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1.
Environ Pollut ; 318: 120899, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36565910

ABSTRACT

This study explored the temporospatial distribution, gas-particle partition, and pollution sources of atmospheric speciated mercury (ASM) from the eastern offshore waters of the Taiwan Island (TI) to the northern South China Sea (SCS). Both gaseous and particulate mercury were simultaneously sampled at three remote sites in four seasons. The average concentrations of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particulate bound mercury (PBM) were 2.05 ± 0.45 ng/m3, 19.17 ± 5.39 pg/m3, and 0.11 ± 0.06 ng/m3, respectively. The concentrations of GEM and PBM in the cold seasons were higher than those in the warm seasons, but those of GOM had an opposite trend. In terms of gas-solid partition, ASM was apportioned as 91.3-97.3% of GEM and 2.7-8.7% of GOM and PBM. The average concentrations of GEM, GOM, and PBM at the Green Island (GI) were 2.21 ± 0.47 ng/m3, 22.31 ± 5.35 pg/m3, and 0.12 ± 0.06 ng/m3; those at the Kenting Peninsula (KT) were 2.11 ± 0.43 ng/m3, 20.57 ± 4.38 pg/m3, and 0.11 ± 0.06 ng/m3; and those at the Dongsha Islands (DS) were 1.84 ± 0.40 ng/m3, 15.19 ± 3.58 pg/m3, and 0.08 ± 0.05 ng/m3, respectively. Overall, the spatial distribution of ASM concentrations showed the order as: GI > KT > DS. Air masses blown mainly from the West Pacific Ocean (WPO) and SCS in summer showed the lowest ASM concentrations. Oppositely, high ASM concentrations were commonly observed in spring and winter when polluted air masses were blown by Asian Northeastern Monsoons (ANMs). The transport routes of polluted air masses were originated mainly from North China, Central China, Northeast China, Korea and Japan, and mostly passed through the urban and industrial regions in the northeastern Asian countries.


Subject(s)
Air Pollutants , Mercury , Air Pollutants/analysis , Taiwan , Mercury/analysis , Environmental Monitoring , China , Seasons , Gases/analysis
2.
Sci Total Environ ; 815: 152785, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-34990687

ABSTRACT

In this study, the pollution characteristics, spatiotemporal variation, and potential sources of atmospheric speciated mercury (ASM) in an industrial harbor area were explored. Gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particle-bound mercury (PBM) were sampled by a self-designed manual system at three harbor sites in four seasons. The yearly average concentrations of GEM, GOM, and PBM were 6.7 ± 2.0 ng/m3, 244 ± 70 pg/m3, and 410 ± 105 pg/m3, respectively. The seasonal average ASM concentration was in the order of: winter > fall > spring > summer. In terms of species, GEM dominated ASM, while reactive mercury (RM = GOM + PBM) accounted for 6.0-15.7%of ASM, implying that ASM was governed by anthropogenic sources in the harbor area. The highest ASM concentrations were observed at Site Zhonghe (ZH), which is mainly influenced by both ship exhausts and industrial emissions, and positively correlated with CO, NOx, and SO2. In particular, GOM was positively correlated with O3, and negatively correlated with air temperature and relative humidity, showing high impact from atmospheric photochemical reactions. Air masses transporting westerly in spring were mainly from ship exhausts. In summer, air masses transporting from the south were from utility power plants and machinery exhausts. In fall and winter, air masses were transported mainly from the north, blowing by the long-range transport of polluted air masses originated from the north. Both principal component analysis and positive matrix factorization results indicate that coal burning, industrial emissions, and vehicular exhausts are the main contributors to ASM. Site Zhongdao (ZD) was close to the bulk carrier loading and unloading zones and was highly influenced by mobile sources, while Site ZH was mainly influenced by the neighboring industrial complex.


