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1.
Effects of elevated concentrations of ozone and carbon dioxide on the electrical impedance of leaves of silver birch (Betula pendula) clones 总被引：6，自引：0，他引：6
Effects of elevated concentrations of tropospheric ozone ([O3]) and carbon dioxide ([CO2]) on leaves of two silver birch (Betula pendula Roth) clones were monitored for three growing seasons (1998, 1999, 2000) by means of electrical impedance spectroscopy (EIS). The field trial with open-top chambers (OTCs) was conducted on two clones (Clone 4 and Clone 80) with five treatments and four independent replicates. Treatments were: (1) outside control, (2) chamber control, (3) 2x ambient [O3], (4) 2x ambient [CO2] and (5) 2x ambient [CO2] + 2x ambient [O3]. Fumigations started in 1999 and continued in 2000. Measurements were made in 1998 before the fumigations and thereafter EIS was carried out four times in each season. The impedance spectra of about 10 leaves from each tree at each time were measured at 42 frequencies between 80 and 1 MHz. Leaf spectra were modeled by a distributed circuit element model (DCE) (one DCE in series with a resistor), which yields the extracellular and intracellular resistances, the relaxation time and the distribution coefficient of the relaxation time. The EIS properties of the leaves changed significantly during the growing season when new leaves were expanding. The clones differed in their EIS properties. Clone 4 had a significantly higher extracellular resistance and distribution coefficient than Clone 80. The clones responded similarly to the fumigation treatments. Differences between treatments emerged especially during the second fumigation season in 2000. Elevated [O3] reduced both the relaxation time and the extracellular resistance, indicating cell membrane damage. Elevated [CO2] increased the intracellular resistance, indicating changes in symplastic composition. The biological interpretation of the EIS parameters in birch leaves is discussed. 相似文献
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Taina M Laine Tapani Lyytik?inen Maija Yliaho Marjukka Anttila 《Acta veterinaria Scandinavica》2008,50(1):21
Background
Post-weaning diarrhoea (PWD) is a significant gastrointestinal disease in pigs. It is considered a multifactorial disease associated with proliferation of enterotoxigenic Escherichia coli in the intestinal tract of affected pigs. The aim of this study was to analyse risk factors related to the occurrence of PWD on Finnish piglet producing farms.Methods
The data of a follow-up study of 73 conventional piglet producing farms was used in the case-control study. The selection of the 41 PWD case and 28 control farms was based on the use of antimicrobials for treating diarrhoea in weaned pigs and the answers related to the occurrence of diarrhoea after weaning in the questionnaire. Four intermediate farms were excluded from the statistical analysis.Altogether 39 factors related to herd characteristics, weaner pig management and pig health were studied. The median number of sows was 59.0 (IQR = 44.0; 74.5) and 52.5 (IQR = 36.8; 61.5) on the case and the control farms, respectively.The significances of the univariable associations between the explanatory variables and the outcome variable were tested, and in the multivariate analysis quasibinomial generalized linear models were applied.Results
An increased risk of PWD was associated with the regimen of twice a day feeding and feed restriction after weaning (P = 0.02; compared to feeding three or more meals a day or the use of ad libitum feeding) and with a higher number of sows on the farm (P = 0.02; risk increasing with increasing number of sows). Automatic temperature control was associated with a decreased risk of PWD (P = 0.03; compared to manual temperature control).Conclusion
Twice a day feeding of newly-weaned pigs should be avoided if the amount of feed given is restricted. Variation in ambient temperature should be minimized in housing of newly-weaned pigs and this can be achieved by using automatic temperature control. With increasing number of sows in the herds the risk of PWD increases and more attention should be paid to prevention of post-weaning diarrhoea. 相似文献4.
