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1.
Artículo en Inglés | MEDLINE | ID: mdl-39219225

RESUMEN

High level of aluminum content in Enteromorpha prolifera posed a growing threat to both its growth and human health. This study focused on exploring the factors, impacts, and process of removing aluminum from Enteromorpha prolifera using humic acid. The results showed that under experimental conditions of 0.0330 g·L-1 humic acid concentration, pH 3.80, 34 °C, and a duration of 40 min, the removal rate was up to 80.18%. The levels of major flavor components, proteins, and amino acids in Enteromorpha prolifera increased significantly after treatment, while polysaccharides and trace elements like calcium and magnesium decreased significantly. Infrared spectroscopy demonstrated that the main functional groups involved in binding with Al3+ during humic acid adsorption were hydroxyl, carboxyl, phenol, and other oxygen-containing groups. The adsorption process of Al3+ by humic acid was a spontaneous phenomenon divided into three key stages: fast adsorption, slow adsorption, and adsorption equilibrium, which resulted from both physical and chemical adsorption effects. This study provided a safe and efficient method in algae metal removal.


Asunto(s)
Aluminio , Sustancias Húmicas , Sustancias Húmicas/análisis , Aluminio/química , Adsorción , Ulva/química , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , Algas Comestibles
2.
J Environ Sci Health B ; 59(1): 9-14, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37961984

RESUMEN

Concentrations and distribution for 16 organotin compounds were studied in all kinds of foods, including seafood, agricultural products, and wine. Meanwhile, the degradation of the TBT or TPhT was also evaluated. Concentrations of total organotins in seafood, agricultural products, and wine were 1047.2, 469.4, and 13.5 µg Sn/kg. Meanwhile, the most frequently detected organotin in three kinds of samples were TPhT, MPhT, and MPhT, respectively. The results demonstrated that phenyltin may probably become an emerging organotin pollutant. Regarding seafood, organotin concentrations of fish and mollusks were much higher than those of crustaceans. At the same time, a significant positive correlation was observed between the concentrations of TBT and MBT (p < 0.05), and between DBT and MBT(p < 0.0001). Moreover, TPhT was significantly and positively associated with DPhT (p < 0.0001), suggesting that TPhT was the precursor of DPhT. Apart from the likely illegal use of OTs as biocides in antifouling paints for ships, anthropogenic activity like agricultural activity or industrial activity also caused organotin contamination. Further research and more effective measures should be formulated to protect the food safety. Meanwhile, monitoring of the organotin contamination should not only in Qinhuangdao, but also expand to the cities along Bohai Bay.


Asunto(s)
Compuestos Orgánicos de Estaño , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/análisis , Agricultura , Monitoreo del Ambiente
3.
Cell Mol Biol (Noisy-le-grand) ; 69(14): 143-149, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38279460

RESUMEN

This study aimed to investigate the possible mechanism of Micro RNA-548b-5p (miR-548b-5p) down-regulating frizzled (FZD) 7 to suppress the migration and invasion of gastric carcinoma cells. For this purpose, HGCC (Human gastric carcinoma cell) lines were selected (Hs-746T, NCI-N87, SGC-7901, MKN-45, SNU-1), and human normal gastric mucosa cells GES-1. QRT PCR was adopted to reveal and screen the cell line with low expression of mir-548b-5p (hs-746t) for research; the Hs-746T cells were randomly assigned into control group, miR-548b-5p NC group, miR-548b-5p mimic group, miR-548b-5p mimic+pc-FZD7 group. The CCK-8 assay was utilized to measure Hs-746T cell viability, while flow cytometry, Trans well chamber, and scratch test were utilized to examine the apoptotic, invasive, and migratory properties of the cells, respectively. WB was used to detect the SATB1, as well as the expression levels of proteins involved in apoptosis, including Caspase-3, Bax, and Bcl-2, as well as Matrix metalloproteinase 2 and 9 (MMP-2 and MMP-9) in SW620 cells. The binding of miR-548b-5p to FZD7 was evaluated through the dual-luciferase reporter assay. The results indicate that MiR-548b-5p showed low expression in HGCCs; in contrast to the control group (P>0.05), the Hs-746T cell viability, invasion, migration ability, MMP-2, MMP-9 protein significantly downregulated in miR-548b-5p mimic group (P<0.05), the apoptosis rate, Caspase-3, Bax protein expression were upregulated markedly, and Bcl-2 protein expression was downregulated significantly (P<0.05); in contrast to miR-548b-5p mimic group, the Hs-746T cell viability, invasion, migration ability, MMP-2, MMP-9 protein significantly were upregulated in miR-548b-5p mimic+pc-FZD7 group (P<0.05), the apoptosis rate, Caspase-3, Bax protein expression were significantly, and the level of Bcl-2 was down-regulated significantly (P<0.05); Double Luciferase Report shows that mir-548b-5p can target and regulate fzd7. It was concluded that MiR-548b-5p can suppress cell growth and migration of HGCC Hs-746T, which may be achieved by targeted down-regulation of FZD7.


