat waves and droughts are projected to become more frequent and last longer across Europe over the 21st century. Increasing atmospheric humidity inevitably occurring with more frequent rainfall events reduce water fluxes through the vegetation, and have an effect on the structure of leaves and vascular tissues, plant hydraulic properties, biomass allocation, nutrient uptake and growth (Tullus et al. 2012). We investigated fast and long-term effects of water deficit on plant water status, gas exchange and hydraulic conductance on saplings of silver birch (Betula pendula) growing under artificially manipulated air humidity in an experimental forest ecosystem at the Free Air Humidity Manipulation site (http://www.lote.ut.ee/FAHM/in-english; Kupper et al. 2011). Fast-developing water deficit was imposed by letting cut sample branches to dehydrate in open-air conditions, long-term water deficit was generated by seasonal drought. The fast-imposed water deficit estimated by leaf (ΨL) or branch water status (ΨB) had highly significant (P

  1. Humus bacteria of Norway spruce stands: plant growth promoting properties and birch, red fescue and alder colonizing capacity.

    Science.gov (United States)

    Elo; Maunuksela; Salkinoja-Salonen; Smolander; Haahtela

    2000-02-01

    We studied the potential of the humus layer of the Norway spruce stands to supply beneficial rhizobacteria to birch (Betula pendula), alder (Alnus incana) and fescue grass (Festuca rubra), representatives of pioneer vegetation after clear-cutting of the coniferous forest. Axenically grown seedlings of these species were inoculated with the acid spruce humus, pH 3.7-5.3. Actinorhizal propagules, capable of nodulating alder, were present in high density (10(3) g(-1)) in humus of long-term limed plots, whereas plots with nitrogen fertilization contained almost none (

  2. Inhibition of snowshoe hare succinate dehydrogenase activity as a mechanism of deterrence for papyriferic acid in birch.

    Science.gov (United States)

    Forbey, Jennifer Sorensen; Pu, Xinzhu; Xu, Dong; Kielland, Knut; Bryant, John

    2011-12-01

    The plant secondary metabolite papyriferic acid (PA) deters browsing by snowshoe hares (Lepus americanus) on the juvenile developmental stage of the Alaska paper birch (Betula neoalaskana). However, the physiological mechanism that reduces browsing remains unknown. We used pharmacological assays and molecular modeling to test the hypothesis that inhibition of succinate dehydrogenase (SDH) is a mode of action (MOA) of toxicity of PA in snowshoe hares. We tested this hypothesis by measuring the effect of PA on the activity of SDH in liver mitochondria isolated from wild hares. In addition, we used molecular modeling to determine the specific binding site of PA on SDH. We found that PA inhibits SDH from hares by an uncompetitive mechanism in a dose-dependent manner. Molecular modeling suggests that inhibition of SDH is a result of binding of PA at the ubiquinone binding sites in complex II. Our results provide a MOA for toxicity that may be responsible for the concentration-dependent anti-feedant effects of PA. We propose that snowshoe hares reduce the dose-dependent toxic consequences of PA by relying on efflux transporters and metabolizing enzymes that lower systemic exposure to dietary PA.

  3. Evaluation of the mechanism of gelation of an oleogel based on a triterpene extract from the outer bark of birch.

    Science.gov (United States)

    Grysko, M; Daniels, R

    2013-07-01

    Oleogels are known for their high physical, chemical, and mechanical stability and good in vivo efficacy, which make them appropriate vehicles for dermal drug delivery and skin care for very dry skin. Modern formulation research focusses on well tolerated and sustainable formulation concepts. This paper deals with an innovative oleogel, which is based on a triterpene dry extract from the outer bark of birch (TE). In this formulation TE does not only act as an excipient but provides interesting pharmacological properties at the same time. The oleogel was formulated using solely Simmondsia Chinensis seed oil (jojoba oil) and TE. Fluorescence microscopy and confocal Raman microscopy showed that suspended TE particles arrange in a three-dimensional gel network. Infrared spectroscopy revealed that the formation of hydrogen bonds between TE particles is responsible for the self-assembly of TE in oil. Moreover, the influence of TE concentration and morphology of the TE particles on the viscoelasticity of the resulting oleogels was analyzed. Gel strength increased with TE concentration and was critical to the specific surface area of the TE particles.

  4. The Effects of Surface Roughness on Adhesion Strength of Coated Ash (Fraxinus excelsior L. and Birch (Betula L. Wood

    Directory of Open Access Journals (Sweden)

    Justina VITOSYTĖ

    2012-12-01

    Full Text Available For the evaluation of surface roughness impact on adhesion properties, the samples of dried ash (Fraxinus excelsior L. and birch (Betula L. wood were used. Before wood finishing, the surfaces of the samples were sanded. In order to get different surface roughness the abrasive material of P80, P120, P150, P180, P220 and P240 grit was used. The parameters of surface roughness Ra, Rz and Rmax were measured in three directions: along the wood grain, across the grain and in the angle of 45º. Comparison of the results showed the non-linear dependency of roughness parameters. Afterwards the wood surface was coated with three different acrylic-polyurethane coating systems (1 layer of varnish without primer, 1 layer of primer and 1 layer of varnish, and 1 layer of primer and 2 layers of varnish. The adhesion strength was assessed using the pull-off method. Also the nature of the fracture was evaluated. It was determined that the peculiarities of surface roughness, coating system type and wood species signally results the values of the adhesion strength.DOI: http://dx.doi.org/10.5755/j01.ms.18.4.3094

  5. Evaluation of the mechanism of gelation of an oleogel based on a triterpene extract from the outer bark of birch.

    Science.gov (United States)

    Grysko, M; Daniels, R

    2013-07-01

    Oleogels are known for their high physical, chemical, and mechanical stability and good in vivo efficacy, which make them appropriate vehicles for dermal drug delivery and skin care for very dry skin. Modern formulation research focusses on well tolerated and sustainable formulation concepts. This paper deals with an innovative oleogel, which is based on a triterpene dry extract from the outer bark of birch (TE). In this formulation TE does not only act as an excipient but provides interesting pharmacological properties at the same time. The oleogel was formulated using solely Simmondsia Chinensis seed oil (jojoba oil) and TE. Fluorescence microscopy and confocal Raman microscopy showed that suspended TE particles arrange in a three-dimensional gel network. Infrared spectroscopy revealed that the formation of hydrogen bonds between TE particles is responsible for the self-assembly of TE in oil. Moreover, the influence of TE concentration and morphology of the TE particles on the viscoelasticity of the resulting oleogels was analyzed. Gel strength increased with TE concentration and was critical to the specific surface area of the TE particles. PMID:23923639

  6. Kinetic modeling of multi-feed simultaneous saccharification and co-fermentation of pretreated birch to ethanol.

    Science.gov (United States)

    Wang, Ruifei; Koppram, Rakesh; Olsson, Lisbeth; Franzén, Carl Johan

    2014-11-01

    Fed-batch simultaneous saccharification and fermentation (SSF) is a feasible option for bioethanol production from lignocellulosic raw materials at high substrate concentrations. In this work, a segregated kinetic model was developed for simulation of fed-batch simultaneous saccharification and co-fermentation (SSCF) of steam-pretreated birch, using substrate, enzymes and cell feeds. The model takes into account the dynamics of the cellulase-cellulose system and the cell population during SSCF, and the effects of pre-cultivation of yeast cells on fermentation performance. The model was cross-validated against experiments using different feed schemes. It could predict fermentation performance and explain observed differences between measured total yeast cells and dividing cells very well. The reproducibility of the experiments and the cell viability were significantly better in fed-batch than in batch SSCF at 15% and 20% total WIS contents. The model can be used for simulation of fed-batch SSCF and optimization of feed profiles. PMID:25270046

  7. Research on stand structure of the white birch secondary forest in Saihanba%塞罕坝地区白桦次生林林分结构研究

    Institute of Scientific and Technical Information of China (English)

    杨晓勤; 田国恒; 宋新英

    2013-01-01

    The article takes the white birch secondary forest in Saihanba as the object of study , and mainly researches the diameter and the tree high distribution rule ,and carries on Weibull distribution and the normal distribution model fitting of the white birch's diameter and the tree high distribution using the ForStat statistics software and χ2 the examination to examine its distribution fitting effect ,finally demonstrating the white birch secondary forest diameter distribution as a whole to present the normal distribution rarely in Saihanba ,but the high distribution presents a cast distribution tendency .The white birch secondary forest diameter distribution simulation research shows a significance in its diameter Weibull distribution function difference ,a better fitting effect in the white birch forest diameter distribution .The tree high distribution of the white birch secondary forest simulation research reveals that there is a significant difference in both Weibull distribution function and normal distribution function of the white birch secondary forest tree high.%以塞罕坝地区白桦次生林为研究对象,主要对其直径、树高分布规律进行研究。并运用ForStat统计软件对白桦林分的直径、树高分布进行Weibull分布和正态分布模型拟合,采用χ2检验对其分布拟合效果进行检验。结果表明:塞罕坝地区白桦次生林直径分布总体上呈现正态分布,而树高分布呈现右偏的分布趋势;对其直径分布模拟的研究显示,其直径的Weibull分布函数差异达到显著性。

  8. Modelling of the spring phenological phases of the Silver birch Betula pendula and Bird cherry Padus racemosa in Baltic region

    Science.gov (United States)

    Kalvāns, Andis; Kalvāne, Gunta; Bitāne, Māra; Cepīte-Frišfelde, Daiga; Sīle, Tija; Seņņikovs, Juris

    2014-05-01

    The air temperature is the strongest driving factor of the plant development during spring time in moderate climate conditions. However other factors such as the air temperature during the dormancy period and light conditions can play a role as well. The full potential of the recent and historical phenological observation data can be utilised by modelling tools. We have calibrated seven phenological models described in scientific literature to calculate the likely dates leaf unfolding and start of flowering of the Silver birch Betula pendula and bird cherry Padus racemosa (Kalvāns at al, accepted). Phenological observations are derived from voluntary observation network for period 1960-2009 in Latvia. The number of used observations for each phase range from 149 to 172. Air temperature data measured in meteorological stations closest to the corresponding phenological observation sites are obtained from Latvian Environment, Geology and Meteorology Centre. We used 33 random data subsamples for model calibration to produce a range of model coefficients enabling the estimation of the phenological model uncertainty. It is found that the best reproduction of the observational data are obtained using a simple linear degree day model considering daily minimum and maximum temperature and more complex sigmoidal model honouring the need for low temperatures for dormancy release (UniChill, Chuine, 2000). The median calibration base temperature in the degree day model for the silver birch leaf unfolding is 5.6°C and for start of the flowering 6.7°C; for the bird cherry the corresponding base temperatures are 3.2°C and 3.4°C. The calibrated models and air temperature archive data derived from the Danish Meteorological Institute is used to simulate the respective phase onset in the Estonia, Latvia and Lithuania in 2009. Significant regional differences between modelled phase onset times are observed. There is a wide regional variation of the model uncertainty as well

  9. Pimecrolimus Is a Potent Inhibitor of Allergic Reactions to Hymenopteran Venom Extracts and Birch Pollen Allergen In Vitro.

    Science.gov (United States)

    Heneberg, Petr; Riegerová, Kamila; Kučera, Petr

    2015-01-01

    Pimecrolimus (Elidel, SDZ ASM 981) is an anti-inflammatory and immunomodulatory 33-epichloro-derivative of macrolactam ascomycin, with low potential for affecting systemic immune responses compared with other calcineurin inhibitors, cyclosporin A and tacrolimus. Despite numerous studies focused on the mechanism of pimecrolimus action on mast cells, only the single report has addressed pimecrolimus effects on other typical FcεRI-expressing cells, the basophils. Patients allergic to birch pollen (n = 20), hymenopteran venoms (n = 23) and 10 non-allergic volunteers were examined. Primary human basophils pre-treated or not with 0.5-50 μMol pimecrolimus were exposed to various concentrations of recombinant Bet v 1a allergen, bee or wasp venom extracts and anti-IgE for 20 min, and then examined for the expression of CD45, CD193, CD203c, CD63 and CD164 using flow cytometry. The externalization of basophil activation markers (CD63 and CD164) was equally inhibited through pimecrolimus in cells activated by recombinant pollen allergen, hymenopteran venom extracts and anti-IgE. Although the individual response rate was subject to strong variation, importantly, pre-treatment with pimecrolimus lowered the number of activated basophils in response to any of the stimuli in the basophils from all patients. The inhibition was concentration-dependent; approximately half of the basophils were inhibited in the presence of 2.5 mMol pimecrolimus. Pimecrolimus is a valuable new tool for the inhibition of hyper-reactive basophils in patients with pollen allergy and a history of anaphylactic reactions to bee or wasp venoms. Further research should address short-term use of pimecrolimus in vivo in a wide spectrum of allergic diseases. PMID:26562153

  10. Pimecrolimus Is a Potent Inhibitor of Allergic Reactions to Hymenopteran Venom Extracts and Birch Pollen Allergen In Vitro.

    Directory of Open Access Journals (Sweden)

    Petr Heneberg

    Full Text Available Pimecrolimus (Elidel, SDZ ASM 981 is an anti-inflammatory and immunomodulatory 33-epichloro-derivative of macrolactam ascomycin, with low potential for affecting systemic immune responses compared with other calcineurin inhibitors, cyclosporin A and tacrolimus. Despite numerous studies focused on the mechanism of pimecrolimus action on mast cells, only the single report has addressed pimecrolimus effects on other typical FcεRI-expressing cells, the basophils. Patients allergic to birch pollen (n = 20, hymenopteran venoms (n = 23 and 10 non-allergic volunteers were examined. Primary human basophils pre-treated or not with 0.5-50 μMol pimecrolimus were exposed to various concentrations of recombinant Bet v 1a allergen, bee or wasp venom extracts and anti-IgE for 20 min, and then examined for the expression of CD45, CD193, CD203c, CD63 and CD164 using flow cytometry. The externalization of basophil activation markers (CD63 and CD164 was equally inhibited through pimecrolimus in cells activated by recombinant pollen allergen, hymenopteran venom extracts and anti-IgE. Although the individual response rate was subject to strong variation, importantly, pre-treatment with pimecrolimus lowered the number of activated basophils in response to any of the stimuli in the basophils from all patients. The inhibition was concentration-dependent; approximately half of the basophils were inhibited in the presence of 2.5 mMol pimecrolimus. Pimecrolimus is a valuable new tool for the inhibition of hyper-reactive basophils in patients with pollen allergy and a history of anaphylactic reactions to bee or wasp venoms. Further research should address short-term use of pimecrolimus in vivo in a wide spectrum of allergic diseases.

  11. Posttranslational modification of Birch and Ragweed allergen proteins by common gas phase pollutants, NO2 and O3

    Science.gov (United States)

    Mahmood, M. A.; Pope, F.; Bloss, W.

    2015-12-01

    The global incidence of hay fever has been rising for decades, however, the underlying reasons behind this rise remain unclear. It is hypothesized that exposure of pollen to common gas phase pollutants, such as nitrogen dioxide (NO2) and ozone (O3), increases the allergenicity of the pollen and thus increases hay fever incidence. Since atmospheric pollutants tend to have greater concentrations within urban areas (in particular NO2) the hypothesis suggests that greater allergenicity should occur in urban areas. Indeed, several studies do suggest higher hay fever incidence within urban areas compared to rural areas. Previous published work suggests a link between increased allergies with changes in the chemical composition of the pollen protein via posttranslational modification of the protein. This study investigates the posttranslational modification of two highly allergenic pollen species (Birch and Ragweed) that are common in Europe. Within the laboratory, we expose pollen grains to atmospherically relevant exposures of gas phase NO2, O3 and other common gas phase oxidants under a range of environmentally relevant conditions. The effects of the environmentally relevant exposures on the biochemistry of the pollen grains were probed using a proteomic approach (liquid chromatography coupled ultra-high resolution spectrometer). Our findings indicate the interaction between gas phase pollutants and pollen cause protein specific modifications; in particular, nitration occurs upon tyrosine residues and nitrosylation on cysteine residues. Possibly, these modifications may affect the immune response of the pollen protein, which may suggest a possible reason for increased allergies in reaction to such biologically altered protein. The laboratory-derived results will be supported with a time series analysis of asthma incidence rates for the London area, which take into account the pollen count, and pollutant concentrations. The implications of the results will be discussed

  12. Daily dynamics of leaf and soil-to-branch hydraulic conductance in silver birch (Betula pendula) measured in situ.

    Science.gov (United States)

    Õunapuu, Eele; Sellin, Arne

    2013-07-01

    Daily dynamics of leaf (K(L)) and soil-to-branch hydraulic conductance (KS-B) was investigated in silver birch (Betula pendula Roth.) using evaporative flux method in situ: water potential drop was measured with a pressure chamber and evaporative flux was estimated as sap flux density measured with sap flow gauges. Canopy position had a significant (P effect on both K(L) and K(S-B). Upper-canopy leaves exhibited 1.7 and soil-to-branch pathway 2.3 times higher hydraulic efficiency than those for lower-canopy. K(L) varied significantly with time of day: K(L) for both upper- and lower-canopy leaves was lowest in the morning and rose gradually achieving maximal values in late afternoon (4.75 and 3.38 mmol m⁻² s⁻¹ MPa⁻¹, respectively). Relevant environmental factors affecting K(L) were photosynthetic photon flux density (Q(P)), air relative humidity (RH) and air temperature (T(A)). K(S-B) started rising in the morning and reached maximum in the lower canopy (1.44 mmol m⁻² s⁻¹ MPa⁻¹) at 1300 h and in the upper canopy (2.52 mmol m⁻² s⁻¹ MPa⁻¹) at 1500 h, decreasing afterwards. Environmental factors controlling K(S-B) were Ψ(S) and Q(P). The diurnal patterns of K(L) reflect a combination of environmental factors and endogenous rhythms. The temporal pattern of K(S-B) refers to daily up- and down-regulation of hydraulic conductance of water transport pathway from soil-root interface to leaves with respect to changing irradiance.

  13. Impact of light quality on leaf and shoot hydraulic properties: a case study in silver birch (Betula pendula).

    Science.gov (United States)

    Sellin, Arne; Sack, Lawren; Õunapuu, Eele; Karusion, Annika

    2011-07-01

    Responses of leaf and shoot hydraulic conductance to light quality were examined on shoots of silver birch (Betula pendula), cut from lower ('shade position') and upper thirds of the crowns ('sun position') of trees growing in a natural temperate forest stand. Hydraulic conductances of leaf blades (K(lb) ), petioles (K(P) ) and branches (i.e. leafless stem; K(B) ) were determined using a high pressure flow meter in steady state mode. The shoots were exposed to photosynthetic photon flux density of 200-250 µmol m⁻² s⁻¹ using white, blue or red light. K(lb) depended significantly on both light quality and canopy position (Peffect on K(P) . The highest values of K(lb) were recorded under the blue light (3.63 and 3.13×10⁻⁴ kg m⁻² MPa⁻¹ s⁻¹ for the sun and shade leaves, respectively), intermediate values under white light (3.37 and 2.46×10⁻⁴ kg m⁻² MPa⁻¹ s⁻¹ , respectively) and lowest values under red light (2.83 and 2.02×10⁻⁴ kg m⁻² MPa⁻¹ s⁻¹, respectively). Light quality has an important impact on leaf hydraulic properties, independently of light intensity or of total light energy, and the specific light receptors involved in this response require identification. Given that natural canopy shade depletes blue and red light, K(lb) may be decreased both by reduced fluence and shifts in light spectra, indicating the need for studies of the natural heterogeneity of K(lb) within and under canopies, and its impacts on gas exchange.

  14. Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils.

    Science.gov (United States)

    Hagner, Marleena; Hallman, Sanna; Jauhiainen, Lauri; Kemppainen, Riitta; Rämö, Sari; Tiilikkala, Kari; Setälä, Heikki

    2015-12-01

    Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the leaching of (i) glyphosate, (ii) its primary degradation product AMPA and (iii) phosphorus from the soil. The biochar types used were produced at three different temperatures: 300 °C (BC300), 375 °C (BC375) and 475 °C (BC475). Compared to the control treatment without biochar, the leaching of glyphosate was reduced by 81%, 74% and 58% in BC300, BC375 and BC475 treated soils, respectively. The respective values for AMPA were 46%, 39% and 23%. Biochar had no significant effect on the retention of water-soluble phosphorus in the soil. Our results corroborate earlier findings on pesticides, suggesting that biochar amendment to the soil is a promising way to reduce also the leaching of glyphosate. Importantly, the ability of biochar to adsorb agro-chemicals depends on the temperature at which feedstock is pyrolysed. PMID:26342266

  15. Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils.

    Science.gov (United States)

    Hagner, Marleena; Hallman, Sanna; Jauhiainen, Lauri; Kemppainen, Riitta; Rämö, Sari; Tiilikkala, Kari; Setälä, Heikki

    2015-12-01

    Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the leaching of (i) glyphosate, (ii) its primary degradation product AMPA and (iii) phosphorus from the soil. The biochar types used were produced at three different temperatures: 300 °C (BC300), 375 °C (BC375) and 475 °C (BC475). Compared to the control treatment without biochar, the leaching of glyphosate was reduced by 81%, 74% and 58% in BC300, BC375 and BC475 treated soils, respectively. The respective values for AMPA were 46%, 39% and 23%. Biochar had no significant effect on the retention of water-soluble phosphorus in the soil. Our results corroborate earlier findings on pesticides, suggesting that biochar amendment to the soil is a promising way to reduce also the leaching of glyphosate. Importantly, the ability of biochar to adsorb agro-chemicals depends on the temperature at which feedstock is pyrolysed.

  16. Oocyst-Derived Extract of Toxoplasma Gondii Serves as Potent Immunomodulator in a Mouse Model of Birch Pollen Allergy.

    Directory of Open Access Journals (Sweden)

    Angelika Wagner

    Full Text Available Previously, we have shown that oral infection with Toxoplasma gondii oocysts prevented type I allergy in mice. Here we investigated whether the application of a T. gondii oocyst lysate antigen (OLA could also reduce allergy development. BALB/c mice were immunised twice with OLA followed by sensitisation with the major birch pollen (BP allergen Bet v 1 and an aerosol challenge with BP extract.First, we tested OLA in vitro. Stimulation of splenocytes and bone marrow-derived dendritic cells (BMDC with OLA led to the production of pro-inflammatory and regulatory cytokines such as IL-6, IFN-γ and IL-10. Moreover, BMDC exposed to OLA upregulated the maturation markers CD40, CD80, CD86, and MHCII. Furthermore, OLA was recognised by TLR2-transfected human embryonic kidney cells.Immunisation of mice with OLA induced high levels of Toxoplasma-specific IgG antibodies in sera along with increased production of IFN-γ and IL-10 in Toxoplasma-antigen restimulated splenocytes. OLA reduced allergic airway inflammation as manifested by significant reduction of eosinophils in bronchoalveolar fluids, decreased cellular infiltrates and mucus production in the lungs. Accordingly, Bet v 1-specific IgE was decreased in OLA-pretreated mice. The reduced allergic immune responses were accompanied by increased numbers of CD4+CD25highFoxp3+ regulatory T cells in spleens as well as by increased numbers of granulocytic myeloid-derived suppressor cells in lungs when compared to sensitised controls suggesting that these two cell populations might be involved in the suppression of the allergic immune responses.Our data demonstrate that pretreatment with the oocyst extract can exert anti-allergic effects comparable to T. gondii infection. Thus, the immunomodulatory properties of the parasite extract indicate that this extract and in the future defined molecules thereof might serve as immunomodulatory adjuvants in allergy treatment and prophylaxis.

  17. Seasonal dynamics of saproxylic beetles (Coleoptera occurring in decaying birch (Betula spp. wood in the Kampinos National Park

    Directory of Open Access Journals (Sweden)

    Sawoniewicz Michał

    2015-09-01

    Full Text Available The aim of the study was to identify the seasonal changes in the number of saproxylic beetles connected with birch in the Kampinos National Park. The research was conducted for 12 consecutive months in research areas representing 10 different site types. The beetles were collected from wood using photoeclectors. The largest number of species was collected in April and the lowest in January. An increase in number occurred during spring and summer months for species associated only with rotting wood, fructifications of tree fungi, the subcortical environment and hollows. In the same period the number of species not associated or potentially associated with decaying trees and wood decreased. During winter months, the differences in the number of trapped specimens were the smallest. The proportion of zoophagous species amongst the collected specimen increased in autumn and winter. The share of saprophagous species was the highest during the summer-autumn period and the share of mycetophages (jointly with myxomycophages was the highest during spring and summer. We distinguished two separate groups of Coleoptera with the first one (‘summer group’ including species trapped during late-spring and summer months, while the second one (‘winter group’ includes species found in autumn, winter and early-spring months. In the ‘summer group’, an average of 55.8 species was trapped each month with 331.2 specimen of Coleoptera, while in the ʻwinter group’ an average of 56.1 species with 228.4 Coleoptera specimen were caught.

  18. Leaf and canopy conductance in aspen and aspen-birch forests under free-air enrichment of carbon dioxide and ozone.

    Science.gov (United States)

    Uddling, Johan; Teclaw, Ronald M; Pregitzer, Kurt S; Ellsworth, David S

    2009-11-01

    Increasing concentrations of atmospheric carbon dioxide (CO2) and tropospheric ozone (O3) have the potential to affect tree physiology and structure, and hence forest feedbacks on climate. Here, we investigated how elevated concentrations of CO2 (+45%) and O3 (+35%), alone and in combination, affected conductance for mass transfer at the leaf and canopy levels in pure aspen (Populus tremuloides Michx.) and in mixed aspen and birch (Betula papyrifera Marsh.) forests in the free-air CO2-O3 enrichment experiment near Rhinelander, Wisconsin (Aspen FACE). The study was conducted during two growing seasons, when steady-state leaf area index (L) had been reached after > 6 years of exposure to CO2- and O3-enrichment treatments. Canopy conductance (g(c)) was estimated from stand sap flux, while leaf-level conductance of sun leaves in the upper canopy was derived by three different and independent methods: sap flux and L in combination with vertical canopy modelling, leaf 13C discrimination methodology in combination with photosynthesis modelling and leaf-level gas exchange. Regardless of the method used, the mean values of leaf-level conductance were higher in trees growing under elevated CO2 and/or O3 than in trees growing in control plots, causing a CO2 x O3 interaction that was statistically significant (P aspen and mixed aspen-birch communities. These results demonstrate that short-term primary stomatal closure responses to elevated CO2 and O3 were completely offset by long-term cumulative effects of these trace gases on tree and stand structure in determining canopy- and leaf-level conductance in pure aspen and mixed aspen-birch forests. Our results, together with the findings from other long-term FACE experiments with trees, suggest that model assumptions of large reductions in stomatal conductance under rising atmospheric CO2 are very uncertain for forests.

  19. Interactive effects of elevated ozone and temperature on carbon allocation of silver birch (Betula pendula) genotypes in an open-air field exposure.

    Science.gov (United States)

    Kasurinen, Anne; Biasi, Christina; Holopainen, Toini; Rousi, Matti; Mäenpää, Maarit; Oksanen, Elina

    2012-06-01

    In the present experiment, the single and combined effects of elevated temperature and ozone (O(3)) on four silver birch genotypes (gt12, gt14, gt15 and gt25) were studied in an open-air field exposure design. Above- and below-ground biomass accumulation, stem growth and soil respiration were measured in 2008. In addition, a (13)C-labelling experiment was conducted with gt15 trees. After the second exposure season, elevated temperature increased silver birch above- and below-ground growth and soil respiration rates. However, some of these variables showed that the temperature effect was modified by tree genotype and prevailing O(3) level. For instance, in gt14 soil respiration was increased in elevated temperature alone (T) and in elevated O(3) and elevated temperature in combination (O(3) + T) treatments, but in other genotypes O(3) either partly (gt12) or totally nullified (gt25) temperature effects on soil respiration, or acted synergistically with temperature (gt15). Before leaf abscission, all genotypes had the largest leaf biomass in T and O(3) + T treatments, whereas at the end of the season temperature effects on leaf biomass depended on the prevailing O(3) level. Temperature increase thus delayed and O(3) accelerated leaf senescence, and in combination treatment O(3) reduced the temperature effect. Photosynthetic : non-photosynthetic tissue ratios (P : nP ratios) showed that elevated temperature increased foliage biomass relative to woody mass, particularly in gt14 and gt12, whereas O(3) and O(3) + T decreased it most clearly in gt25. O(3)-caused stem growth reductions were clearest in the fastest-growing gt14 and gt25, whereas mycorrhizal root growth and sporocarp production increased under O(3) in all genotypes. A labelling experiment showed that temperature increased tree total biomass and hence (13)C fixation in the foliage and roots and also label return was highest under elevated temperature. Ozone seemed to change tree (13)C allocation, as it

  20. 白桦树皮提取物的降血脂作用研究%On Hypolipidemic Effects of White Birch Bark Extract

    Institute of Scientific and Technical Information of China (English)

    左红香; 郑光浩

    2012-01-01

    Objective To study hypolipidemic effects of white birch bark extract. Method The white birch bark extract (BH) at the dose of 300 mg/kg was given to mice in high-dose group,200 mg/kg in middle-dose group and 100 mg/kg in low-dose group, and Zhinbitieose at the dose of 300 mg/kg in the positive control group orally for 7 days for the prophylaxis of lipidemic disorders. At 2h after the final administration,75% egg yolk emulsion was intraperitoneally given to the mice in all groups except for the normal group to establish the mouse model of hyperlipidemia. Effects of BH at the different doses on lipid levels in blood in mice were measured at 12h after the modeling. Results The white birch bark extract could significantly reduce serum TC, TG and LDL-C contents, and significantly elevate HDL-C level. Conclusion The white birch bark extract can produce significantly hypolipidemic effect on mice.%目的研究白桦树皮提取物(BH)的降血脂作用.方法分正常组、模型组、BH给药组:高(300mg/kg)、中(200mg/kg)、低(100mg/kg)剂量和阳性对照组:脂必妥(300mg/kg).预防给药7d,末次给药2h后,腹腔注射75%蛋黄乳液制作小鼠高脂血症模型,造模12h后测定不同剂量的BH对小鼠血脂水平的影响.结果白桦树皮提取物能够显著降低小鼠血清中TC,TG,LDL-C浓度,显著升高HDL-C.结论白桦树皮提取物具有明显的降血脂作用.

  1. Recycling of wood- and peat-ash. A successful way to establish full plant cover and dense birch stand on a cut-away peatland

    Energy Technology Data Exchange (ETDEWEB)

    Huotari, N.

    2012-07-01

    Mechanical harvesting of peat changes the original mire ecosystem completely, and without active measures these areas may remain non-vegetated even for decades. Afforestation is one of the most popular after-use options for cut-away peatlands in Finland since it has both economic and aesthetic values. Recycling of wood-ash as a fertilizer has been studied extensively in peatlands drained for forestry. Wood-ash is reported to promote tree growth in these areas without any significant negative impact to the environment and could, therefore, be a suitable option also on cut-away peatlands. However, the environmental effects of ash-fertilization on cut-away areas and on ground vegetation are not fully understood. The impact of wood- and peat-ash application on the early establishment of ground vegetation and downy birch (Betula pubescens) seedlings and on post-fertilization element concentrations in plants and peat substrate were studied in a cut-away peatland. Six treatments of wood-ash, peat-ash, biotite or Forest PK-fertilizer were replicated in three blocks in different mixtures and quantities corresponding to 50 kg ha-1 of phosphorus. All the fertilizers accelerated the revegetation of the bare peat surface significantly, whereas the establishment of plants in the unfertilized area was non-existent even several years after the peat harvesting had ceased. The most striking difference between the wood- and peat-ash-fertilizers and the commercial Forest PK-fertilizer was the extensive coverage of fire-loving moss species in all the areas where ash was spread. Wood- and peat-ash application also accelerated the germination and early establishment of downy birch seedlings more efficiently than the PK-fertilizer. Ground vegetation proved to be highly important in increasing the early biomass production and carbon sequestration on ash-fertilized cut-away peatland. In addition, the below-ground biomass was equal to the above-ground biomass, or even greater. Both wood- and

  2. 白桦和落叶松苗木对其纯林土壤养分的生物检测%Soil nutrient status of pure birch and larch plantations based on their seedlings bioassay.

    Institute of Scientific and Technical Information of China (English)

    刘忠玲; 王庆成; 孙欣欣

    2011-01-01

    利用35年生白桦、落叶松纯林土壤分别栽植白桦、落叶松1年生苗木,通过对苗木生长、生物量、叶片养分及土壤养分变化的研究,对两种土壤的肥力进行评价,探讨白桦、落叶松混交林种间互作机制.结果表明:白桦纯林土壤全氮、碱解氮含量显著高于落叶松纯林土壤(P<0.05),落叶松纯林土壤全磷、全钾、速效磷含量显著高于白桦纯林土壤(P<0.05).盆栽第1年,白桦纯林土壤上的白桦苗木苗高、地径和生物量分别比在落叶松纯林土壤上增加69%、52%和65%( P<0.05),落叶松苗木分别增加12%、8%和37%(P>0.05).以白桦纯林土壤为基质时,白桦、落叶松苗木叶片氮浓度高于落叶松纯林土壤,而磷浓度低于落叶松纯林土壤.白桦凋落量大且分解速度快,落叶松对土壤磷具有活化作用,导致白桦纯林土壤氮素有效性较高,落叶松纯林土壤有效磷含量较高.推测两树种混交时,土壤氮、磷的互补作用可能对林分产量产生有益的作用.%One-year-old birch (Betula platyphylla) and larch ( Larix olgensis) seedlings were respectively planted in pots with the soils taken from 35-year-old pure birch and larch plantations, and the seedlings growth, biomass increment, foliar nutrient content, and soil nutrient status were monitored, aimed to evaluate the fertility levels of the two soils and the possible interspecific interaction in mixed larch-birch forest. Birch soil had significantly higher contents of total N and available N than larch soil, while larch soil had significantly higher contents of total P, available P, and total K than birch soil ( P<0.05 ). In the first growth season, the height and collar diameter growth and the biomass accumulation of birch seedlings growing on birch soil were 69% , 52% , and 65% (P<0. 05) higher than those growing on larch soil, and the larch seedlings also had 12% , 8% , and 37% gains of the indices, respectively. The foliar N

  3. Protein-lipid composition of silver birch (Betula verrucosa pollen and its antioxidant activity depending on habitat

    Directory of Open Access Journals (Sweden)

    T. Shevtsova

    2013-12-01

    Full Text Available Pollen has various effects on the human body. In order to study and compare the biological activity of the mature pollen grains of Betula verrucosa Ehrh. we investigated the protein-lipid composition and total antioxidant activity (TAA of 10 samples from different habitats in the territory of Ukraine and the Slovak Republic. The collection sites are near highways and apartment blocks, as well as a nature reserve, forest and botanical garden. The protein content was determined by the Kjeldahl method. A chromatographic analysis of fatty acids from lipids was performed using a “Cvet 500” gas chromatograph, equipped with a flame-ionization detector in the isothermal mode. The bioactivity of aqueous, ethanol and methanol extracts of pollen grains was evaluated by the DPPH free radical scavenging method (2,2-diphenyl-1-picrylhydrazyl by means spectrophotometry in vitro. The protein content of the pollen of B. verrucosa ranged from 17.9% to 25.6%, depending on the habitat. Unsaturated fatty acids were found in higher amounts than saturated fatty acids. The profile of fatty acids indicates a higher content of palmitic (33.9%, oleic (29.5% and linoleic (27.8% acids and a low content of arachidonic (0.4% and pentadecanoic (0.8% acids. We also established that silver birch pollen is characterized by high antioxidant activity. The measured value of TAA for aqueous pollen extracts was within 74.8–85.5%. For the ethanol extracts it was quantified within 60.3–95.0% and for the methanol extracts – 46.1–92.6%. The Tukey test was used to determine the differences between the means at a level of P < 0.05. A strong correlation coefficient (0.70 was defined between the protein content and the TAA of aqueous extracts. In general, the Ukrainian and Slovak samples of pollen differ in the fatty acid composition of lipids and aqueous and ethanol TAA extracts. Pollen of B. verrucosa should be used for diagnostic, therapeutic and prophylactic purposes as close

  4. Lack of Correlation between Ammonium Accumulation and Survival of Transgenic Birch Plants with Pine Cytosolic Glutamine Synthetase Gene after “Basta” Herbicide Treatment

    Directory of Open Access Journals (Sweden)

    Vadim Lebedev

    2015-01-01

    Full Text Available Transformation of plants with genes encoding a glutamine synthetase (GS, a key nitrogen metabolism enzyme, is usually used to increase productivity. However, overexpression of these genes may increase resistance to phosphinothricin (PPT that irreversibly inhibits GS causing ammonium accumulation in plant tissues. Transgenic plants of two birch (Betula pubescens genotypes expressing a pine cytosolic GS gene were used for studying the PPT effect on trees. Two control and 8 transgenic lines were treated with herbicide “Basta” at dose equivalent to 2.5 and 5 Lha−1. Necrosis and abscission of leaves occurred irrespective of a transgenic status or the treatment dose. Ammonium content in leaf tissue in 3 days after the 5 Lha−1 treatment was substantially increased in all plants, 3.2–16.0 times depending on line. After the 2.5 Lha−1 treatment, ammonium content in three transgenic lines was not different from that in control variant sprayed with water. The herbicide treatment caused more prominent desiccation in the bp3f1 genotype nontransgenic plants as compared to transgenic plants, but not in the bp4a genotype. Lack of correlation between ammonium levels and survival of transgenic plants suggests that ammonium toxicity is not a main reason for the birch plant death after the PPT treatment.

  5. Stomatal uptake of O3 in aspen and aspen-birch forests under free-air CO2 and O3 enrichment.

    Science.gov (United States)

    Uddling, Johan; Hogg, Alan J; Teclaw, Ronald M; Carroll, Mary Anne; Ellsworth, David S

    2010-06-01

    Rising atmospheric carbon dioxide (CO2) may alleviate the toxicological impacts of concurrently rising tropospheric ozone (O3) during the present century if higher CO2 is accompanied by lower stomatal conductance (gs), as assumed by many models. We investigated how elevated concentrations of CO2 and O3, alone and in combination, affected the accumulated stomatal flux of O3 (AFst) by canopies and sun leaves in closed aspen and aspen-birch forests in the free-air CO2-O3 enrichment experiment near Rhinelander, Wisconsin. Stomatal conductance for O3 was derived from sap flux data and AFst was estimated either neglecting or accounting for the potential influence of non-stomatal leaf surface O3 deposition. Leaf-level AFst (AFst(l)) was not reduced by elevated CO2. Instead, there was a significant CO2 x O(3) interaction on AFst(l), as a consequence of lower values of gs in control plots and the combination treatment than in the two single-gas treatments. In addition, aspen leaves had higher AFst(l) than birch leaves, and estimates of AFst(l) were not very sensitive to non-stomatal leaf surface O3 deposition. Our results suggest that model projections of large CO2-induced reductions in gs alleviating the adverse effect of rising tropospheric O3 may not be reasonable for northern hardwood forests.

  6. The effect of u.v.-B radiation on u.v.-absorbing secondary metabolites in birch seedlings grown under simulated forest soil conditions

    International Nuclear Information System (INIS)

    Birch (Betula pendula Roth) seedlings were grown under enhanced u.v.-B radiation and simulated forest-soil conditions, after which individual secondary metabolites were determined in the leaves. It was found that not all of the u.v.-absorbing secondary metabolites of the seedlings responded to supplementary u.v.-B radiation. Under increased u.v.-B radiation, significant increases in concentration were observed only for the major flavonoid, quercitrin, the minor fiavonoid, myricetin-3-galactoside, and for chlorogenic acid. On the other hand, 3,4′dihydroxypropiophenone-3-β-D-glucopyranoside decreased under u.v.-B irradiation. The concentration of phenolic compounds in the leaves changed during the growing season (between two harvests) but this change was not related to u.v.-B enhancement. A low availability of mineral nutrients did not impair the capacity of the seedlings to accumulate u.v.-protecting phenolic compounds under increased u.v.-B radiation. The growth conditions used might have affected the intracellular concentrations of secondary metabolites, and thus furnished the birch seedlings with an increased tolerance of u.v.-B radiation. These findings point to the significance of certain phenolic components in the protection of deciduous trees against u.v.-B radiation. (author)

  7. Gene expression responses of paper birch (Betula papyrifera) to elevated CO{sub 2} and O{sub 3} during leaf maturation and senescence

    Energy Technology Data Exchange (ETDEWEB)

    Kontunen-Soppela, Sari, E-mail: sari.kontunen-soppela@joensuu.f [Finnish Forest Research Institute, Suonenjoki Unit, Juntintie 154, FI-77600 Suonenjoki (Finland); University of Joensuu, Faculty of Biosciences, FI-80101 Joensuu (Finland); Parviainen, Juha [University of Kuopio, Department of Environmental Sciences, FI-70211 Kuopio (Finland); Ruhanen, Hanna [Finnish Forest Research Institute, Suonenjoki Unit, Juntintie 154, FI-77600 Suonenjoki (Finland); Brosche, Mikael [University of Helsinki, Faculty of Biosciences, Department of Biological and Environmental Sciences, FI-00014 Helsinki (Finland); Keinaenen, Markku [University of Joensuu, Faculty of Biosciences, FI-80101 Joensuu (Finland); Thakur, Ramesh C. [School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931 (United States); Kolehmainen, Mikko [University of Kuopio, Department of Environmental Sciences, FI-70211 Kuopio (Finland); Kangasjaervi, Jaakko [University of Helsinki, Faculty of Biosciences, Department of Biological and Environmental Sciences, FI-00014 Helsinki (Finland); Oksanen, Elina [University of Joensuu, Faculty of Biosciences, FI-80101 Joensuu (Finland); Karnosky, David F. [School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931 (United States); Vapaavuori, Elina [Finnish Forest Research Institute, Suonenjoki Unit, Juntintie 154, FI-77600 Suonenjoki (Finland)

    2010-04-15

    Gene expression responses of paper birch (Betula papyrifera) leaves to elevated concentrations of CO{sub 2} and O{sub 3} were studied with microarray analyses from three time points during the summer of 2004 at Aspen FACE. Microarray data were analyzed with clustering techniques, self-organizing maps, K-means clustering and Sammon's mappings, to detect similar gene expression patterns within sampling times and treatments. Most of the alterations in gene expression were caused by O{sub 3}, alone or in combination with CO{sub 2}. O{sub 3} induced defensive reactions to oxidative stress and earlier leaf senescence, seen as decreased expression of photosynthesis- and carbon fixation-related genes, and increased expression of senescence-associated genes. The effects of elevated CO{sub 2} reflected surplus of carbon that was directed to synthesis of secondary compounds. The combined CO{sub 2} + O{sub 3} treatment resulted in differential gene expression than with individual gas treatments or in changes similar to O{sub 3} treatment, indicating that CO{sub 2} cannot totally alleviate the harmful effects of O{sub 3}. - Clustering analysis of birch leaf gene expression data reveals differential responses to O{sub 3} and CO{sub 2}.

