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1.
Environ Monit Assess ; 196(4): 361, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472544

RESUMO

In this study, we collected 56 species of fishery organisms (including fish, crustaceans, cephalopods, gastropods, and bivalves) from four seasonal survey cruises at the Dachen fishery grounds. We measured the concentrations of seven heavy metals (Cd, Zn, Cu, Pb, Cr, As, and Hg) in these fisheries organisms. We determined their trophic levels using carbon and nitrogen stable isotope techniques. We analyzed the characteristics of heavy metal transfer in the food chain. The results showed significant differences in heavy metal concentrations among different species. Among all biological groups, bivalves and gastropods exhibited higher levels of heavy metal enrichment than other biological groups, while fish had the lowest levels of heavy metal enrichment. Heavy metals exhibited different patterns of nutritional transfer in the food chain. While Hg showed a biomagnification phenomenon in the food chain, it was not significant. Cd, Zn, Cu, Pb, Cr, and As exhibited a trend of biodilution with increasing nutritional levels, except for As, which showed no significant correlation with δ15N.


Assuntos
Gastrópodes , Mercúrio , Metais Pesados , Poluentes Químicos da Água , Animais , Cádmio , Caça , Chumbo , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Metais Pesados/análise , Cadeia Alimentar , Isótopos de Nitrogênio , China , Músculos/química
2.
Molecules ; 29(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338298

RESUMO

Floating wheat is a classical herbal with potential efficacy in the treatment of hyperhidrosis. Aiming at revealing the main components and potential mechanisms of floating wheat, a comprehensive and unique phytopharmacology profile study was carried out. First, common wheat was used as a control to look for chemical markers of floating wheat. In the screening analysis, a total of 180 shared compounds were characterized in common wheat and floating wheat, respectively. The results showed that floating wheat and common wheat contain similar types of compounds. In addition, in non-targeted metabolomic analysis, when taking the contents of the constituents into account, it was found that there indeed existed quite a difference between floating wheat and common wheat and 17 potential biomarkers for floating wheat. Meanwhile, a total of seven components targeted for hyperhidrosis were screened out based on network pharmacology. Seven key differential components were screened, among which kaempferol, asiatic acid, sclareol, enoxolone, and secoisolariciresinol had higher degree values than the others. The analysis of interacting genes revealed three key genes, namely, MAP2K1, ESR1, and ESR2. The Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses showed that various signaling pathways were involved. Prolactin signaling, thyroid cancer, endocrine resistance, gonadotropin secretion, and estrogen signaling pathways were the main pathways of the intervention of floating wheat in excessive sweating, which was associated with the estrogenic response, hormone receptor binding, androgen metabolism, apoptosis, cancer, and many other biological processes. Molecular docking showed that the screened key components could form good bindings with the target proteins through intermolecular forces. This study reveals the active ingredients and potential molecular mechanism of floating wheat in the treatment of hyperhidrosis and provides a reference for subsequent basic research.


Assuntos
Medicamentos de Ervas Chinesas , Hiperidrose , Triticum , Farmacologia em Rede , Antiperspirantes , Simulação de Acoplamento Molecular , Medicina Tradicional Chinesa
3.
Angle Orthod ; 93(1): 49-56, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223213

RESUMO

OBJECTIVES: To compare two different therapeutic approaches for skeletal Class II patients with temporomandibular degenerative joint disease. MATERIALS AND METHODS: A total of 47 patients were included in this study. Group anterior repositioning splint (ARS) was treated with temporomandibular joint (TMJ) disc surgery followed by an ARS and camouflage orthodontic treatment. Group stabilization splint (SS) was treated with an SS followed by orthodontic treatment combined with orthognathic surgery. Cephalometric analysis of lateral radiographs and measurements of condylar height were evaluated before and after splints. RESULTS: In group ARS, mandibular advancement was observed after treatment in 21 of 24 patients (87.5%). The SNB angle increased by an average of 1.40 ± 1.01°. The ANB angle, overjet, Wits, and convexity decreased. Facial angle and soft tissue N Vert to pogonion increased. Vertically, MP-FH, MP-SN, y-axis, and vertical ratio decreased and ANS-Me/N-Me and S-Go/N-Me increased, suggesting a counterclockwise rotation of the mandible. In group SS, 18 of 23 patients (78.3%) showed a backward change tendency. The SNB angle reduced by 0.90 ± 0.93°. The ANB angle, overjet, Wits, convexity, and y-axis increased. The facial angle and soft tissue N Vert to soft tissue pogonion (ST N Vert to ST pogonion) decreased. Magnetic resonance imaging showed condylar height increased by 1.45 ± 3.05 mm (P = .002) in group ARS. In group SS, condylar height change was not consistent. CONCLUSIONS: TMJ disc surgery followed by ARS promoted condylar bone remodeling and regeneration. The SNB angle increased, and the severity of skeletal Class II was improved. The SS enabled the mandible to withdraw backward and revealed a retrognathic but true mandible position.