Asunto(s)
Carcinoma , Receptores Frizzled , Proteínas de Unión a la Región de Fijación a la Matriz , MicroARNs , Humanos , Apoptosis/genética , Proteína X Asociada a bcl-2/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Luciferasas/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
4.
Cell Mol Biol (Noisy-le-grand) ; 69(14): 137-142, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38279459

RESUMEN

This study aimed to investigate the effect of thalidomide (Thal) regulating microRNA (miR)-524-5p/follistatin-like protein 1 (FSTL1) on the invasion ability of gastric cancer cells. For this purpose, real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the level of miR-524-5p in GES1, SUN-16, MGC-803, SGC-7901, MKN-28, and MKN-45 cells. Then the MGC-803 and MKN-45 cells would proceed to the next research. The MGC-803 and MKN-45 cells were cultured in vitro and added Thal to the final concentration of (6.25, 12.5, 25, 50, 100) µg/mL. The blank control group only added 0.1% dimethyl sulfoxide (DMSO) culture medium, and cultured for 48 hours. CCK8 was used to detect cell proliferation, and Transwell was used to detect cell invasion. The experiment was divided into a blank control group, Thal group (25 µg/mL Thal-treated cells), Thal+inhibitor NC group, and Thal+miR-524-5p inhibitor group (transfected with inhibitor NC and miR-524-5p inhibitor respectively on the basis of Thal group), cultivated for 48 h. The level of miR-524-5p in the cells was detected by RT-qPCR; the cell invasion was detected by Transwell; the expression of matrix metalloproteinase (MMP)-2, MMP-9, FSTL1 protein in the cells was detected by Western blot. The targeting relationship between miR-524-5p and FSTL1 was verified by dual luciferase. Results showed that compared with GES1 cells, the level of miR-524-5p in SUN-16, MGC-803, SGC-7901, MKN-28, and MKN-45 cells decreased (P<0.05). In MGC-803 and MKN-45 cells, compared with the blank control group, the cell proliferation rate and the number of invasions in the (50, 100) µg/mL Thal treatment groups, and the number of invasions in (6.25, 12.5, 25) µg/mL Thal treatment groups decreased (P<0.05). Compared with the blank control group, the level of miR-524-5p in the cells of the Thal group, Thal+inhibitor NC group, and Thal+miR-524-5p inhibitor group increased (P<0.05), the number of invasions, the levels of MMP-2, MMP-9 and FSTL1 proteins in cells decreased (P<0.05); compared with the Thal group and the Thal+inhibitor NC group, the level of miR-524-5p in the cells of the Thal+miR-524-5p inhibitor group decreased (P<0.05), the number of invasions, the levels of MMP-2, MMP-9, and FSTL1 proteins in the cells increased (P<0.05). Dual luciferase verification revealed that there was a targeting relationship between miR-524-5p and FSTL1. In conclusion, that can up-regulate the expression of miR-524-5p to reduce the expression of FSTL1 protein, inhibit the invasion of gastric cancer cells, and achieve alleviation of the disease.


