•TOC, TN, TP, TS, and δ13C in the Chaihe Reservoir sediment, a plateau lake in China, were studied.•The sedimentary records of TOC, TN, TP, TS imply trends in eutrophication.•C/S, C/P, and N/P ratios ...can reflect evolution of trophic conditions in water body.•Endogenous and exogenous inputs were sources of organic matter in the sediment.•The eutrophic process was associated with socioeconomic development and natural changes.
In order to reveal eutrophication evolution, radionuclides (210Pb and 137Cs), total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), total sulphur (TS) concentrations, stable carbon isotope (δ13C) were analyzed in a sediment core collected from Chaihe Reservoir in Kunming, Yunnan province, southwest China during 2019. The results showed that the 210Pbex activities ranged from 9.67 to 130.72 Bq/Kg (average 61.84 Bq/Kg), and the age sequence ranged from 1885 to 2018. The sediment accumulation rates were in the range of 0.04–1.85 cm/yr, with an average of 0.56 cm/yr and exogenous inputs have been increasing. Based on the nutrients (C, N, P, and S), the aquatic environment in the reservoir experienced a shift from near-natural status to human interference status. In particular, human activities has increased the input of C, N, and S into the aquatic environment in the recent years. Elemental ratios reflected that aquatic environment in the reservoir was obviously restricted by N. Additionally, oxygen concentration decreased in the sediment, corresponding to the aggravated eutrophication in the reservoir. The algae, CAM plants, and bunchless fibrous plants inputs primarily accounted for the sources of organic matter in the sediment. Ecological risk assessment showed that eutrophic ecological risk caused N in the sediment has continuously increased, whereas eutrophic ecological risk caused P has been decreased in recent years. These findings implied that eutrophication in the reservoir has been aggravated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the last few decades, the eutrophication of lakes has been a serious issue in the middle and lower reaches of the Yangtze River watershed. To explore the relationship between lake systems and ...anthropogenic activities, sediments were collected from the Shuanglong reservoir in the Dianchi watershed in Southwest China. Total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), and the carbon isotopic ratio (
δ
13
C) were analyzed in sediment cores to reconstruct the effects of natural succession and human activities on the past lacustrine environmental conditions. A reliable chronology of the sediment core was established by using the
210
Pb dating technique, which indicated that the age span of the 70-cm sediment core is from the years 1871 to 2011. Above – 31 cm depth in the core, TN, TP, TOC, C/N, and
δ
13
C increased significantly, indicating that eutrophication has occurred since the 1980s. By combining the indicators of
δ
13
C and C/N, it was shown that terrestrial and lacustrine components were the main sources of organic matter (OM) in the reservoir, which was mostly controlled by terrestrial C
3
plants and algae. Since the 1980s, increased sewage discharge, fish aquaculture, fertilizer application, population, and economic strength have sped up the eutrophication process, and the eutrophication was further intensified in 2001.
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CEKLJ, 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
In this study, the concentrations of seven heavy metals (Cr, Ni, Cu, Zn, As, Hg, and Pb) and Pb isotope in a sediment core from the Shuanglong reservoir, Southwestern China, were investigated. Based ...on the constant rate of supply (CRS) model, the age span of a 60 cm sediment sample was determined to range from the years 1944 to 2015. Combined with chronology and heavy metal content, the evolution of the sources and pollution levels of heavy metals showed a changing trend composed of various stages. The sources of heavy metals transitioned from natural origins in 1944–1964 to industrial origins in 1965–2004. The subsequent reduction in heavy metal content was mainly due to the vigorous implementation of environmental protection policies from 2005 to 2012. In recent years (2013–2015), the heavy metal content has increased due to frequent human activity. Principal component analysis (PCA), correlation analysis, and the coefficient of variation (CV) analysis indicated that Cr, Ni, Cu, Zn, and As were derived from natural processes, Pb mainly came from automobile manufacturing, and Hg was mainly from industrial sources. The values of the geo-accumulation index (Ig), single pollution index (Pi), and single potential ecological risk index (Er) showed that the contamination of Hg and Pb was slight to moderate. Moreover, the values of the potential ecological risk index (RI), pollution load index (PLI), and Nemerow index (PN) indicated that the Shuanglong reservoir is under low ecological risk.
Soil erosion and nutrient loss are important environmental and ecological problems in the Dianchi watershed in southwestern China. Woodlands—the primary land type in the Dianchi watershed—play an ...important ecological role in controlling soil and water loss. In this study, we compared soil erosion and loss of total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) in woodlands of different ages, i.e., young forest, medium forest, and near-mature forest, at the Dongda River catchment in south-western Dianchi watershed. Furthermore, changes in stoichiometries in soil were analyzed. The average degree of erosion of each forest age stage was below moderate. Based on the non-arable soil erosion modulus models of
137
Cs and
210
Pb
ex
, the soil erosion rates decreased gradually with the increasing forest age. The forest age affected soil nutrient distribution and loss. The losses of TOC and TP gradually decreased, while the losses of TN first increased and then decreased with the growth of forest age. TOC, TN, and TP were enriched in the topsoil. Forest age affected soil stoichiometry and soil nutrient supply level. In general, the forest can effectively reduce soil erosion and nutrient loss in the red soil area with the forest age increasing.
