1. |
- Ding, Jinzhi, et al.
(author)
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Decadal soil carbon accumulation across Tibetan permafrost regions
- 2017
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In: Nature Geoscience. - 1752-0894 .- 1752-0908. ; 10:6, s. 420-424
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Journal article (peer-reviewed)abstract
- Permafrost soils store large amounts of carbon. Warming can result in carbon release from thawing permafrost, but it can also lead to enhanced primary production, which can increase soil carbon stocks. The balance of these fluxes determines the nature of the permafrost feedback to warming. Here we assessed decadal changes in soil organic carbon stocks in the active layer-the uppermost 30 cm-of permafrost soils across Tibetan alpine regions, based on repeated soil carbon measurements in the early 2000s and 2010s at the same sites. We observed an overall accumulation of soil organic carbon irrespective of vegetation type, with a mean rate of 28.0 g Cm-2 yr(-1) across Tibetan permafrost regions. This soil organic carbon accrual occurred only in the subsurface soil, between depths of 10 and 30 cm, mainly induced by an increase of soil organic carbon concentrations. We conclude that the upper active layer of Tibetan alpine permafrost currently represents a substantial regional soil carbon sink in a warming climate, implying that carbon losses of deeper and older permafrost carbon might be offset by increases in upper-active-layer soil organic carbon stocks, which probably results from enhanced vegetation growth.
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2. |
- He, Yafang, et al.
(author)
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Metabolomic Changes Upon Conjugated Linoleic Acid Supplementation and Predictions of Body Composition Responsiveness
- 2022
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In: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 107:9, s. 2606-2615
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Journal article (peer-reviewed)abstract
- Context Conjugated linoleic acid (CLA) may optimize body composition, yet mechanisms underlining its benefits are not clear in humans. Objective We aimed to reveal the CLA-induced changes in the plasma metabolome associated with body composition improvement and the predictive performance of baseline metabolome on intervention responsiveness. Methods Plasma metabolome from overnight fasted samples at pre- and post-intervention of 65 participants in a 12-week randomized, placebo-controlled trial (3.2 g/day CLA vs 3.2 g/day sunflower oil) were analyzed using untargeted LC-MS metabolomics. Mixed linear model and machine learning were applied to assess differential metabolites between treatments, and to identify optimal panel (based on baseline conventional variables vs metabolites) predicting responders of CLA-derived body composition improvement (increased muscle variables or decreased adiposity variables) based on dual-energy x-ray absorptiometry. Results Compared with placebo, CLA altered 57 metabolites (P
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3. |
- Lai, Jianwen, et al.
(author)
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Calcium Oxide Adsorption of Gas Phase PCDD/Fs and Its Impact on the Adsorption Properties of Activated Carbon
- 2024
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In: Environmental Pollution. - : Springer. - 0269-7491 .- 1873-6424.
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Journal article (peer-reviewed)abstract
- Calcium oxide (CaO), utilized in semi-dry/dry desulfurization systems at municipal solid waste incineration (MSWI) plants, demonstrates some capability to remove polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study assessed the gas-phase PCDD/F removal performance of CaO, activated carbon (AC) and CaO-AC mixtures. Alone, CaO achieved removal efficiencies of only 31.9% for mass and 50.8% for I-TEQ concentration. However, CaO-AC mixtures exhibited significantly higher efficiencies, reaching 96.0% and 92.5% for mass and I-TEQ concentrations, respectively, surpassing those of AC alone, which were 74.7% and 58.5%. BET analysis indicated that CaO's limited surface area and pore structure are major constraints on its adsorption performance. Density functional theory (DFT) calculations revealed that the π-π electron donor-acceptor (EDA) interaction enhances the adsorption between AC and PCDD/F, with adsorption energies ranging from -1.02 to -1.24 eV. Additionally, the induced dipole interactions between CaO and PCDD/F contribute to adsorption energies ranging from -1.13 to -1.43 eV. Moreover, with increasing chlorination levels, PCDD/F molecules are more predisposed to accept electron transfers from the surfaces of AC or CaO, thereby facilitating adsorption. The calculation for mixed AC and CaO showed that CaO modifies AC's properties, enhancing its ability to adsorb gas phase PCDD/Fs, with the higher adsorption energy and more electrons transfer, aligning with gas phase PCDD/Fs adsorption experiments. This study provides a comprehensive understanding of how CaO influences the PCDD/F adsorption performance of AC.
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4. |
- Wang, Renjun, et al.