Asunto(s)
Proteínas Relacionadas con la Folistatina , MicroARNs , Neoplasias Gástricas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Talidomida/farmacología , Movimiento Celular , Proliferación Celular/fisiología , Línea Celular Tumoral , Luciferasas/metabolismo
5.
J Sep Sci ; 46(19): e2300238, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37548129

RESUMEN

Gynostemma pentaphyllum (Thunb.) Makino represents the popular health food and supplemental product with broad pharmacological activities. The highly polar glycosides, including flavonoids and saponins, are major effective active components that contain diverse sugar positions and quantities, which result in diverse chemical polarities, making it challenging to separate and isolate these components. The present work described the rapid and efficient linear gradient counter-current chromatography to preparatively separate glycosides from aboveground parts of G. pentaphyllum. Besides, the ethyl acetate and n-butanol binary mobile phases were achieved through adjusting associated proportions. Six glycosides, including quercetin-3-O-neohesperidoside (1), kaempferol-3-O-robinobioside (2), kaempferol-3-O-neohesperidoside (3), gypenoside LVI (4), ginsenoside Rb3 (5), and gypenoside XLVI (6), were isolated at the purities greater than 98%. Moreover, electrospray ionization mass spectrometry and nuclear magnetic resonance tandem mass spectrometry were conducted for structural identification. According to our findings, the established linear gradient counter-current chromatography was an efficient approach to separate the highly polar glycosides from aboveground parts of G. pentaphyllum. Our proposed strategy can be used to separate active compounds from other complex natural products.

6.
J Sci Food Agric ; 103(2): 891-899, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36057934

RESUMEN

BACKGROUND: Iron-deficiency anemia is one severe micronutrient malnutrition and has captured worldwide attention. This study evaluated the in vitro iron absorption of two iron-binding proteins (hemoglobin and ferritin) from Tegillarca granosa. In addition, the protein structure-iron absorption relationship and the regulatory effect of hepcidin on cellular iron absorption were explored. RESULTS: Our findings revealed that both hemoglobin and ferritin extracted from T. granosa contained abundant iron-binding sites, as evidenced by stronger peaks in amide I and II regions compared with the two proteins from humans. Less ß-sheet (27.67%) structures were found in hemoglobin compared with ferritin (36.40%), probably contributing to its greater digestibility and more release of available iron. This was confirmed by the results of Caco-2/HepG2 cell culture system that showed iron absorption of hemoglobin was 26.10-39.31% higher than that of ferritin with an iron content of 50-150 µmol L-1 . This high iron absorption of hemoglobin (117.86-174.10 ng mg-1 ) could also be due to more hepcidin produced by HepG2 cells, thereby preventing ferroportin-mediated iron efflux from Caco-2 cells. In addition, the possible risk of oxidative stress was evaluated in cells post-iron exposure. In comparison with ferrous sulfate, a common iron supplement, Caco-2 cells treated with the iron-binding proteins had a 9.50-25.73% lower level of intracellular reactive oxygen species, indicating the safety of hemoglobin and ferritin. CONCLUSION: Collectively, the data of this research would be helpful for understanding the key features and potential of developing hemoglobin and ferritin from T. granosa as novel iron supplements. © 2022 Society of Chemical Industry.


Asunto(s)
Hepcidinas , Hierro , Humanos , Células CACO-2 , Técnicas de Cocultivo , Digestión , Ferritinas/metabolismo , Hemoglobinas , Hepcidinas/metabolismo , Hierro/metabolismo , Arcidae , Animales , Células Hep G2
7.
Environ Res ; 210: 112900, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35167853

RESUMEN

Vehicle emission is an important contributor to urban air pollution with the increasing number of motor vehicles. Ten typical vehicles were selected in Wuhan to study the emissions of fine particular matters (PM2.5) and associated chemical components by on-road tests through a Portable Emission Monitoring System (PEMS). The emission factors of PM2.5 and the compositions of it from different types of vehicle were obtained. Results showed that the average emission factors of PM2.5 from gasoline and diesel vehicles were 1.266 and 16.589 mg/km. As the emission standard of vehicles increased from China III to China V, PM2.5 emission factor gradually decreased from 17.385 to 1.520 mg/km. Emission rate of PM2.5 was 0.0384 mg/s under low speed, and it increased to 0.0775 and 0.0964 mg/s under the medium and high speeds. The ratio of organic carbon versus elemental carbon (OC/EC) in PM2.5 from gasoline vehicles was 6.89, which was greater than that of diesel vehicles as 3.12. Because gasoline was made of small molecules and the compression ratio of gasoline engine was relatively low, some OC remained in the area where the ignition failed in the cylinder. The top four water-soluble ions with high emission factors were Cl-, SO42-, Ca2+, and Na+, while K, Na, Ca and Mg had a larger emission factors in the 21 tested inorganic elements. These water-soluble ions and inorganic elements mainly came from the oil burning, fuel additives and engines wear. Results of PM2.5 emission characteristics would help to improve the air quality in Wuhan.


