13 research outputs found
Meta-analysis results of common SNPs of miRNAs.
<p>Results are shown as OR 95% CI; M1: homozygote comparison; M2 heterozygote comparison; M3: dominant model; M4: recessive model;</p>*<p>for significant difference.</p
miRNA-SNPs and lung cancer.
*<p>significant association;</p><p>a: different results between screening set and validation set;</p><p>b: HR and 95% CI estimated form Kaplan-Meier curve;</p><p>c: data from the validation set; d: data from low-dose smokers of Boston case-control study.</p
Forrest plot of miRNA-196a2 rs11614913 (dominant model).
<p>Estimated by random-effect model (CC+CT vs. TT).</p
Influences of Land Use/Cover Types on Nitrous Oxide Emissions during Freeze-Thaw Periods from Waterlogged Soils in Inner Mongolia
<div><p>Nitrous oxide emissions during freeze/thaw periods contribute significantly to annual soil N<sub>2</sub>O emissions budgets in middle- and high-latitude areas; however, the freeze/thaw-related N<sub>2</sub>O emissions from waterlogged soils have hardly been studied in the Hulunber Grassland, Inner Mongolia. For this study, the effects of changes in land use/cover types on N<sub>2</sub>O emissions during freeze–thaw cycles were investigated to more accurately quantify the annual N<sub>2</sub>O emissions from grasslands. Soil cores from six sites were incubated at varying temperature (ranging from −15 to 10°C) to simulate freeze–thaw cycles. N<sub>2</sub>O production rates were low in all soil cores during freezing periods, but increased markedly after soil thawed. Mean rates of N<sub>2</sub>O production differed by vegetation type, and followed the sequence: <i>Leymus chinensis</i> (LC) and <i>Artemisia tanacetifolia</i> (AT) steppes > LC steppes ≥ <i>Stipa baicalensis</i> (SB) steppes. Land use types (mowing and grazing) had differing effects on freeze/thaw-related N<sub>2</sub>O production. Grazing significantly reduced N<sub>2</sub>O production by 36.8%, while mowing enhanced production. The production of N<sub>2</sub>O was related to the rate at which grassland was mowed, in the order: triennially (M3) > once annually (M1) ≥ unmown (UM). Compared with the UM control plot, the M3 and M1 mowing regimes enhanced N<sub>2</sub>O production by 57.9% and 13.0% respectively. The results of in situ year-round measurements showed that large amounts of N<sub>2</sub>O were emitted during the freeze–thaw period, and that annual mean fluxes of N<sub>2</sub>O were 9.21 μg N<sub>2</sub>O-N m<sup>-2</sup> h<sup>-1</sup> (ungrazed steppe) and 6.54 μg N<sub>2</sub>O-N m<sup>-2</sup> h<sup>-1</sup> (grazed steppe). Our results further the understanding of freeze/thaw events as enhancing N<sub>2</sub>O production, and confirm that different land use/cover types should be differentiated rather than presumed to be equivalent, regarding nitrous oxide emission. Even so, further research involving multi-year and intensive measurements of N<sub>2</sub>O emission is still needed.</p></div
Mean N<sub>2</sub>O production rates (μg kg<sup>-1</sup> h<sup>-1</sup>) along the profile (0–15 cm) of soil cores: From UM (a, b), M1 (c, d), and M3 (e, f) over the entire incubation period (n = 3); Freezing periods: a, c, e; Thawing periods: b, d, f.
<p>Lowercase letters indicate significant differences (P < 0.05) between samples from different soil depths.</p
Cumulative productions of N<sub>2</sub>O along the whole soil profile (0–15 cm) at different temperature during the freeze–thaw cycles of different land use/cover type<sup>a</sup>.
<p><sup>a</sup>The duration is 7 days at each temperature. Uppercase letters indicates significant differences (P<0.05) among different soil types. Lowercase letters indicates significant differences (P<0.05) among different temperature (mean ± SE, n = 3)</p><p>Cumulative productions of N<sub>2</sub>O along the whole soil profile (0–15 cm) at different temperature during the freeze–thaw cycles of different land use/cover type<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0139316#t002fn001" target="_blank"><sup>a</sup></a>.</p
General soil properties of the soil sampling sites<sup>a</sup>.
<p><sup>a</sup>Abbreviations are as follows: BD, bulk density; SOM, soil organic matter; UM, un-mowed grassland; M1, mowed once annually; M3, mowed once triennially; LUG, <i>Leymus chinensis</i> grassland; SUG, <i>Stipa baicalensis</i> grassland; SG, <i>Stipa baicalensis</i> grazed grassland</p><p>General soil properties of the soil sampling sites<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0139316#t001fn001" target="_blank"><sup>a</sup></a>.</p
Soil conditions at the start and end of the freeze/thaw incubation experiments: Average total nitrogen (TN) (a), Soil organic matter (SOM) (b), NH<sub>4</sub><sup>+</sup> (c), NH<sub>4</sub><sup>+</sup> content at different soil depths for M1 (d), and NO<sub>3</sub><sup>−</sup> (e), NO<sub>3</sub><sup>−</sup> content at different soil depths for SUG (f).
<p>The vertical bars indicate standard errors of three replicates.</p