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1.
Environ Sci Technol ; 58(36): 16131-16141, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39190601

ABSTRACT

Liquid crystal monomers (LCMs) are emerging organic pollutants due to their potential persistence, toxicity, and bioaccumulation. This study first characterized the levels and compositions of 19 LCMs in organisms in the Pearl River Estuary (PRE), estimated their bioaccumulation and trophic transfer potential, and identified priority contaminants. LCMs were generally accumulated in organisms from sediment, and the LCM concentrations in all organisms ranged from 32.35 to 1367 ng/g lipid weight. The main LCMs in organisms were biphenyls and analogues (BAs) (76.6%), followed by cyanobiphenyls and analogues (CBAs) (15.1%), and the least were fluorinated biphenyls and analogues (FBAs) (11.2%). The most abundant LCM monomers of BAs, FBAs, and CBAs in LCMs in organisms were 1-(4-propylcyclohexyl)-4-vinylcyclohexane (15.1%), 1-ethoxy-2,3-difluoro-4-(4-(4-propylcyclohexyl) cyclohexyl) benzene (EDPBB, 10.1%), and 4'-propoxy-4-biphenylcarbonitrile (5.1%), respectively. The niche studies indicated that the PRE food web was composed of terrestrial-based diet and marine food chains. Most LCMs exhibited biodilution in the terrestrial-based diet and marine food chains, except for EDPBB and 4,4'-bis(4-propylcyclohexyl) biphenyl (BPCHB). The hydrophobicity, position of fluorine substitution of LCMs, and biological habits may be important factors affecting the bioaccumulation and trophic transfer of LCMs. BPCHB, 1-(prop-1-enyl)-4-(4-propylcyclohexyl) cyclohexane, and EDPBB were characterized as priority contaminants. This study first reports the trophic transfer processes and mechanisms of LCMs and the biomonitoring in PRE.


Subject(s)
Environmental Monitoring , Estuaries , Rivers , Water Pollutants, Chemical , Rivers/chemistry , Food Chain , Liquid Crystals , Animals
2.
Bioresour Technol ; 408: 131221, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39111396

ABSTRACT

Food waste (FW) and its biogas residue were considered as sources of terrestrial microplastics (MPs) and phthalic acid esters (PAEs) contamination. However, there was a lack of research and understanding of the MPs and PAEs pollution problem in FW dry anaerobic digestion process (DADP). The MPs and PAEs in three stages of the DADP with the largest monomer disposal scale in China were identified. At the biogas residue extrusion stage, MPs abundance and PAEs concentration reached the highest values, which were 3.63 ± 0.45 × 103 N·kg-1 and 3.62 ± 0.72 mg·kg-1, respectively. Furthermore, there was a significant positive correlation between MPs and PAEs throughout the process (p < 0.05). Although bacteria and fungi with plastic degradation potential were present in all stages, the contamination problem of MPs and PAEs cannot be completely solved through DADP. This study provides a scientific basis for preventing and controlling the pollution of MPs and PAEs.


Subject(s)
Biodegradation, Environmental , Esters , Food Loss and Waste , Microplastics , Phthalic Acids , Anaerobiosis , Bacteria/metabolism , Esters/metabolism , Fungi/metabolism , Phthalic Acids/metabolism , Refuse Disposal/methods
3.
Sci Total Environ ; 946: 174204, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-38914342