Asunto(s)
Contaminantes Atmosféricos , Gasolina , Contaminantes Atmosféricos/análisis , Carbono/análisis , China , Monitoreo del Ambiente , Gasolina/análisis , Vehículos a Motor , Material Particulado/análisis , Emisiones de Vehículos/análisis , Agua
8.
Molecules ; 27(19)2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36234919

RESUMEN

High-fat (HF) diets and low-grade chronic inflammation contribute to the development of insulin resistance and type 2 diabetes (T2D), whereas n-3 polyunsaturated fatty acids (PUFAs), due to their anti-inflammatory effects, protect against insulin resistance. Interleukin (IL)-1ß is implicated in insulin resistance, yet how n-3 PUFAs modulate IL-1ß secretion and attenuate HF diet-induced insulin resistance remains elusive. In this study, a HF diet activated NLRP3 inflammasome via inducing reactive oxygen species (ROS) generation and promoted IL-1ß production primarily from adipose tissue preadipocytes, but not from adipocytes and induced insulin resistance in wild type (WT) mice. Interestingly, endogenous synthesized n-3 polyunsaturated fatty acids (PUFAs) reversed this process in HF diet-fed fat-1 transgenic mice although the HF diet induced higher weight gain in fat-1 mice, compared with the control diet. Mechanistically, palmitic acid (PA), the main saturated fatty acid in an HF diet inactivated AMPK and led to decreased GSK-3ß phosphorylation, at least partially through reducing Akt activity, which ultimately blocked the Nrf2/Trx1 antioxidant pathway and induced TXNIP cytoplasm translocation and NLRP3 inflammasome activation, whereas docosahexaenoic acid (DHA), the most abundant n-3 PUFA in fat-1 adipose tissue, reversed this process via inducing Akt activation. Our GSK-3ß shRNA knockdown study further revealed that GSK-3ß played a pivot role between the upstream AMPK/Akt pathway and downstream Nrf2/Trx1/TXNIP pathway. Given that NLRP3 inflammasome is implicated in the development of most inflammatory diseases, our results suggest the potential of n-3 PUFAs in the prevention or adjuvant treatment of NLRP3 inflammasome-driven diseases.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ácidos Grasos Omega-3 , Resistencia a la Insulina , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Proteínas Portadoras , Dieta Alta en Grasa/efectos adversos , Ácidos Docosahexaenoicos/farmacología , Ácidos Grasos/farmacología , Ácidos Grasos Omega-3/farmacología , Glucógeno Sintasa Quinasa 3 beta , Inflamasomas/metabolismo , Resistencia a la Insulina/fisiología , Ratones , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2/genética , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ácido Palmítico/farmacología , Proteínas Proto-Oncogénicas c-akt , ARN Interferente Pequeño , Especies Reactivas de Oxígeno , Tiorredoxinas
9.
J Microencapsul ; 38(7-8): 559-571, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34637365

RESUMEN

AIM: The present study aimed to develop liposomal Rhein by employing a hydrophobic ion-pairing technique (HIP) for improved pancreatitis therapy. METHODS: F127 modified liposomal Rhein (F127-RPC-Lip) was prepared using a two-step process consisting of complexation first, followed by a film-ultrasonic dispersion step. The drug-phospholipid interaction was characterised by FT-IR and P-XRD. Particle size and morphology were investigated using DLS and TEM, respectively. Biodistribution and therapeutic efficacy of F127-RPC-Lip were evaluated in a rat model of acute pancreatitis. RESULTS: F127-RPC-Lip achieved efficient drug encapsulation after complexation with lipids through non-covalent interactions and had an average hydrodynamic diameter of about 141 nm. F127-RPC-Lip demonstrated slower drug release (55.90 ± 3.60%, w/w) than Rhein solution (90.27 ± 5.11%) within 24 h. Compared with Rhein, F127-RPC-Lip exhibited prolonged systemic circulation time, superior drug distribution, and attenuated injury in the pancreas of rats post-injection. CONCLUSIONS: HIP-assembled liposomes are a promising strategy for Rhein in treating pancreatitis.


