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1.
J Hazard Mater ; 442: 130027, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36162305

RESUMEN

In this paper, red mud-based geopolymer microspheres (RM@GMs: 75-150 µm) was prepared by dispersion-suspension-solidification method to remove fluoride ions (F-). It was found that RM@GMs still had good mechanical properties and better F- removal effect at RM content reached 80 % of the total solid mass. The batch adsorption experiment results showed that the F- concentration (< 1.5 mg/L) reached the drinking water standard in 45 min at pH = 2 and RM@GMs dosage was 1 g/L. RM@GMs showed maximum adsorption capacity of 76.57 mg/g for F-, and the adsorption kinetics and isotherm fitted the pseudo-second-order kinetic and Langmuir isotherm model, respectively. RM@GMs exhibited excellent dynamic separation effect at the flow rate of 4 mL/min and column height of 1 cm. In addition, RM@GMs had good selectivity for F- in the competitive adsorption experiments and followed an order of: PO43- > > SO42- ≈ NO3- ≈ Cl-. In real seawater, natural surface water and tap water, RM@GMs still had excellent F- removal effect. The adsorption mechanism revealed that RM@GMs removed F- mainly through the synergistic effect of adsorption and ion exchange. Therefore, this paper provides the potential value for the large-scale utilization of RM in the application of F--containing wastewater.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Fluoruros , Aguas Residuales , Purificación del Agua/métodos , Microesferas , Contaminantes Químicos del Agua/química , Cinética , Flúor , Concentración de Iones de Hidrógeno
2.
Opt Express ; 30(20): 36592-36602, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258584

RESUMEN

The use of thermal remote sensing for marine green tide monitoring has not been clearly demonstrated due to the lack of high-resolution spaceborne thermal observation data. This problem has been effectively solved using high-spatial resolution thermal and optical images collected from the sensors onboard the Ziyuan-1 02E (ZY01-02E) satellite of China. The characteristics and principles of spaceborne thermal remote sensing of green tides were investigated in this study. Spaceborne thermal cameras can capture marine green tides depending on the brightness temperature difference (BTD) between green tides and background seawater, which shows a positive or negative BTD contrast between them in the daytime or nighttime. There is a significant difference between thermal and optical remote sensing in the ability to detect green tides; compared with optical remote sensing, pixels containing less algae are not easily distinguishable in thermal images. However, there is a good linear statistical relationship between the BTD and the optical parameter (scaled algae index of virtual baseline height of floating macroalgae, SAI(VB)) of green tides, which indicates that the BTD can be used to quantify the green tide coverage area in a pixel or biomass per area. Then, the uncertainty in thermal quantitative remote sensing of green tides was clarified according to the pixel-to-pixel relationship between optical and thermal images. In a mixed pixel, green tide coverage and algal thickness have different thermal signal responses, which results in this uncertainty. In future research, more thermally remotely sensed images with high spatial resolution are needed to increase the observation frequency in the daytime and nighttime for the dynamic monitoring of green tides.


Asunto(s)
Monitoreo del Ambiente , Algas Marinas , Monitoreo del Ambiente/métodos , Biomasa , Agua de Mar , Plantas , Océanos y Mares , China
3.
Front Neurosci ; 16: 858888, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35645719

RESUMEN

Each great architecture tells a story to make its space meaningful. What the stadium tells matters how the individual interacts with it. The potent influence of narrative in shaping our cognitive processing has been revealed and widely used. This influence, however, has not been the focus of researchers in stadium operations. The present study aimed at investigating the influence of the stadium narrative on approach-avoidance responses and the corresponding neural correlates. Participants were presented with a sequence of pictures expressing a story congruent or incongruent with the general profile of the stadium, and were required to make an enter or exit response. Results showed larger amplitudes of N400 for incongruent trials than congruent trials at the end of the narrative, indicating the feasibility of continuity editing procedure for the study of narratives. Moreover, larger amplitudes of LPP were observed in response to the stadium preceded by congruent trials than incongruent trials. This effect was more pronounced in the left than right frontal sites. The LPP suggested that a congruent narrative imparted the stadium approaching affective features, and induced approaching responses, which was consistent with the behavioral and correlational results. Our findings suggested that changes in narrative were sufficient to shape the approach-avoidance responses and the underlying neural correlates. Implications for stadium management and buildings are provided.