Assuntos
Má Oclusão Classe II de Angle , Sobremordida , Humanos , Mandíbula , Ossos Faciais , Disco da Articulação Temporomandibular/diagnóstico por imagem , Face , Cefalometria , Articulação Temporomandibular/patologia , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Má Oclusão Classe II de Angle/patologia , Côndilo Mandibular/diagnóstico por imagem
4.
Biology (Basel) ; 11(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36552340

RESUMO

This study aimed to investigate the practical validity of the environmental DNA (eDNA) method for evaluating fish composition and diversity in different habitats. We evaluated the fish composition and diversity characteristics of seven different habitats in the Ma'an Archipelago Special Protected Area in April 2020. The results showed that a total of twenty-seven species of fishes belonging to six orders, eighteen families, and twenty-three genera of the Actinopterygii were detected in the marine waters of the Ma'an Archipelago Special Protected Area. The dominant species in each habitat were Larimichthys crocea, Paralichthys olivaceus, and Lateolabrax maculatus. The mussel culture area had the highest number of species, with 19 fish species, while the offshore bulk load shedding platform had the lowest number of species, with 12 fish species. The rest of the habitat was not significantly different. The results showed that the mussel culture area had the highest diversity index (average value of 2.352 ± 0.161), and the offshore bulk load shedding platform had the lowest diversity index (average value of 1.865 ± 0.127); the rest of the habitat diversity indices did not differ significantly. A comparison with historical surveys showed that the eDNA technique can detect species not collected by traditional methods such as gillnets and trawls. Our study demonstrates the role of eDNA technology in obtaining fish diversity in different habitats and provides a theoretical basis for the continuous monitoring and management of fish biodiversity in protected areas.

5.
PLoS One ; 17(11): e0277281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36342951

RESUMO

The spatial heterogeneity of macroalgae in intertidal zones affects the stability of marine ecosystem communities, contributes to the maintenance of coastal biodiversity, and has an essential role in ecosystem and habitat maintenance. We explored the feasibility of applying the power law model to analyze the spatial distribution of macroalgae on Lvhua Island (Zhejiang Province, China) and characterized the intertidal spatial heterogeneity of the macroalgae present. The results showed a strong association between the spatial distribution of macroalgae in the intertidal zone and the power law model (R2 = 0.98). There was a positive association between species occurrence frequency and the spatial heterogeneity index of macroalgae species. The model also indicated there was macroalgal habitat structure at the site as the spatial heterogeneity within the community was greater than that of random distribution. The power law model reported here provides a new method for macroalgae community ecology research and could be broadly utilized to analyze the spatial pattern of macroalgae in intertidal zones.


Assuntos
Ecossistema , Alga Marinha , Biodiversidade , Ecologia , China
6.
Sensors (Basel) ; 22(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35808153

RESUMO

Probing the coverage and biomass of seaweed is necessary for achieving the sustainable utilization of nearshore seaweed resources. Remote sensing can realize dynamic monitoring on a large scale and the spectral characteristics of objects are the basis of remote sensing applications. In this paper, we measured the spectral data of six dominant seaweed species in different dry and wet conditions from the intertidal zone of Gouqi Island: Ulva pertusa, Sargassum thunbergii, Chondrus ocellatus, Chondria crassiaulis Harv., Grateloupia filicina C. Ag., and Sargassum fusifarme. The different seaweed spectra were identified and analyzed using a combination of one-way analysis of variance (ANOVA), support vector machines (SVM), and a fusion model comprising extreme gradient boosting (XGBoost) and SVM. In total, 14 common spectral variables were used as input variables, and the input variables were filtered by one-way ANOVA. The samples were divided into a training set (266 samples) and a test set (116 samples) at a ratio of 3:1 for input into the SVM and fusion model. The results showed that when the input variables were the normalized difference vegetation index (NDVI), ratio vegetation index (RVI), Vre, Abe, Rg, Lre, Lg, and Lr and the model parameters were g = 1.30 and c = 2.85, the maximum discrimination rate of the six different wet and dry states of seaweed was 74.99%, and the highest accuracy was 93.94% when distinguishing between the different seaweed phyla (g = 6.85 and c = 2.55). The classification of the fusion model also shows similar results: The overall accuracy is 73.98%, and the mean score of the different seaweed phyla is 97.211%. In this study, the spectral data of intertidal seaweed with different dry and wet states were classified to provide technical support for the monitoring of coastal zones via remote sensing and seaweed resource statistics.