Asunto(s)
Liposomas , Pancreatitis , Enfermedad Aguda , Animales , Antraquinonas , Pancreatitis/tratamiento farmacológico , Ratas , Espectroscopía Infrarroja por Transformada de Fourier , Distribución Tisular
10.
J Sci Food Agric ; 101(9): 3795-3803, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33306834

RESUMEN

BACKGROUND: With increasing attention being paid to food authenticity, the geographic origin of food has become a topic of interest for both consumers and producers. As far as we know, there are relatively few studies on the origin traceability of concentrated apple juice. The most commonly used methods of origin tracing research is by using stable isotopes and mineral elements technology, because these indicators are directly related to local geographical environment. RESULTS: In this study, a discriminant model was established by determining the content of the stable isotopes (δ13 C, δ18 O) and 13 mineral elements (B, Mn, Co, Ni, Cu, Sr, V, Ba, Fe, Mg, Na, Ca and Cr) in concentrated apple juice. Linear discriminant analysis (LDA), principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were employed for regional classification of samples. After data conversion and correlation analysis, spatial and quantitative prediction models were established using multiple linear regressions. Finally, the experimental results showed that the eight key variables(δ 13 C, δ 18 O, B, Ca, Mg, Cu, Sr and Na) selected by the analysis can be used to further characterize the production area. CONCLUSION: The results showed that the carbon and oxygen isotopes combined with certain mineral elements can be used to indicate the origin of concentrated apple juice. © 2020 Society of Chemical Industry.


Asunto(s)
Isótopos de Carbono/análisis , Contaminación de Alimentos/análisis , Jugos de Frutas y Vegetales/análisis , Malus/química , Minerales/análisis , Isótopos de Oxígeno/análisis , Análisis Discriminante , Geografía , Análisis de Componente Principal
11.
Pharmazie ; 76(5): 180-188, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33964990

RESUMEN

Nanoparticles (NPs) promise to address current limitations for treating acute pancreatitis (AP) via inflammatory cell-mediated sequestration. However, very few studies have explored the influence of NP size on their behavior in different stages of AP. The present work investigated the biodistribution of IR780 loaded mesoporous silica nanoparticles (MSNs) with sizes of 60, 150 or 300 nm after intravenous administration to rats of mild AP (MAP) or severe AP (SAP). Four hours after administration, MSN150 was present to a much greater extent in the pancreas than MSN60 or MSN300, irrespective of disease severity. MSN150 was present to a lower extent in pancreas, intestine and ascites in SAP than MAP rats, indicating weaker passive targeting in SAP rats. This may reflect greater blood loss and slower blood flow in SAP. These findings may guide the rational engineering of NPs with respect to particle size and disease severity for AP therapy.


Asunto(s)
Nanopartículas/administración & dosificación , Nanopartículas/uso terapéutico , Pancreatitis/tratamiento farmacológico , Tamaño de la Partícula , Dióxido de Silicio/administración & dosificación , Enfermedad Aguda , Administración Intravenosa , Animales , Masculino , Páncreas/patología , Pancreatitis/patología , Ratas , Ratas Wistar
12.
Environ Res ; 188: 109802, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32592940

