Subcellular distributions and chemical forms of cadmium （Cd） in the leaves, stems and roots were investigated in low-Cd accumulation cultivars and high-Cd accumulation cultivars ofpakchoi （Brassica chinensis L.）. ...Subcellular distributions and chemical forms of cadmium （Cd） in the leaves, stems and roots were investigated in low-Cd accumulation cultivars and high-Cd accumulation cultivars ofpakchoi （Brassica chinensis L.）. Root cell wall played a key role in limiting soil Cd from entering the protoplast, especially in the low-Cd cultivars. The high-Cd cultivars had significantly higher leaf and stem Cd concentrations than the low-Cd cultivars in cell wall fraction, chloroplast/trophoplast fraction, organelle fraction and soluble fraction. In low-Cd cultivars, which were more sensitive and thus had greater physiological needs of Cd detoxification than high-Cd cultivars, leaf vacuole sequestrated higher proportions of Cd. Cd in the form of pectate/protein complexes （extracted by 1 tool. L~ NaC1） played a decisive role in Cd translocation from root to shoot, which might be one of the mechanisms that led to the differences in shoot Cd accumulation between the two types of cultivars. Furthermore, the formation of Cd- phosphate complexes （extracted by 2% HAc） was also involved in Cd detoxification within the roots of pakchoi under high Cd stress, suggesting that the mechanisms of Cd detoxification might be different between low- and high-Cd cultivars.展开更多
As one of the major concerns of climate change,identifying a proper eco‐friendly insulation gas for replacing sulphur hexafluoride(SF_(6))becomes a prominent research topic in recent years.c-C_(4)F_(8),CF_(3)I,C_(5)F...As one of the major concerns of climate change,identifying a proper eco‐friendly insulation gas for replacing sulphur hexafluoride(SF_(6))becomes a prominent research topic in recent years.c-C_(4)F_(8),CF_(3)I,C_(5)F_(10O),C_(6)F_(12O)and C4F7N are some potential al-ternatives that are proved to have excellent characteristics,including high insulation strengths and low Global Warming Potentials(GWPs).Beyond these key factors,the decomposition products of these alternatives are closely related to the gases'insulation performance,as well as the safety of operators and the compatibility with other materials.In addition,the type and content of decomposition products can be used for fault diagnosis.Therefore,a number of studies were carried out to reveal the decomposition mechanism of these alternative gases,and then to explore the gases'application feasibility and strategy.The recent advances obtained in these studies,including theoretical calcu-lation methods,detection of gas decomposition products,decomposition mechanism are reviewed,and some perspectives for future works are proposed.It is concluded that the phenomenon of solid matter precipitation in c-C_(4)F_(8)and CF_(3)I gas decomposition cannot be ignored and that more research is needed to reveal the influence of buffer gases,micro‐aerobic,micro‐water and other impurities on the gas decomposition process.展开更多
A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed ...A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.展开更多
Majority of type 2 diabetes mellitus(T2DM)patients are highly susceptible to several forms of cognitive impairments,particularly dementia.However,the underlying neural mechanism of these cognitive impairments remains ...Majority of type 2 diabetes mellitus(T2DM)patients are highly susceptible to several forms of cognitive impairments,particularly dementia.However,the underlying neural mechanism of these cognitive impairments remains unclear.We aimed to investigate the correlation between whole brain resting state functional connections(RSFCs)and the cognitive status in 95 patients with T2DM.We constructed an elastic net model to estimate the Montreal Cognitive Assessment(MoCA)scores,which served as an index of the cognitive status of the patients,and to select the RSFCs for further prediction.Subsequently,we utilized a machine learning technique to evaluate the discriminative ability of the connectivity pattern associated with the selected RSFCs.The estimated and chronological MoCA scores were significantly correlated with R=0.81 and the mean absolute error(MAE)=1.20.Additionally,cognitive impairments of patients with T2DM can be identified using the RSFC pattern with classification accuracy of 90.54%and the area under the receiver operating characteristic(ROC)curve(AUC)of 0.9737.This connectivity pattern not only included the connections between regions within the default mode network(DMN),but also the functional connectivity between the task-positive networks and the DMN,as well as those within the task-positive networks.The results suggest that an RSFC pattern could be regarded as a potential biomarker to identify the cognitive status of patients with T2DM.展开更多
文摘Subcellular distributions and chemical forms of cadmium （Cd） in the leaves, stems and roots were investigated in low-Cd accumulation cultivars and high-Cd accumulation cultivars ofpakchoi （Brassica chinensis L.）. Root cell wall played a key role in limiting soil Cd from entering the protoplast, especially in the low-Cd cultivars. The high-Cd cultivars had significantly higher leaf and stem Cd concentrations than the low-Cd cultivars in cell wall fraction, chloroplast/trophoplast fraction, organelle fraction and soluble fraction. In low-Cd cultivars, which were more sensitive and thus had greater physiological needs of Cd detoxification than high-Cd cultivars, leaf vacuole sequestrated higher proportions of Cd. Cd in the form of pectate/protein complexes （extracted by 1 tool. L~ NaC1） played a decisive role in Cd translocation from root to shoot, which might be one of the mechanisms that led to the differences in shoot Cd accumulation between the two types of cultivars. Furthermore, the formation of Cd- phosphate complexes （extracted by 2% HAc） was also involved in Cd detoxification within the roots of pakchoi under high Cd stress, suggesting that the mechanisms of Cd detoxification might be different between low- and high-Cd cultivars.
