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Sample records for maple seedlings affected

  1. Growth and ABA responses of maple seedlings to aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, A.; Robitaille, G.; Boutin, R. [Canadian Forestry Service, Sainte Foy, PQ (Canada); Nadeau, P. [Agriculture and Agri-Food Canada Research Station, Sainte-Foy, PQ (Canada)

    1995-12-01

    The impacts of low pH and 2.0 mM aluminum (Al) on the growth of sugar maple seedlings was assessed over a 13-week period. The hypothesis was that low pH and high aluminum concentration would lower the vigor of sugar maple seedlings and were contributing factors to sugar maple stand decline. The effects of the stresses were measured in roots and shoots. The concentration of abscisis acid (ABA) in xylem sap in response to Al over time was measured to determine whether it could be used as an indicator of Al stress in sugar maple seedlings. At week 9, total leaf area of Al-treated seedlings was reduced by 27%, but by week 13 leaf area was similar for seedlings in all treatments. None of the other growth parameters examined were negatively affected by the treatments at either week 9 or week 13. ABA concentration in the xylem sap was not affected by any of the treatments. The duration of exposure to Al was found critical when assessing a threshold concentration for Al toxicity because plants can acclimate to an Al concentration previously considered toxic. 36 refs., 1 tab., 6 figs.

  2. Sugar maple and yellow birch seedling growth after simulated browsing.

    Science.gov (United States)

    Frederick T. Metzger

    1977-01-01

    Simulating natural damage to leaders of forest-grown seedlings of yellow birch and sugar maple resulted in no loss of vigor but a loss in net height growth. Leader elongation depended upon seedling, shoot, and bud characteristics rather than on the extent of damage.

  3. Stimulatory effects of aluminum on growth of sugar maple seedlings

    Science.gov (United States)

    George A. Schier; Carolyn J. McQuattie

    2002-01-01

    To determine the effect of aluminum (Al) on sugar maple (Acer saccharum Marsh.), seedlings were grown in sand irrigated with nutrient solution (pH 3.8) containing 0, 2.5, 5, 10, 20, or 40 mg L-1 Al. Seedling growth was enhanced at 2.5 and 5mgL-1 Al. Although higher levels of Al reduced calcium (Ca) and...

  4. Effects of Watering and Fertilization on Carbohydrate Reserves in Sugar Maple Seedlings

    Science.gov (United States)

    Clayton M., Jr. Carl; John R. Donnelly; Boyd W. Post

    1978-01-01

    Sugar maple seedlings, grown under three nutrient and three moisture levels, were analyzed after three growing seasons for starch and ethanol-soluble sugars. Analytical procedures are detailed in the appendix. Fertilization did not affect carbohydrate levels in stems or roots. Water stress caused a significant reduction in the amount of carbohydrates in stems and roots...

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

    Science.gov (United States)

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

    2010-05-01

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

  6. Sugar maple seedling anatomy and element localization at forest sites with differing nutrient levels

    Science.gov (United States)

    Carolyn J. McQuattie; Robert P. Long; Thomas J. Hall

    1999-01-01

    Sugar maple (Acer saccharum Marsh.) seedlings often have poor survival on acidic unglaciated portions of the Allegheny Plateau. Greater survival is found after lime treatment of unglaciated sites or on glaciated areas of the Plateau. The difference in survival rate may depend in part on the acidity or chemical composition of the soil.

  7. Increased seedling establishment via enemy release at the upper elevational range limit of sugar maple.

    Science.gov (United States)

    Urli, Morgane; Brown, Carissa D; Narváez Perez, Rosela; Chagnon, Pierre-Luc; Vellend, Mark

    2016-11-01

    The enemy release hypothesis is frequently invoked to explain invasion by nonnative species, but studies focusing on the influence of enemies on natural plant range expansion due to climate change remain scarce. We combined multiple approaches to study the influence of plant-enemy interactions on the upper elevational range limit of sugar maple (Acer saccharum) in southeastern Québec, Canada, where a previous study had demonstrated intense seed predation just beyond the range limit. Consistent with the hypothesis of release from natural enemies at the range limit, data from both natural patterns of regeneration and from seed and seedling transplant experiments showed higher seedling densities at the range edge than in the core of the species' distribution. A growth chamber experiment manipulating soil origin and temperature indicated that this so-called "happy edge" was not likely caused by temperature (i.e., the possibility that climate warming has made high elevation temperatures optimal for sugar maple) or by abiotic soil factors that vary along the elevational gradient. Finally, an insect-herbivore-exclusion experiment showed that insect herbivory was a major cause of seedling mortality in the core of sugar maple's distribution, whereas seedlings transplanted at or beyond the range edge experienced minimal herbivory (i.e., enemy release). Insect herbivory did not completely explain the high levels of seedling mortality in the core of the species' distribution, suggesting that seedlings at or beyond the range edge may also experience release from pathogens. In sum, while some effects of enemies are magnified beyond range edges (e.g., seed predation), others are dampened at and beyond the range edge (e.g., insect herbivory), such that understanding the net outcome of different biotic interactions within, at and beyond the edge of distribution is critical to predicting species' responses to global change. © 2016 by the Ecological Society of America.

  8. The changes in leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) in response to heavy metal stress

    Science.gov (United States)

    Schwaller, M. R.; Schnetzler, C. C.; Marshall, P. E.

    1981-01-01

    The effects of heavy metal stress on leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) are examined. It is found that sugar maple seedlings treated with anomalous amounts of heavy metals in the rooting medium exhibited an increased leaf reflectance over the entire range of investigated wavelengths, from 475 to 1650 nm. These results conform to those of a previous investigation in the wavelengths from 475 to 660nm, but tend to contradict the previous study in the near infrared wavelengths from 1000 to 1650nm. The differences may possible be due to different water regimes in the two investigations.

  9. The changes in leaf reflectance of sugar maple (Acer saccharum Marsh) seedlings in response to heavy metal stress

    Science.gov (United States)

    Schwaller, M. R.; Schnetzler, C. C.; Marshall, P. E.

    1983-01-01

    The effects of heavy metal stress on leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) are examined. It is found that sugar maple seedlings treated with anomalous amounts of heavy metals in the rooting medium exhibited an increased leaf reflectance over the entire range of investigated wavelengths, from 475 to 1650 nm. These results conform to those of a previous investigation in the wavelengths from 475 to 660 nm, but tend to contradict the previous study in the near infrared wavelengths from 1000 to 1650 nm. The differences may possibly be due to different water regimes in the two investigations. Previously announced in STAR as N81-29729

  10. Effects of elevated [CO2] and low soil moisture on the physiological responses of Mountain Maple (Acer spicatum L. seedlings to light.

    Directory of Open Access Journals (Sweden)

    Gabriel Danyagri

    Full Text Available Global climate change is expected to affect how plants respond to their physical and biological environments. In this study, we examined the effects of elevated CO2 ([CO2] and low soil moisture on the physiological responses of mountain maple (Acer spicatum L. seedlings to light availability. The seedlings were grown at ambient (392 µmol mol(-1 and elevated (784 µmol mol(-1 [CO2], low and high soil moisture (M regimes, at high light (100% and low light (30% in the greenhouse for one growing season. We measured net photosynthesis (A, stomatal conductance (g s, instantaneous water use efficiency (IWUE, maximum rate of carboxylation (V cmax, rate of photosynthetic electron transport (J, triose phosphate utilization (TPU, leaf respiration (R d, light compensation point (LCP and mid-day shoot water potential (Ψx. A and g s did not show significant responses to light treatment in seedlings grown at low soil moisture treatment, but the high light significantly decreased the C i/C a in those seedlings. IWUE was significantly higher in the elevated compared with the ambient [CO2], and the effect was greater at high than the low light treatment. LCP did not respond to the soil moisture treatments when seedlings were grown in high light under both [CO2]. The low soil moisture significantly reduced Ψx but had no significant effect on the responses of other physiological traits to light or [CO2]. These results suggest that as the atmospheric [CO2] rises, the physiological performance of mountain maple seedlings in high light environments may be enhanced, particularly when soil moisture conditions are favourable.

  11. Effects of elevated [CO2] and low soil moisture on the physiological responses of Mountain Maple (Acer spicatum L.) seedlings to light.

    Science.gov (United States)

    Danyagri, Gabriel; Dang, Qing-Lai

    2013-01-01

    Global climate change is expected to affect how plants respond to their physical and biological environments. In this study, we examined the effects of elevated CO2 ([CO2]) and low soil moisture on the physiological responses of mountain maple (Acer spicatum L.) seedlings to light availability. The seedlings were grown at ambient (392 µmol mol(-1)) and elevated (784 µmol mol(-1)) [CO2], low and high soil moisture (M) regimes, at high light (100%) and low light (30%) in the greenhouse for one growing season. We measured net photosynthesis (A), stomatal conductance (g s), instantaneous water use efficiency (IWUE), maximum rate of carboxylation (V cmax), rate of photosynthetic electron transport (J), triose phosphate utilization (TPU)), leaf respiration (R d), light compensation point (LCP) and mid-day shoot water potential (Ψx). A and g s did not show significant responses to light treatment in seedlings grown at low soil moisture treatment, but the high light significantly decreased the C i/C a in those seedlings. IWUE was significantly higher in the elevated compared with the ambient [CO2], and the effect was greater at high than the low light treatment. LCP did not respond to the soil moisture treatments when seedlings were grown in high light under both [CO2]. The low soil moisture significantly reduced Ψx but had no significant effect on the responses of other physiological traits to light or [CO2]. These results suggest that as the atmospheric [CO2] rises, the physiological performance of mountain maple seedlings in high light environments may be enhanced, particularly when soil moisture conditions are favourable.

  12. Responses of sugar maple and hemlock seedlings to elevated carbon dioxide under altered above and below ground nitrogen sources

    International Nuclear Information System (INIS)

    Eller, Allyson S.D.; McGuire, Krista L.; Sparks, Jed

    2011-01-01

    The aim of this study is to determine the influence of CO2, NO2 and nitrate deposition (NO3-) increase at the same time on tree seedlings. Experiments were conducted on sugar maple and eastern hemlock in an open field over a two year period. They were grown under ambient or elevated CO2 and NO2 and with or without wet deposition of NO3-. Results showed that the effects of one treatment can be eliminated by another treatment thus demonstrating these effects are not additive. The growth of both sugar maple and eastern hemlock was found to be similar under the influence of the three treatments and under control conditions. .

  13. Relationships between soluble sugar concentrations in roots and ecosystem stress for first-year sugar maple seedlings

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, J.W.; Reed, D.D.; Jurgensen, M.F.; Mroz, G.D.; Bagley, S.T. [Michigan Technological University, Houghton, MI (United States). School of Forestry and Wood Products

    1996-03-01

    Accumulation of reducing sugars (i.e. glucose and fructose) in plant roots has been consistently correlated with forest dieback and decline and, therefore, has potential as a biological indicator of ecosystem stress. In this study, the relationships between acidic deposition and `natural` (temperature, mycorrhizae, and nutrition) factors with first-year sugar maple seedling root sugar concentrations and growth were assessed in two sugar maple dominated forests in Michigan. Seedlings at the southern site (Wellston) had greater root growth, phosphorus, total sugar, and sucrose concentrations in roots, but lower reducing sugar concentration in roots. In addition, percent root length colonized by vesicular-arbuscular mycorrhizal fungi was less than that found for seedlings growing at the northern site (Alberta). Throughfall deposition of nitrate, sulfate, and hydrogen ions was not significantly correlated with seedling total or reducing sugar concentration. Total sugar concentration in seedling roots was positively correlated with air and soil temperatures at the southern site, but not at the northern site. Seedling tissue phosphorus concentration was correlated with total sugars at both sites, with sucrose at the southern site, and reducing sugars at the northern site. Mycorrhizal colonization rates at the Alberta site were positively correlated with reducing sugar concentration in seedling roots and negatively correlated with sucrose concentration. The results suggest that differences in seedling root sugar concentrations in these two forests are related to seedling root growth and are most likely due to ecological variables, such as available soil phosphorus, temperature, and growing season length through some complex interaction with mycorrhizae rather than acidic deposition stress. 56 refs., 3 figs.

  14. Effect of Sugar Maple Root Exudate on Seedlings of Northern Conifer Species

    Science.gov (United States)

    Carl H. Tubbs

    1976-01-01

    It has been shows that a root exudate of sugar maple reduces the growth of yellow birch. A laboratory test indicated that the growth of northern conifers is also reduced in sugar maple root exudate. Allelopathy may play an important role in survival of species on sites where sugar maple is abundant.

  15. Influence of overstory density on ecophysiology of red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings in central Ontario shelterwoods

    Science.gov (United States)

    William C. Parker; Daniel C. Dey

    2008-01-01

    A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...

  16. Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

    Science.gov (United States)

    Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the

  17. Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh.) Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA.

    Science.gov (United States)

    Momen, Bahram; Behling, Shawna J; Lawrence, Greg B; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the forest floor

  18. Effects of defoliation and drought on root food reserves in sugar maple seedlings

    Science.gov (United States)

    Johnson Parker; Johnson Parker

    1970-01-01

    The artificial defoliation of sugar maple (Acer. saccharum Marsh.) can cause a marked decline in root food reserves, especially starch, and an increase in the levels of the reducing sugars, fructose and glucose. Defoliation can also bring on the dieback-decline syndrome in sugar maples (Parker and Houston 1968). Two experiments designed to examine this question were...

  19. The effect of microbial inocula on the growth of black locust, Siberian elm and silver maple seedlings

    Directory of Open Access Journals (Sweden)

    Hajnal-Jafari Timea

    2014-01-01

    Full Text Available Growth and development of forest plants depend mostly on the soil microbial activity since no mineral or organic fertilizers are applied. Microbial processes can be activated and conditions for plants development improved with the introduction of selected microorganisms in the soil. With the aim of obtaining quality planting material in a shorter period of time, the effects of Azotobacter chroococcum and Streptomyces sp. on the early growth of black locust (Robinia pseudoacacia, Siberian elm (Ulmus pumila and silver-leaf maple (Acer dasycarpum were investigated in this study. Microorganisms were applied individually and in a mixture (1:1. Plant height was measured on the 90th, 120th and 180th day after planting. Plant diameter, as well as the number of actinomycetes and azotobacters was measured at the end of the vegetation period (180 days after planting. Applied microorganisms had a positive effect on the seedling height in all three plant species, with the best effect found in the black locust. Effectiveness of applied microorganisms on seedling diameter was the highest in the silver-leaf maple. The largest number of azotobacters was found in the rhizosphere of black locust. Number of microorganisms from both groups was increased in the inoculated variants. [Projekat Ministarstva nauke Republike Srbije, br. III 43002

  20. Responses of secondary chemicals in sugar maple (Acer saccharum) seedlings to UV-B, springtime warming and nitrogen additions

    Energy Technology Data Exchange (ETDEWEB)

    Sager, E.P.S.; Hutchinson, T.C. [Trent Univ., Peterborough, ON (Canada). Environmental Studies

    2006-10-15

    Elevated UV-B radiation due to climatic change and ozone depletion may represent a significant springtime environmental stressor to germinating seedlings in temperate forest regions. This study aimed to determine the effects of UV-B, nitrogen (N) fertilization and climate warming on the concentrations of base cations and secondary metabolites in the foliage of sugar maple seedlings growing in acid or alkaline soils. The influence of measured flavonoids and phenolics on herbivore activity was examined, as well as the relationship between foliar concentrations of calcium (Ca); manganese (Mn); and N and the production of phenolic and flavonoid compounds. Experimental plots were established in mature hardwood forests in alkaline and acid soil locations in Bobcaygeon and Haliburton, Ontario. Pentagonal open-top chambers were used to lengthen the growing season and simulate an earlier spring. Ammonium nitrate was applied at a rate comparable with an additional deposition of 5 g N per m per year. Fertilizer was applied on 3 separate occasions. Ambient UV-B radiation was screened out with Mylar D polyester film. Sites, treatments and time of sampling had complex effects on foliar elemental chemistry, production of secondary compounds and herbivory. Foliar concentrations of individual phenols were higher in seedlings in the UV-B exclusion treatments. At both sites, removal of ambient UV-B led to increases in flavonoids and chlorogenic acid, and reduced herbivore activity. At Haliburton, ammonium nitrate fertilization led to further increases in foliar Mn. Nitrogen additions led to decreases in the concentrations of some flavonoids at both sites. It was concluded that the composition of the forest soil governs the response of seedlings when they are exposed to abiotic stressors. 63 refs., 5 tabs., 8 figs.

  1. Responses of hybrid poplar clones and red maple seedlings to ambient O3 under differing light within a mixed hardwood forest

    International Nuclear Information System (INIS)

    Wei, C.; Skelly, J.M.; Pennypacker, S.P.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.; Davis, D.D.

    2004-01-01

    The responses of ramets of hybrid poplar (Populus spp.) (HP) clones NE388 and NE359, and seedlings of red maple (Acer rubrum, L.) to ambient ozone (O 3 ) were studied during May-September of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). Ambient O 3 concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. Monthly 12-h average O 3 concentrations ranged from 32.3 to 52.9 ppb. Weekly 12-h average photosynthetically active radiation (PAR) within the sun, partial shade and full shade plots ranged from 200 to 750, 50 to 180, and 25 to 75 μmol m -2 s -1 , respectively. Ambient O 3 exposure induced visible foliar symptoms on HP NE388 and NE359 in both growing seasons, with more severe injury observed on NE388 than on NE359. Slight foliar symptoms were observed on red maple seedlings during the 2001growing season. Percentage of total leaf area affected (%LAA) was positively correlated with cumulative O 3 exposures. More severe foliar injury was observed on plants grown within the full shade and partial shade plots than those observed on plants grown within the sun plot. Lower light availability within the partial shade and full shade plots significantly decreased net photosynthetic rate (Pn) and stomatal conductance (g wv ). The reductions in Pn were greater than reductions in g wv , which resulted in greater O 3 uptake per unit Pn in plants grown within the partial shade and full shade plots. Greater O 3 uptake per unit Pn was consistently associated with more severe visible foliar injury in all species and/or clones regardless of differences in shade tolerance. These studies suggest that plant physiological responses to O 3 exposure are likely complicated due to multiple factors under natural forest conditions. - Under natural forest conditions and ambient O 3 exposures, available light plays a significant role in determining O 3 uptake and

  2. Liming Influences Growth and Nutrient Balances in Sugar Maple (Acer saccharum) Seedlings on an Acidic Forest Soil

    Science.gov (United States)

    Dudley J. Raynal

    1998-01-01

    Forests in the northeastern US have been limed to mitigate soil acidification and the acidity of surface waters and to improve soil base cation status. Much of the area considered for liming is within the range of sugar maple (Acer saccharum), but there is a poor understanding of how liming influences growth and nutrient balance of this species on...

  3. Widespread sugar maple decline and regeneration failure in the Adirondacks

    Science.gov (United States)

    Jerry C. Jenkins; Elizabeth Moffett; Daphne Ross

    1999-01-01

    Over large areas of the Adirondacks, hardwood stands whose canopies are dominated by or contain abundant mature sugar maple (Acer saccharum Marsh.) have almost no sugar maple saplings or seedlings in the understory.

  4. A sugar maple planting study in Vermont

    Science.gov (United States)

    Harry W. Yawney; Clayton M., Jr. Carl; Clayton M. Carl

    1970-01-01

    Past attempts to establish sugar maple (Acer saccharum Marsh.) by planting have generally met with little success. The failures have been blamed mainly on competition by other vegetation and on damage done by animals. Finding an effective way to establish sugar maple seedlings is a key part in the research being carried on in Vermont by the USDA Forest Service to...

  5. Grass defoliation affecting survival and growth of seedlings of ...

    African Journals Online (AJOL)

    Two experiments were conducted, one in the field and the other in the greenhouse, to investigate the effects of the intensity and frequency of grass defoliation on the survival and growth of Acacia karroo seedlings. In the greenhouse, seedlings growing with heavily clipped grasses had higher biomass production than those ...

  6. Analysis on Factors Affecting Seedling Establishment in Rice

    Directory of Open Access Journals (Sweden)

    Ju LUO

    2007-03-01

    Full Text Available Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96–21 with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted lognormal distribution. Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl × coleoptile, seeding depth, flooding duration and mesocotyl × sowing depth in the experiment for seedling establishment.

  7. Factors affecting acorn production and germination and early growth of seedlings and seedling sprouts

    Science.gov (United States)

    David F. Olson; Stephen G. Boyce

    1971-01-01

    Acorn production is extremely variable and unpredictable. Flowering is copious, but many climatic factors influence acorn development from initiation of flowers to acorn maturity. Acorns are consumed by birds, animals, insects, and microorganisms. The establishment of seedlings is more closely related to favorable site factors than to size of crops. A majority of oaks...

  8. Water application rate and frequency affect seedling survival and ...

    African Journals Online (AJOL)

    Adequate amount of water is critical to successful tree nursery operation among resource-constrained smallholder farmers in Africa. Two experiments were undertaken with the objectives of evaluating effects of water application rate and frequency on seedling growth and survival of Persea americana and Vangueria ...

  9. Starch bioengineering affects cereal grain germination and seedling establishment

    DEFF Research Database (Denmark)

    Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...... structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics...... showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated...

  10. Organic matter loading affects lodgepole pine seedling growth.

    Science.gov (United States)

    Wei, Xiaohua; Li, Qinglin; Waterhouse, M J; Armleder, H M

    2012-06-01

    Organic matter plays important roles in returning nutrients to the soil, maintaining forest productivity and creating habitats in forest ecosystems. Forest biomass is in increasing demand for energy production, and organic matter has been considered as a potential supply. Thus, an important management question is how much organic matter should be retained after forest harvesting to maintain forest productivity. To address this question, an experimental trial was established in 1996 to evaluate the responses of lodgepole pine seedling growth to organic matter loading treatments. Four organic matter loading treatments were randomly assigned to each of four homogeneous pine sites: removal of all organic matter on the forest floor, organic matter loading quantity similar to whole-tree-harvesting residuals left on site, organic matter loading quantity similar to stem-only-harvesting residuals, and organic matter loading quantity more similar to what would be found in disease- or insect-killed stands. Our 10-year data showed that height and diameter had 29 and 35 % increase, respectively, comparing the treatment with the most organic matter loading to the treatment with the least organic matter loading. The positive response of seedling growth to organic matter loading may be associated with nutrients and/or microclimate change caused by organic matter, and requires further study. The dynamic response of seedling growth to organic matter loading treatments highlights the importance of long-term studies. Implications of those results on organic matter management are discussed in the context of forest productivity sustainability.

  11. Factors Affecting Planting Depth and Standing of Rice Seedling in Parachute Rice Transplanting

    Science.gov (United States)

    Astika, I. W.; Subrata, I. D. M.; Pramuhadi, G.

    2018-05-01

    Parachute rice transplanting is a simple and practical rice transplanting method. It can be done manually or mechanically, with various possible designs of machines or tools. This research aimed at quantitatively formulating related factors to the planting depth and standing of rice seedling. Parachute seedlings of rice were grown at several sizes of parachute soil bulb sizes. The trays were specially designed with a 3D printer having bulb sizes 7, 8, 9, 10 mm in square sides and 15 mm depth. At seedling ages of 8-12 days after sowing the seedling bulbs were drops into puddled soil. Soil hardness was set at 3 levels of hardness, measured in hardness index using golf ball test. Angle of dropping was set at 3 levels: 0°, 30°and 45° from the vertical axis. The height of droppings was set at 100 cm, 75 cm, and 50 cm. The relationship between bulb size, height of dropping, soil hardness, dropping angle and planting depth was formulated with ANN. Most of input variables did not significantly affect the planting depth, except that hard soil significantly differs from mild soil and soft soil. The dropping also resulted in various positions of the planted seedlings: vertical standing, sloped, and falling. However, at any position of the planted seedlings, the seedlings would recover themselves into normally vertical position. With this result, the design of planting machinery, as well as the manual planting operation, can be made easier.

  12. Understanding Maple

    CERN Document Server

    Thompson, Ian

    2016-01-01

    Maple is a powerful symbolic computation system that is widely used in universities around the world. This short introduction gives readers an insight into the rules that control how the system works, and how to understand, fix, and avoid common problems. Topics covered include algebra, calculus, linear algebra, graphics, programming, and procedures. Each chapter contains numerous illustrative examples, using mathematics that does not extend beyond first-year undergraduate material. Maple worksheets containing these examples are available for download from the author's personal website. The book is suitable for new users, but where advanced topics are central to understanding Maple they are tackled head-on. Many concepts which are absent from introductory books and manuals are described in detail. With this book, students, teachers and researchers will gain a solid understanding of Maple and how to use it to solve complex mathematical problems in a simple and efficient way.

  13. Warming and neighbor removal affect white spruce seedling growth differently above and below treeline.

    Science.gov (United States)

    Okano, Kyoko; Bret-Harte, M Syndonia

    2015-01-01

    Climate change is expected to be pronounced towards higher latitudes and altitudes. Warming triggers treeline and vegetation shifts, which may aggravate interspecific competition and affect biodiversity. This research tested the effects of a warming climate, habitat type, and neighboring plant competition on the establishment and growth of white spruce (Picea glauca (Moench) Voss) seedlings in a subarctic mountain region. P. glauca seedlings were planted in June 2010 under 4 different treatments (high/control temperatures, with/without competition) in 3 habitats (alpine ridge above treeline/tundra near treeline /forest below treeline habitats). After two growing seasons in 2011, growth, photosynthesis and foliar C and N data were obtained from a total of 156, one-and-a-half year old seedlings that had survived. Elevated temperatures increased growth and photosynthetic rates above and near treeline, but decreased them below treeline. Competition was increased by elevated temperatures in all habitat types. Our results suggest that increasing temperatures will have positive effects on the growth of P. glauca seedlings at the locations where P. glauca is expected to expand its habitat, but increasing temperatures may have negative effects on seedlings growing in mature forests. Due to interspecific competition, possibly belowground competition, the upslope expansion of treelines may not be as fast in the future as it was the last fifty years.

  14. Soil Type Affects Pinus ponderosa var. scopulorum (Pinaceae Seedling Growth in Simulated Drought Experiments

    Directory of Open Access Journals (Sweden)

    Alexander J. Lindsey

    2013-07-01

    Full Text Available Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite, a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. Conclusions: Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies.

  15. Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments.

    Science.gov (United States)

    Lindsey, Alexander J; Kilgore, Jason S

    2013-08-01

    Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. • Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite), a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering) produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. • Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies.

  16. Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments1

    Science.gov (United States)

    Lindsey, Alexander J.; Kilgore, Jason S.

    2013-01-01

    • Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. • Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite), a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering) produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. • Conclusions: Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies. PMID:25202578

  17. Recruitment dynamics mediated by ungulate herbivory can affect species coexistence for tree seedling assemblages

    Directory of Open Access Journals (Sweden)

    Chi-Yu Weng

    2017-08-01

    Full Text Available The best-known mechanism that herbivory affects species coexistence of tree seedlings is negative density-dependency driven by specialist natural enemies. However, in a forest with intense herbivory by non-specialists, what causes a diversifying seedling bank if rare species do not benefit from negative density-dependency in dominant species? We hypothesize that generalist herbivores can cause unevenly distributed species-specific mortality, which mediates recruitment dynamics and therefore affects species coexistence. To answer this question, we conducted a fence-control experiment in a montane cloud forest, Taiwan, and found that herbivorous damages were mainly caused by ungulates, which are generalists. We explored ungulate herbivory effects on recruitment dynamics by censusing tree seedling dynamics for three years. We found that herbivorous damages by ungulates significantly cause seedling death, mostly at their early stage of establishment. The percentage of death caused by herbivory varied among species. In particular, nurse plants and seedling initial height help shade-tolerant species to persist under such intense herbivory. Whereas, deaths caused by other factors occurred more often in older seedlings, with a consistent low percentage among species. We then tested species coexistence maintenance by dynamic modelling under different scenarios of ungulate herbivory. Raising percentages of death by herbivory changes relative species abundances by suppressing light-demanding species and increasing shade-tolerant species. Density-dependent mortality immediately after bursts of recruitments can suppress dominance of abundant species. With ungulate herbivory, fluctuating recruitment further prevent rare species from apparent competition induced by abundant species. Such bio-processes can interact with ungulate herbivory so that long-term coexistence can be facilitated.

  18. Norway maple displays greater seasonal growth and phenotypic plasticity to light than native sugar maple.

    Science.gov (United States)

    Paquette, Alain; Fontaine, Bastien; Berninger, Frank; Dubois, Karine; Lechowicz, Martin J; Messier, Christian; Posada, Juan M; Valladares, Fernando; Brisson, Jacques

    2012-11-01

    Norway maple (Acer platanoides L), which is among the most invasive tree species in forests of eastern North America, is associated with reduced regeneration of the related native species, sugar maple (Acer saccharum Marsh) and other native flora. To identify traits conferring an advantage to Norway maple, we grew both species through an entire growing season under simulated light regimes mimicking a closed forest understorey vs. a canopy disturbance (gap). Dynamic shade-houses providing a succession of high-intensity direct-light events between longer periods of low, diffuse light were used to simulate the light regimes. We assessed seedling height growth three times in the season, as well as stem diameter, maximum photosynthetic capacity, biomass allocation above- and below-ground, seasonal phenology and phenotypic plasticity. Given the north European provenance of Norway maple, we also investigated the possibility that its growth in North America might be increased by delayed fall senescence. We found that Norway maple had significantly greater photosynthetic capacity in both light regimes and grew larger in stem diameter than sugar maple. The differences in below- and above-ground biomass, stem diameter, height and maximum photosynthesis were especially important in the simulated gap where Norway maple continued extension growth during the late fall. In the gap regime sugar maple had a significantly higher root : shoot ratio that could confer an advantage in the deepest shade of closed understorey and under water stress or browsing pressure. Norway maple is especially invasive following canopy disturbance where the opposite (low root : shoot ratio) could confer a competitive advantage. Considering the effects of global change in extending the potential growing season, we anticipate that the invasiveness of Norway maple will increase in the future.

  19. Maple sap predominant microbial contaminants are correlated with the physicochemical and sensorial properties of maple syrup.

    Science.gov (United States)

    Filteau, Marie; Lagacé, Luc; Lapointe, Gisèle; Roy, Denis

    2012-03-01

    Maple sap processing and microbial contamination are significant aspects that affect maple syrup quality. In this study, two sample sets from 2005 and 2008 were used to assess the maple syrup quality variation and its relationship to microbial populations, with respect to processing, production site and harvesting period. The abundance of maple sap predominant bacteria (Pseudomonas fluorescens group and two subgroups, Rahnella spp., Janthinobacterium spp., Leuconostoc mesenteroides) and yeast (Mrakia spp., Mrakiella spp.,Guehomyces pullulans) was assessed by quantitative PCR. Maple syrup properties were analyzed by physicochemical and sensorial methods. Results indicate that P. fluorescens, Mrakia spp., Mrakiella spp. G. pullulans and Rahnella spp. are stable contaminants of maple sap, as they were found for every production site throughout the flow period. Multiple factor analysis reports a link between the relative abundance of P. fluorescens group and Mrakia spp. in maple sap with maple and vanilla odor as well as flavor of maple syrup. This evidence supports the contribution of these microorganisms or a consortium of predominant microbial contaminants to the characteristic properties of maple syrup. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Altering the axial light gradient affects photomorphogenesis in emerging seedlings of Zea mays L

    Science.gov (United States)

    Parks, B. M.; Poff, K. L.

    1986-01-01

    The axial (longitudinal) red light gradient (632 nanometers) of 4 day old dark-grown maize seedlings is increased by staining the peripheral cells of the coleoptile. The magnitude of increase in the light gradient is dependent solely on the light-absorbing qualities of the stain used. Metanil yellow has no effect on the axial red-light gradient, while methylene blue causes a large increase in this light gradient. These stains did not affect growth in darkness or the sensitivity of mesocotyl elongation to red light. However, mesocotyl elongation was altered for the dark-grown seedlings stained with methylene blue when these seedlings were transplanted, covered with soil, and permitted to emerge under natural lighting conditions. These observations are consistent with the idea that there is a single perceptive site below the coleoptilar node, and suggest that this perceptive site gives the actinic light which has traveled downward through the length of the shoot from an entry point in the plant tip region.

  1. Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone

    International Nuclear Information System (INIS)

    Schaub, M.; Skelly, J.M.; Steiner, K.C.; Davis, D.D.; Pennypacker, S.P.; Zhang, J.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E.

    2003-01-01

    High soil water availability favors ozone uptake, increases foliar injury, and exacerbates the negative ozone effect on gas exchange of seedlings of deciduous tree species. - Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O 3 ; non-filtered air: 98% ambient O 3 ; charcoal-filtered air: 50% ambient O 3 ) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data, ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (<34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures

  2. Silvical characteristics of red maple (Acer rubrum)

    Science.gov (United States)

    Russell J. Hutnik; Harry W. Yawney

    1961-01-01

    Red maple (Acer rubrum L.) is also known as Carolina red maple, scarlet maple, soft maple, swamp maple, water maple, and white maple. Taxonomists recognize several varieties of red maple. The most common is Drummond red maple (Acer rubrum var. drummondii (Hook, & Arn.) Sarg.).

  3. Maple syrup urine disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000373.htm Maple syrup urine disease To use the sharing features on this page, please enable JavaScript. Maple syrup urine disease (MSUD) is a disorder in ...

  4. Air lateral root pruning affects longleaf pine seedling root system morphology

    Science.gov (United States)

    Shi-Jean Susana Sung; Dave Haywood

    2016-01-01

    Longleaf pine (Pinus palustris) seedlings were cultured with air lateral root pruning (side-vented containers, VT) or without (solid-walled containers, SW). Seedling root system morphology and growth were assessed before planting and 8 and 14 months after planting. Although VT seedlings had greater root collar diameter than the SW before planting,...

  5. Ray tissues as an indirect measure of relative sap-sugar concentration in sugar maple

    Science.gov (United States)

    Peter W. Garrett; Kenneth R. Dudzik; Kenneth R. Dudzik

    1989-01-01

    Attempts to correlate ray tissue as a percentage of total wood volume with sap-sugar concentrations of sugar maple progenies were unsuccessful. These results raise doubts about our ability to use a relatively constant value such as ray-tissue volume in a selection program designed to increase the sap-sugar concentration of sugar maple seedlings.

  6. Maple by example

    CERN Document Server

    Abell, Martha L

    2005-01-01

    Maple by Example, Third Edition, is a reference/text with CD for beginning and experienced students, professional engineers, and other Maple users. This new edition has been updated to be compatible with the most recent release of the Maple software. Coverage includes built-in Maple commands used in courses and practices that involve calculus, linear algebra, business mathematics, ordinary and partial differential equations, numerical methods, graphics and more. The CD-ROM provides updated Maple input and all text from the book.* Updated coverage of Maple features and functions * Backwards compatible for all versions* New applications from a variety of fields, including biology, physics and engineering* Expanded topics with many additional examples

  7. The Maple Sugar Festival

    Science.gov (United States)

    Johnston, Basil

    1978-01-01

    Describing the Iroquoi's Maple Sugar Festival, this article details the symbolism of renewal, becoming, and regeneration celebrated by the Iroquoi as the sap from the maple trees begins to flow each year. The symbolic role of woman, the sweet sap itself, and man's fellow creatures are described. (JC)

  8. Growth and Wood/Bark Properties of Abies faxoniana Seedlings as Affected by Elevated CO2

    Institute of Scientific and Technical Information of China (English)

    Yun-Zhou Qiao; Yuan-Bin Zhang; Kai-Yun Wang; Qian Wang; Qi-Zhuo Tian

    2008-01-01

    Growth and wood and bark properties of Abies faxoniana seedlings after one year's exposure to elevated CO2 concentration (ambient + 350 (=1= 25) μmol/mol) under two planting densities (28 or 84 plants/mz) were investigated in closed-top chambers. Tree height, stem diameter and cross-sectional area, and total biomass were enhanced under elevated CO2 concentration, and reduced under high planting density. Most traits of stem bark were improved under elevated CO2 concentration and reduced under high planting density. Stem wood production was significantly increased in volume under elevated CO2 concentration under both densities, and the stem wood density decreased under elevated CO2 concentration and increased under high planting density. These results suggest that the response of stem wood and bark to elevated CO2 concentration is density dependent. This may be of great importance in a future CO2 enriched world in natural forests where plant density varies considerably. The results also show that the bark/wood ratio in diameter, stem cross-sectional area and dry weight are not proportionally affected by elevated CO2 concentration under the two contrasting planting densities. This indicates that the response magnitude of stem bark and stem wood to elevated CO2 concentration are different but their response directions are the same.

  9. Can environmental variation affect seedling survival of plants in northeastern Mexico?

    Directory of Open Access Journals (Sweden)

    García Jaime F.

    2011-01-01

    Full Text Available The effects of global warming increase the frequency and intensity of many climate events such as rainfall. We evaluated the effects of environmental conditions on early stage seedling survival of the native thorn scrub species Caesalpinia mexicana A. Gray, Celtis pallida Torr., Cordia boissieri A. DC., and Ebenopsis ebano (Berland. Barneby and J.W. Grimes, during the summer of 2009 and 2010. The experimental design had two factors, two levels of rainfall and three microhabitats of thorn scrub: (i open interspace, (ii thorn scrub edge and (iii under the canopy of dense thorn scrub. In dense thorn scrub, seedling survival was higher for Caesalpinia mexicana and Celtis pallida, and for Cordia boissieri and Ebenopsis ebano seedling survival was higher in dense thorn scrub and thorn scrub edge. The effect of rainfall on seedling survival depended on the year. Rainfall in 2010 and dense thorn scrub increased seedling survival of native species. For survival, the limiting factors of microhabitats appear to change across the years. Besides rainfall events, biological aspects like competition and mycorrhiza effects would need to be considered in models of plant establishment.

  10. Low glyphosate rates do not affect Citrus limonia (L.) Osbeck seedlings.

    Science.gov (United States)

    Gravena, Renan; Victoria Filho, Ricardo; Alves, Pedro Luis Ca; Mazzafera, Paulo; Gravena, Adriana R

    2009-04-01

    Glyphosate is used to control weeds in citrus orchards, and accidental spraying or wind drift onto the seedlings may cause growth arrest owing to metabolism disturbance. Two experiments were carried out to investigate the effect of non-lethal rates (0, 180, 360 and 720 g AI ha(-1)) of glyphosate on four-month-old 'Cravo' lime, Citrus limonia (L.) Osbeck, seedlings. Photosynthesis and the concentrations of shikimic acid, total free amino acids and phenolic acids were evaluated. Only transitory effects were observed in the contents of shikimate and total free amino acids. No visual effects were observed. The present study showed that glyphosate at non-lethal rates, which is very usual when accidental spraying or wind drift occurs in citrus orchard, did not cause severe metabolic damage in 'Cravo' lime seedlings. Copyright (c) 2009 Society of Chemical Industry.

  11. Acid-base status of upper rooting zone soil in declining and non-declining sugar maple (Acer saccharum Marsh) stands in Pennsylvania

    Science.gov (United States)

    William E. Sharpe; Troy L. Sunderland

    1995-01-01

    Sugar maple (Acer saccharum Marsh) is an important commercial tree species of the central hardwood region which is valued for its wood and maple sugar products. High elevation sugar maple stands in northcentral Pennsylvania have been in serious decline for about the last 15 years with more than 1,200 hectares of maple forest affected. The decline...

  12. Seed and seedling traits affecting critical life stage transitions and recruitment outcomes in dryland grasses

    Science.gov (United States)

    1. Seeding native plants is a key management practice to counter land degradation across the globe, yet the majority of seeding efforts fail, limiting the ability of this tool to accelerate ecosystem recovery. 2. Seedling recruitment requires transitions through several life stages, some of which ma...

  13. Overstory removal and residue treatments affect soil surface, air, and soil temperature: implications for seedling survival

    Science.gov (United States)

    Roger D. Hungerford; Ronald E. Babbitt

    1987-01-01

    Potentially lethal ground surface temperatures were measured at three locations in the Northern Rocky Mountains but occurred more frequently under treatments with greater overstory removal. Observed maximum and minimum temperatures of exposed surfaces are directly related to the thermal properties of the surface materials. Survival of planted seedlings was consistent...

  14. Insects affecting establishment of northern red oak seedlings in central Pennsylvania

    Science.gov (United States)

    J. Galford; L.R. Auchmoody; H.C. Smith; R.S. Walters

    1991-01-01

    Studies to evaluate the impact of insects on the establishment of advance oak regeneration in Pennsylvania were initiated in 1989. The populations and species of insects feeding on germinating acorns and new seedlings, their activity periods, and the damage caused by these insects were studied in relation to overstory-density (40, 60, and 100 percent relative density)...

  15. Leaf age affects the responses of foliar injury and gas exchange to tropospheric ozone in Prunus serotina seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jianwei, E-mail: jianweizhang@fs.fed.u [Environmental Resources Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); School of Forest Resources, Pennsylvania State University, University Park, PA 16802 (United States); Schaub, Marcus; Ferdinand, Jonathan A. [Environmental Resources Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Skelly, John M. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States); Steiner, Kim C. [School of Forest Resources, Pennsylvania State University, University Park, PA 16802 (United States); Savage, James E. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States)

    2010-08-15

    We investigated the effect of leaf age on the response of net photosynthesis (A), stomatal conductance (g{sub wv}), foliar injury, and leaf nitrogen concentration (N{sub L}) to tropospheric ozone (O{sub 3}) on Prunus serotina seedlings grown in open-plots (AA) and open-top chambers, supplied with either carbon-filtered or non-filtered air. We found significant variation in A, g{sub wv}, foliar injury, and N{sub L} (P < 0.05) among O{sub 3} treatments. Seedlings in AA showed the highest A and g{sub wv} due to relatively low vapor pressure deficit (VPD). Older leaves showed significantly lower A, g{sub wv}, N{sub L}, and higher foliar injury (P < 0.001) than younger leaves. Leaf age affected the response of A, g{sub wv}, and foliar injury to O{sub 3}. Both VPD and N{sub L} had a strong influence on leaf gas exchange. Foliar O{sub 3}-induced injury appeared when cumulative O{sub 3} uptake reached 8-12 mmol m{sup -2}, depending on soil water availability. The mechanistic assessment of O{sub 3}-induced injury is a valuable approach for a biologically relevant O{sub 3} risk assessment for forest trees. - Ozone effects on symptom development and leaf gas exchange interacted with leaf age and N-content on black cherry seedlings.

  16. Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments 1

    OpenAIRE

    Lindsey, Alexander J.; Kilgore, Jason S.

    2013-01-01

    Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite), a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering) produced less sh...

  17. Some physiological changes in faba bean seedlings as affected by the treatment with the fungicide zineb

    International Nuclear Information System (INIS)

    Kamel, H.A.; Aly, M.A.S.; Afifi, L.M.

    2002-01-01

    The toxic effect of 10 ppm of the fungicide zineb (zine ethylene -1,2-bis dithiocarbamate) on photosynthesis, respiration and endogenous hormones levels of faba bean seedlings were studied after seed treatment or foliar application utilizing radiotracer techniques. A suggested scheme for faba bean treatment with zineb and a flow diagram for extraction, purification and separation of endogenous hormones are presented. The data obtained (seed treatment) revealed a marked reduction (41.8%) in the amount of 14C O 2 fixed or incorporated in different cell components of seedlings. On the other hand, respiratory activity was significantly increased recording 176.5% and manifesting a respired/fixed radio about 4 times of the corresponding control. In case of foliar application, the amount of 14C O 2 fixed showed remarkable decrease (50%) after 24 h of application then declined to reach almost control values after 72 h. The respiratory 14C O 2 showed a continuos increase with time reaching 398% after 72 h. Respired/fixed ratio amounted 0.8 after 72 h. Both treatments led to an increase in the amounts of endogenous hormones; cytokinines, auxins and ABA when compared with control values recording the highest values after 24 h. A substational reduction in the amount of gibberellin-like substances was observed. Zineb induced high stress on faba bean seedlings and had the impact to reduce the intensity of certain natural processes such as photosynthesis and respiration and increased the endogenous hormones

  18. Effects of Nitrogen Fertilization on Potato Leafhopper (Hemiptera: Cicadellidae) and Maple Spider Mite (Acari: Tetranychidae) on Nursery-Grown Maples.

    Science.gov (United States)

    Prado, Julia; Quesada, Carlos; Gosney, Michael; Mickelbart, Michael V; Sadof, Clifford

    2015-06-01

    Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. MAPLE deposition of nanomaterials

    International Nuclear Information System (INIS)

    Caricato, A.P.; Arima, V.; Catalano, M.; Cesaria, M.; Cozzoli, P.D.; Martino, M.; Taurino, A.; Rella, R.; Scarfiello, R.; Tunno, T.; Zacheo, A.

    2014-01-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  20. MAPLE deposition of nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P., E-mail: annapaola.caricato@le.infn.it [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Arima, V.; Catalano, M. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Cesaria, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Cozzoli, P.D. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Martino, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Taurino, A.; Rella, R. [Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, I-73100 Lecce (Italy); Scarfiello, R. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Tunno, T. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Zacheo, A. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy)

    2014-05-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  1. Storage requirements for sugar maple seeds

    Science.gov (United States)

    Harry W. Yawney; Clayton M., Jr. Carl

    1974-01-01

    Sugar maple seeds, collected from three trees in northern Vermont, were stored at four temperatures (18, 7, 2, and -10ºC) in combination with four seed moisture contents (35, 25, 17, and 10 percent). Seed moisture content and storage temperature significantly affected keeping ability, and these factors were highly interrelated. Seeds from all trees kept best...

  2. Seedling Composition and Facilitative Effects of the Herbaceous Layer in a Monsoon-Affected Forest in Nanjenshan, Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Su-Wei Fan

    2010-11-01

    Full Text Available Tree seedlings play an important role in forest regeneration. To understand the factors that control seedling establishment, we (1 compared the composition patterns of tree seedlings and their corresponding overstories, (2 examined the relationships between seedling composition and environmental factors and (3 evaluated the interaction (competition or facilitation between seedlings and herbaceous layer in a wind-stressed forest in Nanjenshan, southern Taiwan. In the study plot, seedling abundance of canopy, subcanopy and shrub species (with true leaves and < 1 cm diameter at breast height and coverage of herbaceous species (including herbaceous species, climbers and tree ferns ≤ ca. 1 m in height were investigated on three transects with a total of 180 contiguous 5 × 5 m quadrats. Clustering classification and ordination methods were used to reveal the tree seedling composition patterns and the relationships between seedling composition and environmental factors. Correlation coefficients were computed between herbaceous coverage and seedling abundance among herb-seedling species pairs and between tall (≥ 1 m high/short (< 0.5 m high herbs and seedlings pairs to test the herb-seedling interaction. The spatial distribution of tree seedlings presented a perfect match to the overstory vegetation pattern. There was a strong relationship among seedling composition, herbaceous composition and topographic features, especially exposure to monsoon winds. Because of the absence of strong correlations between herbaceous structure/species and seedling abundances, the strong linkage in spatial patterns between seedling and herbaceous compositions suggests that certain plant species in the study plot have similar responses to the monsoon exposure. Our results also indicated that seedlings < 1 cm in diameter were strongly influenced by wind stress, similar to the response of the overstory composition, and that the facilitative/competitive effects of the

  3. 7 CFR 1437.107 - Maple sap.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Maple sap. 1437.107 Section 1437.107 Agriculture... Yield Coverage Using Actual Production History § 1437.107 Maple sap. (a) NAP assistance for maple sap is limited to maple sap produced on private property for sale as sap or syrup. Eligible maple sap must be...

  4. 21 CFR 168.140 - Maple sirup.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Maple sirup. 168.140 Section 168.140 Food and... § 168.140 Maple sirup. (a) Maple sirup is the liquid food derived by concentration and heat treatment of the sap of the maple tree (Acer) or by solution in water of maple sugar (mapel concrete) made from...

  5. Equivalent Colorings with "Maple"

    Science.gov (United States)

    Cecil, David R.; Wang, Rongdong

    2005-01-01

    Many counting problems can be modeled as "colorings" and solved by considering symmetries and Polya's cycle index polynomial. This paper presents a "Maple 7" program link http://users.tamuk.edu/kfdrc00/ that, given Polya's cycle index polynomial, determines all possible associated colorings and their partitioning into equivalence classes. These…

  6. Hylastes ater (Curculionidae: Scolytinae Affecting Pinus radiata Seedling Establishment in New Zealand

    Directory of Open Access Journals (Sweden)

    Stephen D. Reay

    2012-01-01

    Full Text Available The introduced pine bark beetle Hylastes ater has been present in New Zealand for around 100 years. The beetle has been a minor pest on pines. Research was undertaken to control the pest in the 1950s–1970s, with a biological control agent introduced with limited success. Following a reasonably long period with minimal research attention, renewed interest in developing a better understanding of the pest status was initiated in the mid to late 1990s. Subsequently, a significant amount of research was undertaken, with a number of studies exploring the role of this pest of exotic forests in New Zealand. These studies ranged from attempting to quantify damage to seedlings, evaluate the role of the beetle in vectoring sapstain fungi, explore options for management, and evaluate the potential for chemical and biological control. From these studies, a number of findings were made that are relevant to the New Zealand exotic forest industry and shed new light onto the role of secondary bark beetles globally.

  7. Light affects the chloroplast ultrastructure and post-storage photosynthetic performance of watermelon (Citrullus lanatus) plug seedlings.

    Science.gov (United States)

    Duan, Qingqing; Jiang, Wu; Ding, Ming; Lin, Ye; Huang, Danfeng

    2014-01-01

    Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m(-2)·s(-1) or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the chloroplasts. In contrast, the chloroplasts stored in the light were relatively normal. As a result, the light-stored seedlings had a significantly higher chlorophyll content, Fv/Fm, and Pn than did dark-stored seedlings. Regardless of whether the seedlings were stored in light or darkness, the Gs and Ls of the seedlings significantly decreased, while the Ci obviously increased when the Pn decreased after 6 days of storage. This result suggests that the decreased Pn is not solely a stomatal effect, as the effects on the chloroplasts contributed to this photosynthetic inhibition. Six days after transplanting, seedlings that were stored in the light or darkness for 2 or 4 days showed complete recovery of chloroplast ultrastructure, chlorophyll content, Fv/Fm, Gs and Pn. When the storage period increased to 6 days, the dark-stored seedlings had a significantly lower Fv/Fm and Pn than the light-stored and control seedlings 6 days after transplanting, which was mainly ascribed to incomplete recovery of chloroplast ultrastructure. Furthermore, the light-stored seedlings exhibited a significantly higher shoot dry weight during storage and a higher percentage dry weight increase after transplanting than the dark-stored seedlings. These effects were enhanced by prolonged storage (4 to 6 days). This study demonstrated that dim light during storage is beneficial for maintaining chloroplast ultrastructure as well as photosynthetic efficiency in watermelon seedlings, thus contributing to the rapid recovery of post-storage photosynthetic performance, which ensures the transplant quality

  8. The Maple reactor project

    International Nuclear Information System (INIS)

    Malkoske, G.R.; Labrie, J.-P.

    2003-01-01

    MDS Nordion supplies the majority of the world's reactor-produced medical isotopes. These isotopes are currently produced in the NRU reactor at AECL's Chalk River Laboratories (CRL). Medical isotopes and related technology are relied upon around the world to prevent, diagnose and treat disease. The NRU reactor, which has played a key role in supplying medical isotopes to date, has been in operation for over 40 years. Replacing this aging reactor has been a priority for MDS Nordion to assure the global nuclear medicine community that Canada will continue to be a dependable supplier of medical isotopes. MDS Nordion contracted AECL to construct two MAPLE reactors dedicated to the production of medical isotopes. The MDS Nordion Medical Isotope Reactor (MMIR) project started in September 1996. This paper describes the MAPLE reactors that AECL has built at its CRL site, and will operate for MDS Nordion. (author)

  9. Cavity size and copper root pruning affect production and establishment of container-grown longleaf pine seedlings

    Science.gov (United States)

    Marry Anne Sword Sayer; James D. Haywood; Shi-Jean Susana Sung

    2009-01-01

    With six container types, we tested the effects of cavity size (i.e., 60, 93, and 170 ml) and copper root pruning on the root system development of longleaf pine (Pinus palustris Mill.) seedlings grown in a greenhouse. We then evaluated root egress during a root growth potential test and assessed seedling morphology and root system development 1 year after planting in...

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

    Science.gov (United States)

    Simon, Judy; Li, Xiuyuan; Rennenberg, Heinz

    2014-01-01

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

  11. The Maple Products: An Outdoor Education Unit.

    Science.gov (United States)

    Yaple, Charles; And Others

    Designed to take advantage of the spring season, this resource packet on maple products centers upon a field lesson in harvesting and making maple syrup. The resources in this packet include: a narrative on the origins of maple sugar; an illustrated description of "old time maple sugarin'"; suggestions for pre-trip activities (history of…

  12. Consumer Preference for Graded Maple Syrup

    Science.gov (United States)

    Paul E. Sendak

    1978-01-01

    The three grades of maple syrup and a commercial table syrup containing artificial flavor and 3 percent pure maple syrup were evaluated by 1,018 women in four cities. The results indicate that differences in preference for flavor are related to how close the respondents are to a maple syrup-production region. Differences in preference among grades of pure maple syrup...

  13. Quantifying Efficacy and Limits of Unmanned Aerial Vehicle (UAV Technology for Weed Seedling Detection as Affected by Sensor Resolution

    Directory of Open Access Journals (Sweden)

    José M. Peña

    2015-03-01

    Full Text Available In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera, spatial (flight altitude and temporal (the date of the study resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2, when plants had 5–6 true leaves, had the highest weed detection accuracy (up to 91%. At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations.

  14. Quantifying efficacy and limits of unmanned aerial vehicle (UAV) technology for weed seedling detection as affected by sensor resolution.

    Science.gov (United States)

    Peña, José M; Torres-Sánchez, Jorge; Serrano-Pérez, Angélica; de Castro, Ana I; López-Granados, Francisca

    2015-03-06

    In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera), spatial (flight altitude) and temporal (the date of the study) resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2), when plants had 5-6 true leaves, had the highest weed detection accuracy (up to 91%). At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing) because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations.

  15. Growth, allocation and tissue chemistry of Picea abies seedlings affected by nutrient supply during the second growing season.

    Science.gov (United States)

    Kaakinen, Seija; Jolkkonen, Annika; Iivonen, Sari; Vapaavuori, Elina

    2004-06-01

    One-year-old Norway spruce (Picea abies (L.) Karst.) seedlings were grown hydroponically in a growth chamber to investigate the effects of low and high nutrient availability (LN; 0.25 mM N and HN; 2.50 mM N) on growth, biomass allocation and chemical composition of needles, stem and roots during the second growing season. Climatic conditions in the growth chamber simulated the mean growing season from May to early October in Flakaliden, northern Sweden. In the latter half of the growing season, biomass allocation changed in response to nutrient availability: increased root growth and decreased shoot growth led to higher root/shoot ratios in LN seedlings than in HN seedlings. At high nutrient availability, total biomass, especially stem biomass, increased, as did total nonstructural carbohydrate and nitrogen contents per seedling. Responses of stem chemistry to nutrient addition differed from those of adult trees of the same provenance. In HN seedlings, concentrations of alpha-cellulose, hemicellulose and lignin decreased in the secondary xylem. Our results illustrate the significance of retranslocation of stored nutrients to support new growth early in the season when root growth and nutrient uptake are still low. We conclude that nutrient availability alters allocation patterns, thereby influencing the success of 2-year-old Norway spruce seedlings at forest planting sites.

  16. The advanced MAPLE reactor concept

    International Nuclear Information System (INIS)

    Lidstone, R.F.; Lee, A.G.; Gillespie, G.E.; Smith, H.J.

    1989-01-01

    During the past several years, Atomic Energy of Canada Limited (AECL) has been developing the new MAPLE multipurpose reactor concept, which is capable of generating peak thermal neutron fluxes of up to 3 x 10 18 n/m 2 s in its heavy water reflector at a nominal thermal power level of 15MW. An assessment of the MAPLE-D 2 O reactor has shown that it could also be used as a high-flux neutron source. it could be developed to be used for several applications if a 12-site annular core is used. Thermal fluxes several times greater than in existing facilities would be available (author)

  17. Maturation of sugar maple seed

    Science.gov (United States)

    Clayton M., Jr. Carl; Albert G., Jr. Snow; Albert G. Snow

    1971-01-01

    The seeds of a sugar maple tree (Acer saccharum Marsh.) do not mature at the same time every year. And different trees mature their seeds at different times. So time of year is not a reliable measure of when seeds are ripe. Better criteria are needed. In recent studies we have found that moisture content and color are the best criteria for judging when sugar maple...

  18. Leaf age affects the responses of foliar injury and gas exchange to tropospheric ozone in Prunus serotina seedlings

    Science.gov (United States)

    Jianwei Zhang; Marcus Schaub; Jonathan A. Ferdinand; John M. Skelly; Kim C. Steiner; James E. Savage

    2010-01-01

    We investigated the effect of leaf age on the response of net photosynthesis (A), stomatal conductance (gwv), foliar injury, and leaf nitrogen concentration (NL) to tropospheric ozone (O3) on Prunus serotina seedlings grown in open-plots (AA) and open-top...

  19. Analysis of pure maple syrup consumers

    Science.gov (United States)

    Paul E. Sendak

    1974-01-01

    Virtually all of the pure maple syrup productim in the United States is in the northern states of Maine, Massachusetts, Michigan, New Hampshire, New York, Ohio, Pennsylvania, Vermont, and Wisconsin. Pure maple syrup users living in the maple production area and users living in other areas of the United States were asked a series of questions about their use of pure...

  20. The advanced MAPLE reactor concept

    International Nuclear Information System (INIS)

    Lidstone, R.F.; Lee, A.G.; Gillespie, G.E.; Smith, H.J.

    1989-01-01

    In Canada the need for advanced neutron sources has long been recognized. During the past several years Atomic Energy of Canada Limited (AECL) has been developing the new MAPLE multipurpose reactor concept. To date, the MAPLE program has focused on the development of a modest-cost multipurpose medium-flux neutron source to meet contemporary requirements for applied and basic research using neutron beams, for small-scale materials testing and analysis and for radioisotope production. The basic MAPLE concept incorporates a compact light-water cooled and moderated core within a heavy water primary reflector to generate strong neutron flux levels in a variety of irradiation facilities. In view of renewed Canadian interest in a high-flux neutron source, the MAPLE group has begun to explore advanced concepts based on AECL's experience with heavy water reactors. The overall objective is to define a high-flux facility that will support materials testing for advanced power reactors, new developments in extracted neutron-beam applications, and/or production of radioisotopes. The design target is to attain performance levels of HFR-Grenoble, HFBR, HFIR in a new heavy water-cooled, -moderated,-reflected reactor based on rodded LEU fuel. Physics, shielding, and thermohydraulic studies have been performed for the MAPLE heavy water reactor. 14 refs., 4 figs., 1 tab

  1. Seed Burial Depth and Soil Water Content Affect Seedling Emergence and Growth of Ulmus pumila var. sabulosa in the Horqin Sandy Land

    Directory of Open Access Journals (Sweden)

    Jiao Tang

    2016-01-01

    Full Text Available We investigated the effects of seed burial depth and soil water content on seedling emergence and growth of Ulmus pumila var. sabulosa (sandy elm, an important native tree species distributed over the European-Asian steppe. Experimental sand burial depths in the soil were 0.5, 1.0, 1.5, 2.0 and 2.5 cm, and soil water contents were 4%, 8%, 12% and 16% of field capacity. All two-way ANOVA (five sand burial depths and four soil water contents results showed that seed burial depths, soil water content and their interactions significantly affected all the studied plant variables. Most of the times, seedling emergence conditions were greater at the lower sand burial depths (less than 1.0 cm than at the higher (more than 1.0 cm seed burial depths, and at the lower water content (less than 12% than at the higher soil water content. However, high seed burial depths (more than 1.5 cm or low soil water content (less than 12% reduced seedling growth or change in the root/shoot biomass ratios. In conclusion, the most suitable range of sand burial was from 0.5 to 1.0 cm soil depth and soil water content was about 12%, respectively, for the processes of seedling emergence and growth. These findings indicate that seeds of the sandy elm should be kept at rather shallow soil depths, and water should be added up to 12% of soil capacity when conducting elm planting and management. Our findings could help to create a more appropriate sandy elm cultivation and understand sparse elm woodland recruitment failures in arid and semi-arid regions.

