•Certain characteristics of nonpoint source pollution research were visualized by Citespace during 2001–2015.•The research attention on nonpoint source pollution was not evenly distributed around the ...world.•Nonpoint source pollution research includes control measures, modeling, pollutants, research regions and technologies.•The future researches on nonpoint source pollution will likely focus on SWAT application, GIS and ecological measures.
The purpose of this paper is to make insights into certain characteristics of nonpoint source pollution research, and consequently to show the global trends as well as assist researchers to establish future research directions. Based on the SCI-E and SSCI databases, 3246 journal articles on nonpoint source pollution were retrieved from 2001 to 2015. Nonpoint source pollution research maintained steady growth in the past 15 years. Among all countries, USA was the most active contributor with the most publications and cooperation. As for institutions, Chinese Academy of Sciences ranked first with 143 articles, and USDA-ARS in USA played a key role for intimate collaboration with other institutions. And most articles were recorded by Environmental Sciences & Ecology, Environmental Sciences and Water Resources. Further, Journal of Environmental Quality and Water Research were the most productive and influential journals, respectively. Based on keyword co-word and reference co-citation analysis by Citespace, nonpoint source pollution research includes multiple areas (control measures, modeling, pollutants, research regions and technologies). And future researches on nonpoint source pollution will likely focus on SWAT application, GIS and ecological measures.
Air pollution presents one of most significant environmental issues in China, especially in the Beijing-Tianjin-Hebei (Jing-Jin-Ji) urban agglomeration. With the release of “The Outline of ...Coordinated Development for Beijing-Tianjin-Hebei region”, air quality in the Jing-Jin-Ji urban agglomeration has drawn wide concern. This study aims to provide a better understanding of inter-regional and sectoral linkages of air pollutants emissions and to identify key sectors that contribute to the transfer of embodied emissions in Beijing-Tianjin-Hebei region of China. A modified inter-regional and sectoral model was developed in this study for embodied emission flows based on the Multi-region input-output table. According to this model, transfer patterns of embodied air pollutant emissions (SO2, Soot, Dust and NOx) flows in Jing-Jin-Ji urban agglomeration were analyzed. Similarly, the driving forces of the flows were examined. Results show that the transfer pattern of the most significant NTE flow was the same for SO2 (18.8 kt), Soot (26.3 kt), Dust (12.8 kt) and NOx (29.9 kt), i.e. from the Nonmetal Products sector of Hebei province to the Construction sector of Beijing. This flow accounted for 35.7%, 45.5%, 36.7%, 42.0% of the total embodied emissions of SO2, Soot, Dust, NOx from Hebei province to Beijing respectively. Similarly, this study revealed that the contribution of Scale effect, Intensity effect and Structure effect was about 40%, 40% and 20% for the NTE from Hebei province to Beijing, respectively. Policy interventions were proposed accordingly.
CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) are competitive emitting materials for illumination and display because of their outstanding photophysical properties. However, the conventional synthetic ...approaches suffer from low yields, complex procedures, and toxic chemicals. In this work, we demonstrate a one-step microwave-assisted approach to prepare CsPbX3 NCs. The homogeneous heating and rapid temperature increment of microwave preparation facilitate the growth of CsPbX3 NCs, producing the NCs with high photoluminescence quantum yields up to 90%, narrow emission full-width at half-maximum, and emission color tunable from blue to red. By optimizing the preparation conditions of the microwave-assisted approach, CsPbX3 NCs with cation- and halide anion-controlled emission properties, tunable reaction rate, and enhanced stability are prepared. Light-emitting diode (LED) prototypes are further fabricated by employing the as-prepared CsPbX3 NCs as the color conversion materials on commercially available 365 nm GaN LED chips.