Subject(s)
Air Pollutants , Mercury , Air Pollutants/analysis , Atmosphere , Environmental Monitoring , Asia, Eastern , Mercury/analysis , Seasons
3.
Plant Signal Behav ; 16(12): 1997513, 2021 12 02.
Article in English | MEDLINE | ID: mdl-34763610

ABSTRACT

The ionotropic glutamate receptor (iGluR) plays an important role in neuronal signaling in animal cells. There are at least 20 glutamate receptor-like (GLR) genes in Arabidopsis thaliana. These genes are involved in seed germination, root growth, wounding response, stomata closure, etc. A recent study showed that Arabidopsis clade III glutamate receptor GLR3.7 is involved in salt stress response. We tested whether GLR3.7 is involved in abscisic acid (ABA) response. In the present study, we found that the expression of GLR3.7 was reduced by ABA treatment. Under ABA-treated condition, GLR3.7 overexpression lines exhibited significantly higher seed germination rate at 60, 72 and 84 h under ABA-treated condition. A point mutation in 14-3-3 binding site of GLR3.7 in GLR3.7-S860A overexpression lines exhibited higher seed germination inhibition under ABA-treated conditions. Our results support that GLR3.7 is involved in ABA response in Arabidopsis. In addition, Ser-860 of GLR3.7 appears to be important in ABA response.


Subject(s)
Abscisic Acid , Arabidopsis Proteins , Arabidopsis , Receptors, Glutamate , Abscisic Acid/metabolism , Abscisic Acid/pharmacology , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant/genetics , Germination/genetics , Mutation , Receptors, Glutamate/genetics , Receptors, Glutamate/metabolism , Seeds/metabolism
4.
Hu Li Za Zhi ; 68(3): 73-80, 2021 Jun.
Article in Chinese | MEDLINE | ID: mdl-34013508

ABSTRACT

BACKGROUND & PROBLEM: The need to use an indwelling nasogastric tube, urinary catheter, or tracheostomy tube (the so-called "three tubes") because of illness or prolonged bedrest is increasing. The functions and effectiveness of these tubes may be maintained only with correct care. Improper care, slippage, obstruction, or infection may in severe cases cause septic shock or even death. PURPOSE: To increase the completeness of the reverse demonstration of three tubes care instructions by primary caregivers to further improve related care quality. RESOLUTION: Between February 10th and March 31st, 2019, the completeness rates of reverse demonstration of nasogastric tube, urinary catheter, and tracheostomy tube care instructions among the primary caregivers participating in this study were shown to be low, at 42.5%, 38%, and 58.3%, respectively. The plausible causes were: 1. Human: Poor communication, forgetting the care steps, having no time for learning, and fear of performing nasogastric tube rotation; 2. Instrument: Lack of graphic demonstrations in health education materials; 3. Policy: Lack of standards and auditing. The implemented intervention involved creating innovative health-education instruments, videos and flash cards about three tubes care in multiple languages, and straps for holding the urinary catheter and developing standards and an auditing system for the reverse demonstration of three tube care instructions by primary caregivers. RESULTS: The completeness rates for the reverse demonstration of nasogastric tube, urinary catheter, and tracheostomy tube care instructions among the primary caregivers improved to 97.3%, 96.3%, and 95%, respectively. CONCLUSIONS: Using the innovative health-education aids and improvements introduced in this study, the ability of primary caregivers to correctly perform the care steps should improve significantly.


Subject(s)
Caregivers , Intubation, Gastrointestinal , Health Education , Humans , Quality of Health Care , Tracheostomy
5.
Sci Rep ; 11(1): 5678, 2021 03 11.
Article in English | MEDLINE | ID: mdl-33707484

ABSTRACT

This study explored the temporal variation, gas-particle partition, and potential origins of atmospheric speciated mercury at a remote island in the South China Sea. Two-year data of three mercury species was measured at the Taiping Island. Air masses were clustered into five transport routes (A-E) to resolve the potential origins of atmospheric mercury. Field measurement showed that the concentration of gaseous elemental mercury (GEM) (1.33 ± 0.52 ng/m3) was close to the GEM background level of Northern Hemisphere, while those of GOM and PHg were 13.39 ± 3.58 and 94.33 ± 30.25 pg/m3, respectively. Both regular and intensive samplings concluded a consistent trend of higher mercury level in winter and spring than that in summer and fall. GEM dominated atmospheric mercury in all seasons (86.2-98.5%), while the highest partition of particle-bound mercury (PHg) was observed in winter (13.8%). The highest GEM concentrations were observed for Route A originating from central China and western Taiwan Island, and followed by Routes D and E from the Philippines, Malaysia, and Indonesia, while the lowest concentrations of GEM were observed for Routes B and C originating from North China, Korea, and Japan. Most importantly, high correlation of GEM versus levoglucosan and K+ in PM2.5 (r = 0.764 and 0.758, p < 0.01) confirmed that GEM was mainly emitted from biomass burning sources at the surrounding countries.