  2. Elevated atmospheric CO2 affected photosynthetic products in wheat seedlings and biological activity in rhizosphere soil under cadmium stress.

    Science.gov (United States)

    Jia, Xia; Liu, Tuo; Zhao, Yonghua; He, Yunhua; Yang, Mingyan

    2016-01-01

    The objective of this study was to investigate the effects of elevated CO2 (700 ± 23 μmol mol(-1)) on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated CO2 was associated with decreased quantities of reducing sugars, starch, and soluble amino acids, and with increased quantities of soluble sugars, total sugars, and soluble proteins in wheat seedlings under Cd stress. The contents of total soluble sugars, total free amino acids, total soluble phenolic acids, and total organic acids in the rhizosphere soil under Cd stress were improved by elevated CO2. Compared to Cd stress alone, the activity of amylase, phenol oxidase, urease, L-asparaginase, β-glucosidase, neutral phosphatase, and fluorescein diacetate increased under elevated CO2 in combination with Cd stress; only cellulase activity decreased. Bacterial abundance in rhizosphere soil was stimulated by elevated CO2 at low Cd concentrations (1.31-5.31 mg Cd kg(-1) dry soil). Actinomycetes, total microbial abundance, and fungi decreased under the combined conditions at 5.31-10.31 mg Cd kg(-1) dry soil. In conclusion, increased production of soluble sugars, total sugars, and proteins in wheat seedlings under elevated CO2 + Cd stress led to greater quantities of organic compounds in the rhizosphere soil relative to seedlings grown under Cd stress only. Elevated CO2 concentrations could moderate the effects of heavy metal pollution on enzyme activity and microorganism abundance in rhizosphere soils, thus improving soil fertility and the microecological rhizosphere environment of wheat under Cd stress.

  3. Spatial relationships between sugar maple (Acer saccharum Marsh), sugar maple decline, slope, aspect, and atmospheric deposition in northern Pennsylvania

    Science.gov (United States)

    Patrick Drohan; Susan Stout; Gary Peterson

    1999-01-01

    Sugar maple decline began to affect Allegheny Plateau forests in the early to mid-1980s. The forests of the region were exposed to several stresses In the period frorn 1985- 1996, including droughts during 1988, 1991, and 1995. Additionally, both native and exotic insects reached epidemic levels during this period (see, for example, Rhoads, 1993). Other documented...

  4. The advanced MAPLE reactor concept

    International Nuclear Information System (INIS)

    Lidstone, R.F.; Lee, A.G.; Gillespie, G.E.; Smith, H.J.

    1989-01-01

    High-flux neutron sources are continuing to be of interest both in Canada and internationally to support materials testing for advanced power reactors, new developments in extracted-neutron-beam applications, and commercial production of selected radioisotopes. The advanced MAPLE reactor concept has been developed to meet these needs. The advanced MAPLE reactor is a new tank-type D 2 O reactor that uses rodded low-enrichment uranium fuel in a compact annular core to generate peak thermal-neutron fluxes of 1 x 10 19 n·s -1 in a central irradiation rig with a thermal power output of 50 MW. Capital and incremental development costs are minimized by using MAPLE reactor technology to the greatest extent practicable

  5. Leaf age affects the responses of foliar injury and gas exchange to tropospheric ozone in Prunus serotina seedlings

    International Nuclear Information System (INIS)

    Zhang Jianwei; Schaub, Marcus; Ferdinand, Jonathan A.; Skelly, John M.; Steiner, Kim C.; Savage, James E.

    2010-01-01

    We investigated the effect of leaf age on the response of net photosynthesis (A), stomatal conductance (g wv ), foliar injury, and leaf nitrogen concentration (N L ) to tropospheric ozone (O 3 ) on Prunus serotina seedlings grown in open-plots (AA) and open-top chambers, supplied with either carbon-filtered or non-filtered air. We found significant variation in A, g wv , foliar injury, and N L (P 3 treatments. Seedlings in AA showed the highest A and g wv due to relatively low vapor pressure deficit (VPD). Older leaves showed significantly lower A, g wv , N L , and higher foliar injury (P wv , and foliar injury to O 3 . Both VPD and N L had a strong influence on leaf gas exchange. Foliar O 3 -induced injury appeared when cumulative O 3 uptake reached 8-12 mmol m -2 , depending on soil water availability. The mechanistic assessment of O 3 -induced injury is a valuable approach for a biologically relevant O 3 risk assessment for forest trees. - Ozone effects on symptom development and leaf gas exchange interacted with leaf age and N-content on black cherry seedlings.

  6. Foliar Nutrient Distribution Patterns in Sympatric Maple Species Reflect Contrasting Sensitivity to Excess Manganese.

    Science.gov (United States)

    Fernando, Denise R; Marshall, Alan T; Lynch, Jonathan P

    2016-01-01

    Sugar maple and red maple are closely-related co-occurring tree species significant to the North American forest biome. Plant abiotic stress effects including nutritional imbalance and manganese (Mn) toxicity are well documented within this system, and are implicated in enhanced susceptibility to biotic stresses such as insect attack. Both tree species are known to overaccumulate foliar manganese (Mn) when growing on unbuffered acidified soils, however, sugar maple is Mn-sensitive, while red maple is not. Currently there is no knowledge about the cellular sequestration of Mn and other nutrients in these two species. Here, electron-probe x-ray microanalysis was employed to examine cellular and sub-cellular deposition of excessively accumulated foliar Mn and other mineral nutrients in vivo. For both species, excess foliar Mn was deposited in symplastic cellular compartments. There were striking between-species differences in Mn, magnesium (Mg), sulphur (S) and calcium (Ca) distribution patterns. Unusually, Mn was highly co-localised with Mg in mesophyll cells of red maple only. The known sensitivity of sugar maple to excess Mn is likely linked to Mg deficiency in the leaf mesophyll. There was strong evidence that Mn toxicity in sugar maple is primarily a symplastic process. For each species, leaf-surface damage due to biotic stress including insect herbivory was compared between sites with acidified and non-acidified soils. Although it was greatest overall in red maple, there was no difference in biotic stress damage to red maple leaves between acidified and non-acidified soils. Sugar maple trees on buffered non-acidified soil were less damaged by biotic stress compared to those on unbuffered acidified soil, where they are also affected by Mn toxicity abiotic stress. This study concluded that foliar nutrient distribution in symplastic compartments is a determinant of Mn sensitivity, and that Mn stress hinders plant resistance to biotic stress.

  7. Effects of elevated ozone on CO2 uptake and leaf structure in sugar maple under two light environments

    International Nuclear Information System (INIS)

    Bäck, J.; Vanderklein, D.W.; Topa, M.A.

    1999-01-01

    The interactive effects of ozone and light on leaf structure, carbon dioxide uptake and short-term carbon allocation of sugar maple (Acer saccharum Marsh.) seedlings were examined using gas exchange measurements and 14 C-macroautoradiographic techniques. Two-year-old sugar maple seedlings were fumigated from budbreak for 5 months with ambient or 3 × ambient ozone in open-top chambers, receiving either 35% (high light) or 15% (low light) of full sunlight. Ozone accelerated leaf senescence, and reduced net photosynthesis, 14 CO 2 uptake and stomatal conductance, with the effects being most pronounced under low light. The proportion of intercellular space increased in leaves of seedlings grown under elevated ozone and low light, possibly enhancing the susceptibility of mesophyll cells to ozone by increasing the cumulative dose per mesophyll cell. Indeed, damage to spongy mesophyll cells in the elevated ozone × low light treatment was especially frequent. 14 C macroautoradioraphy revealed heterogeneous uptake of 14 CO 2 in well defined areole regions, suggesting patchy stomatal behaviour in all treatments. However, in seedlings grown under elevated ozone and low light, the highest 14 CO 2 uptake occurred along larger veins, while interveinal regions exhibited little or no uptake. Although visible symptoms of ozone injury were not apparent in these seedlings, the cellular damage, reduced photosynthetic rates and reduced whole-leaf chlorophyll levels corroborate the visual scaling of whole-plant senescence, suggesting that the ozone × low light treatment accelerated senescence or senescence-like injury in sugar maple. (author)

  8. Correlation of foliage and litter chemistry of sugar maple, Acer saccharum, as affected by elevated CO2 and varying N availability, and effects on decomposition

    Science.gov (United States)

    J. S. King; K. S. Pregitzer; D. R. Zak; M. E. Kubiske; W. E. Holmes

    2001-01-01

    Rising atmospheric carbon dioxide has the potential to alter leaf litter chemistry, potentially affecting decomposition and rates of carbon and nitrogen cycling in forest ecosystems. This study was conducted to determine whether growth under elevated atmospheric CO2 altered the quality and microbial decomposition of leaf litter of a widely...

  9. Drought and Heat Differentially Affect XTH Expression and XET Activity and Action in 3-Day-Old Seedlings of Durum Wheat Cultivars with Different Stress Susceptibility.

    Science.gov (United States)

    Iurlaro, Andrea; De Caroli, Monica; Sabella, Erika; De Pascali, Mariarosaria; Rampino, Patrizia; De Bellis, Luigi; Perrotta, Carla; Dalessandro, Giuseppe; Piro, Gabriella; Fry, Stephen C; Lenucci, Marcello S

    2016-01-01

    Heat and drought stress have emerged as major constraints for durum wheat production. In the Mediterranean area, their negative effect on crop productivity is expected to be exacerbated by the occurring climate change. Xyloglucan endotransglucosylase/hydrolases (XTHs) are chief enzymes in cell wall remodeling, whose relevance in cell expansion and morphogenesis suggests a central role in stress responses. In this work the potential role of XTHs in abiotic stress tolerance was investigated in durum wheat. The separate effects of dehydration and heat exposure on XTH expression and its endotransglucosylase (XET) in vitro activity and in vivo action have been monitored, up to 24 h, in the apical and sub-apical root regions and shoots excised from 3-day-old seedlings of durum wheat cultivars differing in stress susceptibility/tolerance. Dehydration and heat stress differentially influence the XTH expression profiles and the activity and action of XET in the wheat seedlings, depending on the degree of susceptibility/tolerance of the cultivars, the organ, the topological region of the root and, within the root, on the gradient of cell differentiation. The root apical region was the zone mainly affected by both treatments in all assayed cultivars, while no change in XET activity was observed at shoot level, irrespective of susceptibility/tolerance, confirming the pivotal role of the root in stress perception, signaling, and response. Conflicting effects were observed depending on stress type: dehydration evoked an overall increase, at least in the apical region of the root, of XET activity and action, while a significant inhibition was caused by heat treatment in most cultivars. The data suggest that differential changes in XET action in defined portions of the root of young durum wheat seedlings may have a role as a response to drought and heat stress, thus contributing to seedling survival and crop establishment. A thorough understanding of the mechanisms underlying

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

    Science.gov (United States)

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

    2018-01-01

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

  11. MAPLE research reactor beam-tube performance

    International Nuclear Information System (INIS)

    Lee, A.G.; Lidstone, R.F.; Gillespie, G.E.

    1989-05-01

    Atomic Energy of Canada Limited (AECL) has been developing the MAPLE (Multipurpose Applied Physics Lattice Experimental) reactor concept as a medium-flux neutron source to meet contemporary research reactor applications. This paper gives a brief description of the MAPLE reactor and presents some results of computer simulations used to analyze the neutronic performance. The computer simulations were performed to identify how the MAPLE reactor may be adapted to beam-tube applications such as neutron radiography

  12. PHYSIOLOGICAL AND FOLIAR INJURY RESPONSES OF PRUNUS SEROTINA, FRAXINUS AMERICANA, AND ACER RUBRUM SEEDLINGS TO VARYING SOIL MOISTURE AND OZONE. (R825244)

    Science.gov (United States)

    Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings wer...

  13. On Robot Modelling using Maple

    OpenAIRE

    Wallén, Johanna

    2007-01-01

    This report studies robot modelling by means of the computer algebra tool Maple. First coordinate systems are described, and the more general way with transformation matrices is chosen in the further work. The position kinematics of the robot are then described by homogeneous transformations. The Denavit-Hartenberg representation is used, which is a systematic way to develop the forward kinematics for rigid robots. The velocity kinematics is then described by the Jacobian. The industrial robo...

  14. Auxin-dependent microtubule responses and seedling development are affected in a rice mutant resistant to EPC

    International Nuclear Information System (INIS)

    Nick, P.; Yatou, O.; Furuya, M.; Lambert, A.M.

    1994-01-01

    Mutants in rice (Oryza sativa L. cv. japonica) were used to study the role of the cytoskeleton in signal-dependent morphogenesis. Mutants obtained by gamma ray irradiation were selected that failed to show inhibition of coleoptile elongation by the anti microtubular drug ethyl-N-phenylcarbamate (EPC). The mutation EPC-Resistant 31 (ER31), isolated from such a screen, caused lethality in putatively homozygous embryos. Heterozygotes exhibited drug resistance, impaired development of crown roots, and characteristic changes in the pattern of cell elongation: cell elongation was enhanced in mesocotyls and leaf sheaths, but inhibited in coleoptiles. The orientation of cortical microtubules changed correspondingly: for etiolated seedlings, compared with the wild-type, they were more transverse with respect to the long cell axis in mesocotyls and leaf sheaths, but more longitudinal in coleoptiles. In mutant coleoptiles, in contrast to wild-type, microtubules did not reorient in response to auxin, and their response to microtubule-eliminating and microtubule-stabilizing drugs was conspicuously reduced. In contrast, they responded normally to other stimuli such as gibberellins or red light. Auxin sensitivity as assayed by the dose-response for callus induction did not show any significant differences between wild-type and mutant. The mutant phenotype is interpreted in terms of an interrupted link between auxin-triggered signal transduction and microtubule reorientation. (author)

  15. Maple Sugar Harvesting/Wild Rice Harvesting.

    Science.gov (United States)

    Minneapolis Public Schools, MN.

    Comprised of two separate booklets, this resource unit assists elementary teachers in explaining how the Ojibwe people harvest maple sugar and wild rice. The first booklet explains the procedure of tapping the maple trees for sap, preparation for boiling the sap, and the three forms the sugar is made into (granulated, "molded," and…

  16. Maple Flooring - How Architects View it

    Science.gov (United States)

    Gary R. Lindell

    1971-01-01

    In a study of architects'' opinions of maple flooring versus vinyl asbestos tile for school gymnasuims, resiliency and durability were found to be important factors favoring maple whereas vinyl asbestos tile was felt to be less costly and more dimesionally stable.

  17. Sugar maple: its characteristics and potentials

    Science.gov (United States)

    Ralph D. Nyland

    1999-01-01

    Sugar maple dominates the northern hardwood forest, but grows over a broader geographic area. Conditions of soil and climate largely limit its distribution, and account for its less continuous cover along fringes of the range. Sugar maple regenerates readily following a wide range of overstory treatments. Success depends upon its status as advance regeneration,...

  18. Maple Explorations, Perfect Numbers, and Mersenne Primes

    Science.gov (United States)

    Ghusayni, B.

    2005-01-01

    Some examples from different areas of mathematics are explored to give a working knowledge of the computer algebra system Maple. Perfect numbers and Mersenne primes, which have fascinated people for a very long time and continue to do so, are studied using Maple and some questions are posed that still await answers.

  19. Developing the MAPLE materials test reactor concept

    International Nuclear Information System (INIS)

    Lee, A.G.; Lidstone, R.F.; Donnelly, J.V.

    1992-05-01

    MAPLE-MTR is a new multipurpose research facility being planned by AECL Research as a possible replacement for the 35-year-old NRU reactor. In developing the MAPLE-MTR concept, AECL is starting from the recent design and licensing experience with the MAPLE-X10 reactor. By starting from technology developed to support the MAPLE-X10 design and adapting it to produce a concept that satisfies the requirements of fuel channel materials testing and fuel irradiation programs, AECL expects to minimize the need for major advances in nuclear technology (e.g., fuel, heat transfer). Formulation of the MAPLE-MTR concept is at an early stage. This report describes the irradiation requirements of the research areas, how these needs are translated into design criteria for the project and elements of the preliminary design concept

  20. Not only size matters: achene morphology affects time of seedling emergence in three heterocarpic species of Anacyclus (Anthemideae, Asteraceae

    Directory of Open Access Journals (Sweden)

    Torices, Rubén

    2013-06-01

    Full Text Available The production of two or more distinct fruit types by an individual, i.e. heterocarpy, is considered as a mixed dispersal strategy in which a proportion of the offspring is able to colonize new sites, whilst others remain near the maternal location. Here, we aimed to explore the effects of achene morphology (winged vs. unwinged achenes and achene size –measured here as achene mass– on post-dispersal life-history traits (probability and time of seedling emergence in three heterocarpic Anacyclus species (Anthemideae, Asteraceae. Morphology, size and germination performance were studied in achenes from six populations of Anacyclus clavatus (Desf. Pers., A. homogamos (Maire Humphries, and A. valentinus L. Our results show that achene morphology and size were related to their position within the capitulum, such that outer, winged achenes were significantly heavier than the inner, unwinged ones. Additionally, winged achenes germinated faster than unwinged ones. This pattern may be related to the sequential achene time of release displayed by these species. Finally, our findings cast doubt on the role of wings as structures that favor dispersal by wind in these three species of Anacyclus.La producción de dos o más tipos de frutos diferentes por un mismo individuo, i.e. heterocarpia, es considerada como una estrategia mixta de dispersión en la que una parte de la descendencia es capaz de colonizar nuevos sitios, mientras que la otra permanece cerca de la planta madre. En este trabajo, nuestro objetivo fue explorar los efectos de la morfología del aquenio (aquenios alados vs. no alados y de su tamaño –medido aquí como masa del aquenio– en la etapa del ciclo de vida siguiente a la dispersión (probabilidad de germinación y tiempo de emergencia de las plántulas de tres especies heterocárpicas del género Anacyclus (Anthemideae, Asteraceae. Se estudió la morfología, el tamaño y la germinación en aquenios de seis poblaciones de Anacyclus

  1. Vine maple (Acer circinatum) clone growth and reproduction in managed and unmanaged coastal Oregon douglas-fir forests

    Science.gov (United States)

    O'Dea, Mary E.; Zasada, John C.; Tappeiner, John C.

    1995-01-01

    Vine maple (Acer circinatum Pursh.) clone development, expansion, and regeneration by seedling establishment were studied in 5-240 yr old managed and unmanaged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in coastal Oregon. Stem length, number of stems, and crown area were all significantly (P @10 m long and basal sprouts 1-2 m long; some stems had been pinned to the forest floor by fallen trees or branches and had layered. In stands >120 yr in age, clones were often quite complex, composed of several decumbent stems each of which connected the ramets of 1-10 new aerial stems. Vine maple clone expansion occurs by the layering of long aerial stems. Over 95% of the layered stems we observed had been pinned to the forest floor by fallen debris. Unsevered stems that we artificially pinned to the forest floor initiated roots within 1 yr. Thinning may favor clonal expansion because fallen slash from thinning often causes entire clones to layer, not just individual stems. Clonal vine maple seed production and seedling establishment occurred in all stages of stand development except dense, young stands following crown closure. There were more seedlings in thinned stands than in unthinned stands and in unburned clearcuts than in burned clearcuts.

  2. Competition for nitrogen between Fagus sylvatica and Acer pseudoplatanus seedlings depends on soil nitrogen availability

    Directory of Open Access Journals (Sweden)

    Xiuyuan eLi

    2015-04-01

    Full Text Available Competition for nitrogen (N, particularly in resource-limited habitats, might be avoided by different N acquisition strategies of plants. In our study, we investigated whether slow-growing European beech and fast-growing sycamore maple seedlings avoid competition for growth-limiting N by different N uptake patterns and the potential alteration by soil N availability in a microcosm experiment. We quantified growth and biomass indices, 15N uptake capacity and N pools in the fine roots. Overall, growth indices, N acquisition and N pools in the fine roots were influenced by species-specific competition depending on soil N availability. With interspecific competition, growth of sycamore maple reduced regardless of soil N supply, whereas beech only showed reduced growth when N was limited. Both species responded to interspecific competition by alteration of N pools in the fine roots; however, sycamore maple showed a stronger response compared to beech for almost all N pools in roots, except for structural N at low soil N availability. Beech generally preferred organic N acquisition while sycamore maple took up more inorganic N. Furthermore, with interspecific competition, beech had an enhanced organic N uptake capacity, while in sycamore maple inorganic N uptake capacity was impaired by the presence of beech. Although sycamore maple could tolerate the suboptimal conditions at the cost of reduced growth, our study indicates its reduced competitive ability for N compared to beech.

  3. Cadmium uptake by and translocation within rice (oryza sativa l.) seedlings as affected by iron plaque and Fe/sub 2/O/sub 3/

    International Nuclear Information System (INIS)

    Lai, Y.; Xu, B.O.; Mou, S.

    2012-01-01

    A hydroponics culture experiment was carried out to investigate the effect of iron plaque and/or Fe/sub 2/O/sub 3/ on Cadmium (Cd) uptake by and translocation within rice seedlings. Uniform rice seedlings grown in nutrient solution for two weeks were selected and transferred to nutrient solution containing ferrous iron (Fe/sup 2+/) (30 mg/L) for 24 h to induce the formation of iron plaque on the root surface. Then rice seedlings were exposed to different level of Cd (1.0 mg/L and 0.1 mg/L), and simultaneously Fe/sub 2/O/sub 3/ was added into hydroponic system for three days. At harvest Cd content in dithionite-citrate-bicarbonate (DCB) extracts, roots and shoots were determined. The results of this study showed that iron plaque could sequester more Cd on root surfaces of rice seedlings, however, Fe/sub 2/O/sub 3/ reduced Cd adsorbed on root surfaces. Both of iron plaque and/or Fe/sub 2/O/sub 3/ did not block Cd uptake by and translocation within rice seedlings. Although iron plaque could alleviate Cd toxicity to rice seedlings under low concentration of Cd (0.1 mg/L), the root tissue played more important role in reducing Cd translocation into shoot. And the long period experiment of hydroponic and soil culture was still needed to verify the potential effect of iron plaque and/or Fe/sub 2/O/sub 3/ on alleviating Cd toxicity to rice seedlings. (author)

  4. Contrasting nutritional acclimation of sugar maple (Acer saccharum Marsh. and red maple (Acer rubrum L. to increasing conifers and soil acidity as demonstrated by foliar nutrient balances

    Directory of Open Access Journals (Sweden)

    Alexandre Collin

    2016-07-01

    Full Text Available Sugar maple (Acer saccharum Marshall, SM is believed to be more sensitive to acidic and nutrient-poor soils associated with conifer-dominated stands than red maple (Acer rubrum L., RM. Greater foliar nutrient use efficiency (FNUE of RM is likely the cause for this difference. In the context of climate change, this greater FNUE could be key in favouring northward migration of RM over SM. We used the concept of foliar nutrient balances to study the nutrition of SM and RM seedlings along an increasing gradient in forest floor acidity conditioned by increasing proportions of conifers (pH values ranging from 4.39 under hardwoods, to 4.29 under mixed hardwood-conifer stands and 4.05 under conifer-dominated stands. Nutrients were subjected to isometric log-ratio (ilr transformation, which views the leaf as one closed system and considers interactions between nutrients. The ilr method eliminates numerical biases and weak statistical inferences based on raw or operationally’’ log-transformed data. We analyzed foliar nutrients of SM and RM seedlings and found that the [Ca,Mg,K|P,N] and [Ca,Mg|K] balances of SM seedlings were significantly different among soil acidity levels, whereas they did not vary for RM seedlings. For SM seedlings, these differences among soil acidity levels were due to a significant decrease in foliar Ca and Mg concentrations with increasing forest floor acidity. Similar differences in foliar balances were also found between healthy and declining SM stands estimated from literature values. Conversely, foliar balances of RM seedlings did not differ among soil acidity levels, even though untransformed foliar nutrient concentrations were significantly different. This result highlights the importance of using ilr transformation, since it provides more sensitive results than standard testing of untransformed nutrient concentrations. The lower nutrient requirements of RM and its greater capacity to maintain nutrient equilibrium are

  5. Sugar maple ecology and health: proceedings of an international symposium

    Science.gov (United States)

    Stephen B. Horsley; Robert P. Long; eds.

    1999-01-01

    Contains 28 papers and abstracts on sugar maple history and ecology; recent sugar maple declines; nutrient and belowground dynamics in northeastern forests; and interactions of forest health with biotic and abiotic stressors.

  6. Cotyledon persistence and seedling growth in fluted Pumpkin ...

    African Journals Online (AJOL)

    Photosynthetic activity of exposed cotyledons of Telfairia occidentalis during seed germination and the growth of seedlings with removed or attached cotyledons were investigated. The experiment investigated how early cotyledon removal affects seedling growth. Seedlings from seeds germinated in light and those ...

  7. Interactions between cadmium and other heavy metals in affecting the growth of lettuce (Lactuca sativa L. c. v. Webbs Wonderful) seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Lepp, N.W.

    1977-01-01

    Changes in root and shoot extension of lettuce seedlings in relation to single or dual applications of heavy metal ions have been studied. When cadmium, copper, lead or nickel are applied singly, at concentrations of 10 ..mu..g/litre, significant reductions in root and shoot growth of the seedlings are apparent. Dual ion applications of 10 ..mu..g/litre cadmium with 10 ..mu..g/litre of any of the other elements produce no significant synergistic reduction in seedling growth. The responses observed are either additive or antagonistic, depending upon the metal treatment. The results are discussed in terms of their possible significance to heavy metal effects on plant growth. 14 references, 1 figure.

  8. Abiotic factors affect the recruitment and biomass of perennial grass and evergreen shrub seedlings in denuded areas of Patagonian Monte rangelands.

    Science.gov (United States)

    Bosco, Tomás; Bertiller, Mónica Beatriz; Carrera, Analía Lorena

    2018-07-15

    Assessing the ability of key species to cope with environmental stresses in disturbed areas is an important issue for recovery of degraded arid ecosystem. Our objective was to evaluate the effect of soil moisture, exposure to UV radiation, and presence/absence of litter with different chemistry on soil N, recruitment and biomass of seedlings of perennial grass (Poa ligularis and Nassella tenuis) and evergreen shrub species (Atriplex lampa and Larrea divaricata) in denuded areas. We carried out a microcosm experiment with soil blocks (28 cm depth) sowed with seeds of the target species, subjected to different levels of litter type (perennial grass-evergreen shrub mixture, evergreen shrub mixture, and no litter), UV radiation (near ambient and reduced UV), and soil water (high: 15-25% and low 5-15%). Periodically, during 6 months, we assessed soil-N (total and inorganic) at two depths and species seedling recruitment at microcosms. Additionally, emerged seedlings of each species were transplanted to individual pots containing soil and subjected to the same previous factors during 12 months. Then, all plants were harvested and biomass assessed. Only inorganic soil-N at the upper soil varied among treatments increasing with the presence of evergreen shrub litter, exposure to ambient UV, and high soil water. Inorganic soil-N, promoted by near ambient UV and high soil water, had a positive effect on recruitment of perennial grasses and A. lampa. Both litter types promoted the recruitment of perennial grasses. Evergreen shrub litter and high soil water promoted the recruitment of L. divaricata. Seedling biomass of perennial grasses increased with high soil water and reduced UV. Ambient UV had positive or null effects on biomass of evergreen shrub seedlings. High soil water increased biomass of L. divaricata seedlings. We concluded that soil water appeared as the most limiting factor for seedling recruitment of all species whereas inorganic soil N limited the

  9. Calculus of One and More Variables with Maple

    Science.gov (United States)

    Samkova, Libuse

    2012-01-01

    This is a guide to using Maple in teaching fundamental calculus of one, two and three variables (limits, derivatives, integrals, etc.), also suitable for Maple beginners. It outlines one of the ways to effective use of computers in the teaching process. It scans advantages and disadvantages of using Maple in relation to students and teacher. The…

  10. The first use of N-carbamylglutamate in a patient with decompensated maple syrup urine disease

    NARCIS (Netherlands)

    Ucar, Sema Kalkan; Coker, Mahmut; Habif, Sara; Saz, Eylem Ulas; Karapinar, Bulent; Ucar, Hakan; Kitis, Omer; Duran, Marinus

    2009-01-01

    Maple syrup urine disease (MSUD) is a defect in the catabolism of the branched-chain amino acids; leucine, isoleucine, and valine. Affected patients may also develop hyperammonaemia of unknown etiology. This report describes a four-year-old girl with MSUD, who presented with decompensated

  11. Dual Mechanism of Brain Injury and Novel Treatment Strategy in Maple Syrup Urine Disease

    Science.gov (United States)

    Zinnanti, William J.; Lazovic, Jelena; Griffin, Kathleen; Skvorak, Kristen J.; Paul, Harbhajan S.; Homanics, Gregg E.; Bewley, Maria C.; Cheng, Keith C.; LaNoue, Kathryn F.; Flanagan, John M.

    2009-01-01

    Maple syrup urine disease (MSUD) is an inherited disorder of branched-chain amino acid metabolism presenting with life-threatening cerebral oedema and dysmyelination in affected individuals. Treatment requires life-long dietary restriction and monitoring of branched-chain amino acids to avoid brain injury. Despite careful management, children…

  12. The growth and uptake of Ga and In of rice (Oryza sative L.) seedlings as affected by Ga and In concentrations in hydroponic cultures.

    Science.gov (United States)

    Syu, Chien-Hui; Chien, Po-Hsuan; Huang, Chia-Chen; Jiang, Pei-Yu; Juang, Kai-Wei; Lee, Dar-Yuan

    2017-01-01

    Limited information is available on the effects of gallium (Ga) and indium (In) on the growth of paddy rice. The Ga and In are emerging contaminants and widely used in high-tech industries nowadays. Understanding the toxicity and accumulation of Ga and In by rice plants is important for reducing the effect on rice production and exposure risk to human by rice consumption. Therefore, this study investigates the effect of Ga and In on the growth of rice seedlings and examines the accumulation and distribution of those elements in plant tissues. Hydroponic cultures were conducted in phytotron glasshouse with controlled temperature and relative humidity conditions, and the rice seedlings were treated with different levels of Ga and In in the nutrient solutions. The growth index and the concentrations of Ga and In in roots and shoots of rice seedlings were measured after harvesting. A significant increase in growth index with increasing Ga concentrations in culture solutions (<10mgGaL -1 ) was observed. In addition, the uptake of N, K, Mg, Ca, Mn by rice plants was also enhanced by Ga. However, the growth inhibition were observed while the In concentrations higher than 0.08mgL -1 , and the nutrients accumulated in rice plants were also significant decreased after In treatments. Based on the dose-response curve, we observed that the EC 10 (effective concentration resulting in 10% growth inhibition) value for In treatment was 0.17mgL -1 . The results of plant analysis indicated that the roots were the dominant sink of Ga and In in rice seedlings, and it was also found that the capability of translocation of Ga from roots to shoots were higher than In. In addition, it was also found that the PT 10 (threshold concentration of phytotoxicity resulting in 10% growth retardation) values based on shoot height and total biomass for In were 15.4 and 10.6μgplant -1 , respectively. The beneficial effects on the plant growth of rice seedlings were found by the addition of Ga in

  13. Biosensor Applications of MAPLE Deposited Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2014-10-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique derived from Pulsed Laser Deposition (PLD for deposition of delicate (polymers, complex biological molecules, etc. materials in undamaged form. The main difference of MAPLE technique with respect to PLD is the target: it is a frozen solution or suspension of the (guest molecules to be deposited in a volatile substance (matrix. Since laser beam energy is mainly absorbed by the matrix, damages to the delicate guest molecules are avoided, or at least reduced. Lipase, an enzyme catalyzing reactions borne by triglycerides, has been used in biosensors for detection of β-hydroxyacid esters and triglycerides in blood serum. Enzymes immobilization on a substrate is therefore required. In this paper we show that it is possible, using MAPLE technique, to deposit lipase on a substrate, as shown by AFM observation, preserving its conformational structure, as shown by FTIR analysis.

  14. DEVELOPMENT OF MAPLE IN TRAINING HIGHER MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Volodymyr M. Mykhalevych

    2011-03-01

    Full Text Available The relevance of the material presented in this paper due to the need to develop and implement new information technologies in teaching higher mathematics with the use of systems of symbolic mathematics. Brief analysis of the Maple and Mathematica is given. The basic results of authors on working out of a training complex on higher mathematics are given. The complex was created in an environment of symbolic mathematics Maple. Procedure simulators, which give the whole process of model solutions of mathematical problems are a major element of the complex. The results of such procedures for typical problems from different sections of higher mathematics in accordance with the program for technical universities are represented. Questions the benefits and methods of using such programs, in particular those related to deficits of licensed copies of Maple was touched.

  15. Sugar maple growth in relation to nutrition and stress in the northeastern United States.

    Science.gov (United States)

    Long, Robert P; Horsley, Stephen B; Hallett, Richard A; Bailey, Scott W

    2009-09-01

    Sugar maple, Acer saccharum, decline disease is incited by multiple disturbance factors when imbalanced calcium (Ca), magnesium (Mg), and manganese (Mn) act as predisposing stressors. Our objective in this study was to determine whether factors affecting sugar maple health also affect growth as estimated by basal area increment (BAI). We used 76 northern hardwood stands in northern Pennsylvania, New York, Vermont, and New Hampshire, USA, and found that sugar maple growth was positively related to foliar concentrations of Ca and Mg and stand level estimates of sugar maple crown health during a high stress period from 1987 to 1996. Foliar nutrient threshold values for Ca, Mg, and Mn were used to analyze long-term BAI trends from 1937 to 1996. Significant (P maples sampled in the 1990s had decreased growth in the 1970s, 10-20 years in advance of the 1980s and 1990s decline episode in Pennsylvania. Even apparently healthy stands that had no defoliation, but had below-threshold amounts of Ca or Mg and above-threshold Mn (from foliage samples taken in the mid 1990s), had decreasing growth by the 1970s. Co-occurring black cherry, Prunus serotina, in a subset of the Pennsylvania and New York stands, showed opposite growth responses with greater growth in stands with below-threshold Ca and Mg compared with above-threshold stands. Sugar maple growing on sites with the highest concentrations of foliar Ca and Mg show a general increase in growth from 1937 to 1996 while other stands with lower Ca and Mg concentrations show a stable or decreasing growth trend. We conclude that acid deposition induced changes in soil nutrient status that crossed a threshold necessary to sustain sugar maple growth during the 1970s on some sites. While nutrition of these elements has not been considered in forest management decisions, our research shows species specific responses to Ca and Mg that may reduce health and growth of sugar maple or change species composition, if not addressed.

  16. Equine atypical myopathy caused by hypoglycin A intoxication associated with ingestion of sycamore maple tree seeds.

    Science.gov (United States)

    Żuraw, A; Dietert, K; Kühnel, S; Sander, J; Klopfleisch, R

    2016-07-01

    Evidence suggest there is a link between equine atypical myopathy (EAM) and ingestion of sycamore maple tree seeds. To further evaluate the hypothesis that the ingestion of hypoglycin A (HGA) containing sycamore maple tree seeds causes acquired multiple acyl-CoA dehydrogenase deficiency and might be associated with the clinical and pathological signs of EAM. Case report. Necropsy and histopathology, using hematoxylin and eosin and Sudan III stains, were performed on a 2.5-year-old mare that died following the development of clinical signs of progressive muscle stiffness and recumbency. Prior to death, the animal ingested sycamore maple tree seeds (Acer pseudoplatanus). Detection of metabolites in blood and urine obtained post mortem was performed by rapid ultra-performance liquid chromatography-tandem mass spectrometry. Data from this case were compared with 3 geldings with no clinical history of myopathy. Macroscopic examination revealed fragments of maple tree seeds in the stomach and severe myopathy of several muscle groups including Mm. intercostales, deltoidei and trapezii. Histologically, the affected muscles showed severe, acute rhabdomyolysis with extensive accumulation of finely dispersed fat droplets in the cytoplasm of degenerated skeletal muscle cells not present in controls. Urine and serum concentrations of several acyl carnitines and acyl glycines were increased, and both contained metabolites of HGA, a toxic amino acid present in sycamore maple tree seeds. The study supports the hypothesis that ingestion of HGA-containing maple tree seeds may cause EAM due to acquired multiple acyl-CoA dehydrogenase deficiency. © 2015 EVJ Ltd.

  17. MAPLE research reactor safety uncertainty assessment methodology

    International Nuclear Information System (INIS)

    Sills, H.E.; Duffey, R.B.; Andres, T.H.

    1999-01-01

    The MAPLE (multipurpose Applied Physics Lattice Experiment) reactor is a low pressure, low temperature, open-tank-in pool type research reactor that operates at a power level of 5 to 35 MW. MAPLE is designed for ease of operation, maintenance, and to meet today's most demanding requirements for safety and licensing. The emphasis is on the use of passive safety systems and environmentally qualified components. Key safety features include two independent and diverse shutdown systems, two parallel and independent cooling loops, fail safe operation, and a building design that incorporates the concepts of primary containment supported by secondary confinement

  18. Partial differential equations & boundary value problems with Maple

    CERN Document Server

    Articolo, George A

    2009-01-01

    Partial Differential Equations and Boundary Value Problems with Maple presents all of the material normally covered in a standard course on partial differential equations, while focusing on the natural union between this material and the powerful computational software, Maple. The Maple commands are so intuitive and easy to learn, students can learn what they need to know about the software in a matter of hours- an investment that provides substantial returns. Maple''s animation capabilities allow students and practitioners to see real-time displays of the solutions of partial differential equations.  Maple files can be found on the books website. Ancillary list: Maple files- http://www.elsevierdirect.com/companion.jsp?ISBN=9780123747327  Provides a quick overview of the software w/simple commands needed to get startedIncludes review material on linear algebra and Ordinary Differential equations, and their contribution in solving partial differential equationsIncorporates an early introduction to Sturm-L...

  19. Seedling root targets

    Science.gov (United States)

    Diane L. Haase

    2011-01-01

    Roots are critical to seedling performance after outplanting. Although root quality is not as quick and simple to measure as shoot quality, target root characteristics should be included in any seedling quality assessment program. This paper provides a brief review of root characteristics most commonly targeted for operational seedling production. These are: root mass...

  20. Automorphosis-like growth in etiolated pea seedlings is induced by the application of chemicals affecting perception of gravistimulation and its signal transduction

    Science.gov (United States)

    Miyamoto, Kensuke; Hoshino, Tomoki; Hitotsubashi, Reiko; Yamashita, Masamichi; Ueda, Junichi

    Both microgravity conditions in space and simulated microgravity using a 3-dimensional clinostat resulted in: (1) automorphosis of etiolated pea seedlings, (2) epicotyls bending ca. 45° from the vertical line to the direction away from cotyledons, (3) inhibition of hook formation and (4) alternation of growth direction of roots. These facts indicate that the growth and development of etiolated pea seedlings on earth is under the influence of gravistimulation. Lanthanum and gadolinium ions, blockers of stretch-activated mechanosensitive ion channels, induced automorphosis-like epicotyl bending. Cantharidin, an inhibitor of protein phosphatase, also phenocopied automorphosis-like growth. On the other hand, cytochalasin B, cytochalasin D and brefeldin A did not induce automorphological epicotyl bending and inhibition of hook formation, although these compounds strikingly inhibited elongation of etiolated pea epicotyls. These results strongly suggest that stretch-activated mechanosensitive ion channels are involved in the perception of signals of gravistimuli in plants, and they are transduced by protein phosphorylation and dephosphorylation cascades by changing levels of calcium ions. Possible mechanisms to induce automorphosis-like growth in relation to gravity signals in etiolated pea seedlings are discussed.

  1. MAPLE activities and applications in gas sensors

    Czech Academy of Sciences Publication Activity Database

    Jelínek, Miroslav; Remsa, Jan; Kocourek, Tomáš; Kubešová, B.; Schůrek, J.; Myslík, V.

    2011-01-01

    Roč. 105, č. 3 (2011), 643-649 ISSN 0947-8396 Institutional research plan: CEZ:AV0Z10100522 Keywords : MAPLE * gas sensors * biomedicine * thin films Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.630, year: 2011

  2. Applications of Maple To Algebraic Cryptography.

    Science.gov (United States)

    Sigmon, Neil P.

    1997-01-01

    Demonstrates the use of technology to enhance the appreciation of applications involving abstract algebra. The symbolic manipulator Maple can perform computations required for a linear cryptosystem. One major benefit of this process is that students can encipher and decipher messages using a linear cryptosystem without becoming confused and…

  3. Plastic Tubing and Maple Syrup Quality

    Science.gov (United States)

    Russell S. Walters; Harry W. Yawney

    1978-01-01

    Maple syrup made from sap collected using improperly or carelessly installed plastic pipelines varied more in color from day to day, and was more often darker in color, than sap collected from either the property installed pipeline or clean, frequently emptied galvanized buckets. Use of both properly installed tubing and buckets, following recommended procedures,...

  4. Building improved models of sugar maple mortality

    Science.gov (United States)

    Charles H. Perry; Patrick L. Zimmerman

    2012-01-01

    The decline of sugar maple (Acer saccharum Marsh.) in the northern United States is causing concern, and several studies have identified soil properties that are linked to the observation of dead/dying trees. Unfortunately, the sample of trees supporting these studies is purposive in nature; soil properties are assessed only on those plots where dead...

  5. Maple Syrup Disease: Diagnosis and Therapy

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-06-01

    Full Text Available Infants at high risk for maple syrup disease (MSD were identified by family history and molecular testing for the Y393N mutation of the E1a subunit of the branched chain a-ketoacid dehydrogenase in a study at Johns Hopkins University School of Medicine, Baltimore, MD.

  6. Interannual and spatial variability of maple syrup yield as related to climatic factors

    Science.gov (United States)

    Houle, Daniel

    2014-01-01

    Sugar maple syrup production is an important economic activity for eastern Canada and the northeastern United States. Since annual variations in syrup yield have been related to climate, there are concerns about the impacts of climatic change on the industry in the upcoming decades. Although the temporal variability of syrup yield has been studied for specific sites on different time scales or for large regions, a model capable of accounting for both temporal and regional differences in yield is still lacking. In the present study, we studied the factors responsible for interregional and interannual variability in maple syrup yield over the 2001–2012 period, by combining the data from 8 Quebec regions (Canada) and 10 U.S. states. The resulting model explained 44.5% of the variability in yield. It includes the effect of climatic conditions that precede the sapflow season (variables from the previous growing season and winter), the effect of climatic conditions during the current sapflow season, and terms accounting for intercountry and temporal variability. Optimal conditions for maple syrup production appear to be spatially restricted by less favourable climate conditions occurring during the growing season in the north, and in the south, by the warmer winter and earlier spring conditions. This suggests that climate change may favor maple syrup production northwards, while southern regions are more likely to be negatively affected by adverse spring conditions. PMID:24949244

  7. Morphometric characteristics of sycamore maple (Acer pseudoplatanus L. fruits in Novi Sad urban populations

    Directory of Open Access Journals (Sweden)

    Kostić Saša

    2017-01-01

    Full Text Available This paper shows the results of the analysis of the fruit morphometric characteristics of 29 trees of sycamore maple (Acer pseudoplatanus L. and red - leaf sycamore maple (Acer pseudoplatanus ‘Аtropurpureum’ Späth. in Novi Sad area. Based on the test trees, it can be concluded that the analyzed secondary population of sycamore maple has a high level of intra - populations variability, based on different degrees of variability of measured parameters and statistically significant differences of all analyzed parameters within the analysed genotypes. The results indicate that there are certain differences between fruit of sycamore maple and its red - leaf variety. Given that there is no statistically significant difference between sites and different urban spaces, it can be concluded that stress factors caused by a high degree of urbanity do not affect the morphometric characteristics of fruits in the analyzed test trees. Testing the symmetry of fruits indicates a high level of genetic variability within the analyzed population.

  8. Thin films growth parameters in MAPLE; application to fibrinogen

    International Nuclear Information System (INIS)

    Jelinek, M; Cristescu, R; Kocourek, T; Vorlicek, V; Remsa, J; Stamatin, L; Mihaiescu, D; Stamatin, I; Mihailescu, I N; Chrisey, D B

    2007-01-01

    Increasingly requirements on the thin film quality of functionalized materials are efficiently met by a novel laser processing technique - Matrix Assisted Pulsed Laser Evaporation (MAPLE). Examples of deposition conditions and main features characteristic to film growth rate of MAPLE-fabricated organic materials are summarized. MAPLE experimental results are compared with ones corresponding to the classical Pulsed Laser Deposition (PLD). In particular, the results of investigation of MAPLE-deposited fibrinogen blood protein thin films using a KrF* excimer laser and characterized by FTIR and Raman spectrometry are reported

  9. Maple prepared organic heterostructures for photovoltaic applications

    Science.gov (United States)

    Stanculescu, A.; Socol, M.; Socol, G.; Mihailescu, I. N.; Girtan, M.; Stanculescu, F.

    2011-09-01

    In this study, we present the deposition of ZnPc, Alq3, and PTCDA thin films using Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. We also report the realisation of multilayer structures, made by the successive application of MAPLE. The films have been characterized by spectroscopic (UV-VIS and Photoluminescence) and microscopic (SEM and AFM) methods, and the effect of different deposition conditions such as fluence, number of pulses, and target concentration on the properties has been analysed. This paper also presents some investigations on the electrical conduction in sandwich type structures ITO or Si/organic layer/Au or Cu and ITO/double organic layer/Cu, emphasising the dominant effect of the height of the energetic barriers at the inorganic/organic and organic/organic interfaces.

  10. Geometry of curves and surfaces with Maple

    CERN Document Server

    Rovenski, Vladimir

    2000-01-01

    This concise text on geometry with computer modeling presents some elementary methods for analytical modeling and visualization of curves and surfaces. The author systematically examines such powerful tools as 2-D and 3-D animation of geometric images, transformations, shadows, and colors, and then further studies more complex problems in differential geometry. Well-illustrated with more than 350 figures---reproducible using Maple programs in the book---the work is devoted to three main areas: curves, surfaces, and polyhedra. Pedagogical benefits can be found in the large number of Maple programs, some of which are analogous to C++ programs, including those for splines and fractals. To avoid tedious typing, readers will be able to download many of the programs from the Birkhauser web site. Aimed at a broad audience of students, instructors of mathematics, computer scientists, and engineers who have knowledge of analytical geometry, i.e., method of coordinates, this text will be an excellent classroom resource...

  11. Maple prepared organic heterostructures for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Stanculescu, A.; Socol, M. [National Institute of Materials Physics, 105 bis Atomistilor Street, P.O. Box MG-7, Bucharest-Magurele (Romania); Socol, G.; Mihailescu, I.N. [Plasma and Radiation Physics, National Institute for Laser, P.O. Box MG-36, Bucharest-Magurele (Romania); Girtan, M. [Universite d' Angers, Laboratoire de Photonique d' Angers, Angers (France); Stanculescu, F. [University of Bucharest, Faculty of Physics, Str. Atomistilor nr. 405, P.O. Box MG-11, Bucharest-Magurele (Romania)

    2011-09-15

    In this study, we present the deposition of ZnPc, Alq3, and PTCDA thin films using Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. We also report the realisation of multilayer structures, made by the successive application of MAPLE. The films have been characterized by spectroscopic (UV-VIS and Photoluminescence) and microscopic (SEM and AFM) methods, and the effect of different deposition conditions such as fluence, number of pulses, and target concentration on the properties has been analysed. This paper also presents some investigations on the electrical conduction in sandwich type structures ITO or Si/organic layer/Au or Cu and ITO/double organic layer/Cu, emphasising the dominant effect of the height of the energetic barriers at the inorganic/organic and organic/organic interfaces. (orig.)

  12. Eastern Redcedar Seedling Assessment

    Data.gov (United States)

    U.S. Environmental Protection Agency — Eastern redcedar tree seedling growth in response to various soil, nitrogen, and photosynthetic radiation characteristics. This dataset is associated with the...

  13. Phenylbutyrate therapy for maple syrup urine disease

    OpenAIRE

    Brunetti-Pierri, Nicola; Lanpher, Brendan; Erez, Ayelet; Ananieva, Elitsa A.; Islam, Mohammad; Marini, Juan C.; Sun, Qin; Yu, Chunli; Hegde, Madhuri; Li, Jun; Wynn, R. Max; Chuang, David T.; Hutson, Susan; Lee, Brendan

    2010-01-01

    Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate in urea cycle disorder patients has been associated with a selective reduction in branched-chain amino acids (BCAA) in spite of adequate dietary protein intake. Based on this clinical observation, we investigated the potential of phenylbutyrate treatment to lower BCAA and their corresponding α-keto acids (BCKA) in patients with classic and variant late-onset forms of maple syrup urine disease (MSUD). We also performed in vitr...

  14. Licensing of MAPLE reactors in Canada

    International Nuclear Information System (INIS)

    Lee, A.G.; Labrie, J.P.; Langman, V.J.

    1999-01-01

    Full text: The Operating Licence for a MAPLE reactor (i.e., a 10 MW(th), pool-type reactor), has been approved by the Atomic Energy Control Board (AECB) on August 16th, 1999. This Operating Licence has been obtained within three years of the initiation of the MDS Nordion Medical Isotopes Reactor (MMIR) project, which entails the design, construction and commissioning of two 10 MW MAPLE reactors at AECL's Chalk River Laboratories. The scope and nature of the information required by the AECB, the licensing process and highlights of the events which led to successfully obtaining the Operating Licence for the MAPLE reactor are discussed. These discussions address all phases of the licensing process (i.e., the environmental assessment in support of siting, the Preliminary Safety Analysis Report, PSAR, in support of design, procurement and construction, the Final Safety Analysis Report, FSAR, in support of commissioning and operations, and the development of suitable quality assurance subprograms for each phase). An overview of some of the unique technical aspects associated with the MAPLE reactors, and how they have been addressed during the licensing process are also provided (e.g., applying CSA N285.0, General Requirements for Pressure-Retaining Systems and Components in CANDU Nuclear Power Plants, to a small, low pressure, low temperature research reactor, confirmation of the performance of the driver fuel via laboratory and/or in-reactor testing, validation of the computer codes used to perform the safety analyses, critical parameter uncertainty assessment, full scale hydraulic testing of the performance of the design, fuel handling, human factors validation, operator training and certification). (author)

  15. A cost analysis: processing maple syrup products

    Science.gov (United States)

    Neil K. Huyler; Lawrence D. Garrett

    1979-01-01

    A cost analysis of processing maple sap to syrup for three fuel types, oil-, wood-, and LP gas-fired evaporators, indicates that: (1) fuel, capital, and labor are the major cost components of processing sap to syrup; (2) wood-fired evaporators show a slight cost advantage over oil- and LP gas-fired evaporators; however, as the cost of wood approaches $50 per cord, wood...

  16. Frozen Microemulsions for MAPLE Immobilization of Lipase

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2017-12-01

    Full Text Available Candida rugosa lipase (CRL was deposited by matrix assisted pulsed laser evaporation (MAPLE in order to immobilize the enzyme with a preserved native conformation, which ensures its catalytic functionality. For this purpose, the composition of the MAPLE target was optimized by adding the oil phase pentane to a water solution of the amino acid 3-(3,4-dihydroxyphenyl-2-methyl-l-alanine (m-DOPA, giving a target formed by a frozen water-lipase-pentane microemulsion. Fourier transform infrared (FTIR spectroscopy and atomic force microscopy (AFM were used to investigate the structure of MAPLE deposited lipase films. FTIR deconvolution of amide I band indicated a reduction of unfolding and aggregation, i.e., a better preserved lipase secondary structure in the sample deposited from the frozen microemulsion target. AFM images highlighted the absence of big aggregates on the surface of the sample. The functionality of the immobilized enzyme to promote transesterification was determined by thin layer chromatography, resulting in a modified specificity.

  17. Dynamical systems with applications using Maple

    CERN Document Server

    Lynch, Stephen

    2001-01-01

    "The text treats a remarkable spectrum of topics and has a little for everyone. It can serve as an introduction to many of the topics of dynamical systems, and will help even the most jaded reader, such as this reviewer, enjoy some of the interactive aspects of studying dynamics using Maple." —UK Nonlinear News (Review of First Edition) "The book will be useful for all kinds of dynamical systems courses…. [It] shows the power of using a computer algebra program to study dynamical systems, and, by giving so many worked examples, provides ample opportunity for experiments. … [It] is well written and a pleasure to read, which is helped by its attention to historical background." —Mathematical Reviews (Review of First Edition) Since the first edition of this book was published in 2001, Maple™ has evolved from Maple V into Maple 13. Accordingly, this new edition has been thoroughly updated and expanded to include more applications, examples, and exercises, all with solutions; two new chapters on neural n...

  18. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  19. Genetic consequences of selection cutting on sugar maple (Acer saccharum Marshall).

    Science.gov (United States)

    Graignic, Noémie; Tremblay, Francine; Bergeron, Yves

    2016-07-01

    Selection cutting is a treatment that emulates tree-by-tree replacement for forests with uneven-age structures. It creates small openings in large areas and often generates a more homogenous forest structure (fewer large leaving trees and defective trees) that differs from old-growth forest. In this study, we evaluated whether this type of harvesting has an impact on genetic diversity of sugar maple (Acer saccharum Marshall). Genetic diversity among seedlings, saplings, and mature trees was compared between selection cut and old-growth forest stands in Québec, Canada. We found higher observed heterozygosity and a lower inbreeding coefficient in mature trees than in younger regeneration cohorts of both forest types. We detected a recent bottleneck in all stands undergoing selection cutting. Other genetic indices of diversity (allelic richness, observed and expected heterozygosity, and rare alleles) were similar between forest types. We concluded that the effect of selection cutting on the genetic diversity of sugar maple was recent and no evidence of genetic erosion was detectable in Québec stands after one harvest. However, the cumulative effect of recurring applications of selection cutting in bottlenecked stands could lead to fixation of deleterious alleles, and this highlights the need for adopting better forest management practices.

  20. Maple sugaring with vacuum pumping during the fall season

    Science.gov (United States)

    H. Clay Smith; Alan G., Jr. Snow

    1971-01-01

    Vacuum pumping of sugar maple trees during the late fall and early winter months is not advisable in northern Vermont. However, fall pumping may be profitable in other areas of the sugar maple range. It is recommended that the weather pattern in a given locale be observed; and if conditions are favorable, vacuum pumping should be tried on a small scale before...

  1. Yield and ultrasonic modulus of elasticity of red maple veneer

    Science.gov (United States)

    Robert J. Ross; Steven Verhey; John R. Erickson; John W. Forsman; Brian K. Brashaw; Crystal L. Pilon; Xiping Wang

    2004-01-01

    The purpose of the study was to assess the potential for using red maple sawlogs to manufacture laminated veneer lumber (LVL). The primary objective was to determine the yield of ultrasonically graded veneer from red maple logs. A sample of 48 logs was obtained from six Eastern and Lake States in the United States. The logs were visually graded and shipped to a plywood...

  2. HOW to Identify and Control Sugar Maple Borer

    Science.gov (United States)

    William H. Hoffard; Philip T. Marshall

    1978-01-01

    The sugar maple borer, Glycobius speciosus (Say), a long-horned wood boring beetle, is a common pest of sugar maple (the only known host) throughout the range of the tree. Although borer-caused mortality is rare, infestations lead to value loss through lumber defect caused by larval galleries, discoloration, decay, and twisted grain.

  3. Monitoring the Health of Sugar Maple, "Acer Saccharum"

    Science.gov (United States)

    Carlson, Martha

    2013-01-01

    The sugar maple, "Acer saccharum," is projected to decline and die in 88 to 100 percent of its current range in the United States. An iconic symbol of the northeastern temperate forest and a dominant species in this forest, the sugar maple is identified as the most sensitive tree in its ecosystem to rising temperatures and a warming…

  4. A ten-year regional assessment of sugar maple mortality

    Science.gov (United States)

    Douglas C. Allen; Andrew W. Molloy; Robert R. Cooke; Bruce A. Pendrel

    1999-01-01

    The North American Maple Project (NAMP) monitored annual sugar maple mortality from 1988 through 1997 in Maine, Massachusetts, New Brunswick/Nova Scotia, New Hampshire, New York. Ontario, Quebec, Vermont, and Wisconsin. Annual mortality in Minnesota, Ohio and Pennsylvania was evaluated for 1992 through 1997. When data from the dominant/codominant and intermediate/...

  5. Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup.

    Science.gov (United States)

    Sun, Jiadong; Ma, Hang; Seeram, Navindra P; Rowley, David C

    2016-09-28

    Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

  6. Carbon Nanotubes Filled with Different Ferromagnetic Alloys Affect the Growth and Development of Rice Seedlings by Changing the C:N Ratio and Plant Hormones Concentrations.

    Science.gov (United States)

    Hao, Yi; Yu, Feifan; Lv, Ruitao; Ma, Chuanxin; Zhang, Zetian; Rui, Yukui; Liu, Liming; Cao, Weidong; Xing, Baoshan

    2016-01-01

    The aim of this study was to investigate the phytotoxicity of thin-walled carbon nanotubes (CNTs) to rice (Oryza sativa L.) seedlings. Three different CNTs, including hollow multi-walled carbon nanotubes (MWCNTs), Fe-filled carbon nanotubes (Fe-CNTs), and Fe-Co-filled carbon nanotubes (FeCo-CNTs), were evaluated. The CNTs significantly inhibited rice growth by decreasing the concentrations of endogenous plant hormones. The carbon to nitrogen ratio (C:N ratio) significantly increased in rice roots after treatments with CNTs, and all three types of CNTs had the same effects on the C:N ratio. Interestingly, the increase in the C:N ratio in roots was largely because of decreased N content, indicating that the CNTs significantly decreased N assimilation. Analyses of the Fe and Co contents in plant tissues, transmission electron microscope (TEM) observations and energy dispersive X-ray spectroscopy (EDS) analysis proved that the CNTs could penetrate the cell wall and the cell membrane, and then enter the root cells. According to the author's knowledge, this is the first time to study the relationship between carbon nanotubes and carbon nitrogen ratio and plant hormones.

  7. Elevated ozone negatively affects photosynthesis of current-year leaves but not previous-year leaves in evergreen Cyclobalanopsis glauca seedlings

    International Nuclear Information System (INIS)

    Zhang, Weiwei; Feng, Zhaozhong; Wang, Xiaoke; Niu, Junfeng

    2014-01-01

    To assess the effects of leaf age/layer on the response of photosynthesis to chronic ozone (O 3 ), Cyclobalanopsis glauca seedlings, a dominant evergreen broadleaf tree species in sub-tropical regions, were exposed to either ambient air (AA) or elevated O 3 (AA + 60 ppb O 3 , E-O 3 ) for two growing seasons in open-top chambers. Chlorophyll content, gas exchange and chlorophyll a fluorescence were investigated three times throughout the 2nd year of O 3 exposure. Results indicated that E-O 3 decreased photosynthetic parameters, particularly light-saturated photosynthesis rate, stomatal conductance and effective quantum yield of PSII photochemistry of current-year leaves but not previous-year leaves. Stomatal conductance of plants grown under ambient conditions partially contributed to the different response to E-O 3 between leaf layers. Light radiation or other physiological and biochemical processes closely related to photosynthesis might play important roles. All suggested that leaf ages or layers should be considered when assessing O 3 risk on evergreen woody species. -- Highlights: • Response of evergreen Cyclobalanopsis glauca to O 3 was investigated. • Elevated O 3 significantly reduced photosynthesis of current-year leaves. • Previous-year leaves showed little response to O 3 . • Stomatal conductance contributes to the response difference to O 3 among leaf ages. -- Impacts of elevated O 3 on photosynthesis of evergreen woody species depend on leaf ages

  8. Solar ultraviolet-B radiation affects seedling emergence, DNA integrity, plant morphology, growth rate, and attractiveness to herbivore insects in Datura ferox

    International Nuclear Information System (INIS)

    Ballare, C.L.; Scopel, A.L.; Stapleton, A.E.

