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1.
Bioresour Technol ; 400: 130654, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38575095

RESUMEN

Aquaculture wastewater management is critical for environmental sustainability. This study investigates the synergistic interactions between light and dark biofilms with a Rotating Algal Biofilm (RAB) system for effective aquaculture wastewater treatment. The RAB system, optimized with a 5-day harvest time and 12-hour hydraulic retention time, demonstrated superior biomass productivity (3.3 g m-2 d-1) and total ammoniacal nitrogen removal (82.3 %). Comparative analysis of light and dark biofilms revealed their complementary roles, with the light side exhibiting higher carbon assimilation and nutrient removal efficiencies, while the dark side contributed significantly to denitrification and phosphorus removal. Microbial community analysis highlighted the dominance of key bacterial genera such as Haliangium, Methyloversatilis and Comamonadaceae, along with the algal genus Chlorella, indicating their crucial roles in nutrient cycling. This study provides insights into the operational dynamics of RAB system for sustainable aquaculture wastewater treatment.


Asunto(s)
Acuicultura , Biopelículas , Aguas Residuales , Acuicultura/métodos , Aguas Residuales/microbiología , Nitrógeno , Fósforo , Purificación del Agua/métodos , Luz , Biomasa , Eliminación de Residuos Líquidos/métodos , Bacterias/metabolismo , Desnitrificación
2.
J Nanobiotechnology ; 21(1): 107, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36964565

RESUMEN

Due to the excellent biocompatible physicochemical performance, luminogens with aggregation-induced emission (AIEgens) characteristics have played a significant role in biomedical fluorescence imaging recently. However, screening AIEgens for special applications takes a lot of time and efforts by using conventional chemical synthesis route. Fortunately, artificial intelligence techniques that could predict the properties of AIEgen molecules would be helpful and valuable for novel AIEgens design and synthesis. In this work, we applied machine learning (ML) techniques to screen AIEgens with expected excitation and emission wavelength for biomedical deep fluorescence imaging. First, a database of various AIEgens collected from the literature was established. Then, by extracting key features using molecular descriptors and training various state-of-the-art ML models, a multi-modal molecular descriptors strategy has been proposed to extract the structure-property relationships of AIEgens and predict molecular absorption and emission wavelength peaks. Compared to the first principles calculations, the proposed strategy provided greater accuracy at a lower computational cost. Finally, three newly predicted AIEgens with desired absorption and emission wavelength peaks were synthesized successfully and applied for cellular fluorescence imaging and deep penetration imaging. All the results were consistent successfully with our expectations, which demonstrated the above ML has a great potential for screening AIEgens with suitable wavelengths, which could boost the design and development of novel organic fluorescent materials.


Asunto(s)
Inteligencia Artificial , Imagen Óptica , Imagen Óptica/métodos , Fluorescencia , Aprendizaje Automático , Colorantes Fluorescentes/química
3.
J Speech Lang Hear Res ; 65(9): 3264-3275, 2022 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-35985304

RESUMEN

PURPOSE: This study aims to translate the English version of the Trans Woman Voice Questionnaire (TWVQ) to simplified Chinese (TWVQ-SC) and to examine its reliability and validity. METHOD: Standardized translation procedures were strictly followed for the translation of the TWVQ. Two hundred sixty trans woman and 128 cis woman subjects completed sociodemographic investigation, the TWVQ-SC, and the Voice Handicap Index-10 (VHI-10) online. Internal consistency was examined by Cronbach reliability coefficient (Cronbach α). Test-retest reliability was quantified by intraclass correlation coefficient (ICC). Content validity, structural validity, and discriminant validity were examined by expert panel's judgment, factor analysis, Spearman's rank correlation coefficient, and the Mann-Whitney U test. RESULTS: The Cronbach α of the TWVQ-SC was .969 and the ICC was .841, indicating excellent internal consistency and good test-retest reliability. The four principal factors explained 21.345%, 18.592%, 13.551%, and 12.027% of the variance respectively with the cumulative contribution rate 65.514%. There was a strong correlation between the total score of the TWVQ-SC and that of the VHI-10 (r = .858, p < .001), indicating good structural validity. The total score of the TWVQ-SC of the trans woman subjects was significantly higher than that of the cis woman subjects (z = 14.590, p < .05), indicating good discriminant validity. CONCLUSION: The TWVQ-SC exhibits overall high reliability and validity, qualified to be applied as a reliable clinical tool to evaluate trans women's voice in mainland China.


