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1.
In this paper, we investigate how the innovation expectations of public financiers are related to realized patents. The analysis is based on a novel data set of collaborative R&D projects subsidized by the Finnish Agency of Technology and Innovation (Tekes) and the European Regional Development Fund (ERDF) during the period 2000–2004. Innovation expectations are measured using reports submitted by Tekes experts during ex ante assessments of projects. Our probit model results reveal that Tekes' patent expectations are positively related to realized patents for projects led by private firms (but not by public organizations). For large organizations, Tekes' innovation expectations are better at predicting patenting.  相似文献   
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Nitric oxide (NO) and nitrous oxide (N2O) emissions were measured from experimental dung and urine patches placed on boreal pasture soil during two growing seasons and one autumn period until soil freezing. N2O emissions in situ were studied by a static chamber method. NO was measured with a dynamic chamber method using a NO analyser in situ. Mean emissions from the control plots were 47.6±4.5 μg N2ON m−2 h−1 and 12.6±1.6 μg NON m−2 h−1. N2O and NO emissions from urine plots (132±21.2 μg N2ON m−2 h−1 and 51.9±7.6 μg NON m−2 h−1) were higher than those from dung plots (110.0±20.1 μg N2ON m−2 h−1 and 14.7±2.1 μg NON m−2 h−1). There was a large temporal variation in N2O and NO emissions. Maximum N2O emissions were measured a few weeks after dung or urine application, whereas the maximum NO emissions were detected the following year. NO was responsible on average 14% (autumn) and 34% (summer) of total (NO+N2O)N emissions from the pasture soil. NO emissions increased with increasing soil temperature and with decreasing soil moisture. N2O emissions increased with increasing soil moisture, but did not correlate with soil temperature. Therefore we propose that N2O and NO were produced mainly during different microbial processes, i.e., nitrification and denitrification, respectively. The results show that the overall conditions and mechanism especially for emissions of NO are still poorly understood but that there are differences in the mechanisms regulating N2O and NO production.  相似文献   
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We studied the effects of root zone temperature (RZT) and nutrient availability on free sterols and phospholipids in the plasma membrane (PM) and on PM-ATPase activity in roots of 1-year-old Scots pine (Pinus sylvestris L.) seedlings during growth initiation in the spring. Seedlings were grown for 6 weeks in hydroponic cultures with low (0.5 mM N; LN) or high (3 mM N; HN) nutrient availability. The root zone was subjected to slow warming (SW) and fast warming (FW) treatments while maintaining similar air temperatures in both treatments. Decreases in the amount of phospholipids and in the phospholipid/free sterol ratio, an increase in the degree of saturation of phospholipid fatty acids and changes in free sterol composition were observed during root growth initiation. Changes in lipid composition of the PM associated with the cold deacclimation process were detected at RZTs above 9 degrees C. Nutrient availability affected the lipid composition of the PM only when RZT was increased slowly. When RZT increased from 4 to 6 degrees C in the SW treatment, the degree of saturation of phospholipid fatty acids decreased, especially in HN seedlings. The sitosterol/stigmasterol ratio remained higher in HN seedlings than in LN seedlings. After an RZT of 9 degrees C had been reached in the SW treatment, HN caused increases in the saturation of phospholipid fatty acids and root PM-ATPase activity, and a decrease in the phospholipid/free sterol ratio. Possible effects of changes in PM lipid composition on root growth and PM-ATPase activity are discussed.  相似文献   
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Trees have been increasingly considered as modular organisms, with individual shoots forming autonomous units that respond semi-independently to their surrounding environment. However, there is evidence for fairly strict hormonal control of tree crown development. Studies on the hydraulic architecture of trees suggest a closer functional connection between shoots and crown development than is postulated by the theory of branch autonomy. We studied how shoot growth pattern influences growth and crown architecture in young Scots pine trees simulated by the LIGNUM model assuming that (a) the growth of a shoot mainly depends on its light climate and (b) the growth of a shoot is influenced by its position within the crown. We determined shoot position within the crown based on a recently developed vigor index. The vigor index compares the relative axis cross-sectional area from the base of the tree to each shoot and gives a value of 1 to the pathway of the greatest cross-sectional area. All other shoots attain values between 0 and 1 depending on their cross-sectional areas and the cross-sectional areas of the branches leading there from the main axis. The shoot light climate is characterized by annually intercepted photosynthetically active radiation. We compared the results from simulations (a) and (b) against an independent data set. The addition of a within-shoot position index (the vigor index) to our simulation (simulation b) resulted in a more realistic tree form than that obtained with simulation (a) alone. We discuss the functional significance of the results as well as the possibilities of using an index of shoot position in simulations of crown architecture.  相似文献   
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Harvest residue decomposition can significantly contribute to nutrient and heavy metal exports to receiving water courses. This study monitors the nutrient and heavy metal dynamics in decaying Sitka spruce and lodgepole pine harvest residue needles on Atlantic blanket peat forests in the west of Ireland. Using the litterbag method, harvest residue was placed both within and between furrows in two uncut forest and two clear-cut sites. On the clear-cut sites, the litterbags were positioned outside the harvest residue piles (i.e. brash windrows). Over the 2-year monitoring period, the needles decomposed slower at the clear-cut sites than the uncut forest sites, with mass losses of 46–55 and 58–77 %, respectively. Approximately 20 % less phosphorous (P) was released from the decaying needles at the clear-cut sites, while nitrogen (N) was released only at the uncut sites. Tree species was a significant factor contributing to nutrient and heavy metal release and accumulation patterns, with higher concentrations of aluminium (Al), nickel (Ni), cadmium (Cd) and zinc (Zn) in the decaying spruce needles than in pine. Conversely, the spruce needles showed accelerated depletion of calcium (Ca) and magnesium (Mg) relative to the pine. The harvest residue needle positioning (inside furrow/between furrows) and the site soil characteristics contributed significantly to Al transformations in spruce needles and iron (Fe) in both spruce and pine needles, with more accumulation occurring inside the furrows where Al and Fe contents of the peat were high. Manganese (Mn) was released from the needles in three of the four sites with a total release of over 90 % within 2 years. In the remaining site, where the Mn content of the peat was high, an accumulation of Mn in the needles was observed. The decomposition of needles on blanket peat catchments may be a significant source of P to receiving water courses, owing to their fast release of P, but not a likely source for N export.  相似文献   
10.
This study investigates the climate impact on the radial increment of pedunculate oak (Quercus robur L.) in Estonia at the species’ northern distribution limit. Tree-ring width series of 162 living oaks were compiled into three regional chronologies—western (1646–2008), northeastern (1736–2011), and southeastern Estonia (1912–2011). Although these regional growth patterns are similar to each other and even to the growth patterns in adjacent regions, spatial differences in growth responses to climate were established. Thus, oaks growing on shallow soil in western Estonia are positively influenced by summer (June–August) precipitation, and oaks on the deeper soil in northeastern Estonia are favoured by June temperature, while oaks in the southeastern part of the country depend on both July precipitation and temperature. These relationships are pronounced especially in pointer years. However, due to the impact of regional weather fluctuations on tree growth, there is a lack of correspondence between the local and the pan-European pointer years. In addition, our research presents the first tree-ring-based palaeoclimatic reconstruction for the country. Although the created model has relatively low predictive skill describing less than a quarter of the variance in actual summer precipitation in western Estonia, it has passable capacity of detecting past rainfall extremes.  相似文献   
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