  8. Phenogenetic response of silver birch populations and half-sib families to elevated ozone and ultraviolet-B radiation at juvenile age

    International Nuclear Information System (INIS)

    Phenogenetic response of silver birch populations and half-sib families to separate and combined elevated ozone (O3) concentrations and ultraviolet-B (UV-B) radiation dozes was studied at juvenile age in the climatic chambers. Significant population and family effects were found for seedling height, lamina width, and leaf damage. The exposure to UV-B radiation decreased genetic variation at the stage of seed germination. Complex exposure to UV-B and O3 caused an increase of genetic variation at the stage of intensive seedling growth: seedling height genetic variation in separate treatments increased from 23.7-38.6 to 33.7-65.7%, the increase for lamina width was from 10.2-13.9 to 13.6-31.8%. Different populations and families demonstrated differing response to elevated complex UV-B and O3 exposure. Changes of genetic intra-population variation were population-specific. Such changes in genetic variation under the impact of stressors can alter adaptation, stability, and competitive ability of regenerating populations in a hardly predictive way. - Exposure to elevated UV-B and O3 alters genetic variation of traits in progenies of silver birch populations

  9. 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…

  10. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe;

    2003-01-01

    Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch...

  11. Responses of fungal root colonization, plant cover and leaf nutrients to long-term exposure to elevated atmospheric CO2 and warming in a subarctic birch forest understory

    DEFF Research Database (Denmark)

    Olsrud, Maria; Carlsson, Bengt Å.; Svensson, Brita M.;

    2010-01-01

    Responses of the mycorrhizal fungal community in terrestrial ecosystems to global change factors are not well understood. However, virtually all land plants form symbiotic associations with mycorrhizal fungi, with approximately 20% of the plants' net primary production transported down...... by mycorrhizal and other root-associated fungi to global change factors of all the fungal types studied could have broad implications for plant community structure and biogeochemistry of subarctic ecosystems....... to the fungal symbionts. In this study, we investigated how ericoid mycorrhiza (ErM), fine endophytes (FE) and dark septate endophytes (DSE) in roots responded to elevated atmospheric CO2 concentrations and warming in the dwarf shrub understory of a birch forest in the subarctic region of northern Sweden...

  12. Air pollution effects on the percentage of stomata in the leaves of tested species of horse chestnut and birch in Banja Luka conditions

    Directory of Open Access Journals (Sweden)

    Oljača Rodoljub

    2008-01-01

    Full Text Available The aim of this paper is the determination of air pollution influence on the percentage of stomata in tested woody species, horse chestnut and birch, under examined Banja Luka air pollution conditions. Two locations in Banja Luka town were examined, with different air pollution degrees: the first location is a hostel for students, with the minimal or absent air pollution; the second location is the west transit, with high air pollution due to a high number of motor cars which pass by the west transit. The air pollution difference between these two locations is very marked, and the objective of the examination was to assess how the indicated locations, which have different life conditions for the tested woody species, impact the physiological processes such as transpiration and photosynthesis. The study species react differently when the percentage of stomata and air pollution are compared.

  13. Combination treatment of elevated UVB radiation, CO2 and temperature has little effect on silver birch (Betula pendula) growth and phytochemistry.

    Science.gov (United States)

    Lavola, Anu; Nybakken, Line; Rousi, Matti; Pusenius, Jyrki; Petrelius, Mari; Kellomäki, Seppo; Julkunen-Tiitto, Riitta

    2013-12-01

    Elevations of carbon dioxide, temperature and ultraviolet-B (UBV) radiation in the growth environment may have a high impact on the accumulation of carbon in plants, and the different factors may work in opposite directions or induce additive effects. To detect the changes in the growth and phytochemistry of silver birch (Betula pendula) seedlings, six genotypes were exposed to combinations of ambient or elevated levels of CO2 , temperature and UVB radiation in top-closed chambers for 7 weeks. The genotypes were relatively similar in their responses, and no significant interactive effects of three-level climate factors on the measured parameters were observed. Elevated UVB had no effect on growth, nor did it alter plant responses to CO2 and/or temperature in combined treatments. Growth in all plant parts increased under elevated CO2 , and height and stem biomass increased under elevated temperature. Increased carbon distribution to biomass did not reduce its allocation to phytochemicals: condensed tannins, most flavonols and phenolic acids accumulated under elevated CO2 and elevated UVB, but this effect disappeared under elevated temperature. Leaf nitrogen content decreased under elevated CO2 . We conclude that, as a result of high genetic variability in phytochemicals, B. pendula seedlings have potential to adapt to the tested environmental changes. The induction in protective flavonoids under UVB radiation together with the positive impact of elevated CO2 and temperature mitigates possible UVB stress effects, and thus atmospheric CO2 concentration and temperature are the climate change factors that will dictate the establishment and success of birch at higher altitudes in the future.

  14. Inhaled birch pollen extract induces airway hyperresponsiveness via oxidative stress but independently of pollen-intrinsic NADPH oxidase activity, or the TLR4-TRIF pathway.

    Science.gov (United States)

    Shalaby, Karim H; Allard-Coutu, Alexandra; O'Sullivan, Michael J; Nakada, Emily; Qureshi, Salman T; Day, Brian J; Martin, James G

    2013-07-15

    Oxidative stress in allergic asthma may result from oxidase activity or proinflammatory molecules in pollens. Signaling via TLR4 and its adaptor Toll-IL-1R domain-containing adapter inducing IFN-β (TRIF) has been implicated in reactive oxygen species-mediated acute lung injury and in Th2 immune responses. We investigated the contributions of oxidative stress and TLR4/TRIF signaling to experimental asthma induced by birch pollen exposure exclusively via the airways. Mice were exposed to native or heat-inactivated white birch pollen extract (BPEx) intratracheally and injected with the antioxidants, N-acetyl-L-cysteine or dimethylthiourea, prior to sensitization, challenge, or all allergen exposures, to assess the role of oxidative stress and pollen-intrinsic NADPH oxidase activity in allergic sensitization, inflammation, and airway hyperresponsiveness (AHR). Additionally, TLR4 signaling was antagonized concomitantly with allergen exposure, or the development of allergic airway disease was evaluated in TLR4 or TRIF knockout mice. N-acetyl-L-cysteine inhibited BPEx-induced eosinophilic airway inflammation and AHR except when given exclusively during sensitization, whereas dimethylthiourea was inhibitory even when administered with the sensitization alone. Heat inactivation of BPEx had no effect on the development of allergic airway disease. Oxidative stress-mediated AHR was also TLR4 and TRIF independent; however, TLR4 deficiency decreased, whereas TRIF deficiency increased BPEx-induced airway inflammation. In conclusion, oxidative stress plays a significant role in allergic sensitization to pollen via the airway mucosa, but the pollen-intrinsic NADPH oxidase activity and TLR4 or TRIF signaling are unnecessary for the induction of allergic airway disease and AHR. Pollen extract does, however, activate TLR4, thereby enhancing airway inflammation, which is restrained by the TRIF-dependent pathway.

  15. CO2 elevation improves photosynthetic performance in progressive warming environment in white birch seedlings [v1; ref status: indexed, http://f1000r.es/up

    Directory of Open Access Journals (Sweden)

    Shouren Zhang

    2013-01-01

    Full Text Available White birch (Betula paperifera Mash seedlings were exposed to progressively warming in greenhouses under ambient and elevated CO2 concentrations for 5 months to explore boreal tree species’ potential capacity to acclimate to global climate warming and CO2 elevation. In situ foliar gas exchange, in vivo carboxylation characteristics and chlorophyll fluorescence were measured at temperatures of 26oC and 37oC. Elevated CO2 significantly increased net photosynthetic rate (Pn at both measurement temperatures, and Pn at 37oC was higher than that at 26oC under elevated CO2. Stomatal conductance (gs was lower at 37oC than at 26oC, while transpiration rate (E was higher at 37oC than that at 26oC. Elevated CO2 significantly increased instantaneous water-use efficiency (WUE at both 26oC and 37oC, but WUE was markedly enhanced at 37oC under elevated CO2. The effect of temperature on maximal carboxylation rate (Vcmax, PAR-saturated electron transport rate (Jmax and triose phosphate utilization (TPU varied with CO2, and the Vcmax and Jmax were significantly higher at 37oC than at 26oC under elevated CO2. However, there were no significant interactive effects of CO2 and temperature on TPU. The actual photochemical efficiency of PSII (DF/ Fm’, total photosynthetic linear electron transport rate through PSII (JT and the partitioning of JT to carboxylation (Jc were higher at 37oC than at 26oC under elevated CO2. Elevated CO2 significantly suppressed the partitioning of JT to oxygenation (Jo/JT. The data suggest that the CO2 elevation and progressive warming greatly enhanced photosynthesis in white birch seedlings in an interactive fashion.

  16. 白桦细胞悬浮培养产三萜及其营养成分消耗的动态%Kinetics of Triterpenoid Production and Nutrient Consumption in Birch (Betula platyphylla) Suspension Cell p

    Institute of Scientific and Technical Information of China (English)

    范桂枝; 翟俏丽; 于海娣; 王晓东; 王博; 詹亚光

    2011-01-01

    Effects of the basic media and inoculum size on birch cell growth and the triterpenoid production were investigated using birch suspension cells, on this basis, the kinetic relationships of birch cell growth, triterpenoid production and nutrient consumption were also analyzed. The results showed the opbimal conditions for the birch cell growth and triterpenoid production were 20 ~ 30 g· L-1(FW) of inoculum size, in B5 medium. The kinetics analysis for birch cell suspension culture showed that triterpenoid production was increasing with the birch cell growth during a cell subculture cycle. During the teriod, the maximum specific growth rate was 0. 18 on the 12th day, and the maximum triterpenoid synthesis rate was 0.73 mg· g-1 on the 9th day. Sugar, NO3- , NH+4 and PO34- in the culture medium were nearly used up on the 9th day, The content of sugar, NO-3 , and PO34- in birch cell were highest on 6th day, but the content of NH+4 in birch cell were higher on 3th day. The results snggested that the nutrient deficiencies in medium wonld limited the cell rapid multiplication and triterpenoid content accumulation.%以产三萜的白桦悬浮系为试验材料,在优化白桦悬浮细胞生长与三萜积累的培养基种类和接种量的基础上,分析白桦悬浮细胞生长和三萜积累的动力学关系,同时考察1个培养周期内白桦细胞内外主要营养成分的变化.结果表明:1)在MS,NT,IS,WPM,1/2MS,B5 6种培养基和10~40 g·L-1接种量中,有利于白桦细胞生长和三萜生产的培养基为B5和接种量为20~30 g·L-1 FW;2)在1个培养周期内,白桦悬浮细胞培养过程中三萜的产量与细胞生物量是相偶联的,随着生物量的增加三萜产量呈增长趋势,其中,白桦细胞在第12天比生长速率达到最高0.18,三萜合成速率和比合成速率在第9天达到最高值,分别为0.73 mg·g-1和0.06;3)在白桦细胞培养的1个周期内,培养液中的蔗糖,NO3,NH+4和PO3-4在细胞培养的第9天

  17. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe;

    2003-01-01

    Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch.......001). These results show that high avidity IgG of low inter-individual difference in Bet v 1 binding quality is the dominant binding factor of Bet v 1 in sera of birch pollen-allergic patients, and that SAV-induced inhibition of binding of Bet v 1 to IgE can be explained mainly or solely by increased amounts of IgG....

  18. 天然白桦种苗光合作用日进程%Daily Course of Photosynthesis in Seedlings of Natural Birch

    Institute of Scientific and Technical Information of China (English)

    王爱民; 刘志学; 祖元刚

    2001-01-01

    In this research, the most advanced system for photosynthesis-LI 6400 was used in seedlings of natural birch which is one kind of multi-function species. The diurnal course of photosynthetic rate of birch shows a single peak (10.53 μ molCO2 m-2s-1) which reaches at 14 o'clock. There exist no “midday depression” in the photosynthesis. At 14 o'clock, while the value of stoma limitation (0.3172) and water pressure deficits of leaf (2.46 kPa) reach their peaks, the water utilization efficiency is still high and the highest value (2.97 μ1 molCO2 m-2 s-1 mm H2O m-2s-1) appears at 12 o'clock. And the most value of apparent quantum yield occurs at 8 o'clock. But the climax value of transpiration rate appears at 14 o'clock (4.82 mmH2O m-2s-1). In the diurnal variation of photosynthetic rate, high value keeps on during at least 4 hours. This increase the amount of photosynthesis in daily course, furthermore, it makes advantage to the growth of birch.%本研究采用最先进的光合作用测定系统LI-6400测定多功能树种白桦种苗的光合作用.天然白桦种苗光合速率日进程表现为 单峰曲线,在下午14:00时达到最高峰(10.53 μ mol CO2 m-2 s-1),.其光合作用不存在“午休现象”.在14:00时,白桦的气孔限制值 (0.3172)和水分饱和亏缺(2.46 kPa)分别达到最大值,此时其水分利用效率较高,在中午12:00时水分利用率达到最大值(2.97μ molCO2m-2 s-1mmH2Om-2s-1).在早上8:00,白桦获得一天中最大的表观量子效率;其蒸腾速率在下午14:00时最大(4.82mmH2O m-2s-1).在光合速率的日进程中,白桦高光合速率值持续至少4个小时.这使得白桦的光合作用量得以有效累积,进而为其生长创 造了有利条件.

  19. Changes in flowering of birch in the Czech Republic in recent 25 years (1991–2015 in connection with meteorological variables

    Directory of Open Access Journals (Sweden)

    Lenka Hajkova

    2015-12-01

    Full Text Available The paper presents the results of long-term phenological observations of silver birch (Betula pendula during the years 1991–2015 across the phenological network of the Czech Hydrometeorological Institute (CHMI – Český hydrometeorologický ústav. The data assembled over this period were used for identification of timing of generative phenophases associated with pollen release into the air: inflorescence emergence 10%, beginning of flowering 10%, beginning of flowering 50%, beginning of flowering 100%, and end of flowering. The stations are situated at altitudes from 155 m (Doksany to 1102 m (Modrava. The average timing of beginning of flowering 10% was 8th April (Lednice = lowland station and 14th May (Modrava = mountain station; the average timing of beginning of flowering 50% was 12th April (Lednice and 20th May (Modrava; the average timing of beginning of flowering 100% was 18th April (Lednice and 22nd May (Modrava, and the average timing of end of flowering was 26th April (Lednice and 28th May (Modrava. The totals of effective temperatures above 5°C (TS5 and sums of daily precipitation were used as a bio-climatological criterion for assessment of the dependence of phenological phases on meteorological variables. The average sums of TS5 and the average sums of daily precipitation total were as follows: 61.0–80.8°C, 82.8–327.4 mm (inflorescence emergence; 105.2–106.4°C, 85.9–365.2 mm (beginning of flowering 10%; 124.8–130.8°C, 89.8–385.9 mm (beginning of flowering 50%; 144.7–158.6°C, 95.2–390.7 mm (beginning of flowering 100%; and 181.6–223.8°C, 104.7–427.4 mm (end of flowering. Synoptic situations occurring during interphase intervals were obtained – the most often found synoptic situations were B (stationary trough over Central Europe, Bp (east travelling trough, NEa (northeast anticyclonic situation, Sa (south anticyclonic situation and SWc2 (southwest cyclonic situation moving northeast to eastwards. The

  20. A comparison of species composition and community assemblage of secondary forests between the birch and pine-oak belts in the mid-altitude zone of the Qinling Mountains, China.

    Science.gov (United States)

    Chai, Zongzheng; Wang, Dexiang

    2016-01-01

    The mid-altitude zone of the Qinling Mountains in China was once dominated by birch and pine-oak belts but are now mainly covered by secondary growth following large-scale deforestation. Assessing the recovery and sustainability of these forests is essential for their management and restoration. We investigated and compared the tree species composition and community assemblages of secondary forests of the birch and pine-oak belts in the Huoditang forest region of the Qinling Mountains after identical natural recoveries. Both types of belts had rich species compositions and similar floristic components but clearly different community structures. Tree diversity was significantly higher for the birch than the pine-oak belt. Niche and neutral processes simultaneously influenced the species distribution and community dynamics of the belts, and these forests were able to maintain stable development during natural recoveries. The conservation and management of these forests should receive more attention to protect biodiversity and the forest resources in the Qinling Mountains. PMID:27123377

  1. The effects of soil and air temperature on CO2 exchange and net biomass accumulation in Norway spruce, Scots pine and silver birch seedlings.

    Science.gov (United States)

    Pumpanen, Jukka; Heinonsalo, Jussi; Rasilo, Terhi; Villemot, Julie; Ilvesniemi, Hannu

    2012-06-01

    Soil temperature is proposed to affect the photosynthetic rate and carbon allocation in boreal trees through sink limitation. The aim of this study was to investigate the effect of temperature on CO(2) exchange, biomass partitioning and ectomycorrhizal (ECM) fungi of boreal tree species. We measured carbon allocation, above- and below-ground CO(2) exchange and the species composition of associated ECM fungi in the rhizosphere of Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies K.) and silver birch (Betula pendula Roth) seedlings grown in soil maintained at 7-12, 12-15 and 16-22 °C. We found increased root biomass and photosynthetic rate at higher soil temperatures, but simultaneously with photosynthesis rate, higher temperature generally increased soil respiration as well as shoot, and root and rhizosphere respiration. The net CO(2) exchange and seedling biomass did not increase significantly with increasing temperature due to a concomitant increase in carbon assimilation and respiration rates. The 2-month-long growth period in different soil temperatures did not alter the ECM fungi species composition and the below-ground carbon sink strength did not seem to be directly related to ECM biomass and species composition in any of the tree species. Ectomycorrhizal species composition and number of mycorrhiza did not explain the CO(2) exchange results at different temperatures.

  2. The seasonal symptoms of hyposensitized and untreated hay fever patients in relation to birch pollen counts: correlations with nasal sensitivity, prick tests and RAST.

    Science.gov (United States)

    Viander, M; Koivikko, A

    1978-07-01

    A 2 year prospective study of thirty-eight birch pollen-sensitive hay fever patients under specific immunotherapy and of nineteen untreated control patients showed a significant correlation between the total seasonal symptom scores of the patients and their clinical sensitivities assessed by the RAST and a graded nasal test. The agreement between a positive nasal test and a positive RAST was 74%. In the early season with low pollen counts the onset of symptoms was significantly associated with high sensitivity of the patients, while many patients showed symptoms in the late season irrespective of their nasal and RAST sensitivity. About 90% of both the treated and the untreated patients reported mild symptoms when the pollen count exceeded 80/m(3) in the early season. 80% of them still had symptoms when the count was below 30/m(3) in the late pollen season. Although hyposensitization therapy had no effect on the occurrence of the mild symptoms, the treated patinets had severe symptoms significantly less often than the untreated ones on days with high pollen counts.

  3. Changes of the "Birch effect" in a course of post-agrogenic successions in abandoned fellows along the N-S transect from south taiga Podzols to dry steppe Calcisol-Solonetz soil complexes (European Russia)

    Science.gov (United States)

    Karelin, Dmitry; Chestnykh, Olga; Rostovceva, Elena

    2016-04-01

    This chronosequential longitudinal (58 - 48oN) study in European Russia includes measurements of the dynamics of soil respiration and changes of the so called "Birch effect" during different stages of self-restoration in post-agrogenic south taiga Pogzols (1, 7, 23, 55, 100, 170 yr after abandonment); Haplic Luvisols in the temperate broadleaf forest zone (1, 3, 7, 20, 60, 110 yr); forest-steppe Chernozems (1, 2, 8, 38, 66 yr), and Calcisol-Solonetz complexes in the dry steppe zone (1, 7, 12, 17 and 42 yr). This effect is well known in soil ecology studies (Birch, 1954) and results in intensive rise of surface CO2 emission and nitrogen release due to soil moistening after drought events. Measurements of the "Birch effect" in the agro-ecosystems were made in 2012 - 2015 during the vegetative periods (April- September). We measured CO2 emissions monthly at every succession stage, using a closed chamber technique before and after 200 ml of distilled water addition per base (equivalent of 2 mm rain). The maximum rates of observed CO2 soil emission fluxes due to "Birch effect" per initial respiration values were than compared between different zonal ecosystems and stages of agro-successions. Our results show that the fellows stages in dry steppe zone demonstrate the lowest seasonal rate of basic soil respiration at average: 3.5 times lower, if compared to the fellows chronosequence in Podzols, 4.6 times lower, if compared to Agro-chernozems, and the maximum difference was found with the Haplic Livisols in the zone of broadleaf forests - 7.8 times lower. The "Birch effect" for soil respiration of the zonal fellow chronosequences in study was shown to increase from 1.1 ± 0.6 for broadleaf Haplic Vertisols (no effect), to 7.1 ± 1.5 in the zone of forest steppe, and to 15.2 ± 3.5 in dry steppe, which is due to zonal deterioration of hydro-thermal conditions and aridization. In south taiga zone it is weakly expressed and changes within the limits of 1.0 - 2.5. In

  4. The Presence of Pretreated Lignocellulosic Solids from Birch during Saccharomyces cerevisiae Fermentations Leads to Increased Tolerance to Inhibitors--A Proteomic Study of the Effects.

    Directory of Open Access Journals (Sweden)

    Rakesh Koppram

    Full Text Available The fermentation performance of Saccharomyces cerevisiae in the cellulose to ethanol conversion process is largely influenced by the components of pretreated biomass. The insoluble solids in pretreated biomass predominantly constitute cellulose, lignin, and -to a lesser extent- hemicellulose. It is important to understand the effects of water-insoluble solids (WIS on yeast cell physiology and metabolism for the overall process optimization. In the presence of synthetic lignocellulosic inhibitors, we observed a reduced lag phase and enhanced volumetric ethanol productivity by S. cerevisiae CEN.PK 113-7D when the minimal medium was supplemented with WIS of pretreated birch or spruce and glucose as the carbon source. To investigate the underlying molecular reasons for the effects of WIS, we studied the response of WIS at the proteome level in yeast cells in the presence of acetic acid as an inhibitor. Comparisons were made with cells grown in the presence of acetic acid but without WIS in the medium. Altogether, 729 proteins were detected and quantified, of which 246 proteins were significantly up-regulated and 274 proteins were significantly down-regulated with a fold change≥1.2 in the presence of WIS compared to absence of WIS. The cells in the presence of WIS up-regulated several proteins related to cell wall, glycolysis, electron transport chain, oxidative stress response, oxygen and radical detoxification and unfolded protein response; and down-regulated most proteins related to biosynthetic pathways including amino acid, purine, isoprenoid biosynthesis, aminoacyl-tRNA synthetases and pentose phosphate pathway. Overall, the identified differentially regulated proteins may indicate that the likelihood of increased ATP generation in the presence of WIS was used to defend against acetic acid stress at the expense of reduced biomass formation. Although, comparative proteomics of cells with and without WIS in the acetic acid containing medium

  5. The Presence of Pretreated Lignocellulosic Solids from Birch during Saccharomyces cerevisiae Fermentations Leads to Increased Tolerance to Inhibitors--A Proteomic Study of the Effects.

    Science.gov (United States)

    Koppram, Rakesh; Mapelli, Valeria; Albers, Eva; Olsson, Lisbeth

    2016-01-01

    The fermentation performance of Saccharomyces cerevisiae in the cellulose to ethanol conversion process is largely influenced by the components of pretreated biomass. The insoluble solids in pretreated biomass predominantly constitute cellulose, lignin, and -to a lesser extent- hemicellulose. It is important to understand the effects of water-insoluble solids (WIS) on yeast cell physiology and metabolism for the overall process optimization. In the presence of synthetic lignocellulosic inhibitors, we observed a reduced lag phase and enhanced volumetric ethanol productivity by S. cerevisiae CEN.PK 113-7D when the minimal medium was supplemented with WIS of pretreated birch or spruce and glucose as the carbon source. To investigate the underlying molecular reasons for the effects of WIS, we studied the response of WIS at the proteome level in yeast cells in the presence of acetic acid as an inhibitor. Comparisons were made with cells grown in the presence of acetic acid but without WIS in the medium. Altogether, 729 proteins were detected and quantified, of which 246 proteins were significantly up-regulated and 274 proteins were significantly down-regulated with a fold change≥1.2 in the presence of WIS compared to absence of WIS. The cells in the presence of WIS up-regulated several proteins related to cell wall, glycolysis, electron transport chain, oxidative stress response, oxygen and radical detoxification and unfolded protein response; and down-regulated most proteins related to biosynthetic pathways including amino acid, purine, isoprenoid biosynthesis, aminoacyl-tRNA synthetases and pentose phosphate pathway. Overall, the identified differentially regulated proteins may indicate that the likelihood of increased ATP generation in the presence of WIS was used to defend against acetic acid stress at the expense of reduced biomass formation. Although, comparative proteomics of cells with and without WIS in the acetic acid containing medium revealed numerous

  6. The Presence of Pretreated Lignocellulosic Solids from Birch during Saccharomyces cerevisiae Fermentations Leads to Increased Tolerance to Inhibitors – A Proteomic Study of the Effects

    Science.gov (United States)

    Koppram, Rakesh; Mapelli, Valeria; Albers, Eva; Olsson, Lisbeth

    2016-01-01

    The fermentation performance of Saccharomyces cerevisiae in the cellulose to ethanol conversion process is largely influenced by the components of pretreated biomass. The insoluble solids in pretreated biomass predominantly constitute cellulose, lignin, and -to a lesser extent- hemicellulose. It is important to understand the effects of water-insoluble solids (WIS) on yeast cell physiology and metabolism for the overall process optimization. In the presence of synthetic lignocellulosic inhibitors, we observed a reduced lag phase and enhanced volumetric ethanol productivity by S. cerevisiae CEN.PK 113-7D when the minimal medium was supplemented with WIS of pretreated birch or spruce and glucose as the carbon source. To investigate the underlying molecular reasons for the effects of WIS, we studied the response of WIS at the proteome level in yeast cells in the presence of acetic acid as an inhibitor. Comparisons were made with cells grown in the presence of acetic acid but without WIS in the medium. Altogether, 729 proteins were detected and quantified, of which 246 proteins were significantly up-regulated and 274 proteins were significantly down-regulated with a fold change≥1.2 in the presence of WIS compared to absence of WIS. The cells in the presence of WIS up-regulated several proteins related to cell wall, glycolysis, electron transport chain, oxidative stress response, oxygen and radical detoxification and unfolded protein response; and down-regulated most proteins related to biosynthetic pathways including amino acid, purine, isoprenoid biosynthesis, aminoacyl-tRNA synthetases and pentose phosphate pathway. Overall, the identified differentially regulated proteins may indicate that the likelihood of increased ATP generation in the presence of WIS was used to defend against acetic acid stress at the expense of reduced biomass formation. Although, comparative proteomics of cells with and without WIS in the acetic acid containing medium revealed numerous

  7. A K-ANONYMITY PUBLISHING ALGORITHM FOR DATA STREAMS BASED ON IMPROVED BIRCH MODEL%一种基于BIRCH改进模型的数据流K-匿名发布算法

    Institute of Scientific and Technical Information of China (English)

    王璞; 陆剑江; 赵雷; 杨季文

    2011-01-01

    针对数据流持续、实时等特征,提出了一种基于BIRCH层次聚类的K-匿名隐私保护发布算法,改进了原BIRCH聚类模型,对准标识符中不同类型的属性进行同一度量映射,由聚类特征可加性合并了CF树中的相关子簇,控制了单个元组的最大发布时延.实验表明该方法具有良好的隐私保护效果和信息利用水平.%In this paper we propose a k-anonymity privacy protection publishing algorithm based on hierarchical clustering technology of BIRCH for the characteristics of persistence and real-time of data streams, and make some improvements on original BIRCH clustering model.Same metric mapping is used on different attributes in quasi-identifiers and the corresponding sub-clusters in CF-Tree are merged via the additivity of the clustering features, thus the maximum release delay of a single tuple is in control.Experiments show that this algorithm has good effect on privacy protection and information utility.

  8. Vaccination for birch pollen allergy

    DEFF Research Database (Denmark)

    Jakobsen, C G; Bodtger, U; Poulsen, Lars K.;

    2005-01-01

    Allergen-specific immunotherapy (SIT) is associated with increased levels of allergen-specific IgG in serum. However, it is not clear to what extent qualitative changes in the allergen binding capacity of IgG may be induced as well....

  9. 桦树花粉、大豆和苹果过敏原之间高免疫球蛋白E 相关性表明中国北方地区桦树花粉过敏患者很可能同时患有花粉-食物综合征%High correlation of specific IgE sensitization between birch pollen, soy and apple allergens indicates pollen-food allergy syndrome among birch pollen allergic patients in northern China

    Institute of Scientific and Technical Information of China (English)

    Guo-dong HAO; Yi-wu ZHENG; Zhi-xiang WANG; Xing-ai KONG; Zhi-jing SONG; Xu-xin LAI; Michael D SPANGFORT

    2016-01-01

    目的:研究中国北方地区桦树花粉过敏及花粉–食物过敏综合征。  创新点:国内首次研究花粉–食物过敏综合征,为中国北方地区此类患者的诊断和治疗提出了新思路。  方法:采集临床中过敏患者血清,检测桦树花粉及其主要过敏原特异性免疫球蛋白 E(IgE),同时检测大豆和苹果过敏原的特异性IgE,并评价其相关性。  结论:中国北方地区桦树花粉季节对此花粉过敏的患者有16.7%以上,主要是对桦树花粉第一组过敏原致敏。这些患者大多数同时对大豆和苹果的主要过敏原过敏,这种特异性IgE高相关性说明临床上存在花粉–食物过敏综合征。%Background: Birch pollen sensitization and associated pol en-food syndrome among Chinese al ergic patients have not been investigated. Methods: Sera from 203 al ergic patients from the northern part of China and col ected during February to July 2014 were investigated. Specific immunoglobulin E (IgE) against birch pol en extract Bet v and major birch pollen allergen Bet v 1 were measured using the ADVIA Centaur. The presence of major apple al ergen Mal d 1 and soy bean al ergen Gly m 4 specific IgE was measured by ImmunoCAP 100. Results:Among the 203 sera, 34 sera (16.7%) had specific IgE to Bet v and of these, 28 sera (82.4%) contained Bet v 1-specific IgE. Among the 28 sera with Bet v 1-specific IgE, 27 sera (96.4%) contained Mal d 1-specific IgE and 22 sera (78.6%) contained Gly m 4-specific IgE. Of the 34 Bet v-positive sera, 6 sera (17.6%) contained no specific IgE for Bet v 1, Mal d 1, or Gly m 4. Almost al Bet v-positive sera were donated during the birch pollen season. Conclusions:The prevalence of birch al ergy among patients visiting health care during pol en season can be as high as 16.7%in Tangshan City. The majority of Chinese birch al ergic patients are IgE-sensitized to the major birch pol en al ergen Bet v 1 as wel as to the

  10. 桦树皮提取物对荷瘤小鼠免疫抑瘤效应的研究%Study of extraction of birch bark (EBB) on immune inhibition tumor effect in bearing tumor mice

    Institute of Scientific and Technical Information of China (English)

    韩淑英; 吴子忠; 熊建新; 李岩; 宗瑞义

    2002-01-01

    目的:研究桦树皮提取物(Extraction of Birch Bark EBB)对S180荷瘤小鼠体内抑瘤效应及其对免疫功能的影响.方法:应用EBB口服观察其对肿瘤的抑制作用,并检测脾细胞对ConA刺激的反应性和NK、TNF、IL-2的活性.结果:EBB可明显地抑制肿瘤生长,提高荷瘤鼠脾细胞对ConA刺激的反应性、并明显增强NK细胞活性、促进TNF和IL-2分泌增加.结论:EBB增强荷瘤鼠免疫功能可能是其抑瘤效应的机制.

  11. 多重干湿交替格局下土壤Birch效应的响应机制%The Response of Birch Effect Under Multiple Wet-dry Cycles

    Institute of Scientific and Technical Information of China (English)

    王君; 宋新山; 严登华; 陈燕

    2013-01-01

    为了探究多重干湿交替格局及土壤团聚体粒径对土壤呼吸作用尤其是Birch效应的影响机理,以3种不同团聚体粒径的表层土(0~20 cm)为受试土壤,通过采用室内孵育试验的方法,研究了多重干湿交替循环及不同土壤团聚体粒径对Birch效应产生的影响。结果表明:复水促进了土壤呼吸作用,增加了土壤微生物生物量,但对微生物量和呼吸作用产生的激增效应并没有持续很长时间。复水3h后呼吸速率达到峰值,并且随着干湿周期频率的增加而降低,其中大土粒降低幅度最小。不同土壤团聚体粒径对Birch效应的影响强度不同,但二者并不是简单的线性关系。总之,土壤团聚体能够保护部分有机质不被微生物分解矿化,多重干湿交替干扰了这种保护作用,提高了有机碳的生物相容性。Birch效应中被矿化的有机碳更多是来自于新的有机质的暴露,部分来自干旱期微生物细胞内积累的溶质。值得注意的是随着干湿循环数的增加,被暴露的新的有机质在被矿化分解前可能还存在其他中间过程。%In order to research the effect of multiple wet-dry cycles and soil aggregate size on soil respiration especially Birch effect, based on three different aggregate size surface soil (0-20 cm) for the tested soil, through the use of indoor incubation test method, research the multiple wet-dry cycles and different soil aggregate size to Birch effect. The results showed that, after water promoted the soil respiration, increased the soil microbial biomass, but the surge effect did not last long. Respiratory rate was peak after rewet 3 h, and the more wet-dry cycles, the lower respiration rate. Different soil aggregate grain size of Birch effect of strength different, but they had not a simple linear relationship. The results also showed that, the soil aggregates could protect soil organic matter from decomposing by microbe

  12. Comparision of the Cytotoxic Effects of Birch Bark Extract, Betulin and Betulinic Acid Towards Human Gastric Carcinoma and Pancreatic Carcinoma Drug-sensitive and Drug-Resistant Cell Lines

    Directory of Open Access Journals (Sweden)

    Hermann Lage

    2009-04-01

    Full Text Available Betulin and betulinic acid are naturally occurring pentacyclic triterpenes showing cytotoxicity towards a number of cancer cell lines. These compounds can be found in the bark of the many plants. In this report we have compared the cytotoxic activity of crude birch bark extract and purified betulin and betulinic acid towards human gastric carcinoma (EPG85-257 and human pancreatic carcinoma (EPP85-181 drug-sensitive and drug-resistant (daunorubicin and mitoxantrone cell lines. Our results show significant differences in sensitivity between cell lines depending on the compound used, and suggest that both betulin and betulinic acid can be considered as a promising leads in the treatment of cancer.

  13. Bio energy production in birch and hybrid aspen after addition of residue based fertilizers - establishment of fertilization trials; Bioenergiproduktion hos bjoerk och hybridasp vid tillfoersel av restproduktbaserade goedselmedel - etablering av goedslingsfoersoek

    Energy Technology Data Exchange (ETDEWEB)

    Thelin, Gunnar (EkoBalans Fenix AB, Malmoe (Sweden))

    2009-03-15

    Sewage sludge and wood ashes could be used as fertilizers in order to increase forest tree production. In southern Sweden forest growth normally increases with approximately 10 % after ash recycling due to increased N and/or P availability. P is added with the ashes and the pH-increasing effect of the wood ash can lead to increased N net mineralization. Other positive effects of wood ash recycling are improved nutrient sustainability and less acid run-off water. Possible negative effects are heavy metal accumulation, if the content of one or more heavy metals of the recycled ash exceeds the heavy metal content of the harvested biomass, and nitrate leaching if the vegetation cannot take up nitrified N. It is important to evaluate the sustainability of fertilization systems based on residues such as sludge and wood ash. Wood ash does not contain N and the P concentration often is too low for the ashes to function as an NP fertilizer. Thus N and sometimes P must be added. Sludge is an interesting alternative. The main purpose of the project is to study sustainable production of forest bio energy in intensively cultivated birch and hybrid aspen stands. Another purpose is to establish experiments that can be used for long term studies and as demonstration objects. In the first few years the goal is to study the short term effects of residue based fertilization compared to conventional NPK fertilization on tree nutrient uptake, nutrient leaching, sustainability and economy. In the long term the goal is to design appropriate fertilization strategies in a residue based fertilization system for the intensive cultivation of birch and hybrid aspen without negative side effects such as large scale nutrient leaching. Four field experiments were established in 2008 and one additional experiment in hybrid aspen will be established in the spring of 2009. Elevated bud N and P concentrations after fertilization with both Ashes+N and NPK means good possibilities for future growth

  14. Vaccination for birch pollen allergy. Induction of affinity-matured or blocking IgG antibodies does not account for the reduced binding of IgE to Bet v 1

    DEFF Research Database (Denmark)

    Svenson, Morten; Jacobi, Henrik H; Bødtger, Uffe;

    2003-01-01

    Specific allergy vaccination (SAV) is associated with increased levels of allergen specific IgG in serum. It is not clear, however, to what extent qualitative changes in allergen binding to IgG may be induced as well. We therefore analyzed the binding of the major allergen in pollen of birch...... the amount of Bet v 1 compared with IgE, and together they accounted for more than 85% of the serum binding capacity. While SAV induced minimal changes in IgE binding, the IgG binding capacities increased 6-32 times. In contrast, the binding avidities (K(d) 28-40pM) changed less than 20%, pre- and post...

  15. A New Rapid Drying Technique for 2.5 cm-thick Birch Floor Planks%2.5 cm桦木地板毛坯快速干燥新工艺

    Institute of Scientific and Technical Information of China (English)

    李增超; 邱增处; 雷亚芳; 杨庆

    2001-01-01

    用干球温度不变、湿球温度连续降低的干燥新工艺对2.5 cm桦木地板毛坯进行快速窑干,使干燥周期较常规窑缩短了40%,干燥质量好,且易于操作。%This article shows the experiment on the rapid kiln drying for 2.5 cm-thich birch floor blanks,in which such drying technique is used as constant temperature of dry bulb and continuous temperature decrease of wet bulb.As a result,drying period is shortened by 40%,compared with ordinary kilning.Besides,it is high in quality and easy in operation.

  16. An improved BIRCH clustering method for radar reconnaissance data based on extremum features%基于极值特征的雷达侦察数据BIRCH聚类方法

    Institute of Scientific and Technical Information of China (English)

    张宇

    2016-01-01

    为解决传统BIRCH算法对数据对象输入顺序敏感、聚类结果不稳定的问题,提出了一种改进的BIRCH算法。该算法将雷达信号侦察数据的脉冲载频、脉冲重复间隔和脉冲宽度分别进行聚类,根据工程应用中各参数量测误差和系统误差设定不同阈值。并且引入聚类簇的极大极小值作为聚类特征,使用层次树的方法来构建聚类特征模型,实现了雷达侦察数据的快速向下搜索及聚类。实验结果表明,该方法是可行、有效的。%In order to solve the problem that traditional BIRCH clustering algorithms are sensitive to the data input order with unstable clustering results, an improved BIRCH clustering algorithm is proposed. In this method, the RF, PRI and PW values of radar reconnaissance data are clustered as three separate parameters. In engineering application, different threshold is set according to the parameter measurement error and system error. The maximum and minimum of clusters are used as clustering features to construct the clustering feature model by using hierarchical tree method. The searching and clustering for radar reconnaissance data can be quickly achieved. Experimental results show that the proposed method is feasible and effective.

  17. Effects of Water,Nitrogen and Methyl Jasmonate Treatment on Triterpenes Accumulation in Birch (Betula platyphylla Suk.)%水分、氮肥及MeJA处理对白桦三萜积累特性的影响

    Institute of Scientific and Technical Information of China (English)

    李春晓; 尹静; 詹亚光; 任春林; 王智慧

    2012-01-01

    With one year and a half birch saplings as experimental materials, we investigated the effects of water,nitrogen and methyl jasmonate(MeJA) treatment on the accumulation of triterpenes and the accumulated regulation of triterpenes in birch. The results showed that,total triterpene is mainly distributed in stem bark and leaf in birch sapling,the average content is 71. 94 mg · G-1 and 81. 60 mg · G-1 respectively, and the lowest in root bark, which is 25. 45 mg · G-1. The accumulated peak of total triterpene in leaf is June and July;But accumulated peaks of total triterpene in stem bark and root bark are August and July, respectively. Moderate and severe drought stress had significantly contributed to the accumulation of total triterpene in leaf in the early stage of drought stress,which are 1. 24 and 1. 27 times of the control. The accumulation of total triterpene for water stress in stem bark is significantly higher than at of control in July.Water stress has not conducived to total triterpene accumulation of the stem bark in other months. In addition, drought stress is adverse to triterpene accumulation in the root bark. Nitrogen treatment in early stage (June) is not conducive to triterpenoids accumulation in the leaves and root bark,but has remarkably contributed to the triterpenoids accumulation in late stage (July-October). However, the nitrogen treatment has contributed to the triterpenoids accumulation in the stem bark in early stage (June-July). MeJA spraying has promoted the triterpenes accumulation in the leaf and root bark. In the accumulating peak stage, with 1. 52 and 1. 42 times of the control. Light drought, nitrogen fertilizer both contribute to height growth and biomass accumulation of birch saplings, but MeJA treatment is disadvantage on the whole plant bio-mass accumulation.%以一年半生白桦幼树为试材,研究水分、氮肥和茉莉酸甲酯(MeJA)处理对白桦三萜物质积累的影响,并对白桦植株中三萜积累规

  18. Based Intrusion Detection Model Poly Type BIRCH Algorithm Design and Realization%基于聚类型BIRCH算法进行数据挖掘的入侵检测模型设计与实现

    Institute of Scientific and Technical Information of China (English)

    吴春琼

    2013-01-01

      随着网络时代的发展,信息安全己成为系统运行时的重要组成部分。传统意义上的防火墙无法抗击新网络入侵,不能系统提供有效的保护。本文介绍了入侵检测以及分类,数据挖掘中的聚类模式以及BIRCH算法,并分析它们的特性。最后使用KDD CUP 1999数据库进行模拟运行测试程序,并给出结果。%With the development of the Internet age, information security has become an important part of the system is running. The firewall can not fight against the new network intrusion in the traditional sense, can not provide effective protection. This article describes the intrusion detection and classification, data mining, clustering mode and BIRCH al-gorithm, and analyze their characteristics. Finally, use the KDD CUP 1999 database simulation run the test program, and gives the results.