    1996-01-01

    To study functional relationships between the effects of solar ultraviolet-B radiation (UV0B) on different aspects of the physiology of a wild plant, we carried out exclusion experiments in the field with the summer annual Datura ferrox L. Solar UV-B incident over Buenos Aires reduced daytime seedling emergence, inhibited stem elongation and leaf expansion, and tended to reduce biomass accumulation during early growth. However, UV-B had no effect on calculated net assimilation rate. Using a monoclonal antibody specific to the cyclobutane-pyrimidine dimer (CPD), we found that plants receiving full sunlight had more CPDs per unit of DNA than plants shielded from solar UV-B, but the positive correlation between UV-B and CPD burden tended to level off at high (near solar) UV-B levels. At our field site, Datura plants were consumed by leaf beetles (Coleoptera), and the proportion of plants attacked by insects declined with the amount of UV-B received during growth. Field experiments showed that plant exposure to solar UV-B reduced the likelihood of leaf beetle attack by one-half. Our results highlight the complexities associated with scaling plant responses to solar UV-B, because they show: (a) a lack of correspondence between UV-B effects on net assimilation rate and whole-plant growth rate, (b) nonlinear UV-B dose-response curves, and (c) UV-B effects of plant attractiveness to natural herbivores. 56 refs., 7 figs

  9. MAPLE-X10 reactor safety assessment

    International Nuclear Information System (INIS)

    Cotnam, K.D.; Lounsbury, R.I.; Gillespie, G.E.

    1990-01-01

    This paper reports on the safety assessment of the 10 MW MAPLE-X10 reactor which has involved a substantial component of PSA analysis to supplement deterministic analysis. Initiating events are identified through the use of a master logic diagram. The events are then examined through event sequence diagrams, at the concept design stage, followed by a set of reliability analyses that are coordinated with the event sequence diagrams. Improvements identified through the reliability analyses are incorporated into the design to ensure that safety objectives are attained

  10. Rice seedling and plant development as affected by increasing rates of penoxsulam under controlled environments Desenvolvimento de plântulas e plantas adultas de arroz em função de doses crescentes de penoxsulam em ambiente controlado

    Directory of Open Access Journals (Sweden)

    G. Concenço

    2006-01-01

    Full Text Available Rice is a major staple in many countries. Weed control is one of the factors limiting higher rice yield. ALS (acetolactate synthase-inhibiting herbicides are desirable weed control herbicides because of their high efficacy, low toxicity to mammalians, and low rates used. An important herbicide characteristic is high selectivity to the crop, since it facilitates fast crop establishment and greater crop advantage over the weeds. The objectives of this work were to study the effects of increasing rates of the ALS-inhibiting herbicide penoxsulam on seed integrity and germination, and seedling and plant development of rice cv. BRS Pelota under controlled laboratory and greenhouse conditions. The results showed that penoxsulam affected rice germination and seedling and plant growth at rates above 54 g a.i. ha-1, and that penoxsulam is safe for rice seedling development at the currently recommended rates.O arroz é componente importante da dieta humana em vários países. Entre os fatores que limitam o aumento na sua produtividade está o controle de plantas daninhas. Os herbicidas inibidores da ALS (acetolactato sintase são preferidos em razão da alta eficiência no controle de plantas daninhas, da baixa toxicidade aos mamíferos e das baixas doses utilizadas. Uma característica importante que um herbicida deve possuir é a alta seletividade à cultura, pois ela implica estabelecimento mais rápido, com vantagem competitiva sobre as plantas daninhas. O objetivo deste trabalho foi estudar os efeitos do herbicida inibidor da ALS penoxsulam em doses crescentes sobre a integridade e germinação das sementes, bem como sobre o desenvolvimento inicial das plântulas e da planta adulta do cultivar BRS Pelota, sob condições de ambiente controlado (laboratório e casa de vegetação. Os resultados mostraram que o penoxsulam afetou a germinação e o crescimento de plântulas e plantas adultas nas doses acima de 54 g i.a. ha-1 e que ele é seguro para o

  11. Rapid root extension during water pulses enhances establishment of shrub seedlings in the Atacama Desert

    NARCIS (Netherlands)

    Leon, M.F.; Squeo, F.A.; Gutierrez, J.R.; Holmgren, M.

    2011-01-01

    Questions: (1) What is the water threshold for shrub seedling establishment in arid scrubland? (2) How do seedling root growth morphological traits affect the water threshold required for seedling establishment? Location: Arid scrubland, Atacama Desert, north-central Chile. Methods: We conducted a

  12. Characterizing Betula litwinowii seedling microsites at the alpine-treeline ecotone, central Greater Caucasus Mountains, Georgia

    Science.gov (United States)

    Nicole M Hughes; Daniel M. Johnson; Maia Akhalkatsi; Otar Abdaladze

    2009-01-01

    Seedling establishment is an important factor dictating the altitudinal limits of treeline species. Factors that affect seedling mortality and survival, however, have yet to be fully characterized, especially for deciduous treeline species. Here we describe microsite characteristics of successfully established Betula litwinowii seedlings at the...

  13. The nuclear design of the MAPLE-X10 reactor

    International Nuclear Information System (INIS)

    Heeds, W.; Lebenhaft, J.R.; Lee, A.G.; Carlson, P.A.; McIlvain, H.; Lidstone, R.F.

    1995-01-01

    AECL is currently building the 10-MW MAPLE-X10 reactor at the Chalk River Laboratories to operate as a dedicated producer of commercial-scale quantities of key medical and industrial radioisotopes and as a demonstration of the MAPLE reactor design. In support of the safety and licensing analyses, static physics calculations have been performed to determine the neutronic performance and safety characteristics of the MAPLE-X10 reactor. This report summarizes results from the static physics calculations for several core conditions prior to commencing radioisotope production. (author)

  14. Simulated root dynamics of a 160-year-old sugar maple (Acer saccharum Marsh.) tree with and without ozone exposure using the TREGRO model.

    Science.gov (United States)

    Retzlaff, W. A.; Weinstein, D. A.; Laurence, J. A.; Gollands, B.

    1996-01-01

    Because of difficulties in directly assessing root responses of mature forest trees exposed to atmospheric pollutants, we have used the model TREGRO to analyze the effects of a 3- and a 10-year exposure to ozone (O(3)) on root dynamics of a simulated 160-year-old sugar maple (Acer saccharum Marsh.) tree. We used existing phenological, allometric, and growth data to parameterize TREGRO to produce a simulated 160-year-old tree. Simulations were based on literature values for sugar maple fine root production and senescence and the photosynthetic responses of sugar maple seedlings exposed to O(3) in open-top chambers. In the simulated 3-year exposure to O(3), 2 x ambient atmospheric O(3) concentrations reduced net carbon (C) gain of the 160-year-old tree. This reduction occurred in the C storage pools (total nonstructural carbohydrate, TNC), with most of the reduction occurring in coarse (woody) roots. Total fine root production and senescence were unaffected by the simulated 3-year exposure to O(3). However, extending the simulated O(3) exposure period to 10 years depleted the TNC pools of the coarse roots and reduced total fine root production. Similar reductions in TNC pools have been observed in forest-grown sugar maple trees exhibiting symptoms of stress. We conclude that modeling can aid in evaluating the belowground response of mature forest trees to atmospheric pollution stress and could indicate the potential for gradual deterioration of tree health under conditions of long-term stress, a situation similar to that underlying the decline of sugar maple trees.

  15. Effects of graphene on seed germination and seedling growth

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ming; Gao, Bin, E-mail: bg55@ufl.edu [University of Florida, Department of Agricultural and Biological Engineering (United States); Chen, Jianjun [University of Florida, Department of Environmental Horticulture and Mid-Florida Research & Education Center (United States); Li, Yuncong [University of Florida, Soil and Water Science Department Tropical Research & Education Center (United States)

    2015-02-15

    The environmental impact of graphene has recently attracted great attention. In this work, we show that graphene at a low concentration affected tomato seed germination and seedling growth. Graphene-treated seeds germinated much faster than control seeds. Analytical results indicated that graphene penetrated seed husks. The penetration might break the husks to facilitate water uptake, resulting in faster germination and higher germination rates. At the stage of seedling growth, graphene was also able to penetrate root tip cells. Seedlings germinated from graphene-treated seeds had slightly lower biomass accumulation than the control, but exhibited significantly longer stems and roots than the control, which suggests that graphene, in contrast with other nanoparticles, had different effects on seedling growth. Taken together, our results imply that graphene played complicated roles in affecting the initial stage of seed germination and subsequent seedling growth.

  16. Genotype X Fertility Interactions in Seedling Sweetgum

    Science.gov (United States)

    Scott X. Chang; Daniel J. Robison

    2002-01-01

    Genotype x fertility interactions may affect the suitability of sweetgum (Liquidambar styraciflua L.) for specific sites or the efficiency of nutrient use. To gain a better understanding of these interactions, 2-year-old sweetgum seedlings from two half-sib families were tested for growth response to N (0 and 100 kg/ha equivalent) and P (0 and 50 kg...

  17. MAPLE: a Canadian multipurpose reactor concept for national nuclear development

    International Nuclear Information System (INIS)

    Lidstone, R.F.

    1984-06-01

    Atomic Energy of Canada Limited, following an investigation of Canadian and international needs and world-market prospects for research reactors, has developed a new multipurpose concept, called MAPLE (Multipurpose Applied Physics Lattice Experimental). The MAPLE concept combines H 2 O- and D 2 O-moderated lattices within a D 2 O calandria tank in order to achieve the flux advantages of a basic H 2 O-cooled and moderated core along with the flexibility and space of a D 2 O-moderated core. The SUGAR (Slowpoke Uprated for General Applied Research) MAPLE version of the conept provides a range of utilization that is well suited to the needs of countries with nuclear programs at an early stage. The higher power MAPLE version furnishes high neutron flux levels and the variety of irradiation facilities that are appropriate for more advanced nuclear programs

  18. MAPLE-II. A program for plotting fault trees

    International Nuclear Information System (INIS)

    Poucet, A.; Van Den Muyzenberg, C.L.

    1987-01-01

    The MAPLE II code is an improved version of the MAPLE program for plotting fault trees. MAPLE II has added features which make it a versatile tool for drawing large and complex logic trees. The code is developed as part of a package for computer aided fault tree construction and analysis in which it is integrated and used as a documentation tool. However the MAPLE II code can be used as a separate program which uses as input a structure function of a tree and a description of the events and gates which make up the tree. This report includes a short description of the code and of its features. Moreover it contains the how-to-use and some indications for implementing the code and for adapting it to different graphics systems

  19. Influence of gelatinous fibers on the shrinkage of silver maple

    Science.gov (United States)

    Donals G. Arganbright; Dwight W. Bensend; Floyd G. Manwiller

    1970-01-01

    The degree of lean was found to have a significant influence on the logitudinal and transverse shrinkage of three soft maple trees. This may be accounted for by differences in the cell wall layer thickness and fibril angle.

  20. Organic heterostructures based on arylenevinylene oligomers deposited by MAPLE

    Czech Academy of Sciences Publication Activity Database

    Socol, M.; Preda, N.; Vacareanu, L.; Grigoras, M.; Socol, G.; Mihailescu, I. N.; Stanculescu, F.; Jelínek, Miroslav; Stanculescu, A.; Stoicanescu, M.

    2014-01-01

    Roč. 302, May (2014), s. 216-222 ISSN 0169-4332 Institutional support: RVO:68378271 Keywords : organic heterostructures * MAPLE * oligomer * optoelectronica Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.711, year: 2014

  1. Nonlinear physics with Maple for scientists and engineers

    CERN Document Server

    Enns, Richard H

    1997-01-01

    Philosophy of the Text This text has been designed to be an introductory survey of the basic concepts and applied mathematical methods of nonlinear science. Students in engineer­ ing, physics, chemistry, mathematics, computing science, and biology should be able to successfully use this text. In an effort to provide the students with a cutting edge approach to one of the most dynamic, often subtle, complex, and still rapidly evolving, areas of modern research-nonlinear physics-we have made extensive use of the symbolic, numeric, and plotting capabilities of Maple V Release 4 applied to examples from these disciplines. No prior knowledge of Maple or computer programming is assumed, the reader being gently introduced to Maple as an auxiliary tool as the concepts of nonlinear science are developed. The diskette which accompanies the text gives a wide variety of illustrative nonlinear examples solved with Maple. An accompanying laboratory manual of experimental activities keyed to the text allows the student the...

  2. Proteomics and Transcriptomics analysis of Arabidopsis Seedlings in Microgravity

    Data.gov (United States)

    National Aeronautics and Space Administration — On Earth plants are constantly exposed to a gravitational field of 1g. Gravity affects a plant in every step of its development. Germinating seedlings orient their...

  3. The effect of osmopriming on germination, seedling growth and ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... affecting the oxidative metabolism such as increasing superoxide dismutase ... the adverse effect of salinity by improving germination and seedling growth .... osmoregulation by the accumulation of proline. A positive effect of ...

  4. Increased air temperature during simulated autumn conditions does not increase photosynthetic carbon gain but affects the dissipation of excess energy in seedlings of the evergreen Conifer Jack Pine

    OpenAIRE

    Busch, F.; Huner, N.; Ensminger, I.

    2007-01-01

    Temperature and daylength act as environmental signals that determine the length of the growing season in boreal evergreen conifers. Climate change might affect the seasonal development of these trees, as they will experience naturally decreasing daylength during autumn, while at the same time warmer air temperature will maintain photosynthesis and respiration. We characterized the down-regulation of photosynthetic gas exchange and the mechanisms involved in the dissipation of energy in Jack ...

  5. The Role of Forest Tent Caterpillar Defoliations and Partial Harvest in the Decline and Death of Sugar Maple

    Science.gov (United States)

    Hartmann, Henrik; Messier, Christian

    2008-01-01

    Background and Aims Natural and anthropogenic disturbances can act as stresses on tree vigour. According to Manion's conceptual model of tree disease, the initial vigour of trees decreases as a result of predisposing factors that render these trees more vulnerable to severe inciting stresses, stresses that can then cause final vigour decline and subsequent tree death. This tree disease model was tested in sugar maple (Acer saccharum) by assessing the roles of natural and anthropogenic disturbances in tree decline and death. Methods Radial growth data from 377 sugar maple trees that had undergone both defoliations by insects and partial harvest were used to estimate longitudinal survival probabilities as a proxy for tree vigour. Radial growth rates and survival probabilities were compared among trees subjected to different levels of above- and below-ground disturbances, between periods of defoliation and harvest, and between live and dead trees. Key Results Manion's tree disease model correctly accounts for vigour decline and tree death in sugar maple; tree growth and vigour were negatively affected by a first defoliation, predisposing these trees to death later during the study period due to a second insect outbreak that initiated a final vigour decline. This decline was accelerated by the partial harvest disturbance in 1993. Even the most severe anthropogenic disturbances from partial harvest did not cause, unlike insect defoliation, any growth or vigour declines in live sugar maple. Conclusions Natural disturbances acted as predisposing and inciting stresses in tree sugar maple decline and death. Anthropogenic disturbances from a partial harvest at worst accelerated a decline in trees that were already weakened by predisposing and inciting stresses (i.e. repeated insect defoliations). Favourable climatic conditions just before and after the partial harvest may have alleviated possible negative effects on growth resulting from harvesting. PMID:18660493

  6. Estabelecimento de plântulas e desempenho de plantas em resposta ao vigor dos aquênios de girassol Seedlings establishment and plants performance as affected by sunflower achenes vigour

    Directory of Open Access Journals (Sweden)

    Madelon Rodrigues Sá Braz

    2009-10-01

    sunflower achenes, cultivar 'Embrapa 122 V2000', with distinct vigorous levels. Plant population was evaluated at 10, 20, 40, 60, 80 and 100 days after sowing (DAS. Plant height, leaf number, stem diameter and dry matter production were evaluated at 20, 40, 60, 80 and 100DAS. At harvest (100DAS the number of achenes per plant, mass of 1000 achenes and achenes yield (g plant-1 and kg ha-1 were also evaluated. Two and six months after harvest, the achenes were submitted to the following tests: germination, first count, accelerated aging, seedling emergence in sand, length of seedlings and electrical conductivity. The results indicated that achenes vigour affected plant population at 60DAS. Vigorous sunflower achenes improved the development of plants beyond 60DAS and this effect may persist until the final production, at initial population absence.

  7. Increased air temperature during simulated autumn conditions does not increase photosynthetic carbon gain but affects the dissipation of excess energy in seedlings of the evergreen conifer Jack pine.

    Science.gov (United States)

    Busch, Florian; Hüner, Norman P A; Ensminger, Ingo

    2007-03-01

    Temperature and daylength act as environmental signals that determine the length of the growing season in boreal evergreen conifers. Climate change might affect the seasonal development of these trees, as they will experience naturally decreasing daylength during autumn, while at the same time warmer air temperature will maintain photosynthesis and respiration. We characterized the down-regulation of photosynthetic gas exchange and the mechanisms involved in the dissipation of energy in Jack pine (Pinus banksiana) in controlled environments during a simulated summer-autumn transition under natural conditions and conditions with altered air temperature and photoperiod. Using a factorial design, we dissected the effects of daylength and temperature. Control plants were grown at either warm summer conditions with 16-h photoperiod and 22 degrees C or conditions representing a cool autumn with 8 h/7 degrees C. To assess the impact of photoperiod and temperature on photosynthesis and energy dissipation, plants were also grown under either cold summer (16-h photoperiod/7 degrees C) or warm autumn conditions (8-h photoperiod/22 degrees C). Photosynthetic gas exchange was affected by both daylength and temperature. Assimilation and respiration rates under warm autumn conditions were only about one-half of the summer values but were similar to values obtained for cold summer and natural autumn treatments. In contrast, photosynthetic efficiency was largely determined by temperature but not by daylength. Plants of different treatments followed different strategies for dissipating excess energy. Whereas in the warm summer treatment safe dissipation of excess energy was facilitated via zeaxanthin, in all other treatments dissipation of excess energy was facilitated predominantly via increased aggregation of the light-harvesting complex of photosystem II. These differences were accompanied by a lower deepoxidation state and larger amounts of beta-carotene in the warm autumn

  8. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York

    Science.gov (United States)

    Sullivan, Timothy J.; Lawrence, Gregory B.; Bailey, Scott W.; McDonnell, Todd C.; McPherson, G.T.

    2013-01-01

    This study documents the effects of acidic deposition and soil acid-base chemistry on the growth, regeneration, and canopy condition of sugar maple (SM) trees in the Adirondack Mountains of New York. Sugar maple is the dominant canopy species throughout much of the northern hardwood forest in the State. A field study was conducted in 2009 in which 50 study plots within 20 small Adirondack watersheds were sampled and evaluated for soil acid-base chemistry and SM growth, canopy condition, and regeneration. Atmospheric sulfur (S) and nitrogen (N) deposition were estimated for each plot. Trees growing on soils with poor acid-base chemistry (low exchangeable calcium and % base saturation) that receive relatively high levels of atmospheric S and N deposition exhibited little to no SM seedling regeneration, decreased canopy condition, and short-to long-term growth declines compared with study plots having better soil condition and lower levels of atmospheric deposition. These results suggest that the ecosystem services provided by SM in the western and central Adirondack Mountain region, including aesthetic, cultural, and monetary values, are at risk from ongoing soil acidification caused in large part by acidic deposition.

  9. Effect of enhanced UV-B radiation of adaxial leaf surface micromorphology and epicuticular wax biosynthesis of sugar maple

    International Nuclear Information System (INIS)

    Gordon, D.C.; Percy, K.E.; Riding, R.T.

    1998-01-01

    Sugar maple (Acer saccharum [Marsh.]) seedlings were exposed to UV-B BE ranging from 0.61 kJ m -2 d -1 to 12.48 kJ m -2 d -1 . Increasing UV-B intensity was associated with changes in micromorphological characteristics of the adaxial leaf surface. In vivo incorporation of [1- 14 C] acetate into sugar maple adaxial leaf surface epicuticular wax indicated (p<0.05) a UV-B sensitivity threshold at or near 6.2 kJ m -2 d -1 . Exposure to dosages greater than 6.2 kJ m -2 d -1 resulted in a significant (p<0.05) decrease in wax biosynthesis. The proportion of [1- 14 C] acetate incorporated into each of the different epicuticular wax classes changed with increasing UV-B. Incorporation of [1- 14 C] acetate into alkyl esters decreased while incorporation into alkanes increased with increasing UV-B dose. The effects of enhanced UV-B dose recorded in this experiment may have implications for cuticle function. (author)

  10. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York

    Science.gov (United States)

    Sullivan, Timothy J.; Lawrence, Gregory B.; Bailey, Scott W.; McDonnell, Todd C.; Beier, Colin M.; Weathers, K.C.; McPherson, G.T.; Bishop, Daniel A.

    2013-01-01

    We documented the effects of acidic atmospheric deposition and soil acidification on the canopy health, basal area increment, and regeneration of sugar maple (SM) trees across the Adirondack region of New York State, in the northeastern United States, where SM are plentiful but not well studied and where widespread depletion of soil calcium (Ca) has been documented. Sugar maple is a dominant canopy species in the Adirondack Mountain ecoregion, and it has a high demand for Ca. Trees in this region growing on soils with poor acid–base chemistry (low exchangeable Ca and % base saturation [BS]) that receive relatively high levels of atmospheric sulfur and nitrogen deposition exhibited a near absence of SM seedling regeneration and lower crown vigor compared with study plots with relatively high exchangeable Ca and BS and lower levels of acidic deposition. Basal area increment averaged over the 20th century was correlated (p < 0.1) with acid–base chemistry of the Oa, A, and upper B soil horizons. A lack of Adirondack SM regeneration, reduced canopy condition, and possibly decreased basal area growth over recent decades are associated with low concentrations of nutrient base cations in this region that has undergone soil Ca depletion from acidic deposition.

  11. Root-Crown Relations of Young Sugar Maple and Yellow Birch

    Science.gov (United States)

    Carl H. Tubbs

    1977-01-01

    Young forest-grown sugar maple and yellow birch (1 to 6 inches d.b.h.) crowns were mapped and roots excavated. Crown dimensions were compared. Sugar maple roots usually terminated within a few feet of the crown perimeter. Yellow birch roots frequently terminated well outside crown perimeters and roots of birch were more irregularly distributed than those of maple....

  12. Population dynamics of sugar maple through the southern portion of its range: implications for range migration

    Science.gov (United States)

    Justin L. Hart; Christopher M. Oswalt; Craig M. Turberville

    2014-01-01

    The range of sugar maple (Acer saccharum Marsh.) is expected to shift northward in accord with changing climate. However, a pattern of increased sugar maple abundance has been reported from sites throughout the eastern US. The goal of our study was to examine the stability of the sugar maple southern range boundary by analyzing its demography through...

  13. Using Maple to Implement eLearning Integrated with Computer Aided Assessment

    Science.gov (United States)

    Blyth, Bill; Labovic, Aleksandra

    2009-01-01

    Advanced mathematics courses have been developed and refined by the first author, using an action research methodology, for more than a decade. These courses use the computer algebra system (CAS) Maple in an "immersion mode" where all presentations and student work are done using Maple. Assignments and examinations are Maple files downloaded from…

  14. Effects of air injection during sap processing on maple syrup color, chemical composition and flavor volatiles.

    Science.gov (United States)

    Air injection (AI) is a maple sap processing technology reported to increase the efficiency of maple syrup production by increasing production of more economically valuable light-colored maple syrup, and reducing development of loose scale mineral precipitates in syrup, and scale deposits on evapora...

  15. Longleaf Pine Root System Development and Seedling Quality in Response to Copper Root Pruning and Cavity Size

    Science.gov (United States)

    Mary Anne Sword Sayer; Shi-Jean Susana Sung; James D. Haywood

    2011-01-01

    Cultural practices that modify root system structure in the plug of container-grown seedlings have the potential to improve root system function after planting. Our objective was to assess how copper root pruning affects the quality and root system development of longleaf pine seedlings grown in three cavity sizes in a greenhouse. Copper root pruning increased seedling...

  16. Development and preliminary validation of flux map processing code MAPLE

    International Nuclear Information System (INIS)

    Li Wenhuai; Zhang Xiangju; Dang Zhen; Chen Ming'an; Lu Haoliang; Li Jinggang; Wu Yuanbao

    2013-01-01

    The self-reliant flux map processing code MAPLE was developed by China General Nuclear Power Corporation (CGN). Weight coefficient method (WCM), polynomial expand method (PEM) and thin plane spline (TPS) method were applied to fit the deviation between measured and predicted detector signal results for two-dimensional radial plane, to interpolate or extrapolate the non-instrumented location deviation. Comparison of results in the test cases shows that the TPS method can better capture the information of curved fitting lines than the other methods. The measured flux map data of the Lingao Nuclear Power Plant were processed using MAPLE as validation test cases, combined with SMART code. Validation results show that the calculation results of MAPLE are reasonable and satisfied. (authors)

  17. Safety features of the MAPLE-X10 reactor design

    International Nuclear Information System (INIS)

    Lee, A.G.; Bishop, W.E.; Heeds, W.

    1990-09-01

    The MAPLE-X10 reactor is a D 2 0-reflected, H 2 0-cooled and -moderated pool-type reactor under construction at the Chalk River Nuclear Laboratories. This 10-MW reactor will produce key medical and industrial radio-isotopes such as 99 Mo, 125 I, and 192 Ir. As the prototype for the MAPLE research reactor concept, the reactor incorporates diverse safety features both inherent in the design and in the added engineered systems. The safety requirements are analogous to those of the Canadian CANDU power reactor since standards for the licensing of new research reactors have not been developed yet by the licensing authority in Canada

  18. Safety features of the MAPLE-X10 reactor design

    International Nuclear Information System (INIS)

    Lee, A.G.; Bishop, W.E.; Heeds, W.

    1990-01-01

    This paper reports on the MAPLE-X10 reactor D 2 O-reflected, H 2 O-cooled and -moderated pool- type reactor, under construction at the Chalk River Nuclear Laboratories. This 10-MW will produce key medical and industrial radioisotopes such as 99 Mo, 125 I, and 192 Ir. The prototype for the MAPLE research reactor concept, the reactor incorporates diverse safety features both inherent in the design and in the added engineered systems. The safety requirements are analogous to those of the Canadian CANDU power reactor as standards for the licensing of new research reactors have not been developed by the licensing authority in Canada

  19. Impact of climate change, seedling type and provenance on the risk of damage to Norway spruce (Picea abies (L.) Karst.) seedlings in Sweden due to early summer frosts

    Energy Technology Data Exchange (ETDEWEB)

    Langvall, Ola (Swedish Univ. of Agricultural Sciences, Unit for Field-based Forest Research, Asa Forest Research Station, Lammhult (Sweden))

    2011-04-15

    A model including site-specific microclimate-affecting properties of a forest regeneration area together with seedling characteristics was used to evaluate the accumulated risk of frost damage to Norway spruce (Picea abies (L.) Karst.) seedlings. Climate change in Sweden was simulated on the basis of the regional climate model RCA3. The daily average temperature, the driving factor for bud burst in the model, was adjusted using the difference between the mean of the climate model data for the years 1961-1990 and 2036-2065. The model was run for a highly frost prone, clear-cut site in which bare-rooted Norway spruce seedlings of mid-Swedish provenance were planted. Alternate runs were conducted with data for containerized seedlings and seedlings of Belarusian origin. The study showed that bud burst will occur at earlier dates throughout Sweden in the period 2036-2065 if the climate changes according to either of the climate scenarios examined, compared to the reference period 1961-1990. Furthermore, the risk of damage to Norway spruce seedlings as a result of frost events during summer will increase in southern Sweden and be unaffected or decrease in northern Sweden. The risk of frost damage was exacerbated in containerized seedlings, while the risk was lower for the seedlings of Belarusian provenance when compared with bare-rooted seedlings or seedlings of mid-Swedish origin

  20. Phenylbutyrate therapy for maple syrup urine disease.

    Science.gov (United States)

    Brunetti-Pierri, Nicola; Lanpher, Brendan; Erez, Ayelet; Ananieva, Elitsa A; Islam, Mohammad; Marini, Juan C; Sun, Qin; Yu, Chunli; Hegde, Madhuri; Li, Jun; Wynn, R Max; Chuang, David T; Hutson, Susan; Lee, Brendan

    2011-02-15

    Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate in urea cycle disorder patients has been associated with a selective reduction in branched-chain amino acids (BCAA) in spite of adequate dietary protein intake. Based on this clinical observation, we investigated the potential of phenylbutyrate treatment to lower BCAA and their corresponding α-keto acids (BCKA) in patients with classic and variant late-onset forms of maple syrup urine disease (MSUD). We also performed in vitro and in vivo experiments to elucidate the mechanism for this effect. We found that BCAA and BCKA are both significantly reduced following phenylbutyrate therapy in control subjects and in patients with late-onset, intermediate MSUD. In vitro treatment with phenylbutyrate of control fibroblasts and lymphoblasts resulted in an increase in the residual enzyme activity, while treatment of MSUD cells resulted in the variable response which did not simply predict the biochemical response in the patients. In vivo phenylbutyrate increases the proportion of active hepatic enzyme and unphosphorylated form over the inactive phosphorylated form of the E1α subunit of the branched-chain α-keto acid dehydrogenase complex (BCKDC). Using recombinant enzymes, we show that phenylbutyrate prevents phosphorylation of E1α by inhibition of the BCKDC kinase to activate BCKDC overall activity, providing a molecular explanation for the effect of phenylbutyrate in a subset of MSUD patients. Phenylbutyrate treatment may be a valuable treatment for reducing the plasma levels of neurotoxic BCAA and their corresponding BCKA in a subset of MSUD patients and studies of its long-term efficacy are indicated.

  1. Winter survival of Scots pine seedlings under different snow conditions.

    Science.gov (United States)

    Domisch, Timo; Martz, Françoise; Repo, Tapani; Rautio, Pasi

    2018-04-01

    Future climate scenarios predict increased air temperatures and precipitation, particularly at high latitudes, and especially so during winter. Soil temperatures, however, are more difficult to predict, since they depend strongly on the fate of the insulating snow cover. 'Rain-on-snow' events and warm spells during winter can lead to thaw-freeze cycles, compacted snow and ice encasement, as well as local flooding. These adverse conditions could counteract the otherwise positive effects of climatic changes on forest seedling growth. In order to study the effects of different winter and snow conditions on young Scots pine (Pinus sylvestris L.) seedlings, we conducted a laboratory experiment in which 80 1-year-old Scots pine seedlings were distributed between four winter treatments in dasotrons: ambient snow cover (SNOW), compressed snow and ice encasement (ICE), flooded and frozen soil (FLOOD) and no snow (NO SNOW). During the winter treatment period and a 1.5-month simulated spring/early summer phase, we monitored the needle, stem and root biomass of the seedlings, and determined their starch and soluble sugar concentrations. In addition, we assessed the stress experienced by the seedlings by measuring chlorophyll fluorescence, electric impedance and photosynthesis of the previous-year needles. Compared with the SNOW treatment, carbohydrate concentrations were lower in the FLOOD and NO SNOW treatments where the seedlings had almost died before the end of the experiment, presumably due to frost desiccation of aboveground parts during the winter treatments. The seedlings of the ICE treatment showed dead needles and stems only above the snow and ice cover. The results emphasize the importance of an insulating and protecting snow cover for small forest tree seedlings, and that future winters with changed snow patterns might affect the survival of tree seedlings and thus forest productivity.

  2. Affect

    NARCIS (Netherlands)

    Cetinic, M.; Diamanti, J.; Szeman, I.; Blacker, S.; Sully, J.

    2017-01-01

    This chapter historicizes four divergent but historically contemporaneous genres of affect theory – romantic, realist, speculative, and materialist. While critics credited with the turn to affect in the 1990s wrote largely in the wake of poststructuralism from the perspective of gender and queer

  3. Strong microsite control of seedling recruitment in tundra

    DEFF Research Database (Denmark)

    Graae, Bente J; Ejrnæs, Rasmus; Lang, Simone I

    2011-01-01

    The inclusion of environmental variation in studies of recruitment is a prerequisite for realistic predictions of the responses of vegetation to a changing environment. We investigated how seedling recruitment is affected by seed availability and microsite quality along a steep environmental......, the experimental seed addition showed that the microsite environment was even more important. For all species, seedling emergence peaked at the productive end of the gradient, irrespective of the adult niches realized. Disturbance promoted recruitment at all positions along the environmental gradient, not just...... at high productivity. Early seedling emergence constituted the main temporal bottleneck in recruitment for all species. Surprisingly, winter mortality was highest at what appeared to be the most benign end of the gradient. The results highlight that seedling recruitment patterns are largely determined...

  4. Indledning til Maple for Lineær Algebra

    DEFF Research Database (Denmark)

    Sinclair, Robert

    1999-01-01

    Denne rapport er en undersoegelse af hvordan og hvor vidt Maplesindbyggede kommandoer passer til Jens Eisings bog "Lineaer Algebra" (1997).Maalet er at beskrive, hvordan man bedst kan brugeMaple V Release 5.1i kurset,i viden om mulige problemer, saa man kan undgaa faelder,og svare paa studerendes...

  5. HOW to Control Sapstreak Disease of Sugar Maple

    Science.gov (United States)

    Kenneth K. Jr. Kessler

    1978-01-01

    Sapstreak disease, caused by the fungus Ceratocystis coerulescens, is a serious threat to sugar maple forests. Although the disease is causing only minor damage at present, it has the potential to become an important problem. Sapstreak is a fatal disease; infected trees do not recover. In addition, timber salvage value is low because the wood is discolored.

  6. The Multiple Pendulum Problem via Maple[R

    Science.gov (United States)

    Salisbury, K. L.; Knight, D. G.

    2002-01-01

    The way in which computer algebra systems, such as Maple, have made the study of physical problems of some considerable complexity accessible to mathematicians and scientists with modest computational skills is illustrated by solving the multiple pendulum problem. A solution is obtained for four pendulums with no restriction on the size of the…

  7. Student Organizations in Canada and Quebec's "Maple Spring"

    Science.gov (United States)

    Bégin-Caouette, Olivier; Jones, Glen A.

    2014-01-01

    This article has two major objectives: to describe the structure of the student movement in Canada and the formal role of students in higher education governance, and to describe and analyze the "Maple Spring," the dramatic mobilization of students in opposition to proposed tuition fee increases in Quebec that eventually led to a…

  8. Potential causes of the pear thrips outbreak in sugar maple

    Science.gov (United States)

    Jack C. Schultz

    1991-01-01

    No one knows what caused the 1988 outbreak of pear thrips, Taeniothrips inconsequens (Uzel), in sugar maple, Acer saccharum Marsh., in the northeastern United States. As an entomologist and ecologist who knows even less about this insect than most of the authors of this volume, I cannot presume to understand the causes of this...

  9. MAPLE applications in a studiyng organic thin films

    Czech Academy of Sciences Publication Activity Database

    Jelínek, Miroslav; Kocourek, Tomáš; Remsa, Jan; Cristescu, R.; Mihailescu, I. N.; Chrisey, D.B.

    2007-01-01

    Roč. 17, č. 1 (2007), s. 66-70 ISSN 1054-660X R&D Projects: GA ČR GA202/06/0216 Institutional research plan: CEZ:AV0Z10100522 Keywords : MAPLE * PLD * MDW * laser * target Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.696, year: 2007

  10. Foliar nutrient analysis of sugar maple decline: retrospective vector diagnosis

    Science.gov (United States)

    Victor R. Timmer; Yuanxin Teng

    1999-01-01

    Accuracy of traditional foiiar analysis of nutrient disorders in sugar maple (Acer saccharum Marsh) is limited by lack of validation and confounding by nutrient interactions. Vector nutrient diagnosis is relatively free of these problems. The technique is demonstrated retrospectively on four case studies. Diagnostic interpretations consistently...

  11. [Effects of gap size on seedling natural regeneration in artificial Pinus tabulaeformis plantation].

    Science.gov (United States)

    Han, Wen-Juan; Yuan, Xiao-Qing; Zhang, Wen-Hui

    2012-11-01

    To clarify the effects of gap size created by thinning on the seedling natural regeneration in artificial Pinus tabulaeformis plantation, a plot investigation was conducted to study the ecological factors and the age structure, height, diameter, length of needles, and dry biomass of roots, stems, and needles of 1-10 year-old seedlings in different habitats, and a path analysis was made on the environmental factors affecting the seedling regeneration. Obvious differences were observed in the ecological factors in different size gaps and slope aspects. There lacked of above 3 year-old seedlings in understory and of above 7 year-old seedlings in small gap, and the seedlings of 5 and 6 year-old were lesser in big gap. The 1-10 year-old seedlings could be divided into 3 development phases, i. e. , 1-3 year-old, 4-7 year-old, and 8-10 year-old seedlings, among which, 1-3 year-old seedlings were critical for the establishment and growth of the population. The growth situation of the seedlings in different habitats was in order of big gap in shady slope > big gap in sunny slope > small gap in sunny slope > small gap in shady slope > understory in sunny slope > understory in shady slope. Path analysis showed light intensity had decisive positive effects on the seedling number of different development phases, shrub coverage had decisive negative effects on the seedling number of 4-7 year-old and 8-10 year-old phases, whereas humus dry mass had negative effects on the seedling number of 4-7 year-old but positive effects on the seedling number of 8-10 year-old. It was suggested that in the management of artificial P. tabulaeformis plantation, relatively high intensity thinning combined with shrub clearing should be adopted to provide favorable conditions for the sustainable development of P. tabulaeformis population.

  12. Acclimation and soil moisture constrain sugar maple root respiration in experimentally warmed soil.

    Science.gov (United States)

    Jarvi, Mickey P; Burton, Andrew J

    2013-09-01

    The response of root respiration to warmer soil can affect ecosystem carbon (C) allocation and the strength of positive feedbacks between climatic warming and soil CO2 efflux. This study sought to determine whether fine-root (maple (Acer saccharum Marsh.)-dominated northern hardwood forest would adjust to experimentally warmed soil, reducing C return to the atmosphere at the ecosystem scale to levels lower than that would be expected using an exponential temperature response function. Infrared heating lamps were used to warm the soil (+4 to +5 °C) in a mature sugar maple forest in a fully factorial design, including water additions used to offset the effects of warming-induced dry soil. Fine-root-specific respiration rates, root biomass, root nitrogen (N) concentration, soil temperature and soil moisture were measured from 2009 to 2011, with experimental treatments conducted from late 2010 to 2011. Partial acclimation of fine-root respiration to soil warming occurred, with soil moisture deficit further constraining specific respiration rates in heated plots. Fine-root biomass and N concentration remained unchanged. Over the 2011 growing season, ecosystem root respiration was not significantly greater in warmed soil. This result would not be predicted by models that allow respiration to increase exponentially with temperature and do not directly reduce root respiration in drier soil.

  13. Effect of dark-colored maple syrup on cell proliferation of human gastrointestinal cancer cell

    Science.gov (United States)

    Yamamoto, Tetsushi; Sato, Kanta; Kubota, Yuika; Mitamura, Kuniko; Taga, Atsushi

    2017-01-01

    Maple syrup is a natural sweetener that is commonly consumed worldwide. While maple syrup mainly comprises sucrose, it also contains phytochemicals that present various biological effects. Maple syrup is made by boiling down sap, and its color and composition vary in accordance with the sap collection season. Typically, seasonal progression is associated with darker syrup color, and antioxidant activity is proportional to the increasingly dark color. The authors previously reported that maple syrup demonstrated inhibitory effects on colorectal cancer cell growth and invasion, which correlated with darker maple syrup color. In the present study, they examined the effects of two different grades of maple syrup on gastrointestinal cancer cell proliferation, to investigate whether the dark-color maple syrup was suitable as a phytomedicine for gastrointestinal cancer treatment. Administration of dark-color maple syrup significantly inhibited gastrointestinal cancer cell growth as compared to non-treated cancer cells. Moreover, administration of dark-color maple syrup clearly inhibited protein kinase B (AKT) phosphorylation and did not impact mitogen-associated protein kinase phosphorylation. These data suggested that dark-color maple syrup may inhibit cell proliferation through suppression of AKT activation and, thus, may be suitable as a phytomedicine for gastrointestinal cancer treatment. PMID:28685052

  14. Effects of seed mass on seedling success in Artocarpus heterophyllus L., a tropical tree species of north-east India

    Science.gov (United States)

    Khan, M. L.

    2004-03-01

    I examined the effects of seed mass on performance of seedlings of Artocarpus heterophyllus L. (Moraceae), a large evergreen late successional shade-tolerant tree species in three contrasting light conditions. Seed mass varied many fold from 1.5 to 14 g in A. heterophyllus. Germination and germination time showed a significant correlation with seed mass. Germination differed significantly among three light regimes (50%, 25% and 3%). Seed mass and light level significantly affected seedling survival. The seedlings that emerged from large seeds survived better than those from small seeds under all light regimes. Survival of seedlings was maximum in 25% light regime for all seed mass classes but did not differ significantly from that at 50% light regime. Survival was significantly lower in 3% light as compared to 50% and 25% light regimes. Seedling vigor (expressed in terms of seedling height, leaf area and dry weight) was also significantly affected by seed mass and light regimes. Seedlings that emerged from larger seeds and grew under 50% light regime produced the heaviest seedlings, while those resulting from smaller seeds and grown under 3% light regime produced the lightest seedlings. Resprouting capacity of seedlings after clipping was significantly affected by seed mass and light regime. Seedlings emerging from larger seeds were capable of resprouting several times successively. Resprouting was more pronounced under 50% and 25% light regimes as compared to 3% light. Success of A. heterophyllus regeneration appears to be regulated by an interactive effect of seed mass and light regime.

  15. Colonization with Arbuscular Mycorrhizal Fungi Promotes the Growth of Morus alba L. Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2015-03-01

    Full Text Available Morus alba L. is an important tree species planted widely in China because of its economic value. In this report, we investigated the influence of two arbuscular mycorrhizal fungal (AMF species, Glomus mosseae and Glomus intraradices, alone and together, on the growth of M. alba L. seedlings under greenhouse conditions. The growth parameters and physiological performance of M. alba L. seedlings were evaluated 90 days after colonization with the fungi. The growth and physiological performance of M. alba L. seedlings were significantly affected by the AMF species. The mycorrhizal seedlings were taller, had longer roots, more leaves and a greater biomass than the non-mycorrhizae-treated seedlings. In addition, the AMF species-inoculated seedlings had increased root activity and a higher chlorophyll content compared to non-inoculated seedlings. Furthermore, AMF species colonization increased the phosphorus and nitrogen contents of the seedlings. In addition, simultaneous root colonization by the two AMF species did not improve the growth of M. alba L. seedlings compared with inoculation with either species alone. Based on these results, these AMF species may be applicable to mulberry seedling cultivation.

  16. Effects of Seedbed Density on Seedling Morphological Characteristics of four Broadleaved Species

    Energy Technology Data Exchange (ETDEWEB)

    Yucedag, C.; Gailing, O.

    2012-11-01

    The aim of this study was to investigate the effects of seedling spacing on morphological characteristics of one year-old Amygdalus communis L., Prunus avium L., Pyrus elaeagnifolia Pall. and Eriolobus trilobatus (Poiret) Roemer seedlings under nursery conditions. Seedlings were grown in completely randomized blocks with four replications. Seedbeds were 1.2 m wide with 5 rows each 20 cm apart. Within-row spacings were chosen as 4, 8 and 12 cm to analyze the effect of seedlings density on growth performance. Seedling spacing significantly affected root collar diameter, shoot height, tap root length and number of fine roots in A. communis and P. avium, but not in P. elaeagnifolia and E. tribolatus. Additionally wider seedling spacings resulted in larger seedlings in A. communis and P. avium. In conclusion, it would be beneficial to use wider seedling spacing in order to obtain better seedling growth in A. communis and P. avium. Larger seedlings could also provide significant advantages because of reduced cultural activities and an expected higher growth and survival rate. (Author) 27 refs.

  17. Effect of peanut shells amendment on soil properties and growth of seedlings of Senegalia senegal (L.) Britton, Vachellia seyal (Delile) P. Hurter, and Prosopis juliflora (Swartz) DC in salt-affected soils

    OpenAIRE

    Fall, D.; Bakhoum, N.; Fall, F.; Diouf, F.; Ndiaye, C.; Faye, M. N.; Hocher, Valérie; Diouf, D.

    2018-01-01

    Key message The soil amendment with peanut shells (4, 6 or 8 t ha(-1)) improves soil properties and growth of Senegalia senegal (L.) Britton, Vachellia seyal (Delile) P. Hurter and Prosopis juliflora (Swartz) DC seedlings on salty soils (86, 171, 257 mM NaCl). Context Salinization causes the degradation of biological, chemical, and physical properties of soils. Salty soils reclamation can be achieved with organic amendments and afforestation with salt tolerant species.Aims The aim of the stud...

  18. Crescimento radicular de plântulas de milho afetado pela resistência do solo à penetração Root growth of corn seedlings as affected by soil resistance to penetration

    Directory of Open Access Journals (Sweden)

    Ciro Antonio Rosolem

    1999-05-01

    Full Text Available A resistência do solo à penetração é relacionada com a textura, compactação e umidade do solo. No presente trabalho se estudou o efeito da interação desses fatores sobre o crescimento de raízes de milho. Materiais de solo com 22, 30, 34, 41 e 48% de argila foram acondicionados em tubos de PVC de 10 cm com 4,3 cm de diâmetro interno, nas densidades globais de 1,07, 1,18, 1,36 e 1,53 g cm-3, em três tensões de água: -0,034, -0,106 e -0,640 MPa. Plântulas de milho foram cultivadas nos tubos por 48 horas. Quando a densidade do solo é baixa, a textura tem papel preponderante no crescimento radicular. Esse efeito é menor à medida que aumenta a densidade global. O aumento da resistência do solo à penetração causa diminuição no comprimento e número de raízes seminais adventícias; a raiz seminal primária mostra menor capacidade de penetração do que as raízes seminais adventícias. Resistências do solo à penetração da ordem de 1,3 MPa reduzem à metade o crescimento das raízes seminais adventícias do milho.The soil resistance to penetration is affected by soil texture, compaction and moisture content. In this paper, the effects of the interaction of these factors on corn root growth was studied. Soil materials with 22, 30, 34, 41 and 48% of clay were packed in PVC tubes 10 cm high, with 4.3 cm of internal diameter to reach bulk densities of 1.07, 1.18, 1.36 and 1.53 g cm-3. Water was added to reach water potentials of -0.034, -0.106 and -0.640 MPa. Corn seedlings were grown in the tubes for 48 hours. When the soil bulk density was low, root growth was affected mainly by soil texture. As soil bulk density increased, there was a decrease in the effect of soil texture on root growth. The increase in soil strength caused a decrease in root length and in the number of seminal adventitious roots. The primary roots showed a lower penetration ability when compared to seminal adventitious roots. A soil resitance of 1.3 MPa

  19. DETERMINATION OF THE SEEDLINGS QUALITY CLASSES OF BLACK LOCUST (Robinia pseudoacacia L. ORIGINS

    Directory of Open Access Journals (Sweden)

    İbrahim Turna

    2000-04-01

    Full Text Available classification criteria is the assesment of height and root-colar diameter together. newly seedling quality classification (YS have highly first grade seedlings. The most important According to the results of this study, all the origins determined with respect to either TSE or determined by using factor analysis. Furthermore the morphological characteristics that affect the seedling quality classification were diameter. The resulting seedling quality classification were controlled by using discriminant analysis. determined according to height, root-colar diameter and combination of both height and root-colar provenances were soved in KTÜ Nursery. One year later, these seedlings were lifted. Quality norms in KTÜ Nursery were used. Eighteen different origin seeds of Black locust of which eleven are egzotic In this present study, 1+0 Black Locust ( Robinia pseudoacacia L. seedlings grown

  20. Effects of sand burial and seed size on seed germination, seedling emergence and seedling biomass of anabasis aphylla

    International Nuclear Information System (INIS)

    Wang, T.T.; Chu, G.M.; Jiang, P.; Wang, M.

    2017-01-01

    Two greenhouse experiments were conducted to test the effects of sand burial (0-2 cm) and seed size (small, medium and large) on seed germination and seedling growth of Anabasis aphylla, which is typically used as a windbreak and for the fixation of sand in the Gurbantunggut desert of Xinjiang, region of northwest China. The results showed that sand burial significantly affected seed germination, seedling emergence, survival and biomass of A. aphylla. The seed germination rate, seedling emergence rate, seedling survival rate and biomass were highest at the 0.2 and 0.5 cm sand burial depths. At different burial depths, different sizes of A. aphylla seed showed a significant difference in the germination and emergence rate. At the same sand burial depth, the seedling emergence rate of the large seeds was significantly higher than that of medium and small seeds. At sand burial depth of 0.2-2 cm, germination of large seeds and seedling survival rates were significantly higher than those at the same sand burial depth for medium seed germination, and the latter was significantly higher than for small seed. We speculate that tolerance to sand burial and diversity of seed size increased the adaption of A. aphylla to this environment, contributing to its dominance in the windy and sandy area of Gurbantunggut desert. (author)

  1. Biogeochemical cycling of Mg and its isotopes in a sugar maple forest in Québec

    Science.gov (United States)

    Kimmig, Sara R.; Holmden, Chris; Bélanger, Nicolas

    2018-06-01

    A Mg isotope study of sugar maple (Acer saccharum Marsh.) in a field site in southern Québec, Canada, and seedlings grown in sterile soil substrate in the laboratory, both demonstrate per mil level within-tree Mg isotope fractionation. However, only sugar maple seedlings grown in the laboratory fractionate Mg isotopes during uptake into fine roots, favoring heavy isotope enrichment in the plant compared to the growth medium. Absence of uptake-related Mg isotope fractionation in field stands of sugar maple is tentatively attributed to the activities of the arbuscular mycorrhizal fungi that colonize fine roots of the trees in the field, but were absent from the laboratory grown specimens. The fungi facilitate nutrient uptake for the tree, while the tree provides valuable carbohydrates to the fungi. Without the symbiotic fungi, pot-grown trees in the laboratory are visibly stressed and often die. The mechanisms responsible for Mg isotopic fractionation in stressed trees remain to be elucidated. Rivers are isotopically light compared to bedrock weathering sources of Mg, and this has bearing on the δ26Mg value of the continental weathering flux of Mg to the oceans, which is an important parameter in studies of ocean Mg cycling in the geological past. If uptake-related fractionation is negligible in many other naturally growing tree species, as it is in sugar maple, then forest growth will exert little or no influence on the δ26Mg value of the export flux of Mg to first-order streams and rivers, and in turn the ocean Mg cycle. Above the tree line, preferential retention of heavy Mg isotopes in clay minerals formed during silicate weathering has been linked to the low δ26Mg values in rivers. In the forested catchment of this study there is no clear evidence for these effects. The 1 N HNO3 leach of the Bf-BC and C mineral soils, which are often used to identify minerals that may be releasing Mg and other base cations to plant-available pools, have the same average δ26

  2. The MAPLE-X concept dedicated to the production of radio-isotopes

    International Nuclear Information System (INIS)

    Heeds, W.

    1985-06-01

    MAPLE is a versatile new Canadian multi-purpose research reactor concept that meets the nuclear aspirations of developing countries. It is planned to convert the NRX reactor at Chalk River Nuclear Laboratories into MAPLE-X as a demonstration prototype of this concept and thereafter to dedicate its operation to the production of radio-isotopes. A description of MAPLE-X and details of molybdenum-99 production are given

  3. Water ice as a matrix for film production by matrix-assisted pulsed laser evaporation (MAPLE)

    International Nuclear Information System (INIS)

    Rodrigo, K; Schou, J; Toftmann, B; Pedrys, R

    2007-01-01

    We have studied water ice as a matrix for the production of PEG (polyethylene glycol) films by MAPLE at 355 nm. The deposition rate is small compared with other matrices typically used in MAPLE, but the deposition of photofragments from the matrix can be avoided. At temperatures above -50deg. C of the target holder the deposition rate increases strongly, but the evaporation pressure in the MAPLE chamber also increases drastically

  4. Isolation, Identification, and Biological Evaluation of Phenolic Compounds from a Traditional North American Confectionery, Maple Sugar.

    Science.gov (United States)

    Liu, Yongqiang; Rose, Kenneth N; DaSilva, Nicholas A; Johnson, Shelby L; Seeram, Navindra P

    2017-05-31

    Maple sap, collected from the sugar maple (Acer saccharum) tree, is boiled to produce the popular plant-derived sweetener, maple syrup, which can then be further evaporated to yield a traditional North American confectionery, maple sugar. Although maple sap and maple syrup have been previously studied, the phytochemical constituents of maple sugar are unknown. Herein, 30 phenolic compounds, 1-30, primarily lignans, were isolated and identified (by HRESIMS and NMR) from maple sugar. The isolates included the phenylpropanoid-based lignan tetramers (erythro,erythro)-4″,4‴-dihydroxy-3,3',3″,3‴,5,5'-hexamethoxy-7,9';7',9-diepoxy-4,8″;4',8‴-bisoxy-8,8'-dineolignan-7″,7‴,9″,9‴-tetraol, 29, and (threo,erythro)-4″,4‴-dihydroxy-3,3',3″,3‴,5,5'-hexamethoxy-7,9';7',9-diepoxy-4,8″;4',8‴-bisoxy-8,8'-dineolignan-7″,7‴,9″,9‴-tetraol, 30, neither of which have been identified from maple sap or maple syrup before. Twenty of the isolates (selected on the basis of sample quantity available) were evaluated for their potential biological effects against lipopolysaccharide-induced inflammation in BV-2 microglia in vitro and juglone-induced oxidative stress in Caenorhabditis elegans in vivo. The current study increases scientific knowledge of possible bioactive compounds present in maple-derived foods including maple sugar.

  5. Water ice as a matrix for film production by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Rodrigo, Katarzyna Agnieszka; Schou, Jørgen; Christensen, Bo Toftmann

    2007-01-01

    We have studied water ice as a matrix for the production of PEG (polyethylene glycol) films by MAPLE at 355 nm. The deposition rate is small compared with other matrices typically used in MAPLE, but the deposition of photofragments from the matrix can be avoided. At temperatures above -50 degrees C...... of the target holder the deposition rate increases strongly, but the evaporation pressure in the MAPLE chamber also increases drastically....

  6. Methyl gallate is a natural constituent of maple (Genus Acer) leaves.

    Science.gov (United States)

    Abou-Zaid, Mamdouh M; Lombardo, Domenic A; Nozzolillo, Constance

    2009-01-01

    Methyl gallate was found in ethanolic extracts of red maple (Acer rubrum L.), silver maple (A. saccharinum L.) and sugar maple (A. saccharum Marsh) leaves, but more was present in methanolic extracts. The increased amount of methyl gallate in methanolic extracts was accompanied by a disappearance of m-digallate. It is concluded that only some of the methyl gallate detected in methanolic extracts is an artefact as a result of methanolysis of m-digallate. Its presence in ethanolic extracts is evidence that it is also a natural constituent of maple leaves.

  7. Inhibitory effect of maple syrup on the cell growth and invasion of human colorectal cancer cells.

    Science.gov (United States)

    Yamamoto, Tetsushi; Uemura, Kentaro; Moriyama, Kaho; Mitamura, Kuniko; Taga, Atsushi

    2015-04-01

    Maple syrup is a natural sweetener consumed by individuals of all ages throughout the world. Maple syrup contains not only carbohydrates such as sucrose but also various components such as organic acids, amino acids, vitamins and phenolic compounds. Recent studies have shown that these phenolic compounds in maple syrup may possess various activities such as decreasing the blood glucose level and an anticancer effect. In this study, we examined the effect of three types of maple syrup, classified by color, on the cell proliferation, migration and invasion of colorectal cancer (CRC) cells in order to investigate whether the maple syrup is suitable as a phytomedicine for cancer treatment. CRC cells that were administered maple syrup showed significantly lower growth rates than cells that were administered sucrose. In addition, administration of maple syrup to CRC cells caused inhibition of cell invasion, while there was no effect on cell migration. Administration of maple syrup clearly inhibited AKT phosphorylation, while there was no effect on ERK phosphorylation. These data suggest that maple syrup might inhibit cell proliferation and invasion through suppression of AKT activation and be suitable as a phytomedicine for CRC treatment, with fewer adverse effects than traditional chemotherapy.

  8. Red maple (Acer rubrum) leaf toxicosis in horses: a retrospective study of 32 cases.

    Science.gov (United States)

    Alward, Ashley; Corriher, Candice A; Barton, Michelle H; Sellon, Debra C; Blikslager, Anthony T; Jones, Samuel L

    2006-01-01

    Ingestion of wilted red maple leaves by horses can result in severe hemolytic anemia and methemoglobinemia. Little is known about what factors influence the outcome of red maple leaf toxicosis in horses. Our hypothesis was that physical examination findings, clinicopathologic variables or therapeutic modalities may predict outcome in horses with red maple leaf toxicity. Horses with red maple leaf toxicosis presented to referral hospitals in the southeast region of the United States. A multi-institutional retrospective study was designed to identify factors that predict mortality in horses with red maple toxicosis. Thirty-two horses with red maple toxicosis were identified, 19 of which died. Twenty-nine horses presented with anemia and 24 had clinicopathologic evidence of systemic inflammation. Renal insufficiency was identified in 12/30 (41%) horses. Laminitis (9/28) and colic (13/30) also were identified in horses with red maple toxicosis, but development of these 2 conditions did not have a negative effect on short-term survival. Horses with red maple toxicosis that survived to discharge were likely to have developed pyrexia during hospitalization (P = .030). Horses that were treated with a corticosteroid had a significantly increased likelihood of death (P = .045). There was no significant relationship between initial serum hemoglobin concentration, methemoglobin concentration, or percentage methemoglobin and mortality in this horse series. This study suggests that information obtained on initial examination cannot be used to accurately predict survival in horses with red maple toxicosis, but horses that receive corticosteroids are unlikely to survive.

  9. Scientific computing an introduction using Maple and Matlab

    CERN Document Server

    Gander, Walter; Kwok, Felix

    2014-01-01

    Scientific computing is the study of how to use computers effectively to solve problems that arise from the mathematical modeling of phenomena in science and engineering. It is based on mathematics, numerical and symbolic/algebraic computations and visualization. This book serves as an introduction to both the theory and practice of scientific computing, with each chapter presenting the basic algorithms that serve as the workhorses of many scientific codes; we explain both the theory behind these algorithms and how they must be implemented in order to work reliably in finite-precision arithmetic. The book includes many programs written in Matlab and MapleMaple is often used to derive numerical algorithms, whereas Matlab is used to implement them. The theory is developed in such a way that students can learn by themselves as they work through the text. Each chapter contains numerous examples and problems to help readers understand the material “hands-on”.

  10. Theoretical physics IV. Quantum mechanics with problems in MAPLE

    International Nuclear Information System (INIS)

    Reinecker, Peter; Schulz, Michael; Schulz, Beatrix M.

