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Jüri-Ott Salm Martin Maddison Sille Tammik Kaido Soosaar Jaak Truu Ülo Mander 《Hydrobiologia》2012,692(1):41-55
The aim of this study is to estimate emissions of greenhouse gases CO2, CH4 and N2O, and the effects of drainage and peat extraction on these processes, in Estonian transitional fens and ombrotrophic bogs. Closed-chamber-based sampling lasted from January to December 2009 in nine peatlands in Estonia, covering areas with different land-use practices: natural (four study sites), drained (six sites), abandoned peat mining (five sites) and active peat mining areas (five sites). Median values of soil CO2 efflux were 1,509, 1,921, 2,845 and 1,741 kg CO2-C ha?1 year?1 from natural, drained, abandoned and active mining areas, respectively. Emission of CH4-C (median values) was 85.2, 23.7, 0.07 and 0.12 kg ha?1 year?1, and N2O-N ?0.05, ?0.01, 0.18 and 0.19 kg ha?1 year?1, respectively. There were significantly higher emissions of CO2 and N2O from abandoned and active peat mining areas, whereas CH4 emissions were significantly higher in natural and drained areas. Significant Spearman rank correlation was found between soil temperature and CO2 flux at all sites, and CH4 flux with high water level at natural and drained areas. Significant increase in CH4 flux was detected for groundwater levels above 30 cm. 相似文献
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E E Vasar A Kh Soosaar M O Ma?mets L Kh Allikmets 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(11):583-585
The authors have used behavioural and radioreceptor methods of investigation, that helped to find correlates of the behavioural phenomena on the receptor level. 相似文献
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In vivo expansion of functionally integrated GABAergic interneurons by targeted increase in neural progenitors 下载免费PDF全文
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E E Vasar L Kh Allikmets A Kh Soosaar A E Lang 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1987,37(4):696-702
In experiments on male mice and rats, long-term haloperidol administration (0.25 mg/kg twice a day during 15 days) significantly changed behavioural effects of caerulein, an agonist of CCK-8 receptors. As a rule, the effects of caerulein were reduced or inverted; only long-term antagonism with amphetamine motor excitation in rats increased after the cessation of haloperidol administration. The decrease or inversion of caerulein's effects was connected with reduction of high-affinity dopamine2- and low-affinity CCK-8 receptors' density, reflecting the inhibition of some interneurons' activity in subcortical forebrain structures after haloperidol treatment. A more pronounced inhibition of dopamine's release by caerulein was the reason for the increased antiamphetamine action after long-term haloperidol treatment. It seems possible that both above mechanisms are involved in the antipsychotic action of haloperidol. 相似文献
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Alvarado-Vázquez MA R Foroughbakhch MA Guzmán- Lucio A Rocha-Estrada JL Hernández-Piñero ML Cárdenas-Ávila BM Soto-García 《Phyton》2015,84(1):70-79
Candelilla (Euphorbia antisiphylitica Zucc.) is a very important plant resource in the arid lands of Northern Mexico. This is because the wax content coating the stem has unique properties which have been useful for multiple applications in the food industry, electronics, cosmetics, etc. However, the intensive exploitation of this resource has caused a great decrease in the populations of this species making necessary to consider strategies for their conservation and sustainable use. One of the primary needs with regeneration purposes is to know their reproductive processes, particularly the biotic and/or abiotic factors that determine the viability and germination of seeds. The present study evaluated the (1) germination and seed viability in relation to the ripeness degree of the fruit at the time of collection, (2) weight of the seed (low, medium and high), and (3) storage time (1, 3, and 5 months). Fruits from four locations, two in the State of Coahuila (Las Coloradas and Candela) and two in the State of Nuevo Leon (Icamole 1 and Icamole 2), were collected. Three germination assays were carried out corresponding to each month of storage. Seed viability was determined by the tetrazolium test. The average weight of the candelilla seeds was 0.0029 ± 0.0010 g, with extreme average values of 0.0018 ± 0.0006 g at Las Coloradas and 0.0036 ± 0.0010 g in Icamole 2. Those seeds with heavier weight obtained from red fruits and with 1 month of storage showed the highest average percentage of viability (66.87 ± 24.19%). At the same time, seeds with around average weight, obtained from red fruits and five months of storage, showed the highest average germination percentage (50.00 ± 9.42%). 相似文献