  19. Difference of Litter Carbon Densityi n Natural Secondary Birches-Mongolian Oak Forest%天然次生白桦林蒙古栎林凋落物碳密度的差异

    Institute of Scientific and Technical Information of China (English)

    丁壮; 尚杰

    2015-01-01

    We measured and calculated the carbon density of litter fall in natural secondary birch -mongolian oak forest in the north of Changbai Mountain and Zhangguangcai Mountain .The litter carbon density in 42-year-old birch forest was 2.477 t· hm-2· a-1, and 1.049 t· hm-2· a-1 for 20-year-old birch forest, with difference of 136.13%.Litter carbon density in 20-year -old Mongolic oak forest was 0.948 t· hm-2 · a-1 , and 2.686 t· hm-2 · a-1for the 50-year-old Mongolic oak forest , with the deviation of 183.33%, and with the significance ANOVA result of ( P0.05) although in quantitative terms .The average value of carbon density in litter organs showed outstanding difference (P<0 .05) with leaf, branch, skin, fruit, dung, and ovum in the proper order , and the value rose with the forest age .Seasonal trend of carbon density in birch and Mongolic oak forest was regular and was divided into three stages according to the characteristics of carbon density trend , that was litter fall in growing season , litter fall in stop grow-ing season and winter dormancy with the highest value in the stop growing season , and the lowest in the winter dormancy .%在长白山北部、张广才岭西坡,东北林业大学老山人工林实验站,测试与计算天然次生白桦林( Betu-la platyphylla Suk.)和蒙古栎林(Quercus mongolica Fisch.ex Ledeb.)凋落物碳密度。结果表明:20年生白桦林凋落物碳密度为1.049 t· hm-2· a-1,42年生白桦林凋落物碳密度为2.477 t· hm-2· a-1,相差136.13%;20年生蒙古栎林凋落物碳密度为0.948 t· hm-2· a-1,50年生蒙古栎林凋落物碳密度为2.686 t· hm-2· a-1,相差183.33%;经方差分析,均相差显著( P<0.05),说明林龄是影响碳密度变化的主要因素。2种林分类型凋落物碳密度的变化,经方差分析均无显著(P >0.05),在数量上虽有小的差异,但在理论上没有变化。不同

  20. Water Conservation of Litterfall in Different Mixed Forest Types of White Birch and Larch in Daxing’ an Moun- tain%大兴安岭不同类型白桦落叶松混交林枯落物水源涵养功能1)

    Institute of Scientific and Technical Information of China (English)

    李红振; 李凤日; 贾炜玮; 王树芳

    2014-01-01

    With the data of four 40 m ×40 m sample plots from primary larch forest and conifer-hardwood mixed forest in the Huzhong National Nature Reserve in Daxing’an mountain, we studied the water conservation of the litterfall in larch forest, and white birch (Betula platyphylla) and Larch (Larix gmelini) mixed forest with different tree composition.We meas-ured the accumulation and water holding capacity for different litterfall component for each plot.The accumulation and wa-ter holding capacity of forest litter of different forest type are 17.46 t/hm2-22.48 t/hm2 and 60.30 t/hm2-81.48 t/hm2 , respectively .They both have significant difference among different forest types and both decrease with the reduction of larch ratio, i.e., 10 Larch>8 Larch 2 White birch>6 Larch 4 white birch>4 Larch 6 White birch.The sequence of the ef-fective to the rainfall of the different forest litterfall in the various tree compositions is 4 Larch 6 White birch>6 Larch 4 white birch>10 Larch>8 Larch 2 White birch.There is the highest correlation between the effective interception of the semi-decomposed and the rainfall with the correlation coefficient of 0.820.%以大兴安岭地区呼中国家自然保护区针阔混交的原始林为研究对象,在不同树种组成的林分中设置4块40 m×40 m标准地,通过枯落物不同组分累积量以及持水量的测定、计算和分析,对落叶松林和白桦-落叶松混交林枯落物水源涵养功能进行了研究。结果表明:各类型林分的枯落物干物质累积量为17.46~22.48 t/hm2,枯落物最大持水量为60.30~81.48 t/hm2,两者均在各林分间差异显著,都随着落叶松所占比例的减小而减小,由大到小顺序为:10落、8落2白、6落4白、4落6白。不同树种组成的林分枯落物对降雨的有效拦蓄量由高到低的顺序是4落6白、6落4白、10落、8落2白,且与半分解有效拦蓄量相关性最高,相关系数达到0.820。

  1. Comparison study on stand structures and naturalness between middle-aged and young secondary poplar-birch forest%杨桦中幼龄次生林结构与自然度的比较研究

    Institute of Scientific and Technical Information of China (English)

    霍艳玲; 金辉; 赵海玉; 王志彬; 刘丽颖; 黄龙生; 李永宁

    2014-01-01

    杨桦次生林是冀北山地的典型森林类型,对区域生态环境建设与经济持续发展具有重要作用。研究以冀北黑龙山的杨桦次生林为例,利用角尺度、混交度及大小比数以及参数熵权修正层次分析法,对中龄林与幼龄林的结构及森林自然度进行比较分析。结果表明:幼龄林与中龄林的树种组成均较单一,中龄林的树种多样性指数较高,树种组成较好;中龄林的直径分布范围较大,林木个体分化程度明显;幼龄林与中龄林的树高结构均呈单峰型,幼龄林树高分布范围较小,林层分化不明显;幼龄林与中龄林的林分角尺度都呈聚集分布,但中龄林林木个体分布较趋于随机;中龄林与幼龄林均以零度混交比例为主,中龄林的林分整体混交度相对较好;幼龄林与中龄林林分大小比数分化差异不明显,林分不同大小比数分布频率较均匀。幼龄林森林自然度等级为4,属于乡土树种混交林状态,中龄林森林自然度等级为5,属于次生林状态。%Secondary poplar-birch forest is a typical forest type in mountain area of north Hebei, and plays an important role in ecological construction and economic development of the region. Secondary poplar-birch forest in Heilongshan, mountain area of north Hebei was studied, comparative analysis about structure and naturalness were conducted in the middle-aged forest and young forest, and three parame-ters-angle index, neighborhood comparison, mingling and entropy weight AHP-were used. The results show that the species composition of young forest and middle-aged forest were single, tree species diversity of middle-aged forest was higher, species composition was better;The diameter distribution range of middle-aged forest was larger, individual differentiation was obvious;The tree height structure of young forest and middle-aged forest both showed single peak type, the height distribution

  2. Compatible Tree Biomass Models for Natural White Birch (Betula platyphylla) in Northeast China Forest Area%东北林区天然白桦相容性生物量模型

    Institute of Scientific and Technical Information of China (English)

    董利虎; 李凤日; 贾炜玮

    2013-01-01

    基于东北林区天然白桦实测生物量数据,通过2种方案(以总生物量为基础分级控制和以总生物量为基础直接控制)建立天然白桦一元和二元相容性生物量模型,模型参数估计采用非线性度量误差联立方程组估计方法,并采用加权回归的方法进行异方差的消除.结果表明:2种方案所建立的天然白桦一元、二元相容性生物量模型的确定系数R2 =0.800~0.988,模拟效率(EF) =0.80~0.97;2种方案所建立的相容性生物量模型的预测精度大多数在80%以上,树枝和树叶生物量模型的预测精度较差,但也在69%以上;所建立的相容性生物量模型中,总生物量和树干生物量模型效果较好,树根、树叶和树枝生物量模型效果较差.总的来说,2种方案所建立的相容性生物量模型都具有一定的精度,都能对天然白桦生物量进行很好的预估,以总生物量为基础直接控制方案所建立的一元和二元相容性生物量模型好于以总生物量为基础分级控制方案所建立的一元和二元相容性生物量模型,所以在进行天然白桦生物量预估时,建议采用以总生物量为基础直接控制所建立的相容性生物量模型.%Based on data of tree biomass for natural white birch (Betula platyphylla) in northeast China forest area,two methods (controlling jointly from level to level and controlling directly under total biomass) were used to establish the mono-element and dual-element compatible tree biomass model of natural white birch.And using nonlinear measurement error simultaneous equation estimated the parameters in the model,at the same time,the weighted regression was used to eliminate the heteroscedasticity.The results showed that R2 of mono-element and dual-element compatible model in this paper was 0.800-0.988,and the fit efficiency (EF) was 0.80-0.97.Besides,the precision of these models reached beyond 80%.On the other hand,the precision of foliage and

  3. 庞泉沟地区山地杨桦林优势种种群格局与动态%POPULATION PATTERN AND DYNAMICS OF MOUNTAINOUS POPLAR-BIRCH FOREST IN PANGQUANGOU NATURAL RESERVE

    Institute of Scientific and Technical Information of China (English)

    田世广; 张金屯; 张钦弟; 张斌; 苏日古嘎

    2011-01-01

    Dynamic changes of forest communities in various stages are shown as the dominant population growth and demise and changes of competitive strength, this change trend can be effectively described by size structure and pattern analysis. The paper studies characteristics of dynamic change in the mountain poplar-birch in the Pangquangou National Nature Reserve. and results show that Populus trernula and Betula platyphylla and Picea wilsonii are clumped within a certain scale, Populus tremula, and Picea wilsonii occupy similar habitat. Picea wilsonii own notable advantage in the competition, and will replace Populus tremula in the succession. For population change in the community is relative stable Betula platyphylla and Betula albosinensis, long-presence, and possible form broadleaf-coniferous forest mixed forest together with Picea wilsonii.%森林群落的动态变化在各个阶段表现为优势种群数量增长和消亡及竞争强弱的变化,径级结构和格局分析能有效地描述这种变化的趋势.本文研究庞泉沟自然保护区山地杨桦林这种变化特征,结果表明群落变化过程中,一定尺度范围内的山杨、白桦、青杆在小尺度上均为集群分布,在大尺度上趋于随机分布.山杨和青杆呈明显正相关关系,占据相似的生境,青杆在竞争中占有优势,在演替过程中将取代山杨.白桦和红桦在群落变化过程中较为稳定,在演替中可能将长期存在,与青杆形成针-阔叶混交林.

  4. Study on preparation and properties of birch fibre/unsaturated polyester composite%桦木纤维/不饱和聚酯复合材料制备与性能研究

    Institute of Scientific and Technical Information of China (English)

    胡忠勤; 李红媛; 陈楚航; 刘文广; 刘智; 张秀成

    2011-01-01

    采用硅烷偶联剂、乙醇和水等分别对桦木纤维(BF)和回收纸浆纤维进行表面处理,并分别将改性纤维作为不饱和聚酯树脂(UPR)的增强材料,制备相应的BF/UPR复合材料.研究了不同改性方法对复合材料界面性能的影响.结果表明:不同纤维种类、不同纤维表面处理方法和不同纤维用量对复合材料的界面性能、力学性能等影响较大;经硅烷偶联剂处理后的BF,可有效改善BF与UPR之间的界面相容性;当w(偶联剂处理BF)=16%时,相应复合材料的拉伸强度和冲击强度比纯UPR体系分别提高了31.0%和28.5%;在制备回收纤维/UPR复合材料之前应先对回收材料进行筛选,并且应优先选择对UPR基体树脂具有明显增强作用的回收纤维.%The surfaces of birch fibres(BF) and reclaimed pulp fibres were treated by some materials such as silane coupler,ethanol and water respectively,then the relevant BF/UPR(unsaturated polyester resin) composites were prepared with these modified fibres as reinforcing materials of UPR. The influences of different modified methods on interface properties of composites were investigated. The results showed that the influences of different kinds of fibres,different surface treatment methods for fibres and different fibres contents on interface properties and mechanics properties for composites were more great. The BF treated by silane coupler could effectively improve the interface compatibility between BF and UPR. The tensile strength and impact strength of relevant composite were 31.0% and 28.5% more than those of pure UPR system when the mass fraction of BF treated by coupler was 16%. The reclaimed materials should first be screened before preparing reclaimed fibre/UPR composite,and the reclaimed fibres,which could obvious reinforce UPR matrix resin ,should be preferred.

  5. Long-term Management Effect of of Poplar-birch Secondary Forest%杨桦中幼天然次生林的长期经营效果

    Institute of Scientific and Technical Information of China (English)

    魏彪; 周冬跃; 戴福; 陆莹; 王庆斌; 付静; 祝旭加

    2014-01-01

    采取固定标准地和临时标准地相结合的调查方法,调查了试验地林分树种组成、树高、胸径、径阶分布、空间结构状况,分析了林冠下引进红松促进杨桦天然次生林更新的试验效果。结果证明:林冠下引进红松促进杨桦天然次生林更新技术,不但改变了林分树种组成,而且改善了林木分布,提高了林木生长速度,增加了林分蓄积。林冠下引进红松幼苗,在未显著改变次生林林木混交度的情况下,27 a试验林分林木分布,从团状改善为随机分布;红松优势度得到提高,从处于中庸和劣势之间,提高到介于中庸和亚优势之间;试验样地蓄积得到提高,和对照相比蓄积提高72%。%An experiment was conducted to study the long-term effect of planting Korean pine on accelerating the succession of poplar-birch secondary forest includingtree composition, height,diameter at breast height, diameter class and distribution by establishing fixed and temporary sample plots.This technique not only changed the composition of tree species, but also improved the tree distribution between different diameter class, and the growth and the volume were accelerated.In the past 27 years, the distribution changed from reunion to random under the condition that the mingling index unchanged re-markable.The dominance of Korean pine was improved and the stock of the stand was improved 72%than the CK stand.

  6. Ground bryophyte diversity in secondary birch forests in western Sichuan, China%亚高山次生桦木林地表苔藓组成与多样性

    Institute of Scientific and Technical Information of China (English)

    闫晓丽; 包维楷

    2011-01-01

    桦木林(Betula spp.)是我国原始冷杉林(Abies spp.)皆伐后自然恢复形成的主要次生林之一,为揭示其发育过程中地表苔藓组成与多样性差异,评估其自然恢复状况,我们选择了四川省金川县507林场地形条件基本一致的3个桦木林地以及1个原始岷江冷杉(Abies faxoniana)林地,调查了地表苔藓层结构和物种组成.结果显示:(1)桦木林的地表苔藓植物盖度低于原始林,不同年龄的桦木林之间其盖度没有差异(P>0.05),但优势种的组成差异及物种替代明显;(2)桦木林地表苔藓物种丰富度较原始林高,不同年龄相比,9年生和22年生较42年生桦木林地表苔藓种类丰富;(3)未郁闭桦木林(9年生)与郁闭林(22年生和42年生)间的地表苔藓物种组成相似程度(相似性系数为0.24-0.29)低于它与原始林间的相似程度(0.51);22年生和42年生桦木林间地表苔藓物种组成相似程度(相似性系数为0.50)高于它们与原始林间的相似性程度(0.13-0.24),在自然恢复过程中,桦木林与原始林下地表苔藓共有种数量逐渐减少,相似程度降低.原始林下35种地表苔藓植物中只有25种存在于迹地桦木林地.上述分析表明:迹地上自然恢复9-42年的桦木林下地表苔藓多样性虽然较云杉人工林高,但仅保存约70%的原始林下种类,而约有29%的敏感苔藓种类无法通过次生林自然恢复过程得以保育或恢复.%Secondary birch (Betula spp.) forest is an important vegetation type in western Sichuan, China.These forests have naturally regenerated from primary fir (Abies spp.) forests after clear-cutting. However,little is known about ground bryophyte species composition and community structure during this succession sequence. In our study, we sampled three plots in 9-, 22-, and 42-year old secondary forests, and a primary fir forest, respectively, in Jinchuan County. We found that bryophyte coverage in different aged secondary forests was

  7. The Banyan and the Birch Tree

    DEFF Research Database (Denmark)

    Lorenzen, Mark; Taeube, Florian A.

    of embedded and arm's-length ties. We present novel data self-collected in qualitative, inductive fieldwork from more than 50 interviews in mainstream film production in Bollywood. Our findings contrast with extant research by showing that in the socio-cultural context of India the use of embedded ties...

  8. 长白山次生杨桦林树木短期死亡动态%Short-term death dynamics of trees in natural secondary poplar-birch forest in Changbai Mountains of Northeast China.

    Institute of Scientific and Technical Information of China (English)

    张昭臣; 郝占庆; 叶吉; 蔺菲; 原作强; 邢丁亮; 师帅; 王绪高

    2013-01-01

    Taking the 5 hm2 sampling plot in the natural secondary poplar-birch forest in Changbai Mountains as test object, and based on the two census data in 2005 and 2010, an analysis was made on the main tree species composition and quantity, size class distribution of dead individuals, and regeneration characteristics of .the main tree species in different habitat types of the plot in 2005-2010. In the five years, the species number of the individuals with DBH≥1 cm increased from 46 to 47, among which, 3 species were newly appeared, and 2 species were disappeared. The number of the individuals changed from 16509 to 15027, among which, 2150 individuals died, accounting for 13% of the whole individuals in 2005, and 668 individuals were newly increased. The basal area of the trees increased from 28. 79 m2 ·m-2 to 30. 55 m2·m-2, with that of 41 species increased while that of 6 species decreased. The decrease of the basal area of Betula platyphylla and Populus davidiana accounted for 72.3% of the total decrease. Small individuals had higher mortality, as compared with large ones, and the mortality of the individuals with DBH<5 cm occupied 65% of the total. B. platyphylla and P. davidiana contributed most in the dead individuals with large DBH. No difference was observed in the tree mortality among different habitat types, but the mortality of the individuals widi different size classes showed greater variation.%以长白山次生杨桦林5 hm2样地为对象,以2005和2010年两次调查数据为基础资料,分析了2005-2010年间样地主要树种的组成、数量,死亡个体的径级分布,以及不同生境类型下主要树种的更新特征.结果表明:研究期间,样地内树木胸径(DBH)≥1 cm的独立个体的树种数由46种增至47种,新增3个树种,2个树种因仅有的一个个体死亡而消失;独立个体数由16509株减少为15027株,其中,死亡个体数2150株,占2005年个体总数的13%,新增个体数668株,净减少1482个个体

  9. 高温胁迫诱导对白桦悬浮细胞三萜积累及防御酶活性的影响%The Effects of High Temperature Stress on the Accumulation of Triterpenoid and the Activity of Defense Enzyme in the Suspension Cells of Birch

    Institute of Scientific and Technical Information of China (English)

    常志凯; 白祎杰; 董恒; 尹静; 詹亚光

    2015-01-01

    通过研究不同高温胁迫下白桦细胞的细胞活力,防御酶活性和总三萜含量的变化,确定诱导白桦细胞合成三萜的最适高温胁迫条件。35℃、40℃、45℃、50℃和55℃胁迫白桦细胞1、2和4 h,测定其细胞活力,防御酶(SOD、CAT和PAL)活性和总三萜含量。结果显示,45-55℃高温胁迫下,细胞活力显著下降,以50℃2 h处理下降最显著,是对照细胞活力的6.8%;SOD和PAL活性显著增加,以55℃4 h处理后24 h时SOD和PAL活性最高,分别较对照提高164.9%和159.6%;CAT活性受到抑制,以55℃2 h和4 h处理在12 h后取样最低。50℃处理2 h后24 h取样,细胞总三萜含量最高,浓度为76.66 mg/g,比对照提高105.6%。最终确定50℃胁迫2 h后24 h取样为利用高温胁迫诱导白桦悬浮细胞合成三萜类物质的最适温度胁迫条件。%This work aims to study how the high temperature stress affects the cell vitality, the activity of defense enzyme and the contents of total triterpenoid in the suspension culture cells of birch, and determine the optimal heat stress treatment by which birch cells can be induced to synthesize triterpenoid. We set temperature of 35℃, 40℃, 45℃, 50℃and 55℃treating birch cells for 1, 2 and 4 h respectively, then measured the cells’vitalities, the activities of defense enzymes’(SOD, CAT and PAL), and the contents of total triterpenoid. Under the treatments of 45-55℃, cell’s vitality reduced significantly, and at 50℃for 2 h was only 6.8%of the control group;meanwhile, the activities of SOD and PAL increased significantly and reached the highest while treated at 55℃for 4 h and measured at 24 h, i.e., they increased 164.9%and 159.6%compared to the control group. However, the CAT activity was strongly inhibited, in lowest while treated at 55℃for 2 h and 4 h and measured at 12 h. When treated at 50℃for 2 h and sampled at 24 h, the contents of total triterpenoid were the

  10. The Effect of Sodium Nitrite and Arginine on the Biosynthesis of Nitric Oxide and Triterpenoid in Birch (Betula platyphylla Suk) Suspension Cells%亚硝酸钠和精氨酸对白桦悬浮细胞中NO和三萜合成的影响

    Institute of Scientific and Technical Information of China (English)

    许道琦; 张杰琨; 王晓东; 詹亚光; 范桂枝

    2012-01-01

    The aim was to analyze the relation of nitric oxide (NO) and triterpenoid production. Sodium nitrite and arginine were added in the eight-day-old birch suspension cell culture, the change of triterpene content and NO content were analyzed by chemical colorimetry and fluorescence microscopy. NO and triterpenoid content were increased by 500 μg/L and 100 μg/L sodium nitrite and arginine, and the higher increasing was induced by 500 μg/L sodium nitrite and arginine. The content of NO and triterpenoid in birch cells induced by 500 μg/L sodium nitrite was higher than that of 500 μg/L arginine, the increasing rate of triterpenoid was 1.5 times. Inhibitor of NaN3 and L-NAME decreased the effect of sodium nitrite and arginine on the biosynthesis of NO and triterpenoid, the content of NO and triterpenoid were near to the level of control. These results preliminary indicated that NR and NOS were involved in triterpenoids biosynthesis in birch suspension culture, and NR might be play an important role in triterpenoids biosynthesis.%旨在分析亚硝酸钠和精氨酸处理12h后白桦悬浮细胞中一氧化氮(NO)和三萜含量的变化.在白桦悬浮细胞的生长末期添加硝酸还原酶(NR)和一氧化氮合成酶(NOS)的底物亚硝酸钠和精氨酸,采用比色法和荧光显微镜方法分析白桦悬浮体系中三萜含量和NO含量的变化.500 μg/L和100 μg/L的亚硝酸钠和精氨酸均促进了白桦悬浮细胞中NO和三萜的合成,其中500μg/L的亚硝酸钠和精氨酸促进作用最强.500μg/L亚硝酸钠处理下白桦细胞中的NO荧光强度和三萜含量均高于500μg/L精氨酸处理,其中三萜含量增加了1.5倍.将NR和NOS的抑制剂NaN3和L-NAME分别添加到亚硝酸钠和精氨酸处理的白桦悬浮体系中,发现亚硝酸钠和精氨酸对NO和三萜合成的促进作用被抑制了.NR和NOS来源途径的NO参与了白桦三萜的合成,可能NR来源途径的贡献大于NOS途径.

  11. 燕山北部山地人工落叶松林与天然次生林物种多样性的比较%Biodiversity between larch plantation and secondary poplar- birch forest in north region of Yanshan mountain

    Institute of Scientific and Technical Information of China (English)

    纪晓林; 贾彦龙; 卢金平; 李倩茹; 许中旗

    2011-01-01

    In order to understand the biodiversity maintain function of Larch plantation, taking 13 - year, 30 - year Larch plantation and 13 - year,28 - year secondary poplar- birch forest as research object,the biodiversity between them and the effects of thinning on Larch plantation biodiversity were investigated. Results showed that biodiversities in Larch plantation had no significant differences with secondary poplar - birch forest except Simpson Index and Shannon - weiner Index of 30 -year Larch plantation. Thinning mainly reduced the diversity of tree layer in short time, but it had no significant effect on shrub and herb layer. Larch plantation in north region of Yanshan mountain could maintain high biodiversity.%为了解燕山北部山地华北落叶松人工林植被物种多样性维持功能的高低,选取13 a和30a生人工落叶松林,以13 a和28a生天然次生杨桦林作为对照,对两种林分的植被多样性进行调查和分析,并研究了间伐对人工落叶松林植被物种多样性的影响.结果表明,林龄相同或相近的两种林分类型相比,无论是乔木层、灌木层或是草本层,人工落叶松林丰富度、Simpson指数、Shannon- Weiner指数均表现出相当或略高于天然次生杨桦林(30a生人工落叶松林乔木层多样性指数除外);间伐对人工落叶松林植被物种多样性的短期影响主要体现在乔木层,对林下灌木层和草本层无明显影响.燕山北部山地人工落叶松林具有较高的植物多样性维持功能,没有导致物种多样性的降低.

  12. 燕山北部华北落叶松人工林与杨桦天然次生林土壤碳密度的比较%Soil carbon content comparison between larch plantation and secondary poplar-birch forest in Northern Region of Yanshan Mountains

    Institute of Scientific and Technical Information of China (English)

    王艳军; 徐国巧; 李亚男; 贾彦龙; 许中旗

    2014-01-01

    Soil organic carbon content (SOCC) of larch plantation and natural secondary pop-lar-birch forest in west region of Yanshan Mountains was studied in this paper for under-standing the effects of afforestation over soil organic carbon stock .The results showed that SOCC of larch plantation ( 30 .45 g/kg ) was higher than that of secondary poplar-birch forest ( 28 .45 g/kg ) .The SOCC of the both forests decreased with the soil depth .At the same time ,there was significant difference of SOCC between adjacent layers in upper soil but not in lower soil by variance analysis .It was concluded that under proper afforestation meas-ures and less human disturbance ,the plantation could maintain high soil organic carbon stock as natural forests .%为了了解人工造林过程对土壤碳储量的影响,对燕山西部山地常见的华北落叶松人工林和杨桦天然次生林土壤有机碳含量进行了研究。结果表明,华北落叶松人工林和杨桦天然次生林的土壤剖面平均有机碳含量分别为30.45 g/kg和28.45 g/kg ,二者没有明显差异;2种林分的土壤有机碳含量均随着土层深度的增加而降低,下降幅度则随深度的增加逐渐减缓,表层土壤对土壤的碳存储贡献更大。总的来看,土壤有机碳含量在深层(30 cm以下)相邻土层之间差异不显著,说明深层土壤中,有机碳含量变化较小。由以上结果可以得出结论,在造林措施适当、人为干扰较少的条件下,人工林同样可以维持与天然林相近的较高的土壤碳储量。

  13. Plant Functional Types and Their Impact Environmental Factors in a Naturally Recovered Poplar-birch Woodland on the North Slope of Qilian Mountains, China%祁连山北坡自然恢复杨桦林地植物功能型组成及其影响因素

    Institute of Scientific and Technical Information of China (English)

    石福习; 赵成章; 任珩; 周伟; 高福元; 盛亚萍; 李丽丽

    2012-01-01

    Plant functional types (PFTs) are important in understanding the dynamics and the functions of an ecosystems, which provide also useful information for ecosystem management. In 28 observation plots of a naturally recovered popiar-birch woodland on the north slope of Qilian Mountains, China, 81 plant species were classified into 18 plant functional types (PFTs), according to their life forms (including arbors, lianas, subshrub, shrub, perennial grasses, perennial forbs and annual or biennial grass) and ecotypes (including xerophyte, xerophytic and mesophytic, mesophyte and hygrophyte). The relationships between PFTs and environmental factors were studied using Canonical Correspondence Analysis (CCA). The results showed that the dominant PFTs were PFTsl6 (mesophytic perennial forbs), PFTs23 (hygrophytic perennial forbs), PFTs9 (xerophytic and mesophytic perennial forbs) and PFTslS (mesophytic shrub) on the poplar-birch restoration woodland. The stratificd structure with wood, shrub and herb layers indicated the plant life forms had a tendency of complication and structurization, and the emerging mesophyte plants reflected changes of the micro-environments. The distribution patterns of PFTs were controlled by the soil physical and chemical properties in that soil bulk density, soil organic carbon and content of nitrogen determined the characteristics of the plant life forms, while the soil water moisture and canopy cover were the main ecologis factors that affected the distribution of ecotypes. The slope position and slope aspect controlled the plant distribution pattem and formation of the community.%依据生活型(乔木、藤本、灌木、半灌木、多年生禾草、多年生杂类草和一二年生草本)和水分生态型(旱生、旱中生、中生和湿生)将祁连山北坡次生杨桦林28个调查样地中的81个物种划分为18种植物功能型(Plant function types,PFTs),并通过典范对应分析(CCA)方法研究植物功能型与环境因子间

  14. Onset of oral allergic syndrome during birch sublingual immunotherapy.

    Science.gov (United States)

    Ciprandi, G

    2012-08-01

    Pollen allergy may be frequently associated with oral allergy to fruits and/or vegetables (the so called oral allergic syndrome). Some studies reported a possible positive effect exerted by allergen-specific immunotherapy on OAS course, while others did not. A case of OAS case onset after starting sublingual immunotherapy is reported.

  15. Connolly Hospital (Silver Birch & Woodland Units), Blanchardstown, Dublin 15.

    LENUS (Irish Health Repository)

    Strik, Caroline M

    2010-05-24

    Abstract Background High fat diets have long been associated with weight gain and obesity, and the weak satiety response elicited in response to dietary lipids is likely to play a role. Suppression of appetite and food intake has consistently been shown to be diminished with high fat relative to either high protein or carbohydrate meals. There is however some evidence that the satiating capacity of lipids may be modulated when physicochemical properties are altered, but studies investigating the effect of lipid saturation on appetite have generated inconsistent findings. This study investigated the effects of changes in fatty acid saturation on post-ingestive satiety and energy intake. Methods High-fat (HF) test breakfasts (2.0 MJ) containing 26 g lipid were given to 18 healthy, lean men in a 3 treatment randomised cross-over design, each treatment separated by a washout of at least 3 days. The breakfasts were high in saturated (SFA, 65% of total fat), polyunsaturated (PUFA, 76%) or monounsaturated (MUFA, 76%) fatty acids, and comprised 2 savoury muffins. Participants rated appetite sensations using visual analogue scales (VAS) to assess palatability immediately following the meals, and hunger and fullness prior to the HF breakfast and throughout the day. Energy intake was measured by covert weighing of a lunch meal which was served 3.5 h after the breakfast, and from which the participants ate ad libitum. Results There was no difference in VAS ratings of pleasantness, visual appearance, smell, taste, aftertaste and overall palatability between the 3 high-fat test breakfasts. However, there was also no differential effect of the 3 treatments on ratings of hunger, fullness, satisfaction or prospective food consumption during the 3.5 h following the breakfast meal and over the full 6 h experiment. Energy and macronutrient intake at lunch also did not differ between treatments (mean, sem; SFA: 5275.9 ± 286.5 kJ; PUFA: 5227.7 ± 403.9 kJ; MUFA: 5215.6 ± 329.5 kJ; P > 0.05). The maximum difference in energy intake between treatments was less than 2%. Conclusions There was no evidence of a difference in post-ingestion satiety between high fat meals which differed in saturation profile in this group of lean, healthy men. Trial Registration ACTRN12610000193077

  16. Genetic relationship of interspecies for eight birch species

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Genetic relationships of eight species of genus Betula were evaluatedusing ISSR marks. A total of 236 loci were generated from 17 ISSR primers. Perce ntage of polymorphic bands (PPB) varied from 5.93 to 19.92. The highest and the lowest level of genetic differentiation were detected in B. Ovalifolia and B. Ma ximowicziana Regel respectively. In these eight species, genetic diversity of bi rch (HT) was 24.38 %, and the genetic variation (GST ) interspecies was accounti ng for 79.36% of total genetic variation. According to the cluster results of ge netic distance, the eight species were classified into three groups as B. Davur ica, B. Ovalifolia, B. Platyphylla and B. Pendula for one group;B. Schmidtii, B . Costata and B. Ermanii Cham. Var. Communis for one group, and B. Maximowiczian a Regel for another group. The result of cluster is consistent with traditional morphological classification.

  17. Connolly Hospital (Silver Birch & Woodland Units), Blanchardstown, Dublin 15.

    LENUS (Irish Health Repository)

    Hegerl, Ulrich

    2009-01-01

    BACKGROUND: Suicide and non-fatal suicidal behaviour are significant public health issues in Europe requiring effective preventive interventions. However, the evidence for effective preventive strategies is scarce. The protocol of a European research project to develop an optimized evidence based program for suicide prevention is presented. METHOD: The groundwork for this research has been established by a regional community based intervention for suicide prevention that focuses on improving awareness and care for depression performed within the European Alliance Against Depression (EAAD). The EAAD intervention consists of (1) training sessions and practice support for primary care physicians,(2) public relations activities and mass media campaigns, (3) training sessions for community facilitators who serve as gatekeepers for depressed and suicidal persons in the community and treatment and (4) outreach and support for high risk and self-help groups (e.g. helplines). The intervention has been shown to be effective in reducing suicidal behaviour in an earlier study, the Nuremberg Alliance Against Depression. In the context of the current research project described in this paper (OSPI-Europe) the EAAD model is enhanced by other evidence based interventions and implemented simultaneously and in standardised way in four regions in Ireland, Portugal, Hungary and Germany. The enhanced intervention will be evaluated using a prospective controlled design with the primary outcomes being composite suicidal acts (fatal and non-fatal), and with intermediate outcomes being the effect of training programs, changes in public attitudes, guideline-consistent media reporting. In addition an analysis of the economic costs and consequences will be undertaken, while a process evaluation will monitor implementation of the interventions within the different regions with varying organisational and healthcare contexts. DISCUSSION: This multi-centre research seeks to overcome major challenges of field research in suicide prevention. It pools data from four European regions, considerably increasing the study sample, which will be close to one million. In addition, the study will gather important information concerning the potential to transfer this multilevel program to other health care systems. The results of this research will provide a basis for developing an evidence-based, efficient concept for suicide prevention for EU-member states.

  18. 温度对桦木单板表面化学镀 Ni-Cu-P三元合金的影响%Effect of Temperature on Electrlo se s Deposition of Ni-Cu-P Ternary Alloy on Birch Veneer

    Institute of Scientific and Technical Information of China (English)

    惠彬; 李坚; 王立娟

    2015-01-01

    利用化学镀方法在桦木单板表面沉积Ni—Cu—P三元合金,考查施镀温度对镀后单板表面电阻率和电磁屏蔽效能的影响,采用扫描电镜( SEM)观察镀后单板的表面形貌,利用EDS和 XPS分析镀层成分,利用X射线衍射( XRD)分析镀层的组织结构,采用直拉法测定镀层与木材表面的结合强度。结果表明:当温度从80℃升高到90℃时,镀层平均表面电阻率从0.451Ω/cm2降低至0.301Ω/cm2;继续升高温度,表面电阻率小幅升高;在90℃时,施镀单板的电磁屏蔽效能在9 kHz~1.5 GHz频段达到55~60dB 。 SEM观察发现镀层连续、致密且具有金属光泽;EDS分析可知镀层中存在Ni、Cu和P元素,XPS分析可知镀层组成为Ni、Cu、P,其质量分数分别为79.84%、11.82%和8.34%;XRD分析表明镀层为微晶态结构;镀层与木材表面结合牢固。%We used electroless plating to deposite Ni-Cu-P ternary alloy on birch veneer to study the effects of plating tempera-ture on surface resistivity and electromagnetic shielding effectiveness.We observed the surface morphology of plated veneer by scanning electron microscopy ( SEM), and analyzed the composition of the coating by energy dispersion spectrometer ( EDS) ,X -ray photoelectron spectroscopy ( XPS) and the structure of the coating by X-ray diffraction ( XRD) .We meas-ured the bonding strength between the coating and wood surface by vertical pulling method.The mean surface resistivity de-creased from 0.451Ω/cm2 to 0.301Ω/cm2 with increasing temperature from 80℃to 90℃.However, the surface resistivity increased slightly with further increasing temperature.The electromagnetic shielding effectiveness of plated veneer was up to 55-60 dB in frequencies range of 9-1.5 GHz at 90℃.By SEM, the coating was smooth, continuous and compact, and had metallic sheen.By EDS, the coating was composed of nickel, copper and phosphorus element.By XPS

  19. Effect of Induced Transformation on Soil Respiration of White Birch Low-Quality Forest in Daxing’ an Moun-tain%诱导改造对大兴安岭白桦低质林土壤呼吸的影响

    Institute of Scientific and Technical Information of China (English)

    曾翔亮; 董希斌; 宋启亮

    2013-01-01

    对大兴安岭白桦低质林以不同带宽(6、10、14、18 m)进行皆伐后,种植樟子松进行诱导改造,采用LI-8150多通道土壤碳通量自动测量系统对各诱导改造带以及对照样地的土壤呼吸进行试验分析。结果表明:白桦低质林诱导改造后土壤呼吸的日平均值和日变化幅度均高于对照样地;各诱导改造带的温度敏感指数( Q10)值在2.25~5.53,总体趋势是随着带宽的增加Q10值升高,但与对照样地(Q10=5.99)相比,均有不同程度的降低;各诱导改造带土壤呼吸的最适含水率在17.33%~19.11%,均低于对照样地的最适含水率(19.43%),且随着带宽增加,最适含水率降低;土壤呼吸受土壤温度和湿度的共同影响,但土壤温度比土壤湿度更能显著影响土壤呼吸,双因素模型优于仅考虑土壤温度或土壤湿度的单因素模型。%Clear-cutting was executed in white birch low-quality forest of Daxing’an Mountain with different bandwidth (6 m, 10 m, 14 m and 18 m) , the induced transformation was performed by planting Pinus sywestris var.mongovica Litvin, and LI-8150 multi-channel soil carbon flux automatic measuring system was used to test and analysis the induced transformation zone and the check zone.Daily average value and variation range of soil respiration in the induced transformation zone are higher than that in the check zone.Q10 in the induced transformation zone is between 2.25 and 5.53, and the overall trend is: Q10 increases with the increasing of the bandwidth of induced transformation, but they are lower than those in the check zone (5.99) in different degrees.The optimum moisture content of soil respiration in the induction transformation zone is between 17.33%and 19.11%, less than that in the check zone (19.43%).With the increasing of the bandwidth, the optimum moisture content decreases.The soil respiration is influenced by soil temperature and

  20. 大兴安岭白桦低质林皆伐改造后枯落物水文效应%Hydrological Effect of Birch Coppice Low-Quality Forest Litter after Clear-cutting Transformation in Daxing’ an Mountains

    Institute of Scientific and Technical Information of China (English)

    李超; 董希斌; 宋启亮

    2013-01-01

    对大兴安岭地区白桦低质林进行不同带宽的带状和不同面积的块状两种不同皆伐方式的改造后枯落物水文效应变化的研究。结果表明:带宽为6~18 m的皆伐带未分解层枯落物蓄积量所占比例均小于半分解层的枯落物蓄积量,面积为5 m×5 m~30 m×30 m的块状区域未分解层枯落物蓄积量所占比例和半分解层比较大小不一;枯落物蓄积量排序:带状皆伐8.67 t/hm2>块状皆伐4.41 t/hm2。每条带宽的皆伐带未分解层的最大持水量所占比例均小于半分解层的最大持水量,每个面积的块状区域未分解层的最大持水量所占比例和半分解层比较大小不一;枯落物最大持水量排序:块状皆伐35.44 t/hm2>带状皆伐14.23 t/hm2。每条皆伐带未分解层枯落物有效拦蓄量所占比例均小于半分解层的枯落物有效拦蓄量,每个面积的块状区域未分解层的有效拦蓄量所占比例和半分解层比较大小不一;枯落物有效拦蓄量排序:带状皆伐25.17 t/hm2>块状皆伐7.81 t/hm2。带状和块状皆伐方式下,枯落物持水量与浸泡时间的关系均呈现对数关系上升,而枯落物吸水速率与浸泡时间的关系均呈现乘幂关系下降。%The experiment was conducted to study the hydrological effect of falling object in Daxing’an Mountains of birch cop-pice low-quality forest in different bandwidth and different area by two different clear cuttings.The litter proportion volume in not decomposition level is less than that of the half decomposition level in bandwidth for 6 m-18 m clear cutting band. While litter proportion volume in no decomposition level has no significant relationship with the half decomposition level in the area of 5 m×5 m-30 m×30 m.The volume of litter shows band clear cutting 8.67 t/hm2>area clear cutting 4.41 t/hm2 .Water holding capacity in no decomposition layers of the largest proportion is less than that

  1. Hormesis and Paradoxical Effects of Drooping Birch (Betula pendula Roth Parameters Under Motor Traffic Pollution

    Directory of Open Access Journals (Sweden)

    Elena A. Erofeeva

    2015-06-01

    Full Text Available Various plant indexes are used or recommended for bioindication. However, the nonmonotonic dose–response dependences (hormesis and paradoxical effects of these indexes are insufficiently explored upon exposure to pollution. We studied the dependences of these Betula pendula indexes on the intensity of motor traffic pollution. Regression analysis did not reveal any dependence of chlorophyll and carotenoid content on traffic intensity (in 2008 and 2010-2013. Lipid peroxidation rate had different versions of paradoxical effects in 2008 and 2010 to 2012 and increased in comparison with control under an increase in pollution level in 2013. In 2010 to 2012, all dose–response dependences for total protein and thiol group content were biphasic and multiphasic paradoxical effects. In 2013, an increase in traffic intensity induced a linear reduction in protein content and an increase in thiol group level in comparison with the control. In most cases, the studied phenological indexes and seed production decreased monotonically in comparison with the control following an increase in traffic intensity. Only in 2010 and 2013, share of fallen leaves had hormesis and paradoxical effect accordingly. Fluctuating asymmetry had a paradoxical effect and hormesis in 2008 and 2012, accordingly, and increased in comparison with the control under an increase in the level of pollution in 2010 to 2011.