RESUMEN

VOCs emissions from motor vehicles have become a main source of air pollution in many cities. However, the characteristics of VOCs emissions have not been fully elucidated. Ten representative vehicles were selected in Wuhan, China, and the VOCs emitted by these vehicles under actual working conditions were collected and analyzed through on-road tests. Results showed that the average concentrations of total VOCs emitted by gasoline and diesel vehicles were 5.9 ± 2.4 mg/m3 and 6.8 ± 3.0 mg/m3, while the average emission factors were 5.3 ± 2.2 mg/km and 33.9 ± 22.7 mg/km, respectively. The five compounds emitted at the highest levels by gasoline and diesel vehicles were hexanal, acetone, toluene, p-xylene and iso-pentane. Emission concentration of diesel vehicles was slightly higher than that of gasoline vehicles. Emission factor of diesel vehicles was much higher, because they consumed more fuel and produced more power than gasoline vehicles. The average concentrations of total VOCs emitted by China III, IV and V vehicles were 8.4 ± 1.4 mg/m3, 5.8 ± 3.4 mg/m3 and 5.3 ± 1.9 mg/m3, and their average emission factors were 21.7 ± 18.6 mg/km, 19.4 ± 28.9 mg/km and 9.1 ± 7.2 mg/km, respectively. Vehicle emissions decreased obviously as the emission standards increased. The average concentrations of total VOCs emitted under low-speed and high-speed conditions were 9.4 ± 3.5 mg/m3 and 5.5 ± 1.8 mg/m3. Concentrations of acetone, hexanal, toluene and p-xylene were the highest four VOCs under both conditions. The average emission factor of VOCs under high-speed conditions (24.0 ± 13.6 mg/km) was substantially lower than under low-speed conditions (54.0 ± 41.5 mg/km). Thus, tightening emission standards and reducing traffic congestion would help reduce VOCs emissions.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Ciudades , Monitoreo del Ambiente , Gasolina/análisis , Vehículos a Motor , Emisiones de Vehículos/análisis , Compuestos Orgánicos Volátiles/análisis
13.
Sensors (Basel) ; 20(1)2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31906062

RESUMEN

Diesel engine fault diagnosis is vital due to enhanced reliability and economic efficiency requirements. The extracted features in traditional fault diagnosis are constructed manually, which is very cumbersome because of the requirement for lots of expertise. To handle this issue, this paper proposed a variational stacked autoencoder (VSAE) to adaptively extract features from angular domain signals. As an unsupervised algorithm, VSAE can extract high-level features with the help of multiple encoding layers. Layer-wise pre-training and fine-tuning are introduced to get a better network initialization value. Moreover, the dropout technique and the batch normalization technique are carried out to prevent over-fitting and implement fast convergence. Finally, the harmony search optimizer (HSO) algorithm is introduced to get an appropriate hyper-parameter setting in the VSAE model, as well as make adaptive adjustment of the network structure. In order to verify the proposed method, the valve train fault data is collected on the diesel engine test rig under twelve operating conditions. The results indicate that the proposed scheme can effectively diagnose different degrees of intake valve fault, exhaust valve fault, and coupling fault under various operating conditions. Furthermore, the classification accuracy improved from 94.10% to 98.85%VSAE compared with stacked autoencoder (SAE) and some other traditional fault diagnosis algorithms.

14.
Sensors (Basel) ; 19(24)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842440

RESUMEN

: For a diesel engine, operating conditions have extreme importance in fault detection and diagnosis. Limited to various special circumstances, the multi-factor operating conditions of a diesel engine are difficult to measure, and the demand of automatic condition recognition based on vibration signals is urgent. In this paper, multi-factor operating condition recognition using a one-dimensional (1D) convolutional long short-term network (1D-CLSTM) is proposed. Firstly, a deep neural network framework is proposed based on a 1D convolutional neural network (CNN) and long short-Term network (LSTM). According to the characteristics of vibration signals of a diesel engine, batch normalization is introduced to regulate the input of each convolutional layer by fixing the mean value and variance. Subsequently, adaptive dropout is proposed to improve the model sparsity and prevent overfitting in model training. Moreover, the vibration signals measured under 12 operating conditions were used to verify the performance of the trained 1D-CLSTM classifier. Lastly, the vibration signals measured from another kind of diesel engine were applied to verify the generalizability of the proposed approach. Experimental results show that the proposed method is an effective approach for multi-factor operating condition recognition. In addition, the adaptive dropout can achieve better training performance than the constant dropout ratio. Compared with some state-of-the-art methods, the trained 1D-CLSTM classifier can predict new data with higher generalization accuracy.

