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1.
Animals (Basel) ; 13(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38067039

RESUMEN

Sheep aggression detection is crucial for maintaining the welfare of a large-scale sheep breeding environment. Currently, animal aggression is predominantly detected using image and video detection methods. However, there is a lack of lightweight network models available for detecting aggressive behavior among groups of sheep. Therefore, this paper proposes a model for image detection of aggression behavior in group sheep. The proposed model utilizes the GhostNet network as its feature extraction network, incorporating the PWConv and Channel Shuffle operations into the GhostConv module. These additional modules improve the exchange of information between different feature maps. An ablation experiment was conducted to compare the detection effectiveness of the two modules in different positions. For increasing the amount of information in feature maps of the GhostBottleneck module, we applied the Inverted-GhostBottleneck module, which introduces inverted residual structure based on GhostBottleneck. The improved GhostNet lightweight feature extraction network achieves 94.7% Precision and 90.7% Recall, and its model size is only 62.7% of YOLOv5. Our improved model surpasses the original model in performance. Furthermore, it addresses the limitation of the video detection model, which was unable to accurately locate aggressive sheep. In real-time, our improved model successfully detects aggressive behavior among group sheep.

2.
Animals (Basel) ; 13(16)2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37627427

RESUMEN

In order to solve the problems of low efficiency and subjectivity of manual observation in the process of group-sheep-aggression detection, we propose a video streaming-based model for detecting aggressive behavior in group sheep. In the experiment, we collected videos of the sheep's daily routine and videos of the aggressive behavior of sheep in the sheep pen. Using the open-source software LabelImg, we labeled the data with bounding boxes. Firstly, the YOLOv5 detects all sheep in each frame of the video and outputs the coordinates information. Secondly, we sort the sheep's coordinates using a sheep tracking heuristic proposed in this paper. Finally, the sorted data are fed into an LSTM framework to predict the occurrence of aggression. To optimize the model's parameters, we analyze the confidence, batch size and skipping frame. The best-performing model from our experiments has 93.38% Precision and 91.86% Recall. Additionally, we compare our video streaming-based model with image-based models for detecting aggression in group sheep. In sheep aggression, the video stream detection model can solve the false detection phenomenon caused by head impact feature occlusion of aggressive sheep in the image detection model.

3.
Animals (Basel) ; 13(3)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36766301

RESUMEN

There are some problems with estrus detection in ewes in large-scale meat sheep farming: mainly, the manual detection method is labor-intensive and the contact sensor detection method causes stress reactions in ewes. To solve the abovementioned problems, we proposed a multi-objective detection layer neural network-based method for ewe estrus crawling behavior recognition. The approach we proposed has four main parts. Firstly, to address the problem of mismatch between our constructed ewe estrus dataset and the YOLO v3 anchor box size, we propose to obtain a new anchor box size by clustering the ewe estrus dataset using the K-means++ algorithm. Secondly, to address the problem of low model recognition precision caused by small imaging of distant ewes in the dataset, we added a 104 × 104 target detection layer, making the total target detection layer reach four layers, strengthening the model's ability to learn shallow information and improving the model's ability to detect small targets. Then, we added residual units to the residual structure of the model, so that the deep feature information of the model is not easily lost and further fused with the shallow feature information to speed up the training of the model. Finally, we maintain the aspect ratio of the images in the data-loading module of the model to reduce the distortion of the image information and increase the precision of the model. The experimental results show that our proposed model has 98.56% recognition precision, while recall was 98.04%, F1 value was 98%, mAP was 99.78%, FPS was 41 f/s, and model size was 276 M, which can meet the accurate and real-time recognition of ewe estrus behavior in large-scale meat sheep farming.