6.
Front Plant Sci ; 10: 1169, 2019.
Article in English | MEDLINE | ID: mdl-31632419

ABSTRACT

Ionotropic glutamate receptors (iGluRs) are ligand-gated cation channels that mediate fast excitatory neurotransmission in the mammalian central nervous system. In the model plant Arabidopsis thaliana, a family of 20 glutamate receptor-like proteins (GLRs) shares similarities to animal iGluRs in sequence and predicted secondary structure. However, the function of GLRs in plants is little known. In the present study, a serine site (Ser-860) of AtGLR3.7 phosphorylated by a calcium-dependent protein kinase (CDPK) was identified and confirmed by an in vitro kinase assay. Using a bimolecular fluorescence complementation and quartz crystal microbalance analyses, the physical interaction between AtGLR3.7 and the 14-3-3ω protein was confirmed. The mutation of Ser-860 to alanine abolished this interaction, indicating that Ser-860 is the 14-3-3ω binding site of AtGLR3.7. Compared with wild type, seed germination of the glr3.7-2 mutant was more sensitive to salt stress. However, the primary root growth of GLR3.7-S860A overexpression lines was less sensitive to salt stress than that of the wild-type line. In addition, the increase of cytosolic calcium ion concentration by salt stress was significantly lower in the glr3.7-2 mutant line than in the wild-type line. Moreover, association of 14-3-3 proteins to microsomal fractions was less in GLR3.7-S860A overexpression lines than in GLR3.7 overexpression line under 150 mM NaCl salt stress condition. Overall, our results indicated that GLR3.7 is involved in salt stress response in A. thaliana by affecting calcium signaling.

7.
Nanoscale ; 7(44): 18663-70, 2015 Nov 28.
Article in English | MEDLINE | ID: mdl-26498343

ABSTRACT

The in-plane (kip) and through-plane (ktp) thermal conductivities of heat sinks using carbon nanotubes (CNTs), graphene nanosheets (GNs), and CNT/GN composites are extracted from two experimental setups within the 323-373 K temperature range. Hierarchical three-dimensional CNT/GN frameworks display higher kip and ktp values, as compared to the CNT- and GN-based heat sinks. The kip and ktp values of the CNT/GN-based heat sink reach as high as 1991 and 76 W m(-1) K(-1) at 323 K, respectively. This improved thermal conductivity is attributed to the fact that the hierarchical heat sink offers a stereo thermal conductive network that combines point, line, and plane contact, leading to better heat transport. Furthermore, the compression treatment provided an efficient route to increase both kip and ktp values. This result reveals that the hierarchical carbon structures become denser, inducing more thermal conductive area and less thermal resistivity, i.e., a reduced possibility of phonon-boundary scattering. The correlation between thermal and electrical conductivity (ε) can be well described by two empirical equations: kip = 567 ln(ε) + 1120 and ktp = 20.6 ln(ε) + 36.1. The experimental results are obtained within the temperature range of 323-373 K, suitably complementing the thermal management of chips for consumer electronics.

8.
Chem Commun (Camb) ; 50(76): 11165-8, 2014 Oct 04.
Article in English | MEDLINE | ID: mdl-25111534

ABSTRACT

The combinational modification of the morphology, alloying, and support for Pt catalysts has been optimized towards the oxygen reduction reaction. Graphene-supported PtPd nanorods have lower unfilled Pt d-states than carbon-supported Pt nanoparticles (Pt/C) and their specific and mass activities after the accelerated durability test are about 6.5 and 2.7 times higher than those of Pt/C, attributed to the synergistic electronic modification effect and graphene-metal interaction.

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