Outi Santala Pekka Lehtinen Emilia Nordlund Tapani Suortti Kaisa Poutanen 《Journal of Cereal Science》2011,54(2):187-194
Arabinoxylan (AX) has a major impact on the functional properties of wheat bran, and it has been shown that technological properties of bran can be improved by using endoxylanases. Enzymatic treatments are typically conducted at high water content. However, in industrial applications, low water content may be advantageous, especially when targeting dry end products. The aim of the study was to examine the impact of water content, ranging from 20 to 90%, on the efficiency of endoxylanase treatment of wheat bran. Interestingly, AX solubilisation was highest at the water contents of 40 and 90%. At water contents 50–80%, AX solubilisation was lower than at 40 and 90%. Furthermore, at low water content, less depolymerisation was detected. At water content of 40%, the bran-water mixture was transformed from powder-like into compact mass. Probably the compact consistency of the material enhanced AX solubilisation by increased breakdown of bran cell walls due to shear forces or via enhanced enzyme binding to the substrate. The results show that solubilisation of bran AX can also be efficiently performed at low water content. 相似文献
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Mika Nieminen Sakari Sarkkola Seppo Hellsten Hannu Marttila Sirpa Piirainen Tapani Sallantaus Ahti Lepistö 《Water, air, and soil pollution》2018,229(8):286
A recent study on nitrogen (N) and phosphorus (P) exports from drained peatland forests reported increasing concentrations over long time since their initial drainage. Concurrently, some other studies have suggested decreasing trends from drained peatland forests, particularly for P. To evaluate these contradictory findings, we re-analyzed past data and reviewed the literature related to temporal N and P concentration trends in runoff from drained peatland forests. Review of literature indicated that decreasing trends are found particularly in sites where initial P concentrations are high (>?50 μg P l?1), plausibly because of relatively recent fertilization and drainage operations. Decreasing N trends have been found in sites where ditch cleaning temporarily decreased concentrations. Increasing N trends have occurred in sites, where initial concentrations have been low, close to the levels found in pristine peatlands. Complementing past published data with additional data from sites with no recent forestry operations indicated that N concentrations correlated positively with drainage age (years since initial drainage), percentage of drained peatlands in the catchment (drainage proportion), and southern location of the study site. P concentrations correlated most strongly with drainage age. Our study indicated that four factors, in particular, need to be considered when interpreting nutrient concentration trends in runoff from drained peatlands: 1) management history, 2) drainage age, 3) drainage proportion, and 4) site location. Our results supported earlier conclusions in that the estimates which ignore the legacy effect of drainage remarkably underestimate the true impact of forestry on water courses in intensively drained regions. 相似文献
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Jerry A. Ivany Jennifer Lea Kevin V. McCully H. Tapani Kunelius 《Crop Protection》2002,21(10):991-995
Lolium multiflorum Lam. (annual ryegrass) is used extensively as a forage crop and seed is produced in several areas worldwide. Seed production has been shown to be commercially possible in Atlantic Canada but improved weed control is needed. Studies were conducted in two provinces (Prince Edward Island and New Brunswick) to determine the effects of the herbicides bentazon, bromoxynil/MCPA, dicamba/MCPA, thifensulfuron/tribenuron, 2,4-D and MCPA on weed control, L. multiflorum growth, seed yields and seed germination in 1998 and 1999. The herbicides MCPA, dicamba/MCPA and bromoxynil/MCPA as evaluated in these experiments provided acceptable control of the broad-leaved weeds present and had no effect on seed yield or seed germination. Although the thifensulfuron/tribenuron caused early foliar injury, the plants recovered and it provided excellent weed control. None of the herbicides affected seed germination. MCPA, dicamba/MCPA and bromoxynil/MCPA could be used to provide control of broad-leaved weeds and thifensulfuron/tribenuron could be used if growers were willing to accept some early injury and possible yield loss to obtain the improved weed control. 相似文献
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Clinical evaluation of medetomidine, a novel sedative and analgesic drug for dogs and cats 总被引：3，自引：0，他引：3
Tapani Vh-Vahe 《Acta veterinaria Scandinavica》1989,30(3):267-273
