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631.
Piritta Pyörälä Heli Peltola Harri Strandman Kilpeläinen Antti Asikainen Antti Kirsti Jylhä Seppo Kellomäki 《Bioenergy Research》2014,7(1):279-294
We analyzed the effects of management on the economic profitability of forest biomass production and carbon neutrality of bioenergy use in Norway spruce (Picea abies L. Karst) stands under the changing climate. We employed a forest ecosystem model and life cycle assessment tool. In particular, we studied the effects of thinning, nitrogen fertilization, and rotation length on: (1) the production of timber and energy biomass, and its economic profitability (net present value), (2) carbon stock in the forest ecosystem and carbon balance in forestry, and (3) carbon dioxide (CO2) emissions from the use of biomass in energy production. Results showed that the current Finnish baseline management with and without nitrogen fertilization resulted in the highest mean annual timber production and net present value (NPV) for long rotations (60 to 80 years), regardless of climate scenario. Mean annual production of energy biomass was enhanced by increasing stocking by 20–30 % compared to the baseline management, and/or use of nitrogen fertilization. Such management gave lower CO2 emissions per unit of energy compared to the baseline management, as the carbon stock in the forest ecosystem and the carbon balance in forestry increased. Overall, the carbon neutrality and net present value were, on average, the highest in the baseline management or with a 20 % increase in stocking, with nitrogen fertilization and 60- to 80-year rotation lengths, regardless of the climate applied. However, it was not possible to simultaneously maximize the NPV of forest biomass production and the carbon neutrality of bioenergy use. 相似文献
632.
Antti?OksanenEmail author Kjetil??sbakk Marja?Raekallio Mauri?Nieminen 《Acta veterinaria Scandinavica》2014,56(1):76
Background
Overwintering (breeding) reindeer (Rangifer tarandus tarandus) are commonly treated with ivermectin against parasitic infestations once yearly in autumn-winter roundups. The only preparations registered to reindeer are those for subcutaneous injection. However, also oral extra-label ivermectin administration is used. Twenty-six, 8-month-old reindeer calves were randomly allocated into three groups. Group 1 (n = 9) received oral ivermectin mixture (Ivomec® vet mixt. 0.8 mg/ml, oral ovine liquid drench formulation), Group 2 (n = 9) oral ivermectin paste (Ivomec® vet 18.7 mg/g equine paste), and Group 3 (n = 8) subcutaneous injection of ivermectin (Ivomec® 10 mg/ml vet inj.), each group at a dose of 200 μg/kg body weight. Blood samples were collected at treatment and at days 1, 2, 3, 6, 9 and 16 post treatment. Plasma concentrations of ivermectin were determined by high-pressure liquid chromatography (HPLC) with fluorescence detection.Results
The peak plasma concentration (Cmax) was reached by 2 days after each treatment. The Cmax and Area Under Curve (AUC) differed significantly between the groups: Cmax was 30.2 ± 3.9, 14.9 ± 5.7 and 63.1 ± 13.1 ng/ml, and AUC∞ was 2881 ± 462, 1299 ± 342 and 6718 ± 1620 ng*h/ml for groups 1, 2 and 3, respectively (mean ± standard deviation).Conclusions
The differences in plasma concentrations of ivermectin are concomitant with earlier observed differences in antiparasitic efficacy, which discounts the use of the equine paste in reindeer in favour of the oral ovine liquid drench formulation, or preferably, the reindeer-registered subcutaneous injection formulation.633.
Esther J. Smits Antti J. Tolonen Luc Cluitmans Mark van Gils Bernard A. Conway Rutger C. Zietsma Klaus L. Leenders Natasha M. Maurits 《PloS one》2014,9(5)
Objective
To assess whether standardized handwriting can provide quantitative measures to distinguish patients diagnosed with Parkinson''s disease from age- and gender-matched healthy control participants.Design
Exploratory study. Pen tip trajectories were recorded during circle, spiral and line drawing and repeated character ‘elelelel’ and sentence writing, performed by Parkinson patients and healthy control participants. Parkinson patients were tested after overnight withdrawal of anti-Parkinsonian medication.Setting
University Medical Center Groningen, tertiary care, the Netherlands.Participants
Patients with Parkinson''s disease (n = 10; mean age 69.0 years; 6 male) and healthy controls (n = 10; mean age 68.1 years; 6 male).Interventions
Not applicable.Main Outcome Measures
Movement time and velocity to detect bradykinesia and the size of writing to detect micrographia. A rest recording to investigate the presence of a rest-tremor, by frequency analysis.Results
Mean disease duration in the Parkinson group was 4.4 years and the patients were in modified Hoehn-Yahr stages 1–2.5. In general, Parkinson patients were slower than healthy control participants. Median time per repetition, median velocity and median acceleration of the sentence task and median velocity of the elel task differed significantly between Parkinson patients and healthy control participants (all p<0.0014). Parkinson patients also wrote smaller than healthy control participants and the width of the ‘e’ in the elel task was significantly smaller in Parkinson patients compared to healthy control participants (p<0.0014). A rest-tremor was detected in the three patients who were clinically assessed as having rest-tremor.Conclusions
This study shows that standardized handwriting can provide objective measures for bradykinesia, tremor and micrographia to distinguish Parkinson patients from healthy control participants. 相似文献634.