Asunto(s)
Evaluación de la Discapacidad , Traducciones , China , Femenino , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
4.
Comput Math Methods Med ; 2022: 7926114, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35770117

RESUMEN

The objective of this study was to investigate the application of dynamic contrast-enhanced CT images in the nursing of patients with gastroesophageal varices (GOV) treated by digestive endoscopy and its role in relieving bleeding symptoms. A total of 60 patients with liver cirrhosis and GOV were selected as the research objects. According to whether CT was used to evaluate the position of tissue adhesion embolism, the patients were divided into the control group (24 cases) and the observation group (36 cases). The treatment effect and bleeding situation of patients in the two groups were analyzed and compared. The results showed that the main portal vein pressure (17.24 ± 1.02 cmH2O), liver function recovery effect (2.84 ± 0.45 points), and total effective rate (100%) in observation group were better than those in control group (9.70 ± 1.22 cmH2O, 0.95 ± 0.72 points, and 79.17%, respectively) (P < 0.05). In addition, the bleeding rate in observation group (0%) was significantly lower than that in control group (16.67%) (P < 0.05). In conclusion, dynamically enhanced CT scan images combined with digestive endoscopy can help improve the therapeutic effect of GOV and reduce postoperative bleeding, which was worthy of clinical application and promotion.


Asunto(s)
Várices Esofágicas y Gástricas , Várices , Endoscopía Gastrointestinal , Várices Esofágicas y Gástricas/diagnóstico por imagen , Hemorragia , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico por imagen , Vena Porta , Tomografía Computarizada por Rayos X
5.
Environ Pollut ; 303: 119180, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35307495

RESUMEN

Antibiotics usage in animal production is considered a primary driver of the occurrence, supply and spread of antibiotic resistance genes (ARGs) in the environment. Pig farms and fish ponds are important breeding systems in food animal production. In this study, we compared and analyzed broad ARGs profiles, mobile genetic elements (MGEs) and bacterial communities in a representative pig farm and neighboring fish ponds around Poyang Lake, the largest freshwater lake in China. The factors influencing the distribution of ARGs were also explored. The results showed widespread detection of ARGs (from 57 to 110) among 283 targeted ARGs in the collected water samples. The differences in the number and relative abundance of ARGs observed from the pig farm and neighboring fish ponds revealed that ARG contamination was more serious on the pig farm than in the fish ponds and that the water treatment plant on the pig farm was not very effective. Based on the variance partition analysis (VPA), MGEs, bacterial communities and water quality indicators (WIs) codrive the relative abundance of ARGs. Based on network analysis, we found that total phosphorus and Tp614 were the most important WIs and MGEs affecting ARG abundance, respectively. Our findings provide fundamental data on farms in lakeside districts and provide insights into establishing standards for the discharge of aquaculture wastewater.


Asunto(s)
Antibacterianos , Estanques , Animales , Antibacterianos/farmacología , Bacterias , Farmacorresistencia Microbiana/genética , Peces/genética , Genes Bacterianos , Porcinos
6.
J Hazard Mater ; 432: 128647, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35305412

RESUMEN

As a new type of environmental pollutant, environmental antibiotic residues have attracted widespread attention, and the degradation and removal of antibiotics has become an engaging topic for scholars. In this paper, Novozym 51003 industrialized laccase and syringaldehyde were combined to degrade sulfonamides in aquaculture wastewater. Design Expert10 software was used for multiple regression analysis, and a response surface regression model was established to obtain the optimal degradation parameters. In the actual application, the degradation system could maintain a stable performance within 9 h, and timely supplement of the mediator could achieve a better continuous degradation effect. Low concentrations of heavy metals and organic matter would not significantly affect the degradation performance of the laccase-mediator system, making the degradation system suitable for a wide range of water quality. Enzymatic reaction kinetics demonstrated a strong affinity of sulfadiazine to the substrate. Ten degradation products were speculated using high-resolution mass spectrum based on the mass/charge ratios and the publication results. Four types of possible degradation pathways of sulfadiazine were deduced. This work provides a practical method for the degradation and removal of sulfonamide antibiotics in actual sewage.