4.
Chemosphere ; 302: 134887, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35551941

RESUMEN

Knowledge of the mobility of tetracycline (TC) antibiotics in porous media is critical to understand their potential environmental influences. The transport characteristics of TC in sand columns with three different surfactants, including Tween 80, sodium dodecylbenzene sulfonate (SDBS), and didodecyldimethylammonium bromide (DDAB) under various conditions were investigated in this study. Results demonstrated that all surfactants enhanced TC transport under neutral conditions (10 mM NaCl at pH 7.0). The observation was attributed mostly to deposition site competition, higher electrostatic repulsion between TC molecules and sand grains, steric hindrance, and the increase of TC hydrophilicity. Furthermore, the order of the transport-enhancement effects was generally observed as follows: DDAB > SDBS > Tween 80. The trend was controlled by the variation in the physicochemical properties of surfactants. It was noticed that the presence of Cu2+ (a model divalent cation) in the background solution, the cation-bridging contributed to the promotion effects of DDAB or Tween 80 on TC mobility. Interestingly, SDBS considerably suppressed TC transport due to the precipitation of SDBS-Cu2+ complexes onto sand surfaces. Moreover, the enhancement order of surfactants at pH 5.0 was similar to that pH 7.0. However, DDAB could inhibit TC transport in sand columns at pH 9.0, which were mainly caused by the decrease of electrostatic repulsion and the hydrophobicity induced by the binding cationic surfactant. Findings from this work provide novel insight into involvement of surfactants in antibiotic transport behaviors in the subsurface environment.


Asunto(s)
Polisorbatos , Tensoactivos , Antibacterianos , Porosidad , Arena , Tensoactivos/química , Tetraciclina
5.
Ecotoxicol Environ Saf ; 225: 112755, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34500388

RESUMEN

Biochar (BC) derived from agricultural biomass is effective at immobilizing phthalate in the agricultural soil environment. In this study, we assessed the effects of 0.5%, 1%, and 2% BC and Fe-Mn oxide-modified biochar (FMBC) addition on dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) residues and biochemical characteristics in the rhizosphere soil of mature wheat polluted with DBP and DEHP using a pot experiment. Scanning electron microscopy showed that the surfaces and pores of BC and FMBC adhered soil mineral particles after remediation. Therefore, DBP and DEHP residues were increased in BC- and FMBC-treated soils. Illumina HiSeq sequencing showed that, compared with the control, BC and FMBC addition significantly enhanced the relative abundance of Firmicutes and reduced Proteobacteria. The abundance of Sphenodons and Pseudomonas, which degrade phthalates, tended to be higher in FMBC-amended soils than in BC-amended and control soils. This result may be related to an increase in available nutrients and organic matter following BC and FMBC application. Subsequently, the changes in soil bacterial abundance and community structure induced an increase in polyphenol oxidase, ß-glucosidase, neutral phosphatase, and protease activity in BC and FMBC remediation. In comparison with the BC treatment, FMBC addition had a significantly positive effect on enzyme activity, and the microbial structure and was therefore more effective at immobilizing DBP and DEHP in the soil. Thus, our findings strongly suggest that FMBC is a reliable remediation material for phthalate-contaminated soil.


Asunto(s)
Ácidos Ftálicos , Suelo , Carbón Orgánico , Óxidos
6.
Environ Pollut ; 284: 117179, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33906035

RESUMEN

A pot experiment was carried out on brown soil polluted by dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) to investigate the effects of biochar (BC) derived from corn straw and Fe-Mn oxide modified biochar composites (FMBC) on the bioavailability of DBP and DEHP, as well as ecosystem responses in rhizosphere soil after wheat ripening. The results indicate that the application of BC and FMBC significantly increases soil organic matter, pH, available nitrogen (AN), Olsen phosphorus, and available potassium (AK); reduces the bioavailability of DBP and DEHP; enhances the activities of dehydrogenase, urease, protease, ß-glucosidase, and polyphenol oxidase; and decreases acid phosphatase activity. No changes in richness and diversity, which were measured by Illumina MiSeq sequencing, were observed following BC and FMBC application. The bacterial community structure and composition varied with DBP/DEHP concentrations and BC/FMBC additions in a nonsystematic way and no significant trends were observed. In addition, FMBC exhibited better performance in increasing soil properties and decreasing the bioavailability of DBP and DEHP compared with BC. Hence, the FMBC amendment may be a promising way of developing sustainable agricultural environmental management.