ABSTRACT

Film mulching has been extensively used to improve agricultural production in arid regions of China. However, without sufficient mulch film recovery, large amounts of residual film accumulated in the farmland, which would affect crop yield and water use efficiency (WUE). In order to comprehensively analyze the effects of residual film on crop yield and WUE, and clarify its influencing mechanism, present study adopted a meta-analysis to systematically evaluate the impacts of residual film on soil physicochemical properties, crop root growth, yield, and WUE. The results showed that residual film significantly increased soil bulk density and the soil moisture content in 0-20 cm soil layer, but decreased soil porosity, soil organic matter, soil total nitrogen content, and soil moisture content in >20 cm soil layer, especially when residual film amount was >400 kg ha-1. Residual film significantly reduced crop root dry weight, root length, root diameter, root volume and root surface area. Generally, crop yield and WUE decreased with the increase of residual film amount; and crop yield was reduced by about 14.00 % when the residual film amount increased by 1000 kg ha-1. In average, crop yield and WUE under film residual condition were significantly decreased by 13.46 % and 9.21 %, respectively. The negative effects of residual film on root growth, yield and WUE were greater for cash crops (cotton, tomato and potato) than for cereal crops (wheat, maize). The structural equation model indicated that residual film generated indirect negative effects on crop yield and WUE by directly affecting soil physicochemical properties and crop root growth, with the standard path coefficients of -0.302 and - 0.217, respectively. The results would provide a theoretical basis for reducing residual film pollution on farmland and promoting the green and sustainable development of agriculture.


Subject(s)
Agriculture , Crops, Agricultural , Plant Roots , Plastics , Soil , Soil/chemistry , Crops, Agricultural/growth & development , Plant Roots/growth & development , China , Agriculture/methods , Water , Crop Production/methods
4.
Int J Biol Macromol ; 274(Pt 1): 132645, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38917581

ABSTRACT

Renewable natural fibers (e.g., cellulose nanocrystals (CNCs)) are being applied for reinforcing bio-based polylactic acid (PLA). For improvement in the interfacial compatibility between CNCs and PLA and the dispersibility of CNCs, a quaternary ammonium salt-coated CNCs (Q-CNCs) hybrid was prepared in this study based on an esterification self-polymerization method, and such hybrid was further utilized as a new strengthening/toughening nanofiller for producing the Q-CNCs-reinforced PLA composite. The results confirmed that quaternary ammonium salt coatings could efficiently enhance CNCs/PLA interfacial compatibility via mechanical interlocking and semi-interpenetrating networks. Attributing to the synergistic effect of quaternary ammonium salts and CNCs, a considerable enhancement in processing, mechanical, and thermal properties was gained in the obtained Q-CNCs-reinforced PLA composite. With the addition of 0.5 wt% Q-CNCs, the tensile strength, Young's modulus, and elongation at break of the Q-CNCs-reinforced PLA composite was raised by approximately 23 %, 37 % and 18 %, respectively; compared with pure PLA, the obtained composite had excellent bacteriostatic properties and good transparency. This work discusses the development of high-performance, low-cost and sustainable PLA-based composites on a potential application in packaging materials.


Subject(s)
Anti-Bacterial Agents , Cellulose , Nanoparticles , Polyesters , Quaternary Ammonium Compounds , Polyesters/chemistry , Cellulose/chemistry , Nanoparticles/chemistry , Quaternary Ammonium Compounds/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Tensile Strength , Nanocomposites/chemistry
5.
Environ Toxicol Chem ; 43(7): 1557-1568, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38695729

ABSTRACT

Persistent organic pollutants pose a great threat to amphibian populations, but information on the bioaccumulation of contaminants in amphibians remains scarce. To examine the tissue distribution and maternal transfer of organic halogenated pollutants (OHPs) in frogs, seven types of tissues from black-spotted frog (muscle, liver, kidney, stomach, intestine, heart, and egg) were collected from an e-waste-polluted area in South China. Among the seven frog tissues, median total OHP concentrations of 2.3 to 9.7 µg/g lipid weight were found (in 31 polychlorinated biphenyl [PCB] individuals and 15 polybrominated diphenyl ether [PBDE], dechlorane plus [syn-DP and anti-DP], bexabromobenzene [HBB], polybrominated biphenyl] PBB153 and -209], and decabromodiphenyl ethane [DBDPE] individuals). Sex-specific differences in contaminant concentration and compound compositions were observed among the frog tissues, and eggs had a significantly higher contaminant burden on the whole body of female frogs. In addition, a significant sex difference in the concentration ratios of other tissues to the liver was observed in most tissues except for muscle. These results suggest that egg production may involve the mobilization of other maternal tissues besides muscle, which resulted in the sex-specific distribution. Different parental tissues had similar maternal transfer mechanisms; factors other than lipophilicity (e.g., molecular size and proteinophilic characteristics) could influence the maternal transfer of OHPs in frogs. Environ Toxicol Chem 2024;43:1557-1568. © 2024 SETAC.