Asunto(s)
Lacasa , Aguas Residuales , Antibacterianos/química , Acuicultura , Benzaldehídos , Cinética , Lacasa/metabolismo , Sulfadiazina , Sulfanilamida , Sulfonamidas/química
7.
Huan Jing Ke Xue ; 43(2): 1089-1096, 2022 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-35075883

RESUMEN

Environmental antibiotic resistance genes (ARGs) are a type of emerging pollutant that has been widely concerning. However, investigations into the contamination of ARGs in mining areas have been scarce. Here, the types, abundances, and influencing factors of ARGs and mobile genetic elements (MGEs) were investigated in soil/sediment of the Dexing copper mine area in June 2019 by using high-throughput quantitative polymerase chain reaction (HT-qPCR). Furthermore, the influence of heavy metals and MGEs factors on ARGs was studied using the multivariate statistical analysis method. The results showed that there were a variety of ARGs in the Dexing copper mining area, and the maximum detected number of ARGs was 70. At the relative abundance level, the relative abundance of individual sites reached 0.085. In the Dexing copper mine, multidrug, MLSB, ß-lactamases, tetracycline, and aminoglycoside resistance genes were the dominant ARG classes based on their numbers. The efflux pump was the most dominant resistance mechanism, followed by antibiotic deactivation and cellular protection. There was a significant positive correlation between the abundance of ARGs and MGEs (P<0.05), and TnpA04 and Inti1 were the most important MEGs in Dexing copper mine samples, indicating that horizontal gene transfer might be an important mechanism for the spread of environmental ARGs. The results of Pearson correlation analysis and RDA analysis showed that the content of Cu was significantly positively correlated with the detected numbers and abundance of ARGs (P<0.05), suggesting that the high content of Cu in the Dexing copper mining area might be an important driving factor for the formation of ARGs.


Asunto(s)
Antibacterianos , Cobre , Antibacterianos/farmacología , Cobre/toxicidad , Farmacorresistencia Microbiana/genética , Genes Bacterianos/genética , Suelo
8.
Sci Total Environ ; 788: 147934, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34134378

RESUMEN

Most previous studies have focused on the continuous exposure of aquatic organisms to nanoplastics. However, persistent pollutants in natural aquatic surroundings are a threat, and their concentrations are continuously increasing. The discussion and research into the effects of accumulative exposure to these materials are limited. Therefore, this study aimed to compare the effects of continuous and accumulative exposure to polystyrene (PS) nanoplastics (80 nm) on Chlorella pyrenoidosa during chronic toxicity. The results indicated that under conditions of continuous exposure, this alga exhibited self-recovery to defend against the negative effects of PS nanoplastics during 15-21 days of exposure (the 21-d inhibitory rate was 1.41%). However, one unanticipated finding was that during the same period of accumulative exposure, nanoplastics retained a substantial and stable inhibitory effect on the algal growth (the 21-d inhibitory rate was 6.79% in accumulative exposure for twice), indicating the invalid self-recovery of algae. The results of scanning electron microscopy demonstrated that on day 21, the degree of damage to the algal cells under accumulative exposure was more severe than that under continuous exposure. Hence, nanoplastics exerted an irreversibly negative effect on aquatic organisms depending on the pattern, frequency, concentration, and duration of exposure. This project evaluated the practical significance of nanoplastics in aquatic ecosystems.