Asunto(s)
Contaminantes del Suelo , Triticum , Carbón Orgánico , Ecosistema , Ácidos Ftálicos , Suelo , Contaminantes del Suelo/análisis
7.
Environ Sci Pollut Res Int ; 28(26): 34344-34354, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33644839

RESUMEN

A detailed study of nanomaterials has revealed their broad application prospects. However, the presence of carbon nanotubes (CNTs) in the environment has been increasing and has aroused concerns regarding their toxicity to crops when combined with heavy metals. In the present study, the effects of Cd on the photosynthetic capacity and antioxidant activity of wheat seedlings in the presence of single-walled CNTs (SW) and multi-walled CNTs (MW) were investigated. Our results indicated that SW (5-40 mg L-1) and MW (10-40 mg L-1) significantly increased the oxidative stress response of wheat seedlings to Cd. Compared with Cd alone, CNTs combined with Cd decreased net photosynthetic rate, stomatal conductance, transpiration rate, primary maximum photochemical efficiency of photosystem II, actual quantum yield, photosynthetic electron transport rate, root canal protein, and ribulose-1,5-bisphosphate carboxylase/oxygenase content. Moreover, combined treatments increased the content of superoxide anion, superoxide dismutase, guaiacol peroxidase, cytochrome, and malondialdehyde in wheat seedlings. Moreover, membrane lipid peroxidation was aggravated, causing serious damage to the wheat membrane system. In addition, the toxicity of the SW treatment and the combined treatment with SW and Cd was higher than that of the MW treatment.


Asunto(s)
Nanotubos de Carbono , Plantones , Antioxidantes , Cadmio/toxicidad , Fotosíntesis , Plantones/metabolismo , Superóxido Dismutasa/metabolismo , Triticum/metabolismo
8.
Ecotoxicol Environ Saf ; 208: 111624, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396144

RESUMEN

Phthalate esters (PAEs), such as dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP), are used extensively as additives and plasticizers, and have become ubiquitous in the environment. PAEs in the soil could have adverse effects on crop plants as well as humans via accumulations in food chain. Thus, it is important to explore strategies to reduce the bioavailability of phthalate esters. We investigated the effects of Fe-Mn oxide-modified biochar composite (FMBC) applications on the quality of wheat grown in DBP- and DEHP-polluted brown soil. The application of FMBC and biochar (BC) increased the wheat grain biomass by 9.71-223.01% and 5.40-120.15% in the DBP-polluted soil, and 10.52-186.21% and 4.50-99.53% in the DEHP-spiked soil in comparison to the controls. All FMBC treatments were better than the BC treatments, in terms of decreasing DBP and DEHP bioavailability for the wheat grains. The activities of the glutamine synthetase and glutamic-pyruvic transaminase in the flag leaves at the filling stage and of granule-bound starch synthase, soluble starch synthase, and adenosine diphosphate-glucose pyrophosphorylase in the grains at maturity increased significantly with increases in either the BC or FMBC applications. This, in turn, increased the starch, protein, and amino acid content in the wheat grains. Compared with the BC treatment, the FMBC amendment induced only slight increases in the aforementioned factors. This study offers novel insights into potential strategies for decreasing PAEs bioavailability in soil, with potential positive implications for crop quality and environmental health improvements.


Asunto(s)
Carbón Orgánico/química , Restauración y Remediación Ambiental/métodos , Ácidos Ftálicos/química , Contaminantes del Suelo/metabolismo , Triticum/fisiología , Dibutil Ftalato/análisis , Dibutil Ftalato/metabolismo , Dietilhexil Ftalato/metabolismo , Grano Comestible/química , Contaminación Ambiental , Ésteres/análisis , Humanos , Hierro/análisis , Óxidos/análisis , Plastificantes/análisis , Suelo/química , Contaminantes del Suelo/análisis , Triticum/metabolismo
9.
Chemosphere ; 270: 129428, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33388501

RESUMEN

We used a pot experiment to investigate the effectiveness of 0.5, 1.0, and 2.0% biochar (BC) or iron-manganese oxide modified biochar (FMBC) additions on the biomass, enzyme activity, and grain quality of wheat plants grown in dibutyl phthalate (DBP) and di-(2-ethylhcxyl) phthalate (DEHP) polluted fluvo-aquic soils, as well as the bioavailability of DBP and DEHP. BC and FMBC applications significantly reduced DBP and DEHP accumulation in grains, which enhanced the content of starch and protein-related enzyme, thereby improving yield, and starch and protein content in wheat grains and increasing the content of minerals including Fe, Mn, K and Ca. Molecular docking assays showed that DBP and DEHP could bind to starch synthase (GBSS) through hydrogen bonds and intermolecular forces, which may have hindered the entry of substrates or occupied the binding sites of the reactants, thus inhibiting the activity of GBSS. In addition, FMBC treatment had a better inhibitory effect on the phytotoxicity of DBP and DEHP on wheat grain than BC treatment. This result might be attributed to the fact that FMBC has more functional groups and porous structure, and larger specific surface area. In summary, these findings contribute to our understanding of the mechanism of phthalate phytotoxicity, which may help us prevent/reduce it in the future.