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CEKLJ, 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
Lake sediment records the evolution process of the interaction between human and nature. It is important to master the lacustrine sedimentation rate for the ecological environment assessment of ...catchment. A 60-cm sediment core was collected in the Da River Reservoir during 2019 to analyze radionuclides (
210
Pb and
137
Cs) massic activities, grain size, total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and metals (Mn, Cu, Al, and Pb) mass fractions to reconstruct the response of sedimentation rate to environmental evolution. The environmental changes in the small catchment were classified into the following three stages through cluster analysis (CA) for geochemical parameters in the sediment core: phase I (1881–1985), phase II (1987–1999), and phase III (2000–2018). The average depth sedimentation rates (ADSRs) of the three stages were 0.33, 0.90, and 1.50 cm/year, respectively. The sedimentation rates increased from the bottom to the surface layer, indicating that the exogenous inputs into the reservoir have been occurring. The sediment deposition in phase III was strongly disturbed by the environmental changes (such as warmer climate and intensified land use). Therefore, sedimentation rates showed a rapid increase. Both Pearson correlation analysis and redundancy analysis (RDA) showed that sedimentation rates were positively correlated with climatic factors, particle size, nutrients and metals mass fractions, elemental ratios, and socioeconomic parameters. Sedimentation rates show high sensitivity to anthropogenic activities and climatic change, which can be used to reconstruct the environmental evolution process at a small catchment scale.
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CEKLJ, 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
In this study, the concentrations of seven heavy metals (Cr, Ni, Cu, Zn, As, Hg, and Pb) and Pb isotope in a sediment core from the Shuanglong reservoir, Southwestern China, were investigated. Based ...on the constant rate of supply (CRS) model, the age span of a 60 cm sediment sample was determined to range from the years 1944 to 2015. Combined with chronology and heavy metal content, the evolution of the sources and pollution levels of heavy metals showed a changing trend composed of various stages. The sources of heavy metals transitioned from natural origins in 1944-1964 to industrial origins in 1965-2004. The subsequent reduction in heavy metal content was mainly due to the vigorous implementation of environmental protection policies from 2005 to 2012. In recent years (2013-2015), the heavy metal content has increased due to frequent human activity. Principal component analysis (PC A), correlation analysis, and the coefficient of variation (CV) analysis indicated that Cr, Ni, Cu, Zn, and As were derived from natural processes, Pb mainly came from automobile manufacturing, and Hg was mainly from industrial sources. The values of the geo-accumulation index (Ig), single pollution index (Pi), and single potential ecological risk index (Er) showed that the contamination of Hg and Pb was slight to moderate. Moreover, the values of the potential ecological risk index (RI), pollution load index (PIT), and Nemerow index (P^) indicated that the Shuanglong reservoir is under low ecological risk. Keywords: typical water-supply reservoir; heavy metals; sediment sources; pollution evaluation
Herein, we report a pH stimulus-disaggregated BODIPY sensitizer (PTS) with low background-toxicity for achieving activated photodynamic/photothermal tumor therapy. Both the photodynamic and ...photothermal properties of PTS can be activated under acidic conditions, and PTS exhibits excellent antitumor properties, which is revealed by both
in vitro
and
in vivo
tests.
A pH activated photodynamic/photothermal sensitizer applicable to tumor ablation.
Visual sorting of express packages is faced with many problems such as the various types, complex status, and the changeable detection environment, resulting in low sorting efficiency. In order to ...improve the sorting efficiency of packages under complex logistics sorting, a multi-dimensional fusion method (MDFM) for visual sorting in actual complex scenes is proposed. In MDFM, the Mask R-CNN is designed and applied to detect and recognize different kinds of express packages in complex scenes. Combined with the boundary information of 2D instance segmentation from Mask R-CNN, the 3D point cloud data of grasping surface is accurately filtered and fitted to determining the optimal grasping position and sorting vector. The images of box, bag, and envelope, which are the most common types of express packages in logistics transportation, are collected and the dataset is made. The experiments with Mask R-CNN and robot sorting were carried out. The results show that Mask R-CNN achieves better results in object detection and instance segmentation on the express packages, and the robot sorting success rate by the MDFM reaches 97.2%, improving 2.9, 7.5, and 8.0 percentage points, respectively, compared to baseline methods. The MDFM is suitable for complex and diverse actual logistics sorting scenes, and improves the efficiency of logistics sorting, which has great application value.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Depression is a common mental disease, with some patients exhibiting ideas and behaviors such as self-harm and suicide. The drugs currently used to treat depression have not achieved good results. It ...has been reported that metabolites produced by intestinal microbiota affect the development of depression. In this study, core targets and core compounds were screened by specific algorithms in the database, and three-dimensional structures of these compounds and proteins were simulated by molecular docking and molecular dynamics software to further study the influence of intestinal microbiota metabolites on the pathogenesis of depression. By analyzing the RMSD gyration radius and RMSF, it was finally determined that NR1H4 had the best binding effect with genistein. Finally, according to Lipinski's five rules, equol, genistein, quercetin and glycocholic acid were identified as effective drugs for the treatment of depression. In conclusion, the intestinal microbiota can affect the development of depression through the metabolites equol, genistein and quercetin, which act on the critical targets of DPP4, CYP3A4, EP300, MGAM and NR1H4.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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