    2008-01-01

    Quantum mechanics 2 is the fourth volume of the new and unique series for theoretical physics with Maple applications. This from basics newly concipated series mediates theoretical physics from contemporary view and in a way referring to a comprehensive lecture experience. Extensively and completely in five consecutively appearing volumes classical mechanics, electrodynamics, quantum mechanics 1 and 2, as well as statistical physics and thermodynamics are presented. Additionally for the elegant and extensive presentation on an each added CP applications for MAPLE trademark are contained, the software, which at more and more university is already applied in the lecture. They allow the experimenting with theory - and facilitate the understanding essentially. The present volume mediates extending, more complex contents of quantum mechanics, which are based on volume III of the series

  11. Sap-Sugar Content of Grafted Sugar Maple Trees

    Science.gov (United States)

    Maurice E. Jr. Demeritt; Maurice E. Jr. Demeritt

    1985-01-01

    In March and April 1983, 289 and 196 young grafted sugar maple trees were tapped and evaluated for sap-sugar content. In April, sap was collected from taps both above and below the graft union. Diameter of all tapped trees at 18 inches above the ground was measured. Analysis of the data revealed that: (1) trees selected for high sugar yield cannot be reproduced by...

  12. Phenolic glycosides from sugar maple (Acer saccharum) bark.

    Science.gov (United States)

    Yuan, Tao; Wan, Chunpeng; González-Sarrías, Antonio; Kandhi, Vamsikrishna; Cech, Nadja B; Seeram, Navindra P

    2011-11-28

    Four new phenolic glycosides, saccharumosides A-D (1-4), along with eight known phenolic glycosides, were isolated from the bark of sugar maple (Acer saccharum). The structures of 1-4 were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for cytotoxicity effects against human colon tumorigenic (HCT-116 and Caco-2) and nontumorigenic (CCD-18Co) cell lines.

  13. Cost of Maple Sap Production for Various Size Tubing Operations

    Science.gov (United States)

    Niel K. Huyler

    2000-01-01

    Reports sap production costs for small (500 to 1,000 taps), medium (1,000 to 5,000), and large (5,000 to 15,000) maple syrup operations that use plastic tubing with vacuum pumping. The average annual operating cost per tap ranged from $4.64 for a 500-tap sugarbush operation to $1.84 for a sugarbush with 10,000 taps. The weighted average was $2.87 per tap or $11.48 per...

  14. Improving students’ understanding of mathematical concept using maple

    Science.gov (United States)

    Ningsih, Y. L.; Paradesa, R.

    2018-01-01

    This study aimed to improve students’ understanding of mathematical concept ability through implementation of using Maple in learning and expository learning. This study used a quasi-experimental research with pretest-posttest control group design. The sample on this study was 61 students in the second semester of Mathematics Education of Universitas PGRI Palembang, South Sumatera in academic year 2016/2017. The sample was divided into two classes, one class as the experiment class who using Maple in learning and the other class as a control class who received expository learning. Data were collective through the test of mathematical initial ability and mathematical concept understanding ability. Data were analyzed by t-test and two ways ANOVA. The results of this study showed (1) the improvement of students’ mathematical concept understanding ability who using Maple in learning is better than those who using expository learning; (2) there is no interaction between learning model and students’ mathematical initial ability toward the improvement of students’ understanding of mathematical concept ability.

  15. Comparative Analysis of Milled Wood Lignins (MWLs Isolated from Sugar Maple (SM and Hot-Water Extracted Sugar Maple (ESM

    Directory of Open Access Journals (Sweden)

    Mangesh J. Goundalkar

    2014-03-01

    Full Text Available To further elucidate the advantageous effects of hot-water extraction (HWE on delignification, milled wood lignin (MWL was isolated from sugar maple (SM and from hot-water extracted sugar maple (ESM. Ball-milled wood was analyzed for particle size distribution (PSD before and after dioxane:water (DW extraction. The MWL samples were analyzed by analytical and spectral methods. The results indicated that the MWL isolated from SM and ESM was mainly released from the middle lamella (ML and the secondary wall (SW, respectively. The cleavage of dibenzodioxocin (DB and spirodienone (SD lignin substructures during HWE is suggested. The removal of lignin during acetone:water (AW extraction of hot-water extracted wood indicates that including an additional operation in a hardwood HWE-based biorefinery would be beneficial for processing of wood.

  16. The Effects of Electron Beam Irradiation Dose on the Mechanical Performance of Red Maple (Acer rubrum

    Directory of Open Access Journals (Sweden)

    Timothy Starr

    2014-12-01

    Full Text Available To understand how electron beam irradiation affects wood physically and chemically, irradiated maple beams (Acer rubrum and veneers were examined using three-point bend tests, dynamic mechanical analysis (DMA, and NIR- and FTIR- spectroscopy. The MOR from the bending tests revealed a significant decline in the red maple’s strength after a dose of 80 kGy. DMA results showed evidence of crosslinking of the amorphous content of the wood at low doses, followed by degradation at higher doses, with the change in response occurring around 80 kGy. Infrared spectroscopy revealed that the components of wood that were most impacted were the phenolic hydroxyl structures of lignin and cellulose hydroxyls, with the greatest effects being seen after 80 kGy.

  17. The management of pregnancy in maple syrup urine disease: experience with two patients.

    Science.gov (United States)

    Tchan, Michel; Westbrook, M; Wilcox, G; Cutler, R; Smith, N; Penman, R; Strauss, B J G; Wilcken, B

    2013-01-01

    We describe the management and outcomes of pregnancy in two women affected with Maple syrup urine disease (MSUD). Both patients had classical disease diagnosed in the newborn period and were managed with low-protein diets and supplements, although compliance was moderately poor throughout life. Both pregnancies were complicated by poor compliance and one patient had a metabolic decompensation, which included seizures and profound encephalopathy, at the end of the first trimester. Peri-partum management required a coordinated team approach including a high-calorie and low-protein diet. Both patients had elevated leucine levels in the post-partum period - one due to mastitis and the other due to poor dietary and supplement compliance combined with uterine involution. On later review, leucine had returned to pre-pregnancy levels. Both infants were unaffected and have made normal developmental progress in the subsequent 1 to 2 years.

  18. Effects of Different Ectomycorrhizal Fungal Inoculates on the Growth of Pinus tabulaeformis Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2016-12-01

    Full Text Available The tree species Pinus tabulaeformis Carr. (P. tabulaeformis is commonly planted in China due to its economic and ecological value. In order to identify one or more ectomycorrhizal (ECM fungal species for future P. tabulaeformis afforestation, we investigated the effects of five ECM fungal species: Laccaria laccata, Boletus edulis, Gomphidius viscidus, Suillus grevillei, and Suillus luteus on the growth of P. tabulaeformis seedlings under greenhouse conditions. The growth parameters of P. tabulaeformis seedlings were evaluated 90 days following fungal colonisation. The majority of seedlings were significantly affected by ECM inoculation. Mycorrhizal inoculated seedlings were taller, had more lateral roots, and a greater biomass compared with the non-mycorrhizal (CK seedlings. With the exception of G. viscidus, inoculated seedlings exhibited higher phosphorus, potassium, and nitrogen content compared with the CK seedlings. In addition, ECM colonisation increased the enzymatic activity of catalase, acidic phosphatase, protease, and the urease content in the rhizosphere soil. Our study showed that Laccaria laccata, Suillus grevillei, and Suillus luteus may be useful for improving the growth and cultivation of P. tabulaeformis seedlings. Furthermore, we observed that S. luteus inoculation increased the gas exchange parameters of P. tabulaeformis seedlings under field conditions.

  19. Development of seedlings of watermelon cv. Crimson Sweet irrigated with biosaline water

    Directory of Open Access Journals (Sweden)

    José E. S. B. da Silva

    2015-09-01

    Full Text Available ABSTRACTThe limited access and the scarcity of good quality water for agriculture are some of the major problems faced in agricultural areas, particularly in arid and semiarid regions. The aim of this study was to evaluate the quality of watermelon seedlings (cv. Crimson Sweet, irrigated with different concentrations of biosaline water of fish culture. The experimental design was completely randomized with five treatments, corresponding to biosaline water at different concentrations (0, 33, 50, 67 and 100%, and four replicates of 108 seedlings. Watermelon seeds were sown in plastic trays filled with commercial substrate and irrigated with different solutions of biosaline water. Seedlings were harvested for biometric analysis at 14, 21 and 28 days after sowing. The use of biosaline water did not affect emergence and establishment of seedlings until 14 days after sowing, the period recommended for transplantation. However, the use of biosaline water affected the development of seedlings with longer exposure time.

  20. Study on tissue culture for Gelidium seedling

    Science.gov (United States)

    Pei, Lu-Qing; Luo, Qi-Jun; Fei, Zhi-Qing; Ma, Bin

    1996-06-01

    As seedling culture is a crucial factor for successful cultivation of Gelidium, the authors researched tissue culture technology for producing seedlings. The morphogeny and experimental ecology were observed and studied fully in 2 5 mm isolated tissue fragments. Regeneration, appearance of branching creepers and attaching structure and new erect seedlings production and development were studied. Fragments were sown on bamboo slice and vinylon rope. The seedlings were cultured 20 30 days indoor, then cultured in the sea, where the density of erect seedlings was 3 19 seedlings/cm2, growth rate was 3.84% day. The frond arising from seedlings directly was up to 10 cm per year. The ecological conditions for regenerated seedlings are similar to the natural ones. The regenerated seedlings are suitable for raft culture in various sea areas.

  1. Use of damage surveys and field inventories to evaluate oak and sugar maple health in the northern United States

    Science.gov (United States)

    Randall S Morin; Christopher W. Woodall; Jim Steinman; Charles H. Perry

    2009-01-01

    Oak species (Quercus spp.) and sugar maple (Acer saccharum) are substantial components of the forest ecosystems in the 24-state region spanning the northern U.S. During recent decades, both damage surveys and forest inventories have documented declines of sugar maple and oak health. In order to more fully assess the status of oak and sugar maple health, we examined...

  2. Glyoxalase I expression pattern in Hevea brasiliensis seedlings ...

    African Journals Online (AJOL)

    Glyoxalase I expression pattern in Hevea brasiliensis seedlings under varied stress conditions. MVP Siraj, A Thulaseedharan, Anu Augustine. Abstract. Drought is one of the most important stress factors which adversely affect plants' growth and productivity. Global climate change may make this situation more serious in the ...

  3. Effect of Trichoderma isolates on tomato seedling growth response ...

    African Journals Online (AJOL)

    Jane

    2011-06-29

    Jun 29, 2011 ... Seed germination rate was not affected by Trichoderma application, but .... system architecture under sterile condition (Bjorkman et al. ... MATERIALS AND METHODS .... of application to tomato seed in seedling shoot and root elements content. .... with production of some organic acids in the rhizosphere.

  4. The Influence of Residual Stand Densities on Regeneration in Sugar Maple Stands

    Science.gov (United States)

    Carl H. Tubbs

    1968-01-01

    Studies of regeneration 2, 5, and 10 years after cutting mature and overmature sugar maple stands to several residual densities show that (1) sugar maple is still the predominant species under all stand densities (2) nearly all regeneration reaching larger size classes became established before cutting (3) heavier cuttings (30, 50, and 70 square feet) are more rapidly...

  5. Passive Maple-Seed Robotic Fliers for Education, Research and Entrepreneurship

    Science.gov (United States)

    Aslam, D. M.; Abu-Ageel, A.; Alfatlawi, M.; Varney, M. W.; Thompson, C. M.; Aslam, S. K.

    2014-01-01

    As inspirations from flora and fauna have led to many advances in modern technology, the concept of drawing ideas from nature for design should be reflected in engineering education. This paper focuses on a maple-seed robotic flier (MRF) with various complexities, a robotic platform modeled after the samaras of maple or ash trees, to teach STEM…

  6. The relationship between measures of tree vigor and pear thrips damage in sugar maple

    Science.gov (United States)

    Gretchen Smith; Christina M. Petersen; Roy Van Driesche; Charles Burnham

    1991-01-01

    In this presentation I will address three points associated with pear thrips damage and sugar maple. First, I will describe the impact of pear thrips on sugar maple in Massachusetts, in both the sugarbush and the natural forest stand, based on root starch assays that were completed this fall (1988). Secondly, I will discuss the relationship between tree health and...

  7. Processing of C60 thin films by Matrix-Assisted Pulsed Laser Evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2011-01-01

    Thin films of fullerenes (C60) were deposited onto silicon using matrix-assisted pulsed laser evaporation (MAPLE). The deposition was carried out from a frozen homogeneous dilute solution of C60 in anisole (0.67 wt%), and over a broad range of laser fluences, from 0.15 J/cm2 up to 3.9 J/cm2. MAPLE...

  8. Hypoglycin A in maple trees in the Netherlands and the risk of equine atypical myopathy

    NARCIS (Netherlands)

    Westermann, C.M.; van Leeuwen, Robbert; Mol, Hans

    2016-01-01

    The Acer (maple) genus of trees comprises over 120 species worldwide. Some of these contain the plant-toxin hypoglycin-A which has been proven to be a cause of the highly fatal condition called atypical myopathy (AM) in horses and ponies. In an earlier study of maple-tree samples (leaves and seeds)

  9. Sugar maple: abundance and site relationships in the pre- and post- settlement forest

    Science.gov (United States)

    Gordon G. Whitney

    1999-01-01

    A review of the available historical evidence provides a picture of sugar maple's site relationstiips in the presettlement forest and its changing statis over the last 300 years. Sugar maple was widely distributed throughout the Northeast during the presettlerment period. it was particularly abundant on the richer, better drained, silt-rich sites. A comparison of...

  10. Crown releasing of red maple poles to shorten high-quality sawlog rotations

    Science.gov (United States)

    Gayne G. Erdmann; Ralph M., Jr. Peterson; Robert R. Orberg

    1985-01-01

    The effects of six crown-release treatments on growth and bole quality development of 54-year-old dominant, codominant, and intermediate red maples (Acer rubrum L.) were evaluated on a good red maple site (site index = 19.3 mat 50 years) in upper Michigan. Results showed that crown release stimulated the growth of dominants, codominants, and strong...

  11. Influence of demographic characteristics on production practices within the Ohio maple syrup industry

    Science.gov (United States)

    Gary W. Graham; P. Charles Goebel; Randall B. Heiligmann; Matthew S. Bumgardner

    2007-01-01

    Maple syrup production contributes approximately $5 million annually to Ohio's economy and provides supplemental nontimber forest product income for forestland owners. To better understand the factors that influence this important nontimber forest industry in Ohio, including producer heritage, producer age, sap collection methods, size of maple operation, and...

  12. Chronic drought stress reduced but not protected Shantung maple (Acer truncatum Bunge) from adverse effects of ozone (O3) on growth and physiology in the suburb of Beijing, China

    International Nuclear Information System (INIS)

    Li, Li; Manning, William J.; Tong, Lei; Wang, Xiaoke

    2015-01-01

    A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O 3 ) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012–2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (A sat ) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O 3 – induced reductions in A sat , Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O 3 . - Highlights: • The response of Acer truncatum Bunge to drought and ozone was investigated. • Drought could mitigate the foliage injury and leaf photosynthetic pigments. • The O 3 -induced reductions in Asat, Gs and total biomass were enhanced by drought. - Drought didn't protect Shantung maple from O 3 effects but rather cause more reductions in biomass

  13. Potential production of Aspidosperma cylindrocarpon seedlings viarescue seedlings

    Directory of Open Access Journals (Sweden)

    Nathália Ferreira e Silva

    Full Text Available ABSTRACT: Translocation of rare populations is regarded as the last resort for the conservation of species whose habitat destruction is imminent. The objective of the present study was to evaluate the effect of two height classes and three leaf reduction intensities on growth and increases in height, stem diameter, survival, and new leaf production in seedlings of Aspidosperma cylindrocarpon (peroba obtained via rescue seedlings in a remnant of tropical semi deciduous forest. We recovered 240 individuals that were divided into two height classes (Class I-5 to 15cm and Class II-20 to 35cm and subjected to three leaf reduction intensities (0%, 50%, and 100%, which were then transported to a shade house with 50% light reduction. Measurements of height, stem diameter, and new leaf production were collected 8 times at 0, 15, 60, 75, 90, 105, 120, and 135 days, and survival rate was measured at day 135. The average survival rate was 82.9%; 77.5% for one Class I (5-15cm and 88.3% for Class II (20-35cm. Higher seedling growth was observed for the 0% leaf reduction treatment in both height classes. The leaves insertion were greater in the 100% cuts, with a decrease observed over time. It is advisable to restore A. cylindrocarpon seedlings in two height classes owing to the high survival rate, leaf appearance, and growth reported in the present study. The no-leaf reduction treatment (0% is the most viable alternative for the production of A. cylindrocarpon seedlings, via rescue seedlings.

  14. Seedling performance within eight different seed-size alpine forbs under experimentation with irradiance and nutrient gradients

    International Nuclear Information System (INIS)

    Dong, W.; Jun, Z.Y.; Lin, W.G.; Jin, F.

    2014-01-01

    Relative performance of seedlings of species with different seed sizes may vary in response to resource availability, and may affect seedling growth. The objective was to test this hypothesis from alpine forbs species in the Qinghai-Tibetan Plateau. We examined the relative growth rate, allocation and performances of eight native forbs species covering a wide range of seed size in response to four light and three nutrient regimes. Light availability had a significant effect on seedling emergence time, but not on other seedling morphological performances. Seedling emergence time and seed size were negatively correlated with each other for three species within Asteraceae family, i.e. heaviest seeds emerged earlier. Seed size, nutrient availability and their interaction affected most of studied morphological and growth traits of seedlings. Fertilisation modified the relationship between seed size and seedling biomass. Our study showed that seed size and nutrient availability had significant effects on seedling performance in alpine meadows. Seedlings from the larger-seed species presented stronger advantage in initial seedling mass and height under most of resources conditions. (author)

  15. AtRH57, a DEAD-box RNA helicase, is involved in feedback inhibition of glucose-mediated abscisic acid accumulation during seedling development and additively affects pre-ribosomal RNA processing with high glucose.

    Science.gov (United States)

    Hsu, Yi-Feng; Chen, Yun-Chu; Hsiao, Yu-Chun; Wang, Bing-Jyun; Lin, Shih-Yun; Cheng, Wan-Hsing; Jauh, Guang-Yuh; Harada, John J; Wang, Co-Shine

    2014-01-01

    The Arabidopsis thaliana T-DNA insertion mutant rh57-1 exhibited hypersensitivity to glucose (Glc) and abscisic acid (ABA). The other two rh57 mutants also showed Glc hypersensitivity similar to rh57-1, strongly suggesting that the Glc-hypersensitive feature of these mutants results from mutation of AtRH57. rh57-1 and rh57-3 displayed severely impaired seedling growth when grown in Glc concentrations higher than 3%. The gene, AtRH57 (At3g09720), was expressed in all Arabidopsis organs and its transcript was significantly induced by ABA, high Glc and salt. The new AtRH57 belongs to class II DEAD-box RNA helicase gene family. Transient expression of AtRH57-EGFP (enhanced green fluorescent protein) in onion cells indicated that AtRH57 was localized in the nucleus and nucleolus. Purified AtRH57-His protein was shown to unwind double-stranded RNA independent of ATP in vitro. The ABA biosynthesis inhibitor fluridone profoundly redeemed seedling growth arrest mediated by sugar. rh57-1 showed increased ABA levels when exposed to high Glc. Quantitative real time polymerase chain reaction analysis showed that AtRH57 acts in a signaling network downstream of HXK1. A feedback inhibition of ABA accumulation mediated by AtRH57 exists within the sugar-mediated ABA signaling. AtRH57 mutation and high Glc conditions additively caused a severe defect in small ribosomal subunit formation. The accumulation of abnormal pre-rRNA and resistance to protein synthesis-related antibiotics were observed in rh57 mutants and in the wild-type Col-0 under high Glc conditions. These results suggested that AtRH57 plays an important role in rRNA biogenesis in Arabidopsis and participates in response to sugar involving Glc- and ABA signaling during germination and seedling growth. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  16. Influence of mycorrhizal associations on paper birch and jack pine seedlings when exposed to elevated copper, nickel or aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Jones, M.D.; Browning, M.H.R.; Hutchinson, T.C.

    1986-10-01

    Acid deposition may adversely affect northern forest ecosystems by increasing the concentration of metals in the soil solution. This study investigates the effects of ectomycorrhizal fungi on paper birch and jack pine seedlings exposed to elevated Cu, Ni or Al in sand culture. One of four mycorrhizal fungi, Scleroderma flavidum, was able to reduce Ni toxicity to the birch seedlings. It did this by reducing transport of Ni to the stems. None of the fungi affected Cu toxicity in birch. In separate experiments, jack pine seedlings were exposed to combinations of Al and Ca. Infection with Rhizopogon rubescens increased seedling susceptibility to Al. Seedlings inoculated with Suillus tomentosus showed a greater growth stimulation by Ca than uninoculated jack pines. Thus, for both tree species, the mycorrhizal association could alter the response of seedlings to high concentrations of certain metals, although this varied with fungal species. 8 references.

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

    Directory of Open Access Journals (Sweden)

    Wrzesiński Piotr

    2015-09-01

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

  18. Radiation effects on Brassica seeds and seedlings

    Science.gov (United States)

    Deoli, Naresh; Hasenstein, Karl H.

    2016-07-01

    Space radiation consists of high energy charged particles and affects biological systems, but because of its stochastic, non-directional nature is difficult to replicate on Earth. Radiation damages biological systems acutely at high doses or cumulatively at low doses through progressive changes in DNA organization. These damages lead to death or cause of mutations. While radiation biology typically focuses on mammalian or human systems, little is known as to how radiation affects plants. In addition, energetic ion beams are widely used to generate new mutants in plants considering their high-LET (Linear Energy Transfer) as compared to gamma rays and X-rays. Understanding the effect of ionizing radiation on plant provides a basis for studying effects of radiation on biological systems and will help mitigate (space) radiation damage in plants. We exposed dry and imbibed Brassica rapa seeds and seedling roots to proton beams of varying qualities and compared the theoretical penetration range of different energy levels with observable growth response. We used 1, 2 and 3 MeV protons in air at the varying fluences to investigate the effect of direct irradiation on the seeds (1012 - 1015 ions/cm2) and seedlings (1013 ions/cm2). The range of protons in the tissue was calculated using Monte-Carlo based SRIM (Stopping and Range of Ions in Matter) software. The simulation and biological results indicate that ions did not penetrate the tissue of dry or hydrated seeds at all used ion energies. Therefore the entire energy was transferred to the treated tissue. Irradiated seeds were germinated vertically under dim light and roots growth was observed for two days after imbibition. The LD50 of the germination was about 2×1014 ions/cm2 and about 5×1014 ions/cm2 for imbibed and dry seeds, respectively. Since seedlings are most sensitive to gravity, the change in gravitropic behavior is a convenient means to assess radiation damage on physiological responses other than direct tissue

  19. Gene expression in plant lipid metabolism in Arabidopsis seedlings.

    Directory of Open Access Journals (Sweden)

    An-Shan Hsiao

    Full Text Available Events in plant lipid metabolism are important during seedling establishment. As it has not been experimentally verified whether lipid metabolism in 2- and 5-day-old Arabidopsis thaliana seedlings is diurnally-controlled, quantitative real-time PCR analysis was used to investigate the expression of target genes in acyl-lipid transfer, β-oxidation and triacylglycerol (TAG synthesis and hydrolysis in wild-type Arabidopsis WS and Col-0. In both WS and Col-0, ACYL-COA-BINDING PROTEIN3 (ACBP3, DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1 and DGAT3 showed diurnal control in 2- and 5-day-old seedlings. Also, COMATOSE (CTS was diurnally regulated in 2-day-old seedlings and LONG-CHAIN ACYL-COA SYNTHETASE6 (LACS6 in 5-day-old seedlings in both WS and Col-0. Subsequently, the effect of CIRCADIAN CLOCK ASSOCIATED1 (CCA1 and LATE ELONGATED HYPOCOTYL (LHY from the core clock system was examined using the cca1lhy mutant and CCA1-overexpressing (CCA1-OX lines versus wild-type WS and Col-0, respectively. Results revealed differential gene expression in lipid metabolism between 2- and 5-day-old mutant and wild-type WS seedlings, as well as between CCA1-OX and wild-type Col-0. Of the ACBPs, ACBP3 displayed the most significant changes between cca1lhy and WS and between CCA1-OX and Col-0, consistent with previous reports that ACBP3 is greatly affected by light/dark cycling. Evidence of oil body retention in 4- and 5-day-old seedlings of the cca1lhy mutant in comparison to WS indicated the effect of cca1lhy on storage lipid reserve mobilization. Lipid profiling revealed differences in primary lipid metabolism, namely in TAG, fatty acid methyl ester and acyl-CoA contents amongst cca1lhy, CCA1-OX, and wild-type seedlings. Taken together, this study demonstrates that lipid metabolism is subject to diurnal regulation in the early stages of seedling development in Arabidopsis.

  20. Assessment of beam tube performance for the maple research reactor

    International Nuclear Information System (INIS)

    Lee, A.G.

    1986-06-01

    The MAPLE research reactor is a versatile new research facility that can be adapted to meet the requirements of a variety of reactor applications. A particular group of reactor applications involves the use of beams of radiation extracted from the reactor core via tubes that penetrate through the biological shield and terminate in the reflector surrounding the fuelled core. An assessment is given of the neutron and gamma radiation fields entering beam tubes that are located radially or tangentially with respect to the core

  1. Solving Nonlinear Partial Differential Equations with Maple and Mathematica

    CERN Document Server

    Shingareva, Inna K

    2011-01-01

    The emphasis of the book is given in how to construct different types of solutions (exact, approximate analytical, numerical, graphical) of numerous nonlinear PDEs correctly, easily, and quickly. The reader can learn a wide variety of techniques and solve numerous nonlinear PDEs included and many other differential equations, simplifying and transforming the equations and solutions, arbitrary functions and parameters, presented in the book). Numerous comparisons and relationships between various types of solutions, different methods and approaches are provided, the results obtained in Maple an

  2. Effects of combined drought and heavy metal stresses on xylem structure and hydraulic conductivity in red maple (Acer rubrum L.).

    Science.gov (United States)

    de Silva, Nayana Dilini Gardiyehewa; Cholewa, Ewa; Ryser, Peter

    2012-10-01

    The effects of heavy metal stress, drought stress, and their combination on xylem structure in red maple (Acer rubrum) seedlings were investigated in an outdoor pot experiment. As metal-contaminated substrate, a mixture of 1.5% slag with sand was used, with Ni, Cu, Co, and Cr as the main contaminants. Plants grown on contaminated substrate had increased leaf metal concentrations. The two stresses reduced plant growth in an additive manner. The effects of metal and drought stresses on xylem characteristics were similar to each other, with a reduced proportion of xylem tissue, reduced conduit density in stems, and reduced conduit size in the roots. This resulted, in both stems and roots, in reductions in hydraulic conductance, xylem-specific conductivity, and leaf-specific conductivity. The similarity of the responses to the two stresses suggests that the plants' response to metals was actually a drought response, probably due to the reduced water uptake capacity of the metal-exposed roots. The only plant responses specific to metal stress were decreasing trends of stomatal density and chlorophyll content. In conclusion, the exposure to metals aggravates water stress in an additive manner, making the plants more vulnerable to drought.

  3. Seedling vigor and genetic variability for rice seed, seedling emergence and seedling traits

    International Nuclear Information System (INIS)

    Ali, S.S.; Jafri, S.J.H.; Jamil, M.; Ijaz, M.

    1994-01-01

    Eleven local rice cultivars including Basmati 370 were evaluated for seedling vigor. Three groups of traits were evaluated viz; seed traits (Seed density, seed volume see weight, paddy length and grain length), seed emergence traits (emergence %, emergence index and emergence rate index), and seedling traits (fresh root length, dry root weight, emergence percentage, root length, dry root weight, seed weight and relative root weight were observed significant, respectively. Seed density, relative root weight, emergence rate index and root to shoot ratio were relatively more amenable to improvement. Relative expected genetic advance was the function of heritability and coefficient of phenotypic variability, latter being more important. (author)

  4. A Predictive Coexpression Network Identifies Novel Genes Controlling the Seed-to-Seedling Phase Transition in Arabidopsis thaliana.

    Science.gov (United States)

    Silva, Anderson Tadeu; Ribone, Pamela A; Chan, Raquel L; Ligterink, Wilco; Hilhorst, Henk W M

    2016-04-01

    The transition from a quiescent dry seed to an actively growing photoautotrophic seedling is a complex and crucial trait for plant propagation. This study provides a detailed description of global gene expression in seven successive developmental stages of seedling establishment in Arabidopsis (Arabidopsis thaliana). Using the transcriptome signature from these developmental stages, we obtained a coexpression gene network that highlights interactions between known regulators of the seed-to-seedling transition and predicts the functions of uncharacterized genes in seedling establishment. The coexpressed gene data sets together with the transcriptional module indicate biological functions related to seedling establishment. Characterization of the homeodomain leucine zipper I transcription factor AtHB13, which is expressed during the seed-to-seedling transition, demonstrated that this gene regulates some of the network nodes and affects late seedling establishment. Knockout mutants for athb13 showed increased primary root length as compared with wild-type (Columbia-0) seedlings, suggesting that this transcription factor is a negative regulator of early root growth, possibly repressing cell division and/or cell elongation or the length of time that cells elongate. The signal transduction pathways present during the early phases of the seed-to-seedling transition anticipate the control of important events for a vigorous seedling, such as root growth. This study demonstrates that a gene coexpression network together with transcriptional modules can provide insights that are not derived from comparative transcript profiling alone. © 2016 American Society of Plant Biologists. All Rights Reserved.

  5. Growing container seedlings: Three considerations

    Science.gov (United States)

    Kas Dumroese; Thomas D. Landis

    2015-01-01

    The science of growing reforestation and conservation plants in containers has continually evolved, and three simple observations may greatly improve seedling quality. First, retaining stock in its original container for more than one growing season should be avoided. Second, strongly taprooted species now being grown as bareroot stock may be good candidates...

  6. Fatores que afetam a germinação de sementes e emergência de plântulas de arruda (Ruta graveolens L. Factors affecting seed germination and seedling emergence in rue (Ruta graveolens L.

    Directory of Open Access Journals (Sweden)

    O.M. Yamashita

    2009-01-01

    Full Text Available Ruta graveolens L., também conhecida com arruda, é planta originária do sul da Europa, cultivada no Brasil e em outros países como planta medicinal, muito utilizada em rituais religiosos. Tendo em vista que a germinação constitui um fator primordial para que a semente possa gerar uma planta vigorosa e com alto potencial produtivo, o presente trabalho teve como objetivo avaliar a resposta germinativa de sementes para arruda sob condições de temperatura, luminosidade, estresse hídrico e salino e emergência de plântulas em diferentes profundidades de semeadura. Sementes de Ruta graveolens são indiferentes à luz, germinando melhor em temperatura constante de 25ºC ou alterna (20-30ºC. Os potenciais osmóticos induzidos por manitol a partir de -0,4MPa e por NaCl a partir de -0,8MPa influenciam negativamente o processo germinativo. Maiores percentuais de plântulas são obtidas quando a espécie é semeada na superfície do substrato.Ruta graveolens L., also known as rue, is from the south of Europe, cultivated in Brazil and other countries as a medicinal plant greatly used in religious rituals. Since germination is essential for the seed to generate a vigorous plant of high productive potential, this work aimed to evaluate the germinative response of rue seeds under different temperatures, luminosity conditions, and water and salt stress, besides seedling emergence at different sowing depths. Ruta graveolens L. seeds are indifferent to light, better germinating at constant temperature of 25ºC or alternated temperature (20-30ºC. The osmotic potentials induced by mannitol from -0.4MPa and by NaCl from -0.8MPa negatively influenced the germination process. Higher seedling percentages are obtained when the species is sown on the substratum surface.

  7. Salt tolerance of physalis during germination and seedling growth

    International Nuclear Information System (INIS)

    Yildirim, E.; Karlidag, H.

    2011-01-01

    The study was conducted to evaluate the effect of NaCl salinity on germination and emergence of Physalis ixocarpa and Physalis peruviana. Seeds of P. ixocarpa and P. peruviana were germinated by the use of 0, 30, 60, 90, 120 and 180 mM NaCl solutions in petri dishes. Final germination percentage (FGP) decreased with the increase in NaCl concentration. Both species germinated at the ranges of salinity. P. peruviana gave the greater germination percentages under salt stress than P. ixocarpa. NaCl salinity at different concentrations adversely affected germination rates. For seedling growth, seeds of both species were sown at 10 mm depth in plastic trays filled with peat to determine final emergence percentage (FEP). The trays were irrigated manually to saturation every day with 0, 30, 60, 90, 120, 150 or 180 mM NaCl solutions to maintain the level of salinity. Salinity affected seed emergence and seedlings growth more than seed germination. The study showed that no emergence of Physalis was observed at 90, 120 and 180 mM NaCl salinity. Fresh and dry weights of normal seedlings were also evaluated. Salt stress significantly decreased the plant fresh and dry weight of both species. Based on the results of the experiment, it can be concluded that seedling emergence and growth is more sensitive to salt stress than seed germination in Physalis. (author)

  8. An Experimental Study on the aerodynamic and aeroacoustic performances of Maple-Seed-Inspired UAV Propellers

    Science.gov (United States)

    Hu, Hui; Ning, Zhe

    2016-11-01

    Due to the auto-rotating trait of maple seeds during falling down process, flow characteristics of rotating maple seeds have been studied by many researchers in recent years. In the present study, an experimental investigation was performed to explore maple-seed-inspired UAV propellers for improved aerodynamic and aeroacoustic performances. Inspired by the auto-rotating trait of maple seeds, the shape of a maple seed is leveraged for the planform design of UAV propellers. The aerodynamic and aeroacoustic performances of the maple-seed-inspired propellers are examined in great details, in comparison with a commercially available UAV propeller purchased on the market (i.e., a baseline propeller). During the experiments, in addition to measuring the aerodynamic forces generated by the maple-seed-inspired propellers and the baseline propeller, a high-resolution Particle Image Velocimetry (PIV) system was used to quantify the unsteady flow structures in the wakes of the propellers. The aeroacoustic characteristics of the propellers are also evaluated by leveraging an anechoic chamber available at the Aerospace Engineering Department of Iowa State University. The research work is supported by National Science Foundation under Award Numbers of OSIE-1064235.

  9. Organic heterostructures deposited by MAPLE on AZO substrate

    Science.gov (United States)

    Socol, M.; Preda, N.; Stanculescu, A.; Breazu, C.; Florica, C.; Stanculescu, F.; Iftimie, S.; Girtan, M.; Popescu-Pelin, G.; Socol, G.

    2017-09-01

    Organic heterostructures based on poly(3-hexylthiophene) (P3HT) and fullerene (C60) as blends or multilayer were deposited on Al:ZnO (AZO) by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique. The AZO layers were obtained by Pulsed Laser Deposition (PLD) on glass substrate, the high quality of the films being reflected by the calculated figure of merit. The organic heterostructures were investigated from morphological, optical and electrical point of view by atomic force microscopy (AFM), UV-vis spectroscopy, photoluminescence (PL) and current-voltage (I-V) measurements, respectively. The increase of the C60 content in the blend heterostructure has as result a high roughness. Compared with the multilayer heterostructure, those based on blends present an improvement in the electrical properties. Under illumination, the highest current value was recorded for the heterostructure based on the blend with the higher C60 amount. The obtained results showed that MAPLE is a useful technique for the deposition of the organic heterostructures on AZO as transparent conductor electrode.

  10. Combinatorial MAPLE gradient thin film assemblies signalling to human osteoblasts

    International Nuclear Information System (INIS)

    Axente, Emanuel; Sima, Felix; Elena Sima, Livia; Serban, Natalia; Ristoscu, Carmen; Mihailescu, Ion N; Erginer, Merve; Toksoy Oner, Ebru; Eroglu, Mehmet S; Petrescu, Stefana M

    2014-01-01

    There is increased interest in smart bioactive materials to control tissue regeneration for the engineering of cell instructive scaffolds. We introduced combinatorial matrix-assisted pulsed laser evaporation (C-MAPLE) as a new method for the fabrication of organic thin films with a compositional gradient. Synchronized C-MAPLE of levan and oxidized levan was employed to assemble a two-compound biopolymer film structure. The gradient of the film composition was validated by fluorescence microscopy. In this study, we investigated the cell response induced by the compositional gradient using imaging of early osteoblast attachment and analysis of signalling phosphoprotein expression. Cells attached along the gradient in direct proportion to oxidized levan concentration. During this process distinct areas of the binary gradient have been shown to modulate the osteoblasts’ extracellular signal-regulated kinase signalling with different propensity. The proposed fabrication method results in the preparation of a new bioactive material, which could control the cell signalling response. This approach can be extended to screen new bioactive interfaces for tissue regeneration. (papers)

  11. Ectomycorrhizal colonization of naturally regenerating Pinus sylvestris L. seedlings growing in different micro-habitats in boreal forest.

    Science.gov (United States)

    Iwański, Michał; Rudawska, Maria

    2007-07-01

    We investigated the species richness and composition of ectomycorrhizal (EM) fungi colonizing Pinus sylvestris L. seedlings naturally regenerating in boreal forest, in three different microhabitats: on forest ground, on decaying stumps, and within moss layer on erratic boulders. We tested the hypothesis that habitat differences would affect the composition of the EM community of regenerating pine seedlings. In total, 16 EM species were detected, from which none occurred on seedlings growing in all three microhabitats. Piloderma croceum and Cenococcum geophilum were common for seedlings growing in forest ground and on boulders, while Tricholoma aestuans and Suillus luteus were shared between seedlings growing on forest ground and decaying stumps. EM species richness and composition were strikingly different between seedlings regenerating in different microhabitats. Results are discussed as a function of dispersal and niche differentiation of EM fungi.

  12. Study of Seed Germination and Morphological Characteristics of Wild Oat(Avena ludoviciana and Mustard (Sinapis arvensis Seedling, Affected by Aqueous Extracts of Black Cumin (Bunium persicum L, Chickpea (Cicer arietinum L and Mixed of Extracts

    Directory of Open Access Journals (Sweden)

    R Moradi

    2012-02-01

    Full Text Available Abstract In order to evaluate the effects of shoot aqueous extracts of chickpea, black cumin and their mixed aqueous extracts on seed germination and seedling morphological characteristics of wild oat and mustard as two common weed, an experiment was conducted with a factorial arrangement based on completely randomized design with three replications. The experimental treatments were aqueous extracts in five levels (0, 10, 20, 40 and 60 percentage, Weed species in two levels (wild oat and mustard and extract concentration in five levels (0, 10, 20. 40 and 60 percentage. Result indicated that the highest and the lowest percentage and seed germination rate, length of radicle and hypocotyle, dry weight of radicle and hypocotyle and radicle / hypocotyle ratio (R/H, were obtained in control treatment and 60% concentration, respectively. Aqueous extract of black cumin and mixed extracts had the highest and the lowest effect on percentage and seed germination rate, length of radicle and hypocotyle, dry weight of radicle and hypocotyle and radicle / hypocotyle ratio, respectively. Between two weed species, wild oat had the lowest percentage of seed germination and length of radicle compared with mustard. Mustard had the lowest seed germination rate, dry weight of radicle and hypocotyle and length of hypocotyle compare with wild oat. Generally, it was concluded that chickpea and black cumin aqueous extracts have highly inhibitory in terms of weed control that can be useful for sustainable agriculture. Keywords: Allelopathy, Black cumin, Chickpea, Extract, Mustard, Wild oat

  13. Are leaves that fall from imidacloprid-treated maple trees to control Asian longhorned beetles toxic to non-target decomposer organisms?

    Science.gov (United States)

    Kreutzweiser, David P; Good, Kevin P; Chartrand, Derek T; Scarr, Taylor A; Thompson, Dean G

    2008-01-01

    The systemic insecticide imidacloprid may be applied to deciduous trees for control of the Asian longhorned beetle, an invasive wood-boring insect. Senescent leaves falling from systemically treated trees contain imidacloprid concentrations that could pose a risk to natural decomposer organisms. We examined the effects of foliar imidacloprid concentrations on decomposer organisms by adding leaves from imidacloprid-treated sugar maple trees to aquatic and terrestrial microcosms under controlled laboratory conditions. Imidacloprid in maple leaves at realistic field concentrations (3-11 mg kg(-1)) did not affect survival of aquatic leaf-shredding insects or litter-dwelling earthworms. However, adverse sublethal effects at these concentrations were detected. Feeding rates by aquatic insects and earthworms were reduced, leaf decomposition (mass loss) was decreased, measurable weight losses occurred among earthworms, and aquatic and terrestrial microbial decomposition activity was significantly inhibited. Results of this study suggest that sugar maple trees systemically treated with imidacloprid to control Asian longhorned beetles may yield senescent leaves with residue levels sufficient to reduce natural decomposition processes in aquatic and terrestrial environments through adverse effects on non-target decomposer organisms.

  14. Container volume and subirrigation schedule influence Quercus variabilis seedling growth and nutrient status in the nursery and field

    Science.gov (United States)

    Qiaoyu Sun; R. Kasten Dumroese; Yong Liu

    2018-01-01

    Container volume and irrigation management affect seedling growth in the nursery and field. We evaluated the effects of container volumes (D40, 656 ml; D60, 983 ml) and subirrigation schedules (85%, 75%, 65%, and 55% of 100% total substrate moisture content, TSMC) on seedling growth in a greenhouse and outplanting performance of Chinese cork oak (Quercus variabilis...

  15. How fresh is maple syrup? Sugar maple trees mobilize carbon stored several years previously during early springtime sap-ascent.

    Science.gov (United States)

    Muhr, Jan; Messier, Christian; Delagrange, Sylvain; Trumbore, Susan; Xu, Xiaomei; Hartmann, Henrik

    2016-03-01

    While trees store substantial amounts of nonstructural carbon (NSC) for later use, storage regulation and mobilization of stored NSC in long-lived organisms like trees are still not well understood. At two different sites with sugar maple (Acer saccharum), we investigated ascending sap (sugar concentration, δ(13) C, Δ(14) C) as the mobilized component of stored stem NSC during early springtime. Using the bomb-spike radiocarbon approach we were able to estimate the average time elapsed since the mobilized carbon (C) was originally fixed from the atmosphere and to infer the turnover time of stem storage. Sites differed in concentration dynamics and overall δ(13) C, indicating different growing conditions. The absence of temporal trends for δ(13) C and Δ(14) C indicated sugar mobilization from a well-mixed pool with average Δ(14) C consistent with a mean turnover time (TT) of three to five years for this pool, with only minor differences between the sites. Sugar maple trees hence appear well buffered against single or even several years of negative plant C balance from environmental stress such as drought or repeated defoliation by insects. Manipulative investigations (e.g. starvation via girdling) combined with Δ(14) C measurements of this mobilized storage pool will provide further new insights into tree storage regulation and functioning. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  16. Seed size effects on the response of seedlings of Acacia asak (Forssk.) Willd to water stress

    International Nuclear Information System (INIS)

    El Atta, H.A.; Areef, I.M.; Ahmed, A.I.

    2016-01-01

    Dry tropical forests are characterized by unpredictable spells of drought and climate change. Saudi Arabia mostly falls within the arid zone and some few scattered areas fall in the semiarid zone mainly in the South Western region. Rainfall is sparse and with sporadic distribution. Drought is the most critical factor for restoration of the tree cover. Within a tree, seeds vary in size from large to small seeds. Although several researchers have studied the effect of within species variation in seed size on seedlings growth parameters, however there is a lack of knowledge regarding the effect of seed size on stress tolerance (Khurana and Singh 2000). We assumed that seedlings grown from different seed sizes from the same tree species may influence their response to water stress. Seeds of Acacia asak (Forssk.) Willd. were categorized into large, medium and small seeds on the basis of the seed weight. Seedlings from the three seed sizes were grown in potted soil and subjected to 5 levels of field water capacity (FC) (100, 75, 50, 25 and 15 percent) in the greenhouse. The Objective was to evaluate the response of seedling grown (from different seed sizes) to water stress and to understand the acclimation of seedlings to water stress. Water stress significantly reduced RWC, leaf area, and shoot length, fresh and dry weight. Significant correlations between growth parameters and water stress level were recorded. Seedlings from large seeds were heavier and comparatively less affected by drought compared to seedlings from smaller seeds. In all seedlings root length increased significantly and more biomass was allocated to roots than to shoots. However, at severe water stress (15 percent FC) no significant differences were reported between the three seedling categories. Therefore, raising of seedlings from large seeds is more appropriate for tree restoration programs under drought conditions. (author)

  17. Correlation of maple sap composition with bacterial and fungal communities determined by multiplex automated ribosomal intergenic spacer analysis (MARISA).

    Science.gov (United States)

    Filteau, Marie; Lagacé, Luc; LaPointe, Gisèle; Roy, Denis

    2011-08-01

    During collection, maple sap is contaminated by bacteria and fungi that subsequently colonize the tubing system. The bacterial microbiota has been more characterized than the fungal microbiota, but the impact of both components on maple sap quality remains unclear. This study focused on identifying bacterial and fungal members of maple sap and correlating microbiota composition with maple sap properties. A multiplex automated ribosomal intergenic spacer analysis (MARISA) method was developed to presumptively identify bacterial and fungal members of maple sap samples collected from 19 production sites during the tapping period. Results indicate that the fungal community of maple sap is mainly composed of yeast related to Mrakia sp., Mrakiella sp., Guehomyces pullulans, Cryptococcus victoriae and Williopsis saturnus. Mrakia, Mrakiella and Guehomyces peaks were identified in samples of all production sites and can be considered dominant and stable members of the fungal microbiota of maple sap. A multivariate analysis based on MARISA profiles and maple sap chemical composition data showed correlations between Candida sake, Janthinobacterium lividum, Williopsis sp., Leuconostoc mesenteroides, Mrakia sp., Rhodococcus sp., Pseudomonas tolaasii, G. pullulans and maple sap composition at different flow periods. This study provides new insights on the relationship between microbial community and maple sap quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Antioxidant activity, inhibition of nitric oxide overproduction, and in vitro antiproliferative effect of maple sap and syrup from Acer saccharum.

    Science.gov (United States)

    Legault, Jean; Girard-Lalancette, Karl; Grenon, Carole; Dussault, Catherine; Pichette, André

    2010-04-01

    Antioxidant activity, inhibition of nitric oxide (NO) overproduction, and antiproliferative effect of ethyl acetate extracts of maple sap and syrup from 30 producers were evaluated in regard to the period of harvest in three different regions of Québec, Canada. Oxygen radical absorbance capacity (ORAC) values of maple sap and syrup extracts are, respectively, 12 +/- 6 and 15 +/- 5 micromol of Trolox equivalents (TE)/mg. The antioxidant activity was also confirmed by a cell-based assay. The period of harvest has no statistically significant incidence on the antioxidant activity of both extracts. The antioxidant activity of pure maple syrup was also determined using the ORAC assay. Results indicate that the ORAC value of pure maple syrup (8 +/- 2 micromol of TE/mL) is lower than the ORAC value of blueberry juice (24 +/- 1 micromol of TE/mL) but comparable to the ORAC values of strawberry (10.7 +/- 0.4 micromol of TE/mL) and orange (10.8 +/- 0.5 micromol of TE/mL) juices. Maple sap and syrup extracts showed to significantly inhibit lipopolysaccharide-induced NO overproduction in RAW264.7 murine macrophages. Maple syrup extract was significantly more active than maple sap extract, suggesting that the transformation of maple sap into syrup increases NO inhibition activity. The highest NO inhibition induced by the maple syrup extracts was observed at the end of the season. Moreover, darker maple syrup was found to be more active than clear maple syrup, suggesting that some colored oxidized compounds could be responsible in part for the activity. Finally, maple syrup extracts (50% inhibitory concentration = 42 +/- 6 microg/mL) and pure maple syrup possess a selective in vitro antiproliferative activity against cancer cells.

  19. Determining sap sweetness in small sugar maple trees

    Science.gov (United States)

    Melvin R. Koelling

    1967-01-01

    Describes a technique based on the use of a hypodermic needle for determining sap-sugar concentrations in small trees. The technique is applicable to pot cultures in greenhouses and also, with the use of a movable shelter, to seedlings in nursery beds.

  20. Photosynthetic efficiency of Pedunculate oak seedlings under simulated water stress

    Directory of Open Access Journals (Sweden)

    Popović Zorica

    2010-01-01

    Full Text Available Photosynthetic performance of seedlings of Quercus robur exposed to short-term water stress in the laboratory conditions was assessed through the method of induced fluorometry. The substrate for seedlings was clayey loam, with the dominant texture fraction made of silt, followed by clay and fine sand, with total porosity 68.2%. Seedlings were separated in two groups: control (C (soil water regime in pots was maintained at the level of field water capacity and treated (water-stressed, WS (soil water regime was maintained in the range of wilting point and lentocapillary capacity. The photosynthetic efficiency was 0.642±0.25 and 0.522±0.024 (WS and C, respectively, which was mostly due to transplantation disturbances and sporadic leaf chlorosis. During the experiment Fv/Fm decreased in both groups (0.551±0.0100 and 0.427±0.018 in C and WS, respectively. Our results showed significant differences between stressed and control group, in regard to both observed parameters (Fv/Fm and T½. Photosynthetic efficiency of pedunculate oak seedlings was significantly affected by short-term water stress, but to a lesser extent than by sufficient watering.

  1. The effect of ectomycorrhizal fungi and bacteria on pine seedlings

    Directory of Open Access Journals (Sweden)

    Hanna Dahm

    2014-08-01

    Full Text Available The effect of ecomycorrhizal fungi (Hebelon crustuliniforme(Bull.: Fr. Quél. 5392 and Pisolithus tinctorius (Pers. Coker et Couch 5335 and bacteria (Bacillus polymyxa and Azospirillum brasilense. associated with mycorrhizas on the growth of pine seedligs was investigated. In addition the influence of bacteria on fungal biomass production and the relationship between ectomycorrhizal fungi and fungi pathogenic to root of pine seedlings were determined. In general, the shoot/root ratio was higher in plants inoculated with Hebeloma crustuliniforme and bacteria than in the control seedlings (grown only under sterile conditions. In non-sterile substrate the root/shoot ratio of the mycorrhizal seedlings was lower as compared to the control. Similar phenomenon was noted in plants inoculated with the mycorrhizal fungus Pisolithus tinetorius. The bacteria used as well as the time of introduction of these organisms into the cultures of mycorrhiza fungi affected the production of fungal biomass. Hebeloma crustuliniforme and Pisolithus tinctorius inhibited the growth of Rizoctonia solani and Fusarium oxysporum fungi pathogenic to pine seedlings.

  2. Stocking and structure for maximum growth in sugar maple selection stands.

    Science.gov (United States)

    Thomas R. Crow; Carl H. Tubbs; Rodney D. Jacobs; Robert R. Oberg

    1981-01-01

    The impacts of stocking, structure, and cutting cycle on basal area, cubic foot volume, board foot volume, and diameter growth are considered. Recommendations are provided for maximum growth in uneven-aged sugar maple stands.

  3. Paraformaldehyde pellet not necessary in vacuum-pumped maple sap system

    Science.gov (United States)

    H. Clay Smith; Carter B. Gibbs

    1970-01-01

    In a study of sugar maple sap collection through a vacuum-pumped plastic tubing system, yields were compared between tapholes in which paraformaldehyde pellets were used and tapholes without pellets, Use of the pellets did not increase yield.

  4. Bark thickness related to tree diameter in sugar maple (Acer saccharum Marsh.)

    Science.gov (United States)

    H. Clay Smith

    1969-01-01

    Bark thickness for sugar maple trees in Vermont was found to be related to tree diameter at breast height (d.b.h.). The relationship was positive-as the diameter increased, the bark thickness increased.

  5. A study on matrix assisted pulsed evaporation (MAPLE) of organic materials

    DEFF Research Database (Denmark)

    Matei, Andreea; Canulescu, Stela; Constantinescu, Catalin

    2012-01-01

    Organic films can be produced either by MAPLE or directly by PLD (Pulsed laser deposition). For a reasonable deposition rate of ng/cm2 per pulse for film production by MAPLE a fluence of 1-1.5 J/cm2 is required at the laser wavelength of 355 nm, while the fluence can be considerably lower at 248 nm....... At high fluence the deposition rate of proteins by MAPLE seems to decrease. The surface roughness is still an issue, but at low fluence it seems to be acceptable. The fragmentation rate increases with fluence, and seems to be less pronounced for MAPLE than for PLD. Also this issue is not yet resolved....

  6. The relationship between sap-flow rate and sap volume in dormant sugar maples

    Science.gov (United States)

    William J. Gabriel; Russell S. Walters; Donald W. Seegrist

    1972-01-01

    Sap-flow rate is closely correlated with the sap volume produced by dormant sugar maple trees (Acer saccharum Marsh.) and could be used in making phenotypic selections of trees for superior sap production.

  7. Growth response of four species of Eastern hardwood tree seedlings exposed to ozone, acidic precipitation, and sulfur dioxide

    International Nuclear Information System (INIS)

    Davis, D.D. Skelly, J.M.

    1992-01-01

    In 1987 a study was conducted in controlled environment chambers to determine the foliar sensitivity of tree seedlings of eight species to ozone and acidic precipitation, and to determine the influence of leaf position on symptom severity. Jensen and Dochinger conducted concurrent similar studies in Continuously Stirred Tank Reactor (CSTR) chambers with ten species of forest trees. Based on the results of these initial studies, four species representing a range in foliar sensitivity to ozone were chosen: black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.). These species were also chosen because of their ecological and/or commercial importance in Pennsylvania. Seedlings were exposed in growth chambers simulated acid rain. In addition acute exposures to sulfur dioxide were conducted in a regime based on unpublished monitoring data collected near coal-fired power plants. The objective of this study was to determine if the pollutant treatments influenced the growth and productivity of seedlings of these four species. This information will help researchers and foresters understand the role of air pollution in productivity of eastern forests

  8. PENGEMBANGAN MODEL PEMBELAJARAN KALKULUS BERBANTUAN KOMPUTER MELALUI PROGRAM MAPLE DI PROGRAM STUDI PENDIDIKAN MATEMATIKA

    OpenAIRE

    Parma Parma; Lalu Saparwadi

    2015-01-01

    The purpose of this research is the renewal of learning methods into calculus courses with modules of computer-assisted learning through maple. The products produced in this study is in the form of teaching materials in the form of calculus course lab guide through maple. With the resulting product of this research will be useful theoretically and practically. Theoretically, it is expected to result in the learning principles that can improve the quality of learning calculus, so as to enrich ...

  9. Flexural properties of laminated veneer lumber manufactured from ultrasonically rated red maple veneer : a pilot study.

    Science.gov (United States)

    Xiping Wang; Robert J. Ross; Brian K. Brashaw; Steven A. Verhey; John W. Forsman; John R. Erickson

    2003-01-01

    The study described in this report was conducted to examine the flexural properties of laminated veneer lumber (LVL) manufactured from red maple veneer. Ultrasonically rated veneer, which was peeled from low value red maple saw-logs, was fabricated into 1/2-in.-(1.3-cm-) and 2-in.-(5-cm-) thick LVL billets. The flexural properties of the billets and of corresponding...

  10. Growth of thin films of low molecular weight proteins by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Matei, Andreea; Schou, Jørgen; Constantinescu, C.

    2011-01-01

    Thin films of lysozyme and myoglobin grown by matrix assisted pulsed laser evaporation (MAPLE) from a water ice matrix have been investigated. The deposition rate of these two low molecular weight proteins (lysozyme: 14307 amu and myoglobin: 17083 amu) exhibits a maximum of about 1–2 ng/cm2 per....... The results for lysozyme demonstrate that the fragmentation rate of the proteins during the MAPLE process is not influenced by the pH of the water solution prior to freezing....

  11. Diffusion-weighted MRI of maple syrup urine disease encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Cavalleri, F.; Mavilla, L. [Servizio di Neuroradiologia, Azienda Ospedaliera Policlinico, Modena (Italy); Berardi, A.; Ferrari, F. [Servizio di Neonatologia, Azienda Ospedaliera Policlinico, Modena (Italy); Burlina, A.B. [Dipartimento di Pediatria, Azienda Ospedaliera, Universita di Padova, Padua (Italy)

    2002-06-01

    We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions. (orig.)

  12. Cranial computed tomography in maple syrup urine disease

    International Nuclear Information System (INIS)

    Irnberger, T.; Ploechl, E.; Rittinger, O.; Bachmann, C.; Pilz, P.; Walter, G.F.; Wendel, U.; Landeskrankenanstalten Salzburg; Bern Univ.; Landesnervenklinik Salzburg; Graz Univ.; Dudley Observatory, Albany, NY; Duesseldorf Univ.

    1986-01-01

    Cranial computed tomography in the initial stage of the intermediate phenotype of maple syrup urine disease (MSUD) demonstrates diffuse, symmetric hypodensities in white and grey matter, which show a complete return to normal after early introduction of an adequate protein-restrictive diet. If diagnosis of this disease is missed or delayed, progressive global (end-stage) atrophy will take place over several years. A decrease in density values correlates well with the total cerebral lipid and water content (closely related to myelinisation), whereas progression and grade of atrophy show a relationship with the severity of pathological white and grey matter changes that are not demonstrable with computed tomography but can be proven histologically. Analysis of both morphological parameters corresponds well with clinical-neurological outcome and therapeutic success. (orig.) [de

  13. Diffusion-weighted MRI of maple syrup urine disease encephalopathy

    International Nuclear Information System (INIS)

    Cavalleri, F.; Mavilla, L.; Berardi, A.; Ferrari, F.; Burlina, A.B.

    2002-01-01

    We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions. (orig.)

  14. EFFECTS OF CRUDE OIL POLLUTED SOIL ON THE SEEDLING GROWTH OF PENNISETUM GLAUCUM (L. R. BR.

    Directory of Open Access Journals (Sweden)

    Muhammad SHAFIQ

    2017-12-01

    Full Text Available Pollution by crude oil is an important environmental issue all around the world. Increase in oil pollution level in the environment produce toxic effects on flora and fauna of the region. The effects of different levels (0%, 5%, 10%, 15%, and 20% of crude oil polluted soil on the growth of pearl millet (Pennisetum glaucum were studied. The polluted soil affected the root, shoot length, seedling size, number of leaves and leaf area of P. glaucum. The significant (p<0.05 effects of polluted soil on fresh and dry weight of root, stem, leaves, and seedling of P. glaucum were also recorded. Leaf area, leaf number and total seedling dry weight were noticeably reduced in 10 and 15% polluted soil than control soil treatment. Principally, 20% crude oil polluted soil treatment exhibited highest percentage of decrease in most of the seedling growth parameters of P. glaucum than control. Hence, the effects on seedling growth parameters were increased with increasing levels of polluted soil. For most of the growth parameters, the mean values obtained were found higher for the control soil and progressively decreased from 5-20% crude oil polluted soils. The seedlings of P. glaucum were also tested for tolerance to polluted soil treatment. The results showed that the seedlings of P. glaucum showed high percentage of tolerance to low concentration (5% of polluted soil treatment as compared to control soil treatment (0%.

  15. Potential of fluorescence spectroscopy for the characterisation of maple syrup flavours.

    Science.gov (United States)

    Panneton, Bernard; Clément, Alain; Lagacé, Luc

    2013-10-01

    Maple syrup has high maket value. It is produced in North East America from the heat-evaporated sap of Acer saccharum Marshall. For marketing purposes, there is interest in defining its flavour profile in a consistent and repeatable manner. An experiment was undertaken to explore the potential of autofluorescence of maple syrup induced at 275 and 360 nm to characterise flavours. A mixed data factor analysis revealed two independent groups of variables. One represents early season woody and late season empyreumatic flavours. The other is related to off-flavour, confectionery and maple flavours. Maple and confectionery flavours are subtle, difficult to distinguish and opposed to off-flavour. There were clear relationships among the two groups and fluorescence profiles. For each of the five basic flavours, discriminant models based on partial least squares regressions were developed. For each sample of syrup, flavours combined to form flavour profiles, and the results from the five discriminant models were aggregated to reproduce these profiles. For excitation at 275 nm, the woody/off-flavour and confectionery/empyreumatic/maple flavour profiles were classified correctly 86 and 78% of the time (cross-validation) respectively. Induced autofluorescence spectra were shown to contain information related to maple syrup flavours. This fluorescence-flavour relationship is not considered quantitative yet, and further research avenues are proposed. © 2013 Society of Chemical Industry.