Aggregation/assembly induced emission (AIE) has been observed for metal nanoclusters (NCs), but the origin of the enhanced emission is not fully understood, yet. In this work, the significant ...contribution of metal defects on AIE is revealed by engineering the self-assembly process of Cu NCs using ethanol. The presence of ethanol leads to a rapid assembly of NCs into ultrathin nanosheets, promoting the formation of metal defects-rich surface. Detailed studies and computer simulation confirm that the metal defects-rich nanosheets possess increased Cu(I)-to-Cu(0) ratio, which greatly influences ligand-to-metal–metal charge transfer and therewith facilitates the radiative relaxation of excitons. Consequently, the Cu NCs self-assembly nanosheets exhibit obvious emission enhancement.
Organic nanoparticles (NPs) from donor–acceptor based coumarin derivatives, 6-4-(N,N-diphenylamino)phenyl-3-ethoxycarbonyl coumarin (DPA-CM), with an average size of 5.82 nm, were synthesized by a ...facile reprecipitation method using water as a poor solvent and tetrahydrofuran as a good solvent. Red-shifted absorption, blue-shifted photoluminescence emission, and aggregation-induced enhanced electrochemiluminescence (ECL) emission were observed for the DPA-CM NPs in aqueous solution compared with the original DPA-CM in organic solution. The aggregation-induced enhanced ECL emission is ascribed to the combined effects of the small size of the DPA-CM NPs, the restricted conformational relaxation in the NPs, and the good stability of the cationic radical of DPA-CM. A strong and stable ECL emission is obtained at the DPA-CM NPs modified glassy carbon electrode in the presence of tri-n-propylamine, and the ECL intensity of the DPA-CM NPs modified electrode is quenched linearly in the range of 0.05–50 μM with detection limit of 0.04, 0.2, and 0.4 μM for ascorbic acid, uric acid, and dopamine, respectively. This work shows an example of donor–acceptor based organic NPs as ECL emitters and their analytical applications to monitor biomolecules.
Purpose: To study whether radiation-induced bleeding in the bone marrow induced iron accumulation, and subsequently caused ferroptosis in granulocyte-macrophage hematopoietic progenitor cells.
...Materials and methods: Male mice were subjected to different doses (0, 4, 8, or 10 Gy) of gamma radiation from a
137
Cs source. The changes in iron metabolism or ferroptosis-related parameters of irradiated bone marrow were accessed with biochemical, histopathological, and antibody methods. Hematocytes were detected with a hematology analyzer. The counts of granulocyte-macrophage hematopoietic progenitor cells were measured with the granulocyte-macrophage colony-forming unit.
Results: Iron accumulation occurred in the bone marrow, which caused by radiation-induced hemorrhage. The iron accumulation triggered an iron regulatory protein-ferroportin 1 axis to increase serum iron levels. Using LDN193189, radiation-induced iron accumulation was demonstrated to decrease white blood cell counts at least partly through a decrease in the counts of granulocyte-macrophage hematopoietic progenitor cells. The reduction in the counts of granulocyte-macrophage hematopoietic progenitor cells was subsequently demonstrated to attribute to ferroptosis with the use of ferroptosis inhibitors and through the detection of ferroptosis related-parameters. The survival rate of irradiated mice was improved using Ferrostatin-1 or LDN193189.
Conclusions: These findings suggest that radiation-induced hemorrhage in the bone marrow causes ferroptosis in granulocyte-macrophage hematopoietic progenitor cells, and anti-ferroptosis has the potential to be a radioprotective strategy to ameliorate radiation-induced hematopoietic injury.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this study, the function of a non-ribosomal peptide synthetase-like (NRPS-like) encoding gene
(
) was investigated to reveal the association between NRPS and nematocidal activity in the ...nematode-trapping fungus
. Sequence analysis indicated that the encoded product of
is an adenylation domain of non-ribosomal peptide synthetases and extended short-chain dehydrogenase/reductase domain-containing proteins, and displays a wide substrate spectrum. The Δ
mutants were more sensitive to chemical stressors than the wild type. Disruption of
impeded the nematocidal efficiency of
. Metabolomics analysis showed that secondary metabolite biosynthesis and lipid metabolism were altered in the mutants. The phenotypic changes in the mutants can be attributed to the down-regulation of various metabolites, including fatty acyls, prenol lipids, steroidsand steroid derivative, and amino acid derivatives, identified in the present study. This study investigated the association between the non-ribosomal polypeptide-encoding gene
and nematicidal activity in
, providing a reference for resolving the predation mechanism of nematode-trapping fungus.