4.
Ecotoxicol Environ Saf ; 236: 113473, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35364507

RESUMEN

Groundwater is an important source of water, especially in semi-arid areas. The assessment of the chemical characteristics of groundwater under different land use types the associated risk to human health is of important significance for water resources utilization and protecting the ecological environment. The present study analyzed the hydrochemical characteristics and ion sources of groundwater, taking Shuangliao City as an example. The analysis was based on the field investigation (82 water samples), descriptive statistics, correlation analysis, ion proportionality coefficient method, and principal component analysis (PCA). The results indicated that the concentrations of most ions in the aquifer had wide spatiotemporal variation and were susceptible to environmental influences. NO3- showed the highest spatial variability, with concentrations ranging from 0.0 to 529.48 mg·L-1. The processes contributing the most to the chemical composition of groundwater were leaching/dissolution and cation exchange. The spatial distribution of groundwater chemistry types was visually obtained through the combined use of Piper trilinear charts and a Digital Terrain Model (DTM). The HCO3-Ca type dominated. Groundwater Cl-, SO42-, and Ca2+ were negatively correlated with the Normalized Difference Vegetation Index (NDVI) due to the absorption of inorganic salt by vegetation roots, indicating that land use types affect groundwater hydrochemistry in the area. The hazard quotient (HQ) used in the human health risk assessment (HHRA) model indicated children (0.0010-6.4162) to be at the highest risk, followed by adult females (0.0007-4.0396), with adult males (0.0005-3.0863) under the lowest risk. The spatial distribution of groundwater nitrate was shown to pose risks to children, adult females, and adult males across 62.97%, 50.01%, and 39.34% of the study area, respectively. This study can improve the understanding of groundwater evolution and the relationship between water chemistry and land use types. This study can also guide the development and utilization of groundwater resources and conservation of water quality in semi-arid areas.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Adulto , Niño , China , Monitoreo del Ambiente , Femenino , Agua Subterránea/química , Humanos , Masculino , Nitratos/análisis , Óxidos de Nitrógeno/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis , Calidad del Agua
5.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3824-3832, 2019 Nov.
Artículo en Chino | MEDLINE | ID: mdl-31833696

RESUMEN

Based on the data from four 1 hm2 permanent plots in main forest types [namely natural Larix gmelinii forest (LF), natural Betula platyphylla forest (BF), coniferous-broadleaved mixed forest (CBMF) and coniferous mixed forest (CMF)] in Great Xing'an Mountains, a comprehensive cutting index of individual tree (T), based on the commonly used spatial structure parameters [i.e., mingling (M), neighborhood comparison (U), uniform angle index (W), and competition index (CI)] and non-spatial structure parameters [tree vigor index (DC), tree stability index (DH)], was constructed using combined AHP and entropy evaluation method. The cutting process was simulated by Excel VBA to determine the best tending intensity on the basis of systematic comparison of comprehensive T-value under different tending intensities (10%, 20%, and 30%) of different forest types. The results showed that, in the initial state, the mean values of W were all 0.57, indicating a typical cluster distribution. The mean values of U ranged from 0.50 to 0.51 and the dominant degree of overall growth of trees was in a typical mean state. The mixed degree of four main forest types was generally low, with the mixed forest being obviously higher than the pure forest. The mean competition index within the stand was above 2.0, indicating higher competition pressure. The stability and growth vigor index of LF were significantly higher than those of other stands. Overall, the management urgency of BF was significantly higher than that of other stands. With regard to T-value growth rate between adjacent tending intensities, the optimal cutting intensity was 30% for LF forest and 10% for other types. The relative growth rates were 9.7%, 7.9%, 6.6% and 3.9% respectively. However, from the perspective of T-value and canopy density with different tending intensities, the optimal cutting intensity of BF was 20%, and the others were all 30%, in which the T-values were increased by 28.9%, 16.4%, 17.5% and 9.2% respectively. After simulated harvesting, stand structure was improved in various degrees and the mixed degree of tree species was increased. The horizontal distribution pattern of stand tended to random distribution. The dominance degree of dominant tree species was increased. The competition pressure of trees was decreased. DC of trees was slightly lower and the DH of trees was improved.


