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571.
Antti Kilpeläinen Heli Peltola Ismo Rouvinen Seppo Kellomäki 《Trees - Structure and Function》2006,20(1):16-27
The aim of this study was to analyse and model the effects of elevated temperature and carbon dioxide concentration on daily
height growth of 20-year-old Scots pines (Pinus sylvestris L.). The trees were grown with a low nitrogen supply in closed chambers with a factorial combination of two temperature regimes
(ambient and elevated) and two carbon dioxide concentrations (ambient and twice ambient). The temperature elevation corresponded
to the predicted increase at the site after a doubling in atmospheric CO2. The height growth of Scots pines was first empirically studied in terms of its onset, cessation and duration, and the allocation
of daily height growth within the growing period in 2000 and 2001, and then a model predicting daily height growth as a function
of daily temperature and temperature sum was developed. The empirical results showed elevated temperature to be the dominant
variable explaining variation in daily height growth. Elevated temperature also hastened both the onset and cessation of height
growth, and the temperature sums for both of them were higher in the elevated than in the ambient temperature treatments.
The daily variation in height growth could also be explained by the daily mean temperature in the model. Elevated CO2 concentration had no effect on the onset, cessation or duration of height growth. The amount of height growth was not affected
by any of the treatments. 相似文献
572.
573.
Abstract Death-rate determinations indicated that a temperature a few tenths of a degree higher than Tmax was more deleterious to Klebsiella terrigena (ATCC 33257) than a somewhat higher temperature. The death rate at 40°C (Tmax + 0.5°C) was approximately 0.2 log units per h but about 0.01 log units per h between 42°C and 44°C. Sequential temperature-gradient and constant temperature incubations showed the same phenomenon qualitatively among 14 Enterobacteriaceae strains representing different species. 相似文献
574.
Purpose
The cities merit special attention in global warming since they produce up to 80% of the global greenhouse gas emissions. Even though this has been widely acknowledged, only few papers exist that have studied cities holistically from a demand, i.e., consumption, perspective. The study presents a detailed analysis of the carbon footprint of two metropolitan cities from a consumption perspective. With the analysis of consumer carbon footprints (carbon consumption), the distribution of emissions in the key source categories is presented and compared. 相似文献575.
Natunen Jari; Seppo Antti; Helin Jari; Reinhold Bruce B.; Rabina Jarkko; Costello Catherine E.; Renkonen Ossi 《Glycobiology》1997,7(5):711-718
A novel saccharide was synthesized by incubating globo-N-tetraose,GalNAcß13Gal 相似文献
576.
577.
578.
Pyry Helkkula Tuomo Kiiskinen Aki S. Havulinna Juha Karjalainen Seppo Koskinen Veikko Salomaa Mark J. Daly Aarno Palotie Ida Surakka Samuli Ripatti FinnGen 《PLoS genetics》2021,17(4)
Protein-truncating variants (PTVs) affecting dyslipidemia risk may point to therapeutic targets for cardiometabolic disease. Our objective was to identify PTVs that were associated with both lipid levels and the risk of coronary artery disease (CAD) or type 2 diabetes (T2D) and assess their possible associations with risks of other diseases. To achieve this aim, we leveraged the enrichment of PTVs in the Finnish population and tested the association of low-frequency PTVs in 1,209 genes with serum lipid levels in the Finrisk Study (n = 23,435). We then tested which of the lipid-associated PTVs were also associated with the risks of T2D or CAD, as well as 2,683 disease endpoints curated in the FinnGen Study (n = 218,792). Two PTVs were associated with both lipid levels and the risk of CAD or T2D: triglyceride-lowering variants in ANGPTL8 (-24.0[-30.4 to -16.9] mg/dL per rs760351239-T allele, P = 3.4 × 10−9) and ANGPTL4 (-14.4[-18.6 to -9.8] mg/dL per rs746226153-G allele, P = 4.3 × 10−9). The risk of T2D was lower in carriers of the ANGPTL4 PTV (OR = 0.70[0.60–0.81], P = 2.2 × 10−6) than noncarriers. The odds of CAD were 47% lower in carriers of a PTV in ANGPTL8 (OR = 0.53[0.37–0.76], P = 4.5 × 10−4) than noncarriers. Finally, the phenome-wide scan of the ANGPTL8 PTV showed that the ANGPTL8 PTV carriers were less likely to use statin therapy (68,782 cases, OR = 0.52[0.40–0.68], P = 1.7 × 10−6) compared to noncarriers. Our findings provide genetic evidence of potential long-term efficacy and safety of therapeutic targeting of dyslipidemias. 相似文献
579.
Mikko P. Turunen Einari Aavik Seppo Ylä-Herttuala 《Biochimica et Biophysica Acta (BBA)/General Subjects》2009
The contribution of epigenetic mechanisms to cardiovascular diseases remains poorly understood. Hypomethylation of genomic DNA is present in human atherosclerotic lesions and methylation changes also occur at the promoter level of several genes involved in the pathogenesis of atherosclerosis, such as extracellular superoxide dismutase, estrogen receptor-α, endothelial nitric oxide synthase and 15-lipoxygenase. So far, no clear data is available about histone modification marks in atherosclerotic lesions. It remains unclear whether epigenetic changes are causally related to the pathogenetic features, such as clonal proliferation of lesion smooth muscle cells, lipid accumulation and modulation of immune responses in the lesions, or whether they merely represent a consequence of the ongoing pathological process. However, epigenetic changes could at least partly explain poorly understood environmental and dietary effects on atherogenesis and the rapid increases and decreases in the incidence of coronary heart disease observed in various populations. RNAi mechanisms may also contribute to the epigenetic regulation of vascular cells. Therapies directed towards modification of the epigenetic status of vascular cells might provide new tools to control atherosclerosis-related cardiovascular diseases. 相似文献
580.
We studied the effect of winter rank on survival rate and reproductive success in Willow Tits Parus montanus, a resident passerine living in dominance-structured flocks during the nonbreeding season, in 6 years. Winter survival was dependent on both the birds' age and rank. Adults survived better than first-year birds, and within first-year males, dominants survived better than subordinates. In other sex and age classes, rank did not contribute to survival. Although first-year males were in excess among nonbreeders, no connection existed between breeding status and rank. Female rank did not explain the variation in the start of laying, clutch size, number of fledglings or recruit production. We conclude that social status in Willow Tits affects individual fitness mainly through rank-dependent survival. Acquiring a high rank position seems to be most important for first-year birds, especially first-year males. 相似文献