Asunto(s)
Chlorella , Microalgas , Contaminantes Químicos del Agua , Ecosistema , Microplásticos , Poliestirenos/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
9.
Quant Imaging Med Surg ; 11(5): 1836-1853, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33936969

RESUMEN

BACKGROUND: Microvascular invasion (MVI) has a significant effect on the prognosis of hepatocellular carcinoma (HCC), but its preoperative identification is challenging. Radiomics features extracted from medical images, such as magnetic resonance (MR) images, can be used to predict MVI. In this study, we explored the effects of different imaging sequences, feature extraction and selection methods, and classifiers on the performance of HCC MVI predictive models. METHODS: After screening against the inclusion criteria, 69 patients with HCC and preoperative gadoxetic acid-enhanced MR images were enrolled. In total, 167 features were extracted from the MR images of each sequence for each patient. Experiments were designed to investigate the effects of imaging sequence, number of gray levels (Ng), quantization algorithm, feature selection method, and classifiers on the performance of radiomics biomarkers in the prediction of HCC MVI. We trained and tested these models using leave-one-out cross-validation (LOOCV). RESULTS: The radiomics model based on the images of the hepatobiliary phase (HBP) had better predictive performance than those based on the arterial phase (AP), portal venous phase (PVP), and pre-enhanced T1-weighted images [area under the receiver operating characteristic (ROC) curve (AUC) =0.792 vs. 0.641/0.634/0.620, P=0.041/0.021/0.010, respectively]. Compared with the equal-probability and Lloyd-Max algorithms, the radiomics features obtained using the Uniform quantization algorithm had a better performance (AUC =0.643/0.666 vs. 0.792, P=0.002/0.003, respectively). Among the values of 8, 16, 32, 64, and 128, the best predictive performance was achieved when the Ng was 64 (AUC =0.792 vs. 0.584/0.697/0.677/0.734, P<0.001/P=0.039/0.001/0.137, respectively). We used a two-stage feature selection method which combined the least absolute shrinkage and selection operator (LASSO) and recursive feature elimination (RFE) gradient boosting decision tree (GBDT), which achieved better stability than and outperformed LASSO, minimum redundancy maximum relevance (mRMR), and support vector machine (SVM)-RFE (stability =0.967 vs. 0.837/0.623/0.390, respectively; AUC =0.850 vs. 0.792/0.713/0.699, P=0.142/0.007/0.003, respectively). The model based on the radiomics features of HBP images using the GBDT classifier showed a better performance for the preoperative prediction of MVI compared with logistic regression (LR), SVM, and random forest (RF) classifiers (AUC =0.895 vs. 0.850/0.834/0.884, P=0.558/0.229/0.058, respectively). With the optimal combination of these factors, we established the best model, which had an AUC of 0.895, accuracy of 87.0%, specificity of 82.5%, and sensitivity of 93.1%. CONCLUSIONS: Imaging sequences, feature extraction and selection methods, and classifiers can have a considerable effect on the predictive performance of radiomics models for HCC MVI.

10.
Environ Pollut ; 284: 117413, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34049161

RESUMEN

The toxicity of nanoplastics to aquatic organisms has been widely studied in terms of biochemical indicators. However, there is little discussion about the underlying toxic mechanism of nanoplastics on microalgae. Therefore, the chronic effect of polystyrene (PS) nanoplastics (80 nm) on Chlorella pyrenoidosa was investigated, in terms of responses at the biochemical and molecular/omic level. It was surprising that both inhibitory and promoting effects of nanoplastcis on C. pyrenoidosa were found during chronic exposure. Before 13 days, the maximum growth inhibition rate was 7.55% during 10 mg/L PS nanoplastics treatment at 9 d. However, the inhibitory effect gradually weakened with the prolongation of exposure time. Interestingly, algal growth was promoted for 1-5 mg/L nanoplastics during 15-21 d exposure. Transcriptomic analysis explained that the inhibitory effect of nanoplastics could be attributed to suppressed gene expression of aminoacyl-tRNA synthetase that resulted in the reduced synthesis of related enzymes. The promotion phenomenon may be due to that C. pyrenoidosa defended against nanoplastics stress by promoting cell proliferation, regulating intracellular osmotic pressure, and accelerating the degradation of damaged proteins and organs. This study is conducive to provide theoretical basis for evaluating the actual hazard of nanoplastics to aquatic organisms.