(author)
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Sympathoexcitation in Rats With Chronic Heart Failure Depends on Homeobox D10 and MicroRNA-7b Inhibiting GABBR1 Translation in Paraventricular Nucleus
- 2016
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In: Circulation Heart Failure. - 1941-3289 .- 1941-3297. ; 9:1
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Journal article (peer-reviewed)abstract
- BACKGROUND: Chronic heart failure (CHF) increases sympathoexcitation through angiotensin II (ANG II) receptors (AT1R) in the paraventricular nucleus (PVN). Recent publications indicate both γ-aminobutyric acid B-type receptor 1 (GABBR1) and microRNA-7b (miR-7b) are expressed in the PVN. We hypothesized that ANG II regulates sympathoexcitation through homeobox D10 (HoxD10), which regulates miR-7b in other tissues.METHODS AND RESULTS: Ligation of the left anterior descendent coronary artery in rats caused CHF and sympathoexcitation. PVN expression of AT1R, HoxD10, and miR-7b was increased, whereas GABBR1 was lower in CHF. Infusion of miR-7b in the PVN caused sympathoexcitation in control animals and enhanced the changes in CHF. Antisense miR-7b infused in PVN normalized GABBR1 expression while attenuating CHF symptoms, including sympathoexcitation. A luciferase reporter assay detected miR-7b binding to the 3' untranslated region of GABBR1 that was absent after targeted mutagenesis. ANG II induced HoxD10 and miR-7b in NG108 cells, effects blocked by AT1R blocker losartan and by HoxD10 silencing. miR-7b transfection into NG108 cells decreased GABBR1 expression, which was inhibited by miR-7b antisense. In vivo PVN knockdown of AT1R attenuated the symptoms of CHF, whereas HoxD10 overexpression exaggerated them. Finally, in vivo PVN ANG II infusion caused dose-dependent sympathoexcitation that was abrogated by miR-7b antisense and exaggerated by GABBR1 silencing.CONCLUSIONS: There is an ANG II/AT1R/HoxD10/miR-7b/GABBR1 pathway in the PVN that contributes to sympathoexcitation and deterioration of cardiac function in CHF.
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5. |
- Xing, Xu, et al.
(author)
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Double bismuth-based Bi2S3/Bi2MoO6 S-scheme heterojunction for ultrafast photocatalytic removal of Cr(VI)
- 2024
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In: Journal of Environmental Chemical Engineering. - 2213-3437. ; 12:2
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Journal article (peer-reviewed)abstract
- The mild, fast and green removal of hexavalent chromium (Cr(VI)) from wastewater has already attracted extensive attention due to the severe acute toxicity and carcinogenicity of Cr(VI). At present work, Bi2S3/Bi2MoO6 S-scheme heterojunctions were constructed by facile solvothermal assembly and in situ anion exchange methods for visible light-driven efficient photocatalytic removal of Cr(VI). The structure-activity relationship, photoelectrochemical properties, and density functional theory (DFT) calculations revealed that the controllable construction of the heterostructure significantly expanded the light response range and remarkably enhanced the light absorption capacity. In particular, the unique charge transfer mechanism of this S-scheme heterojunction is conducive to promoting efficient separation of photogenerated charges and thus enhancing the photocatalytic performance. The results show that the total efficiency of Cr(VI) removal by the developed Bi2S3/Bi2MoO6 heterojunction under visible light irradiation is 98.5% within 6 min, with a k value of 0.466 min−1. This work provides a new route with enormous promise to construct bismuth-based S-scheme heterojunction photocatalysts for clean and efficient environmental remediation.
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6. |
- Zhang, Qian, et al.
(author)
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A quantitative assessment of the distribution and extent of urban clusters in China
- 2012
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In: Journal of Geographical Sciences. - : Springer Science and Business Media LLC. - 1009-637X .- 1861-9568. ; 22:1, s. 137-151
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Journal article (peer-reviewed)abstract
- Urban clusters are the expected products of high levels of industry and urbanization in a country, as well as being the basic units of participation in global competition. With respect to China, urban clusters are regarded as the dominant formation for boosting the Chinese urbanization process. However, to date, there is no coincident, efficient, and credible methodological system and set of techniques to identify Chinese urban clusters. This research investigates the potential of a computerized identification method supported by geographic information techniques to provide a better understanding of the distribution of Chinese urban clusters. The identification method is executed based on a geographic information database, a digital elevation model, and socio-economic data with the aid of ArcInfo Macro Language programming. In the method, preliminary boundaries are identified according to transportation accessibility, and final identifications are achieved from limiting city numbers, population, and GDP in a region with the aid of the rasterized socio-economic dataset. The results show that the method identifies nine Chinese urban clusters, i.e., Pearl River Delta, Lower Yangtze River Valley, Beijing-Tianjin-Hebei Region, Northeast China Plain, Middle Yangtze River Valley, Central China Plains, Western Taiwan Strait, Guanzhong and Chengdu-Chongqing urban clusters. This research represents the first study involving the computerized identification of Chinese urban clusters. Moreover, compared to other related studies, the study's approach, which combines transportation accessibility and socio-economic characteristics, is shown to be a distinct, effective and reliable way of identifying urban clusters.
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