基金supported by the National Key R&D Pro-gramme under Grant No.2017YFB0902500the Tech-nology Programme of State Grid Corporation of China under Grant No.5500-202,055,292A-0-0-00.
文摘As one of the major concerns of climate change,identifying a proper eco‐friendly insulation gas for replacing sulphur hexafluoride(SF_(6))becomes a prominent research topic in recent years.c-C_(4)F_(8),CF_(3)I,C_(5)F_(10O),C_(6)F_(12O)and C4F7N are some potential al-ternatives that are proved to have excellent characteristics,including high insulation strengths and low Global Warming Potentials(GWPs).Beyond these key factors,the decomposition products of these alternatives are closely related to the gases'insulation performance,as well as the safety of operators and the compatibility with other materials.In addition,the type and content of decomposition products can be used for fault diagnosis.Therefore,a number of studies were carried out to reveal the decomposition mechanism of these alternative gases,and then to explore the gases'application feasibility and strategy.The recent advances obtained in these studies,including theoretical calcu-lation methods,detection of gas decomposition products,decomposition mechanism are reviewed,and some perspectives for future works are proposed.It is concluded that the phenomenon of solid matter precipitation in c-C_(4)F_(8)and CF_(3)I gas decomposition cannot be ignored and that more research is needed to reveal the influence of buffer gases,micro‐aerobic,micro‐water and other impurities on the gas decomposition process.
基金This work was supported by the National Natural Science Foundation of China （Grant No. 20877104） the Key Research Project of Guangdong Province （No. 2009B030802006）+1 种基金 and the National Science and Technology Key Project for Water Protection, China （Grant No. 2009ZX07211-002-3） The authors are indebted to Kaylin Huang from USA and Roy Luo from MTC Industries, Inc., Edgewood, NY, USA for helpful comments in the preparation of this manuscript.
文摘A pot experiment was carried out by growing 29 different genotypes （Amaranthus spp.） of vegetable amaranth under low- （0.12 mg. kg-1） and middle- （0.40 mg · kg-1） cadmium （Cd） exposure. The result showed that amaranth was vulnerable to cadmium （Cd） contamination in soil. Variations of Cd concentrations in both roots and edible parts among genotypes were significant （P 〈 0.001） in both treatments. Cd concentrations in edible parts of the tested genotypes grown under low- and middle-Cd levels were significantly correlated （p 〈 0.01）, implying that Cd- accumulating property of amaranth is genotype-dependent. Differences in Cd chemical forms between cv. Nanxing- dayemashixian （cv. Nan）, a selected typical pollution-safe cultivar （Cd-PSC）, and cv. Pennongjianyexian （cv. Pen）, a selected typical non-Cd-PSC, under different Cd exposure conditions were compared. It was found that the alternation of Cd in FNaC1 （Cd form extracted by 1 mol.L-1NaC1） may be a key factor in regulating Cd accumulation of different amaranth genotypes and that the protein-binding Cd is considered to be associated with Cd translocation. The results indicated that amaranth is capable of enduring high level of Cd pollution when grown as vegetable crop, and accordingly, consuming vegetable amaranth would bring high health risk. Therefore, adopting Cd-PSC strategy would help reducing the risk of Cd pollution in amaranth. In this study, cv. Nan was identified as a Cd-PSC and recommended to be applied production practice.
基金supported by the National Natural Science Foundation of China(Grant Nos.81772012,81227901,61673051,81641168,31470047,81271565,81527805,and61231004)the National Key R&D Program of China(Grant No.2017YFA0205200)the Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.2019136)
文摘Majority of type 2 diabetes mellitus(T2DM)patients are highly susceptible to several forms of cognitive impairments,particularly dementia.However,the underlying neural mechanism of these cognitive impairments remains unclear.We aimed to investigate the correlation between whole brain resting state functional connections(RSFCs)and the cognitive status in 95 patients with T2DM.We constructed an elastic net model to estimate the Montreal Cognitive Assessment(MoCA)scores,which served as an index of the cognitive status of the patients,and to select the RSFCs for further prediction.Subsequently,we utilized a machine learning technique to evaluate the discriminative ability of the connectivity pattern associated with the selected RSFCs.The estimated and chronological MoCA scores were significantly correlated with R=0.81 and the mean absolute error(MAE)=1.20.Additionally,cognitive impairments of patients with T2DM can be identified using the RSFC pattern with classification accuracy of 90.54%and the area under the receiver operating characteristic(ROC)curve(AUC)of 0.9737.This connectivity pattern not only included the connections between regions within the default mode network(DMN),but also the functional connectivity between the task-positive networks and the DMN,as well as those within the task-positive networks.The results suggest that an RSFC pattern could be regarded as a potential biomarker to identify the cognitive status of patients with T2DM.