635.
Bichlmaier I Siiskonen A Kurkela M Finel M Yli-Kauhaluoma J 《Biological chemistry》2006,387(4):407-416
The stereoselective binding and transformation of optically pure bicyclic alcohols by human UDP-glucuronosyltransferases from subfamily 2B were investigated. The enantiomers of 1-indanol, 1-tetralol, and 1-benzosuberol were synthesized by asymmetric Corey-Bakshi-Shibata reduction and subjected to glucuronidation assays. The alcohols studied were primarily glucuronidated by UGT2B7 and UGT2B17. The catalytic transformation by UGT2B17 was highly stereoselective, favoring conjugation of the (R)-enantiomers. UGT2B7, on the other hand, did not exhibit stereoselectivity toward 1-benzosuberol, the best substrate in this series. To assess binding affinities to the enzymes, the six different compounds were tested for their efficiency as inhibitors of either UGT2B7 or UGT2B17. The results of the latter analyses indicated that the affinities of both enantiomers of each pair towards UGT2B7 and UGT2B17 were of the same order of magnitude. Therefore, the findings of this study suggest that the spatial arrangement of the hydroxy group plays an important role in the glucuronic acid transfer reaction, but not necessarily in substrate binding to the UGTs. 相似文献
636.
637.
Statistical multivariate metabolite profiling for aiding biomarker pattern detection and mechanistic interpretations in GC/MS based metabolomics 总被引:1,自引:0,他引:1
Elin Pohjanen Elin Thysell Johan Lindberg Ina Schuppe-Koistinen Thomas Moritz Pär Jonsson Henrik Antti 《Metabolomics : Official journal of the Metabolomic Society》2006,2(4):257-268
A strategy for robust and reliable mechanistic statistical modelling of metabolic responses in relation to drug induced toxicity
is presented. The suggested approach addresses two cases commonly occurring within metabonomic toxicology studies, namely;
1) A pre-defined hypothesis about the biological mechanism exists and 2) No such hypothesis exists. GC/MS data from a liver
toxicity study consisting of rat urine from control rats and rats exposed to a proprietary AstraZeneca compound were resolved
by means of hierarchical multivariate curve resolution (H-MCR) generating 287 resolved chromatographic profiles with corresponding
mass spectra. Filtering according to significance in relation to drug exposure rendered in 210 compound profiles, which were
subjected to further statistical analysis following correction to account for the control variation over time. These dose
related metabolite traces were then used as new observations in the subsequent analyses. For case 1, a multivariate approach,
named Target Batch Analysis, based on OPLS regression was applied to correlate all metabolite traces to one or more key metabolites
involved in the pre-defined hypothesis. For case 2, principal component analysis (PCA) was combined with hierarchical cluster
analysis (HCA) to create a robust and interpretable framework for unbiased mechanistic screening. Both the Target Batch Analysis
and the unbiased approach were cross-verified using the other method to ensure that the results did match in terms of detected
metabolite traces. This was also the case, implying that this is a working concept for clustering of metabolites in relation
to their toxicity induced dynamic profiles regardless if there is a pre-existing hypothesis or not. For each of the methods
the detected metabolites were subjected to identification by means of data base comparison as well as verification in the
raw data. The proposed strategy should be seen as a general approach for facilitating mechanistic modelling and interpretations
in metabolomic studies. 相似文献
638.