Subject(s)
Persistent Organic Pollutants , Animals , Female , Tissue Distribution , Male , Persistent Organic Pollutants/metabolism , Environmental Monitoring , Halogenated Diphenyl Ethers/metabolism , Anura/metabolism , China , Ranidae/metabolism , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/analysis
6.
Environ Sci Pollut Res Int ; 31(27): 39271-39284, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38814555

ABSTRACT

To enhance the real-time monitoring and early-warning capabilities for dust disasters in underground coal mine, this paper presents a novel WGAN-CNN-based prediction approach to predict the dust concentration at underground coal mine working faces. Dust concentration, wind speed, temperature, and methane concentration were collected as the original data due to their nonlinear relationship. The consistency between the generated and original data distributions was verified through PCA dimensionality reduction analysis. The predictive performance of this approach was assessed using five metrics (R2, EVS, MSE, RMSE, and MAE) and compared with three other algorithms (Random Forest Regressor, MLP Regressor, and LinearSVR). The findings indicate that a majority of the generated data falls within the distribution range of the real dataset, exhibiting reduced levels of volatility and dispersion. The R2 values of prediction results are all above 98%, and the MSE values are between 0.0007 and 0.0106. The proposed approach exhibits superior predictive accuracy and robust model generalization capabilities compared to alternative algorithms, thereby enhancing the real-time monitoring and early-warning level of dust disasters in underground coal mine. This will facilitate the realization of advanced prevention and control measures for dust disasters, showcasing a wide range of potential applications.


Subject(s)
Coal Mining , Dust , Dust/analysis , Coal , Environmental Monitoring/methods , Algorithms , Neural Networks, Computer
7.
Sensors (Basel) ; 24(4)2024 Feb 11.
Article in English | MEDLINE | ID: mdl-38400341

ABSTRACT

Orbit angular momentum (OAM) has been considered a new dimension for improving channel capacity in recent years. In this paper, a millimeter-wave broadband multi-mode waveguide traveling-wave antenna with OAM is proposed by innovatively utilizing the transmitted electromagnetic waves (EMWs) characteristic of substrate-integrated gap waveguides (SIGWs) to introduce phase delay, resulting in coupling to the radiate units with a phase jump. Nine "L"-shaped slot radiate elements are cut in a circular order at a certain angle on the SIGW to generate spin angular momentum (SAM) and OAM. To generate more OAM modes and match the antenna, four "Π"-shaped slot radiate units with a 90° relationship to each other are designed in this circular array. The simulation results show that the antenna operates at 28 GHz, with a -10 dB fractional bandwidth (FBW) = 35.7%, ranging from 25.50 to 35.85 GHz and a VSWR ≤ 1.5 dB from 28.60 to 32.0 GHz and 28.60 to 32.0 GHz. The antenna radiates a linear polarization (LP) mode with a gain of 9.3 dBi at 34.0~37.2 GHz, a l = 2 SAM-OAM (i.e., circular polarization OAM (CP-OAM)) mode with 8.04 dBi at 25.90~28.08 GHz, a l = 1 and l = 2 hybrid OAM mode with 5.7 dBi at 28.08~29.67 GHz, a SAM (i.e., left/right hand circular polarization (L/RHCP) mode with 4.6 dBi at 29.67~30.41 GHz, and a LP mode at 30.41~35.85 GHz. In addition, the waveguide transmits energy with a bandwidth ranging from 26.10 to 38.46 GHz. Within the in-band, only a quasi-TEM mode is transmitted with an energy transmission loss |S21| ≤ 2 dB.