Assuntos
Rodófitas , Sargassum , Alga Marinha , Biomassa
7.
Int J Mol Sci ; 23(9)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35563424

RESUMO

The black soldier fly (BSF), Hermetia illucens, has emerged as a promising species for waste bioconversion and source of antimicrobial proteins (AMPs). However, there is a scarcity of research on the element transformation efficiency and molecular characterization of AMPs derived from waste management. Here, food waste treatment was performed using BSF larvae (BSFL) in a C/N ratio of 21:1−10:1, with a focus on the C/N-dependent element bioconversion, AMP antimicrobial activity, and transcriptome profiling. The C-larvae transformation rates were found to be similar among C/Ns (27.0−35.5%, p = 0.109), while the N-larvae rates were different (p = 0.001), with C/N 21:1−16:1 (63.5−75.0%) being higher than C/N 14:1−10:1 (35.0−45.7%). The C/N ratio did not alter the antimicrobial spectrum of AMPs, but did affect the activities, with C/N 21:1 being significantly lower than C/N 18:1−10:1. The lysozyme genes were found to be significantly more highly expressed than the cecropin, defensin, and attacin genes in the AMP gene family. Out of 51 lysozyme genes, C/N 18:1 and C/N 16:1 up-regulated (p < 0.05) 14 and 12 genes compared with C/N 21:1, respectively, corresponding to the higher activity of AMPs. Overall, the element bioconversion efficiency and AMP expression can be enhanced through C/N ratio manipulation, and the C/N-dependent transcriptome regulation is the driving force of the AMP difference.


Assuntos
Dípteros , Eliminação de Resíduos , Animais , Antibacterianos/farmacologia , Dípteros/genética , Alimentos , Larva/genética , Muramidase
8.
Molecules ; 27(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408544

RESUMO

Industrial processing of raspberry juice and wine generates considerable byproducts of raspberry pomace. Ellagic acids/ellagitannins, being characterized by their antioxidant and antiproliferation properties, constitute the majority of polyphenolics in the pomace and are valuable for recovery. In the present study, we developed a novel procedure with sodium bicarbonate assisted extraction (SBAE) to recover ellagic acid from raspberry wine pomace. Key parameters in the procedure, i.e., sodium bicarbonate concentration, temperature, time and solid/liquid (S/L) ratio, were investigated by single factor analysis and optimized subsequently by Response Surface Methodology (RSM). Optimal parameters for the SBAE method here were found to be 1.2% (w/v) NaHCO3, 1:93 (w/v) S/L ratio, 22 min and 100 °C. Under these conditions, the ellagic acid yield was 6.30 ± 0.92 mg/g pomace with an antioxidant activity of 79.0 ± 0.96 µmol Trolox eq/g pomace (DPPH assay), which are 2.37 and 1.32 times the values obtained by extraction with methanol-acetone-water solvent, respectively. The considerable improvement in ellagic acid extraction efficiency could be highly attributed to the reactions of lipid saponification and ellagitannin hydrolysis resulted from sodium bicarbonates. The present study has established an organic solvent-free method for the extraction of ellagic acid from raspberry wine pomace, which is feasible and practical in nutraceutical applications.


