Purpose
Variations in hydrocarbon composition and concentration are essential for the assessment of its source and environmental health in estuarine environments. This study aims to reveal the ...spatial and temporal distribution of multiple hydrocarbons in surface sediments of the Pearl River Estuary, and to further determine various sources of these hydrocarbons.
Materials and methods
Surface sediments were taken monthly from four sites along a spatial transect from the Pearl River Estuary in a whole year by using a gravitational bottom sampler. A series of bulk parameters including the grain size, total organic carbon content, and total nitrogen content were measured. Hydrocarbons in sediments were extracted and analyzed by the gas chromatography-mass spectrometry.
Results and discussion
The abundances of higher plants and phytoplankton-derived
n
-alkanes, petrogenically derived pristane, phytane, hopanes, and steranes with geological configuration, and anthropogenically derived hydrocarbons, including linear alkylbenzenes and polycyclic aromatic hydrocarbons all showed decreasing trends towards the coastal ocean. In contrast, the diatom-derived
C
25
highly branched isoprenoids increased towards saline sites. Monthly fluctuations of aliphatic and aromatic hydrocarbons at the estuarine mouth were smaller than the upstream freshwater sites, where high monthly variation (up to fivefold) was observed for most of the hydrocarbons detected.
Conclusions
This study showed substantial monthly and spatial variations of hydrocarbons in the surface sediments of the Pearl River Estuary. Distribution and composition of sedimentary hydrocarbons indicate mainly anthropogenic inputs (e.g., petroleum residues and synthetic detergents) and terrestrially higher plants, followed by aquatic inputs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Enhancing the output performance of triboelectric nanogenerators (TENGs) is essential for increasing their application in smart devices. Oxygen-vacancy-rich BiO
nanosheets (BiO
NSs) are ...advanced-engineered nanomaterials with excellent piezoelectric properties. Herein, a stretchable unsymmetrical BiO
NSs deposited-hydrogel made of polyacrylamide (PAM) as a multimodal TENG is rationally fabricated, and the performance of TENG can be tailored by controlling the BiO
NSs deposition amount and spatial distribution. The alteration of resistance caused by the Poisson effect of PAM/BiO
composite hydrogel (H-BiO
) can be used as a piezoresistive sensor, and the piezoelectricity of BiO
NSs can effectively enhance the density of transfer charge, thus improving the output performance of the H-BiO
-based TENG. In addition, the chemical cross-linking between the BiO
NSs and the PAM polymer chain allows the hydrogel electrode to have a higher tensile capacity (867%). Used for biomechanical motion signal detection, the sensors made of H-BiO
have high sensitivity (gauge factor = 6.93) and can discriminate a range of forces (0.1-5.0 N) at low frequencies (0.5-2.0 Hz). Finally, the prepared TENG can collect biological energy and convert it into electricity. Consequently, the improved TENG shows a good application prospect as multimodal biomechanical sensors by combining piezoresistive, piezoelectric, and triboelectric effects.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Enhancing the output performance of triboelectric nanogenerators (TENGs) is essential for increasing their application in smart devices. Oxygen-vacancy-rich BiO2-x nanosheets (BiO2-x NSs) are ...advanced-engineered nanomaterials with excellent piezoelectric properties. Herein, a stretchable unsymmetrical BiO2-x NSs deposited-hydrogel made of polyacrylamide (PAM) as a multimodal TENG is rationally fabricated, and the performance of TENG can be tailored by controlling the BiO2-x NSs deposition amount and spatial distribution. The alteration of resistance caused by the Poisson effect of PAM/BiO2-x composite hydrogel (H-BiO2-x) can be used as a piezoresistive sensor, and the piezoelectricity of BiO2-x NSs can effectively enhance the density of transfer charge, thus improving the output performance of the H-BiO2-x-based TENG. In addition, the chemical cross-linking between the BiO2-x NSs and the PAM polymer chain allows the hydrogel electrode to have a higher tensile capacity (867%). Used for biomechanical motion signal detection, the sensors made of H-BiO2-x have high sensitivity (gauge factor = 6.93) and can discriminate a range of forces (0.1-5.0 N) at low frequencies (0.5-2.0 Hz). Finally, the prepared TENG can collect biological energy and convert it into electricity. Consequently, the improved TENG shows a good application prospect as multimodal biomechanical sensors by combining piezoresistive, piezoelectric, and triboelectric effects.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Although mutations of several genes are associated with arrhythmogenic right ventricular cardiomyopathy (ARVC), the exact correlation between genotype and ventricular arrhythmia features remains ...unclear. This study was aimed to examine the possible association of the 9 known genes of ARVC with clinical and electrophysiological characteristics.