  16. Effect of canopy position on germination and seedling survival of epiphytic bromeliads in a Mexican humid montane forest.

    Science.gov (United States)

    Winkler, Manuela; Hülber, Karl; Hietz, Peter

    2005-05-01

    Seeds of epiphytes must land on branches with suitable substrates and microclimates to germinate and for the resulting seedlings to survive. It is important to understand the fate of seeds and seedlings in order to model populations, but this is often neglected when only established plants are included in analyses. The seeds of five bromeliad species were exposed to different canopy positions in a Mexican montane forest, and germination and early seedling survival were recorded. Additionally, the survival of naturally dispersed seedlings was monitored in a census over 2.5 years. Survival analysis, a procedure rarely used in plant ecology, was used to study the influence of branch characteristics and light on germination and seedling survival in natural and experimental populations. Experimental germination percentages ranged from 7.2 % in Tillandsia deppeana to 33.7 % in T. juncea, but the seeds of T. multicaulis largely failed to germinate. Twenty months after exposure between 3.5 and 9.4 % of the seedlings were still alive. There was no evidence that canopy position affected the probability of germination, but time to germination was shorter in less exposed canopy positions indicating that higher humidity accelerates germination. More experimental seedlings survived when canopy openness was high, whereas survival in census-seedlings was influenced by moss cover. While mortality decreased steadily with age in juveniles of the atmospheric Tillandsia, in the more mesomorphic Catopsis sessiliflora mortality increased dramatically in the dry season. Seedling mortality, rather than the failure to germinate, accounts for the differential distribution of epiphytes within the canopy studied. With few safe sites to germinate and high seedling mortality, changes of local climate may affect epiphyte populations primarily through their seedling stage.

  17. Physico-chemical changes in karkade (Hibiscus sabdariffa L.) seedlings responding to salt stress.

    Science.gov (United States)

    Galal, Abdelnasser

    2017-03-01

    Salinity is one of the major abiotic stress factors affecting series of morphological, physiological, metabolic and molecular changes in plant growth. The effect of different concentrations (0, 25, 50, 100 and 150 mM) of NaCl on the vegetative growth and some physiological parameters of karkade (Hibiscus sabdariffa var. sabdariffa) seedling were investigated. NaCl affected the germination rate, delayed emergence and retarded vegetative growth of seedlings. The length of seedling as well as the leaf area was significantly reduced. The fresh weight remained lower in NaCl treated seedlings compared to control. NaCl at 100 and 150 mM concentrations had significant effect on the dry matter contents of the treated seedlings. The chloroplast pigments in the treated seedlings were affected, suggesting that the NaCl had a significant effect on the chlorophyll and carotenoid biosynthesis. The results showed that the salt treatments induced an increase in proline concentration of the seedlings. The osmotic potential (ψs) of NaCl treated seedlings decreased with increasing NaCl concentrations. Salt treatments resulted in dramatic quantitative reduction in the total sterol percent compared with control ones. Salt stress resulted in increase and decrease of Na + and K + ions, respectively. NaCl salinity increased lipid peroxidation. SDS-PAGE was used to evaluate protein pattern after applying salt stress. High molecular weight proteins were intensified, while low molecular weight proteins were faint. NaCl at 100 and 150 mM concentration distinguished with new protein bands. Salt stress induced a new peroxidase bands and increased the band intensity, indicating the protective role of peroxidase enzyme.

  18. Changes in plasma glucose in Otsuka Long-Evans Tokushima Fatty rats after oral administration of maple syrup.

    Science.gov (United States)

    Nagai, Noriaki; Yamamoto, Tetsushi; Tanabe, Wataru; Ito, Yoshimasa; Kurabuchi, Satoshi; Mitamura, Kuniko; Taga, Atsushi

    2015-01-01

    We investigate whether maple syrup is a suitable sweetener in the management of type 2 diabetes using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The enhancement in plasma glucose (PG) and glucose absorption in the small intestine were lower after the oral administration of maple syrup than after sucrose administration in OLETF rats, and no significant differences were observed in insulin levels. These data suggested that maple syrup might inhibit the absorption of glucose from the small intestine and preventing the enhancement of PG in OLETF rats. Therefore, maple syrup might help in the prevention of type 2 diabetes.

  19. The Impact of Moss Species and Biomass on the Growth of Pinus sylvestris Tree Seedlings at Different Precipitation Frequencies

    Directory of Open Access Journals (Sweden)

    Babs M. Stuiver

    2014-08-01

    Full Text Available Boreal forests are characterized by an extensive moss layer, which may have both competitive and facilitative effects on forest regeneration. We conducted a greenhouse experiment to investigate how variation in moss species and biomass, in combination with precipitation frequency, affect Pinus sylvestris seedling growth. We found that moss species differed in their effects on seedling growth, and moss biomass had negative effects on seedlings, primarily when it reached maximal levels. When moss biomass was maximal, seedling biomass decreased, whereas height and above- relative to below-ground mass increased, due to competition for light. The effect that moss biomass had on seedling performance differed among the moss species. Hylocomium splendens and Polytrichum commune reduced seedling growth the most, likely because of their taller growth form. Seedlings were not adversely affected by Sphagnum girgensohnii and Pleurozium schreberi, possibly because they were not tall enough to compete for light and improved soil resource availability. Reduced precipitation frequency decreased the growth of all moss species, except P. commune, while it impaired the growth of seedlings only when they were grown with P. commune. Our findings suggest that changes in moss species and biomass, which can be altered by disturbance or climate change, can influence forest regeneration.

  20. Seedling recruitment of Colophospermum mopane on the Highveld ...

    African Journals Online (AJOL)

    Seedling recruitment of Colophospermum mopane on the Highveld of Zimbabwe: research note. ... Open areas with bare ground or sparse grass cover were favourable sites for seedling recruitment. Seedlings ... AJOL African Journals Online.

  1. Planning a new research reactor for AECL: The MAPLE-MTR concept

    International Nuclear Information System (INIS)

    Lee, A.G.; Lidstone, R.F.; Donnelly, J.V.

    1992-01-01

    AECL Research is assessing its needs and options for future irradiation research facilities. A planning team has been assembled to identify the irradiation requirements for AECL's research programs and compile options for satisfying the irradiation requirements. The planning team is formulating a set of criteria to evaluate the options and will recommend a plan for developing an appropriate research facility. Developing the MAPLE Materials Test Reactor (MAPLE-MTR) concept to satisfy AECL's irradiation requirements is one option under consideration by the planning team. AECL is undertaking this planning phase because the NRU reactor is 35 years old and many components are nearing the end of their design life. This reactor has been a versatile facility for proof testing CANDU components and fuel designs because the CANDU irradiation environment was simulated quite well. However, the CANDU design has matured and the irradiation requirements have changed. Future research programs will emphasize testing CANDU components near or beyond their design limits. To provide these irradiation conditions, the NRU reactor needs to be upgraded. Upgrading and refurbishing the NRU reactor is being considered, but the potentially large costs and regulatory uncertainties make this option very challenging. AECL is also developing the MAPLE-MTR concept as a potential replacement for the NRU reactor. The MAPLE-MTR concept starts from the recent MAPLE-X10 design and licensing experience and adapts this technology to satisfy the primary irradiation requirements of AECL's research programs. This approach should enable AECL to minimize the need for major advances in nuclear technology (e.g., fuel design, heat transfer). The preliminary considerations for developing the MAPLE-MTR concept are presented in this report. A summary of AECL's research programs is presented along with their irradiation requirements. This is followed by a description of safety criteria that need to be taken into

  2. Effects of 60Co γ-rays irradiation on germination and seedling growth of Hibiscus syriacus

    International Nuclear Information System (INIS)

    Li Xiufen; Wu Fulan; Zhang Deshun; Meng Zhennong; Cao Jiyun

    2009-01-01

    The seeds of Hibiscus syria cus were irradiated by 60 Co γ-rays at dose rate of 50 ∼ 500Gy/h for 0.5 and 1h, the seed germination rate and the seedling growth characters were surveyed. The results indicated that the seed germination was promoted when the absorbed dose was below 200Gy, and the seedling survival rate was increased when the dose was below 100Gy. The germination was inhibited, leaves and secondary roots were difficult to form, and the seedlings blasting occurred when the dose was over 200Gy. The dose rate affects the irradiation results. Absorbed dosed of 50 ∼ 100Gy were suggested for increasing seedling growth rate and 100 ∼ 200Gy were recommend for mutagenesis. (authors)

  3. Effects of water-soluble humic extract and biofertilizer on development of Callophyllum brasiliense seedlings

    Directory of Open Access Journals (Sweden)

    Jader Galba Busato

    2016-06-01

    Full Text Available The objective of this work was to evaluate the effects of water-soluble humic extract (EHSA, Hortbio® biofertilizer (HORT and both compounds combination (EHSA+HORT on vegetative growth, nutrient absorption and chlorophyll levels in guanandi (Callophyllum brasiliense seedlings. Isolated and combined additions of EHSA and HORT did not affect seedlings height, number of leaves, leaf and root dry matter and leaf area during early stages of seedling growth. However, HORT and EHSA+HORT treatments increased chlorophyll levels and total N content. Addition of HORT resulted in S, Zn, Mg, Mn and Cu increases in the seedlings leaves, while ESHA application increased K, Mg, S and B. P and Ca levels were not altered by the treatments, however, addition of EHSA and EHSA+HORT reduced significantly the absorption of Cu, Fe, Mn and Zn.

  4. MR diffusion imaging and MR spectroscopy of maple syrup urine disease during acute metabolic decompensation

    Energy Technology Data Exchange (ETDEWEB)

    Jan, Wajanat; Wang, Zhiyue J. [Department of Radiology, University of Pennsylvania School of Medicine, Children' s Hospital of Philadelphia, Pennsylvania (United States); Zimmerman, Robert A. [Department of Radiology, University of Pennsylvania School of Medicine, Children' s Hospital of Philadelphia, Pennsylvania (United States); Department of Radiology, Children' s Hospital of Philadelphia, 34th Street and Civic Center Boulevard, PA 19104, Philadelphia (United States); Berry, Gerard T.; Kaplan, Paige B.; Kaye, Edward M. [Department of Pediatrics, University of Pennsylvania School of Medicine, The Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States)

    2003-06-01

    Maple syrup urine disease (MSUD) is an inborn error of amino acid metabolism, which affects the brain tissue resulting in impairment or death if untreated. Imaging studies have shown reversible brain edema during acute metabolic decompensation. The purpose of this paper is to describe the diffusion-weighted imaging (DWI) and spectroscopy findings during metabolic decompensation and to assess the value of these findings in the prediction of patient outcome. Six patients with the diagnosis of MSUD underwent conventional MR imaging with DWI during acute presentation with metabolic decompensation. Spectroscopy with long TE was performed in four of the six patients. Follow-up examinations were performed after clinical and metabolic recovery. DWI demonstrated marked restriction of proton diffusion compatible with cytotoxic or intramyelinic sheath edema in the brainstem, basal ganglia, thalami, cerebellar and periventricular white matter and the cerebral cortex. This was accompanied by the presence of an abnormal branched-chain amino acids (BCAA) and branched-chain alpha-keto acids (BCKA) peak at 0.9 ppm as well as elevated lactate on proton spectroscopy in all four patients. The changes in all six patients were reversed with treatment without evidence of volume loss or persistent tissue damage. The presence of cytotoxic or intramyelinic edema as evidenced by restricted water diffusion on DWI, with the presence of lactate on spectroscopy, could imply imminent cell death. However, in the context of metabolic decompensation in MSUD, it appears that changes in cell osmolarity and metabolism can reverse completely after metabolic correction. (orig.)

  5. Effect of agitation rate on ethanol production from sugar maple hemicellulosic hydrolysate by Pichia stipitis.

    Science.gov (United States)

    Shupe, Alan M; Liu, Shijie

    2012-09-01

    Concentrated dilute acid hydrolysate was obtained from hot water extracts of Acer saccharum (sugar maple) and was fermented to ethanol by Pichia stipitis in a 1.3-L-benchtop bioreactor. The conditions under which the highest ethanol yield was achieved were when the air flow rate was set to 100 cm(3) and the agitation rate was set to 150 rpm resulting in an overall mass transfer coefficient (K(L)a) of 0.108 min(-1). A maximum ethanol concentration of 29.7 g/L was achieved after 120 h of fermentation; however, after 90 h of fermentation, the ethanol concentration was only slightly lower at 29.1 g/L with a yield of 0.39 g ethanol per gram of sugar consumed. Using the same air flow rate and adjusting the agitation rate resulted in lower ethanol yields of 0.25 g/g at 50 rpm and 0.30 g/g at 300 rpm. The time it takes to reach the maximum ethanol concentration was also affected by the agitation rate. The ethanol concentration continued to increase even after 130 h of fermentation when the agitation rate was set at 50 rpm, whereas the maximum ethanol concentration was reached after only 68.5 h at 300 rpm.

  6. MR diffusion imaging and MR spectroscopy of maple syrup urine disease during acute metabolic decompensation

    International Nuclear Information System (INIS)

    Jan, Wajanat; Wang, Zhiyue J.; Zimmerman, Robert A.; Berry, Gerard T.; Kaplan, Paige B.; Kaye, Edward M.

    2003-01-01

    Maple syrup urine disease (MSUD) is an inborn error of amino acid metabolism, which affects the brain tissue resulting in impairment or death if untreated. Imaging studies have shown reversible brain edema during acute metabolic decompensation. The purpose of this paper is to describe the diffusion-weighted imaging (DWI) and spectroscopy findings during metabolic decompensation and to assess the value of these findings in the prediction of patient outcome. Six patients with the diagnosis of MSUD underwent conventional MR imaging with DWI during acute presentation with metabolic decompensation. Spectroscopy with long TE was performed in four of the six patients. Follow-up examinations were performed after clinical and metabolic recovery. DWI demonstrated marked restriction of proton diffusion compatible with cytotoxic or intramyelinic sheath edema in the brainstem, basal ganglia, thalami, cerebellar and periventricular white matter and the cerebral cortex. This was accompanied by the presence of an abnormal branched-chain amino acids (BCAA) and branched-chain alpha-keto acids (BCKA) peak at 0.9 ppm as well as elevated lactate on proton spectroscopy in all four patients. The changes in all six patients were reversed with treatment without evidence of volume loss or persistent tissue damage. The presence of cytotoxic or intramyelinic edema as evidenced by restricted water diffusion on DWI, with the presence of lactate on spectroscopy, could imply imminent cell death. However, in the context of metabolic decompensation in MSUD, it appears that changes in cell osmolarity and metabolism can reverse completely after metabolic correction. (orig.)

  7. A Classic Case of Maple Syrup Urine Disease and a Novel Mutation in the BCKDHA Gene

    Directory of Open Access Journals (Sweden)

    Alieh Mirzaee

    2017-09-01

    Full Text Available Background: Maple syrup urine disease (MSUD is an inherited branched-chain amino acid metabolic disorder caused by the deficiency in the branched-chain alpha-keto acid dehydrogenase (BCKD complex. In MSUD, elevation of the branched-chain amino acids, such as alpha-keto acid and alpha-hydroxy acid, occurs due to the BCKDC gene deficiency, appearing in the blood, urine, and cerebrospinal fluid, which leads to neurological damage and mental retardation. MSUD phenotypically penetrates due to the mutations in the coding genes of four subunits of the BCKD complex, including the BCKDHA, BCKDHB, DBT, and DLD genes.Case report: We aimed to report the cases of three families whose children were affected by MSUD and presented with symptomatic features during the first week of birth, which were identified by mass spectrometry. DNA study was performed as a diagnosis panel containing four encoded BCKDC subunit genes.Conclusion: In the current study, DNA analysis and phenotypic manifestations indicated a novel mutation of c.143delT, p.L48Rfs*15 in the BCKDHA gene in a homozygous state, which is a causative mutation for the classic MSUD phenotype. Early diagnosis and neonatal screening are recommended for the accurate and effective treatment of this disease

  8. Early field performance of drought-stressed scots pine (pinus sylvestris l.) seedlings

    International Nuclear Information System (INIS)

    Kulac, S.; Clcek, E.; Tasdemir, U.

    2015-01-01

    Scots pine (Pinus sylvestris) has a large natural distribution throughout the world, including semi-arid areas of Turkey, where it is being used for afforestation. Determining the drought resistance of Scots pine provenances can increase the success of afforestation efforts in semi-arid regions. In the first stage of this study, water-stress treatments were applied to ten provenances of one-year-old Scots pine seedlings in their second vegetation period (between April and November). The diameter and height of the seedlings were evaluated in the nursery in order to determine their morphology. The four drought-stress treatments consisted of once-weekly irrigation (IR1), twice-weekly irrigation (IR2-Control), biweekly irrigation (IR3) and open field conditions (IR4). Later, the water-stressed seedlings were planted in a semi-arid district in Bayburt, Turkey, and their survival and growth performances were evaluated over a five-year period. The nursery study showed that drought stress and provenance as well as the interaction of the two significantly affected the morphological characteristics of the seedlings. Under water-stress conditions, the best growth performance was found in the Dokurcun, Degirmendere and Dirgine provenance seedlings. Water-stress and provenance factors and their interaction also affected the open field performance of the seedlings, where the Degirmendere, Dirgine and Dokurcun provenances again exhibited the best performance. Consequently, these Scots pine provenances can be recommended for afforestation sites having conditions similar to those of the study site. (author)

  9. Heat shock protein Hsp90-2 expression in the Arabidopsis thaliana seedlings under clinorotation

    Science.gov (United States)

    Kozeko, Liudmyla

    Heat shock proteins 90 kDa (Hsp90) are abundant under normal conditions and induced by stress. This family is distinguished from other chaperones in that most of its substrates are signal transduction proteins. Previously, we determined some time-dependent increase in the Hsp90 level in pea seedlings in response to simulated microgravity that indicated a stress-reaction. However, expression of the individual members of the Hsp90 family have specific pattern. The purpose of this study was to investigate possible alterations in the gene expression pattern of cytosolic Hsp90-2 in Arabidopsis thaliana seedlings under 2D-clinorotation. To obtain detailed expression pattern of the HSP90-2 genes we used seeds that provides a resource of loss-of-function mutations gene expression patterns via translational fusions with the reporter gene, GUS (a line N 166718, NASC). There were two variants of the experiment: 1) seedlings grew under clinorotation for 10, 12, 14 d; 2) seedlings grew in the stationary conditions for 10 d followed by clinorotation for 3 h -at 22o C and 16h light cycle. The seedlings grown in the stationary conditions were used as a control. GUS staining showed that HSP90-2 expression was regulated during seedling development and affected by clinorotation in the heterozygous mutant plants. In the homozygous for the mutation plants, HSP90-2 expression was stable during seedling development and not affected by clinorotation. GUS staining was observed in cotyledons, leaves and hypocotyls of the seedlings (especially intense in vascular bundles), indicating intensive cellular processes with participation of this chaperone. Possible pathways of influence of clinorotation on HSP90-2 expression are discussed.

  10. Diversity of seedling responses to drought

    NARCIS (Netherlands)

    Slot, M.; Poorter, L.

    2007-01-01

    Drought is an important seedling mortality agent in dry and moist tropical forests, and more severe and frequent droughts are predicted in the future. The effect of drought on leaf gas exchange and seedling survival was tested in a dry-down experiment with four tree species from dry and moist

  11. Responses of Tree Seedlings near the Alpine Treeline to Delayed Snowmelt and Reduced Sky Exposure

    Directory of Open Access Journals (Sweden)

    Maaike Y. Bader

    2017-12-01

    Full Text Available Earlier snowmelt changes spring stress exposure and growing-season length, possibly causing shifts in plant species dominance. If such shifts involve trees, this may lead to changes in treeline position. We hypothesized that earlier snowmelt would negatively affect the performance of tree seedlings near the treeline due to higher spring stress levels, but less so if seedlings were protected from the main stress factors of night frosts and excess solar radiation. We exposed seedlings of five European treeline tree species: Larix decidua, Picea abies, Pinus cembra, Pinus uncinata, and Sorbus aucuparia to two snow-cover treatments (early and late melting, with about two weeks difference combined with reduced sky exposure during the day (shading or night (night warming, repeated in two years, at a site about 200 m below the regional treeline elevation. Physiological stress levels (as indicated by lower Fv/Fm in the first weeks after emergence from snow were higher in early-emerging seedlings. As expected, shade reduced stress, but contrary to expectation, night warming did not. However, early- and late-emerging seedlings did not differ overall in their growth or survival, and the interaction with shading was inconsistent between years. Overall, shading had the strongest effect, decreasing stress levels and mortality (in the early-emerging seedlings only, but also growth. A two-week difference in snow-cover duration did not strongly affect the seedlings, although even smaller differences have been shown to affect productivity in alpine and arctic tundra vegetation. Still, snowmelt timing cannot be discarded as important for regeneration in subalpine conditions, because (1 it is likely more critical in very snow-rich or snow-poor mountains or landscape positions; and (2 it can change (subalpine vegetation phenology and productivity, thereby affecting plant interactions, an aspect that should be considered in future studies.

  12. Nutrients, Antioxidant Capacity and Safety of Hot Water Extract from Sugar Maple (Acer saccharum M.) and Red Maple (Acer rubrum L.) Bark.

    Science.gov (United States)

    Bhatta, Sagar; Ratti, Cristina; Poubelle, Patrice E; Stevanovic, Tatjana

    2018-03-01

    Sugar maple (Acer saccharum M.) and red maple (Acer rubrum L.) barks were treated with hot water to extract nutrients in order to explore, for the first time, its potential as safe dietary antioxidants. The organic and inorganic nutrients of these extracts, as well as their safety on human PLB-985 cells differentiated into neutrophils-like cells, were determined. Proximate analysis showed that both bark extracts were low in moisture and fat. Sugar maple bark extract (SM-BX) showed crude protein and ash content higher than those found in red maple bark extract (RM-BX). In addition, SM-BX had total sugars higher than those evaluated in RM-BX, while complex sugars (oligo- and/or poly-saccharides) were similarly abundant in both bark extracts. Furthermore, SM-BX demonstrated a wide array of vital minerals (K, Ca, Mg, P, Na, Fe and Cu) in quantity larger than that evaluated in RM-BX, whereas RM-BX have Zn and Mn levels higher than those found in SM-BX. Phytochemical analyses showed that RM-BX exhibited total phenolic and flavonoid contents higher than those measured in SM-BX. Consequently, RM-BX presented an antioxidant activity higher than that of SM-BX: 2.85-fold ABTS radical cation scavenging capacity and 1.9-fold oxygen radical absorbance capacity. Finally, RM-BX and SM-BX were greatly safe since, at concentration up to 100 μg/ml, they did not modify the viability of neutrophils as determined by flow-cytometry assay using Annexin V-FITC/Propidum Iodide as markers. In conclusion, our in vitro studies indicate that both red and sugar maple bark extracts have a real potential as food additives.

  13. RIR-MAPLE deposition of conjugated polymers and hybrid nanocomposites for application to optoelectronic devices

    International Nuclear Information System (INIS)

    Stiff-Roberts, Adrienne D.; Pate, Ryan; McCormick, Ryan; Lantz, Kevin R.

    2012-01-01

    Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) is a variation of pulsed laser deposition that is useful for organic-based thin films because it reduces material degradation by selective absorption of infrared radiation in the host matrix. A unique emulsion-based RIR-MAPLE approach has been developed that reduces substrate exposure to solvents and provides controlled and repeatable organic thin film deposition. In order to establish emulsion-based RIR-MAPLE as a preferred deposition technique for conjugated polymer or hybrid nanocomposite optoelectronic devices, studies have been conducted to demonstrate the value added by the approach in comparison to traditional solution-based deposition techniques, and this work will be reviewed. The control of hybrid nanocomposite thin film deposition, and the photoconductivity in such materials deposited using emulsion-based RIR-MAPLE, will also be reviewed. The overall result of these studies is the demonstration of emulsion-based RIR-MAPLE as a viable option for the fabrication of conjugated polymer and hybrid nanocomposite optoelectronic devices that could yield improved device performance.

  14. Regional growth decline of sugar maple (Acer saccharum) and its potential causes

    Science.gov (United States)

    Bishop, Daniel A.; Beier, Colin M.; Pederson, Neil; Lawrence, Gregory B.; Stella, John C; Sullivan, Timothy J.

    2015-01-01

    Sugar maple (Acer saccharum Marsh) has experienced poor vigor, regeneration failure, and elevated mortality across much of its range, but there has been relatively little attention to its growth rates. Based on a well-replicated dendrochronological network of range-centered populations in the Adirondack Mountains (USA), which encompassed a wide gradient of soil fertility, we observed that the majority of sugar maple trees exhibited negative growth trends in the last several decades, regardless of age, diameter, or soil fertility. Such growth patterns were unexpected, given recent warming and increased moisture availability, as well as reduced acidic deposition, which should have favored growth. Mean basal area increment was greater on base-rich soils, but these stands also experienced sharp reductions in growth. Growth sensitivity of sugar maple to temperature and precipitation was non-stationary during the last century, with overall weaker relationships than expected. Given the favorable competitive status and age structure of the Adirondack sugar maple populations sampled, evidence of widespread growth reductions raises concern over this ecologically and economically important tree. Further study will be needed to establish whether growth declines of sugar maple are occurring more widely across its range.

  15. Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest.

    Science.gov (United States)

    Halman, Joshua M; Schaberg, Paul G; Hawley, Gary J; Pardo, Linda H; Fahey, Timothy J

    2013-11-01

    Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature sugar maple physiology were evaluated at the Hubbard Brook Experimental Forest (Thornton, NH, USA) to assess remediation (Ca addition) or exacerbation (Al addition) of current acidified conditions. Fine root cation concentrations and membrane integrity, carbon (C) allocation, foliar cation concentrations and antioxidant activity, foliar response to a spring freezing event and reproductive ability (flowering, seed quantity, filled seed and seed germination) were evaluated for dominant sugar maple trees in a replicated plot study. Root damage and foliar antioxidant activity were highest in Al-treated trees, while growth-associated C, foliar re-flush following a spring frost and reproductive ability were highest in Ca-treated trees. In general, we found that trees on Ca-treated plots preferentially used C resources for growth and reproductive processes, whereas Al-treated trees devoted C to defense-based processes. Similarities between Al-treated and control trees were observed for foliar cation concentrations, C partitioning and seed production, suggesting that sugar maples growing in native forests may be more stressed than previously perceived. Our experiment suggests that disruption of the balance of Ca and Al in sugar maples by acid deposition continues to be an important driver of tree health.

  16. Maple Syrup Urine Disease Complicated with Kyphoscoliosis and Myelopathy

    Directory of Open Access Journals (Sweden)

    Jia-Woei Hou

    2016-10-01

    Full Text Available Maple syrup urine disease (MSUD is an autosomal recessive aminoacidopathy secondary to an enzyme defect in the catabolic pathway of the branched-chain amino acids (BCAAs: leucine, isoleucine, and valine. Accumulation of their corresponding keto-acids leads to encephalopathy if not treated in time. A newborn male patient was suspected to have MSUD after tandem mass study when he presented symptoms and signs suggestive neonatal sepsis, anemia, and diarrhea. Food restriction of BCAAs was started; however, acrodermatitis enteropathica-like skin eruptions occurred at age 2 months. The skin rashes resolved after adding BCAAs and adjusting the infant formula. At age 7 months, he suffered from recurrent skin lesions, zinc deficiency, osteoporosis, and kyphosis of the thoracic spine with acute angulation over the T11-T12 level associated with spinal compression and myelopathy. After supplementation of zinc products and pamidronate, skin lesions and osteopenia improved gradually. Direct sequencing of the DBT gene showed a compound heterozygous mutation [4.7 kb deletion and c.650-651insT (L217F or L217fsX223]. It is unusual that neurodegeneration still developed in this patient despite diet restriction. Additionally, brain and spinal magnetic resonance imaging, bone mineral density study, and monitoring of zinc status are suggested in MSUD patients.

  17. MAPLE-X10 reactor digital control system

    International Nuclear Information System (INIS)

    Deverno, M.T.; Hinds, H.W.

    1991-10-01

    The MAPLE-X10 reactor, currently under construction at the Chalk River Laboratories of Atomic Energy of Canada Limited, is a 10 MW t , pool-type, light-water reactor. It will be used for radioisotope production and silicon neutron transmutation doping. The reactor is controlled by a Digital Control System (DCS) and protected against abnormal process events by two independent safety systems. The DCS is an integrated control system used to regulate the reactor power and process systems. The safety philosophy for the control system is to minimize unsafe events arising from system failures and operational errors. this is achieved through redundancy, fail-safe design, automatic fault detection, and the selection of highly reliable components. The DCS provides both computer-controlled reactor regulation from the shutdown state to full power and automated reactor shutdown if safe limits are exceeded or critical sensors malfunction. The use of commercially available hardware with enhanced quality assurance makes the system cost effective while providing a high degree of reliability

  18. Stable-carbon isotopic composition of maple sap and foliage

    International Nuclear Information System (INIS)

    Leavitt, S.W.; Long, A.

    1985-01-01

    The 13 C/ 12 C ratios of Acer grandidentatum sap sugar collected during the dormant period are compared to those of buds, leaves, and wood developed over the following growing season. As the primary carbon source for cellulose manufacture at initiation of annual growth in deciduous trees, sap sucrose would be expected to have an isotopic composition similar to first-formed cellulose. Although constancy in concentration and 13 C/ 12 C ratios of the maple sap sugar suggests any gains or losses (e.g. to maintenance metabolism) do not appreciably alter composition, the 13 C/ 12 C ratios of cellulose of the enlarging buds in the spring are quite distinct from those of the sap sugar, seemingly precluding a simple direct biochemical pathway of sap sucrose→glucose→cellulose in favor of a more complex pathway with greater likelihood of isotopic fractionation. The 13 C/ 12 C ratios of the leaves and in the growth ring were initially similar to the sap sugar but decreased steadily over the growing season. (author)

  19. Allelopathic activity of Leonurus siribicus L. on seed germination and seedling growth of wheat and identification of 4- hydroxy benzoic acid as an allelochemical by chromatography

    International Nuclear Information System (INIS)

    Sayed, M. A.; Imam, R.; Siddiqui, M.N.

    2016-01-01

    The aim of this study was to investigate the allelopathic effects of L. siribicus extract on seed germination and seedlings growth of wheat as well as to identify potential allelochemical. The different concentration (5, 10 and 15%) of aqueous extract were applied during the time of sowing and at 5 days after sowing of wheat seed. L. siribicus extract showed concentration and time - depending activity. Different concentration of aqueous extract inhibited seed germination, seedlings growth, when extracts were applied during the time of seed sowing. The stimulatory effect of seedlings growth were found for 5 % aqueous extract, in contrast 10 and 15% extract inhibited seedlings growth, when extracts were applied at 5 days after sowing. Apart from, 4-hydroxy benzoic acids affected seedlings growth irrespective of application time. The weight of dry matter of wheat seedlings were increased for 5% than 10 and 15% extracts. Thin layer chromatography suggested that the presence of 4-hydroxy benzoic acid including other allelopathic and growth regulatory compounds inhibited germination and seedlings growth. Mineral composition was determined and its might have some stimulatory effect on seedlings growth. It was interesting that 5% extract inhibited germination and seedlings growth, when it was applied during the time of seed sowing, but stimulated seedling growth, when it was applied at 5 days after sowing. The extract of this plants can be used either for bioherbicide as well as growth stimulatory agents for the organic farming system. To find out molecular mechanism behind it, further research is to be done. (author)

  20. Safety-related parameters for the MAPLE research reactor and a comparison with the IAEA generic 10-MW research reactor

    International Nuclear Information System (INIS)

    Carlson, P.A.; Lee, A.G.; Smith, H.J.; Ellis, R.J.

    1989-07-01

    A summary is presented of some of the principle safety-related physics parameters for the MAPLE Research Reactor, and a comparison with the IAEA Generic 10-MW Reactor is given. This provides a means to assess the operating conditions and fuelling requirements for safe operation of the MAPLE Research Reactor under accepted standards

  1. Hypoglycin A Concentrations in Maple Tree Species in the Netherlands and the Occurrence of Atypical Myopathy in Horses

    NARCIS (Netherlands)

    Westermann, C.M.; Van Leeuwen, Robbert; Van Raamsdonk, L.W.D.; Mol, H.G.J.

    BACKGROUND: Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees. HYPOTHESIS/OBJECTIVES: To measure

  2. Hypoglycin A Concentrations in Maple Tree Species in the Netherlands and the Occurrence of Atypical Myopathy in Horses

    NARCIS (Netherlands)

    Westermann, C.M.; Leeuwen, van R.; Raamsdonk, van L.W.D.; Mol, H.G.J.

    2016-01-01

    Background: Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees. Hypothesis/Objectives: To

  3. A Profile of Lake States Maple Syrup Producers and Their Attitudes and Responses to Economic, Social, Ecological and Climate Challenges

    Science.gov (United States)

    Stephanie A. Snyder; Michael A. Kilgore; Marla R. Emery; Marissa. Schmitz

    2018-01-01

    Maple syrup is an iconic as well as economically and culturally important non-timber forest product in North America. The economic benefits derived from maple syrup production are substantial. In 2016, the U.S. produced 4.2 million gallons of syrup worth an estimated $147 million (USDA, 2017b). In addition, sugaring provides many with a deep, personal connection to...

  4. The Changing Colors of Maple Hills: Intersections of Culture, Race, Language, and Exceptionality in a Rural Farming Community

    Science.gov (United States)

    Scanlan, Martin

    2016-01-01

    This case describes Maple Hills Elementary, a K-8 school in a rural farming community of the Midwest. As a community, Maple Hills has historically experienced a narrow range of diversity across race, ethnicity, language, and religion. Residents have predominantly been White, with German and English heritage, speak English as a mother tongue, and…

  5. 75 FR 57016 - Maple Analytics, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...

    Science.gov (United States)

    2010-09-17

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER10-2541-000] Maple Analytics, LLC; Supplemental Notice That Initial Market- Based Rate Filing Includes Request for Blanket... proceeding of Maple Analytics, LLC's application for market-based rate authority, with an accompanying rate...

  6. Bacillus amyloliquefaciens levansucrase-catalyzed the synthesis of fructooligosaccharides, oligolevan and levan in maple syrup-based reaction systems.

    Science.gov (United States)

    Li, Mengxi; Seo, Sooyoun; Karboune, Salwa

    2015-11-20

    Maple syrups with selected degree Brix (°Bx) (15, 30, 60) were investigated as reaction systems for levansucrase from Bacillus amyloliquefaciens. The enzymatic conversion of sucrose present in the maple syrup and the production of the transfructosylation products were assessed over a time course of 48h. At 30°C, the use of maple syrup 30°Bx led to the highest levansucrase activity (427.53μmol/mg protein/min), while maple syrup 66°Bx led to the highest converted sucrose concentration (1.53M). In maple syrup 30°Bx, oligolevans (1080%). In maple syrup 66°Bx, the most abundant products were oligolevans at 30°C and levans (DP≥30) at 8°C. The acceptor specificity study revealed the ability of B. amyloliquefaciens levansucrase to synthesize a variety of hetero-fructooligosaccharides (FOSs) in maple syrups 15°Bx and 30°Bx enriched with various disaccharides, with lactose being the preferred fructosyl acceptor. The current study is the first to investigate maple-syrup-based reaction systems for the synthesis of FOSs/oligolevans/levans. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  8. Production and development of eucalyptus seedlings in function of doses of phosphorus

    Directory of Open Access Journals (Sweden)

    José Henrique Tertulino Rocha

    2013-12-01

    Full Text Available This study evaluated the effect of phosphorus (P on the survival in the nursery and early development in the field of clonal Eucalyptus urophylla x Eucalyptus grandis seedlings. The experimental design was completely randomized with four treatments and five replicates of 30 plants per replicate. At the end of the cycle (90 days, 15 seedlings were used for determining the dry matter accumulation and nutrient concentration in the shoot. The rest was planted in the field to determine the percentage of survival and early development. The treatments consisted of four doses of P fertilization (0.0, 1.3, 2.6 and 5.2 mg plant-1. To obtain high quality seedlings in conditions similar to this experiment it is required doses of P in the range from 3.6 to 3.8 mg plant-1. Doses greater than 4 mg plant-1 affect the development and quality of eucalyptus seedlings. An adequate phosphorus fertilization of eucalyptus seedlings increase, by about 30%, the percentage of surviving seedlings in the field.

  9. Seedling emergence of an array of Campomanesia adamantium (Cambess. O. Berg, under different conditions

    Directory of Open Access Journals (Sweden)

    Kaila Ressel

    2014-12-01

    Full Text Available Seedling emergence of an array of Campomanesia adamantium (Cambess. O. Berg, under different conditions. Campomanesia adamantium are shrubs with berries that are yellow when ripe, with sweet, aromatic and juicy pulp. The fruits are very appreciated by the Midwestern Brazilian population because, beyond the economic potential, gabirobeiras have important ecological and medicinal applications. The few reports concerning methods of C. adamantium propagation demonstrate varied responses of the germination process, and variation sometimes occurs for seeds planted under similar conditions. The objective of this study was to evaluate the inluence of different substrates and seed pulp extraction methods on seedling emergence of C. adamantium. Seeds were collected from a single individual. The experiment tested four methods of seed pulp extraction: a Control: seeds sown with pulp, b seeds whose pulp was mechanically removed by friction using fine sawdust, c seeds whose pulp was removed by washing in running water; d seeds with pulp soaked for 24 h. Four different substrates per pulp extraction type were then used for planting: 1 Vermiculite; 2 Plantmax ®; 3 Tri-Mix ®, 4 washed medium-grain sand. Sand was the substrate that produced the best result for seedling emergence, however there were no significant differences in seedling emergence between seed processing methods. The presence of seed pulp did not impact percent seedling emergence, nor did it affect average time or speed of seedling emergence.

  10. Use of rice seedlings to estimate uptake of radiocesium from soil to plants in Fukushima Prefecture

    International Nuclear Information System (INIS)

    Fujimura, Shigeto; Suzuki, Yasukazu; Ohno, Takeshi

    2013-01-01

    The uptake of radiocesium to plants from the soil is affected by many environmental factors, and it is difficult to determine the contribution of uptake among these factors. In addition, these environmental factors should be investigated independently for each field. The aim of this study was to develop a practical and simple method for the estimate of uptake of radiocesium from soil to plants. Rice seedlings were used to estimate the root uptake of radiocesium from seven different soils. To confirm that the seedlings were the effective indicator, the concentration of "1"3"7Cs in the seedlings was compared with that in brown rice and sunflower. The seedlings were cultivated for a week from germination in a phytotron and the concentrations of "1"3"7Cs in the seedlings above ground were determined. To obtain brown rice and sunflower, rice and sunflower were cultivated either in a pot (1/5000 a Wagner pot, 4000 cm"3) placed in a glasshouse or in a paddy field in Fukushima prefecture for two to four months. The concentration of "1"3"7Cs in the rice seedlings ranged from 150 to 1900 Bq kg"-"1, and that in brown rice and sunflower ranged from 2 to 880 Bq kg"-"1 and from 580 to 3900 Bq kg"-"1, respectively. The Spearman's rank correlation coefficient between the measured concentration of "1"3"7Cs in rice seedlings and the measured concentration of "1"3"7Cs in brown rice and sunflower was 1.0 (p < 0.001 and p = 0.09, respectively). This suggests that the use of rice seedlings in this experiment over a period of two weeks provides an effective indicator for the uptake of "1"3"7Cs from soil to plants over a longer period of time. (author)

  11. Use of rice seedlings to estimate uptake of radiocesium from soil to plants in Fukushima Prefecture

    International Nuclear Information System (INIS)

    Fujimura, Shigeto; Suzuki, Yasukazu; Ohno, Takeshi

    2012-01-01

    The uptake of radiocesium to plants from the soil is affected by many environmental factors, and it is difficult to determine the contribution of uptake among these factors. In addition, these environmental factors should be investigated independently for each field. The aim of this study was to develop a practical and simple method for the estimate of uptake of radiocesium from soil to plants. Rice seedlings were used to estimate the root uptake of radiocesium from seven different soils. To confirm that the seedlings were the effective indicator, the concentration of 137 Cs in the seedlings was compared with that in brown rice and sunflower. The seedlings were cultivated for a week from germination in a phytotron and the concentrations of 137 Cs in the seedlings above ground were determined. To obtain brown rice and sunflower, rice and sunflower were cultivated either in a pot (1/5000 a Wagner pot, 4000 cm 3 ) placed in a glasshouse or in a paddy field in Fukushima prefecture for two to four months. The concentration of 137 Cs in the rice seedlings ranged from 150 to 1900 Bq kg -1 , and that in brown rice and sunflower ranged from 2 to 880 Bq kg -1 and from 580 to 3900 Bq kg -1 , respectively. The Spearman's rank correlation coefficient between the measured concentration of 137 Cs in rice seedlings and the measured concentration of 137 Cs in brown rice and sunflower was 1.0 (p < 0.001 and p = 0.09, respectively). This suggests that the use of rice seedlings in this experiment over a period of two weeks provides an effective indicator for the uptake of 137 Cs from soil to plants over a longer period of time. (author)

  12. Cadmium and zinc toxicity in white pine, red maple, and Norway spruce

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, C.D.; Fretz, T.A.

    1977-01-01

    Excessive accumulation of Cd or Zn in white pine (Pinus strobus L.), red maple (Acer rubrum L.), and Norway spruce (Picea abies L.), resulted in reduced root initiation, poor development of root laterals, chlorosis, dwarfism, early leaf drop, wilting, and necrosis of current season's growth. Positive correlations existed between nutrient culture levels and tissue accumulation when plants were grown in sand. White pine seddlings accumulated more Cd and Zn than either red maple or Norway spurce when compared in similar experiments. White pine appeared to be more tolerant of Cd and Zn accumulation than either red maple or Norway spruce since visual phytotoxicity symptoms were observed only at the higher: 1 treatment levels. Accumulation of Cd and Zn from a medium of 2 sand:1 soil:1 perlite by volume was also observed.

  13. THE USE OF GAP AND MAPLE SOFTWARE IN TEACHING GROUP THEORY

    Directory of Open Access Journals (Sweden)

    Ema Carnia

    2017-12-01

    Full Text Available Algebra is a subject that must be taken by all students in an undergraduate mathematics study program. However, teachers are often faced with students’ difficulties in understanding some of the concepts that are contained in this subject. The tendency of students who generally follow the development of technology can be seen as an opportunity to overcome these problems. Several studies have been undertaken regarding the use of computers in teaching abstract algebra. This paper will detail a comparison between GAP and Maple software as a commonly used software and constantly updated until today. The paper focused on the concept of group theory as the basis for understanding the course of abstract algebra. Result shows that in terms of visualization, Maple is better than GAP but in terms of substance GAP is better than Maple.

  14. Skin Lesions Associated with Dietary Management of Maple Syrup Urine Disease: a Case Report

    Directory of Open Access Journals (Sweden)

    Kazandjieva Jana

    2015-12-01

    Full Text Available Leucinosis (maple syrup urine disease - MSUD is an inherited aminoacidopathy and organic aciduria caused by severe enzyme defect in the metabolic pathway of amino acids: leucine, isoleucine, and valine. The classical variant of the disease is characterized by accumulation of both amino and α-keto acids, particulary the most toxic rapid elevation of circulating leucine and its ketoacid, α-ketoisocaproate, which cause encephalopathy and life-threatening brain swelling. However, patients with the most severe form, classical maple syrup urine disease, may appear normal at birth, but develop acute metabolic decompensation within the first weeks of life with typical symptoms: poor feeding, vomiting, poor weight gain, somnolence and burnt sugar-smelling urine, reminiscent of maple syrup. Early diagnosis and dietary intervention improve the patient’s condition, prevent severe complications, and may allow normal intellectual development.

  15. PERAWATAN GIGI PADA ANAK DENGAN MAPLE SYRUP URINE DISEASE (LAPORAN KASUS

    Directory of Open Access Journals (Sweden)

    Tri Fajari

    2015-07-01

    Full Text Available Maple Syrup Urine Disease is a disparity of leusin decarboxilation, and isoleusin of valin defect that is synthesized with complex enzyme systems. It is a rare disease and represents disparity. In some cases can generate ketosis that grows according to health change and can cause comma. Dental treatment of a child with Maple Syrup Urine Disease was not clearly mentioned, there is only a factor such as infection, which is very dangerous at any age, and can generate irregular metabolism. Dental treatment of a child with Maple Syrup Urine Disease accompanied by mental retardation must be done continuously to avoid infection that can result in the death of the patients.

  16. Morphological parameters of the norway maple small undergrowthin forests of the Novgorod-Sivers’k Polissia

    Directory of Open Access Journals (Sweden)

    V. G. Skliar

    2012-02-01

    Full Text Available The size characteristics of the Norway maple small undergrowth in different association groups of the forests of Novgorod-Sivers’k Polissia are аnalyzed. As the trophicity of soil increases the values of static metric and dynamic morphoparameters of the undergrowth upsurge. And on the contrary, the values reduced with the growth of the forest overstory density and the projective cover of the herb-shrub layer. It is shown that in different plant communities the Norway maple undergrowth is characterised by specific morphological structure. The communal habitat of the group of Querceta convallariosa associations conforms with the parameters of ecocoenotical optimum, which conditions are most favourable for successful growth of the maple young generation.

  17. Red Maple (Acer rubrum) Aerial Parts as a Source of Bioactive Phenolics.

    Science.gov (United States)

    Zhang, Yan; Ma, Hang; Yuan, Tao; Seeram, Navindra P

    2015-08-01

    The bark and stems of red maple (Acer rubrum) are reported to contain bioactive phenolics but its aerial parts, namely, flowers and leaves, remain largely unexplored. This is unfortunate considering that various parts of the red maple were used for traditional medicinal purposes by the indigenous peoples of eastern North America, where this species is found. Herein, we report the identification of twenty-five (1-25) phenolics, including two new galloyl derivatives (1 and 2), from red maple flowers and leaves. Of these, ten compounds (1-10), including the new compounds, were isolated and identified by NMR and HRESIMS data while the remaining fifteen compounds (11-25) were identified by HPLC-DAD analyses (by comparison with chemical standards). The isolates (1-10), along with the clinical drug, acarbose, were evaluated for their alpha-glucosidase enzyme inhibitory activities.

  18. Medical isotope shortage 2009-2010 and future options NRU, SLOWPOKE and MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Hilborn, J. [Deep River, Ontario (Canada)

    2013-07-01

    The 15 month shutdown of NRU and the unexpected termination of the AECL/Nordion MAPLE project caused a world-wide shortage of medical isotopes. After the recent repair of NRU, AECL is confident that it could continue operating safely and reliably as a multi-purpose reactor until 2021 or longer. There is convincing evidence that the restoration of the MAPLE reactors is technically feasible, but it is highly improbable that a 10 MW MAPLE production reactor can ever be cost-effective. However, conversion of the present 10 MW reactors to 3 MW, without major changes to the structural hardware, warrants serious consideration. Finally, even the 20 kW SLOWPOKE reactor could produce useful quantities of Mo-99. If the present fuel rods were replaced with a small tank containing a solution of low-enriched uranyl sulphate in water, three of these liquid core reactors could supply all of Canada. (author)

  19. Characterization of MAPLE deposited WO3 thin films for electrochromic applications

    Science.gov (United States)

    Boyadjiev, S. I.; Stefan, N.; Szilágyi, I. M.; Mihailescu, N.; Visan, A.; Mihailescu, I. N.; Stan, G. E.; Besleaga, C.; Iliev, M. T.; Gesheva, K. A.

    2017-01-01

    Tungsten trioxide (WO3) is a widely studied material for electrochromic applications. The structure, morphology and optical properties of WO3 thin films, grown by matrix assisted pulsed laser evaporation (MAPLE) from monoclinic WO3 nano-sized particles, were investigated for their possible application as electrochromic layers. A KrF* excimer (λ=248 nm, ζFWHM=25 ns) laser source was used in all experiments. The MAPLE deposited WO3 thin films were studied by atomic force microscopy (AFM), grazing incidence X-ray diffraction (GIXRD) and Fourier transform infrared spectroscopy (FTIR). Cyclic voltammetry measurements were also performed, and the coloring and bleaching were observed. The morpho-structural investigations disclosed the synthesis of single-phase monoclinic WO3 films consisting of crystalline nano-grains embedded in an amorphous matrix. All thin films showed good electrochromic properties, thus validating application of the MAPLE deposition technique for the further development of electrochromic devices.

  20. Characterization of MAPLE deposited WO3 thin films for electrochromic applications

    International Nuclear Information System (INIS)

    Boyadjiev, S I; Iliev, M T; Stefan, N; Mihailescu, N; Visan, A; Mihailescu, I N; Szilágyi, I M; Stan, G E; Besleaga, C; Gesheva, K A

    2017-01-01

    Tungsten trioxide (WO 3 ) is a widely studied material for electrochromic applications. The structure, morphology and optical properties of WO 3 thin films, grown by matrix assisted pulsed laser evaporation (MAPLE) from monoclinic WO 3 nano-sized particles, were investigated for their possible application as electrochromic layers. A KrF* excimer (λ=248 nm, ζ FWHM =25 ns) laser source was used in all experiments. The MAPLE deposited WO 3 thin films were studied by atomic force microscopy (AFM), grazing incidence X-ray diffraction (GIXRD) and Fourier transform infrared spectroscopy (FTIR). Cyclic voltammetry measurements were also performed, and the coloring and bleaching were observed. The morpho-structural investigations disclosed the synthesis of single-phase monoclinic WO 3 films consisting of crystalline nano-grains embedded in an amorphous matrix. All thin films showed good electrochromic properties, thus validating application of the MAPLE deposition technique for the further development of electrochromic devices. (paper)

  1. Medical isotope shortage 2009-2010 and future options NRU, SLOWPOKE and MAPLE

    International Nuclear Information System (INIS)

    Hilborn, J.

    2013-01-01

    The 15 month shutdown of NRU and the unexpected termination of the AECL/Nordion MAPLE project caused a world-wide shortage of medical isotopes. After the recent repair of NRU, AECL is confident that it could continue operating safely and reliably as a multi-purpose reactor until 2021 or longer. There is convincing evidence that the restoration of the MAPLE reactors is technically feasible, but it is highly improbable that a 10 MW MAPLE production reactor can ever be cost-effective. However, conversion of the present 10 MW reactors to 3 MW, without major changes to the structural hardware, warrants serious consideration. Finally, even the 20 kW SLOWPOKE reactor could produce useful quantities of Mo-99. If the present fuel rods were replaced with a small tank containing a solution of low-enriched uranyl sulphate in water, three of these liquid core reactors could supply all of Canada. (author)

  2. Synthesis of Pisolithus Ectomycorrhizae on Pecan Seedlings in Fumigated Soil

    Science.gov (United States)

    Donald H. Marx

    1979-01-01

    Curtis variety of pecan (Carya illinoensis) seedlings were grown for 8 months in fumigated soil infested at sowing with mycelial inoculum of Pisolithus tinctorius. Pisolithus ectomycorrhizae were formed on all inoculated seedlings and significantly improved their growth over control seedlings. Inoculated and control seedlings also formed ectomycorrhizae with naturally...

  3. Fungi of the genus Fusarium as pathogens of soybean seedlings

    Directory of Open Access Journals (Sweden)

    Joanna Marcinkowska

    2013-12-01

    Full Text Available Twenty isolates of fungi of the genus Fusarium collected in the period 1980-1982 from various organs of diseased soybean plants were investigated. Eight of them proved pathogenic to soybean seedlings. The species F. culmorum was most numerously represented among the isolated (4 of 8 pathogens. Isolates of F. sambucinum were also pathogenic (2 of 4 and those of F. soloni (1 of 3, too. The only isolate of F. avenaceum also caused seedling blight. Two isolates of F. oxysporum and two of F. arthrosporioides were not pathogenic. Numerous isolates affected seed gernination and one greatly inhibited growth of the infected seedlings. Pathogenicity was tested in the laboratory in Petri plates on isolate cultures and on filter paper imbibed with fungal inoculum and, in the greenhouse on a peat and perlite substrate. The degree of infection and the character of the disease symptoms depended on the experimental conditions. The results of experiments in plates and in the greenhouse supplemented one another.

  4. Effect of long-term drought on carbon allocation and nitrogen uptake of Pinus sylvestris seedlings

    Science.gov (United States)

    Pumpanen, Jukka; Aaltonen, Heidi; Lindén, Aki; Köster, Kajar; Biasi, Christina; Heinonsalo, Jussi

    2015-04-01

    Weather extremes such as drought events are expected to increase in the future as a result of climate change. The drought affects the allocation of carbon assimilated by plants e.g. by modifying the root to shoot ratio, amount of fine roots and the amount of mycorrhizal fungal hyphae. We studied the effect of long term drought on the allocation of carbon in a common garden experiment with 4-year-old Pinus sylvestris seedlings. Half of the seedlings were exposed to long-term drought by setting the soil water content close to wilting point for over two growing seasons whereas the other half was grown in soil close to field capacity. We conducted a pulse labelling with 13CO2 in the end of the study by injecting a known amount of 13C enriched CO2 to the seedlings and measuring the CO2 uptake and distribution of 13C to the biomass of the seedlings and to the root and rhizosphere respiration. In addition, we studied the effect of drought on the decomposition of needle litter and uptake of nitrogen by 15N labelled needles buried in the soil in litter bags. The litterbags were collected and harvested in the end of the experiment and the changes in microbial community in the litterbags were studied from the phospholipid fatty acid (PLFA) composition. We also determined the 15N isotope concentrations from the needles of the seedlings to study the effect of drought on the nitrogen uptake of the seedlings. Our results indicate that the drought had a significant effect both on the biomass allocation of the seedlings and on the microbial species composition. The amount of carbon allocated belowground was much higher in the seedlings exposed to drought compared to the control seedlings. The seedlings seemed to adapt their carbon allocation to long-term drought to sustain adequate needle biomass and water uptake. The seedlings also adapted their osmotic potential and photosynthesis capacity to sustain the long-term drought as was indicated by the measurements of osmotic potential

  5. Experimental Testing and Computational Fluid Dynamics Simulation of Maple Seeds and Performance Analysis as a Wind Turbine

    Science.gov (United States)

    Holden, Jacob R.

    Descending maple seeds generate lift to slow their fall and remain aloft in a blowing wind; have the wings of these seeds evolved to descend as slowly as possible? A unique energy balance equation, experimental data, and computational fluid dynamics simulations have all been developed to explore this question from a turbomachinery perspective. The computational fluid dynamics in this work is the first to be performed in the relative reference frame. Maple seed performance has been analyzed for the first time based on principles of wind turbine analysis. Application of the Betz Limit and one-dimensional momentum theory allowed for empirical and computational power and thrust coefficients to be computed for maple seeds. It has been determined that the investigated species of maple seeds perform near the Betz limit for power conversion and thrust coefficient. The power coefficient for a maple seed is found to be in the range of 48-54% and the thrust coefficient in the range of 66-84%. From Betz theory, the stream tube area expansion of the maple seed is necessary for power extraction. Further investigation of computational solutions and mechanical analysis find three key reasons for high maple seed performance. First, the area expansion is driven by maple seed lift generation changing the fluid momentum and requiring area to increase. Second, radial flow along the seed surface is promoted by a sustained leading edge vortex that centrifuges low momentum fluid outward. Finally, the area expansion is also driven by the spanwise area variation of the maple seed imparting a radial force on the flow. These mechanisms result in a highly effective device for the purpose of seed dispersal. However, the maple seed also provides insight into fundamental questions about how turbines can most effectively change the momentum of moving fluids in order to extract useful power or dissipate kinetic energy.

  6. Increased Air Temperature during Simulated Autumn Conditions Does Not Increase Photosynthetic Carbon Gain But Affects the Dissipation of Excess Energy in Seedlings of the Evergreen Conifer Jack Pine1[OA

    Science.gov (United States)

    Busch, Florian; Hüner, Norman P.A.; Ensminger, Ingo

    2007-01-01

    Temperature and daylength act as environmental signals that determine the length of the growing season in boreal evergreen conifers. Climate change might affect the seasonal development of these trees, as they will experience naturally decreasing daylength during autumn, while at the same time warmer air temperature will maintain photosynthesis and respiration. We characterized the down-regulation of photosynthetic gas exchange and the mechanisms involved in the dissipation of energy in Jack pine (Pinus banksiana) in controlled environments during a simulated summer-autumn transition under natural conditions and conditions with altered air temperature and photoperiod. Using a factorial design, we dissected the effects of daylength and temperature. Control plants were grown at either warm summer conditions with 16-h photoperiod and 22°C or conditions representing a cool autumn with 8 h/7°C. To assess the impact of photoperiod and temperature on photosynthesis and energy dissipation, plants were also grown under either cold summer (16-h photoperiod/7°C) or warm autumn conditions (8-h photoperiod/22°C). Photosynthetic gas exchange was affected by both daylength and temperature. Assimilation and respiration rates under warm autumn conditions were only about one-half of the summer values but were similar to values obtained for cold summer and natural autumn treatments. In contrast, photosynthetic efficiency was largely determined by temperature but not by daylength. Plants of different treatments followed different strategies for dissipating excess energy. Whereas in the warm summer treatment safe dissipation of excess energy was facilitated via zeaxanthin, in all other treatments dissipation of excess energy was facilitated predominantly via increased aggregation of the light-harvesting complex of photosystem II. These differences were accompanied by a lower deepoxidation state and larger amounts of β-carotene in the warm autumn treatment as well as by changes in

  7. The LEU target development and conversion program for the MAPLE reactors and new processing facility

    International Nuclear Information System (INIS)

    Malkoske, G.R.

    2003-01-01

    The availability of isotope grade, Highly Enriched Uranium (HEU), from the United States for use in the manufacture of targets for molybdenum-99 production in AECL's NRU research reactor has been a key factor to enable MDS Nordion to develop a reliable, secure supply of medical isotopes for the international nuclear medicine community. The molybdenum extraction process from HEU targets is a proven and established method that has reliably produced medical isotopes for several decades. The HEU process provides predictable, consistent yields for our high-volume, molybdenum-99 production. Other medical isotopes such as I-131 and Xe-133, which play an important role in nuclear medicine applications, are also produced from irradiated HEU targets as a by-product of the molybdenum-99 process. To ensure a continued reliable and timely supply of medical isotopes, MDS Nordion is completing the commissioning of two MAPLE reactors and an associated isotope processing facility (the New Processing Facility). The new MAPLE facilities, which will be dedicated exclusively to medical isotope production, will provide an essential contribution to a secure, robust global healthcare system. Design and construction of these facilities has been based on a life cycle management philosophy for the isotope production process. This includes target irradiation, isotope extraction and waste management. The MAPLE reactors will operate with Low Enriched Uranium (LEU) fuel, a significant contribution to the objectives of the RERTR program. The design of the isotope production process in the MAPLE facilities is based on an established process - extraction of isotopes from HEU target material. This is a proven technology that has been demonstrated over more than three decades of operation. However, in support of the RERTR program and in compliance with U.S. legislation, MDS Nordion has undertaken a LEU Target Development and Conversion Program for the MAPLE facilities. This paper will provide an

  8. Presumptive red maple (Acer rubrum) toxicosis in Grevy's zebra (Equus grevyi).

    Science.gov (United States)

    Weber, M; Miller, R E

    1997-03-01

    Two female Grevy's zebras (Equus grevyi), one juvenile and one adult, were treated for hemolytic anemia. The juvenile survived, but the adult animal, which also had methemoglobinemia, was euthanized after it failed to recover from anesthesia. Significant pathologic findings in the adult zebra included generalized icterus, hemoglobinuric nephrosis, and paracentral hepatic necrosis. Serum titers for known infectious causes of anemia were negative. Examination of the zebra holding areas revealed two hybrid red maple (Acer sp.) trees. There was no known exposure to other hemolytic agents. This is the first report of probable red maple-induced hemolysis in zebra.