  2. Hormesis and Paradoxical Effects of Drooping Birch (Betula pendula Roth) Parameters Under Motor Traffic Pollution.

    Science.gov (United States)

    Erofeeva, Elena A

    2015-01-01

    Various plant indexes are used or recommended for bioindication. However, the nonmonotonic dose-response dependences (hormesis and paradoxical effects) of these indexes are insufficiently explored upon exposure to pollution. We studied the dependences of these Betula pendula indexes on the intensity of motor traffic pollution. Regression analysis did not reveal any dependence of chlorophyll and carotenoid content on traffic intensity (in 2008 and 2010-2013). Lipid peroxidation rate had different versions of paradoxical effects in 2008 and 2010 to 2012 and increased in comparison with control under an increase in pollution level in 2013. In 2010 to 2012, all dose-response dependences for total protein and thiol group content were biphasic and multiphasic paradoxical effects. In 2013, an increase in traffic intensity induced a linear reduction in protein content and an increase in thiol group level in comparison with the control. In most cases, the studied phenological indexes and seed production decreased monotonically in comparison with the control following an increase in traffic intensity. Only in 2010 and 2013, share of fallen leaves had hormesis and paradoxical effect accordingly. Fluctuating asymmetry had a paradoxical effect and hormesis in 2008 and 2012, accordingly, and increased in comparison with the control under an increase in the level of pollution in 2010 to 2011.

  3. Simulated browsing affects leaf shedding phenology and litter quality of oak and birch saplings.

    Science.gov (United States)

    Palacio, S; Hester, A J; Maestro, M; Millard, P

    2013-04-01

    Herbivore effects on leaf litter can have a strong impact on ecosystem nutrient cycling. Although such effects are well described for insect herbivory, research on the impacts of browsing by mammalian herbivores on leaf litter dynamics and nutrient cycling has been more limited, particularly at the level of the individual plant. Clipping treatments (66% shoot removal twice, plus unclipped) were applied to analyse the effect of browsing on the phenology (start date and pattern of leaf shedding) and leaf litter quality (nitrogen (N), soluble sugars, starch and total non-structural carbohydrate concentrations, plus C : N ratios) of Betula pubescens Ehrh. and Quercus petraea [Matt.] Liebl. saplings. Clipping decreased leaf litter biomass and delayed leaf senescence and shedding, but did not change the phenological timing of litterfall between senescence and shedding. The quality of leaf litter of both species was increased by simulated browsing, through an increase in N and carbohydrate concentrations (mainly soluble sugars) and a decreased C : N ratio. This is the first evidence we are aware of that browsing may cause changes in leaf shedding phenology, delaying the process without altering its pattern. Our results also indicate that simulated browsing increases the quality of leaf litter. However, the potential positive effect of browsing on N cycling through litter quality may be offset by its negative impact on the amount of N shed per tree.

  4. Ecological interactions between herbivores and silver birch and aspen trees genetically modified for fungal disease resistance

    OpenAIRE

    Vihervuori , Liisa

    2015-01-01

    Many risks and environmental concerns have been linked with the cultivation of genetically modified (GM) trees. Among the most frequently mentioned risks are the unintentional/pleiotropic effects of transgenes on organisms or plant properties that are not the targets of genetic modification. Risks in forest ecosystems are difficult to predict, due to the long life cycles of trees and their complex ecological interactions. This thesis is focused on the interactions between insect and mammal he...

  5. Detection of Malware and Malicious Executables Using E-Birch Algorithm

    OpenAIRE

    Dr. Ashit Kumar Dutta

    2016-01-01

    Malware detection is one of the challenges to the modern computing world. Web mining is the subset of data mining used to provide solutions for complex problems. Web intelligence is the new hope for the field of computer science to bring solution for the malware detection. Web mining is the method of web intelligence to make web as an intelligent tool to combat malware and phishing websites. Generally, malware injected through websites into the user system and modifies the executable file and...

  6. Determining the age of young silver birch (Betula pendula Roth) trees growing on former agricultural

    OpenAIRE

    Tkaczyk, Miłosz; Tomusiak, Robert

    2013-01-01

    In Poland, according to the law (amendment of the act of 21st May 2010) – on the provision of information on the environment and its protection, public participation in environmental protection and environmental impact assessments etc. (Official Law Journal article 08.199.1227, as amended) – the owner can cut down trees without permission, if they do not exceed the age of 10 years old. However, if an owner happens to cuts down a tree on his property without knowing the age of the ...

  7. The Birch Street Irregulars: mysteries found and resolved in the AAVSO data archives

    Science.gov (United States)

    Beck, Sara J.; Saladyga, Michael; Mattei, Janet A.

    As they evaluate AAVSO data, AAVSO technical staff members run across several kinds of errors. This paper takes a humorous and Sherlock Holmes-style look at some of the most common kinds of errors detected, from observers recording the wrong Julian Date, misidentifying stars, transposing entries on the observer form, to garden-variety data entry errors.

  8. Mercury in Orange Birch Bolete Leccinum versipelle and soil substratum: bioconcentration by mushroom and probable dietary intake by consumers.

    Science.gov (United States)

    Krasińska, Grażyna; Falandysz, Jerzy

    2016-01-01

    The aim of this study was to examine the contamination, accumulation, and distribution of mercury in fruiting bodies by Leccinum versipelle fungus collected from distant sites across Poland. Mercury was determined using validated method by cold-vapor atomic absorption spectroscopy after direct sample matrix combustion. A large set of data gained using 371 fruiting bodies and 204 soil samples revealed the susceptibility of L. versipelle to Hg contamination and permitted the estimation of probable intake of Hg contaminant by consumers foraging for this species. The range of median values of Hg determined in caps of L. versipelle was from 0.20 to 2.0 mg kg(-1) dry biomass, and the median for 19 localities was 0.65 mg kg(-1) dry biomass. The values of the Hg bioconcentration factor (BCF) determined for L. versipelle correlated negatively with Hg contents. Mercury in topsoil beneath L. versipelle ranged from 0.019 to 0.041 mg kg(-1) dry matter for less-contaminated locations (BCF of 17 to 65 for caps) and from 0.076 to 0.39 mg kg(-1) dry matter for more contaminated locations (BCF of 1.9 to 22). Fruiting bodies of L. versipelle collected in some regions of Poland if consumed in amount of 300 g in one meal in a week could provide Hg doses above the provisionally tolerable weekly intake (PTWI) value of 0.004 mg Hg kg(-1) body mass, while regular consumptions for most of the locations were below the limit even with more frequent consumption. Also summarized are available data on Hg for three species of fungi of genus Leccinum foraged in Europe.

  9. Effect of wood ash on leaf and shoot anatomy, photosynthesis and carbohydrate concentrations in birch on a cutaway peatland.

    Science.gov (United States)

    Aguraijuja, Karin; Klõšeiko, Jaan; Ots, Katri; Lukjanova, Aljona

    2015-07-01

    Trees in cutaway peatland are growing in difficult conditions. Fertilization with nutrient-rich wood ash helps improve growth conditions. Photosynthesis and carbohydrate concentration along leaf anatomy were studied on plots treated with 10 and 5 t ha(-1) wood ash (WA10 and WA5) and on untreated (Control) plot to explain the physiological background of the differences in tree growth. The leaves from WA10 had the largest leaf area, total thickness, the thickest mesophyll and also significantly larger average values of all anatomical parameters of the shoots. The photosynthetic assimilation was significantly higher on treated plots at 200 and 400 ppm CO2 levels. In leaves on the treated plots, the sucrose concentration was lower while that of starch was higher than in trees on untreated soil. The differences in the maximum photosynthesis were relatively small. At unit ground, the leaf area provided for a wood ash-treated tree an efficient surface for CO2 assimilation, light interception and some starch storage during the growing period.

  10. EFFECT OF NITROGEN AND LIGHT ON NUTRIENT CONCENTRATIONS AND ASSOCIATED PHYSIOLOGICAL RESPONSES IN BIRCH AND FIR SEEDLINGS. (R826591)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  11. Damage Characterization of Bio and Green Polyethylene–Birch Composites under Creep and Cyclic Testing with Multivariable Acoustic Emissions

    Directory of Open Access Journals (Sweden)

    Alencar Bravo

    2015-11-01

    Full Text Available Despite the knowledge gained in recent years regarding the use of acoustic emissions (AEs in ecologically friendly, natural fiber-reinforced composites (including certain composites with bio-sourced matrices, there is still a knowledge gap in the understanding of the difference in damage behavior between green and biocomposites. Thus, this article investigates the behavior of two comparable green and biocomposites with tests that better reflect real-life applications, i.e., load-unloading and creep testing, to determine the evolution of the damage process. Comparing the mechanical results with the AE, it can be concluded that the addition of a coupling agent (CA markedly reduced the ratio of AE damage to mechanical damage. CA had an extremely beneficial effect on green composites because the Kaiser effect was dominant during cyclic testing. During the creep tests, the use of a CA also avoided the transition to new damaging phases in both composites. The long-term applications of PE green material must be chosen carefully because bio and green composites with similar properties exhibited different damage processes in tests such as cycling and creep that could not be previously understood using only monotonic testing.

  12. Is immunotherapy-induced birch-pollen-specific IgG4 a marker for decreased allergen-specific sensitivity?

    DEFF Research Database (Denmark)

    Bodtger, U; Ejrnaes, A M; Hummelshoj, L;

    2005-01-01

    The role of IgG4 during allergen-specific immunotherapy (SIT) is still controversial. The available studies present paramount differences in in vitro techniques, allergens, and clinical outcome parameters. By implementing a sensitive method, and pivotal clinical outcome parameters, we wanted to...

  13. Effect of wood ash on leaf and shoot anatomy, photosynthesis and carbohydrate concentrations in birch on a cutaway peatland.

    Science.gov (United States)

    Aguraijuja, Karin; Klõšeiko, Jaan; Ots, Katri; Lukjanova, Aljona

    2015-07-01

    Trees in cutaway peatland are growing in difficult conditions. Fertilization with nutrient-rich wood ash helps improve growth conditions. Photosynthesis and carbohydrate concentration along leaf anatomy were studied on plots treated with 10 and 5 t ha(-1) wood ash (WA10 and WA5) and on untreated (Control) plot to explain the physiological background of the differences in tree growth. The leaves from WA10 had the largest leaf area, total thickness, the thickest mesophyll and also significantly larger average values of all anatomical parameters of the shoots. The photosynthetic assimilation was significantly higher on treated plots at 200 and 400 ppm CO2 levels. In leaves on the treated plots, the sucrose concentration was lower while that of starch was higher than in trees on untreated soil. The differences in the maximum photosynthesis were relatively small. At unit ground, the leaf area provided for a wood ash-treated tree an efficient surface for CO2 assimilation, light interception and some starch storage during the growing period. PMID:26092243

  14. Seasonal dynamics of chemokine receptors and CD62L in subjects with asymptomatic skin sensitization to birch and grass pollen

    DEFF Research Database (Denmark)

    Assing, K; Bodtger, U; Poulsen, Lars K.

    2006-01-01

    Asymptomatic skin sensitization (AS) has been shown to be a risk factor for respiratory allergic disease. CCR4, CXCR1 and CD62L have all been assigned a role in the immunopathogenesis of allergy. Memory T-cell expression of CCR4, CXCR1 and CD62L has not hitherto been investigated in subjects with...

  15. Distribution patterns of soil entomopathogenic and birch symbiotic ectomycorrhizal fungi across native woodland and degraded habitats in Iceland

    OpenAIRE

    Edda Sigurdís Oddsdóttir 1971; Charlotte Nielsen; Robin Sen; Susanne Harding; Jørgen Eilenberg; Guðmundur Halldórsson 1952

    2010-01-01

    In Iceland, extensive afforestation programmes have been initiated, often involving the outplanting of nursery seedling stock on eroded land. In some areas high seedling mortality, to a large extent due to root damage caused by Otiorhynchus spp. larvae, has been reported. Even though recent studies have shown that inoculation with entomopathogenic and ectomycorrhizal fungi may reduce the effects of Otiorhynchus spp. on seedling mortality, information on the occurrence and distribution of thes...

  16. Responsiveness of the major birch allergen Bet v 1 scaffold to the gastric environment: Impact on structure and allergenic activity

    DEFF Research Database (Denmark)

    Sancho, Ana I; Wangorsch, Andrea; Jensen, Bettina M;

    2011-01-01

    Four Bet v 1 homologous food allergens from celeriac (rApi g 1), apple (rMal d 1), peach (rPru p 1) and hazelnut (rCor a 1), were used to probe the structural responsiveness of the Bet v 1 scaffold to gastric digestion conditions and its impact on allergenicity.......Four Bet v 1 homologous food allergens from celeriac (rApi g 1), apple (rMal d 1), peach (rPru p 1) and hazelnut (rCor a 1), were used to probe the structural responsiveness of the Bet v 1 scaffold to gastric digestion conditions and its impact on allergenicity....

  17. Structure and reaction studies of biological organic and inorganic composite materials: Abalone shells, diatoms, and a unique birch bark

    Science.gov (United States)

    Zaremba, Charlotte Marie

    Biopolymer/calcium carbonate composites grown on inorganic abiotic substrates implanted between the shell and the shell-secreting epithelium of live red abalones (Haliotis rufescens) results in an unusual highly (104)-oriented aggregate of microcrystalline calcite that precedes nacre deposition. Calcite of this orientation has never before been observed in nature. Also with this method, nacre deposition is found to correct for calcite surface roughness and chemically anomalous surfaces. Pole figure X-ray diffraction studies of these "flat pearls" provide comparisons of preferred orientation of the various mineral components of the abalone shell. Complete conversion of the aragonite in abalone nacre to hydroxyapatite in hydrothermal phosphate solution results in an oriented polycrystalline aggregate with ultrastructure preservation and an unexpected preferred orientation different from that of other biominerals and abiogenic CaCO3 samples subjected to this reaction. The new orientation, which increases with reaction time, may result from the organization of the organic matrix in the nacre, which directs the hydrothermal solution through the material. This orientation suggests strongly that the conversion proceeds via a dissolution-recrystallization mechanism, rather than by topotaxy, which was previously proposed. In addition to cellulose I, a highly oriented cellulose-II-like polymer was found in the bark of Prunus serrula, an exceptionally strong, tough, and extensible composite film. The cellulose II polymorph, which has not previously been found in nature, may be accordion-folded in the plane of the bark thickness and contribute to the strength and unusual behavior with plasticization of this natural film. The silica frustule of the diatom Skeletonema costatum has a surface area of 135 mm2/g and contains 1.5--2 wt % occluded organic. This organic includes a water-insoluble scaffolding. When treated with organic oxidizers, the chitin secreted by the diatom Thalassiosira weisflogii forms a flexible paperlike composite. A mild, rapid synthesis of hydrated sodium aluminosilicate sodalite, Na 3(AlSiO4)3·4H2O, synthesis of mesoporous silica at neutral pH, and the synthesis of gem-quality opal also are presented.

  18. Dominating IgE-binding epitope of Bet v 1, the major allergen of birch pollen, characterized by X-ray crystallography and site-directed mutagenesis

    DEFF Research Database (Denmark)

    Spangfort, Michael D; Mirza, Osman; Ipsen, Henrik;

    2003-01-01

    Specific allergy vaccination is an efficient treatment for allergic disease; however, the development of safer vaccines would enable a more general use of the treatment. Determination of molecular structures of allergens and allergen-Ab complexes facilitates epitope mapping and enables a rational...

  19. Disinfection of foot-and-mouth disease and African swine fever viruses with citric acid and sodium hypochlorite on birch wood carriers

    Science.gov (United States)

    Transboundary animal disease viruses such as foot-and-mouth disease virus (FMDV) and African swine fever virus (ASFV) are highly contagious and cause severe morbidity and mortality in livestock. Proper disinfection during an outbreak can help prevent virus spread and will shorten the time for contam...

  20. Dependence of Guaiacol Peroxidase Activity and Lipid Peroxidation Rate in Drooping Birch (Betula pendula Roth and Tillet (Tilia cordata Mill Leaf on Motor Traffic Pollution Intensity

    Directory of Open Access Journals (Sweden)

    Elena A. Erofeeva

    2015-06-01

    Full Text Available Hormesis and paradoxical effects are frequently found for different plant parameters. These phenomena were also observed for lipid peroxidation (LP rate at environmental pollution. However, the role of antioxidant enzymes, particularly guaiacol peroxidases (GPX, in a nonmonotonic variation in the LP rate remains insufficiently explored. Therefore, dependence of GPX activity and LP rate in Betula pendula and Tilia cordata leaf on motor traffic pollution intensity was studied. Regression analysis revealed dependences of LP rate and GPX activity on traffic intensity. In B pendula, GPX activity enhanced significantly (up to 2.8 times relatively control under increased traffic that induced biphasic paradoxical effect for LP rate. In the first phase, LP level increased in comparison with the control, and in the second phase, it was normalized by enhanced GPX activity. In T cordata, dependences of GPX activity and LP rate on traffic pollution were paradoxical effects. However, there was no connection between change of GPX activity and LP rate under middle- and high-level pollution: LP level reduced relatively the control or normalized even if GPX activity was lower than the control. This indicates that in T cordata, other regulatory mechanisms instead of GPX were activated which could control LP rate under middle- and high-level pollution.

  1. 助剂对桦木单板漂白与耐光性的影响%Effects of Agents on Bleached Birch Veneers and the Light Fastness

    Institute of Scientific and Technical Information of China (English)

    黄丽; 于志明

    2009-01-01

    在桦木单板漂白的基础上,考察添加助剂种类、用量以及处理方式对单板漂白效果及漂后单板耐光性的影响.结果表明:助剂的使用不影响单板漂白,单板可以获得较高白度,同时能够减缓光变色引起的白度下降的趋势;漂洗阶段添加浓度为0.4%的苯骈三唑,漂后单板的耐光性能较为理想.

  2. 波动干燥工艺对桦木干燥应力的影响%Effect of Fluctuant Drying on Drying Stresses in Birch

    Institute of Scientific and Technical Information of China (English)

    董会军; 赵寿岳; 刘文山

    2005-01-01

    进行了桦木波动干燥工艺和常规干燥工艺的对比试验.结果表明:波动干燥过程中,在降温干燥阶段,木材厚度方向上温度梯度和含水率梯度方向保持一致.与常规干燥工艺相比,含水率梯度和干燥应力小,可有效避免干燥过程中开裂现象的产生.

  3. Effect of betulin-containing extract from birch tree bark on α-amylase activity in vitro and on weight gain of broiler chickens in vivo.

    Science.gov (United States)

    Ilyina, Anna; Arredondo-Valdés, Roberto; Farkhutdinov, Salavat; Segura-Ceniceros, Elda Patricia; Martínez-Hernández, José Luis; Zaynullin, Radik; Kunakova, Rayhana

    2014-03-01

    In vitro effect of betulin-containing extract from Betula pendula Roth. bark on alpha-amylase activity was studied, the kinetic mechanism of interaction was proposed and in vivo effect of betulin-containing extract on weight gain and meat quality of broiler chickens was evaluated. The highest level of inhibitory activity (20%) was detected in extract concentration of 1,000 mg/L. Increased extract concentration did not lead to increased enzyme inhibition. Using Dixon and Cornish-Bowden coordinates, the competitive mechanism of inhibition was demonstrated. Calculated kinetic parameters were: Km equal to 0.6 mg/mL, Vmax equal to 2.6 and 2.1 mM/min from Lineweaver-Burk and Dixon coordinates, respectively and Ki equal to 3,670 ± 230 mg/mL. The partial inhibition of enzyme indicates the existence of low concentration of active inhibitory form, which reaches saturation level with increased extract concentration in applied suspension. Therefore, Ki has an apparent constant character. This partial inhibition of amylase activity observed in in vitro assay did not affect weight gain and meat quality of broiler chickens during in vivo assay. Rather, the tendency to increase the weight of edible parts and muscles compared to diet without additive suggests that the extract may be a potential food additive in poultry farming. Additionally, it could be a source for further pharmaceutical and pharmacological research.

  4. Influence of Cutting on Hydrological Effect of Oak and Birch Forest%采伐对柞桦林水文效应的影响

    Institute of Scientific and Technical Information of China (English)

    王亚利; 苑国建

    2013-01-01

    通过对柞桦林与其采伐迹地小区径流对比试验表明:柞桦林采伐后,林冠层截留功能丧失,灌草层、枯枝落叶层截留有所增大,地表径流系数增大73.3%,说明采伐对林地的产流有一定的影响;观测结果表明,柞桦林比采伐迹地产生的地表径流、壤中流少;在降水量少于50 mm的情况下,柞桦林地一般不出现壤中流.

  5. 大通白桦林改造措施及成效分析%Reconstruction Measure and Effect of Birch Forest in Datong

    Institute of Scientific and Technical Information of China (English)

    赵竹梅

    2010-01-01

    大通县白桦低效林在白桦林分中占29%,在乔木林中占10.6%,且有逐年增加的趋势.通过对大通县老爷山公园后山白桦更新造林措施、成效分析,提出白桦林改造的较好途径.

  6. On Natsume Soseki's Literary Influence On the White Birch School%论夏目漱石对白桦派作家的文学影响

    Institute of Scientific and Technical Information of China (English)

    西垣勤; 刘立善

    2006-01-01

    具有强烈社会意识的夏目漱石,在其创作中重点关注阶级社会中的上流阶级和中流阶级的青年知识分子.这一阶级的代表是白桦派的青年作家.白桦派作家尊敬漱石的人格与文格,并受其影响,但白桦派作家对漱石流露作品中严肃批判现实的主体意识,并未充分理解与认可,从而凸显了白桦派理想主义的天真性.

  7. Luria's Model of the Verbal Control of Behavior. Study F: Motivational and Control in the Development of Language Functions, D. Birch.

    Science.gov (United States)

    Beiswenger, Hugo

    A. R. Luria, in his conception of the verbal control of behavior, regards four fundamental and distinctive functional attributes of the human speech system as making up a signaling system that humans alone possess: (1) the nominative role of language, (2) the generalizing or semantic role, (3) the communicative role, and (4) the role of…

  8. Recycling of wood- and peat-ash – a successful way to establish full plant cover and dense birch stand on a cut-away peatland

    OpenAIRE

    Huotari, N. (Noora)

    2011-01-01

    Abstract Mechanical harvesting of peat changes the original mire ecosystem completely, and without active measures these areas may remain non-vegetated even for decades. Afforestation is one of the most popular after-use options for cut-away peatlands in Finland since it has both economic and aesthetic values. Recycling of wood-ash as a fertilizer has been studied extensively in peatlands drained for forestry. Wood-ash is reported to promote tree growth in these areas without any signific...

  9. A case of birch pollen-related food allergy syndrome%桦树花粉相关的食物过敏综合征一例

    Institute of Scientific and Technical Information of China (English)

    邵洁; 罗海燕; A Purohit; G Pauli

    2005-01-01

    70%以上桦树花粉过敏患者同时存在对某些植物源性食物过敏,即所谓的花粉相关的食物过敏(pollen related food allergy)。我们报道1例典型的桦树花粉过敏,随后发展成为对一些植物性食物过敏,并产生显著的临床症状,籍此阐明桦树花粉相关的食物过敏的临床和免疫学特征。

  10. Birches against mineral oils. Lignin - a renewable resource for the alternative production of phenols; Birke contra Erdoel. Lignin - ein nachwachsender Rohstoff zur alternativen Gewinnung von Phenolen

    Energy Technology Data Exchange (ETDEWEB)

    Zehnpfund, C.; Bormann, J.; Wehrkamp zu Hoene, F. [Gymnasium Bersenbrueck (Germany)

    1998-02-01

    We wanted to offer an alternative for the `After-mineral oil time` with our work when we attempted to isolate phenols, which are won up to now from mineral oil, of a growing raw material. Phenols are economic important substances for production of epoxies, herbicides, artificial resins, dyes and drugs (e.g. aspirin or Paracetamol). We managed to isolate phenols with normal conditions of lignin, a component of wood. (orig.) [Deutsch] Wir wollten mit unserer Arbeit eine Alternative fuer die `Nach-Erdoel-Zeit` bieten, indem wir versuchten, Phenole, die bisher aus Erdoel gewonnen werden, aus einem nachwachsenden Rohstoff zu isolieren. Phenole sind volkswirtschaftlich bedeutsame Substanzen zur Herstellung von Kunststoffen, Herbiziden, Kunstharzen, Farbstoffen und Arzneimitteln (z.B. Aspirin oder Paracetamol). Es gelang uns, Phenole unter Normalbedingungen aus Lignin, einem Bestandteil des Holzes, zu isolieren. (orig.)

  11. Crystallization and preliminary X-ray analysis of birch-pollen allergen Bet v 1 in complex with a murine monoclonal IgG Fab' fragment

    DEFF Research Database (Denmark)

    Spangfort, M D; Mirza, Osman Asghar; Gajhede, M

    1999-01-01

    The human type I allergic response is characterized by the presence of allergen-specific serum immunoglobulin E (IgE). Allergen-mediated cross-linking of receptor-bound IgE on the surface of mast cells and circulating basophils triggers the release of mediators, resulting in the development of th......, with unit-cell parameters a = 91.65, b = 99.14, c = 108.90 A, alpha = 105.7, beta = 98.32, gamma = 97.62 degrees, and diffract to 2.9 A resolution when analyzed at 100 K using synchrotron-generated X--rays....

  12. Root system traits of Norway spruce, Scots pine, and silver birch in mixed boreal forests: an analysis of root architecture, morphology, and anatomy

    OpenAIRE

    Kalliokoski, Tuomo

    2011-01-01

    The aim of this thesis was to unravel the functional-structural characteristics of root systems of Betula pendula Roth., Picea abies (L.) Karst., and Pinus sylvestris L. in mixed boreal forest stands differing in their developmental stage and site fertility. The root systems of these species had similar structural regularities: horizontally-oriented shallow roots defined the horizontal area of influence, and within this area, each species placed fine roots in the uppermost soil layers, w...

  13. Environ: E00796 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00796 Birch Medicinal herb Quercetin [CPD:C00389], Kaempferol [CPD:C05903], Salicy...late, Tannin, Ascorbate [CPD:C00072] Betula pendula [TAX:3505] Betulaceae Birch leaves Medicinal herbs [BR:br08322] Dicot plants: rosids Betulaceae (birch famly) E00796 Birch ...

  14. Effects of Water Extracts of from Different Parts of Birch and Larch on Biomass Accumulation of One-Year-Old Birch and LarchSeedlings%白桦、落叶松器官浸提液对1年生白桦、落叶松苗木生物量的影响

    Institute of Scientific and Technical Information of China (English)

    孙欣欣; 刘忠玲; 王庆成; 赵羿鸾; 刘超群; 孙忻; 袁野

    2011-01-01

    采用盆栽方法,研究了白桦、落叶松根、枝、叶浸提液对1年生白桦(Betula platyphylla)和落叶松(Larixgmelini)苗木生物量及其分配的影响.结果表明:质量浓度为0.05g/mL的落叶松枝浸提液处理,使白桦苗木总生物量提高24.0% (p<0.05),同时显著提高了白桦苗木根、叶的生物量积累、根质量比和根冠比(p<0.05).白桦枝、叶浸提液、落叶松枝浸提液使落叶松苗木总生物量分别提高17.4%、16.8%和23.9%(p<0.05);白桦叶浸提液显著提高了落叶松根生物量、根质量比和根冠比(p<0.05).白桦、落叶松根、枝、叶部分浸提液对2树种苗木的生物量及生物量分配产生了显著影响,初步确定二树种间存在一定的化感作用.

  15. Effect of Environment Humidity on the Dimension Stability of White Birch Lumber%环境湿度对白桦木材尺寸稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    苗平; 王松林; 周方赟

    2015-01-01

    对白桦木材在不同环境湿度下的尺寸稳定性进行了试验研究,试验表明:白桦小试件的含水率随环境湿度变化的时间较短,在正常的湿环境中1~2d内就与周围的环境达到平衡;较大尺寸的家具拼板材在干燥的环境中解吸速度较慢,需要较长的时间,同样在潮湿的环境中吸湿较慢,要达到与周围的环境相平衡同样需要比小试件更长的吸湿时间.

  16. 人工模拟降水条件下旱作农田土壤“Birch效应”及其响应机制%Response of soil "Birch Effect" to simulated rainfalls in dry croplands

    Institute of Scientific and Technical Information of China (English)

    陈荣荣; 刘全全; 王俊; 刘文兆; Upendra M.Sainju

    2016-01-01

    降水事件引起干土复湿刺激土壤CO2脉冲释放的现象被称为“Birch效应”,其作用机制可能是降水刺激土壤“底物供给”增加或引起土壤“微生物胁迫”所致.为深入了解土壤“Birch效应”对降水格局改变的响应过程及内在机制,在冬小麦拔节期和夏闲期分别进行了不同降水量(1-32 mm)人工模拟降水实验,系统观测了降水后0-72 h土壤呼吸及土壤碳组分变化特征,结果表明:土壤呼吸随降水量的增大而增强,1-16 mm降水土壤呼吸峰值出现在降水后4h,而32 mm降水土壤呼吸峰值出现时间滞后了4h.与较小降水量相比,较大的降水量能增加土壤呼吸但会推迟土壤呼吸峰值出现时间.土壤呼吸速率峰值(SR-P)与降水量(P)呈幂相关(拔节期:SR-P=0.97P0.09,R2 =0.5,P<0.05;夏闲期:SR-P=1.07P0.09,R2=0.98,P<0.01).降水后72 h累积CO2释放量(CO2-P)与降水量呈线性相关(拔节期:CO2-P=0.03P+5.99,R2=0.58,P<0.05;夏闲期:CO2-P=0.11P+6.04,R2=0.86,P<0.01).土壤呼吸温度敏感性系数和降水量之间存在二次曲线关系(拔节期:Q10=-0.007P2 +0.2P+0.7,R2=0.32 P<0.05;夏闲期:Q10 =-0.01P2 +0.3P+0.2,R2=0.86,P<0.01).逐步回归分析表明,冬小麦拔节期所有降水量处理土壤呼吸与土壤微生物量碳相关性均达到显著水平(P<0.05),指示土壤“Birch效应”是由“微生物胁迫”所致.而在夏闲期,当降水量小于8 mm时土壤呼吸与微生物量碳相关性显著,即以微生物胁迫机制占主导;8 mm降水处理下土壤呼吸与氯仿熏蒸-K2SO4提取态有机碳相关性达到极显著水平,指示则为两种机制共同起作用,而当降水量大于16 mm时,土壤呼吸主要与可提取态有机碳显著相关,“Birch”效应转为以底物供给机制占主导.与夏闲期相比,冬小麦拔节期作物生长会削弱“Birch效应”,并改变其响应机制.

  17. 表面处理对淀粉基API桦木接头耐老化性能的影响%Effects of Surface Treatment on the Aging Resistance Properties of Starch Based API Birch Joint

    Institute of Scientific and Technical Information of China (English)

    时君友; 柴瑜; 徐文彪; 王淑敏; 麻馨月

    2014-01-01

    以淀粉基API胶合桦木胶接结构为研究对象,以胶接接头的压缩剪切强度为评估指标,对桦木表面不同处理后的表面形态、化学变化与剪切强度等方面进行了研究.结果表明:不同处理方法,均能提高胶接接头的耐久性,不同表面处理方法对粘接接头剪切强度下降趋势为:砂纸打磨处理>化学氧化处理>偶联剂处理.

  18. 穆棱地区典型杨桦天然次生中幼林经营效果调查分析%Analysis of the Effect of the Application on Typical Poplar-birch Forest

    Institute of Scientific and Technical Information of China (English)

    崔玉柱; 何晓红; 魏彪; 周冬跃

    2013-01-01

    通过标准地调查,对比研究林冠下引进红松的经营措施对天然杨桦中幼次生林的影响效果.调查发现,对林冠下引进红松的经营不但可以得到间伐材,还可以提高林分的树种丰富度、改善林分结构、提高林分质量、增加公顷株树和平均胸径,进而显著提高林分公顷蓄积.

  19. Application of the MASSAHAKE-method for birch whole tree chips and for the production of raw material for mechanical pulp production; MASSAHAKE-menetelmaen soveltaminen koivulle sekae mekaanisen massan raaka-ainetuotantoon

    Energy Technology Data Exchange (ETDEWEB)

    Ahonen, M.; Seppaenen, V.; Nikala, L.

    1996-12-31

    The objectives of this project for the year 1995 were: (1) To develop the grinding process in order to decrease the wood losses in grinder, (2) To find the connection between the initial values in the process and the quality of the pulp chips, (3) To find out the behaviour of chips from mixed tree species in the MASSAHAKE process, (4) To find out the amount of knots in the pulp chips from the MASSAHAKE-process and (5) To find out the critical factors in big fuel stock made of the fuel fraction from the MASSAHAKE-process. The research with grinder was made with five different types of grinder plates. One of the blade sets was used as a reference where all the other sets were compared. In the second task a relationship between three most important initial values and the quality of pulp chips was determined. These values were: the feeding capacity of the whole tree chips to the process, the sensitivity of the optical sorter and the pixel size of bark to be removed in optical sorter. Based on the research and analysis results a linear model describing the process was made. In the third task the behaviour of mixed tree chips in the process was examined and also some full scale pulping experiments were done. Comparing the knot content of the pulp chips both from MASSAHAKE-process and normal pulp chip process a significant difference was noticed. The pulp chips from MASSAHAKE-system contained only 1/3 of the knots in normal de-barking+chipping pulp chip line. With decreased knot content a 1-3 % increase in digester capacity could be reached. Finally in fuel fraction storing research a significant dry material loss was determined

  20. Living at the margin of the retreating Fennoscandian Ice Sheet

    DEFF Research Database (Denmark)

    Möller, P.; Östlund, O.; Barnekow, L.;

    2013-01-01

    During an archaeological survey in Pajala parish, northernmost Sweden, clusters of quartz waste from knapping and burnt bone were discovered on a glaciofluvial gravel plateau close to Aareavaara village in the Muonio River valley. Sampled materials from a larger area and small-scale excavations (in...... a subarctic birch woodland tundra landscape characterized by open vegetation, including occasional birch trees and an abundance of willow and dwarf birch. © The Author(s) 2012....

  1. Selective Solvents for Extraction of Triterpenes from Betula Pendula Outer Bark

    OpenAIRE

    Pāže, A; Zandersons, J; Rižikovs, J; Dobele, G.; Jurkjāne, V; Spince, B

    2013-01-01

    The volume of birch plywood production in Latvia is illustrated by the 208 000 m3 of plywood sold in 2011 and about 562 000 m3 of processed birch veneer blocks. Wood residues such as bark, veneer shorts, cut off ends and others are used as a fuel. It would be more expedient to increase the birch wood utilisation degree by involving also birch outer bark in the processing cycle. It makes up 2% of the veneer blocks’ mass. At the J.S.C. “Latvijas Finieris”, about 6000 t per year of graded and mi...

  2. Can antibrowsing defense regulate the spread of woody vegetation in arctic tundra?

    Science.gov (United States)

    Bryant, John P.; Joly, Kyle; Chapin, F. Stuart; DeAngelis, Donald L.; Kielland, Knut

    2014-01-01

    Global climate warming is projected to promote the increase of woody plants, especially shrubs, in arctic tundra. Many factors may affect the extent of this increase, including browsing by mammals. We hypothesize that across the Arctic the effect of browsing will vary because of regional variation in antibrowsing chemical defense. Using birch (Betula) as a case study, we propose that browsing is unlikely to retard birch expansion in the region extending eastward from the Lena River in central Siberia across Beringia and the continental tundra of central and eastern Canada where the more effectively defended resin birches predominate. Browsing is more likely to retard birch expansion in tundra west of the Lena to Fennoscandia, Iceland, Greenland and South Baffin Island where the less effectively defended non-resin birches predominate. Evidence from the literature supports this hypothesis. We further suggest that the effect of warming on the supply of plant-available nitrogen will not significantly change either this pan-Arctic pattern of variation in antibrowsing defense or the resultant effect that browsing has on birch expansion in tundra. However, within central and east Beringia warming-caused increases in plant-available nitrogen combined with wildfire could initiate amplifying feedback loops that could accelerate shrubification of tundra by the more effectively defended resin birches. This accelerated shrubification of tundra by resin birch, if extensive, could reduce the food supply of caribou causing population declines. We conclude with a brief discussion of modeling methods that show promise in projecting invasion of tundra by woody plants.

  3. Comparisons of measured and modelled ozone deposition to forests in northern Europe

    DEFF Research Database (Denmark)

    Touvinen, J.P.; Simpson, D.; Mikkelsen, Teis Nørgaard;

    2001-01-01

    in Denmark) and one deciduous forest (mountain birch in Finland). On average, themodel performs well for the Scots pine forest, if local inputdata are used. The daytime deposition rates are somewhat over-predicted at the Danish site, especially in the afternoon. The mountain birch data indicate...

  4. 培养基及6BA与蔗糖浓度对白桦茎叶去分化率的影响%An effect of culture medium,6BA and soucrose density on dedifferentiational rate of birch leaf and stem

    Institute of Scientific and Technical Information of China (English)

    丁云峰; 马艳丽

    2005-01-01

    在培养白桦试管苗的去分化阶段进行不同培养基、6BA浓度、蔗糖浓度对茎、叶去分化率影响的比较试验,结果表明:以MS+NAA0.1mg/L+IBA0.5mg/L为基本培养基时,茎、叶的去分化效果较好,并且添加的蔗糖浓度越低,越适于茎的分化,浓度较高,越适于叶的分化.

  5. Frequent occurrence of T cell–mediated late reactions revealed by atopy patch testing with hypoallergenic rBet v 1 fragments

    Science.gov (United States)

    Campana, Raffaela; Moritz, Katharina; Marth, Katharina; Neubauer, Angela; Huber, Hans; Henning, Rainer; Blatt, Katharina; Hoermann, Gregor; Brodie, Tess M.; Kaider, Alexandra; Valent, Peter; Sallusto, Federica; Wöhrl, Stefan; Valenta, Rudolf

    2015-01-01

    Background Late allergic reactions are common in the course of allergen-specific immunotherapy and even occur with allergy vaccines with reduced IgE reactivity. Objective We sought to study atopy patch test (APT) reactions and T-cell responses to the recombinant birch pollen allergen Bet v 1 and recombinant hypoallergenic T-cell epitope–containing Bet v 1 fragments in patients with birch pollen allergy with and without atopic dermatitis (AD). Methods A clinical study was conducted in 15 patients with birch pollen allergy with AD (group 1), 5 patients with birch pollen allergy without AD (group 2), 5 allergic patients without birch pollen allergy (group 3), and 5 nonallergic subjects (group 4) by performing skin prick tests and APTs with rBet v 1 and hypoallergenic rBet v 1 fragments. T-cell, cutaneous lymphocyte antigen (CLA)+ and CCR4+ T-cell and cytokine responses were studied by thymidine uptake, carboxyfluorescein diacetate succinimidyl ester staining, and Luminex technology, respectively. Results rBet v 1 and hypoallergenic rBet v 1 fragments induced APT reactions in not only most of the patients with birch pollen allergy with AD (11/15) but also in most of those without AD (4/5). Patients with birch pollen allergy with AD had higher Bet v 1–specific proliferation of CLA+ and CCR4+ T cells compared with patients with birch pollen allergy without AD. There were no differences in Bet v 1–specific CLA+ and CCR4+ proliferation and cytokine secretion in patients with and without APT reactions. Conclusion Hypoallergenic rBet v 1 fragments induce T cell–dependent late reactions not only in patients with birch pollen allergy with AD but also in those without AD, which can be determined based on APT results but not based on in vitro parameters. PMID:26518092

  6. Foliar responses of understorey Abies lasiocarpa to different degrees of release cutting of Betula papyrifera and conifer mixed species stand

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.R.; Letchford, T. [Ministry of Forests, Prince George, BC (Canada). Red Rock Research Station; Comeau, P.G. [BC Ministry of Forests, Victoria, BC (Canada); Coopersmith, D. [BC Ministry of Forests, Prince George, BC (Canada)

    2000-07-01

    Foliar responses of subalpine fir (Abies lasiocarpa (Hook.) Nutt.) to thinning were studied in a 35-yr-old mixed stand of paper birch (Betula papyrifera Marsh.) and conifers. The stand regenerated naturally after a wildfire with a canopy dominated by paper birch (average height 9.8 m) and an understorey dominated by subalpine fir (average height 1.6 m). The stand was thinned to four densities of birch: 0, 600 and 1200 stems ha{sup -1} and control (Unthinned at 2300-6400 stems ha{sup -1}) in the autumn of 1995. The understorey conifers, mainly subalpine fir, were thinned to 1200 stems ha{sup -1}. The study used a completely randomized split-plot design. Three sample trees were systematically selected from each treatment replicate and each tree stratum (upper, intermediate and lower understorey). One-year-old and older age class needles were collected from one south-facing branch within the fifth whorl from the tree top. Thinning of paper birch significantly (p<0.001) increased leaf area and dry weight per 100 needles for intermediate and short trees except in the 0 birch treatment. Understorey subalpine fir trees in 600 stems ha{sup -1} birch (T3) had the largest leaf area and leaf dry weight per 100 1-yr-old needles. Specific leaf area (SLA) decreased from unthinned (T1) to 0 birch (T4). Lower understorey trees had the largest SLA. One-year-old needles had significantly higher N, P and K concentrations in all the thinning treatments. These responses are consistent with the shade tolerance of subalpine fir. The results suggest that when managing a paper birch-conifers mixed wood forest it may be of benefit to understorey conifers to leave a birch canopy as a nursing crop.

  7. Air pollution and the respiration of certain tree species

    Energy Technology Data Exchange (ETDEWEB)

    Makedonska, T.; Slavova, V.

    1973-01-01

    These studies are conducted to compare the effects of air pollution on horse chestnut (Aesculus hippocastanum L.), London plane (Platanus acerifolia Milld.) ash-leaved maple (Acer negundo L.) and European birch (Betula alba L.). With increasing concentrations of air pollution these species react by increasing the intensity of respiration, as in separate cases the increase reaches up to 40%. Most sensitive to air pollution is the horse chestnut, followed by birch and ash-leaved maple; least sensitive is London plane. With respect to gas resistance birch and ash-leaved maple rank close to the horse chestnut but are more resistant than the horse chestnut and less sensitive than London plane.

  8. Morphology of Betula pendula var. carelica bark at the pre-reproductive stage

    Directory of Open Access Journals (Sweden)

    Nadezhda N. Nikolaeva

    2014-04-01

    Full Text Available Changes in bark morphology at the pre-reproductive stage of Karelian birch are for the first time considered in connection with the type of trunk surface. The bark surface in Karelian birch changes with age from smooth to fissured. At the pre-reproductive stage Karelian birch has smooth bark with different types of exfoliation of the phellem surface layers, and tubercular specimens feature locally fissured bark on muffs at the very onset of their formation, as well as early rhytidome formation. Morphology of the bark tissues complex is a reflection of direction and intensity of the internal processes of the plant.

