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11.
Henna Pihlajaniemi Mirja Siuruainen Pasi Rautio Kari Laine Sirkka-Liisa Peteri Satu Huttunen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):275-286
Abstract Five old shrub rose taxa were studied in field experiments in northern Finland during the years 1993–1999. The plant material was micro-propagated from woody plants selected for their ornamental value and hardiness for northern areas of Finland. The observations in the experiments were based on phenological monitoring and survey of plant success. The results revealed significant differences in the success of the different rose genotypes, and the most valuable genotypes were identified. Micropropagation was successfully used as a propagation method and these in vitro propagated roses grew naturally under harsh field conditions. The Rosa ‘Tornedal’ origins, R. ‘Poppius’ and R. ‘Sipi’ were ranked the most suitable cultivars for northern landscaping. Overall, all of the studied roses succeeded fairly well. 相似文献
12.
Bald thigh syndrome (BTS) is a disease limited to Greyhound dogs. It is characterized clinically and grossly by bilateral hair loss on the lateral and caudal thighs. The cause of BTS is unknown but may be associated with hypothyroidism or hyperadrenocorticism. Samples of skin, thyroid glands, and adrenal glands from 43 Greyhound dogs with BTS were examined microscopically. Microscopic changes were characterized by dilatation of follicular infundibula, presence of catagen follicles and epidermal hyperplasia. Changes in the skin from these Greyhound dogs suggest an endocrinopathy as the cause; however, we were unable to confirm which one. 相似文献
13.
14.
Isolated water-soluble acidic arabinogalactans from Norway spruce and Scots pine heartwood were analysed and compared to
Siberian larch heartwood arabinogalactans. The carbohydrate monomer composition was determined by acid methanolysis and gas
chromatography, while structural studies were performed by 13C NMR spectroscopy and methylation analysis. The main structural features were found to be the same in the three types of
arabinogalactans. However, the structure of the arabinogalactans from spruce and pine were found slightly different from the
structure of larch arabinogalactans. The amount of single unit side-chains, consisting of arabinose and glucuronic acid units,
was higher in the spruce and pine arabinogalactans than in the larch arabinogalactans. The amount of glucuronic acid was higher
in the spruce arabinogalactans than in the pine arabinogalactans. The pine arabinogalactans had a higher amount of side chains
with more than two sugar units than the spruce arabinogalactans.
Received 30 December 1999 相似文献
15.
Mirkka Kotiaho Hannu Fritze Päivi Merilä Heli Juottonen Mirva Leppälä Jukka Laine Raija Laiho Kim Yrjälä Eeva-Stiina Tuittila 《Biology and Fertility of Soils》2010,46(6):567-575
We studied methanogen activity—measured by in vitro methane production potential and by detection of the messenger RNA (mRNA)
of a functional gene—in two boreal fens under high and deep water table (WT) level conditions resulting from a rainy growing
season and a dry growing season. The depth of the highest CH4-producing layers differed between the years. In the wet year, the highest CH4 production rate was around 20 cm below the mean WT. In the dry year, the highest rates were measured close to the peat surface,
well above the mean WT. The distribution of activity in the peat profiles of the two fens appeared to be site specific. Under
deep-WT conditions, CH4 production potential was generally lower than that under high-WT conditions. Detection of the mRNA of the methanogen-specific
mcrA gene indicated in situ methanogenesis in both water-saturated peat (below the WT) and unsaturated peat (above the WT). Analyses
of DNA-derived and mRNA-derived methanogen community structures showed greater similarity between those two in water-saturated
peat than in unsaturated peat. This suggested that favorable conditions promoted the activity of most members in methanogen
communities, but unfavorable conditions showed differences between distinct community members in adaptation to adverse conditions. 相似文献
16.
Nissinen R Lai FM Laine MJ Bauer PJ Reilley AA Li X De Boer SH Ishimaru CA Metzler MC 《Phytopathology》1997,87(7):678-684
ABSTRACT Strains of Clavibacter michiganensis subsp. sepedonicus, causal agent of bacterial ring rot of potato, showed marked differences in virulence on host plants. When infiltrated into tobacco leaves, virulent strains caused a rapid localized necrotic response (within 24 to 48 h) characteristic of the hypersensitive response (HR), whereas nonpathogenic strains did not. Concentrated cell-free culture supernatants (CCS) from virulent strains caused a necrotic reaction on tobacco, whereas CCS from nonpathogenic strains did not. The necrosis-inducing activity was heat stable and protease sensitive. Inhibitors of eukaryotic metabolism suppressed the necrotic reaction of tobacco to CCS. No necrotic response was observed when host plants were infiltrated with either cells or CCS from virulent strains. HR-inducing protein(s) from a virulent strain separated from the majority of other proteins on DEAE cellulose at 250 to 300 mM NaCl. Ammonium sulfate-precipitated proteins from a virulent strain produced a necrotic reaction at a total protein concentration of 18 mug/ml, whereas those from a nonpathogenic strain did not, even at a concentration of 180 mug/ml. We conclude that virulent strains of C. michiganensis subsp. sepedonicus elicit a typical HR in tobacco and secrete proteinaceous elicitor(s) of the nonhost HR. 相似文献
17.