  9. Surface morphology of thin lysozyme films produced by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Pryds, Nini

    2007-01-01

    Thin films of the protein, lysozyme, have been deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Frozen targets of 0.3-1.0 wt.% lysozyme dissolved in ultrapure water were irradiated by laser light at 355 mn with a fluence of 2 J/cm(2). The surface quality of the thin....... The concentration of lysozyme in the ice matrix apparently does not play any significant role for the morphology of the film. The morphology obtained with MAPLE has been compared with results for direct laser irradiation of a pressed lysozyme sample (i.e. pulsed laser deposition (PLD)). (C) 2007 Elsevier B.V. All...

  10. The effect of sodium hypochlorite solutions on in vitro seedling growth and shoot regeneration of flax (Linum usitatissimum)

    Science.gov (United States)

    Yildiz, Mustafa; Er, Celâl

    2002-04-01

    The aim of this study was to determine the effect of concentration (40, 60, and 80%) and temperature (0, 10, 20, and 30°C) of sodium hypochlorite (NaOCl) solutions on seed germination, in vitro viability and growth of flax seedlings and regeneration capacity of hypocotyl explants. Results showed that seed germination, seedling growth and shoot regeneration were negatively affected by increasing concentration and temperature of disinfectant. The best results in seedling growth and shoot regeneration were obtained when 40% disinfectant concentration at 10°C was used.

  11. Short dry spells in the wet season increase mortality of tropical pioneer seedlings.

    Science.gov (United States)

    Engelbrecht, Bettina M J; Dalling, James W; Pearson, Timothy R H; Wolf, Robert L; Gálvez, David A; Koehler, Tobias; Tyree, Melvin T; Kursar, Thomas A

    2006-06-01

    Variation in plant species performance in response to water availability offers a potential axis for temporal and spatial habitat partitioning and may therefore affect community composition in tropical forests. We hypothesized that short dry spells during the wet season are a significant source of mortality for the newly emerging seedlings of pioneer species that recruit in treefall gaps in tropical forests. An analysis of a 49-year rainfall record for three forests across a rainfall gradient in central Panama confirmed that dry spells of > or = 10 days during the wet season occur on average once a year in a deciduous forest, and once every other year in a semi-deciduous moist and an evergreen wet forest. The effect of wet season dry spells on the recruitment of pioneers was investigated by comparing seedling survival in rain-protected dry plots and irrigated control plots in four large artificially created treefall gaps in a semi-deciduous tropical forest. In rain-protected plots surface soil layers dried rapidly, leading to a strong gradient in water potential within the upper 10 cm of soil. Seedling survival for six pioneer species was significantly lower in rain-protected than in irrigated control plots after only 4 days. The strength of the irrigation effect differed among species, and first became apparent 3-10 days after treatments started. Root allocation patterns were significantly, or marginally significantly, different between species and between two groups of larger and smaller seeded species. However, they were not correlated with seedling drought sensitivity, suggesting allocation is not a key trait for drought sensitivity in pioneer seedlings. Our data provide strong evidence that short dry spells in the wet season differentially affect seedling survivorship of pioneer species, and may therefore have important implications to seedling demography and community dynamics.

  12. Influence of 24-epibrassinolide on seedling growth and distribution of mineral elements in two maize hybrids

    Directory of Open Access Journals (Sweden)

    Waisi Hadi K.

    2017-01-01

    Full Text Available In this study, influence of wide range of 24-epibrassinolide (24-EBL on early growth potential of two maize hybrids (ZP 434 and ZP 704 was examined. Paper concerns germination, seedling biomass, important chlorophylls content, and redistribution of elements (heavy metals and microelements, in a seedlings of the maize hybrids, as influenced by different 24-EBL concentrations. It was found that hybrids react differently to exogenously applied hormone. The biggest differences between two examined maize hybrids considering the germination level were reached with the lowest values at 86% for ZP 704 and 72% for ZP 434, gained at the highest applied concentration of 24-EBL. Seedlings of hybrid ZP 434 reacted positively moderately in the case of shoot length and biomass under the influence of 24-EBL, but seedlings of hybrid ZP 704 had lower values of these parameters under the influence of the phytohormone. Chlorophyll a/b ratios showed that photosynthetic apparatus of seedlings of the hybrids is not active in this stage of development. It was established that 24-EBL affects seedling growth and re-allocation of naturally present mineral elements in early growth stages and that could be one of the reason for poorer growth of ZP 704 treated with various concentrations of 24-EBL, comparing to control. When applied in lower concentrations, 24-EBL is blocking toxic elements such as chromium and nickel to relocate to vital parts of plant, what was case in hybrid ZP704. In case of ZP 434, lower concentrations of 24-EBL are affecting re-allocation of Cu and Cr and these findings suggest that maize hybrid seedlings treated with lower concentrations of 24-EBL could survive and be successful in polluted areas. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31080

  13. Protein and leucine metabolism in maple syrup urine disease

    International Nuclear Information System (INIS)

    Thompson, G.N.; Bresson, J.L.; Pacy, P.J.; Bonnefont, J.P.; Walter, J.H.; Leonard, J.V.; Saudubray, J.M.; Halliday, D.

    1990-01-01

    Constant infusions of [13C]leucine and [2H5]phenylalanine were used to trace leucine and protein kinetics, respectively, in seven children with maple syrup urine disease (MSUD) and eleven controls matched for age and dietary protein intake. Despite significant elevations of plasma leucine (mean 351 mumol/l, range 224-477) in MSUD subjects, mean whole body protein synthesis [3.78 +/- 0.42 (SD) g.kg-1. 24 h-1] and catabolism (4.07 +/- 0.46) were similar to control values (3.69 +/- 0.50 and 4.09 +/- 0.50, respectively). The relationship between phenylalanine and leucine fluxes was also similar in MSUD subjects (mean phenylalanine-leucine flux ratio 0.35 +/- 0.07) and previously reported adult controls (0.33 +/- 0.02). Leucine oxidation was undetectable in four of the MSUD subjects and very low in the other three (less than 4 mumol.kg-1.h-1; controls 13-20). These results show that persistent elevation in leucine concentration has no effect on protein synthesis. The marked disturbance in leucine metabolism in MSUD did not alter the relationship between rates of catabolism of protein to phenylalanine and leucine, which provides further support for the validity of the use of a single amino acid to trace whole body protein metabolism. The minimal leucine oxidation in MSUD differs from findings in other inborn metabolic errors and indicates that in patients with classical MSUD there is no significant route of leucine disposal other than through protein synthesis

  14. Rice Seedling Substrate Produced by Coal Gangue

    Directory of Open Access Journals (Sweden)

    SHAO Yu-fei

    2017-10-01

    Full Text Available Peats are the mostly used material in making rice seedling substrate. However, mining peats could cause environmental problems. In order to reduce or replace peats in rice seedling substrate industry, this paper studied suitable way to configure rice seedling. The coal gangue was used to experiment cultivating rice. Four rice seeding experiments were carried out based on physical and chemical properties of materials attributes. The results showed:(1 Coal gangue was feasible for rice seedling; (2 The maximum adding amount of coal gangue was 80%(volume ratio though the coal gangue need to be activated; (3 In the case of no activated treatment only 38%(volume ratio of coal gangue could be added to the substrate.

  15. Changes in germination characteristics and seedling growth ...

    African Journals Online (AJOL)

    Changes in germination characteristics and seedling growth between storage ... for up to 1 year and the second group was used for un-stored germination test. ... seed germination performance without loss of longevity of tall fescue species, ...

  16. Metal resistance in populations of red maple (Acer rubrum L.) and white birch (Betula papyrifera Marsh.) from a metal-contaminated region and neighbouring non-contaminated regions

    International Nuclear Information System (INIS)

    Kirkey, Fallon M.; Matthews, Jennifer; Ryser, Peter

    2012-01-01

    Metal resistance in populations of Acer rubrum and Betula papyrifera in the industrially contaminated region of Sudbury, Ontario, was compared with resistance in populations from neighbouring uncontaminated regions. In two one-season experiments, seedlings were grown outdoors on contaminated (mainly Cu, Ni) and uncontaminated substrates. Sudbury populations of both species responded less to contamination than populations from uncontaminated regions. In A. rubrum this difference was small. For both species, Sudbury plants were smaller when grown on uncontaminated substrate. B. papyrifera from Sudbury grew better on contaminated substrate than the other populations. There is indication of variation in metal resistance within the populations from the non-contaminated regions. The data shows that trees may develop adaptive resistance to heavy metals, but the low degree of resistance indicates that the development of such resistances are slower than observed for herbaceous species with shorter generation times. - Highlights: ► Metal resistance in trees from an industrially contaminated region was investigated. ► Both red maple and white birch have developed some degree of resistance. ► There is indication of a cost for resistance. ► Populations from non-contaminated regions show variation in response to contamination. - Adaptive metal resistance can also develop in trees with long generation times, but the degree of resistance is lower than for herbaceous species from the same region.

  17. Physiological responses of seeds and seedlings of lettuce submitted to Philodendron bipinnatifidum extract

    Directory of Open Access Journals (Sweden)

    Tiago Zanatta Aumonde

    2013-12-01

    Full Text Available The work was conducted to evaluate the effect of different Philodendron bipinnatifidum Schott. extract concentrations on the physiology and enzymatic metabolism of lettuce seeds and seedlings. The treatments extracts of mature leaves at concentrations of 0, 6, 12, 25 and 50%. Were evaluated the germination, first count germination, speed and germination speed index, length of shoot and primary root, seedling total dry mass, electrical conductivity, chlorophyll content, activity of the enzymes ?-amilase, superoxide dismutase, catalase and ascorbarto peroxidase, lipid peroxidation, hydrogen peroxide content and seedling emergence, length of shoot and total dry mass of emerged seedlings. There was a reduction of germination, germination speed index and total dry mass by increasing the concentration of the extract. While the content of hydrogen peroxide, lipid peroxidation and activity of superoxide dismutase, catalase and peroxidase ascorbarto increased with concentration. The increasing of concentration the leaf extracts of the P. bipinnatifidum negatively affects the activity of the enzyme ?-amylase and causes increase in the activity of antioxidant enzymes, affecting the physiologic performance and growth of lettuce seedlings.

  18. Effects of rhizobacteria on the respiration and growth of Cerasus sachalinensis Kom. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Qin, S.; Zhou, W.; Li, Z.; Lyu, D.

    2016-11-01

    In this study, we investigated the influence of rhizosphere microorganisms on seed germination and root metabolism in Cerasus sachalinensis Kom. We inoculated C. sachalinensis plants with suspensions of dominant bacterial strains isolated from their rhizosphere. Four bacterial strains each with significant growth-promoting or growth-inhibiting effects were screened from the efficient root-colonizing microorganisms. The number of actinomycetes increased and that of fungi decreased significantly in the seedling rhizospheres after rhizobacteria treatment. The growth-promoting bacteria slightly affected the respiration rates and respiratory pathway enzymes, but significantly improved root viability, root carbohydrate concentration and seedling growth. Bacillus cereus, Staphylococcus sp. and Pseudomonas fluorescens were identified as the growth-promoting rhizobacteria; one strain could not be identified. After inoculation with the growth-inhibiting bacteria, the number of fungal colonies in the seedling rhizospheres increased and root viability and respiration rate as well as starch and sucrose accumulation in the roots significantly decreased. The glycolysis, pentose phosphate and alternative oxidase pathways became the major pathways of respiratory metabolism after inoculation with the growth-inhibiting bacteria. The height, leaf number, growth and dry weight of the seedlings decreased significantly in plants inoculated with the growth-inhibiting bacteria. Inoculation of C. sachalinensis rhizosphere with growth-promoting and growth-inhibiting bacteria affected the soil environmental factors such as microbial group composition, nutrient concentration and seedling biomass. (Author)

  19. Line-scan inspection of conifer seedlings

    Science.gov (United States)

    Rigney, Michael P.; Kranzler, Glenn A.

    1993-05-01

    Almost two billion conifer seedlings are produced in the U.S. each year to support reforestation efforts. Seedlings are graded manually to improve viability after transplanting. Manual grading is labor-intensive and subject to human variability. Our previous research demonstrated the feasibility of automated tree seedling inspection with machine vision. Here we describe a system based on line-scan imaging, providing a three-fold increase in resolution and inspection rate. A key aspect of the system is automatic recognition of the seedling root collar. Root collar diameter, shoot height, and projected shoot and root areas are measured. Sturdiness ratio and shoot/root ratio are computed. Grade is determined by comparing measured features with pre-defined set points. Seedlings are automatically sorted. The precision of machine vision and manual measurements was determined in tests at a commercial forest nursery. Manual measurements of stem diameter, shoot height, and sturdiness ratio had standard deviations three times those of machine vision measurements. Projected shoot area was highly correlated (r2 equals 0.90) with shoot volume. Projected root area had good correlation (r2 equals 0.80) with root volume. Seedlings were inspected at rates as high as ten per second.

  20. Clinical and biochemical profiles of maple syrup urine disease in malaysian children.

    Science.gov (United States)

    Yunus, Z Md; Kamaludin, Dp Abg; Mamat, M; Choy, Y S; Ngu, Lh

    2012-01-01

    Maple Syrup Urine Disease (MSUD) is an autosomal recessive disorder caused by defects in the branched-chain α-ketoacid dehydrogenase complex resulting in accumulation of branched-chain amino acids (BCAAs) and corresponding branched-chain ketoacids (BCKAs) in tissues and plasma, which are neurotoxic. Early diagnosis and subsequent nutritional modification management can reduce the morbidity and mortality. Prior to 1990s, the diagnosis of MSUD and other inborn errors of metabolism (IEM) in Malaysia were merely based on clinical suspicion and qualitative one-dimensional thin layer chromatography technique. We have successfully established specific laboratory diagnostic techniques to diagnose MSUD and other IEM. We described here our experience in performing high-risk screening for IEM in Malaysia from 1999 to 2006. We analysed the clinical and biochemical profiles of 25 patients with MSUD. A total of 12,728 plasma and urine samples from patients suspected of having IEM were received from physicians all over Malaysia. Plasma amino acids quantitation using fully automated amino acid analyzer and identification of urinary organic acids using Gas Chromatography Mass Spectrometry (GCMS). Patients' clinical information were obtained from the request forms and case records Results: Twenty-five patients were diagnosed MSUD. Nineteen patients (76%) were affected by classical MSUD, whereas six patients had non-classical MSUD. Delayed diagnosis was common among our case series, and 80% of patients had survived with treatment with mild-to-moderate learning difficulties. Our findings suggested that MSUD is not uncommon in Malaysia especially among the Malay and early laboratory diagnosis is crucial.

  1. Effect of Acinetobacter sp on metalaxyl degradation and metabolite profile of potato seedlings (Solanum tuberosum L. alpha variety.

    Directory of Open Access Journals (Sweden)

    Fabiola G Zuno-Floriano

    Full Text Available One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC-TOF-MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism.

  2. Effects of local biotic neighbors and habitat heterogeneity on tree and shrub seedling survival in an old-growth temperate forest.

    Science.gov (United States)

    Bai, Xuejiao; Queenborough, Simon A; Wang, Xugao; Zhang, Jian; Li, Buhang; Yuan, Zuoqiang; Xing, Dingliang; Lin, Fei; Ye, Ji; Hao, Zhanqing

    2012-11-01

    Seedling dynamics play a crucial role in determining species distributions and coexistence. Exploring causes of variation in seedling dynamics can therefore provide key insights into the factors affecting these phenomena. We examined the relative importance of biotic neighborhood processes and habitat heterogeneity using survival data for 5,827 seedlings in 39 tree and shrub species over 2 years from an old-growth temperate forest in northeastern China. We found significant negative density-dependence effects on survival of tree seedlings, and limited effects of habitat heterogeneity (edaphic and topographic variables) on survival of shrub seedlings. The importance of negative density dependence on young tree seedling survival was replaced by habitat in tree seedlings ≥ 4 years old. As expected, negative density dependence was more apparent in gravity-dispersed species compared to wind-dispersed and animal-dispersed species. Moreover, we found that a community compensatory trend existed for trees. Therefore, although negative density dependence was not as pervasive as in other forest communities, it is an important mechanism for the maintenance of community diversity in this temperate forest. We conclude that both negative density dependence and habitat heterogeneity drive seedling survival, but their relative importance varies with seedling age classes and species traits.

  3. Red fox ( Vulpes vulpes L.) favour seed dispersal, germination and seedling survival of Mediterranean Hackberry ( Celtis australis L.)

    Science.gov (United States)

    Juan, Traba; Sagrario, Arrieta; Jesús, Herranz; Cristina, Clamagirand M.

    2006-07-01

    Seeds of the Mediterranean Hackberry Celtis australis are often encountered in fox faeces. In order to evaluate the effect of gut transit on the size of seeds selected, the rates and speed of germination and on the survival of the seedlings, Mediterranean Hackberry seeds from fox faeces were germinated in a greenhouse. The results were compared with those of seeds taken from ripe, uneaten fruits. Fox-dispersed seeds were smaller and lighter than the control ones and had higher (74% vs. 57%) and more rapid germination (74.5 days vs. 99.2 days). Seedlings from fox-dispersed seeds showed significantly greater survival by the end of the study period (74.1% vs. 43.6%) than the control ones. Survival in seedlings from fox-dispersed seeds was related to germination date, late seedlings showing poorer survival. This relationship was not observed away in the control seedlings. Seed mass did not affect seedling survival. Seedling arising from fox-dispersed seeds grew faster than control ones. These results suggest that fox can play a relevant role as seed disperser of Mediterranean Hackberry.

  4. Economic values for growth and grade changes of sugar maple in the Lake States.

    Science.gov (United States)

    Richard M. Godman; Joseph J. Mendel

    1978-01-01

    Current and expected rates of value increase over a 10-year period were developed for sawtimber-size sugar maple based on variable growth rates, expected merchantable height changes, and butt log grade improvement. These economic guides, along with silvicultural considerations, provide a value basis for selecting trees during thinning and determining final harvest...

  5. Algorithms for the extension of precise and imprecise conditional probability assessments: an implementation with maple V

    Directory of Open Access Journals (Sweden)

    Veronica Biazzo

    2000-05-01

    Full Text Available In this paper, we illustrate an implementation with Maple V of some procedures which allow to exactly propagate precise and imprecise probability assessments. The extension of imprecise assessments is based on a suitable generalization of the concept of coherence of de Finetti. The procedures described are supported by some examples and relevant cases.

  6. Photographic guide of selected external defect indicators and associated internal defects in sugar maple

    Science.gov (United States)

    Everette D. Rast; John A. Beaton; David L. Sonderman

    1991-01-01

    To properly classify or grade logs or trees, one must be able to correctly identify defect indicators and assess the effect of the underlying defect on possible end products. This guide assists the individual in identifying the surface defect indicator and shows the progressive stages of the defect throughout its development for sugar maple. Eleven types of external...

  7. Chemical Compositional, Biological, and Safety Studies of a Novel Maple Syrup Derived Extract for Nutraceutical Applications

    Science.gov (United States)

    2015-01-01

    Maple syrup has nutraceutical potential given the macronutrients (carbohydrates, primarily sucrose), micronutrients (minerals and vitamins), and phytochemicals (primarily phenolics) found in this natural sweetener. We conducted compositional (ash, fiber, carbohydrates, minerals, amino acids, organic acids, vitamins, phytochemicals), in vitro biological, and in vivo safety (animal toxicity) studies on maple syrup extracts (MSX-1 and MSX-2) derived from two declassified maple syrup samples. Along with macronutrient and micronutrient quantification, thirty-three phytochemicals were identified (by HPLC-DAD), and nine phytochemicals, including two new compounds, were isolated and identified (by NMR) from MSX. At doses of up to 1000 mg/kg/day, MSX was well tolerated with no signs of overt toxicity in rats. MSX showed antioxidant (2,2-diphenyl-1-picrylhydrazyl (DPPH) assay) and anti-inflammatory (in RAW 264.7 macrophages) effects and inhibited glucose consumption (by HepG2 cells) in vitro. Thus, MSX should be further investigated for potential nutraceutical applications given its similarity in chemical composition to pure maple syrup. PMID:24983789

  8. A conversion development program to LEU targets for medical isotope production in the MAPLE Facilities

    International Nuclear Information System (INIS)

    Malkoske, G.R.

    2000-01-01

    Historically, the production of molybdenum-99 in the NRU research reactors at Chalk River, Canada has been extracted from reactor targets employing highly enriched uranium (HEU). The molybdenum extraction process from the HEU targets provided predictable, consistent yields for our high-volume molybdenum production process. A reliable supply of HEU for the NRU research reactor targets has enabled MDS Nordion to develop a secure chain of medical isotope supply for the international nuclear medicine community. Each link of the isotope supply chain, from isotope production to patient application, has been established on a proven method of HEU target irradiation and processing. To ensure a continued reliable and timely supply of medical isotopes, the design of the MAPLE facilities was based on our established process - extraction of isotopes from HEU target material. However, in concert with the global trend to utilize low enriched uranium (LEU) in research reactors, MDS Nordion has launched a program to convert the MAPLE facilities to LEU targets. An initial feasibility study was initiated to identify the technical issues to convert the MAPLE targets from HEU to LEU. This paper will present the results of the feasibility study. It will also describe future challenges and opportunities in converting the MAPLE facilities to LEU targets for large scale, commercial medical isotope production. (author)

  9. The Sprouting Potential of Dormant Buds on the Bole of Pole-Size Sugar Maple

    Science.gov (United States)

    Richard M. Godman; Gilbert A. Mattson

    1970-01-01

    A study of epicormic sprouting in pole-size sugar maples showed that all visible dormant buds on the bole were capable of producing epicormic shoots. The buds were induced to break dormancy by applying four methods of crown removal known to stimulate sprouting. The amount of crown removed determined the year that the buds broke dormancy; this may be accounted for by...

  10. The Effects of Maple Integrated Strategy on Engineering Technology Students' Understanding of Integral Calculus

    Science.gov (United States)

    Salleh, Tuan Salwani; Zakaria, Effandi

    2016-01-01

    The objective of this research is to investigate the effectiveness of a learning strategy using Maple in integral calculus. This research was conducted using a quasi-experimental nonequivalent control group design. One hundred engineering technology students at a technical university were chosen at random. The effectiveness of the learning…

  11. Maple (Computer Algebra System) in Teaching Pre-Calculus: Example of Absolute Value Function

    Science.gov (United States)

    Tuluk, Güler

    2014-01-01

    Modules in Computer Algebra Systems (CAS) make Mathematics interesting and easy to understand. The present study focused on the implementation of the algebraic, tabular (numerical), and graphical approaches used for the construction of the concept of absolute value function in teaching mathematical content knowledge along with Maple 9. The study…

  12. Preliminary results of sugar maple carbohydrate and growth response under vacuum and gravity sap extraction

    Science.gov (United States)

    Mark L. Isselhardt; Timothy D. Perkins; Abby K. van den Berg; Paul G. Schaberg

    2016-01-01

    Recent technological advancements have increased the amount of sugar-enriched sap that can be extracted from sugar maple (Acer saccharum). This pilot study quantified overall sugar removal and the impacts of vacuum (60 cm Hg) and gravity sap extraction on residual nonstructural carbohydrate (NSC) concentrations and on stem and twig growth. Vacuum...

  13. Soil water and xylem chemistry in declining sugar maple stands in Pennsylvania

    Science.gov (United States)

    David R. DeWalle; Bryan R. Swistock; William E. Sharpe

    1999-01-01

    Evidence is accumulating that decline of sugar maple, Acer saccharum Marsh., in northern Pennsylvania may be related to overall site fertility as reflected in the chemistry of soil water and bolewood xylem. In this paper we discuss factors related to varying site fertility, including effects of soil liming, past glacialion, topographic position and...

  14. Seasonal patterns of reserve and soluble carbohydrates in mature sugar maple (Acer saccharum)

    Science.gov (United States)

    B.L. Wong; K.L. Baggett; A.H. Rye

    2003-01-01

    Sugar maple (Acer saccharum Marsh.) trees exhibit seasonal patterns of production, accumulation, and utilization of nonstructural carbohydrates that are closely correlated with phenological events and (or) physiological processes. The simultaneous seasonal patterns of both reserve and soluble carbohydrates in the leaves, twigs, branches, and trunks of healthy mature...

  15. First Record of Eutypella parasitica on Maples in Urban Area in Croatia

    Directory of Open Access Journals (Sweden)

    Dario Ivić

    2017-01-01

    Full Text Available Background and Purpose: Eutypella parasitica, a plant pathogenic fungus attacking maples (Acer spp. was detected for the first time in Croatia in 2007. From 2007 to 2014, it was found only in forests, on several trees in Hum na Sutli, near Slovenian border. In 2015, the presence of Eutypella parasitica was monitored for the first time in urban areas. Materials and Methods: Within the official survey programme, 23 visual surveys were conducted and 24 samples were collected and analysed for the presence of fungi. E. parasitica was found in Bundek Park in Zagreb. Typical symptoms of Eutypella canker were detected on two field maples (Acer campestre and two boxelder maples (Acer negundo. Twelve isolates were collected from symptomatic trees. Conclusions: Eleven out of twelve isolates from four trees were confirmed as E. parasitica by species-specific polymerase chain reaction. This is the first report of E. parasitica in Zagreb, the first record of E. parasitica in Croatia outside forests, as well as a record of a new host species in Croatia, boxelder maple (A. negundo. Introduction pathway of E. parasitica in Zagreb remains unknown.

  16. Symbiotic maple saps minimize disruption of the mice intestinal microbiota after oral antibiotic administration.

    Science.gov (United States)

    Hammami, Riadh; Ben Abdallah, Nour; Barbeau, Julie; Fliss, Ismail

    2015-01-01

    This study was undertaken to evaluate the in vivo impact of new symbiotic products based on liquid maple sap or its concentrate. Sap and concentrate, with or without inulin (2%), were inoculated with Bifidobacterium lactis Bb12 and Lactobacillus rhamnosus GG valio at initial counts of 2-4 × 10(8) cfu mL(-1). The experiments started with intra-gastric administration of antibiotic (kanamycin 40 mg in 0.1 cc) (to induce microbiota disturbance and/or diarrhea) to 3-to-5-week-old C57BL/6 female mice followed by a combination of prebiotic and probiotics included in the maple sap or its concentrate for a week. The combination inulin and probiotics in maple sap and concentrate appeared to minimize the antibiotic-induced breakdown of mice microbiota with a marked effect on bifidobacterium and bacteroides levels, thus permitting a more rapid re-establishment of the baseline microbiota levels. Results suggest that maple sap and its concentrate represent good candidates for the production of non-dairy functional foods.

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

    Science.gov (United States)

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

    2015-01-01

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

  18. High laser-fluence deposition of organic materials in water ice matrices by ''MAPLE''

    DEFF Research Database (Denmark)

    Christensen, Bo Toftmann; Rodrigo, K.; Schou, Jørgen

    2005-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) is a deposition technique for organic material. Water ice was used as a matrix for the biotechnologically important guest material, polyethylene glycol (PEG), for concentrations from 0.5 to 4 wt.%. The target was irradiated with 6 ns laser pulses...

  19. Validation of the ASSERT subchannel code for MAPLE-X10 reactor conditions

    International Nuclear Information System (INIS)

    Carver, M.B.; Kiteley, J.C.; Junop, S.V.; Wasilewicz, J.F.

    1993-01-01

    The ASSERT subchannel analysis code has been developed specifically to model flow and phase distributions within CANDU fuel channels. Recently, ASSERT has been adapted for use in simulating the MAPLE-X10 reactor. ASSERT uses an advanced drift-flux model, which permits the phases to have unequal velocities and unequal temperatures (UVUT), and thus can model non-equilibrium effects such as phase separation tendencies and subcooled boiling. Modelling subcooled boiling accurately is particularly important for MAPLE-X10. This paper briefly summarizes the non-equilibrium model used in the ASSERT code, the equations used to represent these models, and the algorithms used to solve the equations numerically. Very few modifications to the ASSERT models were needed to address MAPLE conditions. These centered on the manner in which finned fuel rods are treated, and they are discussed in the paper. The paper also gives results from validation exercises, in which the ASSERT code predictions of subcooled boiling void-fraction and critical heat flux were compared to experiments using MAPLE-X10 finned fuel elements in annuli and various bundles. 18 refs., 13 figs., 3 tabs

  20. MHD PbLi experiments in MaPLE loop at UCLA

    International Nuclear Information System (INIS)

    Courtessole, C.; Smolentsev, S.; Sketchley, T.; Abdou, M.

    2016-01-01

    Highlights: • The paper overviews the MaPLE facility at UCLA: one-of-a-few PbLi MHD loop in the world. • We present the progress achieved in development and testing of high-temperature PbLi flow diagnostics. • The most important MHD experiments carried out since the first loop operation in 2011 are summarized. - Abstract: Experiments on magnetohydrodynamic (MHD) flows are critical to understanding complex flow phenomena in ducts of liquid metal blankets, in particular those that utilize eutectic alloy lead–lithium as breeder/coolant, such as self-cooled, dual-coolant and helium-cooled lead–lithium blanket concepts. The primary goal of MHD experiments at UCLA using the liquid metal flow facility called MaPLE (Magnetohydrodynamic PbLi Experiment) is to address important MHD effects, heat transfer and flow materials interactions in blanket-relevant conditions. The paper overviews the one-of-a-kind MaPLE loop at UCLA and presents recent experimental activities, including the development and testing of high-temperature PbLi flow diagnostics and experiments that have been performed since the first loop operation in 2011. We also discuss MaPLE upgrades, which need to be done to substantially expand the experimental capabilities towards a new class of MHD flow phenomena that includes buoyancy effects.

  1. The Minnesota Maple Series: Community-Generated Knowledge Delivered through an Extension Website

    Science.gov (United States)

    Wilsey, David S.; Miedtke, Juile A.; Sagor, Eli

    2012-01-01

    Extension continuously seeks novel and effective approaches to outreach and education. The recent retirement of a longtime content specialist catalyzed members of University of Minnesota Extension's Forestry team to reflect on our instructional capacity (internal and external) and educational design in the realm of maple syrup production. We…

  2. Analysis of reactivity feedback effects of void and temperature in the MAPLE-X10 reactor

    International Nuclear Information System (INIS)

    Carlson, P.A.; Heeds, W.; Shim, S.Y.; King, S.G.

    1992-07-01

    The methods used for evaluating the void and temperature reactivity coefficients for the MAPLE-X10 Reactor are described and factors used in estimating their accuracy are discussed. The report presents representative transient analysis results using the CATHENA thermalhydraulics code. The role of the reactivity coefficients and their precision is discussed. The results are reviewed in terms of their safety implications

  3. MHD PbLi experiments in MaPLE loop at UCLA

    Energy Technology Data Exchange (ETDEWEB)

    Courtessole, C., E-mail: cyril@fusion.ucla.edu; Smolentsev, S.; Sketchley, T.; Abdou, M.

    2016-11-01

    Highlights: • The paper overviews the MaPLE facility at UCLA: one-of-a-few PbLi MHD loop in the world. • We present the progress achieved in development and testing of high-temperature PbLi flow diagnostics. • The most important MHD experiments carried out since the first loop operation in 2011 are summarized. - Abstract: Experiments on magnetohydrodynamic (MHD) flows are critical to understanding complex flow phenomena in ducts of liquid metal blankets, in particular those that utilize eutectic alloy lead–lithium as breeder/coolant, such as self-cooled, dual-coolant and helium-cooled lead–lithium blanket concepts. The primary goal of MHD experiments at UCLA using the liquid metal flow facility called MaPLE (Magnetohydrodynamic PbLi Experiment) is to address important MHD effects, heat transfer and flow materials interactions in blanket-relevant conditions. The paper overviews the one-of-a-kind MaPLE loop at UCLA and presents recent experimental activities, including the development and testing of high-temperature PbLi flow diagnostics and experiments that have been performed since the first loop operation in 2011. We also discuss MaPLE upgrades, which need to be done to substantially expand the experimental capabilities towards a new class of MHD flow phenomena that includes buoyancy effects.

  4. MICROBIAL COLONIZATION, RESPIRATION, AND BREAKDOWN OF MAPLE LEAVES ALONG A STREAM-MARSH CONTINUUM

    Science.gov (United States)

    Breakdown rates, macroinvertebrate and bacterial colonization, and microbial respiration were measured on decaying maple (Acer saccharum) leaves at three sites along a stream-marsh continuum. Breakdown rates (-k+-SE) were 0.0284+-0.0045 d-1 for leaves in a high-gradient, non-tida...

  5. Black bark as an indicator of bird peck defect in sugar maple

    Science.gov (United States)

    John H. Ohman; K.J., Jr. Kessler

    1964-01-01

    Portions of the lower bole of occasional sugar maples (Acer saccharum Marsh.) in Lake States northern hardwood stands are sooty black in sharp contrast to the normal gray. The blackened areas may encircle the entire stem or be confined to a narrow band; they have been observed as high as 25 feet but generally extend about 15 feet above the ground....

  6. Development of novel genic microsatellite markers from transcriptome sequencing in sugar maple (Acer saccharum Marsh.).

    Science.gov (United States)

    Harmon, Monica; Lane, Thomas; Staton, Margaret; Coggeshall, Mark V; Best, Teodora; Chen, Chien-Chih; Liang, Haiying; Zembower, Nicole; Drautz-Moses, Daniela I; Hwee, Yap Zhei; Schuster, Stephan C; Schlarbaum, Scott E; Carlson, John E; Gailing, Oliver

    2017-08-08

    Sugar maple (Acer saccharum Marsh.) is a hardwood tree species native to northeastern North America and economically valued for its wood and sap. Yet, few molecular genetic resources have been developed for this species to date. Microsatellite markers have been a useful tool in population genetics, e.g., to monitor genetic variation and to analyze gene flow patterns. The objective of this study is to develop a reference transcriptome and microsatellite markers in sugar maple. A set of 117,861 putative unique transcripts were assembled using 29.2 Gb of RNA sequencing data derived from different tissues and stress treatments. From this set of sequences a total of 1068 microsatellite motifs were identified. Out of 58 genic microsatellite markers tested on a population of 47 sugar maple trees in upper Michigan, 22 amplified well, of which 16 were polymorphic and 6 were monomorphic. Values for expected heterozygosity varied from 0.224 to 0.726 for individual loci. Of the 16 polymorphic markers, 15 exhibited transferability to other Acer L. species. Genic microsatellite markers can be applied to analyze genetic variation in potentially adaptive genes relative to genomic reference markers as a basis for the management of sugar maple genetic resources in the face of climate change.

  7. Identification of protoxins and a microbial basis for red maple (Acer rubrum) toxicosis in equines.

    Science.gov (United States)

    Agrawal, Karan; Ebel, Joseph G; Altier, Craig; Bischoff, Karyn

    2013-01-01

    The leaves of Acer rubrum (red maple), especially when wilted in the fall, cause severe oxidative damage to equine erythrocytes, leading to potentially fatal methemoglobinemia and hemolytic anemia. Gallic acid and tannins from A. rubrum leaves have been implicated as the toxic compounds responsible for red maple toxicosis, but the mechanism of action and toxic principle(s) have not been elucidated to date. In order to investigate further how red maple toxicosis occurs, aqueous solutions of gallic acid, tannic acid, and ground dried A. rubrum leaves were incubated with contents of equine ileum, jejunum, cecum, colon, and liver, and then analyzed for the metabolite pyrogallol, as pyrogallol is a more potent oxidizing agent. Gallic acid was observed to be metabolized to pyrogallol maximally in equine ileum contents in the first 24 hr. Incubation of tannic acid and A. rubrum leaves, individually with ileum contents, produced gallic acid and, subsequently, pyrogallol. Ileum suspensions, when passed through a filter to exclude microbes but not enzymes, formed no pyrogallol, suggesting a microbial basis to the pathway. Bacteria isolated from ileum capable of pyrogallol formation were identified as Klebsiella pneumoniae and Enterobacter cloacae. Therefore, gallotannins and free gallic acid are present in A. rubrum leaves and can be metabolized by K. pneumoniae and E. cloacae found in the equine ileum to form pyrogallol either directly or through a gallic acid intermediate (gallotannins). Identification of these compounds and their physiological effects is necessary for the development of effective treatments for red maple toxicosis in equines.

  8. Chemical compositional, biological, and safety studies of a novel maple syrup derived extract for nutraceutical applications.

    Science.gov (United States)

    Zhang, Yan; Yuan, Tao; Li, Liya; Nahar, Pragati; Slitt, Angela; Seeram, Navindra P

    2014-07-16

    Maple syrup has nutraceutical potential given the macronutrients (carbohydrates, primarily sucrose), micronutrients (minerals and vitamins), and phytochemicals (primarily phenolics) found in this natural sweetener. We conducted compositional (ash, fiber, carbohydrates, minerals, amino acids, organic acids, vitamins, phytochemicals), in vitro biological, and in vivo safety (animal toxicity) studies on maple syrup extracts (MSX-1 and MSX-2) derived from two declassified maple syrup samples. Along with macronutrient and micronutrient quantification, thirty-three phytochemicals were identified (by HPLC-DAD), and nine phytochemicals, including two new compounds, were isolated and identified (by NMR) from MSX. At doses of up to 1000 mg/kg/day, MSX was well tolerated with no signs of overt toxicity in rats. MSX showed antioxidant (2,2-diphenyl-1-picrylhydrazyl (DPPH) assay) and anti-inflammatory (in RAW 264.7 macrophages) effects and inhibited glucose consumption (by HepG2 cells) in vitro. Thus, MSX should be further investigated for potential nutraceutical applications given its similarity in chemical composition to pure maple syrup.

  9. Characterization of lysozyme films produced by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Kingshott, Peter

    2007-01-01

    Thin lysozyme films of thickness up to more than 100 nm have been produced in a dry environment by MAPLE (matrix assisted pulsed laser evaporation) from a water ice matrix. Analysis of the films demonstrates that a significant part of the lysozyme molecules is transferred to the substrate without...

  10. RIR MAPLE Procedure for Deposition of Carbon Rich Si/C/H Films

    Czech Academy of Sciences Publication Activity Database

    Dřínek, Vladislav; Strašák, Tomáš; Novotný, F.; Fajgar, Radek; Bastl, Zdeněk

    2014-01-01

    Roč. 292, FEB 15 (2014), s. 413-419 ISSN 0169-4332 R&D Projects: GA ČR GA13-25747S Grant - others:MŠMT(CZ) RVO6840770 Institutional support: RVO:67985858 ; RVO:61388955 Keywords : MAPLE * dendrimer * SiC * DLC * cross-kinking Subject RIV: CA - Inorganic Chemistry Impact factor: 2.711, year: 2014

  11. Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest

    Science.gov (United States)

    Joshua M. Halman; Paul G. Schaberg; Gary J. Hawley; Linda H. Pardo; Timothy J. Fahey

    2013-01-01

    Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature...

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

    Science.gov (United States)

    L. O. Safford

    1973-01-01

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

  13. Red maple (Acer rubrum) response to prescribed burning on the William B. Bankhead National Forest, Alabama

    Science.gov (United States)

    Stacy L. Clark; Callie Jo Schweitzer

    2013-01-01

    Prescribed burning is used as a management tool on national forests in the Southeastern United States to maintain oak (Quercus spp.) -dominated forest or woodland habitat. Few studies have examined response to burning at the stand, plot, and tree level. We documented red maple (Acer rubrum) response to dormant-season prescribed...

  14. Processing Maple Syrup with a Vapor Compression Distiller: An Economic Analysis

    Science.gov (United States)

    Lawrence D. Garrett

    1977-01-01

    A test of vapor compression distillers for processing maple syrup revealed that: (1) vapor compression equipment tested evaporated 1 pound of water with .047 pounds of steam equivalent (electrical energy); open-pan evaporators of similar capacity required 1.5 pounds of steam equivalent (oil energy) to produce 1 pound of water; (2) vapor compression evaporation produced...

  15. Chronic drought stress reduced but not protected Shantung maple (Acer truncatum Bunge) from adverse effects of ozone (O3) on growth and physiology in the suburb of Beijing, China.

    Science.gov (United States)

    Li, Li; Manning, William J; Tong, Lei; Wang, Xiaoke

    2015-06-01

    A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O3) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012-2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (Asat) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O3 - induced reductions in Asat, Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O3. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Shrinking windows of opportunity for oak seedling establishment in southern California mountains

    Science.gov (United States)

    Davis, Frank W.; Sweet, Lynn C.; Serra-Diaz, Josep M.; Franklin, Janet; McCullough, Ian M.; Flint, Alan L.; Flint, Lorraine E.; Dingman, John; Regan, Helen M.; Syphard, Alexandra D.; Hannah, Lee; Redmond, Kelly; Moritz, Max A.

    2016-01-01

    interannual climatic variation when assessing how seedling establishment and colonization processes could be affected by climate change.

  17. Fertility-dependent effects of ectomycorrhizal fungal communities on white spruce seedling nutrition.

    Science.gov (United States)

    Smith, Alistair J H; Potvin, Lynette R; Lilleskov, Erik A

    2015-11-01

    Ectomycorrhizal fungi (EcMF) typically colonize nursery seedlings, but nutritional and growth effects of these communities are only partly understood. To examine these effects, Picea glauca seedlings collected from a tree nursery naturally colonized by three dominant EcMF were divided between fertilized and unfertilized treatments. After one growing season seedlings were harvested, ectomycorrhizas identified using DNA sequencing, and seedlings analyzed for leaf nutrient concentration and content, and biomass parameters. EcMF community structure-nutrient interactions were tested using nonmetric multidimensional scaling (NMDS) combined with vector analysis of foliar nutrients and biomass. We identified three dominant species: Amphinema sp., Atheliaceae sp., and Thelephora terrestris. NMDS + envfit revealed significant community effects on seedling nutrition that differed with fertilization treatment. PERMANOVA and regression analyses uncovered significant species effects on host nutrient concentration, content, and stoichiometry. Amphinema sp. had a significant positive effect on phosphorus (P), calcium and zinc concentration, and P content; in contrast, T. terrestris had a negative effect on P concentration. In the unfertilized treatment, percent abundance of the Amphinema sp. negatively affected foliar nitrogen (N) concentration but not content, and reduced foliar N/P. In fertilized seedlings, Amphinema sp. was positively related to foliar concentrations of N, magnesium, and boron, and both concentration and content of manganese, and Atheliaceae sp. had a negative relationship with P content. Findings shed light on the community and species effects on seedling condition, revealing clear functional differences among dominants. The approach used should be scalable to explore function in more complex communities composed of unculturable EcMF.

  18. The effect of ectomycorrhizal fungi forming symbiosis with Pinus pinaster seedlings exposed to cadmium

    International Nuclear Information System (INIS)

    Sousa, Nadine R.; Ramos, Miguel A.; Marques, Ana P.G.C.; Castro, Paula M.L.

    2012-01-01

    Cadmium is one of the most toxic heavy metals and its accumulation in the upper layers of forest soils affects plants, microorganisms and their interactions. Adequate strategies for the reforestation of metal contaminated sites are of vital importance. The aim of this work was to evaluate the response of Pinus pinaster seedlings to Cd exposure and to assess the effect of inoculation with two selected ectomycorrhizal fungi, Suillus bovinus and Rhizopogon roseolus on that response. Seedlings were exposed to soil contaminated at 15 and 30 mg Cd kg −1 . Shoot biomass of P. pinaster decreased ca. 36% when exposed to 15 mg Cd kg −1 . Overall, colonization by S. bovinus significantly enhanced shoot development up to 30% in contaminated soil while colonization by R. roseolus produced no significant effect at both Cd concentrations tested and significantly increased the level of Cd in the shoots at both Cd concentrations. Metal accumulation in the shoots and roots of non-inoculated and S. bovinus-inoculated seedlings increased at the higher Cd levels whereas R. roseolus-inoculated seedlings were not sensitive to Cd variation in the soil. The results from our research show that inoculation with ECM fungi has a significant impact on metal uptake and development of P. pinaster seedlings; the differential response induced by the two tested species highlights the importance of selecting the appropriate strains for nursery inoculation, and, as such, this biological tool ought to be considered in reforestation processes of heavy metal contaminated areas by woody species. - Highlights: ► Ectomycorrhizal fungi can aid the reforestation of heavy metal contaminated areas. ► Cd inhibited the growth of non-inoculated 6 months-old Pinus pinaster seedlings. ► Inoculation with Suillus bovinus enhanced P. pinaster growth in Cd contaminated soil. ► Mycorrhizal symbiosis influenced the accumulation of Cd in P. pinaster seedlings.

  19. The effect of ectomycorrhizal fungi forming symbiosis with Pinus pinaster seedlings exposed to cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Nadine R.; Ramos, Miguel A.; Marques, Ana P.G.C.; Castro, Paula M.L., E-mail: plcastro@esb.ucp.pt

    2012-01-01

    Cadmium is one of the most toxic heavy metals and its accumulation in the upper layers of forest soils affects plants, microorganisms and their interactions. Adequate strategies for the reforestation of metal contaminated sites are of vital importance. The aim of this work was to evaluate the response of Pinus pinaster seedlings to Cd exposure and to assess the effect of inoculation with two selected ectomycorrhizal fungi, Suillus bovinus and Rhizopogon roseolus on that response. Seedlings were exposed to soil contaminated at 15 and 30 mg Cd kg{sup -1}. Shoot biomass of P. pinaster decreased ca. 36% when exposed to 15 mg Cd kg{sup -1}. Overall, colonization by S. bovinus significantly enhanced shoot development up to 30% in contaminated soil while colonization by R. roseolus produced no significant effect at both Cd concentrations tested and significantly increased the level of Cd in the shoots at both Cd concentrations. Metal accumulation in the shoots and roots of non-inoculated and S. bovinus-inoculated seedlings increased at the higher Cd levels whereas R. roseolus-inoculated seedlings were not sensitive to Cd variation in the soil. The results from our research show that inoculation with ECM fungi has a significant impact on metal uptake and development of P. pinaster seedlings; the differential response induced by the two tested species highlights the importance of selecting the appropriate strains for nursery inoculation, and, as such, this biological tool ought to be considered in reforestation processes of heavy metal contaminated areas by woody species. - Highlights: Black-Right-Pointing-Pointer Ectomycorrhizal fungi can aid the reforestation of heavy metal contaminated areas. Black-Right-Pointing-Pointer Cd inhibited the growth of non-inoculated 6 months-old Pinus pinaster seedlings. Black-Right-Pointing-Pointer Inoculation with Suillus bovinus enhanced P. pinaster growth in Cd contaminated soil. Black-Right-Pointing-Pointer Mycorrhizal symbiosis

  20. Seedling establishment in a masting desert shrub parallels the pattern for forest trees

    Science.gov (United States)

    Meyer, Susan E.; Pendleton, Burton K.

    2015-05-01

    The masting phenomenon along with its accompanying suite of seedling adaptive traits has been well studied in forest trees but has rarely been examined in desert shrubs. Blackbrush (Coleogyne ramosissima) is a regionally dominant North American desert shrub whose seeds are produced in mast events and scatter-hoarded by rodents. We followed the fate of seedlings in intact stands vs. small-scale disturbances at four contrasting sites for nine growing seasons following emergence after a mast year. The primary cause of first-year mortality was post-emergence cache excavation and seedling predation, with contrasting impacts at sites with different heteromyid rodent seed predators. Long-term establishment patterns were strongly affected by rodent activity in the weeks following emergence. Survivorship curves generally showed decreased mortality risk with age but differed among sites even after the first year. There were no detectable effects of inter-annual precipitation variability or site climatic differences on survival. Intraspecific competition from conspecific adults had strong impacts on survival and growth, both of which were higher on small-scale disturbances, but similar in openings and under shrub crowns in intact stands. This suggests that adult plants preempted soil resources in the interspaces. Aside from effects on seedling predation, there was little evidence for facilitation or interference beneath adult plant crowns. Plants in intact stands were still small and clearly juvenile after nine years, showing that blackbrush forms cohorts of suppressed plants similar to the seedling banks of closed forests. Seedling banks function in the absence of a persistent seed bank in replacement after adult plant death (gap formation), which is temporally uncoupled from masting and associated recruitment events. This study demonstrates that the seedling establishment syndrome associated with masting has evolved in desert shrublands as well as in forests.

  1. MODELING IN MAPLE AS THE RESEARCHING MEANS OF FUNDAMENTAL CONCEPTS AND PROCEDURES IN LINEAR ALGEBRA

    Directory of Open Access Journals (Sweden)

    Vasil Kushnir

    2016-05-01

    Full Text Available The article is devoted to binary technology and "fundamental training technology." Binary training refers to the simultaneous teaching of mathematics and computer science, for example differential equations and Maple, linear algebra and Maple. Moreover the system of traditional course of Maple is not performed. The use of the opportunities of Maple-technology in teaching mathematics is based on the following fundamental concepts of computer science as an algorithm, program, a linear program, cycle, branching, relative operators, etc. That’s why only a certain system of command operators in Maple is considered. They are necessary for fundamental concepts of linear algebra and differential equations studying in Maple-environment. Relative name - "the technology of fundamental training" reflects the study of fundamental mathematical concepts and procedures that express the properties of these concepts in Maple-environment. This article deals with the study of complex fundamental concepts of linear algebra (determinant of the matrix and algorithm of its calculation, the characteristic polynomial of the matrix and the eigenvalues of matrix, canonical form of characteristic matrix, eigenvectors of matrix, elementary divisors of the characteristic matrix, etc., which are discussed in the appropriate courses briefly enough, and sometimes are not considered at all, but they are important in linear systems of differential equations, asymptotic methods for solving differential equations, systems of linear equations. Herewith complex and voluminous procedures of finding of these linear algebra concepts embedded in Maple can be performed as a result of a simple command-operator. Especially important issue is building matrix to canonical form. In fact matrix functions are effectively reduced to the functions of the diagonal matrix or matrix in Jordan canonical form. These matrices are used to rise a square matrix to a power, to extract the roots of the n

  2. Management intensity and genetics affect loblolly pine seedling performance

    Science.gov (United States)

    Scott D. Roberts; Randall J. Rousseau; B. Landis Herrin

    2012-01-01

    Capturing potential genetic gains from tree improvement programs requires selection of the appropriate genetic stock and application of appropriate silvicultural management techniques. Limited information is available on how specific loblolly pine varietal genotypes perform under differing growing environments and management approaches. This study was established in...

  3. Natural regeneration of whitebark pine: Factors affecting seedling density

    Science.gov (United States)

    S. Goeking; D. Izlar

    2014-01-01

    Whitebark pine (Pinus albicaulis) is an ecologically important species in high-altitude areas of the western United States and Canada due to the habitat and food source it provides for Clark’s nutcrackers, red squirrels, grizzly bears, and other animals. Whitebark pine stands have recently experienced high mortality due to wildfire, white pine blister rust, and a...

  4. Biomaterial thin film deposition and characterization by means of MAPLE technique

    International Nuclear Information System (INIS)

    Bloisi, F.; Vicari, L.; Papa, R.; Califano, V.; Pedrazzani, R.; Bontempi, E.; Depero, L.E.

    2007-01-01

    Polyethylene glycol (PEG) is a polymer with technologically important applications, especially as a biomaterial. Several biomedical applications (such as tissue engineering, spatial patterning of cells, anti-biofouling and biocompatible coatings) require the application of high quality PEG thin films. In order to have a good adhesion to substrate chemically modified polymer molecules have been used, but for some 'in vivo' applications it is essential to deposit a film with the same chemical and structural properties of bulk PEG. Pulsed laser deposition (PLD) technique is generally able to produce high quality thin films but it is inadequate for polymer/organic molecules. MAPLE (Matrix Assisted Pulsed Laser Evaporation) is a recently developed PLD based thin film deposition technique, particularly well suited for organic/polymer thin film deposition. Up to now MAPLE depositions have been carried out mainly by means of modified PLD systems, using excimer lasers operating in UV, but the use of less energetic radiations can minimize the photochemical decomposition of the polymer molecules. We have used a deposition system explicitly designed for MAPLE technique connected to a Q-switched Ng:YAG pulsed laser which can be operated at different wavelength ranging from IR to UV in order to optimise the deposition parameters. The capability of MAPLE technique to deposit PEG has been confirmed and preliminary results show that visible (532 nm wavelength) radiation gives better results with respect to UV (355 nm) radiation. Despite usually UV wavelengths have been used and even if more systematic tests must be performed, it is important to underline that the choice of laser wavelength plays an important role in the application of MAPLE thin film deposition technique

  5. Association analysis of salt tolerance in cowpea (Vigna unguiculata (L.) Walp) at germination and seedling stages

    Science.gov (United States)

    Cowpea is one of the most important cultivated legumes in Africa. The worldwide annual production in cowpea dry seed is 5.4 million metric tons. However, cowpea is unfavorably affected by salinity stress at germination and seedling stages, which is exacerbated by the effects of climate change. The l...

  6. Stocktype and vegetative competition influences on Pseudotsuga menziesii and Larix occidentalis seedling establishment

    Science.gov (United States)

    Jeremiah R. Pinto; Bridget A. McNassar; Olga A. Kildisheva; Anthony S. Davis

    2018-01-01

    Douglas fir (Pseudotsuga menziesii var. glauca (Mayr) Franco), and western larch (Larix occidentalis Nutt.) are species of ecological and commercial importance that occur throughout the Western United States. Effective reforestation of these species relies on successful seedling establishment, which is affected by planting stock quality, stocktype size, and...

  7. Effects of temperature on Pinus patula seedlings growing in pots in a ...

    African Journals Online (AJOL)

    The re-establishment of Pinus patula seedlings into sites with high harvesting residue (slash) loads can negatively affect the survival of these plants. Field trials have examined the role that insect pests and fungal diseases play in causing this phenomenon. Research has also indicated that temperatures at ground level tend ...

  8. Variation in photosynthesis and stomatal conductance among red maple (Acer rubrum) urban planted cultivars and wildtype trees in the southeastern United States.

    Science.gov (United States)

    Lahr, Eleanor C; Dunn, Robert R; Frank, Steven D

    2018-01-01

    Photosynthesis is a fundamental process that trees perform over fluctuating environmental conditions. This study of red maple (Acer rubrum L.) characterizes photosynthesis, stomatal conductance, and water use efficiency in planted cultivars relative to wildtype trees. Red maple is common in cities, yet there is little understanding of how physiological processes affect the long-term growth, condition, and ecosystem services provided by urban trees. In the first year of our study, we measured leaf-level gas exchange and performed short-term temperature curves on urban planted cultivars and on suburban and rural wildtype trees. In the second year, we compared urban planted cultivars and urban wildtype trees. In the first year, urban planted trees had higher maximum rates of photosynthesis and higher overall rates of photosynthesis and stomatal conductance throughout the summer, relative to suburban or rural wildtype trees. Urban planted trees again had higher maximum rates of photosynthesis in the second year. However, urban wildtype trees had higher water use efficiency as air temperatures increased and similar overall rates of photosynthesis, relative to cultivars, in mid and late summer. Our results show that physiological differences between cultivars and wildtype trees may relate to differences in their genetic background and their responses to local environmental conditions, contingent on the identity of the horticultural variety. Overall, our results suggest that wildtype trees should be considered for some urban locations, and our study is valuable in demonstrating how site type and tree type can inform tree planting strategies and improve long-term urban forest sustainability.

  9. Soil solution and sugar maple response to NH(4)NO (3) additions in a base-poor northern hardwood forest of Québec, Canada.

    Science.gov (United States)

    Moore, Jean-David; Houle, Daniel

    2009-08-01

    Nitrogen additions (NH4NO3) at rates of three- and ten-fold ambient atmospheric deposition (8.5 kg ha(-1) year(-1)) were realised in an acid- and base-poor northern hardwood forest of Québec, Canada. Soil solution chemistry, foliar chemistry, crown dieback and basal area growth of sugar maple (Acer saccharum Marsh.) were measured. Except for a transitory increase of NO3 and NH4 concentrations, there was no persistent increase in their level in soil solution 3 years after N treatments, with the exception of one plot out of three, that received the highest N addition, beginning to show persistent and high NO3 concentrations after 2 years of N additions. Three years of N additions have significantly increased the N DRIS index of sugar maple but not N foliar concentration. Potassium, Ca and Mn foliar concentrations, as well as P and Ca DRIS indices, decreased in treated plots after 3 years. No treatment effect was observed for basal area growth and dieback rate. One unexpected result was the significant decrease in foliar Ca even in the treated plots that received low N rates, despite the absence of significant NO3-induced leaching of Ca. The mechanism responsible for the decrease in foliar Ca is not known. Our results, however, clearly demonstrate that increased N deposition at sites with low base saturation may affect Ca nutrition even when clear signs of N saturation are not observed.

  10. Development and UFLC-MS/MS Characterization of a Product-Specific Standard for Phenolic Quantification of Maple-Derived Foods.

    Science.gov (United States)

    Liu, Yongqiang; Ma, Hang; Seeram, Navindra P

    2016-05-04

    The phenolic contents of plant foods are commonly quantified by the Folin-Ciocalteu assay based on gallic acid equivalents (GAEs). However, this may lead to inaccuracies because gallic acid is not always representative of the structural heterogeneity of plant phenolics. Therefore, product-specific standards have been developed for the phenolic quantification of several foods. Currently, maple-derived foods (syrup, sugar, sap/water, and extracts) are quantified for phenolic contents based on GAEs. Because lignans are the predominant phenolics present in maple, herein, a maple phenolic lignan-enriched standard (MaPLES) was purified (by chromatography) and characterized (by UFLC-MS/MS with lignans previously isolated from maple syrup). Using MaPLES and secoisolariciresinol (a commercially available lignan), the phenolic contents of the maple-derived foods increased 3-fold compared to GAEs. Therefore, lignan-based standards are more appropriate for phenolic quantification of maple-derived foods versus GAEs. Also, MaPLES can be utilized for the authentication and detection of fake label claims on maple products.

  11. Relationships between Community Level Functional Traits of Trees and Seedlings during Secondary Succession in a Tropical Lowland Rainforest.

    Science.gov (United States)

    Lu, XingHui; Zang, RunGuo; Huang, JiHong

    2015-01-01

    Most of the previous studies on functional traits focus exclusively on either seedlings or trees. Little knowledge exists on the relationships between community level functional traits of trees and seedlings during succession. Here, we examine variations of the community-level functional traits for trees and seedlings and their correlations along a secondary successional and environmental gradient in a tropical lowland rainforest after shifting cultivation. The results showed that the dynamic patterns in community level functional traits of seedlings were generally consistent with those of the trees during secondary succession. Compared with seedlings, community level traits for trees were less affected by abiotic factors during secondary succession. Correlations between community level functional traits of trees and seedlings were significant for: leaf dry matter content and leaf nitrogen concentration in the 18-year-old fallow; leaf chlorophyll content in the 30-year-old fallow; specific leaf area, leaf dry matter content and leaf nitrogen concentration in the 60-year-old fallow; and leaf nitrogen concentration in old growth. However, these traits except specific leaf area for the tree and seedling communities were all significantly correlated if all the successional stages were combined. Our results suggest that the correlations between community level functional traits of trees and those of seedlings depend on the actual traits and the successional stages examined. However, if all the four successional stages are combined, then four out of five of the community level functional traits for trees could be well predicted by those of the seedlings in the tropical lowland rain forest.