Asunto(s)
Chlorella , Microalgas , Contaminantes Químicos del Agua , Perfilación de la Expresión Génica , Microplásticos , Estrés Oxidativo , Fotosíntesis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
11.
Sci Total Environ ; 783: 146919, 2021 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-33866172

RESUMEN

Most previous studies have focused on the toxicity of microplastics on aquatic organisms. However, research on nanoplastics is still limited and poses significant threat to aquatic organisms than microplastics. Therefore, this study investigated the effects of nanoplastics (80 nm) on the microalgae Chlorella pyrenoidosa. One unanticipated finding was that inhibition and detoxification effects existed in the interaction between nanoplastics and C. pyrenoidosa. Nanoplastics contributed the maximum inhibition rates of 27.73%, 29.64%, and 11.76% on algal growth, chlorophyll a, and Fv/Fm, respectively, which were much higher than those of microplastics. However, the inhibitory effect of nanoplastics gradually decreased with prolonged exposure time after reaching a maximum. The transcriptomic analysis explained that the inhibition effect of nanoplastics was due to the blockage of the gene expression of aminoacyl tRNA synthetase and the synthesis of related enzymes and proteins at low concentrations (10 mg·L-1). Moreover, it affected DNA damage repair and hindered photosynthesis at high concentrations (50 mg·L-1). The detoxification phenomenon is attributed to the promotion of cell proliferation, the acceleration of the degradation of damaged proteins and organs, and the regulation of intracellular osmotic pressure in algae. The results of this study provide an understanding of the mechanism underlying the interaction between nanoplastics and microalgae.


Asunto(s)
Chlorella , Microalgas , Contaminantes Químicos del Agua , Clorofila A , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
12.
J Hazard Mater ; 409: 124518, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33191018

RESUMEN

Moxifloxacin (MOX) and gatifloxacin (GAT) are fourth-generation fluoroquinolone antibiotics that are frequently detected in surface water environments and pose a threat to aquatic organisms. However, research into their toxicity to Microcystis aeruginosa, a cyanobacterium, has thus far been limited. In the present study, we investigated the effects of these antibiotics on M. aeruginosa growth, photosynthesis, oxidative stress, and microcystin (MC) release. The results of the 96 h EC50 values of MOX and GAT were 60.34 and 25.30 µg/L, respectively, and the risk quotients calculated indicated that these antibiotics could pose considerable ecological risks at actual environmental concentrations. Photosynthetic fluorescence intensity was shown to decline markedly, and Fv/Fm significantly decreased without any evidence of recovery, suggesting that the organism's photosystems were irreversibly damaged. Chlorophyll a and carotenoid content decreased, whereas the ratio of carotenoids to chlorophyll a increased, indicating that carotenoids were less susceptible to damage than chlorophyll a. The reactive oxygen species and malondialdehyde content significantly increased, as well as the superoxide dismutase and catalase activities, indicating that exposure caused serious oxidative stress. Additionally, MC release increased. These results demonstrate that the environmental risks posed by MOX and GAT should be given serious consideration, particularly as their use is increasing.


Asunto(s)
Gatifloxacina/farmacología , Microcistinas/metabolismo , Microcystis , Moxifloxacino/farmacología , Antioxidantes , Clorofila , Clorofila A , Microcystis/efectos de los fármacos , Microcystis/metabolismo , Fotosíntesis
13.
Environ Toxicol Pharmacol ; 81: 103517, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33080356

RESUMEN

As typical endocrine disrupters, nonylphenol (NP) and octylphenol (OP) are emerging pollutants that have attracted wide attention. This study investigated the toxicity effects of NP and OP on microalgae Chlorella pyrenoidosa and Scenedesmus obliquus, particularly on their growth inhibition, photosynthetic pigment, chlorophyll fluorescence, and superoxide dismutase and malondialdehyde levels. Results showed that the 96 h EC50 of NP and OP was 2.89 and 5.21 mg/L on C. pyrenoidosa, respectively, and 1.54 and 8.48 mg/L on S. obliquus, respectively. NP exerted a stronger inhibitory effect on cell growth, photosynthesis, and PSII activity, and it contributed more oxidative stress on C. pyrenoidosa than on S. obliquus. By contrast, OP exerted a stronger inhibitory effect on S. obliquus than on C. pyrenoidosa. Furthermore, the toxicity of OP to the tested microalgae was lower than that of NP. Principal component analysis (PCA) and Pearson's correlation indicate that the accumulation of reactive oxygen species is the dominant mechanism of NP and OP cellular toxicity. The principal components of NP and OP affecting microalgae are distinct in the PCA plot, and different endocrine disrupters have varying chemical-specific influences on algal cells. This study confirmed that the toxicity of NP and OP to microalgae C. pyrenoidosa and S. obliquus is chemical- and species-specific. These findings should be considered when assessing the health risk of environmental pollution.