15.
Sensors (Basel) ; 19(11)2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31174383

RESUMEN

The diesel engine has been a significant component of large-scale mechanical systems for the intelligent manufacturing industry. Because of its complex structure and poor working environment, it has trouble effectively acquiring the representative fault features. Further, fault diagnosis of the diesel engine faces great challenges. This paper presents a new fault diagnosis method for the detection of diesel engine faults under multiple operation conditions instead of conventional methods confined to a single condition. First, an adaptive correlation threshold process is designed as a preprocessing unit to enhance data quality by weakening non-impact region characteristics. Next, a feature extraction method for sound signals based on the Mel frequency cepstrum (MFC) is improved and introduced into the machinery fault diagnosis. Then, the combination of the improved feature and vibrational mode decomposition (VMD) is proposed to incorporate VMD into an effective adaptive decomposition of non-stationary signals to combine it with an excellent feature representation of the vibration signal. Finally, the vector quantization algorithm is adopted to reduce the feature dimensions and generate codebook model bases, which trains the K-Nearest Neighbor classifiers. Five comparative methods were carried out, and the experimental results show that the proposed method offers a good effect of the common valve clearance fault of diesel engines under different conditions.

16.
Molecules ; 24(2)2019 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-30641873

RESUMEN

The concentrations of trace elements in wines and health risk assessment via wine consumption were investigated in 315 wines. Samples were collected from eight major wine-producing regions in China. The concentrations of twelve trace elements were determined by inductively coupled plasma mass spectrometry (ICP-MS) and Duncan's multiple range test was applied to analyze significant variations (p < 0.05) of trace elements in different regions. Based on a 60 kg adult drinker consuming 200 mL of wine per day, the estimated daily intake (EDI) of each element from wines was far below the provisional tolerable daily intake (PTDI). Health risk assessment indicated the ingestion influence of individual elements and combined elements through this Chinese wine daily intake did not constitute a health hazard to people. However, Cr and Mn were the potential contaminants of higher health risk in Chinese wines. The cumulative impact of wine consumption on trace elements intake in the daily diet of drinkers should not be ignored due to the presence of other intake pathways.


Asunto(s)
Medición de Riesgo , Análisis Espectral , Oligoelementos/análisis , Vino/análisis , China , Humanos , Espectrometría de Masas , Control de Calidad
17.
Fish Shellfish Immunol ; 80: 191-199, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29803665

RESUMEN

Aquatic animals are frequently suffered from starvation due to restricted food availability or deprivation. It is currently known that gut microbiota assists host in nutrient acquisition. Thus, exploring the gut microbiota responses would improve our understanding on physiological adaptation to starvation. To achieve this, we investigated how the gut microbiota and shrimp digestion and immune activities were affected under starvation stress. The results showed that the measured digestion activities in starved shrimp were significantly lower than in normal cohorts; while the measured immune activities exhibited an opposite trend. A structural equation modeling (SEM) revealed that changes in the gut bacterial community were directly related to digestive and immune enzyme activities, which in turn markedly affected shrimp growth traits. Notably, several gut bacterial indicators that characterized the shrimp nutrient status were identified, with more abundant opportunistic pathogens in starved shrimp, although there were no statistical differences in the overall diversity and the structures of gut bacterial communities between starved and normal shrimp. Starved shrimp exhibited less connected and cooperative interspecies interaction as compared with normal cohorts. Additionally, the functional pathways involved in carbohydrate and protein digestion, glycan biosynthesis, lipid and enzyme metabolism remarkably decreased in starved shrimp. These attenuations could increase the susceptibility of starved shrimp to pathogens infection. In summary, this study provides novel insights into the interplay among shrimp digestion, immune activities and gut microbiota in response to starvation stress.


Asunto(s)
Digestión , Microbioma Gastrointestinal , Penaeidae , Inanición , Estrés Fisiológico , Fosfatasa Ácida/metabolismo , Amilasas/metabolismo , Animales , Bacterias/genética , Digestión/inmunología , Digestión/fisiología , Hepatopáncreas/enzimología , Lipasa/metabolismo , Muramidasa/metabolismo , Penaeidae/inmunología , Penaeidae/microbiología , Penaeidae/fisiología , Pepsina A/metabolismo , ARN Ribosómico 16S/genética , Inanición/inmunología , Inanición/microbiología , Estómago/enzimología , Estrés Fisiológico/inmunología , Estrés Fisiológico/fisiología , Superóxido Dismutasa/metabolismo
18.
Appl Microbiol Biotechnol ; 102(7): 3315-3326, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29497796

