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1.
Animals (Basel) ; 13(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38003138

RESUMO

The regulation of duck physiology and behavior through the photoperiod holds significant importance for enhancing poultry farming efficiency. To clarify the impact of the photoperiod on group-raised duck activeness and quantify duck activeness, this study proposes a method that employs a multi-object tracking model to calculate group-raised duck activeness. Then, duck farming experiments were designed with varying photoperiods as gradients to assess this impact. The constructed multi-object tracking model for group-raised ducks was based on YOLOv8. The C2f-Faster-EMA module, which combines C2f-Faster with the EMA attention mechanism, was used to improve the object recognition performance of YOLOv8. Furthermore, an analysis of the tracking performance of Bot-SORT, ByteTrack, and DeepSORT algorithms on small-sized duck targets was conducted. Building upon this foundation, the duck instances in the images were segmented to calculate the distance traveled by individual ducks, while the centroid of the duck mask was used in place of the mask regression box's center point. The single-frame average displacement of group-raised ducks was utilized as an intuitive indicator of their activeness. Farming experiments were conducted with varying photoperiods (24L:0D, 16L:8D, and 12L:12D), and the constructed model was used to calculate the activeness of group-raised ducks. The results demonstrated that the YOLOv8x-C2f-Faster-EMA model achieved an object recognition accuracy (mAP@50-95) of 97.9%. The improved YOLOv8 + Bot-SORT model achieved a multi-object tracking accuracy of 85.1%. When the photoperiod was set to 12L:12D, duck activeness was slightly lower than that of the commercial farming's 24L:0D lighting scheme, but duck performance was better. The methods and conclusions presented in this study can provide theoretical support for the welfare assessment of meat duck farming and photoperiod regulation strategies in farming.

2.
Environ Sci Pollut Res Int ; 27(9): 9780-9789, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927736

RESUMO

Principal component analysis (PCA), positive matrix factorization (PMF), and the mean effects range-median quotient (MERM-Q) models were employed to determine occurrence levels, sources, and potential toxicological significance of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Yellow River Estuary, China. Due to the grain size of sediments, cumulative effects, and distribution of oil fields, the total concentration of the 16 U.S. Environmental Protection Agency (US EPA) priority PAHs (T-PAHs) measured in sediments along transects in the offshore area was 119.51 ± 39.58 ng g-1 dry weight (dw), which is notably higher than that measured in rivers (75.00 ± 12.56 ng g-1 dw) and estuaries (67.94 ± 10.20 ng g-1 dw). PAH levels decreased seaward along all the studied transects in coastal Bohai Bay. Multivariate statistical analyses supported that PAHs in sediments were principally derived from coal and biomass combustion, oil pollution, and vehicular emissions. Based on the MERM-Q (0.0050 ± 0.0017), PAHs were at low potential of ecotoxicological contamination level. These results provide helpful information for protecting water resources and serving sustainable development in Construction of Ecological Civilization in the Yellow River Delta.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Análise de Componente Principal , Medição de Risco , Rios
3.
Mar Pollut Bull ; 150: 110666, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669713

RESUMO

Un-restored (R0) and restored (in 2006 (R2006) and in 2002, (R2002)) coastal wetlands were selected to study phosphorus (P) storage capacity and the risk of P loss in the Yellow River Delta (YRD). The results showed that the maximum P sorption capacity (Qmax) in the wetland sediments varied between 201.8-1168.6 mg kg-1; the average value was 576.2 mg kg-1. Qmax increased with increasing time since restoration (R2002 > R2006 > R0). The eutrophication risk index (ERI) ranged between 0.27-2.07% and decreased with increasing time since restoration, but the relationship was not statistically significant (P > 0.05). A correlation analysis demonstrated that Feox, Mg, and Alox are the main P sorption agents in wetland sediments, whereas TOC, pH, and clay particles have an important effect on P sorption and release. The analysis suggests that we should restore degraded coastal wetlands to help reduce the P load to offshore waters.