Assuntos
Rubus , Vinho , Antioxidantes/análise , Ácido Elágico/análise , Rubus/química , Bicarbonato de Sódio , Solventes/análise , Vinho/análise
9.
Sci Total Environ ; 826: 154163, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35231526

RESUMO

Insect biorefinery by black soldier fly larvae (BSFL), Hermetia illucens, has emerged as an innovative technique for the valorization of food waste. However, despite BSFL being an attractive natural source of antimicrobial proteins (AMPs), there is a scarcity of research on the antimicrobial activity and transcriptome expression of AMPs derived from BSFL following waste treatment. In the present study, food waste treatment was performed by BSFL with a substrate C/N ratio ranging from 21:1 to 10:1, marine Vibrio parahaemolyticus (VP) was selected as the model aquaculture pathogen, the antimicrobial activities of AMPs in vitro and zebrafish in vivo were examined, and the molecular mechanism of the C/N-dependent AMP difference was expounded. Findings were made that the AMP extract of C/N16:1 resulted in relatively higher antimicrobial activity in vitro than that of other C/Ns. Further, the AMPs of C/N16:1 exhibited a promising in vivo defense effect for elevating the 96-h survival rate of zebrafish from 0% to 39% after VP infection, comparable to the animal antibiotic sulfamethoxidine. The results of transcriptome analysis reveal that lysozymes were the highest expressed components in the AMP gene family. The C/N16:1 BSFL significantly up-regulated 12 out of 51 lysozyme genes compared with C/N21:1, which likely contributed to the improvement of AMP antimicrobial activity. Further, C/N16:1 significantly up-regulated the expression of lysozyme, glycosyl hydrolase and muscle protein genes compared with C/N21:1, which likely enhanced the defense ability of the immune system, the utilization of the starch-like substrate, and the mobility of the larvae, thereby facilitating the larval transformation and AMP production. Overall, such results indicate that waste C/N ratio interacted with the activity and expression of BSFL AMPs through transcriptome regulation, and the BSFL AMPs derived from food waste could be used for the defense against marine pathogens to support the sustainable development of aquaculture.


Assuntos
Dípteros , Eliminação de Resíduos , Vibrio parahaemolyticus , Animais , Antibacterianos , Alimentos , Larva , Muramidase , Peixe-Zebra
10.
PLoS One ; 17(2): e0263416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35202425

RESUMO

The Above Ground Biomass (AGB) of seaweeds is the most fundamental ecological parameter as the material and energy basis of intertidal ecosystems. Therefore, there is a need to develop an efficient survey method that has less impact on the environment. With the advent of technology and the availability of popular filming devices such as smartphones and cameras, intertidal seaweed wet biomass can be surveyed by remote sensing using popular RGB imaging sensors. In this paper, 143 in situ sites of seaweed in the intertidal zone of GouQi Island, ShengSi County, Zhejiang Province, were sampled and biomass inversions were performed. The hyperspectral data of seaweed at different growth stages were analyzed, and it was found that the variation range was small (visible light range < 0.1). Through Principal Component Analysis (PCA), Most of the variance is explained in the first principal component, and the load allocated to the three kinds of seaweed is more than 90%. Through Pearson correlation analysis, 24 parameters of spectral features, 9 parameters of texture features (27 in total for the three RGB bands) and parameters of combined spectral and texture features of the images were selected for screening, and regression prediction was performed using two methods: Random Forest (RF), and Gradient Boosted Decision Tree (GBDT), combined with Pearson correlation coefficients. Compared with the other two models, GBDT has better fitting accuracy in the inversion of seaweed biomass, and the highest R2 was obtained when the top 17, 17 and 11 parameters with strong correlation were selected for the regression prediction by Pearson's correlation coefficient for Ulva australis, Sargassum thunbergii, and Sargassum fusiforme, and the R2 for Ulva australis was 0.784, RMSE 156.129, MAE 50.691 and MAPE 28.201, the R2 for Sargassum thunbergii was 0.854, RMSE 790.487, MAE 327.108 and MAPE 19.039, and the R2 for Sargassum fusiforme was 0.808, RMSE 445.067 and MAPE 28.822. MAE was 180.172 and MAPE was 28.822. The study combines in situ survey with machine learning methods, which has the advantages of being popular, efficient and environmentally friendly, and can provide technical support for intertidal seaweed surveys.