  12. Identifying critical recruitment bottlenecks limiting seedling establishment in a degraded seagrass ecosystem.

    Science.gov (United States)

    Statton, John; Montoya, Leonardo R; Orth, Robert J; Dixon, Kingsley W; Kendrick, Gary A

    2017-11-01

    Identifying early life-stage transitions limiting seagrass recruitment could improve our ability to target demographic processes most responsive to management. Here we determine the magnitude of life-stage transitions along gradients in physical disturbance limiting seedling establishment for the marine angiosperm, Posidonia australis. Transition matrix models and sensitivity analyses were used to identify which transitions were critical for successful seedling establishment during the first year of seed recruitment and projection models were used to predict the most appropriate environments and seeding densities. Total survival probability of seedlings was low (0.001), however, transition probabilities between life-stages differed across the environmental gradients; seedling recruitment was affected by grazing and bioturbation prevailing during the first life-stage transition (1 month), and 4-6 months later during the third life-stage transition when establishing seedlings are physically removed by winter storms. Models projecting population growth from different starting seed densities showed that seeds could replace other more labour intensive and costly methods, such as transplanting adult shoots, if disturbances are moderated sufficiently and if large numbers of seed can be collected in sufficient quantity and delivered to restoration sites efficiently. These outcomes suggest that by improving management of early demographic processes, we could increase recruitment in restoration programs.

  13. Morphological Diversity of Fruits, Seeds and Seedlings of Pongamia (Pongamia pinnata (L. Pierre in Java Island

    Directory of Open Access Journals (Sweden)

    NFN Supriyanto

    2017-12-01

    Full Text Available Pongamia (Pongamia pinnata (L. Pierre is one of a potential tree species to produce biodiesel. Pongamia-based biodiesel development program is still constrained by the availability of quality and quantity seeds due to the limited of seed sources. The purpose of this research was to identify the morphological diversity of fruits, seeds and seedlings from 5 populations in Java Island. Randomized completely design and randomized block design were used to assess the difference of fruits, seeds and seedlings morphological characteristics among populations. Principal component and hierarchy cluster analysis were used to explain variation pattern among populations. The results showed that the difference of populations was significantly affected by the difference of fruits, seeds, and seedlings morphology of pongamia. Seeds from Carita population showed good quality seed indicators with moisture content of 19.31%, and germination capacity of 74.50%. Sturdiness quotient of the seedling was 10.78. Contribution of genetic factor was higher than environtment factor is relation to the differences of morphological characteristics of fruits, seeds and seedlings of pongamia. Morphological character of the five populations can be divided into 3 groups, i.e. the first group of Batukaras and Kebumen, second group of Alas Purwo and Baluran, and group 3 was Carita.

  14. Effect of a longitudinally applied voltage upon the growth of Zea mays seedlings

    Science.gov (United States)

    Desrosiers, M. F.; Bandurski, R. S.

    1988-01-01

    The electrical parameters that affect young seedling growth were investigated. Voltages ranging from 5 to 40 volts were applied longitudinally along the mesocotyl region of 4-day old Zea mays L. (cv Silver Queen) seedlings for periods of 3 or 4 hours. It was determined that: (a) making the tips of the seedlings electrically positive relative to the base strongly inhibited shoot growth at 5 volts, whereas the reverse polarity had no effect; (b) at higher voltages, making the tip of the seedlings negative caused less growth inhibition than the reverse polarity at each voltage level; (c) the higher the applied voltage the greater the degree of inhibition; and, (d) the more growth inhibition experienced by the plants the poorer, and slower, their recovery. Previous observations of a relationship between the amount of free indole-3-acetic acid in the mesocotyl cortex and the growth rate of the mesocotyl and of gravitropism-induced movement of labeled indole-3-acetic acid from the seed to the shoot lead to the prediction of a voltage-dependent gating of the movement of indole-3-acetic acid from the stele to the cortex. This provided the basis for attempting to alter the growth rate of seedlings by means of an applied voltage.

  15. Germination and Seedling Development of Seeds from Different Parkia biglobosa (Jacq G. Don Trees

    Directory of Open Access Journals (Sweden)

    Christiana O. ADEYEMI

    2013-02-01

    Full Text Available The effect of daylight, continuous illumination and acid scarification on the seed germination and seedling vegetative growth (epicotyl and hypocotyl lengths, and number of secondary roots of different Parkia biglobosawere investigated in the Plant Physiology Laboratory University of Ilorin, Ilorin Kwara State Nigeria. Seeds from two out of the twenty six Parkia tree samples (trees B and T germinated within 24 hours of planting in the daylight germination study while seeds from another tree (Q did not germinate until the third week after planting (3WAP. Some seeds have higher germination percentage both in the daylight (preliminary germination study and in the continuous light (illuminated study. The treatment with concentrated Sulphric acid (conc. H2SO4was effective in breaking the seed dormancy as seeds from eight (8 trees produced one hundred percent (100% germination. At p= 0.05 the length of epicotyl and hypocoty1 lengths were significantly different as seedling vegetative growth were long in the seedlings from the daylight experiment than the continuous light experiment. The vegetative growths of the seedlings from the scarified seed were longer at 15min of scarification in all except in trees F and Z. It was observed that the time of scarification affect the both seed germination and seedling development.

  16. Climate change alters seedling emergence and establishment in an old-field ecosystem.

    Directory of Open Access Journals (Sweden)

    Aimée T Classen

    2010-10-01

    Full Text Available Ecological succession drives large-scale changes in ecosystem composition over time, but the mechanisms whereby climatic change might alter succession remain unresolved. Here, we asked if the effects of atmospheric and climatic change would alter tree seedling emergence and establishment in an old-field ecosystem, recognizing that small shifts in rates of seedling emergence and establishment of different species may have long-term repercussions on the transition of fields to forests in the future.We introduced seeds from three early successional tree species into constructed old-field plant communities that had been subjected for 4 years to altered temperature, precipitation, and atmospheric CO(2 regimes in an experimental facility. Our experiment revealed that different combinations of atmospheric CO(2 concentration, air temperature, and soil moisture altered seedling emergence and establishment. Treatments directly and indirectly affected soil moisture, which was the best predictor of seedling establishment, though treatment effects differed among species.The observed impacts, coupled with variations in the timing of seed arrival, are demonstrated as predictors of seedling emergence and establishment in ecosystems under global change.

  17. Facilitation and interference of seedling establishment by a native legume before and after wildfire.

    Science.gov (United States)

    Goergen, Erin; Chambers, Jeanne C

    2012-01-01

    In semi-arid ecosystems, heterogeneous resources can lead to variable seedling recruitment. Existing vegetation can influence seedling establishment by modifying the resource and physical environment. We asked how a native legume, Lupinus argenteus, modifies microenvironments in unburned and burned sagebrush steppe, and if L. argenteus presence facilitates seedling establishment of native species and the non-native annual grass, Bromus tectorum. Field treatments examined mechanisms by which L. argenteus likely influences establishment: (1) live L. argenteus; (2) dead L. argenteus; (3) no L. argenteus; (4) no L. argenteus with L. argenteus litter; (5) no L. argenteus with inert litter; and (6) mock L. argenteus. Response variables included soil nitrogen, moisture, temperature, solar radiation, and seedling establishment of the natives Elymus multisetus and Eriogonum umbellatum, and non-native B. tectorum. In both unburned and burned communities, there was higher spring soil moisture, increased shade and reduced maximum temperatures under L. argenteus canopies. Adult L. argenteus resulted in greater amounts of soil nitrogen (N) only in burned sagebrush steppe, but L. argenteus litter increased soil N under both unburned and burned conditions. Although L. argenteus negatively affected emergence and survival of B. tectorum overall, its presence increased B. tectorum biomass and reproduction in unburned plots. However, L. argenteus had positive facilitative effects on size and survival of E. multisetus in both unburned and burned plots. Our study indicates that L. argenteus can facilitate seedling establishment in semi-arid systems, but net effects depend on the species examined, traits measured, and level of abiotic stress.

  18. GROWTH AND NODULATION OF LEUCAENA AND PROSOPIS SEEDLINGS IN SOIL PLUS TANNERY SLUDGE

    Directory of Open Access Journals (Sweden)

    Ademir Sérgio Ferreira de Araújo

    2006-01-01

    Full Text Available The objective of this paper was to evaluate the growth and nodulation of Leucaena and Prosopis seedlings in soil plus tannery sludge. The study was conducted in a greenhouse, using bags containing soil plus tannery sludge. Seedlings of Leucaena and Prosopis inoculated with Bradyrhizobium sp were used. Results were evaluated 90 days after plant emergency. The application of tannery sludge, in the rate of 11.250 kg per hectare significantly increased plant height, stem diameter, and above ground dry mass ofLeucaena. Regarding Prosopis, there were no significant increases in these variables with tannery sludge application, except for aerial dry mass. No significant differences were seen between the treatments with sludge and inoculated with Bradyrhizobium sp. as to nodule number and dry mass. Tannery sludge evaluated in this work did not affect nodulation, besides favoring Leucaena and Prosopis seedling growth.

  19. Synergistic effects of altered salinity and temperature on estuarine eelgrass (Zostera marina) seedlings and clonal shoots

    DEFF Research Database (Denmark)

    Salo, Tiina Elina; Pedersen, Morten Foldager

    2014-01-01

    investigated experimentally how different combinations of salinity and temperature affect the physiological performance of adult eelgrass (Zostera marina) shoots and seedlings. Plants were exposed to different combinations of salinity (salinity 5, 12.5 and 20) and temperature (15, 20 and 25 °C) in a 5-week...... and temperature. Seedlings had higher absolute mortality, while adult shoots were relatively more sensitive to unfavorable levels of salinity. Leaf tissue sucrose concentrations in both life stages decreased at low salinity, whereas salinity and temperature resulted in contrasting starch concentrations between...... seedlings and adult shoots. Our results show that altered salinity and temperature may have negative synergistic effects on eelgrass performance. Future climate changes may thus have serious impacts on eelgrass survival and performance....

  20. ADAPTABILITY OF WHITE JABON (Anthocephalus cadamba Miq. SEEDLING FROM 12 POPULATIONS TO DROUGHT AND WATERLOGGING

    Directory of Open Access Journals (Sweden)

    Dede J. Sudrajat

    2015-06-01

    Full Text Available The study was carried out for investigation of the adaptability of white jabon seedlings from 12 populations to drought and water logging stresses in a controlled green house. The results showed that the adaptive responses of white jabon seedling to drought and waterlogging stresses were affected by genotype (population. The drought and waterlogging stresses significantly inhibited plant growth, biomass accumulation and allocation, leaf area, also decreased chlorophyll content, increased carotenoids contents, and accumulated free proline. Relative water content and specific leaf area tended to be higher in waterlogging and declined in drought stresses. The result clearly indicated that white jabon seedlings were more adaptive to waterlogging than to drought stresses. Moreover, there were different responses to drought and waterlogging stresses between the twelve populations. Kampar, Gowa, Kuala Kencana and OKI populations exhibited higher growth performance and stress tolerance index to be adapted to waterlogging stress, while Gowa, Pomalaa and Kampar populations had relatively better growth performance in the drought stress.

  1. Adult trees cause density-dependent mortality in conspecific seedlings by regulating the frequency of pathogenic soil fungi.

    Science.gov (United States)

    Liang, Minxia; Liu, Xubing; Gilbert, Gregory S; Zheng, Yi; Luo, Shan; Huang, Fengmin; Yu, Shixiao

    2016-12-01

    Negative density-dependent seedling mortality has been widely detected in tropical, subtropical and temperate forests, with soil pathogens as a major driver. Here we investigated how host density affects the composition of soil pathogen communities and consequently influences the strength of plant-soil feedbacks. In field censuses of six 1-ha permanent plots, we found that survival was much lower for newly germinated seedlings that were surrounded by more conspecific adults. The relative abundance of pathogenic fungi in soil increased with increasing conspecific tree density for five of nine tree species; more soil pathogens accumulated around roots where adult tree density was higher, and this greater pathogen frequency was associated with lower seedling survival. Our findings show how tree density influences populations of soil pathogens, which creates plant-soil feedbacks that contribute to community-level and population-level compensatory trends in seedling survival. © 2016 John Wiley & Sons Ltd/CNRS.

  2. Winter climate change and fine root biogenic silica in sugar maple trees (Acer saccharum): Implications for silica in the Anthropocene

    Science.gov (United States)

    Maguire, Timothy J.; Templer, Pamela H.; Battles, John J.; Fulweiler, Robinson W.

    2017-03-01

    Winter temperatures are projected to increase over the next century, leading to reductions in winter snowpack and increased frequency of soil freezing in many northern forest ecosystems. Here we examine biogenic silica (BSi) concentrations in sugar maple (Acer saccharum) fine roots collected from a snow manipulation experiment at Hubbard Brook Experimental Forest (New Hampshire, USA). Increased soil freezing significantly lowered the BSi content of sugar maple fine roots potentially decreasing their capacity to take up water and dissolved nutrients. The reduced silica uptake (8 ± 1 kmol silica km-2) by sugar maple fine roots is comparable to silica export from temperate forest watersheds. We estimate that fine roots account for 29% of sugar maple BSi, despite accounting for only 4% of their biomass. These results suggest that increased frequency of soil freezing will reduce silica uptake by temperate tree roots, thereby changing silica availability in downstream receiving waters.

  3. The Evolutionary History of MAPL (Mitochondria-Associated Protein Ligase and Other Eukaryotic BAM/GIDE Domain Proteins.

    Directory of Open Access Journals (Sweden)

    Jeremy G Wideman

    Full Text Available MAPL (mitochondria-associated protein ligase, also called MULAN/GIDE/MUL1 is a multifunctional mitochondrial outer membrane protein found in human cells that contains a unique BAM (beside a membrane domain and a C-terminal RING-finger domain. MAPL has been implicated in several processes that occur in animal cells such as NF-kB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. Previous studies demonstrated that the BAM domain is present in diverse organisms in which most of these processes do not occur, including plants, archaea, and bacteria. Thus the conserved function of MAPL and its BAM domain remains an open question. In order to gain insight into its conserved function, we investigated the evolutionary origins of MAPL by searching for homologues in predicted proteomes of diverse eukaryotes. We show that MAPL proteins with a conserved BAM-RING architecture are present in most animals, protists closely related to animals, a single species of fungus, and several multicellular plants and related green algae. Phylogenetic analysis demonstrated that eukaryotic MAPL proteins originate from a common ancestor and not from independent horizontal gene transfers from bacteria. We also determined that two independent duplications of MAPL occurred, one at the base of multicellular plants and another at the base of vertebrates. Although no other eukaryote genome examined contained a verifiable MAPL orthologue, BAM domain-containing proteins were identified in the protists Bigelowiella natans and Ectocarpus siliculosis. Phylogenetic analyses demonstrated that these proteins are more closely related to prokaryotic BAM proteins and therefore likely arose from independent horizontal gene transfers from bacteria. We conclude that MAPL proteins with BAM-RING architectures have been present in the holozoan and viridiplantae lineages since their very beginnings

  4. Effects of seed and seedling predation by small mammals on ...

    African Journals Online (AJOL)

    Seed predation reduced seedling recruitment from seeds planted in March 1986 in mature fynbos, but ... Seed predation did not significantly reduce seedling recruitment from seed planted in July, August and ... AJOL African Journals Online.

  5. Effect of chromium toxicity on germination and early seedling growth ...

    African Journals Online (AJOL)

    USER

    2010-07-19

    Jul 19, 2010 ... germination and early seedling growth of melon (Cucumis melo L.). Chromium ... chromium on seed germination and seedling growth- biomass in early ..... such critical regulatory mechanisms are likely to operate in seeds at ...

  6. Growth, Physiological, Biochemical, and Ionic Responses of Morus alba L. Seedlings to Various Salinity Levels

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2017-12-01

    Full Text Available Mulberry (Morus alba L., a moderately salt-tolerant tree species, is considered to be economically important. In this study, 1-year-old mulberry seedlings cultivated in soil under greenhouse conditions were treated with five concentrations of sodium chloride (NaCl; 0%, 0.1%, 0.2%, 0.3%, and 0.5% for 3 and 21 days. Plant growth parameters were not affected by 0.1% NaCl, but significant reductions were observed after treatment with 0.2%, 0.3%, and 0.5% NaCl. The malondialdehyde content and cell membrane stability of mulberry seedlings exposed to 0.1% NaCl did not change, indicating that mulberry is not significantly affected by low-salinity conditions. The Na contents of various organs did not increase significantly in response to 0.1% NaCl, but the K:Na, Mg:Na, and Ca:Na ratios of various organs were affected by NaCl. Marked changes in the levels of major compatible solutes (proline, soluble sugars, and soluble proteins occurred in both the leaves and roots of NaCl-treated seedlings relative to control seedlings. Under severe saline conditions (0.5% NaCl, the ability of mulberry to synthesize enzymatic antioxidants may be impaired.

  7. IMPROVED METHODS OF OBTAINING PEPPER SEEDLINGS

    OpenAIRE

    Florina Uleanu

    2012-01-01

    This paper refers to the effect of different types of pots on the level of growth and development of the pepper seedlings in order to clarify the influences caused by use of different recipes transplanters pots. Different biocomposites from renewable resources biodegradable nutritive support were studied. Seedlings were grown in 4 variants of pots M1 (V1), M2 (V2), M3 (V3) and jiffy- pots (V4). The height of the aerial part varied from 14.5 (V1) to 17.4 cm (V4), whereas the root length varied...

  8. The fungi causin damping-off of carrot seedlings

    Directory of Open Access Journals (Sweden)

    Bogdan Nowicki

    2013-12-01

    Full Text Available When 136 samples of dying carrot seedlings from several fields were analyzed Alternaria rudicina proved to be the most common seedling pathogen (41%, followed by some Fusarium species (27%, mostly F. avenaceum.The less common seedling pathogens were Pythium spp. (13%, Phoma spp.(2,5% and Botrytis cinerea (1,4%. Some other fungi (Bipolaris sorokiniana, Sclerotinia sclerotiorum, Stemphylium botryosym and Ulocladium consortiale were found in less than 1% of seedlings examined.

  9. Relative resistance or susceptibility of maple (Acer) species, hybrids and cultivars to six arthropod pests of production nurseries.

    Science.gov (United States)

    Seagraves, Bonny L; Redmond, Carl T; Potter, Daniel A

    2013-01-01

    Maples (Acer spp.) in production nurseries are vulnerable to numerous arthropod pests that can stunt or even kill the young trees. Seventeen cultivars representing various Acer species and hybrids were evaluated for extent of infestation or injury by shoot and trunk borers (Proteoteras aesculana, Chrysobothris femorata), potato leafhopper (Empoasca fabae), Japanese beetle (Popillia japonica), maple spider mite (Oligonychus aceris) and calico scale (Eulecanium cerasorum). Evaluations were done in replicated field plots in central and western Kentucky. All of the maples were susceptible, to varying degrees, to one or more key pest(s). Red maples (A. rubrum) were relatively vulnerable to potato leafhopper injury and borers but nearly free of Japanese beetle feeding and spider mites. Sugar maples sustained conspicuous Japanese beetle damage but had very low mite populations, whereas the opposite was true for Freeman maples (A. × freemanii). A. campestre was heavily infested by calico scale. Within each species or hybrid there were cultivar differences in degree of infestation or damage by particular pests. The results should help growers to focus pest management efforts on those plantings at greatest risk from particular pests, and to choose cultivars requiring fewer insecticide inputs to produce a quality tree. Copyright © 2012 Society of Chemical Industry.

  10. Effects of gravel mulch on emergence of galleta grass seedlings

    International Nuclear Information System (INIS)

    Winkel, V.K.; Medrano, J.C.; Stanley, C.; Walo, M.D.

    1993-03-01

    The Department of Energy Nevada Operations Office, Technology Development and Program Management Division, has identified the need to clean up several sites on the Nevada Test Site and Tonopah Test Range contaminated with surface plutonium. An important objective of the project identified as the Plutonium In Soils Integrated Demonstration is to develop technologies to stabilize and restore the disturbed sites after decontamination. Revegetation of these contaminated sites will be difficult due to their location in the arid Mojave and Great Basin Deserts. The major factors which will affect successful plant establishment and growth at these sites are limited and sporadic precipitation, limited soil water, extreme air and soil temperatures, limited topsoil, and herbivory . Research has shown that providing microsites for seed via mulching can aid in plant emergence and establishment. Since many of the soils at the sites slated for plutonium decontamination have a large percentage of gravel in the upper 10 cm of soil, the use of gravel as mulch could provide microsites for seed and stabilize soils during subsequent revegetation of the sites. In July 1992, EG ampersand G/EM Environmental Sciences Department initiated a greenhouse study to examine the possible benefits of gravel mulch. The specific objectives of this greenhouse study were to: (1) determine the effects seedling emergence and soil water, and (2) determine effects of irrigation rates on seedling emergence for gravel mulches and other conventional seedbed preparation techniques. A secondary objective was to determine the depth of gravel mulch that was optimal for seedling emergence. Results from this greenhouse study will assist in formulating specific reclamation plans for sites chosen for cleanup

  11. Phylogenetic and Functional Diversity of Fleshy-Fruited Plants Are Positively Associated with Seedling Diversity in a Tropical Montane Forest

    Directory of Open Access Journals (Sweden)

    Marcia C. Muñoz

    2017-08-01

    Full Text Available Mutualistic interactions between plants and animals can affect both plant and animal communities, and potentially leave imprints on plant demography. Yet, no study has simultaneously tested how trait variation in plant resources shapes the diversity of animal consumers, and how these interactions influence seedling recruitment. Here, we analyzed whether (i phylogenetic diversity and functional diversity of fruiting plants were correlated with the corresponding diversity of frugivorous birds, and (ii whether phylogenetic diversity and functional identity of plant and bird communities influenced the corresponding diversity and identity of seedling communities. We recorded mutualistic interactions between fleshy-fruited plants and frugivorous birds and seedling communities in 10 plots along an elevational gradient in the Colombian Andes. We built a phylogeny for plants/seedlings and birds and measured relevant morphological plant and bird traits that influence plant-bird interactions and seedling recruitment. We found that phylogenetic diversity and functional diversity of frugivorous birds were positively associated with the corresponding diversities of fruiting plants, consistent with a bottom-up effect of plants on birds. Moreover, the phylogenetic diversity of seedlings was related to the phylogenetic diversity of plants, but was unrelated to the phylogenetic diversity of frugivorous birds, suggesting that top-down effects of animals on seedlings were weak. Mean seed mass of seedling communities was positively associated with the mean fruit mass of plants, but was not associated with the mean avian body mass in the frugivore communities. Our study shows that variation in the traits of fleshy-fruited plants was associated with the diversity of frugivorous birds and affected the future trajectory of seedling recruitment, whereas the morphological traits of animal seed dispersers were unrelated to the phylogenetic and functional structure of

  12. Grazing on Regeneration Sites Encourages Pine Seedling Growth

    Science.gov (United States)

    Raymond D. Ratliff; Renee G. Denton

    1995-01-01

    Effects of season-long, deferred-rotation, and rest-rotation grazing, on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedling growth and herbaceous vegetation control were studied in regeneration sites at Boyd Hill, Modoc National Forest, California. Seedlings were planted in 1989. Pine seedling survival and damage did not differ, but the...

  13. Containers of Attalea funifera fibers to produce eucalyptus seedlings

    Directory of Open Access Journals (Sweden)

    Andrea Vita Reis Mendonça

    2016-09-01

    Full Text Available The aim of this study was to assess the technical feasibility of using biodegradable containers made of fiber waste of Attalea funifera Martius to produce seedling of Eucalyptus camaldulensis Dehnh. The work was carried out in three stages: manufacture of piassava fiber containers, seedling production and field simulation. The experiment of seedling production was in completely randomized design, with two treatments (polyethylene tube and biodegradable container and 10 repetitions, with 64 seedlings per repetition. After 93 days, seedlings were evaluated based on quality variables. The simuation of initial growth of seedlings in the field consisted in planting seedlings in containers of 11L, in completely randomized design, with three treatments: seedlings produced in polyethylene tubes; seedlings produced in biodegradable containers, without removal of the container during planting; and seedlings produced in biodegradable containers, with removal of the container at planting, with ten repetitions, with one seedling by repetition. The biodegradable container withstood the production cycle and resulted in seedlings within acceptable standards quality. The use of biodegradable container, made of palm fibers, waived the removal of this vessel in the final planting.

  14. Production of cell wall enzymes in pepper seedlings, inoculated with ...

    African Journals Online (AJOL)

    Pepper seedlings inoculated with arbuscular mycorrhizal AM fungus, Glomus etunicatum, produced cellulase, polygal-acturonase and pectin methylestrase enzymes. The activities of the enzymes increased as the pepper seedlings matured in age, showing that the activity of the enzymes in the seedlings was age mediated.

  15. Tree seedling response to LED spectra: Implications for forest restoration

    Science.gov (United States)

    Antonio Montagnoli; R. Kasten Dumroese; Mattia Terzaghi; Jeremiah R. Pinto; Nicoletta Fulgaro; Gabriella Stefania Scippa; Donato Chiatante

    2018-01-01

    We found that different spectra, provided by light-emitting diodes or a fluorescent lamp, caused different photomorphological responses depending on tree seedling type (coniferous or broad-leaved), species, seedling development stage, and seedling fraction (shoot or root). For two conifers (Picea abies and Pinus sylvestris) soon after germination (≤40 days), more...

  16. Effect of litter, leaf cover and cover of basal internodes of the dominant species Molinia caerulea on seedling recruitment and established vegetation

    Science.gov (United States)

    Janeček, Štěpán; Lepš, Jan

    2005-09-01

    The effects of litter removal, leaf cover of established plants and cover of basal internodes of a dominant species Molinia caerulea on seedling germination and the dynamics of established plants were studied in a field experiment in an oligotrophic wet meadow. Although the negative influence of litter on total seedling number and seedling species composition was non-significant, litter significantly affected the dynamics of the established vegetation and caused inhibition of total leaf cover development. The effects of total leaf cover of established plants on seedling establishment changed during the vegetation season. Whereas the effect of total leaf cover was positive at the start and in the middle of the vegetation season, at the end the total leaf cover negatively affected seedling establishment. Both total leaf cover and cover of basal internodes affected seedling composition. Effects of these two variables were statistically separable suggesting that they are based on different mechanisms. The response of seedling establishment to these factors was species specific and, consequently, our data support the hypothesis that that biotically generated spatial heterogeneity can promote species co-existence through the differentiation of species regeneration niches.

  17. Observation of Computer-Supported, Collaborative Work Tool Usage during Briefing and Debriefing Phases of Coalition Mission Training Research for Maple Skies

    National Research Council Canada - National Science Library

    Bennett, Jeff; Lamoureux, T. M

    2006-01-01

    .... The opportunity was taken to conduct a video analysis and questionnaire survey of participants in a distributed briefing and debriefing environment during the Maple Skies simulation training event...

  18. Ultra-fast liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry for the rapid phenolic profiling of red maple (Acer rubrum) leaves.

    Science.gov (United States)

    Li, Chunting; Seeram, Navindra P

    2018-03-07

    The red maple (Acer rubrum) species is economically important to North America because of its sap, which is used to produce maple syrup. In addition, various other red maple plant parts, including leaves, were used as a traditional medicine by the Native Americans. Currently, red maple leaves are being used for nutraceutical and cosmetic applications but there are no published analytical methods for comprehensive phytochemical characterization of this material. Herein, a rapid and sensitive method using liquid chromatography with electrospray ionization time-of-flight tandem mass spectrometry was developed to characterize the phenolics in a methanol extract of red maple leaves and a proprietary phenolic-enriched red maple leaves extract (Maplifa™). Time-of-flight mass spectrometry and tandem mass spectrometry experiments led to the identification of 106 phenolic compounds in red maples leaves with the vast majority of these compounds also detected in Maplifa™. The compounds included 68 gallotannins, 25 flavonoids, gallic acid, quinic acid, catechin, epicatechin, and nine other gallic acid derivatives among which 11 are potentially new and 75 are being reported from red maple for the first time. The developed method to characterize red maple leaves phenolics is rapid and highly sensitive and could aid in future standardization and quality control of this botanical ingredient. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Polyembryony and identification of Volkamerian lemon zygotic and nucellar seedlings using RAPD Poliembrionia e identificação de seedlings zigóticos e nucelares de limão volkameriano com RAPD

    Directory of Open Access Journals (Sweden)

    María Andrade-Rodríguez

    2004-06-01

    Full Text Available The objectives of this work were to evaluate the frequency of polyembryony, and to identify zygotic and nucellar seedlings of Citrus volkameriana using RAPD. Twenty-five polyembryonic and eight monoembryonic seeds were cultivated in vitrofor six months. DNA from seedlings was extracted and used in combination with five RAPD primers to identify zygotic or nucellar origin of the seedlings. Environmental conditions of the year affected significantly (POs objetivos deste trabalho foram avaliar a freqüência da poliembrionia e indentificar os seedlings zigóticos e nucelares de Citrus volkameriana usando RAPD. Cultivaram-se in vitro 25 sementes poliembriônicas e 8 monoembriônicas, por seis meses. Extraiu-se o DNA dos seedlings e usou-se em combinação com cinco primers RAPD para identificar a origem zigótica e nucelar das plântulas. Os resultados mostraram que as condições ambientais do ano afetaram significativamente (P<0,05 as características morfológicas dos frutos e o número de embriões por semente. Os índices de sementes poliembriônicas variaram nos três anos de avaliação (30,9%, 44,8% e 54,4%. As características morfológicas não se correlacionaram com a poliembrionia. A cultura in vitro possibilita que todos os embriões de cada semente cresçam, favorecendo os seedlings identificados como zigóticos. Nas sementes poliembriônicas e monoembriônicas, 25,9% e 87,5% dos seedlings, respectivamente, originaram-se sexualmente. Nem todos os seedlings zigóticos foram produzidos por embriões localizados no micrófilo das sementes poliembriônicas.

  20. Proton magnetic resonance spectroscopy reflects metabolic decompensation in maple syrup urine disease

    Energy Technology Data Exchange (ETDEWEB)

    Heindel, W. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany); Kugel, H. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany); Wendel, U. [Children`s Hospital, Univ. Duesseldorf (Germany); Roth, B. [Children`s Hospital, Univ. Koeln (Germany); Benz-Bohm, G. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany)

    1995-06-01

    Using localized proton magnetic resonance spectroscopy ({sup 1}H-MRS), accumulation of branchedchain amino acids (BCAA) and their corresponding 2-oxo acids (BCOA) could be non-invasively demonstrated in the brain of a 9-year-old girl suffering from classical maple syrup urine disease. During acute metabolic decompensation, the compounds caused a signal at a chemical shift of 0.9 ppm which was assigned by in vitro experiments. The brain tissue concentration of the sum of BCAA and BCOA could be estimated as 0.9 mmol/l. Localized {sup 1}H-MRS of the brain appears to be suitable for examining patients suffering from maple syrup urine disease in different metabolic states. (orig.)

  1. Optics learning by computing, with examples using Maple, MathCad, Mathematica, and MATLAB

    CERN Document Server

    Moeller, Karl Dieter

    2007-01-01

    This new edition is intended for a one semester course in optics for juniors and seniors in science and engineering; it uses scripts from Maple, MathCad, Mathematica, and MATLAB provide a simulated laboratory where students can learn by exploration and discovery instead of passive absorption. The text covers all the standard topics of a traditional optics course, including: geometrical optics and aberration, interference and diffraction, coherence, Maxwell's equations, wave guides and propagating modes, blackbody radiation, atomic emission and lasers, optical properties of materials, Fourier transforms and FT spectroscopy, image formation, and holography. It contains step by step derivations of all basic formulas in geometrical, wave and Fourier optics. The basic text is supplemented by over 170 files in Maple, MathCad, Mathematica, and MATLAB (many of which are in the text, each suggesting programs to solve a particular problem, and each linked to a topic in or application of optics. The computer files are d...

  2. Maple Syrup Decreases TDP-43 Proteotoxicity in a Caenorhabditis elegans Model of Amyotrophic Lateral Sclerosis (ALS).

    Science.gov (United States)

    Aaron, Catherine; Beaudry, Gabrielle; Parker, J Alex; Therrien, Martine

    2016-05-04

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease causing death of the motor neurons. Proteotoxicity caused by TDP-43 protein is an important aspect of ALS pathogenesis, with TDP-43 being the main constituent of the aggregates found in patients. We have previously tested the effect of different sugars on the proteotoxicity caused by the expression of mutant TDP-43 in Caenorhabditis elegans. Here we tested maple syrup, a natural compound containing many active molecules including sugars and phenols, for neuroprotective activity. Maple syrup decreased several age-dependent phenotypes caused by the expression of TDP-43(A315T) in C. elegans motor neurons and requires the FOXO transcription factor DAF-16 to be effective.

  3. Dosimetry aspects of the new Canadian MAPLE-X10 reactor

    International Nuclear Information System (INIS)

    Lidstone, R.F.; Wilkin, G.B.

    1994-01-01

    Atomic Energy of Canada Limited is building the 10-MW t MAPLE-X10 reactor facility as a dedicated producer of medical and industrial radioisotopes. Dosimetry aspects of the MAPLE-X10 nuclear design include the calculated thermal and fast neutron flux distributions throughout the reactor assembly and the rate of heat generation in reactor materials and components. Examples of the resolution of design issues are also presented, such as the use of fission counters and ion chambers to provide diverse methods of detecting neutron flux levels and the use of the difference between photon and neutron signals to guard against the effects of downgrading of the heavy-water reflector. Computer codes employed in the calculations include MCNP, ONEDANT, WIMS-AECL, and 3DDT

  4. Proton magnetic resonance spectroscopy reflects metabolic decompensation in maple syrup urine disease

    International Nuclear Information System (INIS)

    Heindel, W.; Kugel, H.; Wendel, U.; Roth, B.; Benz-Bohm, G.

    1995-01-01

    Using localized proton magnetic resonance spectroscopy ( 1 H-MRS), accumulation of branchedchain amino acids (BCAA) and their corresponding 2-oxo acids (BCOA) could be non-invasively demonstrated in the brain of a 9-year-old girl suffering from classical maple syrup urine disease. During acute metabolic decompensation, the compounds caused a signal at a chemical shift of 0.9 ppm which was assigned by in vitro experiments. The brain tissue concentration of the sum of BCAA and BCOA could be estimated as 0.9 mmol/l. Localized 1 H-MRS of the brain appears to be suitable for examining patients suffering from maple syrup urine disease in different metabolic states. (orig.)

  5. A Direct Algorithm Maple Package of One-Dimensional Optimal System for Group Invariant Solutions

    Science.gov (United States)

    Zhang, Lin; Han, Zhong; Chen, Yong

    2018-01-01

    To construct the one-dimensional optimal system of finite dimensional Lie algebra automatically, we develop a new Maple package One Optimal System. Meanwhile, we propose a new method to calculate the adjoint transformation matrix and find all the invariants of Lie algebra in spite of Killing form checking possible constraints of each classification. Besides, a new conception called invariance set is raised. Moreover, this Maple package is proved to be more efficiency and precise than before by applying it to some classic examples. Supported by the Global Change Research Program of China under Grant No. 2015CB95390, National Natural Science Foundation of China under Grant Nos. 11675054 and 11435005, and Shanghai Collaborative Innovation Center of Trustworthy Software for Internet of Things under Grant No. ZF1213

  6. Proteome analysis of Norway maple (Acer platanoides L.) seeds dormancy breaking and germination: influence of abscisic and gibberellic acids.

    Science.gov (United States)

    Pawłowski, Tomasz A

    2009-05-04

    Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA) and gibberellic (GA) acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent state to germination. Seed dormancy breaking involves

  7. Proteome analysis of Norway maple (Acer platanoides L. seeds dormancy breaking and germination: influence of abscisic and gibberellic acids

    Directory of Open Access Journals (Sweden)

    Pawłowski Tomasz A

    2009-05-01

    Full Text Available Abstract Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid and growth promoters (e.g. gibberellins is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA and gibberellic (GA acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent

  8. Germination and seedlings performance of cashew ( Anacardium ...

    African Journals Online (AJOL)

    The effects of nut-sowing orientations on the germination of cashew nuts and the responses of the resultant seedlings to cotyledon removed were studied in the nursery. While cashew nuts sown flat and those with stylar-end up had highest mean germination of 91.67 % and 92.50 % respectively the nuts sown with ...

  9. Direct-seedling pines in the south

    Science.gov (United States)

    Harold J. Derr; William F. Mann

    1971-01-01

    Direct seeding of the southern pines is a versatile reforestation technique that is being widely accepted by land managers. On many sites it is more economical than planting nursery-grown seedlings or waiting for natural reproduction. It is applicable on some sites where access, terrain, or drainage conditions make planting difficult. Commercial trials have proved it...

  10. The role of onion-associated fungi in bulb mite infestation and damage to onion seedlings.

    Science.gov (United States)

    Ofek, Tal; Gal, Shira; Inbar, Moshe; Lebiush-Mordechai, Sara; Tsror, Leah; Palevsky, Eric

    2014-04-01

    In Israel Rhizoglyphus robini is considered to be a pest in its own right, even though the mite is usually found in association with fungal pathogens. Plant protection recommendations are therefore to treat germinating onions seedlings, clearly a crucial phase in crop production, when mites are discovered. The aim of this study was to determine the role of fungi in bulb mite infestation and damage to germinating onion seedlings. Accordingly we (1) evaluated the effect of the mite on onion seedling germination and survival without fungi, (2) compared the attraction of the mite to species and isolates of various fungi, (3) assessed the effect of a relatively non-pathogenic isolate of Fusarium oxysporum on mite fecundity, and (4) determined the effects of the mite and of F. oxysporum separately and together, on onion seedling germination and sprout development. A significant reduction of seedling survival was recorded only in the 1,000 mites/pot treatment, after 4 weeks. Mites were attracted to 6 out of 7 collected fungi isolates. Mite fecundity on onion sprouts infested with F. oxysporum was higher than on non-infested sprouts. Survival of seedlings was affected by mites, fungi, and their combination. Sprouts on Petri dishes after 5 days were significantly longer in the control and mite treatments than both fungi treatments. During the 5-day experiment more mites were always found on the fungi-infected sprouts than on the non-infected sprouts. Future research using suppressive soils to suppress soil pathogens and subsequent mite damage is proposed.

  11. Third year effects of cloudwater and ozone on red spruce seedlings

    International Nuclear Information System (INIS)

    Pier, P.A.; Thornton, F.C.; McDuffie, C. Jr.

    1991-01-01

    The reduction in growth of high elevation red spruce in the eastern US has been attributed in part to greater exposure to atmospheric pollution which occurs at high elevation. The authors objective was to evaluate the impact of ambient ozone and cloudwater deposition on the growth of red spruce seedlings at a high elevation site. Potted native and Phyton-grown (Phyton Technologies) red spruce seedlings were exposed in open-top field chambers at Whitetop Mountain, Virginia (elevation 1,680) for the third season to treatments of: (1) exclusion of clouds and 50% reduction in ambient O 3 (COE), (2) O 3 with clouds excluded (CO), (3) exposure to clouds and O 3 , as control chambers (CC), and (4) open plots (AA). Plant biomass components and diameter increment growth for both seedling types were not affected by treatments. Photosynthesis was not enhanced by removal of cloudwater and O 3 . Respiration (R d ) generally was not affected by treatments; however, R d in native seedling needles of previous year and two-year previous growth was significantly greater in CC than CO and COE on several sampling dates, indicating that cloudwater and O 3 may be causing higher R d

  12. Haemodialysis is an effective treatment in acute metabolic decompensation of maple syrup urine disease

    Directory of Open Access Journals (Sweden)

    P.S. Atwal

    2015-09-01

    Full Text Available Acute metabolic decompensation in maple syrup urine disease can occur during intercurrent illness and is a medical emergency. A handful of reports in the medical literature describe the use of peritoneal dialysis and haemodialysis as therapeutic inventions. We report the only patient from our centre to have haemodialysis performed in this setting. Combined with dietary BCAA restriction and calorific support, haemodialysis allows rapid reduction in plasma leucine concentrations considerably faster than conservative methods.

  13. Rooting Depths of Red Maple (Acer Rubrum L.) on Various Sites in the Lake States

    Science.gov (United States)

    Carl L. Haag; James E. Johnson; Gayne G. Erdmann

    1989-01-01

    Rooting depth and habit of red maple were observed on 60 sites in northern Wisconsin and Michigan as part of a regional soil-site studay. Vertical woody root extension on dry, outwash sites averaged 174 cm, which was significantly greater than the extension on sites with fragipans (139 cm) and on wet sites (112 cm). Site index was higher on wet sites and non-woody...

  14. Some applications of linear difference equations in finance with wolfram|alpha and maple

    Directory of Open Access Journals (Sweden)

    Dana Rıhová

    2014-12-01

    Full Text Available The principle objective of this paper is to show how linear difference equations can be applied to solve some issues of financial mathematics. We focus on the area of compound interest and annuities. In both cases we determine appropriate recursive rules, which constitute the first order linear difference equations with constant coefficients, and derive formulas required for calculating examples. Finally, we present possibilities of application of two selected computer algebra systems Wolfram|Alpha and Maple in this mathematical area.

  15. First record in Argentina of Drepanosiphum oregonense Granovsky (Hemiptera: Aphididae) found on maples (Sapindaceae)

    OpenAIRE

    Ortego, Jaime; Olave, Anabel; Mier Durante, Milagros Pilar

    2014-01-01

    Se informa del hallazgo del áfido Drepanosiphum oregonense Granovsky (Hemiptera: Aphididae) sobre árboles de Acer pseudoplatanus y A. campestre (Sapindaceae) en Argentina lo que constituye el primer registro de la especie y del género Drepanosiphum Koch en Argentina y el segundo en Sudamérica. The finding in Argentina of the aphid Drepanosiphum oregonense on "maple tree" Acer pseudoplatanus ...

  16. Thinning cherry-maple stands in West Virginia: 5-year results

    Science.gov (United States)

    Neil I. Lamson; H. Clay. Smith; H. Clay. Smith

    1988-01-01

    In northern West Virginia, 60-year-old cherry-maple stands were thinned to 75,60, and 45 percent relative stand density. Analysis of 5-year growth data showed that basal-area growth was not reduced by thinning. Cubic-foot and board-foot volume growth decreased slightly. Individual-tree growth of all trees, dominant/codominant trees, and the 50 largest diameter trees...

  17. Seasonal changes of cytokinins in upper and lower leaves of a sugar maple crown

    International Nuclear Information System (INIS)

    Held, M.A.; Quesnelle, P.E.; Emery, R.J.N.

    2005-01-01

    Although it is well accepted that cytokinins (CKs) regulate processes such as leaf senescence and stomatal conductance, data on CKs in the canopy of mature trees are lacking in the literature. Here we report the first in situ sampling for determination of CKs in mature sugar maple (Acer saccharum) canopy layers. The upper canopy showed a distinct seasonal pattern in total CK content, whereas the lower canopy remained relatively unchanged

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

    Science.gov (United States)

    Runkle, James R

    2013-05-01

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

  19. A friendly Maple module for one and two group reactor model

    International Nuclear Information System (INIS)

    Baptista, Camila O.; Pavan, Guilherme A.; Braga, Kelmo L.; Silva, Marcelo V.; Pereira, P.G.S.; Werner, Rodrigo; Antunes, Valdir; Vellozo, Sergio O.

    2015-01-01

    The well known two energy groups core reactor design model is revisited. A simple and friendly Maple module was built to cover the steps calculations of a plate reactor in five situations: 1. one group bare reactor, 2. two groups bare reactor, 3. one group reflected reactor, 4. 1-1/2 groups reflected reactor and 5. two groups reflected reactor. The results show the convergent path of critical size, as it should be. (author)

  20. Organic/hybrid thin films deposited by matrix-assisted pulsed laser evaporation (MAPLE)

    Science.gov (United States)

    Stiff-Roberts, Adrienne D.; Ge, Wangyao

    2017-12-01

    Some of the most exciting materials research in the 21st century attempts to resolve the challenge of simulating, synthesizing, and characterizing new materials with unique properties designed from first principles. Achievements in such development for organic and organic-inorganic hybrid materials make them important options for electronic and/or photonic devices because they can impart multi-functionality, flexibility, transparency, and sustainability to emerging systems, such as wearable electronics. Functional organic materials include small molecules, oligomers, and polymers, while hybrid materials include inorganic nanomaterials (such as zero-dimensional quantum dots, one-dimensional carbon nanotubes, or two-dimensional nanosheets) combined with organic matrices. A critically important step to implementing new electronic and photonic devices using such materials is the processing of thin films. While solution-based processing is the most common laboratory technique for organic and hybrid materials, vacuum-based deposition has been critical to the commercialization of organic light emitting diodes based on small molecules, for example. Therefore, it is desirable to explore vacuum-based deposition of organic and hybrid materials that include larger macromolecules, such as polymers. This review article motivates the need for physical vapor deposition of polymeric and hybrid thin films using matrix-assisted pulsed laser evaporation (MAPLE), which is a type of pulsed laser deposition. This review describes the development of variations in the MAPLE technique, discusses the current understanding of laser-target interactions and growth mechanisms for different MAPLE variations, surveys demonstrations of MAPLE-deposited organic and hybrid materials for electronic and photonic devices, and provides a future outlook for the technique.

  1. A friendly Maple module for one and two group reactor model

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Camila O.; Pavan, Guilherme A.; Braga, Kelmo L.; Silva, Marcelo V.; Pereira, P.G.S.; Werner, Rodrigo; Antunes, Valdir; Vellozo, Sergio O., E-mail: camila.oliv.baptista@gmail.com, E-mail: pavanguilherme@gmail.com, E-mail: kelmo.lins@gmail.com, E-mail: marcelovilelasilva@gmail.com, E-mail: rodrigowerner@hotmail.com, E-mail: neutron201566@yahoo.com, E-mail: vellozo@ime.eb.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Departamento de Engenharia Nuclear

    2015-07-01

    The well known two energy groups core reactor design model is revisited. A simple and friendly Maple module was built to cover the steps calculations of a plate reactor in five situations: 1. one group bare reactor, 2. two groups bare reactor, 3. one group reflected reactor, 4. 1-1/2 groups reflected reactor and 5. two groups reflected reactor. The results show the convergent path of critical size, as it should be. (author)

  2. A Maple package for computing Groebner bases for linear recurrence relations

    International Nuclear Information System (INIS)

    Gerdt, Vladimir P.; Robertz, Daniel

    2006-01-01

    A Maple package for computing Groebner bases of linear difference ideals is described. The underlying algorithm is based on Janet and Janet-like monomial divisions associated with finite difference operators. The package can be used, for example, for automatic generation of difference schemes for linear partial differential equations and for reduction of multiloop Feynman integrals. These two possible applications are illustrated by simple examples of the Laplace equation and a one-loop scalar integral of propagator type

  3. A Maple package for computing Groebner bases for linear recurrence relations

    Energy Technology Data Exchange (ETDEWEB)

    Gerdt, Vladimir P. [Laboratory of Information Technologies, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)]. E-mail: gerdt@jinr.ru; Robertz, Daniel [Lehrstuhl B fuer Mathematik, RWTH Aachen, Templergraben 64, D-52062 Aachen (Germany)]. E-mail: daniel@momo.math.rwth-aachen.de

    2006-04-01

    A Maple package for computing Groebner bases of linear difference ideals is described. The underlying algorithm is based on Janet and Janet-like monomial divisions associated with finite difference operators. The package can be used, for example, for automatic generation of difference schemes for linear partial differential equations and for reduction of multiloop Feynman integrals. These two possible applications are illustrated by simple examples of the Laplace equation and a one-loop scalar integral of propagator type.

  4. Effects of crown release on growth and quality of even-aged red maple stands

    Science.gov (United States)

    Terry F. Strong; Audra E. Hubbell; Adam H. Weise; Gayne G. Erdmann

    2006-01-01

    The effects of six crown-release treatments on growth and bole quality of 54 dominant, codominant, and intermediate red maples (Acer rubrum L.) were examined in an even-aged stand in upper Michigan. Treatments included an unreleased control, a single-tree and a two-tree crown release, and a full crown-to-crown release of 5, 10, and 15ft. Twenty-two...

  5. Hardening of eucalyptus seedlings via salicylic acid application

    Directory of Open Access Journals (Sweden)

    Eduardo Henrique Lima Mazzuchelli

    2014-09-01

    Full Text Available The agricultural and forest productivity suffer restrictions imposed by water stress, high temperature and high solar radiation. This study aimed to evaluate the capacity of stress attenuation and growth promotion of salicylic acid (SA application in eucalyptus (E. urophylla x E. grandis hybrid seedlings under water stress. A completely randomized design, in a 3x4 factorial scheme (three water treatments: constant irrigation with daily replacement of 40% (CI40% or 100% (CI100% of evapotranspirated water, and temporary irrigation suspension with replacement of only 40% of evapotranspirated water (S40%; and four SA concentrations: 0 mg L-1, 100 mg L-1, 200 mg L-1 and 300 mg L-1, was used. Plant photosynthetic parameters and biometric features were evaluated. The stomatal limitation was higher in plants under S40% irrigation, however, the SA application reverted this result, allowing the maintenance of the photosynthetic potential. There was interaction between irrigation regimes and SA doses for number of leaves, leaf area/number of leaves ratio and shoot and root dry mass. It was concluded that the application of 200 mg L -1 of SA positively affected the growth of eucalyptus seedlings under water stress, being considered an auxiliary management technique to their hardening process.

  6. Pengaruh Model Pembelajaran Investigasi Kelompok berbantuan Perangkat Lunak Maple terhadap Kemampuan Pemecahan Masalah Matematis

    Directory of Open Access Journals (Sweden)

    Putri Wulandari

    2016-06-01

    Full Text Available This study aims to determine the effect of mathematical problem solving ability of learners who follow the learning by using an instructional model of maple assisted software assisted, with learners who use, study group investigation model, as well as learners who follow the conventional learning model conducted by researchers on participants Students of class X SMK Muhammadiyah 1 Metro. This type of research is a quasi experimental research with posttest only control design design. Hypothesis test using a one-way anava test with unequal cells and obtained the conclusion that the model of group investigation learning is better than an instructional model of maple assisted software group and both models of learning is better than conventional learning model. Based on the results of analysis and discussion of research data obtained that there is an influence on the ability of solving mathematical problems among students in class applying group investigation model assisted maple software, students in class apply only group investigation learning model, and students whose class apply the conventional learning model on the principal Discussion of the matrix.

  7. Tailored biodegradable triblock copolymer coatings obtained by MAPLE: a parametric study

    Science.gov (United States)

    Brajnicov, S.; Neacsu, P.; Moldovan, A.; Marascu, V.; Bonciu, A.; Ion, R.; Dinca, V.; Cimpean, A.; Dinescu, M.

    2017-11-01

    Biocompatible and biodegradable coatings with controllable and tailored chemical and physical characteristics (i.e. morphology and roughness) are of great interest in bone related research applications. Within this research direction, in this work, a series of novel biodegradable coatings based on triblock copolymers poly(lactide- co-caprolactone)-block-poly(ethylene-glycol)-block-poly(lactide- co-caprolactone) (PLCL-PEG-PLCL) were obtained by matrix-assisted pulsed laser evaporation (MAPLE) and their morphological characteristics and roughness were modulated by varying target composition and laser fluence. The coatings were used for preliminary in vitro testing with MC3T3-E1 pre-osteoblasts. It was found that for a specific range of fluences, the main functional groups in the MAPLE-deposited thin films, as determined by Fourier transform infrared spectroscopy, are similar to the molecular structures of the initial material. Depending on the deposition parameters, significant changes in morphologies, i.e. material accumulation in the form of droplets, wrinkles, or carpet-like structures were revealed by atomic force microscopy (AFM) and scanning electron microscopy. The optimized coating characteristics were further correlated to MC3T3-E1 pre-osteoblasts response. The ability to control the morphology and to maintain unaltered the chemistry of the deposited material through MAPLE is an important step in creating functional bio-interfaces in the field of biomedical research and tissue engineering.

  8. RIR MAPLE procedure for deposition of carbon rich Si/C/H films

    International Nuclear Information System (INIS)

    Dřínek, Vladislav; Strašák, Tomáš; Novotný, Filip; Fajgar, Radek; Bastl, Zdeněk

    2014-01-01

    We applied the resonant infrared matrix assisted pulsed laser evaporation (RIR MAPLE) technique to demonstrate a new approach to a controlled deposition of carbon rich amorphous Si/C/H film. In absence of radicals and accelerated species commonly generated in PECVD and sputtering setups, the RIR MAPLE method does not decompose precursor molecules. Moreover, unlike the standard MAPLE procedure, in which solvent molecules absorb laser energy from excimer or near infrared lasers, we applied the pulsed TEA CO 2 laser to excite the dendrimer precursor molecules in a frozen target. In this manner we achieved just cross-linking of the starting precursor on substrates and the deposition of carbon rich Si/C/H film. The film was analyzed by Fourier Transformed Infrared (FTIR), UV/VIS, Raman and X-ray Photoelectron (XPS) spectroscopy and Atomic Force Microscopy (AFM) technique. According to analyses the film retained the precursor elemental composition free of graphitic (sp 2 ) clusters. In course of reaction only the peripheral allyl groups containing C=C bonds were opened to achieve cross-linking. Whereas annealing to 300 °C was necessary for the elimination of =C–H 1 , 2 bonds in the films prepared at 200 °C, those bonds vanished completely for the films prepared at substrate temperature 255 °C. The film posseses a smooth surface with root mean square (RMS) parameter up to 10 nm within scanned distance 2.5 μm.

  9. Morphological and molecular identification of phytophthora species from maple trees in Serbia

    Directory of Open Access Journals (Sweden)

    Milenković Ivan

    2014-01-01

    Full Text Available The paper presents the results of the study performed with aims to determine the presence and diversity of Phytophthora species on maple trees in Serbia. Due to high aggressiveness and their multicyclic nature, presence of these pathogens is posing significant threat to forestry and biodiversity. In total, 29 samples of water, soil and tissues were taken from 10 different localities, and six different maple hosts were tested. After the isolation tests, 17 samples from five different maple hosts were positive for the presence of Phytophthora spp., and 31 isolates were obtained. After the detailed morphological and physiological classification, four distinct groups of isolates were separated. DNA was extracted from selected representative isolates and molecular identification with sequencing of ITS region was performed. Used ITS4 and ITS6 primers successfully amplified the genomic DNA of chosen isolates and morphological identification of obtained isolates was confirmed after the sequencing. Four different Phytophthora species were detected, including P. cactorum, P. gonapodyides, P. plurivora and P. lacustris. The most common isolated species was homothallic, and with very variable and semipapillate sporangia, P. plurivora with 22 obtained isolates. This is the first report of P. plurivora and P. gonapodyides on A. campestre, P. plurivora and P. lacustris on Acer heldreichii and first report of P. lacustris on A. pseudoplatanus and A. tataricum in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008

  10. Early Autumn Senescence in Red Maple (Acer rubrum L.) Is Associated with High Leaf Anthocyanin Content.

    Science.gov (United States)

    Anderson, Rachel; Ryser, Peter

    2015-08-05

    Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L.) over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consistent between the two years of investigation. Autumn anthocyanin content strongly correlated with degree of chlorophyll degradation mid to late September, early senescing leaves having the highest concentrations of anthocyanins. It also correlated positively with leaf summer chlorophyll content and dry matter content, and negatively with specific leaf area. Time of leaf senescence and anthocyanin contents correlated with soil pH and with canopy openness. We conclude that the importance of anthocyanins in protection of leaf processes during senescence depends on the time of senescence. Rather than prolonging the growing season by enabling a delayed senescence, autumn anthocyanins in red maple in Ontario are important when senescence happens early, possibly due to the higher irradiance and greater danger of oxidative damage early in the season.

  11. The development of maple technology for materials testing, isotope production, and neutron-beam applications

    International Nuclear Information System (INIS)

    Lidstone, R.F.; Gillespie, G.E.; Lee, A.G.; Bishop, W.E.

    1996-01-01

    AECL has been developing MAPLE technology to meet Canadian and international requirements for high-performance research reactors. MAPLE refers to a family of open-tank-in-pool reactors that employ compact H 2 O-cooled cores within D 2 O vessels to efficiently furnish neutrons to various types of irradiation facilities. The initial focus was on a 10-MW t Canadian facility for radioisotope production, the HANARO multipurpose-reactor project, and an associated R and D program. Recently, AECL began to develop the concept for a new Canadian Irradiation Research Facility (IRF) which will support the continued evolution of CANDU (CANadian Deuterium Uranium) technology and generate neutrons for basic and applied materials science. Additionally, AECL is currently developing a standardized MAPLE research-centre design with integrated neutron-application facilities; various reactor-core options have been optimized for different combinations of utilization: a 19-site core for neutron-beam applications and ancillary isotope production, a 31-site core for multipurpose materials testing and neutron-beam applications, and twin 18-site cores for high-flux neutron-beam applications. (author)

  12. Computational and experimental study of the cluster size distribution in MAPLE

    International Nuclear Information System (INIS)

    Leveugle, Elodie; Zhigilei, Leonid V.; Sellinger, Aaron; Fitz-Gerald, James M.

    2007-01-01

    A combined experimental and computational study is performed to investigate the origin and characteristics of the surface features observed in SEM images of thin polymer films deposited in matrix-assisted pulsed laser evaporation (MAPLE). Analysis of high-resolution SEM images of surface morphologies of the films deposited at different fluences reveals that the mass distributions of the surface features can be well described by a power-law, Y(N) ∝ N -t , with exponent -t ∼ -1.6. Molecular dynamic simulations of the MAPLE process predict a similar size distribution for large clusters observed in the ablation plume. A weak dependence of the cluster size distributions on fluence and target composition suggests that the power-law cluster size distribution may be a general characteristic of the ablation plume generated as a result of an explosive decomposition of a target region overheated above the limit of its thermodynamic stability. Based on the simulation results, we suggest that the ejection of large matrix-polymer clusters, followed by evaporation of the volatile matrix, is responsible for the formation of the surface features observed in the polymer films deposited in MAPLE experiments

  13. RIR MAPLE procedure for deposition of carbon rich Si/C/H films

    Energy Technology Data Exchange (ETDEWEB)

    Dřínek, Vladislav, E-mail: drinek@icpf.cas.cz [Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojova 135, 165 02 Prague 6 (Czech Republic); Strašák, Tomáš [Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojova 135, 165 02 Prague 6 (Czech Republic); Novotný, Filip [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, 115 19 Prague (Czech Republic); Fajgar, Radek [Institute of Chemical Process Fundamentals of the ASCR, v. v. i., Rozvojova 135, 165 02 Prague 6 (Czech Republic); Bastl, Zdeněk [J. Heyrovsky Institute of Physical Chemistry of the ASCR, v. v. i., Dolejškova 2155/3, 182 23 Prague 8 (Czech Republic)

    2014-02-15

    We applied the resonant infrared matrix assisted pulsed laser evaporation (RIR MAPLE) technique to demonstrate a new approach to a controlled deposition of carbon rich amorphous Si/C/H film. In absence of radicals and accelerated species commonly generated in PECVD and sputtering setups, the RIR MAPLE method does not decompose precursor molecules. Moreover, unlike the standard MAPLE procedure, in which solvent molecules absorb laser energy from excimer or near infrared lasers, we applied the pulsed TEA CO{sub 2} laser to excite the dendrimer precursor molecules in a frozen target. In this manner we achieved just cross-linking of the starting precursor on substrates and the deposition of carbon rich Si/C/H film. The film was analyzed by Fourier Transformed Infrared (FTIR), UV/VIS, Raman and X-ray Photoelectron (XPS) spectroscopy and Atomic Force Microscopy (AFM) technique. According to analyses the film retained the precursor elemental composition free of graphitic (sp{sup 2}) clusters. In course of reaction only the peripheral allyl groups containing C=C bonds were opened to achieve cross-linking. Whereas annealing to 300 °C was necessary for the elimination of =C–H{sub 1}, {sub 2} bonds in the films prepared at 200 °C, those bonds vanished completely for the films prepared at substrate temperature 255 °C. The film posseses a smooth surface with root mean square (RMS) parameter up to 10 nm within scanned distance 2.5 μm.