Comment on "Retrieval practice produces more learning than elaborative studying with concept mapping" 总被引:1,自引:0,他引:1
Mintzes JJ Canas A Coffey J Gorman J Gurley L Hoffman R McGuire SY Miller N Moon B Trifone J Wandersee JH 《Science (New York, N.Y.)》2011,334(6055):453; author reply 453
Karpicke and Blunt (Reports, 11 February 2011, p. 772) reported that retrieval practice produces greater gains in learning than elaborative studying with concept mapping and concluded that this strategy is a powerful way to promote meaningful learning of complex concepts commonly found in science education. We question their findings on methodological and epistemological grounds. 相似文献
18.
Mia Huopalainen Eeva-Stiina Tuittila Ilkka Vanha-Majamaa Hannu Nousiainen Jukka Laine Harri Vasander 《Water, air, and soil pollution》2001,125(1):69-79
The effects of pollution on thecomposition of soil seed banks in four drained pinemires located along a pollution gradient in southernFinland were studied using the emergence method. Thespecies composition of the seed bank was compared withthe above ground vegetation. Dominant species in theseed banks were Calluna vulgaris, Betulaspp. and Ledum palustre. Seeds seemed to beviable despite a heavy pollution load. Especially inthe vicinity of the pollution source, seed bank andabove ground vegetation were weakly correlated. 相似文献
19.
Stefan Willför Andrey Pranovich Tarja Tamminen Juergen Puls Christiane Laine Anna Suurnäkki Bodo Saake Kati Uotila Helena Simolin Jarl Hemming Bjarne Holmbom 《Industrial Crops and Products》2009,29(2-3):571-580
Acid hydrolysis, acid methanolysis, and enzymatic hydrolysis were compared for depolymerization of five different plant materials containing uronic acids. The analyzed plant materials were oat spelt, wheat straw, spruce thermomechanical pulp, aspen stemwood, and totally chlorine-free (TCF) bleached hardwood kraft pulp. Furthermore, GC (using both HP-1 and HP-5 capillary columns and FID and MSD detectors), HPAEC-PAD, and HPAEC-Borate techniques were compared for subsequent analysis of the released monosaccharides. It was shown that acid methanolysis combined with GC analysis is a convenient method for obtaining the sugar unit composition and amount of non-crystalline polysaccharides in different plant materials. The methanolysis method was generally superior to the hydrolysis method for xylan- and uronic acid-containing samples. However, acid and enzymatic hydrolysis showed the highest recoveries for bleached chemical pulp samples. Acid hydrolysis is also required for crystalline polysaccharides, but the strong acid conditions evidently lead to degradation of labile sugars. The plant methanolysates were not suitable as such for analysis on an HPAEC-PAD system. For analysis of the total amount of sugar units, hence including cellulose, other non-crystalline hemicelluloses, and pectins, a combination of the methanolysis and hydrolysis methods is recommended. 相似文献
20.
Laine G Göbel C du Jardin P Feussner I Fauconnier ML 《Journal of agricultural and food chemistry》2006,54(15):5445-5452
Off-flavors frequently appear during the storage of potato flakes. Volatile profile analysis performed by solid-phase microextraction-gas chromatography-mass spectrometry revealed that hexanal is the main compound that appears during the storage period. Hexanal may be a degradation product of linoleic acid formed through linoleic acid hydroperoxide cleavage. Profiles of hexanal precursors were determined from potato flakes at different storage time points. Linoleic acid-derived oxylipins are predominant in potato flakes. The free oxylipins identified, in descending order, are as follows: hexanal, hydroxy polyunsaturated fatty (PUFAs), oxo PUFAs, divinyl ether PUFAs, and hydroperoxy PUFAs. However, the main oxylipins detected were esterified: esterified hydroxy, hydroperoxy, and oxo PUFAs. Oxylipins reveal different evolutions during the storage period. Chiral high-performance liquid chromatography analysis of the precursors of hexanal and other oxylipins revealed a racemic composition that supports the nonenzymatic formation of hexanal and most of the other oxylipins identified. 相似文献