Asunto(s)
Chlorella/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Microalgas/efectos de los fármacos , Fenoles/toxicidad , Scenedesmus/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Carotenoides/metabolismo , Chlorella/crecimiento & desarrollo , Chlorella/metabolismo , Clorofila A/metabolismo , Malondialdehído/metabolismo , Microalgas/crecimiento & desarrollo , Microalgas/metabolismo , Scenedesmus/crecimiento & desarrollo , Scenedesmus/metabolismo , Especificidad de la Especie , Superóxido Dismutasa/metabolismo
14.
Sci Total Environ ; 742: 140602, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32640389

RESUMEN

Biochar is a good adsorbent for water pollutants. However, the effects of biochar on aquatic organisms are not well understood. In this study, different amounts of biochar (CK, 0 mg/g; T1, 10 mg/g; T2, 30 mg/g) were added to sediment to study changes in water quality and its impact on three submerged macrophytes (Hydrilla verticillata, Vallisneria natans, and Ceratophyllum demersum) and the sediment microbial community. The results indicated that biochar treatments significantly increased the water pH and conductivity. Compared with the initial values, the total phosphorus (P) contents in the water of the CK, T1, and T2 treatments decreased by 78.5%, 95.0%, and 58.3%, respectively, while the total nitrogen contents increased by 26.26%, -5.81%, and 19.70%, respectively. Compared with those in CK, the relative growth rates of H. verticillata, V. natans, and C. demersum in T1 increased by 28.4%, 163.1%, and 61.3%, respectively, while those in T2 showed no significant difference except that the growth rates of H. verticillata decreased by 17.7%. The P contents of the three submerged macrophytes increased with the increase of biochar addition, except that there was no significant difference between T2 and CK for H. verticillata. Biochar treatments reduced the biomass of total microbial, bacterial, and fungal phospholipid fatty acids in the sediment for H. verticillata and V. natans, and they increased fungal: bacterial ratios in the low-dose biochar treatments for V. natans and C. demersum. This study demonstrates that the addition of biochar to sediment significantly increased the pH and conductivity, and decreased total P contents in the water. Low-dose biochar treatments were more beneficial for water quality improvements and the growth of submerged macrophytes than high-dose biochar.


Asunto(s)
Hydrocharitaceae , Calidad del Agua , Carbón Orgánico , Nitrógeno , Fósforo
15.
Ecotoxicol Environ Saf ; 195: 110484, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32200150

RESUMEN

Microplastics and nonylphenol (NP) are considered as emerging pollutant and have attracted wide attention, while their combined toxicity on aquatic organisms is barely researched. Therefore, the combined toxicity influence of NP with three types of microplastics containing polyethylene (PE1000, 13 µm and PE, 150 µm), polyamide (PA1000, 13 µm and PA, 150 µm) polystyrene (PS, 150 µm) on microalgae Chlorella pyrenoidosa was analyzed. Both growth inhibition, chlorophyll fluorescence, superoxide dismutase (SOD), malondialdehyde (MDA), and catalase (CAT) were determined. We found that single microplastics and NP both inhibited algal growth, thereby causing oxidative stress. The order of inhibition effect in single microplastics experiment was PE1000 > PA1000 > PE ≈ PS > PA. The combined toxicity experiment results indicated that the presence of microplastics had positive effect in terms of alleviating NP toxicity to C. pyrenoidosa, and the microplastics adsorption capacity to NP was the dominant contributing factor for this effect. According to the independent action model, the combined toxicity was antagonistic. Because the negative effect of smaller size microplastics on algal growth was aggravated with prolonged exposure time, the optimum effect of microplastics alleviated NP toxicity was PA1000 at 48 h, while this effect was substituted by PA at 96 h during combined toxicity. Thus, the toxicity of smaller size microplastics has a nonnegligible influence on combined toxicity. This study confirms that microplastics significantly affected the toxicity of organic pollutants on microalgae. Further research on the combined toxicity of smaller size microplastics with pollutants in chronic toxicity is needed.