Assuntos
Biomassa , Ecossistema , Tecnologia de Sensoriamento Remoto , Alga Marinha/crescimento & desenvolvimento , Humanos , Aprendizado de Máquina , Análise de Componente Principal , Ondas de Maré
11.
Insects ; 12(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072891

RESUMO

Biowaste treatment by black soldier fly larvae (BSFL, Hermetia illucens) has received global research interest and growing industrial application. Larvae farming conditions, such as temperature, pH, and moisture, have been critically examined. However, the substrate carbon to nitrogen ratio (C/N), one of the key parameters that may affect larval survival and bioconversion efficiency, is significantly less studied. The current study aimed to compare the nitrogen supplying effects of 9 nitrogen species (i.e., NH4Cl, NaNO3, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, w/w), soybean flour, and fish meal) during food waste larval treatment, and further examine the C/N effects on the larval development and bioconversion process, using the C/N adjustment with urea from the initial 21:1 to 18:1, 16:1, 14:1, 12:1, and 10:1, respectively. The food wastes were supplied with the same amount of nitrogen element (1 g N/100 g dry wt) in the nitrogen source trial and different amount of urea in the C/N adjustment trial following larvae treatment. The results showed that NH4Cl and NaNO3 caused significant harmful impacts on the larval survival and bioconversion process, while the 7 organic nitrogen species resulted in no significant negative effect. Further adjustment of C/N with urea showed that the C/N range between 18:1 and 14:1 was optimal for a high waste reduction performance (73.5-84.8%, p < 0.001) and a high larvae yield (25.3-26.6%, p = 0.015), while the C/N range of 18:1 to 16:1 was further optimal for an efficient larval protein yield (10.1-11.1%, p = 0.003) and lipid yield (7.6-8.1%, p = 0.002). The adjustment of C/N influenced the activity of antioxidant enzymes, such as superoxide dismutase (SOD, p = 0.015), whereas exerted no obvious impact on the larval amino acid composition. Altogether, organic nitrogen is more suitable than NH4Cl and NaNO3 as the nitrogen amendment during larval food waste treatment, addition of small amounts of urea, targeting C/N of 18:1-14:1, would improve the waste reduction performance, and application of C/N at 18:1-16:1 would facilitate the larval protein and lipid bioconversion process.

12.
Chemosphere ; 257: 127140, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32526467

RESUMO

The recent increase in municipal sludge worldwide has led to a great deal of interest in developing an efficient and environmentally friendly sludge treatment method. In the paper, the treatment of municipal sludge by hydrothermal oxidation (HTO) process with H2O2 as the oxidant was proposed. The impacts of HTO temperature and H2O2 mass fraction on the distribution of products, the moisture content, the migration behaviors of the heavy metals (HMs) of the resulted solid products, the concentration of volatile fatty acids (VFAs) and NH3-N contained in the resulted aqueous phase products and the pH value were investigated. The results indicated that the sludge reduction was achieved by HTO treatment, the increasing H2O2 mass fraction and HTO temperature can significantly improve the dewatering performance of the sludge. The potential toxicity fraction of Pb and Cd contained in the resulted solid residual increased with the increasing HTO severity and the potential toxicity fraction of solid residues was still lower than that of raw material. Acetic acid was the main VFAs produced from HTO treated sludge, and its concentration reached to the maximum value of 2923.41 mg/L at 230 °C under H2O2 mass fraction of 15%. The change in the pH of the resulted aqueous phase products was caused by the competition between the acidic (VFAs or CO2) or alkaline (NH3-N) substances derived from the sludge during HTO process. The HTO process was expected to be an efficient method for municipal sludge treatment due to its mild conditions and high heavy metal safety.


Assuntos
Eliminação de Resíduos Líquidos , Ácidos , Peróxido de Hidrogênio , Governo Local , Metais Pesados/química , Oxidantes , Oxirredução , Esgotos/química , Temperatura
13.
Bioresour Technol ; 263: 289-296, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29753262

RESUMO

The typical properties and yield of the refined hydrothermolytic acid (RHTA) and refined hydrothermolytic oxidation acid (RHOA) respectively prepared from cotton stalk by the hydrothermolysis process with and without hydrogen peroxide at 180-280 °C were investigated. The pH of RHOA at 180-260 °C is lower than that of RHTA. The yield of RHOA prepared at 180-280 °C is higher than that of RHTA except 230 °C. Besides, the variation trend of RHOA yield at 180-260 °C is in accordance with that of RHTA yield at 200-280 °C. The composition of RHTA and RHOA were determined using gas chromatography and mass spectrometry. The acids content of RHOA at 200 °C reaches the maximum. The phenols of RHOA at 200-230 °C is significantly higher than that of RHTA. Under oxidation atmosphere, the formation of ketones is inhibited and the secondary reactions of furan derivatives is promoted. Overall, the oxidation processing can alleviate the severe hydrothermolysis conditions for preparing post-hydrothermolysis acid.