While teaching the histories of the Ming and Qing dynasties, Meng Sen (1869-1937), developed three textbooks in the 1930s: Lecture Notes on the Ming History (明史讲义 Mingshi jiangyi), Lecture Notes on ...the Qing History (清史讲义 Qingshi jiangyi), and Lecture Notes on the History of the Founding of the Manchu State (满洲开国史讲义 Manzhou kaiguo shi jiangyi). In these book titles, the term "history" refers specifically to "standard history." In tracing Meng Sen's original intention in producing these textbooks, all three works suggest the author's desire to write history. He wrote Lecture Notes on the Ming History to prepare a future revision of the History of the Ming (明史 Mingshi); similarly he wrote Lecture Notes on the Qing History and Lecture Notes on the History of the Founding of the Manchu State with the intention to revise the Draft History of the Qing (清史稿 Qingshi gao). Meng Sen summarized Sima Guang's (司马光, 1019-86) view of history as "imitating the good and avoiding the bad," which he believed represented the "essential meaning of history." Meng followed Sima Guang's model in compiling the Lecture Notes on the Ming History and Lecture Notes on the Qing History, as shown in their style and format. By comparison, his writing of the Lecture Notes on the History of the Founding of the Manchu State attempted to merge the traditional annals-biographic style with narrative history from the West, or to pour old wine into a new bottle. Meng Sen presented his innovative efforts at Peking University, introducing young scholars to standards for history writing, and doing his utmost to guide and encourage his students; some of whom became noted scholars in the study of Ming and Qing histories.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
DNA damage could lead to the accumulation of cytosolic DNA, and the cytosolic DNA-sensing pathway has been implicated in multiple inflammatory diseases. However, the role of cytosolic DNA-sensing ...pathway in asthma pathogenesis is still unclear. This article explored the role of airway epithelial cyclic GMP-AMP synthase (cGAS), the major sensor of cytosolic dsDNA, in asthma pathogenesis. Cytosolic dsDNA accumulation in airway epithelial cells (ECs) was detected in the setting of allergic inflammation both in vitro and in vivo. Mice with cGAS deletion in airway ECs were used for OVA- or house dust mite (HDM)-induced allergic airway inflammation. Additionally, the effects of cGAS knockdown on IL-33-induced GM-CSF production and the mechanisms by which IL-33 induced cytosolic dsDNA accumulation in human bronchial epithelial (HBE) cells were explored. Increased accumulation of cytosolic dsDNA was observed in airway epithelium of OVA- or HDM-challenged mice and in HBE cells treated with IL-33. Deletion of cGAS in the airway ECs of mice significantly attenuated the allergic airway inflammation induced by OVA or HDM. Mechanistically, cGAS participates in promoting T
2 immunity likely via regulating the production of airway epithelial GM-CSF. Furthermore, Mito-TEMPO could reduce IL-33-induced cytoplasmic dsDNA accumulation in HBE cells possibly through suppressing the release of mitochondrial DNA into the cytosol. In conclusion, airway epithelial cGAS plays an important role via sensing the cytosolic dsDNA in asthma pathogenesis and could serve as a promising therapeutic target against allergic airway inflammation.
Circadian rhythm refers to the inherent 24-h cycle oscillation of biochemical, physiological and behavioral functions, which is almost universal in eukaryotes. At least 14 core clock genes have been ...reported to form multiple chain feedback loops that confer intrinsic circadian rhythmicity onto the molecular clock. Accumulating evidence has shown that the circadian gene dysfunction resulted from single nucleotide polymorphisms (SNPs), deletions, epigenetic modification, and deregulation is strongly associated with cancer risk. In the present review, we describe the composition of circadian rhythm system. We highlight the function and mechanism of clock genes in cancer pathogenesis and progression. Moreover, their potential clinical implications as prognostic biomarkers and therapeutic targets have been addressed.
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