Asunto(s)
Bosques , Larix , Betula , China , Árboles
6.
Biosens Bioelectron ; 142: 111573, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31412314

RESUMEN

Layered transition metal dichalcogenides (TMDs) are important members in the family of two-dimensional (2D) materials. The large surface-to-volume ratio, combined with the fascinating tunable electronic and optical properties, low toxicity, unique van der Waals layered structure, and engineerable surface structure, renders 2D TMDs highly valuable for next-generation biosensing applications. Herein, the recent progress in the development of 2D TMDs-based biosensors is comprehensively reviewed, with special focus on the implementation of the structural, electronic and optical properties of 2D TMDs in the realization of high-performance biosensors with different configurations for a wide spectrum of bioanalytes and bio-species. In addition, the comparison on biosensing performances with graphene as the currently most studied 2D candidate is critically discussed. Finally, future perspectives are provided along the development progress of 2D TMDs-based biosensors which are currently undergoing an intense study. This work will lead researchers to explore more novel sensing candidates within the category of TMDs with exotic chemical composition, structure, morphologies, dimensionalities, and properties.


Asunto(s)
Técnicas Biosensibles/métodos , Metales/química , Nanoestructuras/química , Animales , Técnicas Biosensibles/instrumentación , Diseño de Equipo , Grafito/química , Grafito/toxicidad , Humanos , Metales/toxicidad , Nanoestructuras/toxicidad , Nanotecnología/instrumentación , Nanotecnología/métodos , Elementos de Transición/química , Elementos de Transición/toxicidad
7.
Beilstein J Nanotechnol ; 10: 735-745, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30993054

RESUMEN

The structurally colored surface of anodic aluminum oxide (AAO) is highly useful for decoration and anti-counterfeiting applications, which are of significance for both scientific and industrial communities. This study presents the first demonstration of the fabrication of an iridescent film of porous AAO on an industrial aluminum alloy substrate, with alternatingly electrodeposited Cu and SiO2 nanoparticles (NPs). A rainbow effect was effectively obtained for the optimized sample with appropriate alternating electrodeposition times. The structure and optical properties of a series of the electrodeposited AAO-based thin film were investigated. The Cu and SiO2 NPs were found to be uniformly deposited into the porous structure of the AAO film, and the alternating electrodeposition repeating twice led to the formation of the optimal AAO-based thin film that exhibited a rainbow effect and superior anti-corrosion performance.

8.
Physiol Genomics ; 46(7): 268-75, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24474444

RESUMEN

This study was conducted to determine the optimum ratio of lysine and methionine (Lys:Met) to enhance milk protein concentration in vitro, focusing on the regulation of genes related to the JAK2-STAT5 and the mammalian target of rapamycin (mTOR) signaling pathways. A preliminary dose response study revealed that casein concentration peaked (2.5-2.7 ppm) at a supplemental Lys concentration of 1.2 mM and Met at 0.5 mM. At the peak casein concentration cell proliferation rate also was higher. Furthermore, the expression of CSN1S1, CSN1S2, CSN2, CSN3, LALBA, JAK2, STAT5, and MTOR was upregulated with both Lys and Met compared with the control. A subsequent experiment was conducted as a 5 × 3 factorial design with supplemental Lys plus Met at different ratios. When the supplemental concentration of Lys was 1.2 mM and Met was 0.4 mM (∼3:1), the concentration of casein peaked. Therefore, we measured gene expression, mTOR protein expression, and phosphorylated mTOR (p-mTOR) in cultures incubated with 3:1 Lys:Met (Lys&Met). Expression of CSN1S1 and LALBA were the most highly expressed genes (P < 0.01). The upregulation of CSN2, CSN3, CSN1S2 isoforms (P < 0.01) and JAK2, ELF5, mTOR (P < 0.05) was also observed. Total mTOR protein expression was greater (P < 0.05) with Lys alone and also Lys&Met. However, Lys&Met resulted in the greatest (P < 0.05) p-mTOR. Results suggest that peak concentration of casein at a supplemental 3:1 Lys:Met is driven in part via upregulation of the mRNA expression of components of the JAK-STAT and mTOR pathways.


Asunto(s)
Expresión Génica , Lisina/metabolismo , Glándulas Mamarias Animales/citología , Metionina/metabolismo , Proteínas de la Leche/genética , Biosíntesis de Proteínas , Serina-Treonina Quinasas TOR/metabolismo , Transcripción Genética , Animales , Bovinos , Citometría de Flujo , Fosforilación , Reacción en Cadena en Tiempo Real de la Polimerasa
9.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): m43-4, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23476340

RESUMEN

In the title compound, {[Er(NO3)2(C6H18N3OP)4][AgWS4]} n , the polymeric anionic chain {[AgWS4](-)} n extends along [001]. The Er(III) atom in the cation is coordinated by eight O atoms from two bidentate nitrate anions and four hexa-methyl-phospho-ramide ligands in a distorted square-anti-prismatic geometry. Together with the two nitrate ligands, the cation is monovalent, which leads to the anionic chain having a [WS4Ag] repeat unit. The polymeric anionic chain has a distorted linear configuration, with W-Ag-W and Ag-W-Ag angles of 161.37 (2) and 153.548 (12)°, respectively. The title complex is isotypic with the Y, Yb, Eu, Nd, La, Dy, Sm, Lu and Tb analogues.