  14. New Gallotannin and other Phytochemicals from Sycamore Maple (Acer pseudoplatanus) Leaves.

    Science.gov (United States)

    Zhang, Lu; Tu, Zong-cai; Yuan, Tao; Ma, Hang; Niesen, Daniel B; Wang, Hui; Seeram, Navindra P

    2015-11-01

    The maple (Acer) genus is a reported source of bioactive (poly)phenols, including gallotannins, but several of its members, such as the sycamore maple (A. pseudoplatanus), remain uninvestigated. Herein, thirty-nine compounds, including a new gallotannin, 1,2,3-tri-O-galloyl-6-O-(p-hydroxybenzoyl)-β-D- glucopyranoside (1), and thirty-eight (2-39) known compounds, consisting of four gallotannins, one ellagitannin, thirteen flavonoids, eight hydroxycinnamic acids, ten benzoic acid derivatives, and two sesquiterpenoids, were isolated from sycamore maple leaves. Their structures were determined based on NMR and mass spectral analyses. The isolates were evaluated for α-glucosidase inhibitory and antioxidant activities. Among the isolates, the gallotannins were the most potent α-glucosidase inhibitors with thirteen-fold more potent activity compared with the clinical drug, acarbose (IC50 = 16-31 vs. 218 µM). Similarly, the gallotannins showed the highest antioxidant activities, followed by the other phenolic sub-classes, while the sesquiterpenoids were inactive.

  15. Labelling of rice seedlings and rice plants with 32P

    International Nuclear Information System (INIS)

    Achmad Nasroh, K.

    1989-01-01

    Labelling of rice seedlings and rice plants with 32 P. Labelled rice seedlings can be used to tag insect pests that feed on. Radioactivity counting of 32 P in the endosperm and in the shoot of rice seeds that soaked for 72 hours in KH 2 32 PO 4 solution of 1 μCi/ml were 29,300 and 9,500 cpm respectively. When these labelled seedlings were grown in unlabelled medium the radioactivity in the shoot increased. It was due to the 32 P that was translocated to the shoot from the endosperm. The 32 P translocation reached maximum about one week after the seedling were grown in the unlabelled medium. Labelled seedlings could also be produced by growing 5, 10 and 15 days old seedlings hydroponically in Kimura B solution containing 32 P. Ten days after growing, the radioactivity concentration of the seedlings stem reached about 115,000; 85,000 and 170,000 cpm/mg dry weight for the 5, 10 and 15 days old seedlings respectively. For the implementation of this method, 20 ml labelled Kimura B was needed for labelling of one seedling. The seedlings should be prepared in tap water. During the growth the 32 P in the labelled seedlings was distributed throughout the plant, so that new leaves and tillers became also radioactive. (author). 5 refs

  16. Dying piece by piece: carbohydrate dynamics in aspen seedlings under severe carbon stress and starvation

    Science.gov (United States)

    Wiley, Erin; Chow, Pak; Landhäusser, Simon

    2016-04-01

    Carbon stress and starvation remain poorly understood in trees, despite their potential role in mortality from a variety of agents. To explore the effects of carbon stress on nonstructural carbohydrate (NSC) dynamics and recovery potential and to examine the process of starvation, we grew aspen seedlings under one of three levels of shade: 40% (light shade), 8% (medium shade), and 4% (dark shade) of full sunlight. We then exposed seedlings to 24 hours darkness at either 20° or 28° C until trees had died. Periodically, seedlings were harvested for NSC analysis and to measure stem and root respiration. In addition, some seedlings were moved back into the light to determine if recovery was possible at certain points during starvation. Specifically, we sought to address the following questions: 1) Do NSC concentrations or mass influence tree survival under carbon stress? 2) At what carbohydrate levels do trees fail to recover and starve? 3) Does temperature affect the NSC level at which trees starve? Increasing shade reduced growth, but surprisingly did not reduce NSC levels, except in a portion of deep shade seedlings that experienced dieback. Once in darkness, leaves died first, with final NSC levels ranging from ~4% (Medium shade, 28 degrees) to 7.5% (Light shade). Stem death generally occurred gradually down the stem. Stem tissues retained ~1-2% NSC when dead. Recovery was still possible when only the upper half of the stem had died; at this point, seedlings had relatively high root NSC levels in their remaining roots (7-10%), with 1-3% starch. No trees recovered after the whole stem had died, at which point, some trees root systems were completely dead. However, most retained substantial amounts of live roots, averaging 5-6% NSC, with 0.25-1.5% starch. Despite the initially similar NSC concentrations, light shade seedlings took longer to reach half stem and whole stem death than seedlings from medium and dark shade. Longer survival times were associated with

  17. The LEU target development and conversion program for the MAPLE reactors and new processing facility

    International Nuclear Information System (INIS)

    Malkoske, G.R.

    2002-01-01

    Historically, the production of molybdenum-99 in the NRU research reactors at Chalk River, Canada has been extracted from reactor targets employing highly enriched uranium (HEU). A reliable supply of HEU metal from the United States used in the manufacture of targets for the NRU research reactor has been a key factor to enable MDS Nordion to develop a secure supply of medical isotopes for the international nuclear medicine community. The molybdenum extraction process from HEU targets provides predictable, consistent yields for our high-volume molybdenum production process. Each link of the isotope supply chain, from isotope production to ultimate use by the physician, has been established using this proven and established method of HEU target irradiation and processing to extract molybdenum-99. To ensure a continued reliable and timely supply of medical isotopes, MDS Nordion is completing the construction of two MAPLE reactors and a New Processing Facility. The design of the MAPLE facilities was based on an established process developed by Atomic Energy of Canada Ltd. (AECL) - extraction of isotopes from HEU target material. However, in concert with the global trend to utilize low enriched uranium (LEU) in research reactors, MDS Nordion has launched a three phase LEU Target Development and Conversion Program for the MAPLE facilities. Phase 1, the Initial Feasibility Study, which identified the technical issues to convert the MAPLE reactor targets from HEU to LEU for large scale commercial production was reported on at the RERTR- 2000 conference. The second phase of the LEU Target Development and Conversion Program was developed with extensive consultation and involvement of experts knowledgeable in target development, process system design, enriched uranium conversion chemistry and commercial scale reactor operations and molybdenum production. This paper will provide an overview of the Phase 2 Conversion Development Program, report on progress to date, and further

  18. Water Deficit and Abscisic Acid Cause Differential Inhibition of Shoot versus Root Growth in Soybean Seedlings 1

    Science.gov (United States)

    Creelman, Robert A.; Mason, Hugh S.; Bensen, Robert J.; Boyer, John S.; Mullet, John E.

    1990-01-01

    Roots often continue to elongate while shoot growth is inhibited in plants subjected to low-water potentials. The cause of this differential response to water deficit was investigated. We examined hypocotyl and root growth, polysome status and mRNA populations, and abscisic acid (ABA) content in etiolated soybean (Glycine max [L.] Merr. cv Williams) seedlings whose growth was inhibited by transfer to low-water potential vermiculite or exogenous ABA. Both treatments affected growth and dry weight in a similar fashion. Maximum inhibition of hypocotyl growth occurred when internal ABA levels (modulated by ABA application) reached the endogenous level found in the elongating zone of seedlings grown in water-deficient vermiculite. Conversely, root growth was affected to only a slight extent in low-water potential seedlings and by most ABA treatments (in some, growth was promoted). In every seedling section examined, transfer of seedlings into low-water potential vermiculite caused ABA levels to increase approximately 5- to 10-fold over that found in well-watered seedlings. Changes in soluble sugar content, polysome status, and polysome mRNA translation products seen in low-water potential seedlings did not occur with ABA treatments sufficient to cause significant inhibition of hypocotyl elongation. These data suggest that both variation in endogenous ABA levels, and differing sensitivity to ABA in hypocotyls and roots can modulate root/shoot growth ratios. However, exogenous ABA did not induce changes in sugar accumulation, polysome status, and mRNA populations seen after transfer into low-water potential vermiculite. Images Figure 6 Figure 7 PMID:16667248

  19. Future warmer seas: increased stress and susceptibility to grazing in seedlings of a marine habitat-forming species.

    Science.gov (United States)

    Hernán, Gema; Ortega, María J; Gándara, Alberto M; Castejón, Inés; Terrados, Jorge; Tomas, Fiona

    2017-11-01

    Increases in seawater temperature are expected to have negative consequences for marine organisms. Beyond individual effects, species-specific differences in thermal tolerance are predicted to modify species interactions and increase the strength of top-down effects, particularly in plant-herbivore interactions. Shifts in trophic interactions will be especially important when affecting habitat-forming species such as seagrasses, as the consequences on their abundance will cascade throughout the food web. Seagrasses are a major component of coastal ecosystems offering important ecosystem services, but are threatened by multiple anthropogenic stressors, including warming. The mechanistic understanding of seagrass responses to warming at multiple scales of organization remains largely unexplored, especially in early-life stages such as seedlings. Yet, these early-life stages are critical for seagrass expansion processes and adaptation to climate change. In this study, we determined the effects of a 3 month experimental exposure to present and predicted mean summer SST of the Mediterranean Sea (25°C, 27°C, and 29°C) on the photophysiology, size, and ecology (i.e., plant-herbivore interactions) of seedlings of the seagrass Posidonia oceanica. Warming resulted in increased mortality, leaf necrosis, and respiration as well as lower carbohydrate reserves in the seed, the main storage organ in seedlings. Aboveground biomass and root growth were also limited with warming, which could hamper seedling establishment success. Furthermore, warming increased the susceptibility to consumption by grazers, likely due to lower leaf fiber content and thickness. Our results indicate that warming will negatively affect seagrass seedlings through multiple direct and indirect pathways: increased stress, reduced establishment potential, lower storage of carbohydrate reserves, and increased susceptibly to consumption. This work provides a significant step forward in understanding the

  20. Simulated changes in biogenic VOC emissions and ozone formation from habitat expansion of Acer Rubrum (red maple)

    International Nuclear Information System (INIS)

    Drewniak, Beth A; Snyder, Peter K; Twine, Tracy E; Steiner, Allison L; Wuebbles, Donald J

    2014-01-01

    A new vegetation trend is emerging in northeastern forests of the United States, characterized by an expansion of red maple at the expense of oak. This has changed emissions of biogenic volatile organic compounds (BVOCs), primarily isoprene and monoterpenes. Oaks strongly emit isoprene while red maple emits a negligible amount. This species shift may impact nearby urban centers because the interaction of isoprene with anthropogenic nitrogen oxides can lead to tropospheric ozone formation and monoterpenes can lead to the formation of particulate matter. In this study the Global Biosphere Emissions and Interactions System was used to estimate the spatial changes in BVOC emission fluxes resulting from a shift in forest composition between oak and maple. A 70% reduction in isoprene emissions occurred when oak was replaced with maple. Ozone simulations with a chemical box model at two rural and two urban sites showed modest reductions in ozone concentrations of up to 5–6 ppb resulting from a transition from oak to red maple, thus suggesting that the observed change in forest composition may benefit urban air quality. This study illustrates the importance of monitoring and representing changes in forest composition and the impacts to human health indirectly through changes in BVOCs. (paper)

  1. Organ-specific proteomics of soybean seedlings under flooding and drought stresses.

    Science.gov (United States)

    Wang, Xin; Khodadadi, Ehsaneh; Fakheri, Baratali; Komatsu, Setsuko

    2017-06-06

    Organ-specific analyses enrich the understanding of plant growth and development under abiotic stresses. To elucidate the cellular responses in soybean seedlings exposed to flooding and drought stresses, organ-specific analysis was performed using a gel-free/label-free proteomic technique. Physiological analysis indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were markedly increased in leaf and root of plants treated with 6days of flooding and drought stresses, respectively. Proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominately affected in leaf, hypocotyl, and root in response to flooding and drought. Notably, the tricarboxylic acid cycle was suppressed in leaf and root under both stresses. Moreover, 17 proteins, including beta-glucosidase 31 and beta-amylase 5, were identified in soybean seedlings under both stresses. The protein abundances of beta-glucosidase 31 and beta-amylase 5 were increased in leaf and root under both stresses. Additionally, the gene expression of beta-amylase 5 was upregulated in leaf exposed to the flooding and drought, and the expression level was highly correlated with the protein abundance. These results suggest that beta-amylase 5 may be involved in carbohydrate mobilization to provide energy to the leaf of soybean seedlings exposed to flooding and drought. This study examined the effects of flooding and drought on soybean seedlings in different organs using a gel-free/label-free proteomic approach. Physiological responses indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were increased in leaf and root of soybean seedlings exposed to flooding and drought for 6days. Functional analysis of acquired protein profiles exhibited that proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominated affected in leaf, hypocotyl, and root

  2. Effects of Corn Canopy on Seedling Emergence of Seven Weed Species

    Directory of Open Access Journals (Sweden)

    F Kordbacheh

    2012-02-01

    Full Text Available In this research corn were planted in 3 densities (8, 12, 16 plant/m2 in two planting patterns (single and double-row with seven summer weed species, including redroot pigweed, green foxtail, annual bluegrass, common lambsquarter, jimsonweed, black nightshade and johnsongrass were planted. Temperature, quality and quantity of light reaching to soil surface were measured and the number of emerged seedlings for each weed species was countered in three sampling dates. Temperature fluctuation wasn't affected by density and planting patterns and was reduced with canopy formation. In all weed species 3 seedling emergence patterns were observed. In small seed species, redroot pigweed had one germination flush, so it was not respond to crop canopy. The number of emerged weed seedlings of annual bluegrass, common lambsquarter and green foxtail were significantly higher in bareground than under corn canopy. In double-row planting pattern was higher compared to the single-row and had three germination flushes. The number of emerged seedlings in the species with relatively large seeds had no significant difference between bareground and under corn canopy in jimsonweed and black nightshade. But it increased in johnsongrass under corn canopy compare to the bare ground. In all three species it was higher in double-row compare to single-row pattern. Jimsonweed had three germination flushes but blacknightshade and johnsongrass had 1 germination flush.

  3. Effect on isoflavone of soybean seedlings by 532nm laser irradiation

    Science.gov (United States)

    Tian, J.; Jin, L. H.; Li, J. M.; Shen, B. J.; Wang, C. Y.; Lu, X.; Zhao, X. L.

    2010-02-01

    We took soybeans as experimental substance to study how the 532nm laser with different power density and irradiation time affected the pullulation ratio of the soybeans, average height of seedlings and the isoflavone content of seedlings' cotyledon and laminae. The mechanism that laser pretreatment of soybean seeds could increase the isoflavone content of the seedlings was discussed in such both aspects as the efficiency of the photosynthesis and the activity of a phenylalanine ammonia-lyase (PAL) as an initial enzyme for synthesizing the isoflavone. The results showed that after the soybean seeds were pretreated by laser, the activity of the PAL and the resultants of the photosynthesis such as the sugar of dissolubility, the sucrose, and the amylum all increased with the soybean seeds irradiated by laser in which the effect on the soybean seeds pretreated by 15mW/mm2 laser for 5 min was the most obvious. As a result, the photosynthesis efficiency of the soybean seedlings increased after being pretreated by laser, which might offer the foundation for accumulating a large amount of isoflavone.

  4. Managing for delicious ecosystem service under climate change: can United States sugar maple (Acer saccharum) syrup production be maintained in a warming climate?

    Science.gov (United States)

    Stephen N. Matthews; Louis R. Iverson

    2017-01-01

    Sugar maple (Acer saccharum) is a highly valued tree in United States (US) and Canada, and its sap when collected from taps and concentrated, makes a delicious syrup. Understanding how this resource may be impacted by climate change and other threats is essential to continue management for maple syrup into the future. Here, we evaluate the current...

  5. Comparison of the enhancement of plasma glucose levels in type 2 diabetes Otsuka Long-Evans Tokushima Fatty rats by oral administration of sucrose or maple syrup.

    Science.gov (United States)

    Nagai, Noriaki; Ito, Yoshimasa; Taga, Atsushi

    2013-01-01

    Maple syrup is used as a premium natural sweeter, and is known for being good for human health. In the present study, we investigate whether maple syrup is suitable as a sweetener in the management of type 2 diabetes using Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type 2 diabetes mellitus. OLETF rats develop type 2 diabetes mellitus by 30 weeks of age, and 60-week-old OLETF rats show hyperglycemia and hypoinsulinemia via pancreatic β-cell dysfunction. The administration of sucrose or maple syrup following an OGT test increased plasma glucose (PG) levels in OLETF rats, but the enhancement in PG following the oral administration of maple syrup was lower than in the case of sucrose administration in both 30- and 60-week-old OLETF rats. Although, the insulin levels in 30-week-old OLETF rats also increased following the oral administration of sucrose or maple syrup, no increase in insulin levels was seen in 60-week-old OLETF rats following the oral administration of either sucrose or maple syrup. No significant differences were observed in insulin levels between sucrose- and maple syrup-administered OLETF rats at either 30 or 60 weeks of age. The present study strongly suggests that the maple syrup may have a lower glycemic index than sucrose, which may help in the prevention of type 2 diabetes.

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

    Science.gov (United States)

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

    2017-01-01

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

  7. Negative and positive interactions among plants: effects of competitors and litter on seedling emergence and growth of forest and grassland species.

    Science.gov (United States)

    Loydi, A; Donath, T W; Otte, A; Eckstein, R L

    2015-05-01

    Living plant neighbours, but also their dead aboveground remains (i.e. litter), may individually exert negative or positive effects on plant recruitment. Although living plants and litter co-occur in most ecosystems, few studies have addressed their combined effects, and conclusions are ambivalent. Therefore, we examined the response in terms of seedling emergence and growth of herbaceous grassland and forest species to different litter types and amounts and the presence of competitors. We conducted a pot experiment testing the effects of litter type (grass, oak), litter amount (low, medium, high) and interspecific competition (presence or absence of four Festuca arundinacea individuals) on seedling emergence and biomass of four congeneric pairs of hemicryptophytes from two habitat types (woodland, grassland). Interactions between litter and competition were weak. Litter presence increased competitor biomass. It also had positive effects on seedling emergence at low litter amounts and negative effects at high litter amounts, while competition had no effect on seedling emergence. Seedling biomass was negatively affected by the presence of competitors, and this effect was stronger in combination with high amounts of litter. Litter affected seedling emergence while competition determined the biomass of the emerged individuals, both affecting early stages of seedling recruitment. High litter accumulation also reduced seedling biomass, but this effect seemed to be additive to competitor effects. This suggests that live and dead plant mass can affect species recruitment in natural systems, but the mechanisms by which they operate and their timing differ. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. IMPROVED METHODS OF OBTAINING PEPPER SEEDLINGS

    Directory of Open Access Journals (Sweden)

    Florina Uleanu

    2012-12-01

    Full Text Available This paper refers to the effect of different types of pots on the level of growth and development of the pepper seedlings in order to clarify the influences caused by use of different recipes transplanters pots. Different biocomposites from renewable resources biodegradable nutritive support were studied. Seedlings were grown in 4 variants of pots M1 (V1, M2 (V2, M3 (V3 and jiffy- pots (V4. The height of the aerial part varied from 14.5 (V1 to 17.4 cm (V4, whereas the root length varied from 5.4 (V1 to 12.6 cm (V4. The number of leaves ranged from 7 (V2 to 12 (V4. The total volume was lowest for V2 (1.5 cm3 and highest for V4 (2.5 cm3, but the root volume was lowest for V2 (0.5 cm3 and highest for V1 (1 cm3. V2 also resulted in the smallest total seedling mass (1.6 g aerial part mass (1.1 g and root mass (0.5 g. Excepting the root volume V4 had the greatest values for the studied indicators.

  9. [Effect of ectomycorrhizae on the growth of Picea koraiensis seedlings].

    Science.gov (United States)

    Song, Rui-Qing; Wu, Ke

    2005-12-01

    Basidioscarps of Agaricales in different Picea koraiensis forest plantations were collected during August-October, 2000. 36 isolaters of species of Agaricales were obtained by isolating and culturing to the basidioscarps. Through indoor inoculation test on seedlings of Picea koraiensis, 6 ectomycorrhizae fungi cultures were obtained from 36 isolaters. The inoculation results show that the period for ectomycorrhizae inoculation to 1-year seedlings of Picea koraiensis should be about 30 days after seedlings emerging, the suitable temperature for ectomycorrhizae forming is about 20 degrees C. 6 ectomycorrhizae strains all have growth-promoting effect to the seedlings of Picea koraiensis. The contents of chlorophyll a of the seedlings inoculated strains of Agaricus silvaticus, 031 and L15 were significantly higher than other strains and control. The contents of chlorophyll b in the seedlings inoculated strains 009, 004, Agaricus silvaticus and L15 were significantly higher than other strains and control. The weights of seedlings which inoculated strains 009, 025, 031, Agaricus silvaticus and L15 were significantly different to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 19.23% and 23.08% more than control; The heights of the seedlings inoculated 6 strains all have significant difference to control, the weight of seedlings inoculated strains of Agaricus silvaticus and L15 are 17.83% and 16.37% more than control. The results of outdoor inoculation show that the seedlings inoculated Agaricus silvaticus grow best on height, 9.25% more than control after inoculated 70 days; the seedlings inoculated strain L15 grow best on collar diameter, 9.92% more than control after inoculated 70 days; the lateral root numbers of seedlings inoculated strain 009 is largest, 51.91% more than control after inoculated 70 days; the main roots of seedlings inoculated strain 009 are longest, 3.36% more than control after inoculated 70 days; the

  10. Recognizing and managing sapstreak disease of sugar maple

    Science.gov (United States)

    David R. Houston; David R. Houston

    1993-01-01

    Sapstreak disease, a potentially serious problem of sugarbushes and forest stands, occurs when the causal fungus, Ceratocystis virescens, invades the sapwood of roots and bases of stems through wounds inflicted during logging, saphauling, or other activities. Describes how to recognize the disease, the factors that affect its occurrence and development, and management...

  11. Effect of ethephon on hardening of Pachystroma longifolium seedlings

    Directory of Open Access Journals (Sweden)

    João Alexandre Lopes Dranski

    2013-06-01

    Full Text Available Immediately after planting, tree seedlings face adverse environmental and biotic stresses that must be overcome to ensure survival and to yield a desirable growth. Hardening practices in the nursery may help improve seedling stress resistance through reduction of aboveground plant tissues and increased root volume and biomass. We conducted an assay to quantify changes in the morphogenesis following application of ethephon on seedlings of Pachystroma longifolium (Ness I. M. Johnst.during hardening. The results showed no effect of the ethephon treatments on the number of leaves but a reduction of up to 50% in seedling height increment, and an increase in stem diameter increment of up to 44% with the 600 mg L-1 ethephon treatment, which consequently altered seedling Dickson Quality Index. Our results indicate that ethephon may help to promote desired morphological changes that occur during seedling hardening in nurseries.

  12. Effect of gamma radiation on seed germination and seedling vigour in cowpea [Vigna unguiculata (L.) Walp.

    International Nuclear Information System (INIS)

    Thimmaiah, S.K.; Mahadevu, P; Srinivasappa, K.N.; Shankara, A.N.

    1998-01-01

    Cowpea [Vigna unguiculata (L.) Walp.) is regarded as hardy and one of the important tropical legumes. The plants respond differently to mutagenic treatments. Ionizing radiations affect a wide range of physiological and biochemical activities of plants. The purpose of this paper is to report the effect of gamma radiation on seed germination and seedling vigour of two important cowpea varieties viz., KBC-1 and TVX-994-02E in M 1 generation under laboratory conditions. (author)

  13. Frost heaving of planted tree seedlings in the boreal forest of northern Sweden

    International Nuclear Information System (INIS)

    Goulet, France

    2000-01-01

    Frost heaving can be a leading cause of tree seedling mortality in many places in the boreal forest of Northern Sweden. The aim of this investigation was to improve our understanding of frost heaving of planted tree seedlings as related to snow cover, scarification, planting methods and soil types. The thesis is based on a review paper, three field experiments and one laboratory experiment. The experiments focus on different methods to control frost heaving of forest tree seedlings and on a number of factors affecting the extent of frost heaving. The review paper identifies the many aspects of frost heaving of forest tree seedlings and agricultural crops based on an intensive review of the research contributions made during the last century. Even if many investigations have been carried out with the aim to decrease the extent of frost heaving, very little quantitative results are available for tree seedlings. In a field experiment, the choice of planting positions was effective in decreasing frost heaving of planted seedlings following mounding or disc-trenching. Seedlings planted in the depressions were largely affected by frost heaving with a maximal vertical displacement of 5.4 cm while frost heaving did not occur on the top of the mound. On the other hand, the planting time and planting depth had no influence on the extent of frost heaving. In another field experiment the size of the scarified patches was strongly correlated to frost heaving which reached between 7.6 and 11.5 cm in 4 and 8-dm patches compared to between 4.4 and 5.3 in non-scarified soil and in a 1-dm patch. Ground vegetation probably decreases the diurnal temperature variation and the number of freezing-thawing cycles. The duration and magnitude of frost temperatures, the frost hour sum, increased with patch size. The difference between the 8-dm and 1-dm patch increased to 2064 hour-degrees at the end of the winter. In larger patches, the planting depth seemed to be effective in reducing the

  14. Frost heaving of planted tree seedlings in the boreal forest of northern Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Goulet, France

    2000-07-01

    Frost heaving can be a leading cause of tree seedling mortality in many places in the boreal forest of Northern Sweden. The aim of this investigation was to improve our understanding of frost heaving of planted tree seedlings as related to snow cover, scarification, planting methods and soil types. The thesis is based on a review paper, three field experiments and one laboratory experiment. The experiments focus on different methods to control frost heaving of forest tree seedlings and on a number of factors affecting the extent of frost heaving. The review paper identifies the many aspects of frost heaving of forest tree seedlings and agricultural crops based on an intensive review of the research contributions made during the last century. Even if many investigations have been carried out with the aim to decrease the extent of frost heaving, very little quantitative results are available for tree seedlings. In a field experiment, the choice of planting positions was effective in decreasing frost heaving of planted seedlings following mounding or disc-trenching. Seedlings planted in the depressions were largely affected by frost heaving with a maximal vertical displacement of 5.4 cm while frost heaving did not occur on the top of the mound. On the other hand, the planting time and planting depth had no influence on the extent of frost heaving. In another field experiment the size of the scarified patches was strongly correlated to frost heaving which reached between 7.6 and 11.5 cm in 4 and 8-dm patches compared to between 4.4 and 5.3 in non-scarified soil and in a 1-dm patch. Ground vegetation probably decreases the diurnal temperature variation and the number of freezing-thawing cycles. The duration and magnitude of frost temperatures, the frost hour sum, increased with patch size. The difference between the 8-dm and 1-dm patch increased to 2064 hour-degrees at the end of the winter. In larger patches, the planting depth seemed to be effective in reducing the

  15. Biodegradable bags for the production of plant seedlings

    OpenAIRE

    Bilck,Ana Paula; Olivato,Juliana Bonametti; Yamashita,Fabio; Souza,José Roberto Pinto de

    2014-01-01

    The production of plant seedlings has traditionally used polyethylene bags, which are thrown out in the soil or burned after transplant because the large amount of organic material attached to the bags makes recycling difficult. Additionally, when a seedling is taken from the bag for transplant, there is the risk of root damage, which compromises the plant’s development. In this study, we developed biodegradable bags to be used in seedling production, and we verify their influence on the deve...

  16. Longleaf pine bud development: influence of seedling nutrition

    Science.gov (United States)

    J. P. Barnett; D. P. Jackson; R. K. Dumroese

    2010-01-01

    A subset of seedlings from a larger study (Jackson and others 2006, 2007) were selected and evaluated for two growing seasons to relate bud development, and root-collar diameter (RCD), and height growth with three nursery fertilization rates. We chose seedlings in the 0.5 (lowest), 2.0 (mid-range), and 4.0 (highest) mg of nitrogen per seedling treatments. Buds moved...

  17. AVOCADO SEEDLINGS MULTIPLE STEMS PRODUCTION

    Directory of Open Access Journals (Sweden)

    MARCUS VINICIUS SANDOVAL PAIXÃO

    2016-01-01

    Full Text Available ABSTRACT This study aimed to evaluate the potential of multi-stems in avocado seeds according to their mass as well as the adventitious rooting of multi-stem budding with or without the use of auxin. The research was carried out at the Vegetation House of Federal Institute of Espírito Santo, Campus Santa Teresa -ES, with seeds of different masses: 100 g, in which each experimental unit was made of five seeds, distributed within five repetitions, under a completely randomized design. The seeds were put to germinate and the percentage number of emergence and multiple stems were evaluated. After 150 days, the following evaluations were carried out: survival of rooted cuttings; number of leaves; stem diameter; root length; root volume; root and shoot fresh mass; root and shoot dry mass; shoot height; absolute growth and shoot growth rate; shoot dry weight/root dry mass ratio; shoot height/stem diameter ratio; shoot height/root length and Dickson's quality index ratio. Avocado seeds with mass over 100 g and between 81-100 g presented higher percentage of multiple stems. Rods over 20 cm that were not treated with IBA (indole-3-butyric acid resulted on avocado plants of better quality. The use of IBA (2000 mg L-1 does not affect the rooting and growth of avocado's multi-stem plants.

  18. Analysis of plastic residues in maple sap and syrup collected from tubing systems sanitized with isopropyl alcohol

    Directory of Open Access Journals (Sweden)

    Luc Lagacé

    2017-05-01

    Full Text Available A plastic tubing system operated under vacuum is usually used to collect sap from maple trees during spring time to produce maple syrup. This system is commonly sanitized with isopropyl alcohol (IPA to remove microbial contamination colonizing the system during the sugar season. Questions have been raised whether IPA would contribute to the leaching of plastic residues in maple sap and syrup coming from sanitized systems. First, an extraction experiment was performed in the lab on commercial plastic tubing materials that were submitted to IPA under harsh conditions. The results of the GC-MS analysis revealed the presence of many compounds that served has target for further tests. Secondly, tests were done on early and mid-season maple sap and syrup coming from many sugarbushes using IPA or not to determine potential concentrations of plastic residues. Results obtained from sap and syrup samples showed that no quantifiable (< 1–75 μg/L concentration of any plastic molecules tested was determined in all samples coming from IPA treated or not treated systems. However, some samples of first sap run used as a rinse solution to be discarded before the season start and that were coming from non sanitized or IPA sanitized systems, showed quantifiable concentrations of chemical residue such as ultraviolet protector (octabenzone. These results show that IPA can be safely used to sanitize maple sap collection system in regards to the leaching of plastic residues in maple sap and syrup and reinforced the need to thoroughly rinse the tubing system at the beginning of the season for both sanitized and non sanitized systems. Keywords: Food science, Food safety, Materials chemistry

  19. Further investigation into maple syrup yields 3 new lignans, a new phenylpropanoid, and 26 other phytochemicals.

    Science.gov (United States)

    Li, Liya; Seeram, Navindra P

    2011-07-27

    Maple syrup is made by boiling the sap collected from certain maple ( Acer ) species. During this process, phytochemicals naturally present in tree sap are concentrated in maple syrup. Twenty-three phytochemicals from a butanol extract of Canadian maple syrup (MS-BuOH) had previously been reported; this paper reports the isolation and identification of 30 additional compounds (1-30) from its ethyl acetate extract (MS-EtOAc) not previously reported from MS-BuOH. Of these, 4 compounds are new (1-3, 18) and 20 compounds (4-7, 10-12, 14-17, 19, 20, 22-24, 26, and 28-30) are being reported from maple syrup for the first time. The new compounds include 3 lignans and 1 phenylpropanoid: 5-(3″,4″-dimethoxyphenyl)-3-hydroxy-3-(4'-hydroxy-3'-methoxybenzyl)-4-(hydroxymethyl)dihydrofuran-2-one (1), (erythro,erythro)-1-[4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3,5-dimethoxyphenyl]-1,2,3-propanetriol (2), (erythro,threo)-1-[4-[2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3,5-dimethoxyphenyl]-1,2,3-propanetriol (3), and 2,3-dihydroxy-1-(3,4- dihydroxyphenyl)-1-propanone (18), respectively. In addition, 25 other phenolic compounds were isolated including (threo,erythro)-1-[4-[(2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3-methoxyphenyl]-1,2,3-propanetriol (4), (threo,threo)-1-[4-[(2-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-1-(hydroxymethyl)ethoxy]-3-methoxyphenyl]-1,2,3-propanetriol (5), threo-guaiacylglycerol-β-O-4'-dihydroconiferyl alcohol (6), erythro-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2,6-dimethoxyphenoxy]-1,3-propanediol (7), 2-[4-[2,3-dihydro-3-(hydroxymethyl)-5-(3-hydroxypropyl)-7-methoxy-2-benzofuranyl]-2,6-dimethoxyphenoxy]-1-(4-hydroxy-3-methoxyphenyl)-1,3-propanediol (8), acernikol (9), leptolepisol D (10), buddlenol E (11), (1S,2R)-2-[2,6-dimethoxy-4-[(1S,3aR,4S,6aR)-tetrahydro-4-(4-hydroxy-3,5-dimethoxyphenyl)-1H,3H-furo[3,4-c]furan-1-yl]phenoxy]-1-(4-hydroxy-3-methoxyphenyl)-1

  20. Long branch-chains of amylopectin with B-type crystallinity in rice seed with inhibition of starch branching enzyme I and IIb resist in situ degradation and inhibit plant growth during seedling development : Degradation of rice starch with inhibition of SBEI/IIb during seedling development.

    Science.gov (United States)

    Pan, Ting; Lin, Lingshang; Wang, Juan; Liu, Qiaoquan; Wei, Cunxu

    2018-01-08

    Endosperm starch provides prime energy for cereal seedling growth. Cereal endosperm with repression of starch branching enzyme (SBE) has been widely studied for its high resistant starch content and health benefit. However, in barley and maize, the repression of SBE changes starch component and amylopectin structure which affects grain germination and seedling establishment. A high resistant starch rice line (TRS) has been developed through inhibiting SBEI/IIb, and its starch has very high resistance to in vitro hydrolysis and digestion. However, it is unclear whether the starch resists in situ degradation in seed and influences seedling growth after grain germination. In this study, TRS and its wild-type rice cultivar Te-qing (TQ) were used to investigate the seedling growth, starch property changes, and in situ starch degradation during seedling growth. The slow degradation of starch in TRS seed restrained the seedling growth. The starch components including amylose and amylopectin were simultaneously degraded in TQ seeds during seedling growth, but in TRS seeds, the amylose was degraded faster than amylopectin and the amylopectin long branch-chains with B-type crystallinity had high resistance to in situ degradation. TQ starch was gradually degraded from the proximal to distal region of embryo and from the outer to inner in endosperm. However, TRS endosperm contained polygonal, aggregate, elongated and hollow starch from inner to outer. The polygonal starch similar to TQ starch was completely degraded, and the other starches with long branch-chains of amylopectin and B-type crystallinity were degraded faster at the early stage of seedling growth but had high resistance to in situ degradation during TRS seedling growth. The B-type crystallinity and long branch-chains of amylopectin in TRS seed had high resistance to in situ degradation, which inhibited TRS seedling growth.

  1. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O. [Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxide Materials and Nanomaterials, Politehnica University of Bucharest, Polizu Street No. 1–7, 011061 Bucharest (Romania); Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Mihaiescu, D. [Faculty of Applied Chemistry and Materials Science, Department of Organic Chemistry, Politehnica University of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Enculescu, M. [National Institute of Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chifiriuc, M.C. [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest—ICUB, Research Institute of the University of Bucharest, 77206 Bucharest (Romania); Boehm, R.D.; Narayan, R.J. [Biomedical Engineering, University of North Carolina, Chapel Hill, NC (United States); Chrisey, D.B. [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA (United States)

    2015-05-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  2. MAPLE deposition of polypyrrole-based composite layers for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Paun, Irina Alexandra, E-mail: irina.paun@physics.pub.ro [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Acasandrei, Adriana Maria [Horia Hulubei National Institute for Physics and Nuclear Engineering IFIN-HH, Magurele, Bucharest RO-077125 (Romania); Luculescu, Catalin Romeo, E-mail: catalin.luculescu@inflpr.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Mustaciosu, Cosmin Catalin [Horia Hulubei National Institute for Physics and Nuclear Engineering IFIN-HH, Magurele, Bucharest RO-077125 (Romania); Ion, Valentin [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Mihailescu, Mona; Vasile, Eugenia [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); Dinescu, Maria, E-mail: dinescum@nipne.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania)

    2015-12-01

    Highlights: • PPy-based composite layers for bone regeneration were produced by MAPLE. • Conductive PPy nanograins were embedded in insulating PLGA and PU matrices. • PLGA was chosen for providing biodegradability and PU for toughness and elasticity. • The layers conductivities reached 10{sup −2} S/cm for PPy loadings of 1:10 weight ratios. • The layers promoted osteoblast viability, proliferation and mineralization. - Abstract: We report on biocompatible, electrically conductive layers of polypyrrole (PPy)-based composites obtained by Matrix Assisted Pulsed Laser Evaporation (MAPLE) for envisioned bone regeneration. In order to preserve the conductivity of the PPy while overcoming its lack of biodegradability and low mechanical resilience, conductive PPy nanograins were embedded in two biocompatible, insulating polymeric matrices, i.e. poly(lactic-co-glycolic)acid (PLGA) and polyurethane (PU). PLGA offers the advantage of full biodegradability into non-toxic products, while PU provides toughness and elasticity. The PPy nanograins formed micro-domains and networks within the PLGA and PU matrices, in a compact spatial arrangement favorable for electrical percolation. The proposed approach allowed us to obtain PPy-based composite layers with biologically meaningful conductivities up to 10{sup −2} S/cm for PPy loadings as low as 1:10 weight ratios. Fluorescent staining and viability assays showed that the MG63 osteoblast-like cells cultured on the PPy-based layers deposited by MAPLE were viable and retained their capacity to proliferate. The performance of the proposed method was demonstrated by quantitative evaluation of the calcium phosphate deposits from the cultured cells, as indicative for cell mineralization. Electrical stimulation using 200 μA currents passing through the PPy-based layers, during a time interval of 4 h, enhanced the osteogenesis in the cultured cells. Despite their lowest conductivity, the PPy/PU layers showed the best

  3. Fungi in Ontario maple syrup & some factors that determine the presence of mold damage.

    Science.gov (United States)

    Frasz, Samantha L; Miller, J David

    2015-08-17

    Maple syrup is a high value artisanal product produced mainly in Canada and a number of States primarily in the northeast USA. Mold growth (Wallemia sebi) on commercial product was first reported in syrup in 1908. Since then, few data have been published. We conducted a systematic examination for fungi in maple syrup from 68 producers from all of the syrup-producing areas of Ontario, Canada. The mean pH of the samples was pH 6.82, sugar content averaged 68.0±0.89 °Brix and aw averaged 0.841±0.011. Some 23 species of fungi were isolated based on morphology and molecular techniques. The most common fungus in the maple syrup samples was Eurotium herbariorum, followed by Penicillium chrysogenum, Aspergillus penicillioides, Aspergillus restrictus, Aspergillus versicolor and two species of Wallemia. Cladosporium cladosporioides was also common but only recovered when fungi known from high sugar substrates were also present in the mold damaged sample. The rarely reported yeast Citeromyces matrinsis was found in samples from three producers. There appear to be three potential causes for mold damage observed. High aw was associated with about one third of the mold damage. Independently, cold packing (bottling at ~25 °C) was a risk factor. However, syrup of good quality and quite low aw values was contaminated. We hypothesize that sanitation in the bottling line and other aspects of the bottling process may be partial explanations. Clarifying this requires further study. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Flexible heterostructures based on metal phthalocyanines thin films obtained by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Socol, M., E-mail: cela@infim.ro [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Preda, N.; Rasoga, O. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Breazu, C. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); University of Bucharest, Faculty of Physics, 405 Atomistilor Street, PO Box MG-11, 077125 Bucharest-Magurele (Romania); Stavarache, I. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Stanculescu, F. [University of Bucharest, Faculty of Physics, 405 Atomistilor Street, PO Box MG-11, 077125 Bucharest-Magurele (Romania); Socol, G.; Gherendi, F.; Grumezescu, V.; Popescu-Pelin, G. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-36, 077125 Bucharest-Magurele (Romania); Girtan, M. [Laboratoire de Photonique d’Angers, Université d’Angers, 2, Bd. Lavoisier, 49045 Angers (France); Stefan, N. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-36, 077125 Bucharest-Magurele (Romania)

    2016-06-30

    Highlights: • Organic heterostructures prepared by MAPLE having a large absorbtion domain. • Photogeneration process is evidenced in the structure with ZnPc:TPyP mixed layer. • An increase in current value is observed in the structure with MgPc:TPyP mixed layer. - Abstract: Heterostructures based on zinc phthalocyanine (ZnPc), magnesium phthalocyanine (MgPc) and 5,10,15,20-tetra(4-pyrydil)21H,23H-porphine (TPyP) were deposited on ITO flexible substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. Organic heterostructures containing (TPyP/ZnPc(MgPc)) stacked or (ZnPc(MgPc):TPyP) mixed layers were characterized by X-ray diffraction-XRD, photoluminescence-PL, UV–vis and FTIR spectroscopy. No chemical decomposition of the initial materials was observed. The investigated structures present a large spectral absorption in the visible range making them suitable for organic photovoltaics applications (OPV). Scanning electron microscopy-SEM and atomic force microscopy-AFM revealed morphologies typical for the films prepared by MAPLE. The current–voltage characteristics of the investigated structures, measured in dark and under light, present an improvement in the current value (∼3 order of magnitude larger) for the structure based on the mixed layer (Al/MgPc:TPyP/ITO) in comparison with the stacked layer (Al/MgPc//TPyP/ITO). A photogeneration process was evidenced in the case of structures Al/ZnPc:TPyP/ITO with mixed layers.

  5. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    International Nuclear Information System (INIS)

    Cristescu, R.; Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O.; Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N.; Mihaiescu, D.; Enculescu, M.; Chifiriuc, M.C.; Boehm, R.D.; Narayan, R.J.; Chrisey, D.B.

    2015-01-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  6. Flexible heterostructures based on metal phthalocyanines thin films obtained by MAPLE

    International Nuclear Information System (INIS)

    Socol, M.; Preda, N.; Rasoga, O.; Breazu, C.; Stavarache, I.; Stanculescu, F.; Socol, G.; Gherendi, F.; Grumezescu, V.; Popescu-Pelin, G.; Girtan, M.; Stefan, N.

    2016-01-01

    Highlights: • Organic heterostructures prepared by MAPLE having a large absorbtion domain. • Photogeneration process is evidenced in the structure with ZnPc:TPyP mixed layer. • An increase in current value is observed in the structure with MgPc:TPyP mixed layer. - Abstract: Heterostructures based on zinc phthalocyanine (ZnPc), magnesium phthalocyanine (MgPc) and 5,10,15,20-tetra(4-pyrydil)21H,23H-porphine (TPyP) were deposited on ITO flexible substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. Organic heterostructures containing (TPyP/ZnPc(MgPc)) stacked or (ZnPc(MgPc):TPyP) mixed layers were characterized by X-ray diffraction-XRD, photoluminescence-PL, UV–vis and FTIR spectroscopy. No chemical decomposition of the initial materials was observed. The investigated structures present a large spectral absorption in the visible range making them suitable for organic photovoltaics applications (OPV). Scanning electron microscopy-SEM and atomic force microscopy-AFM revealed morphologies typical for the films prepared by MAPLE. The current–voltage characteristics of the investigated structures, measured in dark and under light, present an improvement in the current value (∼3 order of magnitude larger) for the structure based on the mixed layer (Al/MgPc:TPyP/ITO) in comparison with the stacked layer (Al/MgPc//TPyP/ITO). A photogeneration process was evidenced in the case of structures Al/ZnPc:TPyP/ITO with mixed layers.

  7. PENGEMBANGAN MODEL PEMBELAJARAN KALKULUS BERBANTUAN KOMPUTER MELALUI PROGRAM MAPLE DI PROGRAM STUDI PENDIDIKAN MATEMATIKA

    Directory of Open Access Journals (Sweden)

    Parma Parma

    2015-03-01

    Full Text Available The purpose of this research is the renewal of learning methods into calculus courses with modules of computer-assisted learning through maple. The products produced in this study is in the form of teaching materials in the form of calculus course lab guide through maple. With the resulting product of this research will be useful theoretically and practically. Theoretically, it is expected to result in the learning principles that can improve the quality of learning calculus, so as to enrich the theory of the existing learning models.Type of research is the development, which is planned for 2 (two years of activity. The design of the study in the first year needs assessment was conducted to obtain data on the characteristics and the need for calculus learning model that has been done in mathematics education courses Se-Lombok Island. The instruments used are interviews and questionnaires were imposed on the calculus course lecturers, heads of university and college students. The collected data was then analyzed using descriptive analysis techniques.The study design in the second year is the development of research that aims to develop software products in the form of learning calculus with computer-aided learning model through the maple. Learning products developed include: (1. Models and learning strategies; (2. The device in the form of learning, Syllabus, Unit Learning Event, Book Teaching Material Calculus computer-assisted, student worksheet; and (3 test the learning outcomes. Product trials involving calculus course lecturers, heads of university and student mathematics education courses Se-Lombok. The test results were analyzed using descriptive statistics   

  8. Deposition of matrix-free fullerene films with improved morphology by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2013-01-01

    Thin films of C60 were deposited by matrix-assisted pulsed laser evaporation (MAPLE) from a frozen target of anisole with 0.67 wt% C60. Above a fluence of 1.5 J/cm2 the C60 films are strongly non-uniform and are resulting from transfer of matrix-droplets containing fullerenes. At low fluence...... the fullerene molecules in the films are intact, the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the film. This may indicate a regime of dominant evaporation at low fluence which merges into the MAPLE regime of liquid ejection of the host matrix...

  9. Selecting a MAPLE research reactor core for 1-10 mW operation

    International Nuclear Information System (INIS)

    Smith, H.J.; Roy, M.-F.; Carlson, P.A.

    1986-06-01

    The MAPLE class of research reactors is designed so that a single reactor concept can satisfy a wide range of practical applications. This paper reports the results of physics studies performed on a number of potential core configurations fuelled with either 5 w/o or 8 w/o enriched UO 2 or 20 w/o U 3 Si-Al and assesses the relative merits of each. Recommended core designs are given to maximize the neutron fluxes available for scientific application and isotope production

  10. Management of a Woman With Maple Syrup Urine Disease During Pregnancy, Delivery, and Lactation.

    Science.gov (United States)

    Wessel, Ann E; Mogensen, Kris M; Rohr, Frances; Erick, Miriam; Neilan, Edward G; Chopra, Sameer; Levy, Harvey L; Gray, Kathryn J; Wilkins-Haug, Louise; Berry, Gerard T

    2015-09-01

    Maple syrup urine disease (MSUD) is an inherited disorder of metabolism of the branched-chain amino acids leucine, isoleucine, and valine. Complications of acute elevation in plasma leucine include ketoacidosis and risk of cerebral edema, which can be fatal. Individuals with MSUD are at risk of metabolic crisis throughout life, especially at times of physiological stress. We present a case of successful management of a woman with MSUD through pregnancy, delivery, postpartum, and lactation, including nutrition therapy using modified parenteral nutrition. © 2014 American Society for Parenteral and Enteral Nutrition.

  11. Proposed Robot Scheme with 5 DoF and Dynamic Modelling Using Maple Software

    Directory of Open Access Journals (Sweden)

    Shala Ahmet

    2017-11-01

    Full Text Available In this paper is represented Dynamical Modelling of robots which is commonly first important step of Modelling, Analysis and Control of robotic systems. This paper is focused on using Denavit-Hartenberg (DH convention for kinematics and Newton-Euler Formulations for dynamic modelling of 5 DoF - Degree of Freedom of 3D robot. The process of deriving of dynamical model is done using Software Maple. Derived Dynamical Model of 5 DoF robot is converted for Matlab use for future analysis, control and simulations.

  12. Molecular interaction between Methylobacterium extorquens and seedlings: growth promotion, methanol consumption, and localization of the methanol emission site.

    Science.gov (United States)

    Abanda-Nkpwatt, Daniel; Müsch, Martina; Tschiersch, Jochen; Boettner, Mewes; Schwab, Wilfried

    2006-01-01

    Four Methylobacterium extorquens strains were isolated from strawberry (Fragaria x ananassa cv. Elsanta) leaves, and one strain, called ME4, was tested for its ability to promote the growth of various plant seedlings. Seedling weight and shoot length of Nicotiana tabacum, Lycopersicon esculentum, Sinapis alba, and Fragaria vesca increased significantly in the presence of the pink-pigmented facultative methylotroph (PPFM), but the germination behaviour of seeds from six other plants was not affected. The cell-free supernatant of the bacterial culture stimulated germination, suggesting the production of a growth-promoting agent by the methylotroph. Methanol emitted from N. tabacum seedlings, as determined by proton-transfer-reaction mass spectrometry (PTR-MS), ranged from 0.4 to 0.7 ppbv (parts per billion by volume), while significantly lower levels (0.005 to 0.01 ppbv) of the volatile alcohol were measured when the seedlings were co-cultivated with M. extorquens ME4, demonstrating the consumption of the gaseous methanol by the bacteria. Additionally, by using cells of the methylotrophic yeast Pichia pastoris transformed with the pPICHS/GFP vector harbouring a methanol-sensitive promoter in combination with the green fluorescence protein (GFP) reporter gene, stomata were identified as the main source of the methanol emission on tobacco cotyledons. Methylobacterium extorquens strains can nourish themselves using the methanol released by the stomata and release an agent promoting the growth of the seedlings of some crop plants.

  13. The value of trophic interactions for ecosystem function: dung beetle communities influence seed burial and seedling recruitment in tropical forests.

    Science.gov (United States)

    Griffiths, Hannah M; Bardgett, Richard D; Louzada, Julio; Barlow, Jos

    2016-12-14

    Anthropogenic activities are causing species extinctions, raising concerns about the consequences of changing biological communities for ecosystem functioning. To address this, we investigated how dung beetle communities influence seed burial and seedling recruitment in the Brazilian Amazon. First, we conducted a burial and retrieval experiment using seed mimics. We found that dung beetle biomass had a stronger positive effect on the burial of large than small beads, suggesting that anthropogenic reductions in large-bodied beetles will have the greatest effect on the secondary dispersal of large-seeded plant species. Second, we established mesocosm experiments in which dung beetle communities buried Myrciaria dubia seeds to examine plant emergence and survival. Contrary to expectations, we found that beetle diversity and biomass negatively influenced seedling emergence, but positively affected the survival of seedlings that emerged. Finally, we conducted germination trials to establish the optimum burial depth of experimental seeds, revealing a negative relationship between burial depth and seedling emergence success. Our results provide novel evidence that seed burial by dung beetles may be detrimental for the emergence of some seed species. However, we also detected positive impacts of beetle activity on seedling recruitment, which are probably because of their influence on soil properties. Overall, this study provides new evidence that anthropogenic impacts on dung beetle communities could influence the structure of tropical forests; in particular, their capacity to regenerate and continue to provide valuable functions and services. © 2016 The Author(s).

  14. Effects Of Irrigation With Saline Water, And Soil Type On Germination And Seedling Growth Of Sweet Maize (Zea Mays L.)

    International Nuclear Information System (INIS)

    Mostafa, A.Z.; Amato, M.; Hamdi, A.; Mostafa, A.Z.; Galal, Y.G.M.; Lotfy, S.M.

    2012-01-01

    Germination and early growth of maize Sweet Maize (Zea mays L.), var. (SEL. CONETA) under irrigation with saline water were investigated in a pot experiment with different soil types. Seven salinity levels of irrigation water up to 12 dS/m were used on a Clay soil (C) and a Sandy-Loam (SL). Emergence of maize was delayed under irrigation with saline water, and the final percentage of germination was reduced only at 8 dS/m or above. Seedling shoot and root growth were reduced starting at 4 dS/m of irrigation water. Salts accumulated more in the C soil but reductions in final germination rate and seedling growth were larger in the SL soil, although differences were not always significant. Data indicate that germination is rather tolerant to salinity level in var. SEL. CONETA whereas seedling growth is reduced at moderate salinity levels, and that soil type affects plant performance under irrigation with saline water

  15. Pre-sowing application of ascorbic acid and salicylic acid to seed of pumpkin and seedling response to salt

    International Nuclear Information System (INIS)

    Rafique, N.; Raza, S.H.; Qasim, M.; Iqbal, N.

    2011-01-01

    The effects of seed soaking with salicylic acid or ascorbic acid on pumpkin seedlings growth under saline (10 dS m/sup -1/) conditions were investigated. Seedlings fresh weight, protein contents, protease and nitrate reductase activities were significantly affected by 15 and 30 mg L/sup -1/ salicylic acid and 30 mg L/sup -1/ ascorbic acid priming treatments, under both normal and saline conditions. Priming reduced the severity of the salt stress, the amelioration was better due to 30 mg L/sup -1/ ascorbic acid or 30 mg L/sup -1/ salicylic acid treatments as these treatments showed best results on seedling growth, fresh and dry matter production under non-saline and saline environments. Application of seed priming with ascorbic acid and salicylic acid in pumpkin ameliorate the adverse effects of salt stress. (author)

  16. Effectiveness of thiophanate-methyl, trifloxystrobin and vinclozolin on canker caused by Phoma exigua Desm. on ash tree seedlings

    Directory of Open Access Journals (Sweden)

    Cuvelier M.

    2006-01-01

    Full Text Available In recent years several cases of cankers caused by Phoma exigua on ash tree seedlings have been reported in Belgian nurseries, leading to a total loss of the affected crops. Similar symptoms have been observed on ash tree seedlings elsewhere in Europe, notably in France and in Great Britain, but the pathogenicity was never established. Inoculation and re-isolation tests were therefore undertaken and demonstrated the phytopathogenic character of P. exigua on ash. Moreover the effectiveness of three fungicides (thiophanate-methyl, trifloxystrobin, vinclozolin against stem canker of ash tree seedlings was studied. In vitro tests were conducted to evaluate the ability of these fungicides to inhibit mycelium growth and spore germination. The extent to which they reduced the symptoms was estimated in a field trial. The results of this study allowed to get by the Belgian proper authorities the use extension of thiophanate-methyl for the control of canker caused by P. exigua in forest nurseries.

  17. Planting and care of fine hardwood seedlings: Nursery production of hardwood seedlings

    Science.gov (United States)

    Douglass F. Jacobs

    2003-01-01

    Access to quality tree seedlings is an essential component of a successful hardwood reforestation project. Hardwood plantations may be established by sowing seed directly to a field site, but the success of direct seeding operations has been inconsistent for many species, which indicates that more research is needed before this practice can be recommended. For...

  18. Seed-vectored endophytic bacteria modulate development of rice seedlings.

    Science.gov (United States)

    Verma, S K; Kingsley, K; Irizarry, I; Bergen, M; Kharwar, R N; White, J F

    2017-06-01

    The aim of the present study was to evaluate the effects of the removal of indigenous bacteria from rice seeds on seedling growth and development. Here we report the presence of three indigenous endophytic bacteria in rice seeds that play important roles in modulating seedling development (shoot and root lengths, and formation of root hairs and secondary roots) and defence against pathogens. Seed-associated bacteria were removed using surface sterilization with NaOCl (bleach) followed by antibiotic treatment. When bacteria were absent, growth of seedlings in terms of root hair development and overall seedling size was less than that of seedlings that contained bacteria. Reactive oxygen staining of seedlings showed that endophytic bacteria became intracellular in root parenchyma cells and root hairs. Roots containing endophytic bacteria were seen to stain densely for reactive oxygen, while roots free of bacteria stained lightly for reactive oxygen. Bacteria were isolated and identified as Enterobacter asburiae (VWB1), Pantoea dispersa (VWB2) and Pseudomonas putida (VWB3) by 16S rDNA sequencing. Bacteria were found to produce indole acetic acid (auxins), inhibited the pathogen Fusarium oxysporum and solubilized phosphate. Reinoculation of bacteria onto seedlings derived from surface-disinfected rice and Bermuda grass seeds significantly restored seedling growth and development. Rice seeds harbour indigenous bacterial endophytes that greatly influence seedling growth and development, including root and shoot lengths, root hair formation and disease susceptibility of rice seedlings. This study shows that seeds of rice naturally harbour bacterial endophytes that play key roles in modulation of seedling development. © 2017 The Society for Applied Microbiology.

  19. Interactive effects of juvenile defoliation, light conditions, and interspecific competition on growth and ectomycorrhizal colonization of Fagus sylvatica and Pinus sylvestris seedlings.

    Science.gov (United States)

    Trocha, Lidia K; Weiser, Ewa; Robakowski, Piotr

    2016-01-01

    Seedlings of forest tree species are exposed to a number of abiotic (organ loss or damage, light shortage) and biotic (interspecific competition) stress factors, which may lead to an inhibition of growth and reproduction and, eventually, to plant death. Growth of the host and its mycorrhizal symbiont is often closely linked, and hence, host damage may negatively affect the symbiont. We designed a pot experiment to study the response of light-demanding Pinus sylvestris and shade-tolerant Fagus sylvatica seedlings to a set of abiotic and biotic stresses and subsequent effects on ectomycorrhizal (ECM) root tip colonization, seedling biomass, and leaf nitrogen content. The light regime had a more pronounced effect on ECM colonization than did juvenile damage. The interspecific competition resulted in higher ECM root tip abundance for Pinus, but this effect was insignificant in Fagus. Low light and interspecific competition resulted in lower seedling biomass compared to high light, and the effect of the latter was partially masked by high light. Leaf nitrogen responded differently in Fagus and Pinus when they grew in interspecific competition. Our results indicated that for both light-demanding (Pinus) and shade-tolerant (Fagus) species, the light environment was a major factor affecting seedling growth and ECM root tip abundance. The light conditions favorable for the growth of seedlings may to some extent compensate for the harmful effects of juvenile organ loss or damage and interspecific competition.

  20. Exogenous Spermidine Alleviates Low Temperature Injury in Mung Bean (Vigna radiata L. Seedlings by Modulating Ascorbate-Glutathione and Glyoxalase Pathway

    Directory of Open Access Journals (Sweden)

    Kamrun Nahar

    2015-12-01

    Full Text Available The role of exogenous spermidine (Spd in alleviating low temperature (LT stress in mung bean (Vigna radiata L. cv. BARI Mung-3 seedlings has been investigated. Low temperature stress modulated the non-enzymatic and enzymatic components of ascorbate-glutathione (AsA-GSH cycle, increased H2O2 content and lipid peroxidation, which indicate oxidative damage of seedlings. Low temperature reduced the leaf relative water content (RWC and destroyed leaf chlorophyll, which inhibited seedlings growth. Exogenous pretreatment of Spd in LT-affected seedlings significantly increased the contents of non-enzymatic antioxidants of AsA-GSH cycle, which include AsA and GSH. Exogenous Spd decreased dehydroascorbate (DHA, increased AsA/DHA ratio, decreased glutathione disulfide (GSSG and increased GSH/GSSG ratio under LT stress. Activities of AsA-GSH cycle enzymes such as ascorbate peroxidase (APX, monodehydroascorbate reductase (MDHAR, dehydroascorbate reductase (DHAR and glutathione reductase (GR increased after Spd pretreatment in LT affected seedlings. Thus, the oxidative stress was reduced. Protective effects of Spd are also reflected from reduction of methylglyoxal (MG toxicity by improving glyoxalase cycle components, and by maintaining osmoregulation, water status and improved seedlings growth. The present study reveals the vital roles of AsA-GSH and glyoxalase cycle in alleviating LT injury.