Medetomidine, a potent alpha 2-adrenoceptor agonist, was investigated in open, multicenter clinical trials with patients of various canine and feline breeds (1736 dogs and 678 cats). The purpose of the study was to find an optimal dose of medetomidine for sedation and analgesia in clinical practice and to study how well the intended procedure could be performed under the influence of the drug. The mean dose (i.m.) of medetomidine used for examinations, clinical procedures and minor surgical interventions was 40 micrograms/kg, and for radiography 30 micrograms/kg. In cats the dose was 80-110 micrograms/kg. On the doses chosen, almost all animals were recumbent and 72% of the dogs and 85% of the cats were in a slight anaesthetic stage, unable to rise. The evaluation of the overall suitability of medetomidine (% of cases) in different indications was "very satisfactory" or "satisfactory" in 95% of dogs and 81-96% of cats. Side effects reported were limited almost exclusively to vomiting and muscle jerking in dogs (12% and 0.5% of the cases) and to vomiting in cats (65%). Medetomidine seems to suffice for pharmacological restraint of dogs and cats. The concomitant use of medetomidine (80-100 micrograms/kg) and ketamine (7 mg/kg) in cats (n = 295) provided a good anaesthesia (20-40 min). The recovery was smooth. The present study shows that medetomidine provides an effective level of sedation and analgesia for clinical use. 相似文献
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Ultraviolet resonance Raman spectroscopy (UVRRS) was used to study the formation of aromatic and/or lignin-carbohydrate (LC)
structures at the reducing end groups of O-alkyl-substituted cellulose under conditions simulating the initial phase of kraft pulping. The derivatives studied were
methyl cellulose (MC) with degree of substitution (DS) of 1.64–1.95, carboxymethyl cellulose (CMC) with DS ∼0.6, and a lignin
model compound, creosol. The total alkali concentrations in the treatments were 0.1 M and 0.5 M and the sulfidities were 1%,
10%, and 30%. HS− ions and creosol are both strong nucleophiles and they compete for the hot-alkali-generated unsaturated electrophilic reaction
sites in the reducing end groups of the polysaccharides. The results indicated that conditions similar to those in the initial
phase of conventional kraft cooking (high OH− and low HS− ion concentrations) increased the aromatic nature of the end groups and conditions similar to those in the initial phase
of super batch cooking (low OH− and high HS− ion concentrations) partly inhibited the formation of aromatic and LC end groups. 相似文献
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Repo T Kalliokoski T Domisch T Lehto T Mannerkoski H Sutinen S Finér L 《Tree physiology》2005,25(8):1053-1062
Effects of the timing of soil thawing in the spring on Scots pine (Pinus sylvestris L.) were studied under controlled laboratory conditions. Sixteen 6-year-old saplings were lifted from the field, replanted in containers and placed in four treatments in controlled environment (CE) chambers with four replicate saplings per chamber. The saplings were held in the CE chambers during one simulated winter and one simulated growing season. The soil was frozen to -2 degrees C during a second simulated winter in the CE chambers, and the soil thawing treatments began at the end of the second simulated winter. Soil thawing began at various times before (no delay in thawing) and after (delay in thawing) chamber air conditions were changed from simulated winter to simulated summer. Delayed soil thawing subjected saplings to stress, with the severity of stress depending on the length of the delay in thawing. If there was no delay or only a short delay in soil thawing, stress was minor and reversible. A 2-week delay in soil thawing led to death of the saplings. Stress was apparent as decreases in the variable to maximal chlorophyll fluorescence ratio (Fv/Fm), chlorophyll a/b ratio and needle water potential. In needles of stressed saplings, apoplastic electrical resistance first decreased and then increased and there were anomalies in the electrical impedance spectra of the stems. Stress from the soil thawing treatments affected both root and shoot growth. 相似文献
10.
The effects of a heat treatment on the behaviour of extractives in softwood studied by FTIR spectroscopic methods 总被引：1，自引：0，他引：1
Mari?NuopponenEmail author Tapani?Vuorinen Saila?J?ms? Pertti?Viitaniemi 《Wood Science and Technology》2003,37(2):109-115
Scots pine battens were heat-treated at 100–240º C under saturated steam. Cross-sections of heat-treated battens were analysed using ATR and reflection FTIR microscopies. A typical absorption band of fats and waxes at 1740 cm-1 was detected on the sapwood edges in the temperature range of 100–160º C, indicating that fats and waxes moved along the axial parenchyma cells to the surface of the sapwood during the heat treatment. At the elevated temperatures (above 180° C) fats and waxes disappeared from the sapwood surface and were no longer detected with FTIR spectroscopy. Resin acids were detected at temperatures between 100 and 180º C in the middle of the battens. IR spectra of these spots showed a characteristic absorption band of resin acids at 1697 cm-1. At 200º C resin acids were not detected in the middle of the battens; however, resin acids were detected at distances of 500 and 600 mm from the midpoint of the battens and on the edges of battens. At temperatures above 200° C, resin acids had disappeared from the wood. 相似文献