Ninety subjects diagnosed with ARVC who underwent electrophysiological study were recruited for screening the 9 known ARVC-causing genes. A total of 53 mutations were identified in 57 (63%) subjects. Mutation carriers had more frequent clinical ventricular tachycardia (VT; 89% versus 55%; P<0.001) and negative T waves in V1 to V3 (61% versus 33%; P=0.016). Subjects with plakophilin-2 (PKP2) mutations also had more frequent VT than those without mutations in PKP2. Comparison between subjects with multiple and single mutations showed that syncope occurred more often in the former group (58% versus 24%; P=0.018). VT was significantly more often induced in mutation carriers compared with noncarriers (75% versus 39%; P=0.001), as well as in PKP2 mutation carriers compared with subjects without PKP2 mutations (80% versus 48%; P=0.002). Induced VT with a rate ≥ 200 bpm was more often documented in mutation carriers (88% versus 54%; P=0.013), as well as in PKP2 mutation carriers (91% versus 67%; P=0.041).
Pathogenic gene mutations were found in nearly two thirds of subjects diagnosed with ARVC. Mutation carriers, especially PKP2, had a higher proportion of a history of VT and more inducible fast VT.
•Effects of Ga addition on structure and magnetic properties of SmCo7 alloy were studied.•A stable TbCu7-type single phase can be obtained in as-cast SmCo6.1Ga0.9 alloys.•Ga addition affects the ...stability, order degree and nucleation of 1:7H phase.•TbCu7-type phase in the ribbons is basically stable below 500°C.•The phase transition of ribbons during the heating process was discussed.
In this article, the effects of Ga addition on the structure and magnetic properties of SmCo7 alloy were studied. The results show that a stable TbCu7-type single phase can be obtained in as-cast SmCo7−xGax alloys when a proper amount of Ga is introduced (x=0.9). Meanwhile, all SmCo7−xGax ribbons melt-spun at 40m/s are composed of single TbCu7-type phase. So both the appropriate doping of Ga, and more especially the rapid cooling rate, can effectively stabilize the TbCu7-type structure. Moreover, Ga addition affects not only the stability and the order degree of 1:7H phase but also the uniformity of nucleation. Magnetic tests reveal that the coercivity, remanence and remanence ratio of the ribbons increase with the Ga addition, and reach their maximum values (7117.0±2081.5 Oe, 36.7±4.2emu/g and 0.771±0.037, respectively) when x=0.9. At the same time, the maximum magnetization of ribbons and Curie temperature (Tc) of Sm–Co phases tend to decrease with the amount of Ga. In particular, the TbCu7-type phase in SmCo7−xGax ribbons is basically stable below 500°C, and the phase transition during the heating process is also discussed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We generated complete mitochondrial genome sequences data for 4 genera (Onchidium, Platevindex, Paraoncidium and Peronia) in Onchidiidae to construct a phylogenetic tree in conjunction with other 9 ...existing data among gastropods. The topology showed that the taxa clustered into two main groups of four species, one of which included Onchidium struma and the Platevindex mortoni, the other Paraoncidium reevesii and Peronia verruculata. The process in Pulmonata from sea to land in accordance with the evolution of respiratory organs from branchial gills to pulmonary cavity has been shown. This will also constitute a framework for phylogeny evolution analysis, systematic classfication of Onchidiidae and other euthyneurans (pulmonates and opisthobranchs).
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
In this work, SmCo(7), SmCo(7)(CNTs)(0.05), SmCo(6.1)Si(0.9), SmCo(5.1)Si(0.9)(CNTs)(0.05) as-cast ingots and ribbons were prepared by arc-melting and melt-spinning methods respectively. The effects ...of Si and/or CNTs additions on the structure and magnetic properties of SmCo(7)-based alloys were investigated. It was found that adding Si into the SmCo(7)-based as-cast alloys can stabilize the TbCu(7)-type structure, while CNTs addition facilitates the formation of Th(2)Zn(17)-type phase. However, for SmCo(7)-based ribbons, the cooling rate plays a more significant role in the formation of a single TbCu7-type phase than the doped elements. The coercivity (H(c)) and remanence ratio (M(r)/M(2T)) of all SmCo(7)-based ribbons increase with the addition of CNTs and/or Si. In particular, simultaneous addition of CNTs and Si can improve the H(c) and M(r)/M(2T) more effectively than that of a single one. On the other hand, the magnetization of SmCo(7)-based ribbons at high temperature is improved by CNTs addition while decreased by Si addition. At the same time, the thermal stability of ribbons decreases when Si is introduced. The possible mechanism of magnetization reversal in the SmCo(7)-based ribbons containing Si and/or CNTs is considered to be the combination of nucleation and pinning.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A multiproxy approach including bulk organic carbon, δ13C, lignin phenols, and lipid biomarker analyses were applied to characterize the source and composition of sedimentary organic matter in the ...head part of Three Gorges Reservoir. OM consisted of both natural (autochthonous and allochthonous) and anthropogenic inputs. The natural OM included input from vascular plants, especially non-woody angiosperms. The allochthonous input included plankton and microbial production, likely due to localized eutrophication. Anthropogenic inputs likely derived from petroleum input and/or urban activities. Other anthropogenic inputs were untreated sewage waste. These influences were concluded to be regionally specific point sources of pollution based on relative distributions and on the fact that molecular characteristics of sedimentary OM were not distributed smoothly along a gradient.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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