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1.
Sci Total Environ ; 920: 170943, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38365029

RESUMEN

Thaliaceans are globally distributed and play an important role in the world's biological carbon pump and marine ecosystems by forming dense swarms with high feeding rates and producing large amounts of fecal pellets and carcasses. The contribution of thaliacean swarms to the downward transport of carbon depends not only on their abundance but also on their body size. However, the key factors influencing the distribution of different-sized thaliaceans remain unstudied. To discriminate thaliacean assemblages and examine the key factors determining the zoogeographical distribution and abundance of different-sized thaliaceans during different monsoon periods, we conducted three cruises in the South China Sea from before the southwest monsoon to the peak of the northeast monsoon. Our results revealed that high thaliacean abundance corresponded to high chlorophyll a concentration, which were associated with hydrodynamic processes, such as upwelling and eddies. Hierarchical partitioning and niche difference analyses demonstrated that current velocity and temperature are key factors that shaped the zoogeographical distribution of different-sized thaliaceans. The global dataset indicated that small-sized thaliacean species tend to occur in coastal areas where the current velocity is generally high, while large-sized species tend to occur in open ocean areas where the current velocity is generally low. The results revealed that global warming-induced changes in surface current velocity and temperature may alter the zoogeographical distribution and abundance of thaliaceans with different sizes, thereby affecting the biological carbon pump and surrounding marine ecosystem. Overall, this study sheds light on the potential responses of pelagic tunicates to global climate change through changes in their hydrodynamic conditions.


Asunto(s)
Cambio Climático , Ecosistema , Temperatura , Clorofila A , Carbono
2.
Materials (Basel) ; 15(12)2022 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-35744368

RESUMEN

Realizing the green recycling of sludge is an important link to effectively solve the problem of sludge disposal. In this paper, sewage sludge (SS) and rice husk (RH) were utilized as raw materials in preparing novel ceramsite (SRC) for the treatment of lead-containing wastewater, and its adsorption mechanism was explored. The results showed that the optimal preparation conditions were 40% RH + 60% SS mixture, a sintering temperature of 1190 °C, and a sintering time of 20 min. The basic properties of SRC met Chinese artificial ceramsite filter material standards for water treatment (CJ/T 299-2008). Under optimum adsorption conditions (pH = 6, 1 g/L SRC dosage, 20 mg/L Pb(NO)3 concentration, 18 h), the removal rate of Pb2+ reached 94.7%, and the equilibrium adsorption capacity was 18.94 mg/g. The adsorption process was more consistent with the pseudo-second-order kinetic model and the Langmuir isotherm model, indicating that the adsorption process was dominated by chemisorption. Thermodynamic parameters (ΔH0 > 0, ΔG0 < 0, ΔS0 > 0) indicated that the adsorption reaction was spontaneous and endothermic. The possible adsorption mechanisms are as follows: (1) SRC is rich in layered mesoporous structure, which provides sufficient reaction sites for Pb adsorption; (2) the sintered lawsonite and muscovite can strongly attract Pb and then form a new phase (Pb10[Si2O7]3(OH)2); (3) Pb2+ can bond with the Si−O- bond in aluminosilicates, and the introduction of Pb elevates the degree of polymerization of aluminosilicates in turn, indicating that the adsorption process is stable.

3.
PLoS One ; 17(6): e0267434, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35648775

RESUMEN

A hybrid model integrating chaos theory, support vector machine (SVM) and the difference evolution grey wolf optimization (DEGWO) algorithm is developed to analyze and predict dam deformation. Firstly, the chaotic characteristics of the dam deformation time series will be identified, mainly using the Lyapunov exponent method, the correlation dimension method and the kolmogorov entropy method. Secondly, the hybrid model is established for dam deformation forecasting. Taking SVM as the core, the deformation time series is reconstructed in phase space to determine the input variables of SVM, and the GWO algorithm is improved to realize the optimization of SVM parameters. Prior to this, the effectiveness of DEGWO algorithm based on the fusion of the difference evolution (DE) and GWO algorithm has been verified by 15 sets of test functions in CEC 2005. Finally, take the actual monitoring displacement of Jinping I super-high arch dam as examples. The engineering application examples show that the PSR-SVM-DEGWO model established performs better in terms of fitting and prediction accuracy compared with existing models.


Asunto(s)
Algoritmos , Máquina de Vectores de Soporte , Predicción , Dinámicas no Lineales
4.
Biomed Chromatogr ; 34(6): e4821, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32150287

RESUMEN

Polygoni multiflori Radix Praeparata (PMRP) is a traditional medicine used for nourishing essence and blood in China. However, it is unclear which PMRP compounds are responsible for its hematopoietic effect. In this study, spectrum-effect relationship was used to discovery potential hematopoietic compounds. The fingerprints of 20 PMRP batches were established by HPLC and the hematopoietic effect was determined using red blood cell, hemoglobin, hematocrit, and platelet indexes in aplastic anemia model mice. The spectrum-effect relationship between common peaks and hematopoietic efficacy values was established using gray relational analysis and partial least squares analysis. Spectrum-effect relationship results showed that peaks 21 (emodin-8-O-(6´-O-acetyl)-ß-D-glucoside), 15 (2, 3, 5, 4'-tetrahydroxystilbene-2-O-di-glucoside), 16 (cis-2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-D-glucoside), 11 (unknown), 20(unknown, 12 (epicatechin), 29 (carboxyl emodin), and 31 (emodin) in the fingerprints were closely related to the hematopoietic effect. This work successfully established the spectrum-effect relationship between PMRP hematopoietic effect and its fingerprints, which can be used to explain the material basis for the PMRP hematopoietic effect.