Asunto(s)
Chlorella/efectos de los fármacos , Microplásticos/toxicidad , Fenoles/toxicidad , Contaminantes Químicos del Agua/toxicidad , Adsorción , Catalasa/metabolismo , Chlorella/enzimología , Chlorella/metabolismo , Interacciones Farmacológicas , Malondialdehído/metabolismo , Microalgas/efectos de los fármacos , Microalgas/enzimología , Microalgas/metabolismo , Microplásticos/química , Estrés Oxidativo , Poliestirenos/toxicidad , Superóxido Dismutasa/metabolismo , Contaminantes Químicos del Agua/química
16.
Water Res ; 174: 115603, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32092547

RESUMEN

Sewage treatment plants (STPs) are significant reservoirs of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB). Municipal STPs (MSTPs) and industrial STPs (ISTPs) are the two most important STP types in cities. In this study, the ARGs, mobile genetic elements (MGEs), and bacterial communities of selected STPs, including two MSTPs and one ISTP, in the vicinity of Poyang Lake were comprehensively investigated through high-throughput qPCR and high-throughput Illumina sequencing. The results showed that the profiles of ARGs, MGEs and bacteria differed between the ISTP and the two MSTPs, most likely due to differences in influent water quality, such as the Pb that characterized in the ISTP's influent. The longer hydraulic retention times (HRTs) of the two MSTPs than of the ISTP may also have accounted for the different profiles. Thus, a prolonged HRT in the CASS process seems to allow a more extensive removal of ARGs and bacteria in ISTPs with similar treatment process. By providing comprehensive insights into the characteristics of ARGs, MGEs and the bacterial communities of the selected MSTPs and ISTP, our study provides a scientific basis for controlling the propagation and diffusion of ARGs and ARB in different types of STPs.


Asunto(s)
Antibacterianos , Aguas del Alcantarillado , Bacterias , Farmacorresistencia Microbiana , Genes Bacterianos , Lagos
17.
Chemosphere ; 249: 126147, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32062559

RESUMEN

Here we report a set of experiments in which water blooming cyanobacteria Microcystis aeruginosa was repeatedly exposed to erythromycin. Growth inhibition increased with increasing erythromycin concentration (1-150 µg/L) upon first exposure. Maximum inhibition rate (76.06%), occurred under 150 µg/L erythromycin. Moreover, 96-h 50% effective concentration (EC50) was 22.97 µg/L, indicating that the growth of M. aeruginosa was affected by erythromycin under common environmental concentrations. Photosynthesis was hindered by chlorophyll and photosystem II limitations. Malondialdehyde, reactive oxygen species, and superoxide dismutase contents increased significantly under certain concentrations of erythromycin, but superoxide dismutase was suppressed by 150 µg/L erythromycin. Synthesis of intracellular and extracellular microcystins was promoted by 10-60 and by 20-60 µg/L erythromycin, respectively, but both were inhibited by 100-150 µg/L. Principal component analysis and Pearson's correlation revealed the accumulation of reactive oxygen species as the dominant mechanism of erythromycin toxicity to cells. M. aeruginosa repeatedly subjected to erythromycin exposure showed obvious resistance against the antibiotic, especially when treated twice with 60 µg/L erythromycin. The 96-h EC50 was 81.29 µg/L. As compared to the first exposure to erythromycin, photosynthetic and antioxidant activities increased, while growth inhibition and oxidation stress decreased upon multiple exposures. Production and release of microcystins were enhanced by repeated exposure to the antibiotic. Thus, erythromycin persistence in water should be examined, as repeated exposure may lead to serious environmental and human health hazards.