Asunto(s)
Dietilhexil Ftalato , Contaminantes del Suelo , Carbón Orgánico , Dibutil Ftalato , Simulación del Acoplamiento Molecular , Óxidos , Ácidos Ftálicos , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Triticum
10.
Environ Pollut ; 268(Pt B): 115870, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33120154

RESUMEN

Hydrophobic microplastics with a relatively large surface area can act as carriers for pollutants and exert a series of indirect effects on crop plants. This study investigated the toxic effects of small polystyrene (SPS, 100-1000 nm) and large polystyrene (LPS, >10,000 nm) microplastics, on lettuce under di-butyl phthalate (DBP) stress. The results indicated that single SPS, LPS, and DBP treatments significantly decreased lettuce biomass, and induced oxidative stress and damaged lettuce leaves and roots. According to Gaussian analysis, SPS or LPS could interact with DBP through van der Waals force, thereby reducing lettuce biomass and DBP enrichment in roots and leaves under combined treatments, increasing antioxidant enzyme activities and exacerbating oxidative stress and subcellular damage, compared to single DBP treatments. Observation using scanning electron microscopy demonstrated that polystyrene (PS) adhered to the root surfaces, which, in turn, caused physical blockage of the root pores. Cell membrane and wall damage was observed during PS and/or DBP exposures, as identified by transmission electron microscopy. Molecular docking illustrated that DBP and monobutyl phthalate could interact with superoxide dismutase residues through hydrogen bonding, π-π stacking, alkyl conjugation, and van der Waals forces. Interestingly, there were no statistical differences between the phytotoxicity of nano- and microplastics to lettuce. These findings showed that PS aggravated DBP-induced phytotoxicity.


Asunto(s)
Dibutil Ftalato , Lactuca , Disponibilidad Biológica , Dibutil Ftalato/toxicidad , Simulación del Acoplamiento Molecular , Plásticos , Poliestirenos/toxicidad
11.
J Hazard Mater ; 398: 122859, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-32480324

RESUMEN

Although graphene oxide (GO) has been widely used to enhance soil quality and crop yield, there is currently little information regarding the effects of foliar application of GO on cadmium (Cd) toxicity to plants. In this study, we investigated the response to GO in lettuce cultivated under Cd stress in hydroponic conditions. Lettuce was grown from seeds in a nutrient solution supplemented with 2 mg/L Cd and the leaves were sprayed with 0, 30, and 60 mg/L GO. The results indicated that application of 30 mg/L GO significantly increased the total length, surface area, average diameter, and hair number of lettuce roots, and effectively alleviated the negative effects of Cd on root growth. Furthermore, foliar application of 30 mg/L GO, but not 60 mg/L GO, significantly improved the quality of lettuce, including reduction in Cd accumulation in leaves and roots and increase in soluble sugar, protein, and vitamin C content. Transmission electron microscopy revealed that GO nanoparticles, which entered the leaves and were subsequently transported to the roots via the vascular system (phloem), reduced the damaging effect of Cd on cellular organelles, including the cell wall and membrane, chloroplasts, and starch granules. The effect may be attributed to the absorption of GO by lettuce cells, where it fixed Cd2+, thus reducing Cd2+ bioavailability, or to the improvement of Cd tolerance through regulation of lettuce metabolic pathways. Gaussian simulation analysis revealed that Cd caused significant changes in the GO molecule, resulting in detachment of an epoxy group from the GO carbon ring and breakage of OH bonds in hydroxyl groups, whereupon the oxygen freed from the OH bond formed a new bond with Cd. Collectively, these results indicate that foliar application of 30 mg/L GO can enhance the tolerance of lettuce to Cd, promote plant growth, and improve nutritional quality.