Assuntos
Ácidos , Gossypium , Peróxido de Hidrogênio , Cromatografia Gasosa-Espectrometria de Massas , Oxirredução , Fenóis
14.
Bioresour Technol ; 254: 231-238, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29413928

RESUMO

The yield and pH of the refined aqueous product (RAP) prepared by the hydrothermolysis of cotton stalk (CS) were investigated using response surface methodology with the variation of three parameters: CS/water ratio of 0.05-0.15w/w, temperature of 180-280 °C, and retention time of 0-30 min. At the best formulation (0.05w/w, 264.36 °C and 0 min), the yield and pH of RAP were 82.8% and 3.95, respectively. Additionally, the organic compounds contained in RAP prepared under the respective optimal formulation (pH: 0.05w/w, 251.43 °C and 0 min, yield: 0.05w/w, 280.00 °C and 0 min) were determined by gas chromatography and mass spectrometry. The results show that the kinds of compounds in RAP are identical or similar to those in the wood vinegar (WV), but their contents is slightly higher than that of the WV. In sum, it is feasible that RAP has the enormous potential to be utilized as WV probably because of its higher quality and value than WV.


Assuntos
Ácido Acético , Metanol , Fibra de Algodão , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos
15.
Waste Manag ; 75: 333-339, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29433900

RESUMO

In this paper, the thermal characteristics of sewage sludge and the transformation behavior of Pb and Cd during the thermal conversion process were addressed. The incineration process and pyrolysis process of the sewage sludge were investigated by thermogravimetric analysis. The results indicated that the thermal conversion process of the sewage sludge could be divided into three stages and the presence of oxygen could accelerate the decomposition of the sewage sludge. Furthermore, the effects of thermal conditions on the concentration ratio of Cd and Pb and their species partitioning in the residual char and ash were investigated. For the pyrolysis process, the maximum concentration ratio of Cd reached 41.64% at 500 °C and the lowest one 2.92% at 700 °C. Contrary, the concentration ratio of Pb remained above 93% as the temperature increased. Thus, the suitable temperature for the sewage sludge pyrolysis was below 500 °C. For the incineration process, the incineration temperature had great influence on the concentration ratio of Cd and Pb. When the incineration temperature increased from 700 °C to 900 °C, the concentration ratio of Cd decreased drastically from 99.32% to 10.96%. The maximum concentration ratio for Pb (95.31%) was reached at 800 °C. Besides, the lowest concentration ratio of Cd and Pb were obtained at a residence time of 30 min. The partitioning analyses of the Cd and Pb contained in the ash showed that the residence time had little effect on the partitioning of Cd and Pb, and the residual fractions of Cd and Pb were both above 90%. It was concluded that Cd and Pb were properly stabilized in the ash. Thus, Cd and Pb in the ash were difficult to be released into the environment and to cause secondary pollution.


Assuntos
Cádmio/química , Incineração , Chumbo/química , Esgotos , Metais Pesados , Volatilização
16.
Vision Res ; 109(Pt A): 107-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661165

RESUMO

Human visual cortical fields (VCFs) vary in size and anatomical location across individual subjects. Here, we used functional magnetic resonance imaging (fMRI) with retinotopic stimulation to identify VCFs on the cortical surface. We found that aligning and averaging VCF activations across the two hemispheres provided clear delineation of multiple retinotopic fields in visual cortex. The results show that VCFs have consistent locations and extents in different subjects that provide stable and accurate landmarks for functional and anatomical mapping. Interhemispheric comparisons revealed minor differences in polar angle and eccentricity tuning in comparable VCFs in the left and right hemisphere, and somewhat greater intersubject variability in the right than left hemisphere. We then used the functional boundaries to characterize the anatomical properties of VCFs, including fractional anisotropy (FA), magnetization transfer ratio (MTR) and the ratio of T1W and T2W images and found significant anatomical differences between VCFs and between hemispheres.