  9. 78 FR 32270 - Kenai National Wildlife Refuge, Soldotna, AK; Environmental Impact Statement for the Shadura...

    Science.gov (United States)

    2013-05-29

    ... of the effects of those alternatives. The Service does not have a preferred alternative. DATES... extend from sea level to 1,800 feet and are composed of spruce and birch forests, which on the Refuge...

  10. Double-blind, placebo-controlled food challenge with apple

    DEFF Research Database (Denmark)

    Skamstrup Hansen, K; Vestergaard, H; Stahl Skov, P;

    2001-01-01

    The aim of the study was to develop and evaluate different methods of double-blind, placebo-controlled food challenge (DBPCFC) with apple. Three different DBPCFC models were evaluated: fresh apple juice, freshly grated apple, and freeze-dried apple powder. All challenges were performed outside...... the pollen season and took place from 1997 to 1999. The freeze-dried apple material was characterized by means of leukocyte histamine release (HR), skin prick test (SPT), and immunoblotting experiments. The study population consisted of birch pollen-allergic patients with a history of rhinitis in the birch......-pollen season and positive specific IgE to birch. For comparison of the DBPCFC models, 65 patients with a positive open oral challenge with apple were selected. In the characterization of the freeze-dried apple material, 46 birch pollen-allergic patients were included. The IgE reactivity to apple was evaluated...

  11. ACCUMULATION OF HEAVY METALS IN LEAF LITTER OF DIFFERENT TREE SPECIES IN URBAN AREAS

    OpenAIRE

    Konoshina, S.; Khilkova, N.

    2015-01-01

    Analysis of heavy metal accumulation of leaf litter of woody plants: Aesculus hippocastanum Aesculus hippocastanum, heart-shaped linden Tilia cordata, Siberian larch Larix sibirica, mountain ash Sorbus aucuparia, warty birch Betula verrucosa, growing within Orel City is given. The kinds of woody plants, which leaf litter has the largest accumulation of heavy metals are determined. The maximum total content of heavy metals in leaf litter was observed in mountain ash and birch.

  12. A Note on the Completeness of an Exponential Type Sequence

    Institute of Scientific and Technical Information of China (English)

    Jinhui FANG

    2011-01-01

    For any given coprime integers p and q greater than 1, in 1959, B. J. Birch proved that all sufficiently large integers can be expressed as a sum of pairwise distinct terms of the form paqb. As Davenport observed, Birch's proof can be modified to show that the exponent b can be bounded in terms of p and q. In 2000, N. Hegyvari gave an effective version of this bound. The author improves this bound.

  13. An Approach of Traffic Clustering for Reconfigurable Network%一种面向可重构网络的业务聚类方法

    Institute of Scientific and Technical Information of China (English)

    江逸茗; 兰巨龙; 郭通; 田铭

    2013-01-01

    Since the traditional network architectures faced the problems of structural rigidity, functional simplification and poor controllability, the reconfigurable network is designed as a new kind of network architecture. In the reconfigurable network, traffic clustering is the key mechanism. By detailed analysis of the requirement of traffic clustering and the characteristics of clustering algorithms, Balanced Iterative Reducing and Clustering using Hierarchies (BIRCH) algorithm is chosen for traffic clustering. However, this algorithm has a poor performance in identifying clusters of arbitrary shapes. In order to solve this issue, an advanced algorithm named Advanced Split BIRCH (AS-BIRCH) is designed. Experimental results demonstrate the effectiveness of AS-BIRCH in traffic clustering.%  可重构网络是在传统网络体系结构僵化、功能单一、可控性差的背景下提出的一种新型网络体系架构,业务聚类是可重构网络的关键机制之一。该文通过对业务聚类需求和聚类算法特性的详细分析,选择了基于平衡迭代规约的层次聚类(Balanced Iterative Reducing and Clustering using Hierarchies, BIRCH)算法来实现业务的聚类;并针对BIRCH对任意形状的簇识别能力差的缺点,设计了一种分裂改进型BIRCH(Advanced Split BIRCH, AS-BIRCH)算法;实验证明该算法在业务聚类方面取得了较好的效果。

  14. Tree recruitment in the Forest-tundra Ecotone : Limitation and facilitation processes in contrasting climatic Regions

    OpenAIRE

    Albertsen, Elena

    2012-01-01

    Aim: The aim of this study was to analyse how abiotic and biotic constraint and facilitation agents determine tree recruitment in the alpine zone in climatically different regions as well as across species; Birch, pine and spruce. Location: The study was located to Grødalen, Haltdalen and Røros representing a coastal-inland gradient, where birch was included along the entire climatic gradient and all three species in one region (Haltdalen). Methods: Variables collected for seedling/...

  15. Polyurethane Foam from Industrial Waste of Plywood Production

    OpenAIRE

    Pāže, A; Zandersons, J; Stirna, U; Rižikovs, J; Tardenaka, A; Spince, B

    2013-01-01

    This study shows the possibility of using birch bark, a by-product of plywood production, for preparing polyurethane foam. A birch bark lignocellulose component – inner bark – was liquefied to obtain a polyurethane raw material – polyol mixture. Outer bark, containing valuable biologically active pentacyclic triterpenes (betulin, lupeol, betulinic acid, etc.), after extracting those compounds, was subjected to hydrothermal treatment in alkaline medium, and the other main inner bark component ...

  16. A randomized, double-blind, placebo-controlled exploratory study to evaluate the potential of Pycnogenol(R) for improving allergic rhinitis symptoms

    OpenAIRE

    Schonlau, Frank

    2010-01-01

    Abstract We explored the potential of Pycnogenol? for relieving allergic rhinitis (birch pollen) symptoms in a double-blind, placebo-controlled trial. In 2008 19 subjects started treatment three weeks prior to the onset of birch pollen season in Ontario Canada. While there was an improvement of eye and nasal symptoms with Pycnogenol, there was no significance versus placebo. It was postulated that Pycnogenol may require a lag-time between start of therapy and the onset of action. T...

  17. Indoleamine 2,3-dioxygenase expression in patients with allergic rhinitis: a case-control study

    OpenAIRE

    Luukkainen Annika; Karjalainen Jussi; Honkanen Teemu; Lehtonen Mikko; Paavonen Timo; Toppila-Salmi Sanna

    2011-01-01

    Abstract Background Indoleamine 2,3-dioxygenase (IDO) is a tryptophan catalyzing enzyme. It has been suggested that it has a role in lower airway allergic inflammations, but its role in allergic rhinitis has not been investigated. Objective Our aim was to evaluate the expression of IDO in the nasal mucosa of allergic rhinitis patients allergic to birch pollen during peak exposure to birch pollen allergen and compare it to non-atopic patients. Methods IDO expression was immunohistochemically e...

  18. Spatial distribution of forests and woodlands in Iceland in accordance with the CORINE land cover classification

    OpenAIRE

    Björn Traustason 1971; Arnór Snorrason 1960

    2014-01-01

    This paper presents a united geographical database for all known forest and woodland areas in Iceland, both natural and planted. This first edition of the database follows forest and woodland classifications used in the European CORINE land cover program. According to the database, the total area of forests and woodlands in Iceland was estimated as being 156,800 ha, divided into natural downy birch (Betula pubescens) woodland (115,400 ha) and forest plantations (41,400 ha). The natural birch ...

  19. Leaf and twig litter decomposition of main species in different forests along the north slope of Changbai Mountain,northeast China

    Institute of Scientific and Technical Information of China (English)

    GUO Zhongling; LI Qingkang; ZHENG Jinping; LIU Wande; FAN Chunnan; MA Yuandan; YU Guirui; HAN Shijie

    2007-01-01

    From 2001 to 2003,the litter decomposition dynamics of dominant tree species were conducted using a litterbag burying method in the broadleaf-Korean pine forest,spruce-fir forest and Ermans birch forest,which represents three altitudinal belts in Changbai Mountain,northeast China.The spatial and temporal dynamics of litter decomposition and the effects of litter properties were examined.Furthermore,the decomposition trend of different species was simulated by the Olson model,and results showed that annual mass loss rates increased over time,but was not significantly correlated.Leaf decomposition rates increased after decomposing for 638 days (1.75 years),and the order of dry weight remaining rates of leaf litter for different species is:Asian white birch (Betula platyphylla) (24.56%)<Amur linden (Tilia amurensis) (24.81%) < Korean pine (Pinus koraiensis)(38.48%)<spruce (Picea jezoensis var. microsperma)(41.15%)< Ermans birch (Betula ermanii) (41.53%)<fir (Abies nephrolepis) (42.62%).The dry weight remaining rates of twig litter was smaller than that of leaf litter,and followed the order of Amur linden (44.98%)<fir (64.62%)<Korean pine (72.07%)<spruce (73.51%)<Asian white birch (77.37%)<Ermans birch (80.35%).The simulation results by the Olson model showed that,in leaf,the 95%-decomposition rates ranged from 4.5 to 8.0 years,and annual decomposition rate (k) followed the order of Amur linden (0.686)>Asian white birch (0.624)>Korean pine (0.441)>spruce (0.406)>fir (0.397)>Ermans birch (0.385);in twig,it ranged from 7.8 to 29.3 years,and k follows the order:Amur linden (0.391)>fir (0.204)>Korean pine (0.176)>spruce (0.157)>Asian white birch (0.148)>Ermans birch (0.102).In general,the differences of decomposition rate are evident between leaf and twig litter and among species,and were higher in broad-leaved species compared with coniferous species at the same elevation,and decreased with the ascending of elevation.

  20. Phenolic compounds of the inner bark of Betula pendula: seasonal and genetic variation and induction by wounding.

    Science.gov (United States)

    Liimatainen, Jaana; Karonen, Maarit; Sinkkonen, Jari; Helander, Marjo; Salminen, Juha-Pekka

    2012-11-01

    The contents of individual phenolic compounds in the inner bark of silver birch (Betula pendula Roth) were analyzed by HPLC-DAD. Samples from 21 mature trees originating from three micropropagated parent trees were collected six times over a 1-year period. Significant seasonal variation in the quantities of ten compounds and four chromatographically unresolved compound pairs was found. A majority of the compounds also exhibited significant quantitative variation among birch clones. There were no qualitative differences associated with the season or among the clones. However, wounding of the bark induced the production of new types of bark phenolics: several ellagitannins were detected in the callus tissues of birch for the first time. PMID:23065107

  1. Biocomposite cellulose-alginate films: promising packaging materials.

    Science.gov (United States)

    Sirviö, Juho Antti; Kolehmainen, Aleksi; Liimatainen, Henrikki; Niinimäki, Jouko; Hormi, Osmo E O

    2014-05-15

    Biocomposite films based on cellulose and alginate were produced using unmodified birch pulp, microfibrillated cellulose (MFC), nanofibrillated cellulose (NFC) and birch pulp derivate, nanofibrillated anionic dicarboxylic acid cellulose (DCC), having widths of fibres ranging from 19.0 μm to 25 nm as cellulose fibre materials. Ionically cross-linked biocomposites were produced using Ca(2+) cross-linking. Addition of micro- and nanocelluloses as a reinforcement increased the mechanical properties of the alginate films remarkably, e.g. addition of 15% of NFC increased a tensile strength of the film from 70.02 to 97.97 MPa. After ionic cross-linking, the tensile strength of the film containing 10% of DCC was increased from 69.63 to 125.31 MPa. The biocomposite films showed excellent grease barrier properties and reduced water vapour permeability (WVP) after the addition of cellulose fibres, except when unmodified birch pulp was used. PMID:24423542

  2. Extraction of betulin from bark of Betula platyphylla by supercritical carbon dioxide extraction

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu-hong; YU Tao; WANG Yang

    2003-01-01

    Betulin, which is a medicinal pentacyclic triterpene, is abundant in the bark of white birch (Betula platyphlly). The bark of birch was collected at Tayuan Forest Farm of Jiagedaqi, Heilongjiang Province in September 2000. Supercritical fluid extraction (SFE) that is a new separation technology has been used for the processing pharmaceutical and natural products. In this paper, the extraction of betulin from the bark of birch by supercritical CO2 extraction was studied. The authors investigated and analyzed a few parameters such as modifier dosage, extraction pressure and extraction temperature. The optimal extraction conditions showed that the modifier dosage used for per gram bark powder was 1.5 mL, the extraction pressure was at 20 Mpa, and the extraction temperature was at 55 ℃. The velocity of flow of liquid CO2 was at 10 kg/h. The pressure and temperature in separation vessel were at 5.5 Mpa and 50 ℃, respectively.

  3. Design of plywood and paper flywheel rotors

    Science.gov (United States)

    Hagen, D. L.

    Technical and economic design factors of cellulosic rotors are compared with conventional materials for stationary flywheel energy storage systems. Wood species, operation in a vacuum, assembly and costs of plywood rotors are evaluated. Wound kraft paper, twine and veneer rotors are examined. Two bulb attachments are designed. Support stiffness is shown to be constrained by the material strength, rotor configuration and speed ratio. Plywood moisture equilibrium during manufacture and assembly is critical. Disk shaping and rotor assembly are described. Potential self-centering dynamic balancing methods and equipment are described. Detailed measurements of the distribution of strengths, densities and specific energy of conventional Finnish Birch plywood and of custom made hexagonal Birch plywood are detailed. High resolution tensile tests were performed while monitoring the acoustic emissions with micoprocessor controlled data acquisition. Preliminary duration of load tests were performed on vacuum dried hexagonal birch plywood. Economics of cellulosic and conventional rotors were examined.

  4. Effects of atmospheric CO{sub 2}, light availability and tree species on the quality of leaf detritus as a resource for treehole mosquitoes

    Energy Technology Data Exchange (ETDEWEB)

    Strand, M.; Herms, D.A.; Walker, E.D.; Merritt, R.W. [Michigan State Univ., Dept. of Entomology, East Lansing, MI (United States); Ayres, M.P. [Dartmouth College, Dept. of Biological Sciences, Hanover, NH (United States); Kubiske, M.E.; Pregitzer, K.S. [Michigan Technological Univ., School of Forestry and Lake Superior Ecosystems Research Center, Houghton, MI (United States); Kaufman, M.G. [Michigan State Univ., W.K. Kellogg Biological Station, Hickory Corners, MI (United States)

    1999-07-01

    Elevated CO{sub 2} could alter the productivity of heterotrophic aquatic ecosystems through effects on allochthonous litter inputs. The effects of atmospheric CO{sub 2} concentration, light availability to trees and tree species, on leaf detritus quality as a food resource for eastern treehole mosquitoes (Aedes triseriatus) were examined. Larvae were reared in laboratory microcosms (simulated treeholes) with naturally-senesced, abscised foliage from seedlings of red oak (Quercus rubra) and paper birch (Betula papyrifera) grown in ambient and elevated atmospheric CO{sub 2} environments. Elevated CO{sub 2} did not have significant effects on any measure of mosquito performance. In contrast, host species and light availability had dramatic effects on mosquito development time and survival; light availability had additional effects on adult size. Mosquito reproductive potential ({+-} SE) averaged 8.4 {+-} 1.5 females female{sup -1}) generation{sup -1} when litter input was from birch-sun leaves, but was 19.6 {+-} 1.8 when the litter was from birch-shade leaves and 13.0 {+-} 1.8 when from oak-sun leaves. Mosquito development time was nearly halved when the litter input was from oak-sun leaves versus birch-sun leaves, suggesting a potential for even greater demographic effects (e.g. two generations per year instead of one could yield a 20-fold increase in annual growth rate). Trophic transfer rates (mg insect detritivore g litter{sup -1} d{sup -1}) were 3-fold greater on birch-shade leaves than on birch-sun leaves. Changes in insolation and tree species composition can have important consequences for forest ecosystems, because of effects on litter quality that impact microbial saprobes and, ultimately, invertebrate detritivores. (au)

  5. Environmentally friendly utilization of biomass

    OpenAIRE

    Grimm, Alejandro

    2007-01-01

    The thesis deals with various ways of utilization of biomass. Chapter 1 compares three biomass types: birch wood Betula sp., marine brown alga Fucus vesiculosus, and terrestrial moss Pleurozium schreberi, as precursors for preparation of biosorbents for removal of copper ions from diluted water solutions. Small sample doses (0.5 g/100ml) of the biosorbents prepared from alga and moss enabled more than 90 % removal of Cu (II) ions from diluted water solutions (5-20 mg/l). The sample from birch...

  6. [Selenium in selected species of mushrooms from Poland].

    Science.gov (United States)

    Falandysz, Jerzy

    2003-01-01

    The selenium was quantified in the caps, stalks or a whole fruiting bodies of king bolete (Boletus edulis), brown birch scaber stalk (Leccinum scabrum), parasol mushroom (Macrolepiota procera), fly agaric (Amanita muscaria) and poison pax (Paxillus involutus) collected at the various regions of Poland in 1998-2001. King bolete, parasol mushroom and fly agaric were a much more abundant in selenium than brown birch scaber stalk or poison pax. Some differences were observed between the selenium content of the particular species collected at different sites as well as depending on anatomical part of the fruiting body. PMID:14755851

  7. Tree Productivity and Water Potential Productivity in Returning Farmland to Forest Project in Datong County, Qinghai Province

    Institute of Scientific and Technical Information of China (English)

    Yin Jing; Liu Chenfeng; Zhao Wanqi; He Kangning

    2004-01-01

    From 2002 to 2003, based on the investigation of sample plots and stem analysis of remained plantation communities in the areas of returning farmland to forest in the 1980s in Datong County, Qinghai Province, this paper studies tree productivity and moisture potential productivity of six types of plantations on the land of returning farmland to forest, such as green poplar (Populus cathayana Rehd.) and shrub mixed forest, Asia white birch (Betula platyphylla) and China spruce (Picea asperata) mixed forest, Dahurian larch (Larix gmelinii) pure forest, China spruce pure forest and Asia white birch pure forest and so on. The results show that: in sub-humid region of Loess Plateau, 3 000 trees per hm2 is a proper standard of planting density. Under current condition, the productivity index of green poplar and shrub mixed forest, Asia white birch pure forest, China spruce pure forest, and Asia white birch and China spruce mixed forest with the density of 2 100-3 333 trees per hm2 can serve as potential productivity standard of actual biomass of arbor established forest. In sub-humid area, Thornthwaite Model is adopted to estimate plant climate potential productivity, which is about 8 462 kg·hm-2·a-1. The actual potential water productive efficiency of Purplecone spruce (Picea purpurea) and Asia white birch pure established forest are 17.22 and 22.14 kg·mm-1·hm-2·a-1 respectively, and that of green poplar and shrub mixed established forest, and Asia white birch and China spruce mixed established forest are 21.14 and 19.09 kg·mm-1·hm-2·a-1 respectively. The potential productivity of green poplar and shrub mixed forest, Asia white birch and China spruce mixed forest, China spruce pure forest and Asia white birch pure forest which have grown into forest with the density of 3 000 trees per hm2 have attained or been close to that of local climax community, which is local maximum tree productivity at present. These types of forestation models are the developing

  8. Seasonal variation in food allergy to apple

    DEFF Research Database (Denmark)

    Skamstrup Hansen, K; Vieths, S; Vestergaard, H;

    2001-01-01

    The aim of the study was to investigate the possibility of a seasonal variation in reactivity to apples in 27 birch pollen allergic patients. Before and during the birch pollen season 1998, the patients were subjected to double-blind, placebo-controlled food challenges (DBPCFCs) with grated fresh...... Golden Delicious apple followed by an open food challenge with whole fresh apple. The clinical reactions elicited during the challenges were evaluated both by the patients and the investigators. Moreover, the skin reactivity and the in vitro reactivity to apple were evaluated by skin prick test (SPT...

  9. Epitope grafting, re-creating a conformational Bet v 1 antibody epitope on the surface of the homologous apple allergen Mal d 1

    DEFF Research Database (Denmark)

    Holm, Jens; Ferreras, Mercedes; Ipsen, Henrik;

    2011-01-01

    allergen Malus domestica group 1 (Mal d 1). Engineering of the epitope was accomplished by genetic engineering substituting amino acid residues in Mal d 1 differing between Bet v 1 and Mal d 1 within the epitope defined by the mAb BV16. The kinetic parameters characterizing the antibody binding interaction......Birch-allergic patients often experience oral allergy syndrome upon ingestion of vegetables and fruits, most prominently apple, that is caused by antibody cross-reactivity of the IgE antibodies in patients to proteins sharing molecular surface structures with the major birch pollen group 1 allergen...

  10. 桦褐孔菌的研究进展

    Institute of Scientific and Technical Information of China (English)

    赵芬琴; 朴惠善

    2005-01-01

    桦褐孔菌,学名为Fuscoporia obliqua(Pers:Fr.) Aoshi或Inonotus obliquus(Fr.)Pilat,俗名为Black Birch touchwood,Birch mushroom,C1inker polypore,Tschaga pilz,Crooked schiller—Porling,Kofukisarunokoshikake。属于真菌门、担子菌亚门、层菌纲、非褐菌目(无褶菌目=多孔菌目,多孔菌科)、褐卧孔菌属(纤孔菌属)。

  11. COMPREHENSIVE CHARACTERISTIC OF PINE AND BIRCH SPECIES WITH DIFFERENT SCHEME OF COMBINATION Сравнительная характеристика сосново-березовых культур с различной схемой смешения

    Directory of Open Access Journals (Sweden)

    Shamiryan K. G.

    2012-09-01

    Full Text Available The article presents the characteristics of condition and growth of Pinus sylvestris and Betula Pendula in their cohabitation in poor sand soils (A2 in the condition of some forest enterprises of Voronezh region; the most effective way of combination of this species is revealed

  12. Tartu Waldorf-keskus : arhitektuurne ideekonkurss / Mikk Pärdi

    Index Scriptorium Estoniae

    Pärdi, Mikk

    2013-01-01

    Arhitektuurivõistluse eesmärgiks oli leida terviklik lahendus Tartu Waldorf-keskusele: lasteaed, 12-klassiline kool ja sotsiaalkeskus. Rudolf Steinerist ja lühidalt Waldorf-pedagoogikast. Waldorf-koolide arhitektuurist. Võistlustöödest, I preemia pälvinud tööst "Birch" (Joachim Zimmer, Imme Denker, Saksamaa)

  13. Remission of allergic rhinitis

    DEFF Research Database (Denmark)

    Bødtger, Uffe; Linneberg, Allan

    2004-01-01

    months and s-IgE levels of class 2 or greater against pollen (birch, grass, or mugwort). This was similar for AR to animals (cat or dog) or house dust mites (HDMs). Remission of AR was defined as AR at baseline but no rhinitis symptoms at follow-up and sensitization (s-IgE level class > or =2 at baseline...

  14. Frequency of atopy in the Arctic in 1987 and 1998

    DEFF Research Database (Denmark)

    Krause, Tyra; Koch, Anders; Friborg, Jeppe;

    2002-01-01

    atopy as a positive result in an assay that tests for specific IgE against the eight most common inhalant allergens in one pool (grass, birch, mugwort, dog, cat, horse, Cladosporum herbarum, house dust mite). The frequency of atopy doubled between 1987 (39 [10%] of 392) and 1998 (87 [19%] of 467; risk...

  15. 75 FR 29268 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-05-25

    ... that the community is required either to adopt or to show evidence of having in effect in order to..., 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. ] Sec. 67.4 2. The tables... Washington Street, Pittsfield, IL 62363. Clay County, Indiana, and Incorporated Areas Birch Creek--Pouges...

  16. Development of hypo-allergenic apples: silencing of the major allergen Mal d 1 gene in 'Elstar' apple and the effect of grafting

    NARCIS (Netherlands)

    Krath, B.N.; Eriksen, F.D.; Pedersen, B.H.; Gilissen, L.J.W.J.; Weg, van de W.E.; Dragsted, L.O.

    2009-01-01

    Many people who are allergic to birch pollen are also allergic to apple fruit, due to cross- allergenicity. Since apples are the most extensively consumed fruit in Europe, it is highly relevant to develop a hypo-allergenic apple. Apples with significantly reduced levels of the allergen, Mal d 1, may

  17. AFTER SCHOOL INTEGRATION - WHAT. (PROCEEDINGS OF THE THIRD ANNUAL INVITATIONAL CONFERENCE ON URBAN EDUCATION, MAY 20, 1964).

    Science.gov (United States)

    TANNENBAUM, ABRAHAM J.; AND OTHERS

    CONTENTS INCLUDE THE FOLLOWING SPEECHES--(1) EDUCABILITY AND THE SCHOOL INTEGRATION CRISIS BY DR. MILTON SCHWEBEL, (2) INTELLIGENCE, ETHNIC ORIGINS, AND INTEGRATION BY DR. HERBERT G. BIRCH, (3) INTEGRATION IN EDUCATION - TOWARD WHAT GOALS BY MR. JOHN MORSELL, (4) PROBLEMS IN SOCIAL LEARNING BY DR. ROBERT GREEEN, AND (5) PROBLEMS IN ACADEMIC…

  18. 77 FR 22663 - Asian Longhorned Beetle; Additions to Quarantined Areas in Massachusetts

    Science.gov (United States)

    2012-04-17

    ...;having general applicability and legal effect, most of which are keyed #0;to and codified in the Code of... 17, 2012, we are adopting as a final rule the interim rule published at 76 FR 52541-52543 on August... trees. It attacks many healthy hardwood trees, including maple, horse chestnut, birch, poplar,...

  19. 75 FR 31361 - Proposed Flood Elevation Determinations

    Science.gov (United States)

    2010-06-03

    ... that the community is required either to adopt or to show evidence of having in effect in order to..., 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 2. The tables..., Wiggins, MS 39577. Franklin County, Missouri, and Incorporated Areas Birch Creek Approximately 0.4...

  20. Soil carbon dioxide emissions in response to precipitation frequency in the Loess Plateau, China

    Science.gov (United States)

    Precipitation events can induce episodic CO2 emissions, so called the “Birch Effect”, but how precipitation frequency influences the mechanisms responsible for this effect in dryland cropping systems is not well known. We evaluated the effect of three precipitation frequencies (5-, 10-, and 20-d int...

  1. 黄土丘陵区不同造林模式的土壤效应研究%Soil Effects of Different Afforestation Model in Hilly Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    李金花

    2012-01-01

    分析青海黄土丘陵区相同林龄(8年)的5种造林模式土壤的有机质含量、总孔隙度和微生物总量大小,结果为云杉桦树混交〉桦树〉云杉沙棘混交〉云杉〉沙棘〉农田;各造林模式缓解日温变化效应的大小顺序为云杉桦树混交〉桦树〉云杉沙棘混交〉沙棘〉云杉〉农田。%The effects of soil from different afforestation models in hilly loess plateau were analyzed. The results were as follows: mixture of picea crassifolia and birchbirch 〉mixture of picea crassifolia and hippophae rhamnoides 〉picea crassifolia 〉hippophae rhamnoides〉farmland. The order of easing temperature changes was as follows: mixture of picea crassifo|ia and birchbirch 〉mixture of picea crassifoIia and hippophae rhamnoides ~hippophae rhamnoides 〉picea crassifo|ia 〉 farmland.

  2. Word Misperception, the Neighbor Frequency Effect, and the Role of Sentence Context: Evidence from Eye Movements

    Science.gov (United States)

    Slattery, Timothy J.

    2009-01-01

    An eye movement experiment was conducted to investigate whether the processing of a word can be affected by its higher frequency neighbor (HFN). Target words with an HFN (birch) or without one (spruce) were embedded into 2 types of sentence frames: 1 in which the HFN (birth) could fit given the prior sentence context, and 1 in which it could not.…

  3. The Effects of Divorce and Parental Conflict on Children's Adjustment: A Prospective Study.

    Science.gov (United States)

    Shaw, Daniel

    Replicating the methodology used by Block, Block, and Gjerde (1986), a prospective, longitudinal examination was made of relations between divorce and children's adjustment. Data from the New York Longitudinal Study (NYLS), originally collected by Thomas, Chess, and Birch (1963, 1968, 1977, 1983, 1984) was analyzed. The NYLS assessed children's…

  4. Above-ground and below-ground plant responses to fertilization in two subarctic ecosystems

    NARCIS (Netherlands)

    Veen, G.F.; Sundqvist, Maja K.; Metcalfe, D.; Wilson, S.D.

    2015-01-01

    Soil nutrient supply is likely to change in the Arctic due to altered process rates associated with climate change. Here, we compare the responses of herbaceous tundra and birch forest understory to fertilization, considering both above- and below-ground responses. We added nitrogen and phosphorus t

  5. Assessing five evolving microbial enzyme models against field measurements from a semiarid savannah—What are the mechanisms of soil respiration pulses?

    Science.gov (United States)

    Zhang, Xia; Niu, Guo-Yue; Elshall, Ahmed S.; Ye, Ming; Barron-Gafford, Greg A.; Pavao-Zuckerman, Mitch

    2014-09-01

    Soil microbial respiration pulses in response to episodic rainfall pulses (the "Birch effect") are poorly understood. We developed and assessed five evolving microbial enzyme models against field measurements from a semiarid savannah characterized by pulsed precipitation to understand the mechanisms to generate the Birch pulses. The five models evolve from an existing four-carbon (C) pool model to models with additional C pools and explicit representations of soil moisture controls on C degradation and microbial uptake rates. Assessing the models using techniques of model selection and model averaging suggests that models with additional C pools for accumulation of degraded C in the dry zone of the soil pore space result in a higher probability of reproducing the observed Birch pulses. Degraded C accumulated in dry soil pores during dry periods becomes immediately accessible to microbes in response to rainstorms, providing a major mechanism to generate respiration pulses. Explicitly representing the transition of degraded C and enzymes between dry and wet soil pores in response to soil moisture changes and soil moisture controls on C degradation and microbial uptake rates improve the models' efficiency and robustness in simulating the Birch effect. Assuming that enzymes in the dry soil pores facilitate degradation of complex C during dry periods (though at a lower rate) results in a greater accumulation of degraded C and thus further improves the models' performance. However, the actual mechanism inducing the greater accumulation of labile C needs further experimental studies.

  6. The effect of meteorological factors on airborne Betula pollen concentrations in Lublin (Poland).

    Science.gov (United States)

    Piotrowska, Krystyna; Kubik-Komar, Agnieszka

    2012-12-01

    The present study investigated the pattern of the birch atmospheric pollen seasons in Lublin in the period 2001-2010. Pollen monitoring was conducted using a Lanzoni VPPS 2000 sampler. The atmospheric pollen seasons were determined with the 98% method. Regression analysis was used to determine correlations between meteorological conditions and the pattern of the birch pollen season. On average, the birch pollen season started on 12 April, ended on 13 May, and lasted 32 days. The peak value and the Seasonal Pollen Index showed the greatest variation in particular years. All the seasons were right-skewed. During the study years, a trend was found towards earlier occurrence of the seasonal peak. Regression equations were developed for the following parameters of the atmospheric pollen season: start, duration, peak value and average pollen concentration during the season. The obtained model fit was at a level of 64-81%. Statistical analysis shows that minimum temperature of February and March and total rainfall in June in the year preceding pollen release have the greatest effect on the birch atmospheric pollen season in Lublin. Low temperatures in February promote the occurrence of high pollen concentrations.

  7. Informal learning in the Netherlands

    NARCIS (Netherlands)

    Caniëls, Marjolein; Kirschner, Paul A.

    2011-01-01

    Caniëls, M. C., & Kirschner, P. A. (2010). Informal learning in the Netherlands. In S. Halley, C. Birch, D. Tempelaar, M. McCuddy, N. Hérnandez Nanclares, S. Reeb Grube, W. Gijselaers, B. Rienties, & N. Nelissen (Eds), Proceedings of the 17th EDINEB Conference: Crossing Borders in Education and Work

  8. The Young Child's Temperament: Implications for Child Care.

    Science.gov (United States)

    Anderson-Goetz, Diana; Worobey, John

    1984-01-01

    Reviews approaches to the study of temperament and ways in which knowledge about temperament can be helpful in planning day care and counselling parents. Discusses the nine dimensions of temperament developed by Thomas, Chess, and Birch (1965) to describe infants and children and standardized instruments for measuring temperament developed by…

  9. Re-Seeing "The Mighty": Critically Examining One Film's Representations of Disability in the English Classroom

    Science.gov (United States)

    Maples, Joellen; Arndt, Katrina; White, Julia M.

    2010-01-01

    Films portraying characters with disabilities are often shown in the English classroom. Films such as "Of Mice and Men," "Simon Birch," "To Kill a Mockingbird," "The Hunchback of Notre Dame," "The Glass Menagerie," "Moby Dick," "Gattaca," and "A Beautiful Mind" often show simplistic and stereotypical representations of characters and their…

  10. Experimental Research of Moisture Evaporation Process from Biomass in a Drying Chamber

    Directory of Open Access Journals (Sweden)

    Bulba E.E.

    2015-01-01

    Full Text Available Presented mass evaporation rate hardwood (birch, aspen, maple, poplar derived from experimental studies. The dependence of temperature on evaporation mass rate and calculated the accommodation coefficient for the respective temperature ranges are obtained. Analyzed the temperature of drying conditions relevant species hardwood.

  11. Hazelnut allergy across Europe dissected molecularly : A EuroPrevall outpatient clinic survey

    NARCIS (Netherlands)

    Datema, Mareen R.; Zuidmeer-Jongejan, Laurian; Asero, Riccardo; Barreales, Laura; Belohlavkova, Simona; de Blay, Frederic; Bures, Peter; Clausen, Michael; Dubakiene, Ruta; Gislason, David; Jedrzejczak-Czechowicz, Monika; Kowalski, Marek L.; Knulst, Andre C.; Kralimarkova, Tanya; Le, Thuy-My; Lovegrove, Alison; Marsh, Justin; Papadopoulos, Nikolaos G.; Popov, Todor; del Prado, Nayade; Purohit, Ashok; Reese, Gerald; Reig, Isabel; Seneviratne, Suranjith L.; Sinaniotis, Athanasios; Versteeg, Serge A.; Vieths, Stefan; Zwinderman, Aeilko H.; Mills, Clare; Lidholm, Jonas; Hoffmann-Sommergruber, Karin; Fernandez-Rivas, Montserrat; Ballmer-Weber, Barbara; van Ree, Ronald

    2015-01-01

    Background: Hazelnut allergy is birch pollen-driven in Northern/Western Europe and lipid transfer protein-driven in Spain and Italy. Little is known about other regions and other allergens. Objective: Establishing a molecular map of hazelnut allergy across Europe. Methods: In 12 European cities, sub

  12. Thermodynamic characterization of the PR-10 allergens Bet v 1, Api g 1 and Dau c 1 and pH-dependence of nApi g 1 and nDau c 1

    NARCIS (Netherlands)

    Bollen, M.A.; Wichers, H.J.; Helsper, J.P.F.G.; Savelkoul, H.F.J.; Boekel, van M.A.J.S.

    2010-01-01

    Natural and recombinant Bet v 1, the major birch pollen allergen, and homologous allergens, Api g 1 and Dau c 1, from celery and carrot, respectively, were studied by CD spectroscopy under conditions of varying denaturant concentration, pH and temperature to determine fundamental thermodynamic param

  13. 78 FR 44594 - Notice of Inventory Completion: Washington State Parks and Recreation Commission, Olympia, WA

    Science.gov (United States)

    2013-07-24

    ..., Olympia, WA AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Washington State Parks..., 2013. ADDRESSES: Alicia Woods, Washington State Parks and Recreation Commission, PO Box 42650, Olympia... Washington State Parks and Recreation Commission, Olympia, WA. The human remains were removed from Birch...

  14. Roasted hazelnuts--allergenic activity evaluated by double-blind, placebo-controlled food challenge

    DEFF Research Database (Denmark)

    Hansen, K Skamstrup; Ballmer-Weber, B K; Lüttkopf, D;

    2003-01-01

    Allergy to hazelnuts is a common example of birch pollen related food allergy. Symptoms upon ingestion are often confined to the mouth and throat, but severe systemic reactions have been described in some patients. The aim of the study was to evaluate the reduction in allergenicity by roasting of...

  15. Addressing the Needs of Students with Color Vision Deficiencies in the Elementary School Library

    Science.gov (United States)

    Collins, Karla Bame

    2013-01-01

    Color vision deficiencies affect approximately eight percent of the male population (Birch & Chisholm, 2008; Cole, 2007; Jenny & Kelso, 2007; Neitz & Neitz, 2000), yet the condition is often overlooked in the educational setting despite the pervasiveness of color in the school (Suero et al., 2004). The purpose of this study was to…

  16. The effects of short- and long-term air pollutants on plant phenology and leaf characteristics.

    Science.gov (United States)

    Jochner, Susanne; Markevych, Iana; Beck, Isabelle; Traidl-Hoffmann, Claudia; Heinrich, Joachim; Menzel, Annette

    2015-11-01

    Pollution adversely affects vegetation; however, its impact on phenology and leaf morphology is not satisfactorily understood yet. We analyzed associations between pollutants and phenological data of birch, hazel and horse chestnut in Munich (2010) along with the suitability of leaf morphological parameters of birch for monitoring air pollution using two datasets: cumulated atmospheric concentrations of nitrogen dioxide and ozone derived from passive sampling (short-term exposure) and pollutant information derived from Land Use Regression models (long-term exposure). Partial correlations and stepwise regressions revealed that increased ozone (birch, horse chestnut), NO2, NOx and PM levels (hazel) were significantly related to delays in phenology. Correlations were especially high when rural sites were excluded suggesting a better estimation of long-term within-city pollution. In situ measurements of foliar characteristics of birch were not suitable for bio-monitoring pollution. Inconsistencies between long- and short-term exposure effects suggest some caution when interpreting short-term data collected within field studies.

  17. Nonvolatile dichloromethane extractives of Gmelina arborea

    Energy Technology Data Exchange (ETDEWEB)

    Ukkonen, K.

    1982-02-01

    In pulping it is important to know how lipophilic extractives will behave and so avoid pitch problems. Experiments on Gmelina wood delivered from Brazil in 1978 are described, using dichloromethane extractives to give sufficient information about the lipophilic extractives. The behavior of Gmelina extracts in kraft pulping was compared to that of birch extracts and was found to be similar. (Refs. 10).

  18. Highlights of forest pest conditions in the maritimes at the end of July, 1993. Technical note No. 286. Annual publication

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, J.E.

    1993-01-01

    This note describes forest pest conditions in the Maritimes at the end of July, 1993. It discusses diseases and pests found including forest tent caterpiller, gypsy moth, fall webworm, spruce budworm, and wind damage. Others include eastern blackheaded budworm, elm leafroller, alder flea beetle, birch leafminers, oak olethreutid leafroller, yellowheaded spruce sawfly, and spruce spider mite.

  19. ФАКТИЧЕСКАЯ ГОРИМОСТЬ ЛЕСОВ ЛЕСНИЧЕСТВ ПРИОБСКОГО ВОДООХРАННОГО СОСНОВО - БЕРЕЗОВОГО ЛЕСОХОЗЯЙСТВЕННОГО РАЙОНА АЛТАЙСКОГО КРАЯ

    OpenAIRE

    Шубин, Д. А.

    2009-01-01

    The data of 59 - years observation of the guantity of forest fires and their burnt area in the forest of forest area of By-Ob water-conservatory pine-birch forest farming area in the Altai territory, the analysis of factual forest burning ability is carried out for 5-years periods of time, specific burning ability is calculated.

  20. ВОРОБЬИНЫЕ ПТИЦЫ ДУБРАВ И БЕРЕЗНЯКОВ ЕЛЕНСКОГО ЛЕСНИЧЕСТВА КАЛУЖСКОЙ ОБЛАСТИ

    OpenAIRE

    КИСТЕРНЫЙ Г.А.; ЛЕВКИНА Е.Н.

    2008-01-01

    Distribution of sparrow birds in afforestations is investigated. The specific structure of complexes in complex oak groves and birch forests of part Elenskiy of a forest area of the Kaluga area is established. Parameters of density of settlement of birds during the nested period depending on conditions of wood habitats are analysed.

  1. Indoleamine 2,3-dioxygenase expression in patients with allergic rhinitis: a case-control study

    Directory of Open Access Journals (Sweden)

    Luukkainen Annika

    2011-12-01

    Full Text Available Abstract Background Indoleamine 2,3-dioxygenase (IDO is a tryptophan catalyzing enzyme. It has been suggested that it has a role in lower airway allergic inflammations, but its role in allergic rhinitis has not been investigated. Objective Our aim was to evaluate the expression of IDO in the nasal mucosa of allergic rhinitis patients allergic to birch pollen during peak exposure to birch pollen allergen and compare it to non-atopic patients. Methods IDO expression was immunohistochemically evaluated from nasal specimens obtained in- and off-season from otherwise healthy non-smoking volunteers both allergic to birch pollen (having mild or moderate allergic rhinoconjunctivitis and non-allergic controls. Results: The IDO expression levels were low in healthy controls and remained low also in patients allergic to birch pollen. There were no differences in the expression of IDO in- and off-season in either healthy or allergic subjects. Conclusions There is a controversy in the role of IDO in upper and lower airways during allergic airway disease. It seems that IDO is associated to allergic inflammations of the lower airways, but does not have a local role in the nasal cavity at least in mild or moderate forms of allergic rhinitis.

  2. The effect of different mulches on the growth and yield of organically grown strawberry

    OpenAIRE

    Kivijärvi, Pirjo; Prokkola, Soile

    2003-01-01

    Different mulches were studied in field trials over a three-year period under organic production in Mikkeli and Ruukki. The mulching materials were black plastic, flax fibre mat (woodchips+buckwheat husk in 2002), green mass, straw, buckwheat husk, birch woodchips and pine woodchips.

  3. The effect of different mulches on yield, fruit quality and strawberry mite in organically grown strawberry

    OpenAIRE

    Kivijärvi, Pirjo; Parikka, Päivi; Tuovinen, Tuomo

    2002-01-01

    An organic strawberry field experiment was started in 2000 at MTT Ecological Production in Mikkeli to study the influence of mulching materials on the growth, yield, microbiological fruit quality and strawberry mite. Mulching materials are black plastic, flax fibre mat, green mass, barley straw, buckwheat husk as well as pine and birch woodchips.

  4. Be Water Wise

    OpenAIRE

    1983-01-01

    This 45-page book contains activities for grades six through 12 on water conservation, water in the environment, and water and wastewater treatment. Accompanied by Instructor's guide to Be water-wise, written by Alvin M. Pettus and edited by Sandra K. Birch. Reprinted in 1985 and 1988.