10.
Biotechnol Lett ; 33(1): 119-21, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20882320

RESUMEN

A sensitive and convenient "visible SYPRO" staining protocol was developed for visualizing proteins after SDS-PAGE. Gels were sensitized with SYPRO Ruby and then stained with the Coomassie Brilliant Blue G-250 protocol (Blue Silver). This combined protocol had similar or better linearity than staining with only SYPRO Ruby or Blue Silver, respectively. In addition, this method was more sensitive than that of Blue Silver, simpler than that of SYPRO Ruby, and compatible with subsequent mass spectrometry analysis.


Asunto(s)
Electroforesis en Gel Bidimensional/métodos , Proteómica/métodos , Colorantes de Rosanilina/metabolismo , Coloración y Etiquetado/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Fluorescencia , Sensibilidad y Especificidad
11.
J Agric Food Chem ; 58(6): 3741-6, 2010 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-20175540

RESUMEN

Increasing the content of alpha-linolenic acid in milk fat might be desirable to meet consumer concerns about dietary healthfulness. However, the rich content of polyunsaturated fatty acids (PUFAs) will influence the oxidative stability of milk fat. This experiment was carried out to determine the effects of infusion with different amounts of high-linolenic perilla fatty acid (HLPFA) emulsion into the duodenum of dairy cows on milk fatty acid profile and the susceptibility of milk fat to oxidation. In a crossover design, 4 multiparous Holstein cows were infused duodenally with increasing amounts (0, 40, 80, 120, or 160 g/day) of free fatty acids from HLPFA emulsion or with carrier alone. Continuous infusions (20 to 22 h/day) were for 7 days at each amount. Infusions were homogenates of HLPFA with 15 g/day of xanthan gum, 5 g/day sodium alginate, and 25 g/day Tween 80; controls received carrier only. The concentration of n-3 PUFAs, especially alpha-linolenic acid, in milk fat increased linearly as HLPFA infusion increased, but the saturated fatty acids decreased linearly. The milk production and the activity of superoxide dismutase, glutathione peroxidase, and catalase in milk tended to decrease quadratically. The milk fat percentage, however, tended to increase. The concentration of malondialdehyde increased quadratically in milk fat. Results suggest that infusion with HLPFA emulsion at varying amounts enhanced the content of n-3 PUFAs in milk fat over the length of experiment but decreased the oxidative stability of milk fat.


Asunto(s)
Bovinos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Leche/química , Ácido alfa-Linolénico/metabolismo , Animales , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/análisis , Grasas de la Dieta/metabolismo , Ácidos Grasos Insaturados/análisis , Femenino , Oxidación-Reducción , Ácido alfa-Linolénico/administración & dosificación , Ácido alfa-Linolénico/análisis
12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): m1657-8, 2010 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-21589322

RESUMEN

Hexa-methyl-phospho-ramide (hmp), tetra-thio-tungstate, silver sulfide and cerium nitrate were self-assembled to form a one-dimensional anionic [Ag(4)W(4)S(16)](n) (4n-) chain in the title compound, {[Ce(NO(3))(2)(C(6)H(18)N(3)OP)(4)][AgWS(4)]}(n). The asymmetric unit contains four crystallographically independent [Ce(hmp)(4)(NO(3))(2)](+) cations, which leads to a one-dimensional polymeric anionic chain having a tetra-valent [W(4)S(16)Ag(4)] repeat unit. Each central Ce atom is coordinated by eight O atoms from two chelating nitrate and four hmp ligands, which gives rise to a distorted square-anti-prismatic structure. The polymeric chain with average W-Ag-W and Ag-W-Ag bond angles of 163.75 and 151.84°, respectively, presents a distorted linear configuration. The title complex with a non-centrosymmetric structure, is analogous to the Yb, Y, Eu, Nd, La and Dy isomorphs, which exhibit centrosymmetric structures.