8.
Chemosphere ; 352: 141386, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38316276

ABSTRACT

The growing number of infections caused by drug-resistant bacteria which arise from the overuse of antibiotics has severely affected the normal operation of human society. The high antibacterial activity of QAS makes it promising as an alternative to antibiotics, but it suffers from secondary pollution due to its non-degradation. Here we have synthesized a class of gemini quaternary ammonium salts (GQAS) with different carbon chain lengths containing ester groups by using facile methylation reaction. Quaternary ammonium groups contribute to insert negatively charged bacterial membranes, resulting in membrane damage and bacteria death. Compared with conventional single-chain QAS, except for the more efficient antibacterial efficiency attribute to the presence of the second carbon chain, GQAS with alterable antibacterial properties can minimize the possibility of bacterial resistance and reduce the accumulation of GQAS in the environment through the introduction of degradable ester groups. GQAS is completely superior to the commercial bactericide benzalkonium chloride (BAC) in both antibacterial activity and degrade performance, which can be used as a more environmentally friendly bactericide.


Subject(s)
Ammonium Compounds , Water Purification , Humans , Salts/pharmacology , Quaternary Ammonium Compounds/pharmacology , Anti-Bacterial Agents/pharmacology , Bacteria , Sterilization , Carbon , Esters
9.
Article in English | MEDLINE | ID: mdl-38083452

ABSTRACT

Body channel communication (BCC) which uses the human body as the communication channel has shown better energy efficiency and security compared with air channel communication. This article presents a simple, stable, and high transfer rate BCC technique using Manchester encoding, capacitive termination, and digital signal transfer operation. Manchester encoding is used to realize the spectrum migration of the baseband signal, and digital signal transmission simplifies system design and improves signal stability. The chip is fabricated in 65-nm technology. The experimental results show that the proposed transceiver achieved the highest data rates of 60 Mbps and the measured RX sensitivity is -64dBm. And the chip is also used to set up a multi-sensor nodes communication system to realize the data interaction between one hub and eight slave sensors utilizing the human body as the communication medium.


Subject(s)
Telemetry , Wearable Electronic Devices , Humans , Equipment Design , Telemetry/methods , Wireless Technology , Communication
10.
Protein Pept Lett ; 30(12): 1020-1029, 2023.
Article in English | MEDLINE | ID: mdl-38031269

ABSTRACT

BACKGROUND: Revealing the process and mechanism of colorectal cancer will facilitate the discovery of new biomarkers and contribute to the development of targeted drugs. OBJECTIVES: This study aimed to explore the potentially functional circRNA-miRNA-mRNA network in colorectal cancer (CRC), and further explore its mechanism. METHODS: Bioinformatics analysis was used to identify the differentially expressed circRNAs and mRNAs. Gene set enrichment analysis and KEGG pathways analysis were used to screen out the differentially expressed genes and observe crucial pathways that might have a strong association with CRC. Then, a network targeting circRNA, miRNA, and mRNA has been built by using the Cytoscape software. In addition, the expression of circRNA_0001573, miR-382-5p, and FZD3 was detected by qRT-PCR in CRC tissues and cells (SW480, HCT116, and HT29). RESULTS: Abnormal expressions of circRNAs and mRNAs were obtained by bioinformatics analysis and visualized by Volcano plot and Heatmap. A series of highly correlated pathways were enriched by KEGG analysis. The interaction network of circRNA_0001573/miR-382-5p/FZD3 axis was predicted. The expressions of circRNA_0001573 and FZD3 were highly upregulated and the miR- 382-5p expression level was decreased in CRC tissues and cell lines (SW480, HCT116, and HT29). CONCLUSION: Our study suggests that circRNA_0001573 and circRNA_0001573/miR-382-5p/FZD3 regulatory networks might provide a potential diagnosis for colorectal cancer.


Subject(s)
Colorectal Neoplasms , MicroRNAs , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Biomarkers/metabolism , Colorectal Neoplasms/genetics
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