Assuntos
Fósforo/análise , Rios , Áreas Alagadas , China , Eutrofização , Sedimentos Geológicos/química
4.
Ecotoxicol Environ Saf ; 159: 20-27, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29730405

RESUMO

Bioremediation, mainly by indigenous bacteria, has been regarded as an effective way to deal with the petroleum pollution after an oil spill accident. The biodegradation of crude oil by microorganisms co-incubated from sediments collected from the Penglai 19-3 oil platform, Bohai Sea, China, was examined. The relative susceptibility of the isomers of alkylnaphthalenes, alkylphenanthrenes and alkyldibenzothiophene to biodegradation was also discussed. The results showed that the relative degradation values of total petroleum hydrocarbon (TPH) are 43.56% and 51.29% for sediments with untreated microcosms (S-BR1) and surfactant-treated microcosms (S-BR2), respectively. TPH biodegradation results showed an obvious decrease in saturates (biodegradation rate: 67.85-77.29%) and a slight decrease in aromatics (biodegradation rate: 47.13-57.21%), while no significant difference of resins and asphaltenes was detected. The biodegradation efficiency of alkylnaphthalenes, alkylphenanthrenes and alkyldibenzothiophene for S-BR1 and S-BR2 samples reaches 1.28-84.43% and 42.56-86.67%, respectively. The efficiency of crude oil degradation in sediment with surfactant-treated microcosms cultures added Tween 20, was higher than that in sediment with untreated microcosms. The biodegradation and selective depletion is not only controlled by thermodynamics but also related to the stereochemical structure of individual isomer compounds. Information on the biodegradation of oil spill residues by the bacterial community revealed in this study will be useful in developing strategies for bioremediation of crude oil dispersed in the marine ecosystem.


Assuntos
Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Hidrocarbonetos/metabolismo , Poluição por Petróleo , Petróleo/metabolismo , Acidentes , Bactérias/efeitos dos fármacos , Biodegradação Ambiental , China , Polissorbatos/farmacologia , Tensoativos/farmacologia
5.
J Sci Food Agric ; 92(1): 191-6, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21815160

RESUMO

BACKGROUND: Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days. RESULTS: The sensory acceptability limit was 11-12, 6-7 and 7-8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB-N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g(-1) for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB-N values of about 25 mg 100 g(-1) should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K-values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P > 0.05) for gonads with the three treatments. CONCLUSION: Gonads with oxygen packaging had lower sensory demerit point (P < 0.05) and TVB-N values (P < 0.05), and higher relative ATP content (P < 0.01) and K-values (P < 0.05), than that with nitrogen or air packaging, with an extended shelf life of 4-5 days during storage in artificial seawater at 5 ± 1 °C.


Assuntos
Trifosfato de Adenosina/metabolismo , Ar , Conservação de Alimentos/métodos , Nitrogênio , Oxigênio , Alimentos Marinhos/análise , Strongylocentrotus , Animais , Bactérias Aeróbias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Armazenamento de Alimentos/métodos , Gônadas , Humanos , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Alimentos Marinhos/microbiologia , Alimentos Marinhos/normas , Água do Mar , Strongylocentrotus/metabolismo , Strongylocentrotus/microbiologia
6.
Chirality ; 23(5): 379-82, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21488105

RESUMO

This work reports the chiral separation of D,L-mandelic acid with cellulose membranes. Cellulose was chosen as membrane material because it possesses multichiral carbon atoms in its molecular structure unit. The flux and permselective properties of membrane using aqueous solutions of D,L-mandelic acid as feed solution was studied. The top surface and cross-section morphology of the resulting membrane were examined by scanning electron microscopy. When the membrane was prepared with 8.1 wt % cellulose and 8.1 wt % LiCl in the DMA casting solution, and the operating pressure and feed concentration of racemate were 0.0125 MPa and 0.5 mg/ml, respectively, over 90% of enantiomeric excess could be obtained. This is the first report that the cellulose membrane is used for isolating the optical isomers of D,L-mandelic acid. Chirality, 2011.


Assuntos
Celulose/química , Ácidos Mandélicos/química , Membranas Artificiais , Celulose/análise , Microscopia Eletrônica de Varredura , Pressão , Estereoisomerismo
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