  5. Expression of Toll-like receptors in nasal epithelium in allergic rhinitis.

    Science.gov (United States)

    Renkonen, Jutta; Toppila-Salmi, Sanna; Joenväärä, Sakari; Mattila, Pirkko; Parviainen, Ville; Hagström, Jaana; Haglund, Caj; Lehtonen, Mikko; Renkonen, Risto

    2015-08-01

    Toll-like receptors (TLRs) are important in barrier homeostasis, but their role in airborne allergies is not fully understood. The aim was to evaluate baseline and allergen-induced expression of TLR proteins in nasal epithelium during allergic rhinitis. Nineteen otherwise healthy non-smoking volunteers both allergic to birch pollen and non-allergic controls were enrolled. We took nasal biopsies before and after off-seasonal intranasal birch pollen or diluent challenge. The expression of epithelial TLR1-7, TLR9-10, and MyD88 proteins was immunohistochemically evaluated from the nasal biopsies. The TLR1-3 and TLR5-10 mRNAs were observed by RNA-microarray. Baseline epithelial expression of TLR proteins was wide and identical in controls and atopics. After off-seasonal intranasal birch pollen challenge, a negative change in the expression score of TLR1 and TLR6 proteins was detected in the atopic group. TLR mRNA expression was not affected by birch pollen challenge. Nasal epithelium seems to express all known TLRs. The mechanisms by which TLR1, and TLR6 proteins could affect pollen allergen transport need further studies.

  6. Rapid atmospheric CO2 changes associated with the 8,200-years-B.P. cooling event

    NARCIS (Netherlands)

    Wagner, F.; Aaby, B.; Visscher, H.

    2002-01-01

    By applying the inverse relation between numbers of leaf stomata and atmospheric CO2 concentration, stomatal frequency analysis of fossil birch leaves from lake deposits in Denmark reveals a century-scale CO2 change during the prominent Holocene cooling event that occurred in the North Atlantic regi

  7. The role of summer precipitation and summer temperature in establishment and growth of dwarf shrub Betula nana in northeast Siberian tundra

    DEFF Research Database (Denmark)

    Li, Bingxi; Heijmans, Monique M P D; Berendse, Frank;

    2016-01-01

    It is widely believed that deciduous tundra-shrub dominance is increasing in the pan-Arctic region, mainly due to rising temperature. We sampled dwarf birch (Betula nana L.) at a northeastern Siberian tundra site and used dendrochronological methods to explore the relationship between climatic...

  8. Analyzing carbon losses from dry soils after precipitation pulses by stable carbon isotopes

    Science.gov (United States)

    Unger, Stephan; Máguas, Cristina; Santos-Pereira, João.; Werner, Christiane

    2010-05-01

    Rain events after drought periods strongly increase soil respiration (Birch effect) and affect plant activity, and thus, may influence the isotopic signal of ecosystem respiration. These CO2-pulses may largely affect the C-balance of arid and semi-arid systems. Here, we evaluate the origins of the Birch effect in a Mediterranean forest and its influence on the isotopic signal of ecosystem (δ13CR) and soil respiration (δ13CSoil). We conducted artificial rain pulses in May and August 2005 and estimated δ13CSoil on intact vegetation, bare and root-free soil in response to watering. After watering in May δ13CSoil showed strong enrichment (-18) and a rapid return to initial values (-27). This transient enrichment was smaller in August than in May (ca. -22). Further, we compared δ13CR and δ13CSoil after first natural rains in October 2005, where both revealed a good relationship over the diurnal and the fortnight cycle. We hypothesize that the 'Birch effect' immediately after irrigation is the result of a hypo-osmotic stress response of the soil microbial community: during sudden moisture changes enriched osmoregulants are rapidly released and mineralized by the soil microbes to avoid cell lysis. After the pulse soil respiration followed a common moisture response. The overall impact of the Birch effect on C-sequestration will depend on both timing and frequency of the rains and thus, on whether the respired CO2 source is microbial or soil organic matter carbon.

  9. Crystal structure of peanut (Arachis hypogaea) allergen Ara h 5

    Science.gov (United States)

    Profilins from numerous species are known to be allergens, including food allergens, such as peanut (Arachis hypogaea) allergen Ara h 5, and pollen allergens, such as birch allergen Bet v 2. Patients with pollen allergy can also cross-react to peanut. Structural characterization of allergens will al...

  10. Effects of increased temperature and CO{sub 2} on soil quality

    Energy Technology Data Exchange (ETDEWEB)

    Ogner, G.

    1996-03-01

    This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. The Norwegian Forest Research Institute has studied the effects of increased CO{sub 2} and temperature on forest soil, soil leachate and plants in an open top chamber experiment. The purpose was to analyze the changes in soil parameters and the leaching of elements. Nitrate and aluminium received special attention. The growth of Norway spruce and birch was followed, and its impact on the soil parameters. Preliminary results indicate that the temperature increase of the soil and consequently an increased turnover of soil organic matter had the major effect on the quality of soil leachates. CO{sub 2} was less important. Leaching of NO{sub 3}{sup -} was high from control lysimeters with moss cover. Lysimeters with birch hardly leached NO{sub 3}{sup -} at all. Spruce is in an intermediate position. Increased leaching of Al{sup n+} is found for moss lysimeters. Leachates from birch lysimeters have high concentrations of Al{sup n+} only at the end of the growth seasons. Plant growth is to some extent increased by the CO{sub 2} treatment. Birch grew well in all lysimeters and all treatments, spruce developed clear symptoms of stress. This result does not fit with the increased availability of nutrients in soil solution

  11. Effects of elevated CO2 leaf diets on gypsy moth (Lepidoptera: Lymantriidae) respiration rates.

    Science.gov (United States)

    Foss, Anita R; Mattson, William J; Trier, Terry M

    2013-06-01

    Elevated levels of CO2 affect plant growth and leaf chemistry, which in turn can alter host plant suitability for insect herbivores. We examined the suitability of foliage from trees grown from seedlings since 1997 at Aspen FACE as diet for the gypsy moth (Lymantria dispar L.) Lepidoptera: Lymantriidae: paper birch (Betula papyrifera Marshall) in 2004-2005, and trembling aspen (Populus tremuloides Michaux) in 2006-2007, and measured consequent effects on larval respiration. Leaves were collected for diet and leaf chemistry (nutritional and secondary compound proxies) from trees grown under ambient (average 380 ppm) and elevated CO2 (average 560 ppm) conditions. Elevated CO2 did not significantly alter birch or aspen leaf chemistry compared with ambient levels with the exception that birch percent carbon in 2004 and aspen moisture content in 2006 were significantly lowered. Respiration rates were significantly higher (15-59%) for larvae reared on birch grown under elevated CO2 compared with ambient conditions, but were not different on two aspen clones, until larvae reached the fifth instar, when those consuming elevated CO2 leaves on clone 271 had lower (26%) respiration rates, and those consuming elevated CO2 leaves on clone 216 had higher (36%) respiration rates. However, elevated CO2 had no apparent effect on the respiration rates of pupae derived from larvae fed either birch or aspen leaves. Higher respiration rates for larvae fed diets grown under ambient or elevated CO2 demonstrates their lower efficiency of converting chemical energy of digested food stuffs extracted from such leaves into their biosynthetic processes.

  12. Upgrading of raw tall oil soap into fuel oils and lubricants; Raakasuovan jalostus poltto- ja voiteluoeljyksi

    Energy Technology Data Exchange (ETDEWEB)

    Oasmaa, A.; Arpiainen, V.; McKeough, P.; Tapola, E.; Haekkinen, R.; Kuoppala, E.; Koskela, K. [VTT Energy, Jyvaeskylae (Finland). Energy Production Technologies

    1997-12-01

    Thermochemical processing of tall oil soap originating from various mixtures of birch and pine has been experimentally investigated. The organic matter of tall oil soap, which is a by- product of Kraft pulping, originates mainly from wood extractives. Conventional processing of tall oil soap involves acidulation with sulphuric acid to yield crude tall oil and subsequent distillation of the oil at centralised refineries. Because tall oil originating from birch wood is far less valuable than that from pine, there is an economic incentive in the Nordic countries to develop alternative conversion processes for the tall oil soap produced at pulp mills where birch is widely used as feedstock. Furthermore, thermochemical processing of tall oil soap does not introduce sulphur into the chemical recovery cycle. This would be a significant advantage in future mills employing closure of water circuits and/or sulphur-free pulping. In small-scale experiments tall oil soaps from wood mixtures with high birch content have been processed using both liquid-phase thermal treatment and pyrolysis. The liquid-phase thermal treatment at 450 deg C under a nitrogen atmosphere yielded a good-quality oil product at high yield (about 50 % of the energy content of the tall oil soap). In the atmospheric pyrolysis of birch tall oil soap a separation of inorganic and organic constituents was obtained. The energy value of the product gases was high. Both processes are promising, but the pyrolysis alternative has the greater economic potential, providing that the promising preliminary experimental results have given a true picture of the performance of the full-scale pyrolysis process. (orig.)

  13. Effects of elevated atmospheric CO2 and/or O3 on intra- and interspecific competitive ability of aspen.

    Science.gov (United States)

    Kubiske, M E; Quinn, V S; Marquardt, P E; Karnosky, D F

    2007-03-01

    Three model communities of trembling aspen (monoculture, and mixed with either paper birch or sugar maple) were grown for seven years in elevated atmospheric CO(2) and O(3) using Free Air CO(2) Enrichment (FACE) technology. We utilized trends in species' importance, calculated as an index of volume growth and survival, as indications of shifting community composition. For the pure aspen communities, different clones emerged as having the highest change in relative importance values depending on the pollutant exposure. In the control and elevated CO(2) treatments, clone 42E was rapidly becoming the most successful clone while under elevated O(3), clone 8 L emerged as the dominant clone. In fact, growth of clone 8 L was greater in the elevated O(3) treatment compared to controls. For the mixed aspen-birch community, importance of aspen and birch changed by - 16 % and + 62 %, respectively, in the controls. In the treatments, however, importance of aspen and birch changed by - 27 % and + 87 %, respectively, in elevated O(3), and by - 10 % and + 45 %, respectively, in elevated CO(2). Thus, the presence of elevated O(3) hastened conversion of stands to paper birch, whereas the presence of elevated CO(2) delayed it. Relative importance of aspen and maple changed by - 2 % and + 3 %, respectively, after seven years in the control treatments. But in elevated O(3), relative importance of aspen and maple changed by - 2 % and + 5 %, respectively, and in elevated CO(2) by + 9 and - 20 %, respectively. Thus, elevated O(3) slightly increases the rate of conversion of aspen stands to sugar maple, but maple is placed at a competitive disadvantage to aspen under elevated CO(2).

  14. [Comparison of component from different species of Inonotus obliquus].

    Science.gov (United States)

    Guo, Xiao-Fan; Piao, Zhong-Yun

    2014-10-01

    In this paper, water content, mineral element and active ingredient concentration on fifteen Inonotus obliquus which comes from all over the world were studied. In the aspect of water content, the free water content of Finnish birch was the highest, reaching 77.21%, significantly better than that of other strains. The free water content of JL04 is the lowest, only 54.6%. The bound water content of HLJ01 which from Heilongjiang is the highest, reaching 10. 74% , significant differences among other strains. The bound water content of Birch Russia was the lowest. In the aspect of mineral element, the calcium content of NBRC9788 was the high- est (3.49 mg · g(-1)), significantly better than other strains. The second was Finnish birch. The lowest was CX02. The phosphorus content of NBRC9788 was the highest (210.12 μg · g(-1)), significantly superior to other strains. The lowest was JL04. In the aspect of active ingredient concentration, the triterpenoids content of HLJ01 was highest (23.7 mg · g(-1)), significantly better than other strains. It was good strains for biological products research and development and then was Finnish birch. The betulin content of MAFF420165 and MAFF420308 was low, they were not suitable for production. The polysaccharide content of Finnish birch was the highest (9.7%), significantly better than the other strains, it is one of the most ideal and good strains to develop polysaccharide. The polysaccharide content from MAFF420308 and MAFF420256 was 1.2%, lower than other strains. We suggest that avoid using these strains in the study of polysaccharide product development. PMID:25751946

  15. Assessing the Effect of Leaf Litter Diversity on the Decomposition and Associated Diversity of Fungal Assemblages

    Directory of Open Access Journals (Sweden)

    Jing Gao

    2015-07-01

    Full Text Available Although the effect of litter mixture on decomposition has been well documented, few studies have examined the relationships between richness and relative abundance of leaf species in litter mixture and changes in universal fungal communities during the decomposition process in temperate forests. In this study, we used the litterbag method and included three leaf litter species, i.e., aspen (Populus davidiana Dode, birch (Betula platyphylla Sukaczev and oak (Quercus mongolica Fischer ex Ledebour, to investigate the mass loss rate and diversity of universal fungal communities in each litter treatment, which were sampled in situ after 180, 240, 300 and 360 days of decomposition (between 2012 and 2013 in broadleaved mixed forests in Chinese temperate forests. Eight mixture proportions were examined: pure aspen litter (10A, pure birch litter (10B, pure oak litter (10O, 50% aspen litter mixed with 50% birch litter (5A:5B, 50% aspen litter mixed with 50% oak (5A:5O, 50% birch litter mixed with 50% oak litter (5B:5O, 10% birch litter mixed with 80% aspen litter and 10% oak litter (1B:8A:1O, 30% birch litter mixed with 40% aspen litter and 30% oak litter (3B:4A:3O. Over 360 days of decomposition, approximately 46.6%, 43.6%, 28.0%, 54.4%, 40.2%, 39.5%, 54.5% and 49.46% of litter mass was lost from 10A, 10B, 10O, 5A:5B, 5A:5O, 5B:5O, 1B:8A:1O and 3B:4A:3O, respectively. In addition, the number of fungal denaturing gradient gel electrophoresis (DGGE bands showed a positive correlation with mass loss rate, indicating a positive feedback between leaf litter decomposition and universal fungal communities in the leaf litter. The results revealed that the 5A:5B, 1B:8A:1O and 3B:4A:3O litter mixtures had a synergistic effect on the litter mixture, while the 5A:5O and 5B:5O litter mixtures had a nearly neutral effect on the litter mixture. Thus, leaf litter species composition and relative abundance seem to be more important than leaf litter richness in driving

  16. 青海湟水河流域不同退耕还林模式水文效应%Hydrological Effects of Different Sloping Land Conversion Program Models in Huangshui River Watershed of Qinghai Province

    Institute of Scientific and Technical Information of China (English)

    董旭

    2011-01-01

    基于野外采样、定点观测和室内实验,研究青海湟水河流域不同退耕还林模式水文效应,结果表明:不同林分类型枯落物有效持水性大小顺序为云杉桦树混交〉桦树〉云杉〉沙棘,其林下土壤持水性大小顺序为云杉桦树混交〉沙棘〉桦树〉云杉〉农田;森林土壤是森林生态系统水文效应的主体,枯落物和土壤总持水性大小顺序为云杉桦树混交〉沙棘〉桦树〉云杉〉农田。不同林分类型枯落物持水量决定于枯落物蓄积量和自然含水率,其林下土壤持水量决定于土壤非毛细管孔隙度。%Based on field investigation conversion program models in Huangsh and experimental data, hydrological effects from different sloping land ui river watershed of Qinghai province were studied, the results showed that : the descend order of different forest litter' s water holding capacity was as flows, mixture of picea crassifolia and birch, birch, pieea crassifolia, hippophae rhanmoides ; the descend order of different forest soil' s was as flows, mixture of picea crassifolia and birch, hippophae rhamnoides, birch, picea crassifolia, farmland ; forest soil was the principal part of forest ecosystem hydrological effects ;the descend order of forest litter and soilg to- tal water holding capacity was as flows, mixture of picea crassifolia and birch, hippophae rhamnoides, birch, picea crassifolia, farmland. Litter storage and its natural moisture content were the main reason of water holding capacity, non-capillary porosity of soil was the main reason of forest water holding capacity.

  17. Transfer of Chemically Modified Graphene with Retention of Functionality for Surface Engineering.

    Science.gov (United States)

    Whitener, Keith E; Lee, Woo-Kyung; Bassim, Nabil D; Stroud, Rhonda M; Robinson, Jeremy T; Sheehan, Paul E

    2016-02-10

    Single-layer graphene chemically reduced by the Birch process delaminates from a Si/SiOx substrate when exposed to an ethanol/water mixture, enabling transfer of chemically functionalized graphene to arbitrary substrates such as metals, dielectrics, and polymers. Unlike in previous reports, the graphene retains hydrogen, methyl, and aryl functional groups during the transfer process. This enables one to functionalize the receiving substrate with the properties of the chemically modified graphene (CMG). For instance, magnetic force microscopy shows that the previously reported magnetic properties of partially hydrogenated graphene remain after transfer. We also transfer hydrogenated graphene from its copper growth substrate to a Si/SiOx wafer and thermally dehydrogenate it to demonstrate a polymer- and etchant-free graphene transfer for potential use in transmission electron microscopy. Finally, we show that the Birch reduction facilitates delamination of CMG by weakening van der Waals forces between graphene and its substrate. PMID:26784372

  18. The value of pre- and co-seasonal sublingual immunotherapy in pollen-induced allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Demoly, Pascal; Calderon, Moises A; Casale, Thomas B;

    2015-01-01

    of poor efficacy or safety. The results of recent double-blind, placebo-controlled, randomized clinical trials show that pre- and co-seasonal SLIT is safe and effective in patients with AR induced by grass pollen (treated with a tablet formulation) or by birch pollen (treated with a liquid formulation......). Progress in SLIT has been made in defining the optimal dose of major allergen, the administration frequency (daily), the duration of pre-seasonal treatment (four months) and the number of treatment seasons (at least three). Post-marketing, "real-life" trials of pre- and co-seasonal birch or grass pollen...... SLIT regimens have confirmed the efficacy and safety observed in the clinical trials. In the treatment of pollen-induced AR, pre- and co-seasonal SLIT regimens appear to be at least as effective and safe as perennial SLIT regimens, and are associated with lower costs and good compliance. Good...

  19. Modeling the Emission of CO from Wood Fires using Detailed Chemical Kinetics

    DEFF Research Database (Denmark)

    Dederichs, Anne

    Carbon monoxide is treated as one of the most common and dangerous of gases evolving in fires. Modeling the formation of the toxic gas CO from in fire enclosures using detailed chemical kinetics is the topic of this manuscript. A semi-empirical model is developed to study the formation of CO from...... birch wood using detailed chemical kinetics on the combustion of pyrolysis gas from birch wood. The composition of the pyrolysis gas is taken from the experiment by Zanzi and coworkers. The numerical model applies a counter flow configuration involving 84 chemical species and 804 reactions. Hence......, the model separately treats the process of pyrolysis and combustion. For under ventilated conditions and at high temperatures during pyrolysis it is found that the process of pyrolysation strongly influences the formation of CO in fire. CO2 follows the same trend....

  20. Universal P-V-T Equation of States; Periclase is an Example

    CERN Document Server

    Garai, Jozsef

    2008-01-01

    Universal P-V-T equations of states are derived using the isothermal expressions of Birch-Murnaghan and the Vinet EoSs. These equations along with the EoS [Garai, 2007] are tested against the experiments of Periclase. The root-main-square (RMS) misfits of the universal Birch-Murnaghan and Vinet EoSs are 0.33 GPa, 0.32 GPa respectively. The RMS misfits of the EoS [Garai, 2007] are 0.021 cm3, 0.35 GPa and 66 K for the molar volume, pressure and temperature respectively. The determined single sets of parameters of the EoSs are valid through the entire pressure and temperature range of the mantle.

  1. Tree Species Establishment in Urban Forest in Relation to Vegetation Composition, Tree Canopy Gap Area and Soil Factors

    Directory of Open Access Journals (Sweden)

    Ilze Jankovska

    2015-12-01

    Full Text Available The study of density and growth of pine, birch and oak seedlings and saplings in canopy gaps in the urban boreal forest in Riga, Latvia, indicates that natural regeneration can increase diversity in small gaps caused by tree mortality, and can ensure conversion from even-aged pine forest. Abundant regeneration in small gaps showed that light (gap area was only one of the factors affecting tree regeneration in the gaps. The depth of the O layer and pH were suggested to be important factors for the establishment and growth of pine and birch. For oak, the main factors for establishment and growth were favorable moisture, higher pH and N concentration. Knowledge of ecological factors affecting the establishment of seedlings and growth of saplings of the most common trees species in the urban boreal forest is needed to predict successional trajectories and to aid management.

  2. Phosphonated nanocelluloses from sequential oxidative-reductive treatment-Physicochemical characteristics and thermal properties.

    Science.gov (United States)

    Sirviö, Juho Antti; Hasa, Tapani; Ahola, Juha; Liimatainen, Henrikki; Niinimäki, Jouko; Hormi, Osmo

    2015-11-20

    Nanocellulosic materials with good thermal stability are highly desirable for applications, such as reinforcement and filler agents in composites. In the present work, phosphonated cellulose was utilized to obtain nanocelluloses with good thermal stability and potential intumescent properties. Phosphonated cellulose was synthetized from birch pulp via sequential periodate oxidation and reductive amination using a bisphosphonate group-containing amine, sodium alendronate, as a phosphonating reagent. After high-pressure homogenization, bisphosphonate cellulose nanofibres or nanocrystals were obtained, depending on the initial oxidation degree. Nanofibres had a typical diameter of 3.8nm and length of several micrometers, whereas nanocrystals exhibited a width of about 6nm and an average length of 103-129nm. All nanocelluloses exhibited cellulose I crystalline structures and high transparency in water solutions. Phosphonated nanocelluloses exhibited good thermal stability and a greater amount of residual char was formed at 700°C compared to birch pulp and mechanically produced, non-chemically modified NFC. PMID:26344310

  3. Comparison and analysis of the main technological factors of influencing mechanical properties of scrimber and PSL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The main mechanical properties of scrimber and Parallel Strand Lumber (PSL) were researched through technological test. Experimental materials of scrimber are small log of Aspen, Dahurian larch and Birch. Experimental materials of PSL come from fishtail veneer strips at plywood plant of Aspen and Birch. In the laboratory conditions low quality small log and wood residues can yield scrimber and PSL with high strength. After the technological conditions of scrimber were compared with that of PSL, the main factors of influencing their properties were separately pointed out and the reasons influencing properties have been analyzed in this paper. The results showed that the hot-pressing pressure is an important technological factor for scrimber. The ratio of veneer-strand length to thickness is a key technological factor for PSL.

  4. Glued Joint Behavior of Ribs for Wood-Based Composite Plates

    Science.gov (United States)

    Frolovs, G.; Rocens, K.; Sliseris, J.

    2015-11-01

    This article presents experimental investigations of composite sandwich plywood plates with cell type core and their connections between skin layers of birch plywood and a core of straight and curved plywood honeycomb-type ribs. This shape of core ribs provides several improvements for these plates in the manufacturing process as well as improves the mechanical properties of plywood plates. This specific form of ribs allows simplifying the manufacturing of these plates although it should be detailed and improved. The most typical cases (series of specimens) were compared to the results obtained from FEM (ANSYS) simulations. All thicknesses of elements are chosen according to plywood supplier assortment. Standard birch plywood (Riga Ply) plates were used - three layer plywood was chosen for skin elements (Surfaces) and three or five layer plywood was chosen for edge elements. Different bond pressures were taken to compare their influence on joint strength and stiffness.

  5. Changes in vegetation cover and composition in the Swedish mountain region.

    Science.gov (United States)

    Hedenås, Henrik; Christensen, Pernilla; Svensson, Johan

    2016-08-01

    Climate change, higher levels of natural resource demands, and changing land use will likely lead to changes in vegetation configuration in the mountain regions. The aim of this study was to determine if the vegetation cover and composition have changed in the Swedish region of the Scandinavian Mountain Range, based on data from the long-term landscape biodiversity monitoring program NILS (National Inventory of Landscapes in Sweden). Habitat type and vegetation cover were assessed in 1740 systematically distributed permanent field plots grouped into 145 sample units across the mountain range. Horvitz-Thompson estimations were used to estimate the present areal extension of the alpine and the mountain birch forest areas of the mountain range, the cover of trees, shrubs, and plants, and the composition of the bottom layer vegetation. We employed the data from two subsequent 5-year monitoring periods, 2003-2007 and 2008-2012, to determine if there have been any changes in these characteristics. We found that the extension of the alpine and the mountain birch forest areas has not changed between the inventory phases. However, the total tree canopy cover increased in the alpine area, the cover of graminoids and dwarf shrubs and the total cover of field vegetation increased in both the alpine area and the mountain birch forest, the bryophytes decreased in the alpine area, and the foliose lichens decreased in the mountain birch forest. The observed changes in vegetation cover and composition, as assessed by systematic data in a national and regional monitoring scheme, can validate the results of local studies, experimental studies, and models. Through benchmark assessments, monitoring data also contributes to governmental policies and land-management strategies as well as to directed cause and effect analyses. PMID:27387190

  6. Life-history strategies affect aphid preference for yellowing leaves

    OpenAIRE

    Holopainen, Jarmo K.; Semiz, Gürkan; Blande, James D

    2009-01-01

    According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a consequence of root anoxia. The number of adults and nymphs of the birch-feeding specialist aphids ...

  7. The finding of a paleo-spruce timber in Hunshandak sandy land and its paleoecological significance

    Institute of Scientific and Technical Information of China (English)

    崔海亭; 刘鸿雁; 腰希申

    1997-01-01

    A paleo-sprucc (Picea jezoensis) timber dated to (10 040 + 100) a B. P. was found in the Hunshan-dak sandy land, Inner Mongolia, which is also one of the oldest timber found in China. Pollen and mammal fossil further evidence that theropencedrymion dominated by birch and spruce existed in this area in the late period of the earlier Holocene. This finding has great significance for the analysis of paleoclimate, paleovegetation and landscape development in this area.

  8. Implementation and Comparison of Acoustic Travel-Time Measurement Procedures for the Helioseismic and Magnetic Imager Time-Distance Helioseismology Pipeline

    Science.gov (United States)

    Couvidat, S.; Zhao, J.; Birch, A. C.; Kosovichev, A. G.; Duvall, T. L., Jr.; Parchevsky, K.; Scherrer, P. H.

    2009-01-01

    The Helioseismic and Magnetic Imager (HMI) instrument on board the Solar Dynamics Observatory (SDO) satellite is designed to produce high-resolution Doppler velocity maps of oscillations at the solar surface with high temporal cadence. To take advantage of these high-quality oscillation data, a time-distance helioseismology pipeline has been implemented at the Joint Science Operations Center (JSOC) at Stanford University. The aim of this pipeline is to generate maps of acoustic travel times from oscillations on the solar surface, and to infer subsurface 3D flow velocities and sound-speed perturbations. The wave travel times are measured from cross covariances of the observed solar oscillation signals. For implementation into the pipeline we have investigated three different travel-time definitions developed in time-distance helioseismology: a Gabor wavelet fitting (Kosovichev and Duvall, 1997), a minimization relative to a reference cross-covariance function (Gizon and Birch, 2002), and a linearized version of the minimization method (Gizon and Birch, 2004). Using Doppler velocity data from the Michelson Doppler Imager (MDI) instrument on board SOHO, we tested and compared these definitions for the mean and difference travel-time perturbations measured from reciprocal signals. Although all three procedures return similar travel times in a quiet Sun region, the method of Gizon and Birch (2004) gives travel times that are significantly different from the others in a magnetic (active) region. Thus, for the pipeline implementation we chose the procedures of Kosovichev and Duvall (1997) and Gizon and Birch (2002). We investigated the relationships among these three travel-time definitions, their sensitivities to fitting parameters, and estimated the random errors they produce

  9. Implementation and Comparison of Acoustic Travel-Time Measurement Procedures for the Solar Dynamics Observatory-Helioseismic and Magnetic Imager Time-Distance Helioseismology Pipeline

    Science.gov (United States)

    Couvidat, S.; Zhao, J.; Birch, A. C.; Kosovichev, A. G.; Duvall, Thomas L., Jr.; Parchevsky, K.; Scherrer, P. H.

    2010-01-01

    The Helioseismic and Magnetic Imager (HMI) instrument onboard the Solar Dynamics Observatory (SDO) satellite is designed to produce high-resolution Doppler-velocity maps of oscillations at the solar surface with high temporal cadence. To take advantage of these high-quality oscillation data, a time - distance helioseismology pipeline (Zhao et al., Solar Phys. submitted, 2010) has been implemented at the Joint Science Operations Center (JSOC) at Stanford University. The aim of this pipeline is to generate maps of acoustic travel times from oscillations on the solar surface, and to infer subsurface 3D flow velocities and sound-speed perturbations. The wave travel times are measured from cross-covariances of the observed solar oscillation signals. For implementation into the pipeline we have investigated three different travel-time definitions developed in time - distance helioseismology: a Gabor-wavelet fitting (Kosovichev and Duvall, SCORE'96: Solar Convection and Oscillations and Their Relationship, ASSL, Dordrecht, 241, 1997), a minimization relative to a reference cross-covariance function (Gizon and Birch, Astrophys. J. 571, 966, 2002), and a linearized version of the minimization method (Gizon and Birch, Astrophys. J. 614, 472, 2004). Using Doppler-velocity data from the Michelson Doppler Imager (MDI) instrument onboard SOHO, we tested and compared these definitions for the mean and difference traveltime perturbations measured from reciprocal signals. Although all three procedures return similar travel times in a quiet-Sun region, the method of Gizon and Birch (Astrophys. J. 614, 472, 2004) gives travel times that are significantly different from the others in a magnetic (active) region. Thus, for the pipeline implementation we chose the procedures of Kosovichev and Duvall (SCORE'96: Solar Convection and Oscillations and Their Relationship, ASSL, Dordrecht, 241, 1997) and Gizon and Birch (Astrophys. J. 571, 966, 2002). We investigated the relationships among

  10. Long-term effect of different planting proportions on forest landscape in Great Xing'an Mountains, Northeast China after the catastrophic fire in 1987

    Institute of Scientific and Technical Information of China (English)

    WANG Xugao; LI Xiuzhen; HE Hongshi; XIE Fuju

    2007-01-01

    A landscape model(LANDIS)was used to study the long-term forest dynamics under five planting types (100% larch(P1);70% larch and 30% Mongolian Scotch pine(Pinus sylvestris var.mongolica)(P2);50% larch and 50% Mongolian Scotch pine(P3);30% larch and 70% Mongolian Scotch pine(P4),100% Mongolian Scotch pine (P5)),which were also employed in severely burned area under current planting intensity,and under natural regeneration(as a comparison)in Tuqiang Forest Bureau in the northern slopes of Great Xing'an Mountains after the catastrophic fire in 1987.Results showed that different planting types had a significant influence on the abundance of larch,Mongolian Scotch pine and white birch.The abundance of larch increased with time,whereas the abundance of Mongolian Scotch pine was in a converse way.The abundance of larch and Mongolian Scotch pine under these planting scenarios was higher than that under natural regeneration.Under these planting scenarios,the abundance of larch increased with the increasing proportion of larch,and the abundance of Mongolian Scotch pine was in a similar way.Contrary to larch and Mongolian Scotch pine,white birch had higher abundance under natural regeneration than that under these planting scenarios.Also,the different proportions of larch and Mongolian Scotch pine had an influence on the abundance of white birch.White birch had higher abundance with the increasing proportion of Mongolian Scotch pine.As for the total abundance of larch and Mongolian Scotch pine,the difference was not significant under P2,P3 and P4 scenarios,but was higher than that under P1 and P5 scenarios,which indicated that individual-species planting should not be used in the forest landscape.

  11. High pressure equation of state for condensed phase thermodynamics

    OpenAIRE

    Nogva, Stig-Erik

    2012-01-01

    In this study a search for an equation of state (EOS) that accurately predicts solids behaviour at both high pressure and temperature has been performed. Firstly, several two-parameter isothermal EOSs for solids under high pressure were investigated. The EOSs evaluated were the Murnaghan, Birch?Murnaghan, Vinet and pseudo-spinodal. The input parameters needed were found through parameter fitting of experimental data. The parameter fitting was done through a second order Murnagh...

  12. Tolerance of an expanding subarctic shrub, Betula glandulosa, to simulated caribou browsing.

    Directory of Open Access Journals (Sweden)

    Emilie Champagne

    Full Text Available Densification of the shrub layer has been reported in many subarctic regions, raising questions about the implication for large herbivores and their resources. Shrubs can tolerate browsing and their level of tolerance could be affected by browsing and soils productivity, eventually modifying resource availability for the caribou. Our objective was to assess the compensatory growth potential of a subarctic shrub, Betula glandulosa Michx., in relation with caribou browsing and nutriment availability for the plants. We used a simulated browsing (0, 25 and 75% of available shoots and nitrogen-fertilisation (0 and 10 g m(-2 experiment to test two main hypotheses linking tolerance to resource availability, the Compensatory Continuum Hypothesis and the Growth Rate Hypothesis as well as the predictions from the Limiting Resource Model. We seek to explicitly integrate the relative browsing pressure in our predictions since the amount of tissues removed could affect the capacity of long-lived plants to compensate. Birches fully compensated for moderate browsing with an overall leaf biomass similar to unbrowsed birches but undercompensated under heavy browsing pressure. The main mechanism explaining compensation appears to be the conversion of short shoots into long shoots. The leaf area increased under heavy browsing pressure but only led to undercompensation. Fertilisation for two consecutive years did not influence the response of birch, thus we conclude that our results support the LRM hypothesis of equal tolerance under both high and low nitrogen availability. Our results highlight that the potential for compensatory growth in dwarf birch is surpassed under heavy browsing pressure independently of the fertilisation regime. In the context of the worldwide decline in caribou herds, the reduction in browsing pressure could act synergistically with global climate change to promote the current shrub expansion reported in subarctic regions.

  13. The Study of the Adhesive Activity and Modification Possibilities of Melamine-Urea-Formaldehyde (MUF), Urea-Formaldehyde (UF) Resins

    OpenAIRE

    Kajaks, J; Kolbins, A

    2014-01-01

    Two types of thermosetting resins MUF and UF have been used as glues for birch wood veneer. As resins modifiers polyvinylacetate emulsion (PVA), polyvinylbutiral (PVB) (powder and solution), rubber latex, adipic (Ad) and sebacic (Seb) acids have been utilized. For glued system shear strength and deformation, bending properties and impact strength have been tested. The best properties: adhesive activity and elasticity have been shown by resins modified with PVB powder, rubber latex, adipic and...

  14. Applying the Australian and New Zealand Risk Management Standard to Information Systems in SMES

    OpenAIRE

    Robyn Davidson; Susan Lambert

    2004-01-01

    This paper advocates the use of the Australia/New Zealand Risk Management Standard (SA/SNZ, 1999) in conjunction with of a modified version of Birch and McEvoy’s (1992) Structured Risk Analysis for Information Systems (SRA-IS) to identify information systems security risks in SMEs. The use of Internet based commerce by SMEs exposes them to information systems security risks that they are ill equipped to recognise let alone mitigate. Unlike the identification of some business risks, identifica...

  15. Woodland: Geographical and Forest Inventory Indications and Criteria (Continuation. Beginning in N. 1, 2014)

    OpenAIRE

    R. A. Ziganshin

    2014-01-01

    The definition of woodland is discussed. The structure and dynamics of forestland are considered on the example of the Tankhoisky forestry district in the South Baikal region. In particular, we consider the representation in the woodland series of forest types, forest inventory compartments by series of forest types, the types of tree species' mixing in the birch forest types. The distribution of all forest types by the productivity classes is done. The age dynamics of tree species' compos...

  16. Eglynų ir beržynų inventorizacijų rezultatų patikimumo analizė

    OpenAIRE

    Memgaudas, Romas

    2006-01-01

    Research report on the reliability of results of Lithuanian forest inventories is given in the thesis. Aim of research – to estimate the reliability of the results of National forest inventory, Stand-wise forest inventory and forest inventory before cutting. Object of research – spruce and birch stands of Lithuanian forests. Methods of research – sampling, verification of statistical hypotheses and comparison of averages. Results of research – the reliability analysis of the results of Nation...

  17. Tree Species Linked to Large Differences in Ecosystem Carbon Distribution in the Boreal Forest of Alaska

    Science.gov (United States)

    Melvin, A. M.; Mack, M. C.; Johnstone, J. F.; Schuur, E. A. G.; Genet, H.; McGuire, A. D.

    2014-12-01

    In the boreal forest of Alaska, increased fire severity associated with climate change is altering plant-soil-microbial feedbacks and ecosystem carbon (C) dynamics. The boreal landscape has historically been dominated by black spruce (Picea mariana), a tree species associated with slow C turnover and large soil organic matter (SOM) accumulation. Historically, low severity fires have led to black spruce regeneration post-fire, thereby maintaining slow C cycling rates and large SOM pools. In recent decades however, an increase in high severity fires has led to greater consumption of the soil organic layer (SOL) during fire and subsequent establishment of deciduous tree species in areas previously dominated by black spruce. This shift to a more deciduous dominated landscape has many implications for ecosystem structure and function, as well as feedbacks to global C cycling. To improve our understanding of how boreal tree species affect C cycling, we quantified above- and belowground C stocks and fluxes in adjacent, mid-successional stands of black spruce and Alaska paper birch (Betula neoalaskana) that established following a 1958 fire near Fairbanks, Alaska. Although total ecosystem C pools (aboveground live tree biomass + dead wood + SOL + top 10 cm of mineral soil) were similar for the two stand types, the distribution of C among pools was markedly different. In black spruce, 78% of measured C was found in soil pools, primarily in the SOL, where spruce contained twice the C stored in paper birch (4.8 ± 0.3 vs. 2.4 ± 0.1 kg C m-2). In contrast, aboveground biomass dominated ecosystem C pools in birch forest (6.0 ± 0.3 vs. 2.5 ± 0.2 kg C m-2 in birch and spruce, respectively). Our findings suggest that tree species exert a strong influence over plant-soil-microbial feedbacks and may have long-term effects on ecosystem C sequestration and storage that feedback to the climate system.

  18. Breeding of the White-Tailed Eagle in the Omsk Region, Russia

    Directory of Open Access Journals (Sweden)

    Boris Yu. Kassal

    2014-11-01

    Full Text Available The White-Tailed Eagle (Haliaeetus albicilla in the Omsk region prefers to breed within the Irtysh River floodplain and its tributaries, as well as along Rahtovo lake and large lake systems (Bolshie Krutinskie, Tyukalinskie, Ilyinskie. Its nests are built mainly on silver birch, aspen, Scots and Siberian pines, white willow and poplars, at a height of 6–15 m with zonal.

  19. Hydrostatic compression of galenobismutite (PbBi2S4)

    DEFF Research Database (Denmark)

    Olsen, Lars Arnskov; Balic Zunic, Tonci; Makovicky, Emil;

    2007-01-01

    Vractometer. The crystal structure was reWned to R1(|F0| > 4s) values of approximately 0.05 at all pressures. By Wtting a third-order Birch-Murnaghan equation of state to the unit-cell volumes V0 = 700.6(2) Å3, K0 = 43.9(7) GPa and dK/dP = 6.9(3) could be determined for the lattice compression. Both types of cations...

  20. Anti-Oxidant and Anti-Inflammatory Activities of Inonotus obliquus and Germinated Brown Rice Extracts

    OpenAIRE

    Beong Ou Lim; Jeong Eun Jo; Da Hye Kim; Trishna Debnath; Sa Ra Park

    2013-01-01

    Inonotus obliquus (IO) is parasitic mushroom that grows on birch and other trees in Russia, Korea, Europe and United States. However, IO is not readily available for consumption due to its high cost and difficult growth. In this regard, IO was inoculated on germinated brown rice (GBR) in the present study and the antioxidant and anti-inflammatory activities of the IO grown on germinated brown rice (IOGBR) extracts were evaluated extensively and compared with those for IO and GBR. IOGBR showed...

  1. Antiviral activity of Inonotus obliquus fungus extract towards infection caused by hepatitis C virus in cell cultures.

    Science.gov (United States)

    Shibnev, V A; Mishin, D V; Garaev, T M; Finogenova, N P; Botikov, A G; Deryabin, P G

    2011-09-01

    Fractions of Inonotus obliquus fungus water extract exhibited a virucidal effect towards hepatitis C virus: it 100-fold reduced its infective properties within 10 min. The antiviral effects of fungus extracts manifested after preventive (24 h before infection) and therapeutic use (during infection of porcine embryo kidney cells). Moreover, the data indicate that the birch fungus extracts inhibit production of infective virus by porcine embryo kidney cells. PMID:22462058

  2. Review of various Techniques in Clustering

    Directory of Open Access Journals (Sweden)

    Megha Gupta

    2013-06-01

    Full Text Available This paper presents the review of various techniques which are used for clustering in data mining.Clustering is the process of dividing data into group of similar objects.Clustering involves various techniques so that the data can be partitioned into groups of same data like k-means algorithm, k-medoid, BIRCH algorithm, chameleon, CLIQUE algorithm, DBSCAN algorithm. In this paper, the overview of these entire algorithms has been discussed.

  3. Uptake and Translocation of Iron by Native Tree Species In A Constructed Wetland Treating Landfill Leachates

    OpenAIRE

    A. Snow; Abdel E. Ghaly; Cote, R.; A. M. Snow

    2008-01-01

    A surface flow wetland was constructed in the Burnside Industrial Park, Dartmouth, Nova Scotia, to treat stormwater runoff from the surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The objectives of this study were: (a) to compare the uptake of iron by red maple, white birch and red spruce trees growing under flooded soil conditions in the constructed wetland and well drained soil conditions in a nearby reference site, (b) to evaluate the...

  4. Extraction of Betulin, Trimyristin, Eugenol and Carnosic Acid Using Water-Organic Solvent Mixtures

    OpenAIRE

    Lugemwa, Fulgentius N.

    2012-01-01

    A solvent system consisting of ethyl acetate, ethyl alcohol and water, in the volume ratio of 4.5:4.5:1, was developed and used to extract, at room temperature, betulin from white birch bark and antioxidants from spices (rosemary, thyme, sage, and oregano) and white oak chips. In addition, under reflux conditions, trimyristin was extracted from nutmeg using the same solvent system, and eugenol from olives was extracted using a mixture of salt water and ethyl acetate. The protocol demonstrates...