RESUMEN

One common notion is emerging that gut eukaryotes are commensal or beneficial, rather than detrimental. To date, however, surprisingly few studies have been taken to discern the factors that govern the assembly of gut eukaryotes, despite growing interest in the dysbiosis of gut microbiota-disease relationship. Herein, we firstly explored how the gut eukaryotic microbiotas were assembled over shrimp postlarval to adult stages and a disease progression. The gut eukaryotic communities changed markedly as healthy shrimp aged, and converged toward an adult-microbiota configuration. However, the adult-like stability was distorted by disease exacerbation. A null model untangled that the deterministic processes that governed the gut eukaryotic assembly tended to be more important over healthy shrimp development, whereas this trend was inverted as the disease progressed. After ruling out the baseline of gut eukaryotes over shrimp ages, we identified disease-discriminatory taxa (species level afforded the highest accuracy of prediction) that characteristic of shrimp health status. The profiles of these taxa contributed an overall 92.4% accuracy in predicting shrimp health status. Notably, this model can accurately diagnose the onset of shrimp disease. Interspecies interaction analysis depicted how the disease-discriminatory taxa interacted with one another in sustaining shrimp health. Taken together, our findings offer novel insights into the underlying ecological processes that govern the assembly of gut eukaryotes over shrimp postlarval to adult stages and a disease progression. Intriguingly, the established model can quantitatively and accurately predict the incidences of shrimp disease.


Asunto(s)
Crustáceos/microbiología , Eucariontes/fisiología , Microbioma Gastrointestinal/fisiología , Animales , Disbiosis , Eucariontes/genética
19.
Appl Microbiol Biotechnol ; 101(16): 6447-6457, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28702793

RESUMEN

Increasing evidence has revealed a close interplay between the gut bacterial communities and host growth performance. However, until recently, studies generally ignored the contribution of eukaryotes, endobiotic organisms. To fill this gap, we used Illumina sequencing technology on eukaryotic 18S rRNA gene to compare the structures of gut eukaryotic communities among cohabitating retarded, overgrown, and normal shrimp obtained from identically managed ponds. Results showed that a significant difference between gut eukaryotic communities differed significantly between water and intestine and among three shrimp categories. Structural equation modeling revealed that changes in the gut eukaryotic community were positively related to digestive enzyme activities, which in turn influenced shrimp growth performance (λ = 0.97, P < 0.001). Overgrown shrimp exhibited a more complex and cooperative gut eukaryotic interspecies interaction than retarded and normal shrimp, which may facilitate their nutrient acquisition efficiency. Notably, the distribution of dominant eukaryotic genera and shifts in keystone species were closely concordant with shrimp growth performance. In summary, this study provides an integrated overview on direct roles of gut eukaryotic communities in shrimp growth performance instead of well-studied bacterial assembly.


Asunto(s)
Eucariontes/fisiología , Interacciones Microbianas , Penaeidae/crecimiento & desarrollo , Penaeidae/microbiología , Animales , Bacterias/genética , Fenómenos Fisiológicos del Sistema Digestivo , Microbioma Gastrointestinal , Secuenciación de Nucleótidos de Alto Rendimiento , Intestinos/microbiología , Penaeidae/fisiología , Filogenia
20.
Sensors (Basel) ; 17(12)2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29244722

RESUMEN

Internal combustion engines (ICEs) are widely used in many important fields. The valve train clearance of an ICE usually exceeds the normal value due to wear or faulty adjustment. This work aims at diagnosing the valve clearance fault based on the vibration signals measured on the engine cylinder heads. The non-stationarity of the ICE operating condition makes it difficult to obtain the nominal baseline, which is always an awkward problem for fault diagnosis. This paper overcomes the problem by inspecting the timing of valve closing impacts, of which the referenced baseline can be obtained by referencing design parameters rather than extraction during healthy conditions. To accurately detect the timing of valve closing impact from vibration signals, we carry out a new method to detect and extract the commencement of the impacts. The results of experiments conducted on a twelve-cylinder ICE test rig show that the approach is capable of extracting the commencement of valve closing impact accurately and using only one feature can give a superior monitoring of valve clearance. With the help of this technique, the valve clearance fault becomes detectable even without the comparison to the baseline, and the changing trend of the clearance could be trackable.

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