Assuntos
Mapeamento Encefálico , Córtex Visual , Campos Visuais/fisiologia , Adulto , Análise de Variância , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Córtex Visual/anatomia & histologia , Córtex Visual/fisiologia , Adulto Jovem
17.
Integr Zool ; 10(1): 152-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24920462

RESUMO

Recently, several rockfish species (genus Sebastes) have been reported to be soniferous. To determine whether an additional rockfish species produces sounds, passive acoustic recordings were analyzed from captive marbled rockfish (Sebastiscus marmoratus) during the non-spawning season. Three distinct sounds were identified based on frequency features. The common characteristics among all sounds were low frequency (below 300 Hz) and rapidly dampened pulses consisting of 3-5 acoustic energy cycles. During free-swimming conditions in the canvas tank, the fish produced voluntary sounds with lower frequencies than the disturbance sounds produced by individuals during prodding. Two types of sounds were identified in the disturbance context: one type consists of single or double pulses with two peak frequencies, and another type consists of a series of pulses with a single peak frequency. These results suggest that specific-species and behavior-associated sounds are potentially useful in passive acoustical surveys to monitor rockfish populations and distributions remotely.


Assuntos
Peixes/fisiologia , Som , Vocalização Animal , Acústica , Animais , Pesqueiros/métodos , Especificidade da Espécie , Natação
18.
Bioresour Technol ; 179: 98-103, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25536508

RESUMO

In the paper, the production of wood vinegar from Chinese fir sawdust (FS), cotton stalk (CS) and bamboo sawdust (BS) by carbonization process was addressed. The wood vinegar yield was investigated and the organic compounds contained were determined by gas chromatography and mass spectrometry. It was found that the refined wood vinegar yield of FS increased firstly and then decreased with increasing carbonization temperature and the highest yield reached about 25% in 350-450°C. The relative contents of acids and ketones from FS decreased and that of phenols increased with increasing temperature. The relative contents of acids and phenols in the wood vinegars produced from the samples were in the order of BS>CS>FS and that of ketones reversed. KCl solution treatment caused a decrease in the relative contents of the phenols and ketones, but an increase in that of the acids in FS wood vinegar.


Assuntos
Ácido Acético/síntese química , Biomassa , Biotecnologia/métodos , Carbono/química , Metanol/síntese química , Ácidos/análise , Cetonas/análise , Compostos Orgânicos/análise , Fenóis/análise , Potássio/farmacologia , Temperatura , Árvores/química
19.
Ying Yong Sheng Tai Xue Bao ; 25(4): 1181-7, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-25011316

RESUMO

The study of fishery community ecology depends on quality and quantity of data collected from well-designed sampling programs. The optimal sampling design must be cost-efficient, and the sampling results have been recognized as a significant factor affecting resources management. In this paper, the performances of stationary sampling, simple random sampling and stratified random sampling in estimating fish community were compared based on computer simulation by design effect (De), relative error (REE) and relative bias (RB). The results showed that, De of stationary sampling (average De was 3.37) was worse than simple random sampling and stratified random sampling (average De was 0.961). Stratified random sampling performed best among the three designs in terms of De, REE and RB. With the sample size increased, the design effect of stratified random sampling decreased but the precision and accuracy increased.


Assuntos
Ecologia/métodos , Peixes , Animais , Viés , Simulação por Computador
20.
Bioresour Technol ; 152: 86-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24280085

RESUMO

In the paper, biochar preparation from cotton stalk and bamboo sawdust by carbonization process was addressed. The physical and chemical properties and combustion characteristics of the biochar prepared using a tubular fixed bed were investigated. The combustion character index (S), the ignition temperature (Ti) and burnout temperature (Tf) were used to evaluate the combustion characteristics of the biochars. The results indicate that the yield and the volatile yield of the biochar decrease and the fixed carbon yield increases with the increase of the carbonization temperature. The ignition temperature and burnout temperature of the biochar increase and the value of S decreases when the carbonization temperature increases. The biochar produced from cotton stalk shows better combustion characteristics than the bamboo sawdust biochar does. Compared with commercial barbecue charcoal, the cotton stalk biochar produced under 600 °C can be utilized as barbecue charcoal.


Assuntos
Carbono/química , Carvão Vegetal/química , Gossypium/química , Resíduos/análise , Madeira/química , Cinética , Temperatura , Termogravimetria , Volatilização
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