  5. Novel treatment strategies and regulation of IgE-mediated allergic disease.

    OpenAIRE

    Thunberg, Sarah

    2008-01-01

    Allergic symptoms such as rhinoconjunctivitis, asthma or gastrointestinal symptoms, triggered by inhaled or ingested allergens cross-linking allergen-specific IgE on mast cells or basophils, are defined as IgE-mediated allergy. The major allergens from birch pollen (Bet v 1) and cat dander (Fel d 1) are two common allergens eliciting allergic disease. Allergen-specific immunotherapy (SIT) is the only curative treatment for IgE-mediated allergy. It is long-lasting and involve...

  6. Climatic information improves statistical individual-tree mortality models for three key species of Sichuan Province, China

    OpenAIRE

    Qiu, Shuai; Xu, Ming; Li, Renqiang; Zheng, Yunpu; Clark, Daniel; Cui, Xiaowei; Liu, Lixiang; Lai, Changhong; Zhang, Wen; Liu, Bo

    2015-01-01

    Key message Climate variables improve individual-tree mortality models for fir, oak and birch.• Context Climate is considered as an important driver of tree mortality, but few studies have included climate factors in models to explore their importance for modelling individual-tree mortality.• Aims To measure the performance of climate-based models, we built individual-tree mortality models using individual, stand, and climate variables for fir (Abies faxoniana Rehd. et Wils.), oak (Quercus aq...

  7. Does tree seedling growth and survival require weeding of Himalayan balsam (Impatiens glandulifera)?

    OpenAIRE

    Ammer, Christian; Schall, Peter; Wördehoff, René; Lamatsch, Klaus; Bachmann, Martin

    2011-01-01

    The effect of Himalayan balsam (Impatiens glandulifera) on survival and growth of naturally regenerated silver birch (Betula pendula) and planted Norway spruce (Picea abies) and silver fir (Abies alba) seedlings was studied in a weeding experiment over 3 years. Three different treatments were applied: control, mowing, and hand weeding by pulling out the entire plant. There were no consistent treatment effects on height and diameter of the tree seedlings. The coverage of Rubus fruticosus had a...

  8. Purification and Characterization of Aeromonas caviae ME-1 Xylanase V, Which Produces Exclusively Xylobiose from Xylan

    OpenAIRE

    Kubata, Bruno Kilunga; Suzuki, Tohru; Horitsu, Hiroyuki; Kawai, Keiichi; Takamizawa, Kazuhiro

    1994-01-01

    A xylanase, which produces exclusively xylobiose from oat spelt and birch xylans, was isolated from the culture medium of Aeromonas caviae ME-1. The enzyme (xylanase V) was purified by ammonium sulfate fractionation, hydrophobic interaction, and ion-exchange and gel filtration chromatographies. The homogeneity of the final preparation was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and agarose gel electrofocusing. The molecular mass and isoelectric point of the x...

  9. Thermokarst rates intensify due to climate change and forest fragmentation in an Alaskan boreal forest lowland.

    Science.gov (United States)

    Lara, Mark J; Genet, Hélène; McGuire, Anthony D; Euskirchen, Eugénie S; Zhang, Yujin; Brown, Dana R N; Jorgenson, Mark T; Romanovsky, Vladimir; Breen, Amy; Bolton, William R

    2016-02-01

    Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of

  10. Universal equation of state for elastic solids; MgSiO3 perovskite is an example

    CERN Document Server

    Garai, Jozsef

    2007-01-01

    Universal (P-V-T) equation of state is derived from theoretical considerations. Correlation coefficients, root-main-square-deviations, and Akaike Information Criterias are used to evaluate the fitting to the experiments of perovskite 0-109 GPa and 293-2000 K. The proposed equation remains valid through the entire pressure and temperature range and has superior fitting parameters in comparison to the Birch-Murnaghan, Vinet, and Roy & Roy equation of states.

  11. The pattern of intrapopulational and interpopulational changes of Betula pendula in Iran, based on leaf morphological traits

    OpenAIRE

    Mohammad Esmaeilpour Poodeh; Kambiz Taheri Abkenar; Ali Aalami; Amireslam Bonyad

    2014-01-01

    Despite superior medicinal properties of Birch, there aren’t any studies reported on its morphological diversity. For the first time, leaf samples were collected from four different sites, each site 10 trees and each tree 30 fertile and sterile shoots and leaves (totally 2400). In analyzing the mean values, the Siahmarz kuh showd the maximum and the Marmishoo minimum size mean. Angle of leaf base and number of veins had minimum and fluctuating asymmetry and distance border had a maximum coeff...

  12. Highlights of forest pest conditions in the maritimes at the end of June, 1993. Technical note No. 285. Annual publication

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, J.E.

    1993-01-01

    This note describes forest pest conditions in the Maritimes at the end of June, 1993. It discusses diseases and pests found including forest tent caterpiller, gypsy moth, red shoots of balsam fir, aspen leafroller, spruce budworm, poplar serpentine leafminer, maple leafroller, and spruce spider mite. Others include elm leafminer, leafroller of birch, satin moth, cherry blight, aspen twoleaf, fall cankerworm, winter moth, and leaf and twig blight of aspen.

  13. Sex for sale: qualitative study of male sex workers

    OpenAIRE

    Wilcox, Aidan; Christmann, Kris

    2006-01-01

    1. RESEARCH AIMS, METHODOLOGY AND LIMITATIONS OF THE RESEARCH The Applied Criminology Centre was approached by the Phil Birch, Principal Community Safety Officer (Specialist Crime Team)/SWEET and Project Manager Community Safety/SWEET Project to investigate the nature and extent of the male sex market in the area. 1.1 RESEARCH AIMS AND OBJECTIVES This study set out to explore the experiences of male sex workers in Kirklees and neighbouring areas. Specifically, it aimed...

  14. Xylan reactions in kraft cooking and their influence on paper sheet properties

    OpenAIRE

    Danielsson, Sverker

    2006-01-01

    Xylan is the main hemicellulose in birch, eucalyptus, and most other hardwood species. During kraft pulping a series of chemical reactions and physical processes involving xylan take place. The processes studied in this thesis are the following: dissolution, degradation, redeposition onto the fibres, side group conversion, and cleavage of side groups off the xylan back bone. The side group in native xylan consists of methylglucuronic acid, which is mainly converted into hexenuronic acid durin...

  15. 以光合效率度量天然白桦种群生态位初探%Primary Probing into Niche of Natural Betula platyphylla Population by Means of Photosynthetic Efficiency

    Institute of Scientific and Technical Information of China (English)

    王爱民; 祖元刚

    2002-01-01

    In terms of photosynthetic efficiency,which demonstrates the space-time function of plant,niche width of B. Platyphylla population was described.First,on the basis of net photosynthetic amount in certain time,the niche width of a birch was calculated.Then,the realized niche and rudimental niche of B. Platyphylla seedlings,young trees and adult trees were discussed.Finally, the dynamic of niche under special conditions was studied.

  16. The effect of different mulches on the growth and yield of organically grown strawberry

    OpenAIRE

    Kivijärvi, P.

    2004-01-01

    Different mulches were studied in field trials over a three-year period under organic production in Mikkeli and Ruukki. The soil type was coarse mineral soil rich in humus. In June 2000, organically produced strawberry plants, cv. Jonsok, were planted in four replicates in double rows, 10 plants/plot, 45 cm apart. The mulching materials were black plastic, flax fibre mat (woodchips+buckwheat husk in 2002), green mass, straw, buckwheat husk, birch woodchips and pine woodchips.

  17. Occupational Rhinoconjunctivitis and Asthma Caused by Chicory and Oral Allergy Syndrome Associated With Bet v 1-Related Protein

    OpenAIRE

    Pirson, F.; Pilette, Charles; Detry, Bruno

    2009-01-01

    We report the case of a patient working in a factory producing inulin from chicory who developed rhinoconjunctivitis and asthma to the dust of dry chicory roots and oral allergy syndrome to raw fruits and vegetables. Nonspecific bronchial hyperresponsiveness was diagnosed. A provocation test with dry chicory induced acute rhinoconjunctivitis and an immediate asthmatic response with no further clinical symptoms. Skin prick test results were positive to birch pollen and fresh/dry chicory, and n...

  18. Structure of active IspH enzyme from escherichia coli provides mechanistic insights into substrate reduction

    KAUST Repository

    Gräwert, Tobias

    2009-07-20

    The terminal step of the non-mevalonate pathway of terpene biosynthesis is catalyzed by IspH (see scheme). In the crystal structure of IspH from E. coli, a bound inorganic diphosphate ligand occupies the position of the diphosphate residue of the substrate. Together with mutation studies and theoretical calculations, these data support a mechanism which is analogous to the Birch reduction of allylic alcohols. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.

  19. Forms of Memory in Post-colonial Australia

    Directory of Open Access Journals (Sweden)

    Lyn McCredden

    2009-06-01

    Full Text Available there are many forms of memory in post-colonial Australia, and many kinds of haunting. This paper investigates the poetry of contemporary Indigenous poets Sam Wagan Watson and Tony Birch, and reads the script of the Federal Government’s February 2008 Apology to the Stolen Generations, asking how and why the nation should be haunted – historically and imaginatively - into the future.

  20. Uses of tree saps in northern and eastern parts of Europe

    Directory of Open Access Journals (Sweden)

    Ingvar Svanberg

    2012-12-01

    Full Text Available In this article we review the use of tree saps in northern and eastern Europe. Published accounts by travellers, ethnologists and ethnobotanists were searched for historical and contemporary details. Field observations made by the authors have also been used. The presented data shows that the use of tree sap has occurred in most north and eastern European countries. It can be assumed that tree saps were most used where there were extensive stands of birch or maple trees, as these two genera generally produce the largest amount of sap. The taxa most commonly used have been Betula pendula, B. pubescens, and Acer platanoides, but scattered data on the use of several other taxa are presented. Tree sap was used as a fresh drink, but also as an ingredient in food and beverages. It was also fermented to make light alcoholic products like ale and wine. Other folk uses of tree saps vary from supplementary nutrition in the form of sugar, minerals and vitamins, to cosmetic applications for skin and hair and folk medicinal use. Russia, Ukraine, Belarus, Estonia, Latvia and Lithuania are the only countries where the gathering and use of sap (mainly birch sap has remained an important activity until recently, due to the existence of large birch forests, low population density and the incorporation of sap into the former Soviet economic system. It is evident that gathering sap from birch and other trees was more widespread in earlier times. There are records indicating extensive use of tree saps from Scandinavia, Poland, Slovakia and Romania, but it is primarily of a historical character. The extraction of tree sap in these countries is nowadays viewed as a curiosity carried out only by a few individuals. However, tree saps have been regaining popularity in urban settings through niche trading.

  1. Soil respiration along an altitudinal gradient in a subalpine secondary forest in China

    OpenAIRE

    Luo S.; Liu G; Li Z; Hu C; Gong L; Wang M; Hu H

    2015-01-01

    The subalpine forest ecosystems in the Miyaluo Forest District in western Sichuan (China) could be very sensitive to global climate change, with important consequences for the regional carbon (C) balance. In a birch secondary forest in this area, we measured plots with (Control) and without (No Litter) leaf litter to explore variation in soil respiration and its relationship with environmental factors along an altitudinal gradient, and to quantify the litter contribution to soil respiration. ...

  2. Development and application of a resin-bag method to determine available nitrogen in forest soils

    OpenAIRE

    Xu, G.; Harrison, A.F.; Grimshaw, H. M.

    1986-01-01

    A resin-bag method was compared to a conventional KC1 extraction procedure for determining available nitrogen in forest soil. Under controlled growth room conditions, both the amounts of ammonium and nitrate nitrogen adsorbed by resin-bags and extracted by 6% KC1 correlated well with the uptake of nitrogen by birch seedlings from 6 widely differing soils. Also, resin-bags placed in situ under 5 differing forest stands and one upland grassland plot gave a close relationship b...

  3. Occupational allergy in Strawberry Greenhouse workers

    OpenAIRE

    Patiwael, Jiska; Vullings, L.G.J.; de Jong, Nicolette; Toorenenbergen, Albert; Gerth Van Wijk, Roy; de Groot, Hans

    2010-01-01

    textabstractBackground: Employees in strawberry greenhouses are highly exposed to several (potential) allergenic agents. However, no occupational allergy in this branch has been described before. First, the presence of work-related allergic symptoms in strawberry workers was explored. Second, we aimed to prove the concept that an IgE-mediated allergy could be responsible for work-related symptoms. To test the possibility of an IgE response secondary to cross-reactivity to birch or grass polle...

  4. Thermokarst Rates Intensify Due to Climate Change and Forest Fragmentation in an Alaskan Boreal Forest Lowland

    Science.gov (United States)

    Lara, M. J.; Genet, H.; McGuire, A. D.; Euskirchen, E. S.; Zhang, Y.; Brown, D. N.; Jorgenson, T.; Romanovsky, V. E.; Breen, A. L.; Bolton, W. R.

    2015-12-01

    Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse scar-bogs, low shrub/scrub, and forests growing on elevated ice rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5o C of thawing. Increases in the collapse of lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998 and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30x30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, respectively. Gradient boosting and regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950-2009 landscape-level analysis estimates a transition of ~15 km² of birch forest area to wetlands on the Tanana Flats, where the greatest change followed warm periods. This work highlights the vulnerability of lowland

  5. Fruit wall anatomical structure of the genus Betula section Lenta (Betulaceae)

    OpenAIRE

    Olga V. Yatsenko; Igor O. Yatsenko

    2014-01-01

    The fruits of the Lentae are referred to lower syncarpous nuts. Unlike most birches, the three-lobed scales in section Lentae stay attached to the axis for a long time. The fruit wall is differentiated into epicarp (derivative of outer tissues of inferior ovary, the tissues of receptacular origin) and the pericarp itself (mesocarp and the endocarp derivating from the ovary wall). The epicarp consists of two zones: epidermis and subepidermal zone. Two-four layers of larger sclerenchymatous cel...

  6. INHIBITION OF THE LIPID OXIDATION PROCESSES BY THE KAZAKHSTANI-SOIL ENDEMIC PLANTS

    Directory of Open Access Journals (Sweden)

    Mashentseva A.A

    2009-12-01

    Full Text Available Phospholipids (PL are universal components of cell membranes. They can be used as objective indices of normal or pathological organism states. The changing nature of the quantitative composition of PL is indicating the intensity of oxidative stress as well as the efficiency of exogenous plant antioxidants.The PL dynamics of the ischemia in experimental rat’s was investigated. The change of that parameter using the preventive injection of some vegetation organs of Kazakhstan birch extract.The extracts of the birch vegetation organs in experimental group were dosed in the amount of 5 mg/kg. In order to investigate PL dynamics, the tissues of brain, liver, and kidney have been studied.In order to estimate the PL change range in rat homogenate, the correlation between neutral and acid PL. Despite the fact that the amount of acid PL in the bio-membranes is less than the neutral ones, the latter regulate membrane functions in a higher degree.It has been found that the rats which had experienced ischemia have a decreased amount of acid PL in the homogenates. Preventive injection of birch extracts brings about normalization of PL level. This fact points out a possibility of applying extracts of Betula Pendula Roth in order to regulate the PL level of experimental rats as well as an estimation of the antioxidant effect of exogenoussubstances.

  7. Exogenous GA3 Application Enhances Xylem Development and Induces the Expression of Secondary Wall Biosynthesis Related Genes in Betula platyphylla

    Directory of Open Access Journals (Sweden)

    Huiyan Guo

    2015-09-01

    Full Text Available Gibberellin (GA is a key signal molecule inducing differentiation of tracheary elements, fibers, and xylogenesis. However the molecular mechanisms underlying the effect of GA on xylem elongation and secondary wall development in tree species remain to be determined. In this study, Betula platyphylla (birch seeds were treated with 300 ppm GA3 and/or 300 ppm paclobutrazol (PAC, seed germination was recorded, and transverse sections of hypocotyls were stained with toluidine blue; the two-month-old seedlings were treated with 50 μM GA3 and/or 50 μM PAC, transverse sections of seedling stems were stained using phloroglucinol–HCl, and secondary wall biosynthesis related genes expression was analyzed by real-time quantitative PCR. Results indicated that germination percentage, energy and time of seeds, hypocotyl height and seedling fresh weight were enhanced by GA3, and reduced by PAC; the xylem development was wider in GA3-treated plants than in the control; the expression of NAC and MYB transcription factors, CESA, PAL, and GA oxidase was up-regulated during GA3 treatment, suggesting their role in GA3-induced xylem development in the birch. Our results suggest that GA3 induces the expression of secondary wall biosynthesis related genes to trigger xylogenesis in the birch plants.

  8. Photosynthetic limitation of several representative subalpine species in the Catalan Pyrenees in summer.

    Science.gov (United States)

    Fernàndez-Martínez, J; Fleck, I

    2016-07-01

    Information on the photosynthetic process and its limitations is essential in order to predict both the capacity of species to adapt to conditions associated with climate change and the likely changes in plant communities. Considering that high-mountain species are especially sensitive, three species representative of subalpine forests of the Central Catalan Pyrenees: mountain pine (Pinus uncinata Mill.), birch (Betula pendula Roth) and rhododendron (Rhododendron ferrugineum L.) were studied under conditions associated with climate change, such as low precipitation, elevated atmospheric [CO2 ] and high solar irradiation incident at Earth's surface, in order to detect any photosynthetic limitations. Short-term high [CO2 ] increased photosynthesis rates (A) and water use efficiency (WUE), especially in birch and mountain pine, whereas stomatal conductance (gs ) was not altered in either species. Birch showed photosynthesis limitation through stomatal closure related to low rainfall, which induced photoinhibition and early foliar senescence. Rhododendron was especially affected by high irradiance, showing early photosynthetic saturation in low light, highest chlorophyll content, lowest gas exchange rates and least photoprotection. Mountain pine had the highest A, photosynthetic capacity (Amax ) and light-saturated rates of net CO2 assimilation (Asat ), which were maintained under reduced precipitation. Furthermore, maximum quantum yield (Fv /Fm ), thermal energy dissipation, PRI and SIPI radiometric index, and ascorbate content indicated improved photoprotection with respect to the other two species. However, maximum velocity of carboxylation of RuBisco (Vcmax ) indicated that N availability would be the main photosynthetic limitation in this species. PMID:26833754

  9. Changes in vegetation since the late glacial on peat bog in the Small Carpathians

    International Nuclear Information System (INIS)

    Mires are ecosystems accumulating high amount of organic matter with preserved micro- and macro-fossils. Thus they can serve as natural archives allowing reconstruction of local vegetation and landscape development. Main aim of this study was to bring evidence of the whole Holocene history of mire birch woodland located on the ridge of the Male Karpaty Mts (SW Slovakia) using pollen analysis. One peat core was sampled from the middle part containing the whole Holocene sequence. The local development of study site started with small lake in a terrain depression, which arose at the end of the Late Glacial (Middle Dryas). The Late Glacial landscape was mosaic of birch-pine forests on suitable places and Artemisia steppes. Early Holocene is characterized by steep decline of pine and increase of Corylus and other mesophilous trees (Quercus, Tilia, Ulmus, Fraxinus). Fagus started dominate in middle Holocene (about 5000 cal BP). The recent vegetation established only several hundred years ago (ca 500 cal. BP), when birch started dominate. (author)

  10. Uptake and Translocation of Manganese by Native Tree Species in a Constructed Wetland Treating Landfill Leachates

    Directory of Open Access Journals (Sweden)

    A. Snow

    2007-01-01

    Full Text Available A surface flow constructed wetland was used to treat stormwater runoff from surrounding watersheds which are comprised primarily of commercial properties and two former landfills. The uptake of manganese by red maple, white birch and red spruce trees growing under flooded soil conditions in the constructed wetland was compared to that of the same trees growing under well drained soil conditions in a nearby reference site. The seasonal variability of manganese and its distribution in different compartments of these trees (leaves, twigs, branches, trunk wood, trunk bark and roots were studied. The average manganese concentrations in the aboveground compartments of red maple, white birch and red spruce trees were within the range of manganese concentrations reported in the literature for these trees. The concentrations of manganese in the aboveground compartments of red maple, white birch and red spruce trees in the reference site were significantly greater than those in the constructed wetland (with the exception of manganese concentrations in the trunk wood of red maple trees because of the acidic soil conditions of the reference site. The percent distribution of manganese in the aboveground compartments of trees did not vary during the growing season. Higher concentrations of manganese were present in the trunk bark and either the leaves or twigs of species on both the constructed wetland and the reference site regardless of the sampling date.

  11. Clustering of foodstuffs in food hypersensitivity. An inquiry study in pollen allergic patients.

    Science.gov (United States)

    Eriksson, N E

    1984-01-01

    600 pollen allergic patients were questioned about hypersensitivity symptoms from various foodstuffs. The answers regarding one foodstuff were compared with those of other foodstuffs making 780 tables, from which the Spearmen 's correlation coefficients were calculated. Most of the combinations of foodstuffs showed statistically significant correlations. The highest value of the correlation coefficient was found for certain combinations: Various nuts reciprocally as well as nuts combined with apple and stone fruits. Stone fruits reciprocally and even stone fruits combined with apple and pear. Apple and pear. Kiwi fruit and avocado. Potato and carrot. Swede , parsnip and celery reciprocally. Strawberry and wild strawberry. Fish and bread, fish and cheese. Beer and wine. Several of the foodstuffs showing high degrees of correlation are known to be associated with birch pollen allergies. It is probable that at least some of these correlations are due to true IgE-mediated cross-reactivity with common allergens in birch pollen and foodstuffs. Other, hitherto less well understood mechanisms, might be at work as well. It is concluded that clustering of foodstuffs is common in food hypersensitivity and that in Sweden this phenomenon mostly is due to the association between birch pollen and some foodstuffs.

  12. The high-pressure behavior of bloedite

    DEFF Research Database (Denmark)

    Comodi, Paola; Nazzareni, Sabrina; Balic Zunic, Tonci;

    2014-01-01

    High-pressure single-crystal synchrotron X‑ray diffraction was carried out on a single crystal of bloedite [Na2Mg(SO4)24H2O] compressed in a diamond-anvil cell. The volume-pressure data, collected up to 11.2 GPa, were fitted by a second- and a third-order Birch-Murnaghan equation of state (EOS......), yielding V0 = 495.6(7) Å3 with K0 = 39.9(6) GPa, and V0 = 496.9(7) Å3, with K0 = 36(1) GPa and K′ = 5.1 (4) GPa-1, respectively. The axial moduli were calculated using a Birch-Murnaghan EOS truncated at the second order, fixing K′ equal to 4, for a and b axes and a third-order Birch-Murnaghan EOS for c...... axis. The results were a0 = 11.08(1) and K0 = 56(3) GPa, b0 = 8.20(2) and K0 = 43(3) GPa, and c0 = 5.528(5), K0 = 40(2) GPa, K′ = 1.7(3) GPa-1. The values of the compressibility for a, b, and c axes are ba = 0.0060(3) GPa-1, bb = 0.0078(5) GPa-1, bc = 0.0083(4) GPa-1 with an anisotropic ratio of ba...

  13. Clustering of foodstuffs in food hypersensitivity. An inquiry study in pollen allergic patients.

    Science.gov (United States)

    Eriksson, N E

    1984-01-01

    600 pollen allergic patients were questioned about hypersensitivity symptoms from various foodstuffs. The answers regarding one foodstuff were compared with those of other foodstuffs making 780 tables, from which the Spearmen 's correlation coefficients were calculated. Most of the combinations of foodstuffs showed statistically significant correlations. The highest value of the correlation coefficient was found for certain combinations: Various nuts reciprocally as well as nuts combined with apple and stone fruits. Stone fruits reciprocally and even stone fruits combined with apple and pear. Apple and pear. Kiwi fruit and avocado. Potato and carrot. Swede , parsnip and celery reciprocally. Strawberry and wild strawberry. Fish and bread, fish and cheese. Beer and wine. Several of the foodstuffs showing high degrees of correlation are known to be associated with birch pollen allergies. It is probable that at least some of these correlations are due to true IgE-mediated cross-reactivity with common allergens in birch pollen and foodstuffs. Other, hitherto less well understood mechanisms, might be at work as well. It is concluded that clustering of foodstuffs is common in food hypersensitivity and that in Sweden this phenomenon mostly is due to the association between birch pollen and some foodstuffs. PMID:6731203

  14. Purification, characterization and N-terminal amino acid sequence of a new major allergen from European chestnut pollen--Cas s 1.

    Science.gov (United States)

    Kos, T; Hoffmann-Sommergruber, K; Ferreira, F; Hirschwehr, R; Ahorn, H; Horak, F; Jager, S; Sperr, W; Kraft, D; Scheiner, O

    1993-11-15

    Pollens from trees of the order Fagales (e.g. birch, alder, hazel, and hornbeam) all contain one major allergen--the main cause for tree pollen allergy. So far the major allergens from birch (Bet v 1), alder (Aln g 1), hazel (Cor a 1), and hornbeam (Car b 1) have been characterized, showing high sequence similarity with each other (1-4). We present the molecular and immunologic characterization of Cas s 1, the major allergen from the European chestnut (Castanea sativa). From aqueous pollen extracts from European chestnut a protein was purified to homogeneity and was subjected to further investigation. The protein revealed a Mr of 22 kDa and was shown to represent the major allergen of the European chestnut (immunoblotting, histamine release) and designated Cas s 1. Despite a marked difference in Mr, Cas s 1 shows significant amino acid sequence similarity at the N-terminus and is antigenically closely related to the major birch pollen allergen Bet v 1 (17 kDa), as shown by binding to the anti-Bet v 1 monoclonal antibody BIP-1 and by IgE-inhibition tests using recombinant Bet v 1.

  15. Thermal Insulation from Hardwood Residues

    Science.gov (United States)

    Sable, I.; Grinfelds, U.; Vikele, L.; Rozenberga, L.; Zeps, M.; Luguza, S.

    2015-11-01

    Adequate heat is one of the prerequisites for human wellbeing; therefore, building insulation is required in places where the outside temperature is not suitable for living. The climate change, with its rising temperatures and longer dry periods, promotes enlargement of the regions with conditions more convenient for hardwood species than for softwood species. Birch (Betula pendula) is the most common hardwood species in Latvia. The aim of this work was to obtain birch fibres from wood residues of plywood production and to form low-density thermal insulation boards. Board formation and production was done in the presence of water; natural binder, fire retardant and fungicide were added in different concentrations. Board properties such as density, transportability or resistance to particulate loss, thermal conductivity and reaction to fire were investigated. This study included thermal insulation boards with the density of 102-120 kg/m3; a strong correlation between density and the binder amount was found. Transportability also improved with the addition of a binder, and 0.1-0.5% of the binder was the most appropriate amount for this purpose. The measured thermal conductivity was in the range of 0.040-0.043 W/(m·K). Fire resistance increased with adding the fire retardant. We concluded that birch fibres are applicable for thermal insulation board production, and it is possible to diversify board properties, changing the amount of different additives.

  16. Phenanthrene Sorption on Biochar-Amended Soils

    DEFF Research Database (Denmark)

    Kumari, K. G I D; Moldrup, Per; Paradelo, Marcos;

    2014-01-01

    Biochar, a byproduct resulting from the pyrolysis of biomass, is considered to be an anthropogenic carbonaceous sorbent. Despite a worldwide increase in the application of biochar on agricultural fields to improve crop productivity over the past few decades, there have been few studies on their i...... carbon, while it negatively correlated with clay content. The results also revealed that biochar-mineral interactions play an important role in the sorption of phenanthrene in biochar-amended soil....... on their influences on the sorption of environmental contaminants. In a field-based study at two experimental sites in Denmark, we investigated the effect of birch wood-derived biochar (Skogans kol) on the sorption of phenanthrene in soils with different properties. The soil sorption coefficient, Kd (L kg-1......), of phenanthrene was measured on sandy loam and loamy sand soils which have received from zero up to 100 t ha-1 of biochar. Results show that birch wood biochar had a higher Kd compared to soils. Furthermore, the application of birch wood biochar enhanced the sorption of phenanthrene in agricultural soils...

  17. Volatile compounds emission from canopy fine litterfall in a hemiboreal mixed forest at Järvselja

    Science.gov (United States)

    Portillo-Estrada, Miguel; Noe, Beate; Noe, Steffen M.

    2013-04-01

    The seasonal distribution of biogenic volatile organic compounds (BVOC) emissions from canopy fine litterfall was investigated over a period of two years. Three stands of a hemiboreal mixed forest were studied. The stands presented different dominant tree species: (1) Norway spruce, (2) Scots pine, and (3) Silver birch and Downy birch. The litterfall was monthly collected in litter traps. The BVOC emission of litter was sampled by placing the litter into a glass jar equipped with a vent tube and pumping the head space air through a VOC adsorbing tube (carbotrap). Adsorbed BVOCs were analyzed in a GC-MS. Fifteen compounds were quantified. Seasonal differences in the total emission of BVOCs were found, defined by a maximum in summer and a minimum in autumn and winter. During summer months, litter emissions were dominated by limonene, α-pinene, camphene and 3-carene in the three litter types, accounting for 70-75 % of total BVOC emitted in June. 3-Carene, α-pinene and β-pinene were the main compounds emitted during winter time, accounting for 50-60 % of total BVOC emitted in January. Stand to stand differences were assessed. The spruce and birch dominated stands showed more similarities in their BVOC emission pattern if compared to the pine dominated stand. Together with the litterfall data, an estimation of the annual total BVOC emitted by the soil litter layer is presented for each stand type.

  18. Accumulation of Triterpenoids in Betula platyphylla Suspension Culture Induced by a Fungal Elicitor%真菌诱导子促进白桦悬浮细胞三萜的积累

    Institute of Scientific and Technical Information of China (English)

    翟俏丽; 范桂枝; 詹亚光

    2011-01-01

    Endophytic fungus of Phomopsis isolated from birch(Betula platyphylla) bark can be used as an elicitor to induce accumulation of triterpenoids in birch cell suspension culture. The change of dry weight and triterpenoids content of birch suspension cell were investigated at early growth phase, exponential growth phase and late growth phase after a fungal elicitor of 40, 100, and 400 (xg-mL"' concentration was added to birch suspension cells. Results showed that different induction schemes all promoted accumulation of triterpenoids, while the treatments reduced the dry weight of birch cells. Suspension cells at exponential growth phase were most easy to be induced, and 40 ng-mL"' fungal elicitor enhanced the triterpenoids content to 29. 47 mg-g"1, increasing by 789$j than that of the control. We investigated changes in pH and conductivity of the medium, and the activity of phenylalanine ammonialyase ( PAL) and peroxidase ( POD) under the optimal induction condition. Results showed that the fungal elicitor induced alkalinization of the medium and increased the conductivity, and significantly increased the activity of PAL and POD of birch suspension cells, which was 5. 70 and S. 74 fold as high as the control after 6 - 10 h of treatment, respectively. These results suggested that fungal elicitation induced defense reaction in birch suspension cell. General phenylpropanoid pathway and oxidative burst might involved in the triterpenoids accumulation induced by the fungal elicitor.%将促进白桦三萜积累的拟茎点霉属的内生真菌诱导子添加到白桦悬浮培养体系中,研究40,100,400pg·mL-1的真菌诱导子对生长初期、指数生长期和生长末期的悬浮细胞干质量和三萜积累的影响.结果表明:真菌诱导子的不同诱导方案均促进白桦悬浮细胞中三萜的积累,而细胞干质量积累却被抑制;其中最佳诱导条件为在指数生长期的白桦细胞中添加40 μg·mL-1的真菌诱导子诱导1天,诱导

  19. Study on the interception of precipitation of coniferous plantations and natural broad-leaved forests in mountain region of northern Yanshan%燕山北部山地人工针叶林及天然阔叶林植被层的降水截留量研究

    Institute of Scientific and Technical Information of China (English)

    纪晓林; 李强; 许中旗; 陈圆圆

    2013-01-01

    In order to compare regulating effects of the artificial coniferous forests and natural broad-leaved forests on precipitation, method of branch soaking was used to compare interception capacity of larch plantations and natural secondary birch forests in the mountain region of northern Yanshan. Results indicated that, in every period, the canopy interception of larch was higher than the natural secondary birch forest. The canopy interception capabilities of larch young forests, middle-age forests, near-mature forests trees were 0. 44 mm, 0. 74 mm and 0. 69 mm, respectively, and those of birch forests were 0. 25 mm, 0. 33 mm, 0. 49 mm, respectively. However, the interception of larch shrubs was lower than natural secondary birch forests. The total interception amount of larch forest vegetation layers was higher than the natural secondary birch forests. As the age prolonged, the trend of birch forest canopy ability increased gradually and young forests, middle-age forests, near-mature forests trees were 0. 41mm, 0. 38mm and 0. 76mm respectively, while the canopy interception ability of larch forests decreased when they were near-matured.%为了比较人工针叶林及天然阔叶林对降水的调控作用,利用泡枝法对燕山北部山地落叶松人工林及天然次生杨桦林植被层对降水的截留量进行了比较.研究结果表明:在各个年龄阶段,落叶松乔木林冠截留量都高于天然次生杨桦林.落叶松人工林幼龄林、中龄林、近熟林乔木林冠截留量分别为0.44 mm、0.74 mm、0.69 mm,杨桦林则分别为0.25 mm、0.33 mm、0.49 mm;但落叶松人工林灌木的截留量低于天然次生杨桦林;华北落叶松人工林植被层总截留量高于天然次生杨桦林,分别是0.48 mm、0.78 mm、0.74 mm.随着林龄的增加,杨桦林林冠截留量有逐渐增加的趋势,幼龄林、中龄林、近熟林分别为0.41 mm、0.38 mm、0.76 mm;但落叶松林到达近熟林时林冠截留量却有所下降.

  20. Changes in species composition and diversity in the restoration process of sub-alpine dark brown coniferous forests in western Sichuan Province, China

    Institute of Scientific and Technical Information of China (English)

    Jiangming MA; Shirong LIU; Zuomin SHI; Yuandong ZHANG; Bing KANG; Baoyu CHEN

    2008-01-01

    By adopting the concept of space as a substi-tute for time, we analyzed the dynamics of species com-position and diversity of different restoration sequences (20, 30, 40, 50 years) in two secondary forest types in western Sichuan Province, distributed in a northerly or northwesterly direction. The analysis was based on the results of measurements of 50 plots located at elevations between 3100-3600 m. The forests originated from nat-ural regeneration in combination with reforestation of spruce when the old-growth bamboo-dark brown con-iferous forests and moss-dark brown coniferous old growth forests were harvested. Similar old-growth dark brown coniferous forests at ages ranging between 160 and 200 years were selected as the reference forests for comparisons. We recorded 167 species of vascular plants from 44 families and 117 genera. There was no significant difference in terms of the number of species among secondary forests. But the importance values of dominant species varied during the restoration pro-cesses. The dominant species in the secondary forests is Betula albo-sinensis, while Abiesfaxoniana is the dom-inant species in old-growth dark brown coniferous for-ests. Species richness increased significantly with restoration processes. It increased quickly in secondary forests during the period from 30 to 40 years, but decreased significantly in the old-growth dark brown coniferous forests. The species richness among growth forms decreased in the following order: herb layer> sh-rub layer > tree layer. The maximum value of the even-ness index occurred in secondary forests at age 40 and remained relatively stable in the bamboo-birch forests, but the evenness index tended to decrease in moss-birch forests and slightly increased in the old-growth moss-dark brown coniferous forests. There was a statistically significant difference in the evenness index between the tree and shrub layers as well as between the tree layer and the herb layer, but there was no

  1. Spatial and Temporal Variation in Feather Moss Associated Nitrogen Fixation in Coniferous and Deciduous Dominated Alaskan Boreal Forests

    Science.gov (United States)

    Jean, M.; Mack, M. C.; Johnstone, J. F.

    2015-12-01

    Dominant canopy tree species have strong effects on the composition and function of understory species. In boreal forests, forest floor bryophytes and their associated microbes are a primary source of ecosystem nitrogen (N) inputs, and thus an important process regulating ecosystem productivity. Bryophyte composition and abundance varies with forest composition, yet how such changes can affect ecosystem processes such as N fixation is still poorly understood. Our goal is to investigate how cyanobacteria-based N fixation occurring in the two most common feather mosses in the Alaskan boreal forest (Pleurozium schreberi and Hylocomium splendens) varies among coniferous and deciduous forest types, over the growing season, and across a nutrient availability gradient. Twelve patches of H. splendens and P. schreberi were identified in three pairs (blocks) of adjacent stands of paper birch (Betula neoalaskana) and black spruce (Picea mariana) near Fairbanks, interior Alaska. Sampling occurred in one block in June, July, August, and September 2014, and in the three blocks once in August 2014. Moss leaf area, moisture and weight, as well as environmental variables such as air temperature and canopy cover were recorded. Fixation rates were consistently higher for P. schreberi than for H. splendens. Overall, N fixation rates were lower in birch than in spruce stands and peaked in August, or July for P. schreberi in birch stands. Moreover, fixation rates varied along the nutrient availability gradient, with fixation rates higher where nutrient availability was lower. This difference was especially clear in spruce stands. Our preliminary results suggest that moss species, canopy type, and environmental factors all influence N fixation rates in Alaskan boreal forests. Our results will enhance the knowledge of the processes that drive N fixation in boreal forests, which is important for predicting ecosystem consequences of changing forest composition.

  2. Identifying Minimum Detectable Change in US Forest Soil Carbon under the Forest Inventory Analysis (FIA) Sampling Strategy

    Science.gov (United States)

    Wu, A. M.; Nater, E. A.; Perry, C. H.; Dalzell, B. J.; Wilson, B.

    2015-12-01

    Estimates of carbon stocks and stock changes in the U.S. Department of Agriculture Forest Service's Forest Inventory and Analysis (FIA) Program are reported as the official United States submission to the UN Framework Convention on Climate Change. Soil, as a critical component of the forest carbon stocks, has been sampled in about 10-year intervals in FIA with the re-measurement underway. However, the magnitude of detectable change in soil organic carbon (SOC) with the current sampling scheme is unknown. We aim to identify SOC variability and to best determine minimum detectable changes in SOC under the current sampling scheme. The project seeks to: identify statistical relationships between SOC and environmental covariates; normalize SOC data for main forest-type groups (FTGs) using identified covariates; and determine the minimum detectable change in the normalized SOC using power analysis. We investigated SOC variability for 8 FTGs: Oak-Hickory, Maple-Beech-Birch, Pinyon-Juniper, Loblolly-Shortleaf Pine, Aspen-Birch, Douglas-Fir, Fir-Spruce-Mountain Hemlock and Woodland Hardwoods. Relationships between SOC and environmental covariates (biomass/soil properties in FIA, PRISM climate data, and DEM-derived terrain attributes) are determined by multiple linear regression and are used to normalize SOC variability. The results showed that terrain attributes were not significant in explaining SOC in the FIA dataset and climate data were only significant in certain FTGs locations. Except for Oak-Hickory, Maple-Beech-Birch and Pinyon-Juniper groups, sample numbers are insufficient to detect a change in SOC less than 10 percent (%) of the mean. To guide future sampling efforts, we will continue our study on detecting minimal change in SOC and to explore sample number and sampling frequency scenarios to inform future soil sampling protocols.

  3. Mineralogical correlation of surficial sediment from area drainages with selected sedimentary interbeds at the Idaho National Engineering Laboratory, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Bartholomay, R.C.

    1990-08-01

    Ongoing research by the US Geological Survey at the INEL involves investigation of the migration of radioactive elements contained in low-level radioactive waste, hydrologic and geologic factors affecting waste movement, and geochemical factors that influence the chemical composition of the waste. Identification of the mineralogy of the Snake River Plain is needed to aid in the study of the hydrology and geochemistry of subsurface waste disposal. The US Geological Surveys project office at the Idaho National Engineering Laboratory, in cooperation with the US Department of Energy, used mineralogical data to correlate surficial sediment samples from the Big Lost River, Little Lost River, and Birch Greek drainages with selected sedimentary interbed core samples taken from test holes at the RWMC (Radioactive Waste Management Complex), TRA (Test Reactors Area), ICPP (Idaho Chemical Processing Plant), and TAN (Test Area North). Correlating the mineralogy of a particular present-day drainage area with a particular sedimentary interbed provides information on historical source of sediment for interbeds in and near the INEL. Mineralogical data indicate that surficial sediment samples from the Big Lost River drainage contained a larger amount of feldspar and pyroxene and a smaller amount of calcite and dolomite than samples from the Little Lost River and Birch Creek drainages. Mineralogical data from sedimentary interbeds at the RWMC, TRA, and ICPP correlate with surficial sediment of the present-day big Lost River drainage. Mineralogical data from a sedimentary interbed at TAN correlate with surficial sediment of the present-day Birch Creek drainage. 13 refs., 5 figs., 3 tabs.

  4. Improvement of the quality of wood derived biofuel-oils; Puuperaeisten biopolttooeljyjen laadun parantaminen. Raakasuovan terminen nestefaasikaesittely hiilivety-polttoaineiksi

    Energy Technology Data Exchange (ETDEWEB)

    Oasmaa, A.; McKeough, P.; Kuoppala, E.; Kylloenen, H.; Levander, J.; Tapola, E.; Haekkinen, R.

    1995-12-31

    Liquid-phase thermochemical processing of tall oil soap has been experimentally investigated. The organic matter of tall oil soap, which is a by-product of kraft pulping, originates mainly from wood extractives. Conventional processing of tall oil soap involves acidulation to yield crude tall oil and subsequent distillation of the oil at centralized refineries. Because tall oil originating from birch wood is far less valuable than that from pine, there is an economic incentive in the Nordic countries to develop alternative conversion processes for the tall oil soap produced at pulp mills where birch is widely used as feedstock. Both catalytic hydrotreatment and liquid-phase thermal treatment of a mixed pine/birch soap have been investigated in the laboratory. Liquid and gaseous hydrocarbons were the principal products formed in both types of treatment. Although the liquid product formed under hydrotreatment conditions contained a higher proportion of aliphatic compounds, it was clear that the thermal treatment process would be, economically, the more favorable option. In the thermal process, a predominantly hydrocarbon oil product was obtained at 450 deg C using a residence time of at least 60 min. About 50 % of the energy content of the tall oil soap was recovered as oil product, about 30 % as gases, and about 20 % as organic material contained in an aqueous slurry phase. When the oil product was carefully separated from the aqueous slurry phase, only trace amounts of impurities, such as water, sodium and organic acid salts were present in the product. A techno-economic evaluation of the process concept has been performed. The economics of the thermal treatment process appear to be favorable in comparison with those of the conventional acidulation process

  5. The potential of Dark Septate Endophytes to form root symbioses with ectomycorrhizal and ericoid mycorrhizal middle European forest plants.