Asunto(s)
Eritromicina/toxicidad , Microcystis/efectos de los fármacos , Antibacterianos/farmacología , Clorofila/metabolismo , Cianobacterias/metabolismo , Eritromicina/farmacología , Malondialdehído , Microcistinas , Estrés Oxidativo/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Especies Reactivas de Oxígeno/farmacología , Superóxido Dismutasa/metabolismo
18.
J Agric Food Chem ; 68(6): 1645-1653, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31972072

RESUMEN

This study investigated the toxicity of trichlorfon (TCF) to the freshwater algae Chlamydomonas reinhardtii, as well as its biodegradation and metabolic fate. The growth of C. reinhardtii decreased with increasing TCF concentration, and the maximum inhibition ratio was 51.3% at 200 mg L-1 TCF compared to the control. Analyses of pigment content, chlorophyll fluorescence, and antioxidant enzymes indicated that C. reinhardtii can produce resistance and acclimatize to the presence of TCF. The variations in pH during cultivation suggested that photosynthetic microalgae have innate advantages over bacteria and fungi in remediating TCF. A 100% biodegradation rate was achieved at a maximum concentration of 100 mg L-1 TCF. Ten metabolites were identified by GC-MS, and the degradation pathways of TCF by the algae were proposed. This research demonstrated that C. reinhardtii is highly tolerant to and can efficiently degrade TCF. Thus, C. reinhardtii can be used to remove traces of TCF from natural water environments and to treat TCF-contaminated wastewater.


Asunto(s)
Chlamydomonas reinhardtii/metabolismo , Plaguicidas/metabolismo , Triclorfón/metabolismo , Biodegradación Ambiental , Cromatografía de Gases y Espectrometría de Masas , Microalgas/metabolismo , Plaguicidas/química , Plaguicidas/toxicidad , Fotosíntesis , Triclorfón/química , Triclorfón/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad
19.
Nanoscale ; 11(13): 5839-5860, 2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30892308

RESUMEN

Acoustic devices are widely applied in telephone communication, human-computer voice interaction systems, medical ultrasound examination, and other applications. However, traditional acoustic devices are hard to integrate into a flexible system and therefore it is necessary to fabricate light weight and flexible acoustic devices for audible sound generation and detection. Recent advances in acoustic devices have greatly overcome the limitations of conventional acoustic sensors in terms of sensitivity, tunability, photostability, and in vivo applicability by employing nanomaterials. In this review, light weight and flexible nanomaterial-enabled acoustic devices (NEADs) including sound generators and sound detectors are covered. Additionally, the fundamental concepts of acoustic as well as the working principle of the NEAD are introduced in detail. Also, the structures of future acoustic devices, such as flexible earphones and microphones, are forecasted. Further exploration of flexible acoustic devices is a key priority and will have a great impact on the advancement of intelligent robot-human interaction and flexible electronics.

20.
IEEE Trans Med Imaging ; 38(10): 2338-2351, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30908201

RESUMEN

Adequate medical images are often indispensable in contemporary deep learning-based medical imaging studies, although the acquisition of certain image modalities may be limited due to several issues including high costs and patients issues. However, thanks to recent advances in deep learning techniques, the above tough problem can be substantially alleviated by medical images synthesis, by which various modalities including T1/T2/DTI MRI images, PET images, cardiac ultrasound images, retinal images, and so on, have already been synthesized. Unfortunately, the arterial spin labeling (ASL) image, which is an important fMRI indicator in dementia diseases diagnosis nowadays, has never been comprehensively investigated for the synthesis purpose yet. In this paper, ASL images have been successfully synthesized from structural magnetic resonance images for the first time. Technically, a novel unbalanced deep discriminant learning-based model equipped with new ResNet sub-structures is proposed to realize the synthesis of ASL images from structural magnetic resonance images. The extensive experiments have been conducted. Comprehensive statistical analyses reveal that: 1) this newly introduced model is capable to synthesize ASL images that are similar towards real ones acquired by actual scanning; 2) synthesized ASL images obtained by the new model have demonstrated outstanding performance when undergoing rigorous tests of region-based and voxel-based corrections of partial volume effects, which are essential in ASL images processing; and 3) it is also promising that the diagnosis performance of dementia diseases can be significantly improved with the help of synthesized ASL images obtained by the new model, based on a multi-modal MRI dataset containing 355 demented patients in this paper.


Asunto(s)
Encéfalo/diagnóstico por imagen , Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Anciano , Demencia/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Marcadores de Spin
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