13.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 10): m1193-4, 2010 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-21587356

RESUMEN

Hexa-methyl-phospho-ramide (hmp), tetra-thio-tungstate, silver sulfide and dysprosium nitrate were self-assembled, forming an anionic [AgWS(4)](n) (n) (-) chain in the title compound, {[Dy(NO(3))(2)(C(6)H(18)N(3)OP)(4)][AgWS(4)]}(n). The central Dy atom in the cation is coordinated by eight O atoms from two didentate nitrate and four hmp ligands, giving rise to a distorted square anti-prismatic structure. Together with the two nitrate ligands, the cation is univalent, which leads to the anionic chain having a [WS(4)Ag] repeat unit. The polymeric anionic chain, with W-Ag-W and Ag-W-Ag angles 161.16 (2) and 153.606 (11)°, respectively, presents a distorted linear configuration. The title compound is isotypic with other rare earth complexes.

14.
PLoS One ; 4(11): e7636, 2009 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-19888476

RESUMEN

BACKGROUND: The objective of this study was to establish a culture system and elucidate the unique characteristics of a bovine mammary epithelial cell line in vitro. METHODOLOGY: Mammary tissue from a three year old lactating dairy cow (ca. 100 d relative to parturition) was used as a source of the epithelial cell line, which was cultured in collagen-coated tissue culture dishes. Fibroblasts and epithelial cells successively grew and extended from the culturing mammary tissue at the third day. Pure epithelial cells were obtained by passages culture. PRINCIPAL FINDINGS: The strong positive immunostaining to cytokeratin 18 suggested that the resulting cell line exhibited the specific character of epithelial cells. Epithelial cells cultured in the presence of 10% FBS, supraphysiologic concentrations of insulin, and hydrocortisone maintained a normal diploid chromosome modal number of 2n=60. Furthermore, they were capable of synthesizing beta-casein (CSN2), acetyl-CoA carboxylase-alpha (ACACA) and butyrophilin (BTN1A1). An important finding was that frozen preservation in a mixture of 90% FBS and 10% DMSO did not influence the growth characteristics, chromosome number, or protein secretion of the isolated epithelial cell line. CONCLUSIONS: The obtained mammary epithelial cell line had normal morphology, growth characteristics, cytogenetic and secretory characteristics, thus, it might represent an useful tool for studying the function of Chinese Holstein dairy cows mammary epithelial cell (CMECs).


Asunto(s)
Células Epiteliales/citología , Glándulas Mamarias Animales/citología , Animales , Bovinos , Técnicas de Cultivo de Célula/métodos , Línea Celular , Proliferación Celular , China , Colágeno/química , Medios de Cultivo/metabolismo , Femenino , Fibroblastos/citología , Cariotipificación , Queratina-18/biosíntesis
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(5): 1281-5, 2009 May.
Artículo en Chino | MEDLINE | ID: mdl-19650471

RESUMEN

Milk and its products as a kind of ideal comprehensive nutritional food, has becoming an indispensable part of people's daily, life. But at the same time, the quality of dairy products has been also increasingly concerned by consumers. Real-time, rapid and accurate detection of milk and its products in terms of component, adulterants, residues and preservatives is the primary condition for improving the dairy products quality and controlling the production process. Quality predication of milk and its products was often completed by laboratory analysis in the past, which was complicated and time-consuming and could not satisfy the needs for evaluating the milk products quality and monitoring the production proceeding effectively. How to predict the quality of milk and its products quickly and accurately is a practical problem that needs to be resolved. Near-infrared spectroscopy (NIRS) is a rapid, convenient, highly efficient, non-destructive and low-cost analytical technique, which has been widely used in various fields for quantitative and qualitative analysis. As a new analysis technique, NIRS has great potential of application to milk and its products detection, owning to its quick, concise and non--destructive characteristics. The main nutrient components were the major index of milk and its products quality evaluation. Determining the main nutrient components of milk and its products rapidly can provide sound basis for evaluating the products quality. At the same time, adulterants, residues and preservatives were also distinct fingerprint characteristics in the NIR spectra just like the main nutrient components. So this new approaches could also be used in quality distinguishing and on-line detection of milk and its products. Many researches have also concluded that NIRS technology has good stability and high prediction ability on dairy products analysis, exhibites well correlation with the result by labor analysis method. In the present paper, the principles and advantages of NIRS were described. The research advancement of NIRS utilization for milk products nutrient component determination, quality estimation and on-line detection and the application prospect were comprehensively reviewed. With the development of spectral technique, the prediction model gained through NIRS will be more and more reliable and practicable, and the NIRS technique will be more widely used in milk and its products determination, quality estimation and on-line detection.


Asunto(s)
Productos Lácteos Cultivados/química , Análisis de los Alimentos/métodos , Leche/química , Animales , Control de Calidad , Espectrofotometría Infrarroja
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