    Science.gov (United States)

    Lukešová, Tereza; Kohout, Petr; Větrovský, Tomáš; Vohník, Martin

    2015-01-01

    The unresolved ecophysiological significance of Dark Septate Endophytes (DSE) may be in part due to existence of morphologically indistinguishable cryptic species in the most common Phialocephala fortinii s. l.--Acephala applanata species complex (PAC). We inoculated three middle European forest plants (European blueberry, Norway spruce and silver birch) with 16 strains of eight PAC cryptic species and other DSE and ectomycorrhizal/ericoid mycorrhizal fungi and focused on intraradical structures possibly representing interfaces for plant-fungus nutrient transfer and on host growth response. The PAC species Acephala applanata simultaneously formed structures resembling ericoid mycorrhiza (ErM) and DSE microsclerotia in blueberry. A. macrosclerotiorum, a close relative to PAC, formed ectomycorrhizae with spruce but not with birch, and structures resembling ErM in blueberry. Phialocephala glacialis, another close relative to PAC, formed structures resembling ErM in blueberry. In blueberry, six PAC strains significantly decreased dry shoot biomass compared to ErM control. In birch, one A. macrosclerotiorum strain increased root biomass and the other shoot biomass in comparison with non-inoculated control. The dual mycorrhizal ability of A. macrosclerotiorum suggested that it may form mycorrhizal links between Ericaceae and Pinaceae. However, we were unable to detect this species in Ericaceae roots growing in a forest with presence of A. macrosclerotiorum ectomycorrhizae. Nevertheless, the diversity of Ericaceae mycobionts was high (380 OTUs) with individual sites often dominated by hitherto unreported helotialean and chaetothyrialean/verrucarialean species; in contrast, typical ErM fungi were either absent or low in abundance. Some DSE apparently have a potential to form mycorrhizae with typical middle European forest plants. However, except A. applanata, the tested representatives of all hitherto described PAC cryptic species formed typical DSE colonization without

  6. Current state of forest mapping with Landsat data in Siberia

    Science.gov (United States)

    Maksyutov, Shamil; Sedykh, Vladimir; Kuzmenko, Ekaterina; Farber, Sergey; Kalinicheva, Svetlana; Fedorov, Alexander; Schepaschenko, Dmitry

    2016-04-01

    We review a current state of a forest type mapping with Landsat data in Siberia. Target algorithm should be based on dynamic vegetation approach to be applicable to the analysis of the forest type distribution for Siberia, aiming at capability of mapping Siberian forest landscapes for applications such as predicting response of forest composition to climate change. We present data for several areas in West Siberian middle taiga, Central Siberia and East Siberia near Yakutsk. Analysis of the field survey, forest inventory data was made to produce forest type classification accounting for several stages for forest succession and variations in habitats and landforms. Supervised classification was applied to the areas were the ground truth and inventory data are available, including several limited area maps and vegetation survey transects. In Laryegan basin in West Siberia the upland forest areas are dominated by mix of Scots pine on sandy soils and Siberian pine with presence of fir and spruce on the others. Abundance of Scots pine decreases to the west due to change in soils. Those types are separable using Landsat spectral data. In the permafrost area around Yakutsk the most widespread succession type is birch to larch. Three stages of the birch to larch succession are detectable from Landsat image. When Landsat data is used in both West and East Siberia, distinction between deciduous broad-leaved species (birch, aspen, and willow) is generally difficult. Similar problem exist for distinguishing between dark coniferous species (Siberian pine, fir and spruce). Image classification can be improved by applying landform type analysis, such as separation into floodplain, terrace, sloping hills. Additional layers of information can be a promising way to complement Landsat data.

  7. A significant carbon sink in temperate forests in Beijing: based on 20-year field measurements in three stands.

    Science.gov (United States)

    Zhu, JianXiao; Hu, XueYang; Yao, Hui; Liu, GuoHua; Ji, ChenJun; Fang, JingYun

    2015-11-01

    Numerous efforts have been made to characterize forest carbon (C) cycles and stocks in various ecosystems. However, long-term observation on each component of the forest C cycle is still lacking. We measured C stocks and fluxes in three permanent temperate forest plots (birch, oak and pine forest) during 2011–2014, and calculated the changes of the components of the C cycle related to the measurements during 1992–1994 at Mt. Dongling, Beijing, China. Forest net primary production in birch, oak, and pine plots was 5.32, 4.53, and 6.73 Mg C ha-1 a-1, respectively. Corresponding net ecosystem production was 0.12, 0.43, and 3.53 Mg C ha-1 a-1. The C stocks and fluxes in 2011–2014 were significantly larger than those in 1992–1994 in which the biomass C densities in birch, oak, and pine plots increased from 50.0, 37.7, and 54.0 Mg C ha-1 in 1994 to 101.5, 77.3, and 110.9 Mg C ha-1 in 2014; soil organic C densities increased from 207.0, 239.1, and 231.7 Mg C ha-1 to 214.8, 241.7, and 238.4 Mg C ha-1; and soil heterotrophic respiration increased from 2.78, 3.49, and 1.81 Mg C ha-1 a-1 to 5.20, 4.10, and 3.20 Mg C ha-1 a-1. These results suggest that the mountainous temperate forest ecosystems in Beijing have served as a carbon sink in the last two decades. These observations of C stocks and fluxes provided field-based data for a long-term study of C cycling in temperate forest ecosystems. PMID:26501378

  8. The Influence of Dipping Technology on Fire Retardant Retention Quantity of FRW Fire-Retarding Veneer%浸渍工艺对FRW阻燃单板载药量的影响

    Institute of Scientific and Technical Information of China (English)

    刘迎涛; 乔磊; 李晓乐; 林会峰; 姜道鸿; 韩爽

    2012-01-01

    The new-type fire retardant FRW was selected to treat poplar and birch veneer, and the influence of the treatment technology conditions including the soaking time and solution concentration, veneer thickness and the timber of different tree species on the fire retardant retention quantity of the FRW fire-retarding veneer was studied. The results showed that along with the prolonging of soaking time duration and increasing of the solution concentration, the fire retardant retention quantity of the poplar and birch veneer both increased. There was difference in the fire retardant retention quantity between the tree species, the fire retardant retention quantity of poplar veneer was higher than that of the birch veneer. At the same time, with the increase of veneer thickness, the fire retardant retention quantity showed a downward trend in the overall.%选用新型木材阻燃剂FRW处理杨木和桦木单板,探讨浸渍工艺条件(浸渍时间和浸渍浓度)、单板厚度、树种等因素对FRW阻燃单板载药量的影响.结果表明:随着单板浸渍时间的增加和浸渍浓度的提高,杨木和桦木的单板载药量均呈上升趋势;树种不同,其载药量存在差异,杨木单板的载药量高于桦木单板;随着单板厚度的增加,单板载药量在整体上呈下降趋势.

  9. Outbreaks by canopy-feeding geometrid moth cause state-dependent shifts in understorey plant communities.

    Science.gov (United States)

    Karlsen, Stein Rune; Jepsen, Jane Uhd; Odland, Arvid; Ims, Rolf Anker; Elvebakk, Arve

    2013-11-01

    The increased spread of insect outbreaks is among the most severe impacts of climate warming predicted for northern boreal forest ecosystems. Compound disturbances by insect herbivores can cause sharp transitions between vegetation states with implications for ecosystem productivity and climate feedbacks. By analysing vegetation plots prior to and immediately after a severe and widespread outbreak by geometrid moths in the birch forest-tundra ecotone, we document a shift in forest understorey community composition in response to the moth outbreak. Prior to the moth outbreak, the plots divided into two oligotrophic and one eutrophic plant community. The moth outbreak caused a vegetation state shift in the two oligotrophic communities, but only minor changes in the eutrophic community. In the spatially most widespread communities, oligotrophic dwarf shrub birch forest, dominance by the allelopathic dwarf shrub Empetrum nigrum ssp. hermaphroditum, was effectively broken and replaced by a community dominated by the graminoid Avenella flexuosa, in a manner qualitatively similar to the effect of wild fires in E. nigrum communities in coniferous boreal forest further south. As dominance by E. nigrum is associated with retrogressive succession the observed vegetation state shift has widespread implications for ecosystem productivity on a regional scale. Our findings reveal that the impact of moth outbreaks on the northern boreal birch forest system is highly initial-state dependent, and that the widespread oligotrophic communities have a low resistance to such disturbances. This provides a case for the notion that climate impacts on arctic and northern boreal vegetation may take place most abruptly when conveyed by changed dynamics of irruptive herbivores. PMID:23568711

  10. A significant carbon sink in temperate forests in Beijing: based on 20-year field measurements in three stands

    Science.gov (United States)

    Zhu, J.

    2015-12-01

    Numerous efforts have been made to characterize the forest carbon (C) cycles and stocks. However, long-term observation-based quantification on each component of the forest C cycle and its change is still lacking. We measured C stocks and fluxes in three permanent temperate forest plots (birch, oak and pine forest plots) during 2011-2014 and calculated the changes of the C cycle components related to the measurements during 1992-1994 in Mt. Dongling, Beijing, China. Our results showed that forest net primary production in birch, oak and pine plots were 5.32, 4.53 and 6.73 Mg C ha-1 yr-1, respectively. The corresponding net ecosystem production were 0.12, 0.43 and 3.53 Mg C ha-1 yr-1. The C stocks and fluxes in 2011-2014 were significantly larger than those in 1992-1994: the biomass C densities in birch, oak and pine plots increased from 50.0, 37.7 and 54.0 Mg C ha-1 in 1994 to 101.5, 77.3 and 110.9 Mg C ha-1 in 2014; soil organic C densities from 207.0, 239.1 and 231.7 Mg C ha-1 to 214.8, 241.7 and 238.4 Mg C ha-1; and soil heterotrophic respiration from 2.78, 3.49 and 1.81 Mg C ha-1 yr-1 to 5.20, 4.10 and 3.20 Mg C ha-1 yr-1. These results suggest that the mountainous temperate forest ecosystems are a carbon sink in the recent two decades. These observations of C densities and fluxes provided field-based data for long-term study of C cycling in temperate forest ecosystems.

  11. The potential of Dark Septate Endophytes to form root symbioses with ectomycorrhizal and ericoid mycorrhizal middle European forest plants.

    Directory of Open Access Journals (Sweden)

    Tereza Lukešová

    Full Text Available The unresolved ecophysiological significance of Dark Septate Endophytes (DSE may be in part due to existence of morphologically indistinguishable cryptic species in the most common Phialocephala fortinii s. l.--Acephala applanata species complex (PAC. We inoculated three middle European forest plants (European blueberry, Norway spruce and silver birch with 16 strains of eight PAC cryptic species and other DSE and ectomycorrhizal/ericoid mycorrhizal fungi and focused on intraradical structures possibly representing interfaces for plant-fungus nutrient transfer and on host growth response. The PAC species Acephala applanata simultaneously formed structures resembling ericoid mycorrhiza (ErM and DSE microsclerotia in blueberry. A. macrosclerotiorum, a close relative to PAC, formed ectomycorrhizae with spruce but not with birch, and structures resembling ErM in blueberry. Phialocephala glacialis, another close relative to PAC, formed structures resembling ErM in blueberry. In blueberry, six PAC strains significantly decreased dry shoot biomass compared to ErM control. In birch, one A. macrosclerotiorum strain increased root biomass and the other shoot biomass in comparison with non-inoculated control. The dual mycorrhizal ability of A. macrosclerotiorum suggested that it may form mycorrhizal links between Ericaceae and Pinaceae. However, we were unable to detect this species in Ericaceae roots growing in a forest with presence of A. macrosclerotiorum ectomycorrhizae. Nevertheless, the diversity of Ericaceae mycobionts was high (380 OTUs with individual sites often dominated by hitherto unreported helotialean and chaetothyrialean/verrucarialean species; in contrast, typical ErM fungi were either absent or low in abundance. Some DSE apparently have a potential to form mycorrhizae with typical middle European forest plants. However, except A. applanata, the tested representatives of all hitherto described PAC cryptic species formed typical DSE

  12. Umatilla River Subbasin Fish Habitat Improvement Program, 1996-2003 Summary Report.

    Energy Technology Data Exchange (ETDEWEB)

    St. Hilaire, Danny R.; Montgomery, Michael; Bailey, Timothy D. (Oregon Department of Fish and Wildlife, John Day, OR)

    2005-01-01

    This annual report is in fulfillment of contractual obligations with Bonneville Power Administration (BPA), which is the funding source for the Oregon Department of Fish and Wildlife's (ODFW), Umatilla River Subbasin Fish Habitat Improvement Program (Program). The last Annual Program Report was submitted in 1997, and described projects undertaken in 1995. This report describes Program activities carried out in 2003, along with a summary of projects undertaken during the years 1996 through 2002. The Program works cooperatively with private landowners to develop long-term restoration agreements, under which, passive and active Habitat Improvement Projects are conducted. Historically, projects have included livestock exclusion fencing (passive restoration) to protect riparian habitats, along with the installation of instream structures (active restoration) to address erosion and improve fish habitat. In recent years, the focus of active restoration has shifted to bioengineering treatments and, more recently, to channel re-design and re-construction aimed at improving fish habitat, by restoring stable channel function. This report provides a summary table of past projects (1996-2002), along with a text description of more extensive habitat improvement projects, including: (1) Implementation of a four-phased project on the Lobato property (Birch Creek) beginning in 1996 and involving a demonstration bioengineering site and riparian improvements (fencing, planting), (2) Implementation of stable channel design/instream structure placement on the Houser property, East Birch Creek, beginning in 1998, an (3) Implementation of a joint, US Army Corps of Engineers/ODFW (cost share) project beginning in 2001 on the Brogoitti property, East Birch Creek, which involved implementation of stable channel design/construction and riparian improvement treatments.

  13. Buried late holocene paleosols of the nienshants cultural-historical monument in St. Petersburg

    Science.gov (United States)

    Rusakov, A. V.; Nikonov, A. A.; Savelieva, L. A.; Pinakhina, D. V.

    2013-01-01

    Buried Late Holocene paleosols of the Nienshants historical monument at the junction of the Neva and Okhta rivers (St. Petersburg) have been studied. These soils developed from estuary deposits of the Littorina basin with abundant artifacts of the Neolithic and Early Iron ages (7-2 ka BP). The soil cover of the area consists of the mature dark-humus profile-gleyed soils on elevated elements of the mesotopography (3.0-3.5 a.s.l.) and dark-humus gley soils in the local depressions (2.0-2.6 m a.s.l.). The soils are characterized by the low to moderate content of humus of the fulvate-humate type. The beginning of humus formation in the dark-humus gley soil on the slope facing the Neva River is estimated at about 2600 yrs ago; for the darkhumus profile-gleyed soils of the studied paleocatena, at about 2000 and 1780 yrs ago; and for the darkhumus gley soil, at about 1440 years ago. Judging from the spore-pollen spectra, the development of these soils took place in the Subatlantic period under birch and pine-birch forests with the admixture of spruce and alder trees. The gleyed horizons of the buried soil at the depth of 1.6-1.2 m on the Neva-facing slope date back to the Late Subboreal period (2500-2600 yrs ago), when pine-birch-spruce forests were widespread in the area. The new data contribute to our knowledge of the environmental conditions during the Neolithic and Iron ages.

  14. [Effects of soil temperature and moisture on soil respiration in different forest types in Changbai Mountain].

    Science.gov (United States)

    Wang, Miao; Ji, Lanzhu; Li, Qiurong; Liu, Yanqiu

    2003-08-01

    The effects of soil temperature (0, 5, 15, 25, 35 degrees C) and water content on soil respiration in three forest types in Changbai Mountain were evaluated in laboratory condition. The results indicated that the soil respiration rate was positively correlated to soil temperature from 0 to 35 degrees C and it increased with soil water content from 0.21 to 0.37 kg.kg-1. The soil respiration rate decreased with soil water content when water content was over the range. The result suggested the interactive effects of temperature and water content on soil respiration. There were significant differences in soil respiration among the various forest types and the highest was in broad leaf Korean pine forest, then in erman's birch forest, and it was the lowest in dark coniferous forest. The optimal condition for soil respiration in broad-leaved Korean pine forest was at 35 degrees C under 0.37 kg.kg-1 water content, and it was at 25 degrees C under 0.21 kg.kg-1 in dark coniferous forest and at 35 degrees C under 0.37 kg.kg-1 water content in erman's birch forest. Because the forests of broad leaf Korean pine, dark coniferous and erman's birch are located at various altitudes, the soil temperatures had 4-5 degrees C variation in different forest types during the same period. The soil respiration rates measured in brown pine mountain soil were lower than those in dark brown forest and they were higher in mountain grass forest soil than those in brown pine mountain soil. PMID:14655349

  15. Comparison of the protection effectiveness of acrylic polyurethane coatings containing bark extracts on three heat-treated North American wood species: Surface degradation

    Science.gov (United States)

    Kocaefe, Duygu; Saha, Sudeshna

    2012-04-01

    High temperature heat-treatment of wood is a very valuable technique which improves many properties (biological durability, dimensional stability, thermal insulating characteristics) of natural wood. Also, it changes the natural color of wood to a very attractive dark brown color. Unfortunately, this color is not stable if left unprotected in external environment and turns to gray or white depending on the wood species. To overcome this problem, acrylic polyurethane coatings are applied on heat-treated wood to delay surface degradations (color change, loss of gloss, and chemical modifications) during aging. The acrylic polyurethane coatings which have high resistance against aging are further modified by adding bark extracts and/or lignin stabilizer to enhance their effectiveness in preventing the wood aging behavior. The aging characteristic of this coating is compared with acrylic polyurethane combined with commercially available organic UV stabilizers. In this study, their performance on three heat-treated North American wood species (jack pine, quaking aspen and white birch) are compared under accelerated aging conditions. Both the color change data and visual assessment indicate improvement in protective characteristic of acrylic polyurethane when bark extracts and lignin stabilizer are used in place of commercially available UV stabilizer. The results showed that although acrylic polyurethane with bark extracts and lignin stabilizer was more efficient compared to acrylic polyurethane with organic UV stabilizers in protecting heat-treated jack pine, it failed to protect heat-treated aspen and birch effectively after 672 h of accelerated aging. This degradation was not due to the coating adhesion loss or coating degradation during accelerated aging; rather, it was due to the significant degradation of heat-treated aspen and birch surface beneath this coating. The XPS results revealed formation of carbonyl photoproducts after aging on the coated surfaces and

  16. Effect of Heat Treatment on Sorption Properties and Dimensional Stability of Wood

    Directory of Open Access Journals (Sweden)

    Povilas NAVICKAS

    2013-09-01

    Full Text Available This research was performed in order to determine how the heating process affects sorption properties and dimensional and shape stability of oak, lime and birch wood. By subjecting specimens to 3 hours heating at 130, 160, 190 and 220 ºC temperatures, a decrease in volume, density and mass was observed in proportion to the applied temperature. It was established that when oak wood specimens underwent heating at 220 ºC temperature, the decline of mass was 1.2 times higher than in the case of birch specimens. Both heated and unheated specimens underwent moistening in air at 25 ºC ±1 ºC temperature for 3 weeks with relative humidity being 85 % ±1 % and were soaked in water at room temperature for 4 hours. It was found that after applying high temperature heating, specimens absorbed smaller amounts of moisture. It was demonstrated that during the soaking process, the volume of unheated specimens was 3 times higher than in the case of specimens heated at 220 ºC temperature. The change in the volume of unheated oak was 1.27 times smaller than in the case of lime specimens and 1.16 times larger than in the case of birch specimens, which underwent heating at 220 ºC temperature. In addition, specimens that were exposed to heat had more stable measurements and shapes. It was noticed that the heating process caused significant changes in moisture and dimensional stability of specimens, when higher temperatures ranging from 190 ºC to 220 ºC were used. DOI: http://dx.doi.org/10.5755/j01.ms.19.3.5239

  17. Mineralogical correlation of surficial sediment from area drainages with selected sedimentary interbeds at the Idaho National Engineering Laboratory, Idaho

    International Nuclear Information System (INIS)

    Ongoing research by the US Geological Survey at the INEL involves investigation of the migration of radioactive elements contained in low-level radioactive waste, hydrologic and geologic factors affecting waste movement, and geochemical factors that influence the chemical composition of the waste. Identification of the mineralogy of the Snake River Plain is needed to aid in the study of the hydrology and geochemistry of subsurface waste disposal. The US Geological Surveys project office at the Idaho National Engineering Laboratory, in cooperation with the US Department of Energy, used mineralogical data to correlate surficial sediment samples from the Big Lost River, Little Lost River, and Birch Greek drainages with selected sedimentary interbed core samples taken from test holes at the RWMC (Radioactive Waste Management Complex), TRA (Test Reactors Area), ICPP (Idaho Chemical Processing Plant), and TAN (Test Area North). Correlating the mineralogy of a particular present-day drainage area with a particular sedimentary interbed provides information on historical source of sediment for interbeds in and near the INEL. Mineralogical data indicate that surficial sediment samples from the Big Lost River drainage contained a larger amount of feldspar and pyroxene and a smaller amount of calcite and dolomite than samples from the Little Lost River and Birch Creek drainages. Mineralogical data from sedimentary interbeds at the RWMC, TRA, and ICPP correlate with surficial sediment of the present-day big Lost River drainage. Mineralogical data from a sedimentary interbed at TAN correlate with surficial sediment of the present-day Birch Creek drainage. 13 refs., 5 figs., 3 tabs

  18. Bayesian analysis of the species-specific lengthening of the growing season in two European countries and the influence of an insect pest

    Science.gov (United States)

    Menzel, Annette; Estrella, Nicole; Heitland, Werner; Susnik, Andreja; Schleip, Christoph; Dose, Volker

    2008-01-01

    A recent lengthening of the growing season in mid and higher latitudes of the northern hemisphere is reported as a clear indicator for climate change impacts. Using data from Germany (1951-2003) and Slovenia (1961-2004), we study whether changes in the start, end, and length of the growing season differ among four deciduous broad-leaved tree species and countries, how the changes are related to temperature changes, and what might be the confounding effects of an insect attack. The functional behaviour of the phenological and climatological time series and their trends are not analysed by linear regression, but by a new Bayesian approach taking into account different models for the functional description (one change-point, linear, constant models). We find advanced leaf unfolding in both countries with the same species order (oak > horse chestnut, beech, and birch). However, this advance is non linear over time and more apparent in Germany with clear change-points in the late 1970s, followed by marked advances (on average 3.67 days decade-1 in the 2000s). In Slovenia, we find a more gradual advance of onset dates (on average 0.8 days decade-1 in the 2000s). Leaf colouring of birch, beech, and oak has been slightly delayed in the last 3 decades, especially in Germany, however with no clear functional behaviour. Abrupt changes in leaf colouring dates of horse chestnut with recent advancing onset dates can be linked across countries to damage by a newly emerging pest, the horse chestnut leaf-miner ( Cameraria ohridella). The lengthening of the growing season, more distinct in Germany than in Slovenia (on average 4.2 and 1.0 days decade-1 in the 2000s, respectively), exhibits the same species order in both countries (oak > birch > beech). Damage by horse chestnut leaf-miner leads to reduced lengthening (Germany) and drastic shortening (Slovenia) of the horse chestnut growing season (-12 days decade-1 in the 2000s). Advanced spring leaf unfolding and lengthening of the

  19. FLUCTUATING ASYMMETRY OF BETULA PENDULA LEAVES AS A BIOINDICATOR OF AEROTECHNOGENIC POLLUTION OF AGROLANDSCAPES

    OpenAIRE

    Lobkov, V.; Vetrova, J.

    2014-01-01

    The main goal of our research was to determine the variability model and fluctuating asymmetry indices of the metric signs of Betula pendula as a typical species which grow uniformly in the Orel region and Orel.The following problems were solved:to collect material in the planting of silver birch in two areas;to determine the parameters of Betula pendula leaf blade and the level of its asymmetry; to explore the basic statistical properties of the asymmetry parameters of the individual feature...

  20. Analysis of trees planted in vicinity of hospitals in Ljubljana as a source of pollen

    OpenAIRE

    Kofol Seliger, Andreja; Pirnat, Janez

    2010-01-01

    The paper analyses woody plants growing in the vicinity of hospital buildings situated along Zalog Road, Korytko Street, Šlajmar Street, Bohorič Street and Njegoš Street in Ljubljana, Slovenia. Woody plants are an immediate potential source of allergenic pollen, affecting all park users such as patients, visitors and hospital employees. The most allergenic tree species in the park was found to be birch (Betula pendula Roth.), which accounts for 6.8% of all registered trees. The low allergenic...

  1. THE EFFECT OF HARDWOOD FIBER MORPHOLOGY ON THE HYGROEXPANSIVITY OF PAPER

    Directory of Open Access Journals (Sweden)

    Iiro Pulkkinen

    2009-02-01

    Full Text Available The purpose of this investigation was to study the effect of fiber characteristics, especially fiber wall thickness, on the hygroexpansion behavior of paper due to humidity changes. Five different eucalyptus Kraft pulp samples were studied with an OPTIDIM hygroexpansivity tester. As a reference, birch and acacia were included. In all, seven pulp samples were refined at low consistency (LC, using a Voith Sulzer refiner. Both anisotropic and isotropic sheets were investigated. The sheets were dried under restraint. The results showed that fiber wall thickness is an important factor in controlling the hygroexpansivity of paper through fiber network activation.

  2. Effect of the synthesis temperature of porous carbon-metal oxide composites on the gold particle morphology

    Science.gov (United States)

    Tsyganova, S. I.; Zhizhaev, A. M.; Mikhlin, Yu. L.; Patrushev, V. V.; Bondarenko, G. N.; Korol'kova, I. V.

    2014-10-01

    The state of gold deposited from a chloride solution on the surface of the porous magnetite-carbon composite obtained from modified birch saw dust at 400 and 800°C was studied by electron microscopy, X-ray photoelectron spectroscopy, and XRD analysis. The shape and size of the deposited gold crystallites depend on the synthesis temperature of the composite. The deposited gold crystallites were mainly ray-shaped at the synthesis temperature of 400°C and spheroid at 800°C.

  3. Sequential parametric optimization of methane production from different sources of forest raw material

    Directory of Open Access Journals (Sweden)

    Leonidas eMatsakas

    2015-10-01

    Full Text Available The increase in environmental problems and the shortage of fossil fuels have led to the need for action in the development of sustainable and renewable fuels. Methane is produced through anaerobic digestion of organic materials and is a biofuel with very promising characteristics. The success in using methane as a biofuel has resulted in the operation of several commercial-scale plants and the need to exploit novel materials to be used. Forest biomass can serve as an excellent candidate for use as raw material for anaerobic digestion. During this work, both hardwood and softwood species―which are representative of the forests of Sweden―were used for the production of methane. Initially, when untreated forest materials were used for the anaerobic digestion, the yields obtained were very low, even with the addition of enzymes, reaching a maximum of only 40 mL CH4/g VS when birch was used. When hydrothermal pretreatment was applied, the enzymatic digestibility improved up to 6.7 times relative to that without pretreatment, and the yield of methane reached up to 254 mL CH4/g VS. Then the effect of chemical/enzymatic detoxification was examined, where laccase treatment improved the methane yield from the more harshly pretreated materials while it had no effect on the more mildly pretreated material. Finally, addition of cellulolytic enzymes during the digestion improved the methane yields from spruce and pine, whereas for birch separate saccharification was more beneficial. To achieve high yields in spruce 30 FPU/g was necessary, whereas 15 FPU/g was enough when pine and birch were used. During this work, the highest methane yields obtained from pine and birch were 179.9 mL CH4/g VS and 304.8 mL CH4/g VS, respectively. For mildly and severely pretreated spruce, the methane yields reached 259.4 mL CH4/g VS and 276.3 mL CH4/g VS, respectively. We have shown that forest material can serve as raw material for efficient production of methane. The

  4. Human Leukocyte Antigen-G and Regulatory T Cells during Specific Immunotherapy for Pollen Allergy

    DEFF Research Database (Denmark)

    Sørensen, Anja Elaine; Johnsen, Claus R; Dalgaard, Louise Torp;

    2013-01-01

    of the cytokine profile towards a TH1-polarized immune response. We investigated the effects of SIT on T cells, on immunomodulation of human leukocyte antigen (HLA)-G, which has been associated with allergy, on regulatory cytokine expression, and on serum allergen-specific antibody subclasses (IgE and IgG4......). Methods: Eleven birch and/or grass pollen-allergic patients and 10 healthy nonatopic controls were studied before and during SIT. Tregs, chemokine receptors, soluble HLA-G (sHLA-G), Ig-like transcript (ILT) 2, specific IgE, and IgG4 were studied. Peripheral blood mononuclear cells (PBMCs) were stimulated...

  5. Compressibility of Nickel Nanoparticle Chain

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-Dong; TANG Ling-Yun; LI Yan-Chun; LIU Jing

    2007-01-01

    We perform the high-pressure energy dispersive x-ray diffraction experiments of nickel nanoparticle chain using a synchrotron source under quasi-hydrostatic compression up to 44.7GPa. There is no phase transition over the pressure range. The bulk modulus Kg, the first pressure derivative of bulk modulus K'0 and the volume Vo are calculated from the pressure-volume data using the Birch-Murnaghan equation of state. A decrease of compressibility is observed, in agreement with the Hall-Petch effect.

  6. Direct contact between dendritic cells and bronchial epithelial cells inhibits T cell recall responses towards mite and pollen allergen extracts in vitro

    DEFF Research Database (Denmark)

    Papazian, Dick; Wagtmann, Valery R; Hansen, Soren;

    2015-01-01

    (DCs), we have investigated recall T cell responses in allergic patients sensitized to house dust mite, grass, and birch pollen. Conclusions: Using allergen extract-loaded DCs to stimulate autologous allergen-specific T cell lines, we show that AEC-imprinted DCs inhibit T cell proliferation...... production of both Th1 and Th2 cytokines upon re-challenge. The inhibitory effects of AECs' contact with DCs were absent when allergen extract-loaded DCs had only been exposed to AECs supernatants, but present after direct contact with AECs. We conclude that direct contact between DCs and AECs inhibits T...

  7. Thermokarst rates intensify due to climate change and forest fragmentation in an Alaskan boreal forest lowland

    Science.gov (United States)

    Lara, M.; Genet, Helene; McGuire, Anthony; Euskirchen, Eugénie S.; Zhang, Yujin; Brown, Dana R. N.; Jorgenson, M.T.; Romanovsky, V.; Breen, Amy L.; Bolton, W.R.

    2016-01-01

    Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of

  8. Contributing factors in foliar uptake of dissolved inorganic nitrogen at leaf level

    Energy Technology Data Exchange (ETDEWEB)

    Wuyts, Karen, E-mail: karen.wuyts@uantwerpen.be [Laboratory of Environmental and Urban Ecology, Research Group ENdEMIC, Dept. Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Forest and Nature Lab (ForNaLab), Dept. Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Gontrode-Melle (Belgium); Adriaenssens, Sandy, E-mail: adriaenssens@irceline.be [Belgian Interregional Environment Agency (IRCEL-CELINE), Kunstlaan 10–11, B-1210 Brussels (Belgium); Staelens, Jeroen, E-mail: jeroen_staelens@yahoo.com [Flemish Environment Agency (VMM), Kronenburgstraat 45, B-2000 Antwerp (Belgium); Wuytack, Tatiana, E-mail: tatiana.wuytack@uantwerpen.be [Laboratory of Environmental and Urban Ecology, Research Group ENdEMIC, Dept. Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Van Wittenberghe, Shari, E-mail: shari.vanwittenberghe@uantwerpen.be [Laboratory of Environmental and Urban Ecology, Research Group ENdEMIC, Dept. Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Boeckx, Pascal, E-mail: pascal.boeckx@ugent.be [Isotope Bioscience Laboratory (ISOFYS), Dept. Applied Analytical and Physical Chemistry, Ghent University, Coupure Links 653, B-9000 Ghent (Belgium); Samson, Roeland, E-mail: roeland.samson@uantwerpen.be [Laboratory of Environmental and Urban Ecology, Research Group ENdEMIC, Dept. Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Verheyen, Kris, E-mail: kris.verheyen@ugent.be [Forest and Nature Lab (ForNaLab), Dept. Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, B-9090 Gontrode-Melle (Belgium)

    2015-02-01

    We investigated the influence of leaf traits, rainwater chemistry, and pedospheric nitrogen (N) fertilisation on the aqueous uptake of inorganic N by physiologically active tree leaves. Leaves of juvenile silver birch and European beech trees, supplied with NH{sub 4}NO{sub 3} to the soil at rates from 0 to 200 kg N ha{sup −1} y{sup −1}, were individually exposed to 100 μl of artificial rainwater containing {sup 15}NH{sub 4}{sup +} or {sup 15}NO{sub 3}{sup −} at two concentration levels for one hour. In the next vegetative period, the experiment was repeated with NH{sub 4}{sup +} at the highest concentration only. The N form and the N concentration in the applied rainwater and, to a lesser extent, the pedospheric N treatment and the leaf traits affected the aqueous foliar N uptake. The foliar uptake of NH{sub 4}{sup +} by birch increased when leaves were more wettable. High leaf N concentration and leaf mass per area enhanced the foliar N uptake, and NO{sub 3}{sup −} uptake in particular, by birch. Variation in the foliar N uptake by the beech trees could not be explained by the leaf traits considered. In the first experiment, N fertilisation stimulated the foliar N uptake in both species, which was on average 1.42–1.78 times higher at the highest soil N dose than at the zero dose. However, data variability was high and the effect was not appreciable in the second experiment. Our data suggest that next to rainwater chemistry (N form and concentration) also forest N status could play a role in the partitioning of N entering the ecosystem through the soil and the canopy. Models of canopy uptake of aqueous N at the leaf level should take account of leaf traits such as wettability and N concentration. - Highlights: • Foliar uptake of dissolved inorganic nitrogen (N) by potted trees was studied. • Leaves were individually exposed to rainwater drops containing {sup 15}NH{sub 4}{sup +} or {sup 15}NO{sub 3}{sup −}. • Foliar N uptake efficiency depended on

  9. Analyzing tree cores to detect petroleum hydrocarbon-contaminated groundwater at a former landfill site in the community of Happy Valley-Goose Bay, eastern Canadian subarctic

    DEFF Research Database (Denmark)

    Fonkwe, Merline L D; Trapp, Stefan

    2016-01-01

    This research examines the feasibility of analyzing tree cores to detect benzene, toluene, ethylbenzene, and m, p, o-xylene (BTEX) compounds and methyl tertiary-butyl ether (MTBE) in groundwater in eastern Canada subarctic environments, using a former landfill site in the remote community of Happ...... Valley-Goose Bay, Labrador. Petroleum hydrocarbon contamination at the landfill site is the result of environmentally unsound pre-1990s disposal of households and industrial solid wastes. Tree cores were taken from trembling aspen, black spruce, and white birch and analyzed by headspace...

  10. Contribution of Syringyl β-O-4 Linkage in Different Hardwood Lignin Preparations

    OpenAIRE

    Hori, Keko; Shimizu, Takashi; MESHITSUKA, Gyosuke

    2004-01-01

    Sinapyl alcohol was confirmed as a major product of trimethylsilyl iodide (TMSiI) treatment of syringyl β-O-4 lignin model compound. In this study, contribution of syringyl β-O-4 linkage in different lignin preparations was investigated by comparing the yields of sinapyl alcohol obtained by TMSiI treatment. Milled wood lignin (MWL) produced lower yield of sinapyl alcohol than periodate lignin of birch wood chip, suggesting that MWL was a special part of whole lignin. Periodate lignin of wood ...

  11. Introduction to Distribution and Ecology of Sterile Conks of Inonotus obliquus

    OpenAIRE

    Lee, Min-Woong; Hur, Hyeon; Chang, Kwang-Choon; Lee, Tae-Soo; Ka, Kang-Hyeon; Jankovsky, L.

    2008-01-01

    Inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. This fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (Betula spp). The dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. Chaga are a folk remedy in Russia, reflecting the circumboreal distribution of I. obliquus in boreal forest ecosystems on Betula spp. and in meridional mountain forests on beech (Fagus spp.) in R...

  12. High-pressure X-ray diffraction study on alpha-PbF2

    OpenAIRE

    Ehm, L.; Knorr, K.; Maedler, F.; Voigtlaender, H.; Busetto, E.; Cassetta, A.; Lausi, A.; Winkler, B.

    2002-01-01

    The high-pressure behaviour of alpha-PbF2 has been investigated by angular-dispersive synchrotron X-ray powder diffraction up to 6.55(8) GPa. The fit of a 3rd-order Birch-Murnaghan equation-of-state gave the volume at zero pressure V0=194.14(4)\\AA$^3 and the bulk modulus b_0=47.0(6)GPa with the pressure derivative b'=7.9(4). The continuous-symmetry-measure approach has been used for the quantification of the distortion of the coordination polyhedron in alpha-PbF2 revealing an increasing disto...

  13. Determination of trace amounts of molybdenum in plant tissue by solvent extraction-atomic-absorption and direct-current plasma emission spectrometry.

    Science.gov (United States)

    Lajunen, L H; Kubin, A

    1986-03-01

    Methods are presented for determination of molybdenum in plant tissue by flame and graphite-furnace atomic-absorption spectrometry and direct-current argon-plasma emission spectrometry. The samples are digested in HNO(3)-H(2)SO(4)-HC1O(4) mixture, and Mo is separated and concentrated by chelation and extraction. Three organic solvents (methyl isobutyl ketone, di-isobutyl ketone and isoamyl alcohol) and two ligands (8-hydroxyquinoline and toluene-3,4-dithiol) were studied. The procedure were tested on pine needle and birch leaf samples. PMID:18964076

  14. What do we know about plant food allergens?

    DEFF Research Database (Denmark)

    Jenkins, J. A.; Sancho, A. I.; Madsen, Charlotte Bernhard;

    2005-01-01

    databases has allowed their classification into families. This has shown that plant food allergens fall into four main families, with the prolamin superfamily (including the 2S albumins, nonspecific lipid transfer proteins and cc-amylase inhibitors) predominating, followed by the family of allergens related...... to the major birch pollen allergen, Bet v 1, and the cupin superfamily, including the I IS and 7S seed storage globulins. Future studies will be required to allow us to begin understand what it is about these protein families - whether it be their abundance, stability or some as yet unidentified factor...... - that is predisposing certain family members to becoming allergens....

  15. Studies on Solid Wood. II. The Influence of Chemical Modifications on Viscoelastic Properties

    DEFF Research Database (Denmark)

    Bjørkmann, Anders; Salmén, Lennart

    2000-01-01

    The relation between the properties of wood polymers and those of the composite material of wood is a subject that has been of interest for a long time. In order to increase oar knowledge in this matter, changes of wood properties have been studied on samples of spruce and birch, subjected...... with water, the glass transition was measured by applying sinusoidal vibrations with frequencies of 0.05-20 Hz, giving a transition for each frequency and an apparent activation energy of frequency changes. In wet wood, these quantities characterise the influence of a certain treatment on the properties...

  16. Tree Species Establishment in Urban Forest in Relation to Vegetation Composition, Tree Canopy Gap Area and Soil Factors

    OpenAIRE

    Ilze Jankovska; Guntis Brūmelis; Oļģerts Nikodemus; Raimonds Kasparinskis; Vita Amatniece; Gustavs Straupmanis

    2015-01-01

    The study of density and growth of pine, birch and oak seedlings and saplings in canopy gaps in the urban boreal forest in Riga, Latvia, indicates that natural regeneration can increase diversity in small gaps caused by tree mortality, and can ensure conversion from even-aged pine forest. Abundant regeneration in small gaps showed that light (gap area) was only one of the factors affecting tree regeneration in the gaps. The depth of the O layer and pH were suggested to be important factors fo...

  17. Elliptic Tales Curves, Counting, and Number Theory

    CERN Document Server

    Ash, Avner

    2012-01-01

    Elliptic Tales describes the latest developments in number theory by looking at one of the most exciting unsolved problems in contemporary mathematics--the Birch and Swinnerton-Dyer Conjecture. The Clay Mathematics Institute is offering a prize of 1 million to anyone who can discover a general solution to the problem. In this book, Avner Ash and Robert Gross guide readers through the mathematics they need to understand this captivating problem. The key to the conjecture lies in elliptic curves, which are cubic equations in two variables. These equations may appear simple, yet they arise from

  18. Heegner modules and elliptic curves

    CERN Document Server

    Brown, Martin L

    2004-01-01

    Heegner points on both modular curves and elliptic curves over global fields of any characteristic form the topic of this research monograph. The Heegner module of an elliptic curve is an original concept introduced in this text. The computation of the cohomology of the Heegner module is the main technical result and is applied to prove the Tate conjecture for a class of elliptic surfaces over finite fields; this conjecture is equivalent to the Birch and Swinnerton-Dyer conjecture for the corresponding elliptic curves over global fields.

  19. Equations of state for barium in high-pressure phases

    International Nuclear Information System (INIS)

    The universal equation of state with an arbitrary reference point presented by the author (Fang Zheng-Hua 1998 Phys. Rev. B 50 16 238) is applied successfully to the analysis of the experimental compression data of barium in different structural phases (I, II, and V). The comparison given in this paper shows that this equation suits for the isothermal compression behaviour of barium in the high-pressure phases (II and V) better than the Birch-Murnaghan equation. The applicability of equations of state for solids in high-pressure phases is also discussed. (author)

  20. Inhibition of the growth of Alexandrium tamarense by algicidal substances in Chinese fir (Cunninghamia lanceolata).

    Science.gov (United States)

    Yang, Wei-Dong; Liu, Jie-Sheng; Li, Hong-Ye; Zhang, Xin-Lian; Qi, Yu-Zao

    2009-10-01

    The wood sawdust from Chinese fir (Cunninghamia lanceolata) exhibited stronger inhibition on the growth of Alexandrium tamarense than those from alder (Alnus cremastogyne), pine (Pinus massoniana), birch (Betula alnoides) and sapele (Entandrophragma cylindricum). The water extract, acetone-water extract and essential oil from fir sawdust were all shown to inhibit the growth of A. tamarense. The inhibition of fir essential oil was the strongest among all the above wood sources while the half effective concentration was only 0.65 mg/L. These results suggested that the fir essential oil may play an important role in the algicidal effect of Chinese fir. PMID:19634014