The objectives of this study were to investigate impact of stump and slash removal on growth and mycorrhization of Picea abies seedlings outplanted on a forest clear-cut. Four non-replicated site preparation treatments included: (1) mounding (M), (2)
removal of stumps (K), (3) mounding and removal of logging slash (HM) and (4) removal of logging slash and stumps (HK). Results
showed that height increment of the seedlings was highest in K and lowest in M after the third growing season, and similar
pattern remained after the fourth season. Ectomycorrhizal (ECM) colonisation of seedling roots was highest in M (96.6%) and
lowest in K (72.3%), and even in HK (76.0%) and HM (76.3%). Morphotyping and sequencing of internal transcribed spacer of
fungal ribosomal DNA revealed a total of 13 ECM species. Among those, Thelephora terrestris and Cenococcum geophilum were the most common, found on 27.4% and 26.3% of roots, respectively. The rest of species colonised 26.6% of roots. Richness
of ECM species was highest in M (10 species) and lowest in K (three species). Consequently, stump and slash removal from clear-felled
sites had a positive effect on growth of outplanted spruce seedlings, but negative effect on their mycorrhization. This suggests
that altered soil conditions due to site disturbance by stump and slash removal might be more favourable for tree growth than
more abundant mycorrhization of their root systems in less disturbed soil. 相似文献
639.
Hautala AJ Rankinen T Kiviniemi AM Mäkikallio TH Huikuri HV Bouchard C Tulppo MP 《American journal of physiology. Heart and circulatory physiology》2006,291(1):H459-H466
The determinants of heart rate (HR) recovery after exercise are not well known, although attenuated HR recovery is associated with an increased risk of cardiovascular mortality. Because acetylcholine receptor subtype M2 (CHRM2) plays a key role in the cardiac chronotropic response, we tested the hypothesis that, in healthy individuals, the CHRM2 gene polymorphisms might be associated with HR recovery 1 min after the termination of a maximal exercise test, both before and after endurance training. The study population consisted of sedentary men and women (n = 95, 42 +/- 5 yr) assigned to a training (n = 80) or control group (n = 15). The study subjects underwent a 2-wk laboratory-controlled endurance training program, which included five 40-min sessions/wk at 70-80% of maximal HR. HR recovery differed between the intron 5 rs324640 genotypes at baseline (C/C, -33 +/- 10; C/T, -33 +/- 7; and T/T, -40 +/- 11 beats/min, P = 0.008). Endurance training further strengthened the association: the less common C/C homozygotes showed 6 and 12 beats/min lower HR recovery than the C/T heterozygotes or the T/T homozygotes (P = 0.001), respectively. A similar association was found between A/T transversion at the 3'-untranslated region of the CHRM2 gene and HR recovery at baseline (P = 0.025) and after endurance training (P = 0.005). These data suggest that DNA sequence variation at the CHRM2 locus is a potential modifier of HR recovery in the sedentary state and after short-term endurance training in healthy individuals. 相似文献
640.
Antti Tuori Hannu Uusitalo Lars-Eric Thornell Toshimichi Yoshida Ismo Virtanen 《The Histochemical journal》1999,31(4):245-252
Tenascin-X has been studied in developing and adult rat eye and in foetal and adult human eyes, using immunohistochemistry and frozen sections. The data were compared with the distribution of tenascin-C. The immunoreactivity for tenascin-X was seen in a basement membrane-like feature in different structures of embryonic (E) day 16–17 rat eyes. Postnatal (P) day 2 and older rat eyes showed immunoreactivity for tenascin-X in different connective tissues. In the epithelial basement membrane zone of the cornea, immunostaining was positive in P5 eyes, negative in P10 and P15 eyes and again positive in P30 and adult eyes. In the 20-week-old human foetus, immunoreactivity for the tenascin was seen in the posterior parts of the conjunctival stroma adjacent to the sclera and in a basement membrane-like fashion in anterior conjunctiva. In the adult human eye, immunoreactivity for tenascin-X was seen in the anterior one-third stroma of cornea as thin fibrils, in the stroma of the limbus and conjunctiva, and in blood vessels. Immunostaining for tenascin-C was seen in the posterior aspect of the further cornea, and in mesenchyme adjacent to cornea in E16–17 rat eyes. Corneal keratocytes and Descemet's membrane showed immunoreactivity for tenascin-C in P2–P15 rat eyes. Sclera and the junction of the cornea, and sclera expressed tenascin-C in P2 and older rat eyes. In human foetal eyes, immunostaining for tenascin-C was seen in the anterior parts of the corneal stroma, in the basement membrane zone and Bowman's membrane of the corneal epithelium, in the posterior one-fifth of the corneal stroma and the sclera starting from the junction of the cornea and sclera. In normal human adult eyes, immunostaining for tenascin-X was seen in the anterior one-third stroma of cornea, in the stroma of limbus and conjunctiva, and in blood vessels. The association of tenascin-X and basement membranes in early development evokes a question of its potential function in the development of the basement membrane. The results also suggest the association of tenascin-X with connective tissue development as well as the association of tenascin-C with the migration of keratocytes during the development of the corneal stroma. 相似文献