Asunto(s)
Grafito , Contaminantes del Suelo , Cadmio/análisis , Cadmio/toxicidad , Grafito/toxicidad , Lactuca , Hojas de la Planta/química , Raíces de Plantas/química , Contaminantes del Suelo/toxicidad
12.
Chemosphere ; 240: 124931, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31561161

RESUMEN

Carbon nanotubes (CNTs) have been widely used in many scientific fields including plant sciences due to their unique physical and chemical properties. However, little is known about the toxic effects of CNTs combined with cadmium (Cd) on wheat. The aim of this study was to investigate the effects of single-walled carbon nanotubes (SW) and multi-walled carbon nanotubes (MW) on the phytotoxicity of Cd in wheat. A hydroponic culture was carried out to study wheat seedling growth in six treatments, namely Cd only (Cd); MW only (MW); SW only (SW); SW combined with Cd (SWCd); MW combined with Cd (MWCd); and a control (neither Cd nor carbon nanotubes). Compared with the Cd, SW/MW alone, CNTsCd treatments induced a reduction in total root length, root surface area, average root diameter, number of root hairs, and the dry weight of shoots and roots, which indicated that wheat growth and development was significantly inhibited. In addition, an obvious decrease in tubulins in the roots was observed. However, SW/MWCd induced a significant increase in glutathione S-transferase and cyochrome P450 in the shoots and roots, which indicated that the defense ability of wheat seedlings had improved, thus alleviating Cd stress. Moreover, Cd content increased significantly in shoot and root tissues with an increase in SW/MW content, compared to the Cd treatment. According to the transmission electron microscopy, CNTs alone destroyed the cell structure, and this devastating phenomenon was deepened after combining Cd and CNTs due to CNTs carrying Cd to attack cells. Compared with MW, SW had a greater effect on wheat seedlings. To conclude, CNTs increase the toxicity of Cd to wheat seedlings. These results are significant as they evaluate indirect phytotoxicity of CNTs for adsorbing heavy metals and plant growth regulators. In view of the widespread exposure of agricultural crops to Cd, the nanotoxicity of CNTs should be seriously considered in relation to food security in the future.


Asunto(s)
Cadmio/toxicidad , Nanotubos de Carbono/toxicidad , Raíces de Plantas/fisiología , Plantones/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Transporte Biológico , Sistema Enzimático del Citocromo P-450/metabolismo , Glutatión Transferasa/metabolismo , Hidroponía , Microscopía Electrónica de Transmisión , Reguladores del Crecimiento de las Plantas/farmacología
13.
Sci Total Environ ; 697: 133981, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31479901

RESUMEN

Di(2-ethylhexyl) phthalate (DEHP) and di(n-butyl) phthalate (DBP) are the major phthalic acid esters to be used during the plastic manufacturing process; they have emerged as pollutants that result in serious environmental problems. However, their impacts on wheat at the reproductive stage remain unclear. Here, we examined the distribution of DEHP and DBP and their respective metabolites mono(2-ethylhexyl) phthalate (MEHP) and mono-n-butyl phthalate (MBP) in mature wheat, along with the mechanism of detoxification and oxidative burst in wheat grains under DBP and DEHP stress conditions in a pot experiment. High-performance liquid chromatography showed that the contents of DBP and DEHP, as well as their metabolites, i.e., MBP and MEHP, presented the highest values in the grain, followed by the stem, leaf, and root. Entry of DBP and DEHP into the grain from the soil induced the production of reactive oxygen species, accompanied by the upregulated expression and activity of the antioxidant enzymes (e.g., cytochrome P4503A4 and peroxidase). The metacaspase type I gene was also upregulated in response to DBP and DEHP stress in grains, which is indicative of programmed cell death to maintain normal physiological activities and to resist cell damage. DBP and DEHP stress-damaged cells in the grains underwent programmed cell death by upregulating the expression levels of the metacaspase type I gene. These results provide a new perspective for improving wheat tolerance to DBP and DEHP through the use of genetic engineering strategies.


Asunto(s)
Dibutil Ftalato/metabolismo , Dietilhexil Ftalato/metabolismo , Contaminantes del Suelo/metabolismo , Triticum/fisiología , Antioxidantes/metabolismo , Ácidos Ftálicos , Plastificantes , Triticum/metabolismo
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