Asunto(s)
Medicamentos Herbarios Chinos , Hematínicos , Anemia Aplásica , Animales , Recuento de Células , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Eritrocitos/efectos de los fármacos , Hematínicos/análisis , Hematínicos/química , Hematínicos/farmacología , Pruebas Hematológicas , Hemoglobinas/análisis , Masculino , Ratones , Ratones Endogámicos ICR
5.
Sci Rep ; 7(1): 11883, 2017 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-28928429

RESUMEN

Early brain injury (EBI) is involved in the process of cerebral tissue damage caused by subarachnoid hemorrhage (SAH), and multiple mechanisms, such as apoptosis and inflammation, participate in its development. Mangiferin (MF), a natural C-glucoside xanthone, has been reported to exert beneficial effects against several types of organ injury by influencing various biological progresses. The current study aimed to investigate the potential of MF to protect against EBI following SAH via histological and biological assessments. A rat perforation model of SAH was established, and MF was subsequently administered via intraperitoneal injection at a low and a high dose. High-dose MF significantly lowered the mortality of SAH animals and ameliorated their neurological deficits and brain edema. MF also dose-relatedly attenuated SAH-induced oxidative stress and decreased cortical cell apoptosis by influencing mitochondria-apoptotic proteins. In addition, MF downregulated the activation of the NLRP3 inflammasome and NF-κB as well as the production of inflammatory cytokines, and the expression of Nrf2 and HO-1 was upregulated by MF. The abovementioned findings indicate that MF is neuroprotective against EBI after SAH and Nrf2/HO-1 cascade may play a key role in mediating its effect through regulation of the mitochondrial apoptosis pathway and activation of the NLRP3 inflammasome and NF-κB.


Asunto(s)
Apoptosis/efectos de los fármacos , Lesiones Encefálicas , Hemo Oxigenasa (Desciclizante)/metabolismo , Mitocondrias/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Hemorragia Subaracnoidea , Xantonas/farmacología , Animales , Lesiones Encefálicas/tratamiento farmacológico , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Masculino , Mitocondrias/patología , Ratas , Ratas Sprague-Dawley , Hemorragia Subaracnoidea/tratamiento farmacológico , Hemorragia Subaracnoidea/metabolismo , Hemorragia Subaracnoidea/patología
6.
Sensors (Basel) ; 17(9)2017 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-28837096

RESUMEN

The purpose of this study was to develop a robust, fast and markerless mobile augmented reality method for registration, geovisualization and interaction in uncontrolled outdoor environments. We propose a lightweight deep-learning-based object detection approach for mobile or embedded devices; the vision-based detection results of this approach are combined with spatial relationships by means of the host device's built-in Global Positioning System receiver, Inertial Measurement Unit and magnetometer. Virtual objects generated based on geospatial information are precisely registered in the real world, and an interaction method based on touch gestures is implemented. The entire method is independent of the network to ensure robustness to poor signal conditions. A prototype system was developed and tested on the Wuhan University campus to evaluate the method and validate its results. The findings demonstrate that our method achieves a high detection accuracy, stable geovisualization results and interaction.

7.
Theranostics ; 7(3): 764-774, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28255365

RESUMEN

Protein nanoparticles as nanocarriers are of particular interest in the field of cancer therapy. Nevertheless, so far a facile fabrication of theranostic protein nanoparticles have been explored with limited success for cancer imaging and therapy. In this work, we demonstrate the controllable synthesis of size-tunable Gd2O3@albumin conjugating photosensitizer (PS) (GA-NPs) using hollow albumin as the nanoreactor for magnetic resonance imaging (MRI)-guided photo-induced therapy. The growth of Gd2O3 nanocrystals within the hollow nanoreactors is well regulated through reaction time, and a typical PS (e.g. chlorin e6) is further conjugated with the protein corona of the nanoreactor through facile chemical coupling, followed by the formation of theranostic GA-NPs. GA-NPs exhibit good longitudinal relaxivity, ideal photostability, enhanced cellular uptakes, and preferable size-dependent tumor accumulation. Moreover, GA-NPs effectively generate remarkable photothermal effect, intracellular reactive oxygen species from Ce6, and subsequent cytoplasmic drug translocation, thereby leading to severe synergistic photothermal and photodynamic cell damages. Consequently, GA-NPs exhibit an in vivo size-dependent MRI capacity with enhanced imaging contrast for effective tumor localization, and also generate a potent synergistic photodynamic therapy/photothermal therapy efficacy under irradiation owing to their enhanced tumor accumulation and strong photo-induced cytotoxicity. These results suggest that GA-NPs can act as a promising theranostic protein nanoplatform for cancer imaging and photo-induced therapy.


Asunto(s)
Albúminas/administración & dosificación , Gadolinio/administración & dosificación , Imagen por Resonancia Magnética/métodos , Nanopartículas/administración & dosificación , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Porfirinas/administración & dosificación , Animales , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Clorofilidas , Hipertermia Inducida/métodos , Ratones , Nanomedicina Teranóstica/métodos , Resultado del Tratamiento
8.
Mar Pollut Bull ; 112(1-2): 123-133, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27539638

RESUMEN

Nutrient concentration and phytoplankton biomass were investigated in Huangyan Atoll in May 2015. The concentrations of nutrients were very low, and dissolved inorganic nitrogen was composed mainly of ammonia. Nitrogen likely was the primary limiting factor for phytoplankton growth. The spatial variation of phytoplankton biomass was significant among the lagoon, reef flats, and outer reef slopes. Extremely high chlorophyll a concentration and micro-phytoplankton abundance were found in the region near the lagoon mouth. This high phytoplankton biomass might be due to nutrient input from fishing vessels and phytoplankton aggregation driven by the southwestern wind. Our results indicate that phytoplankton biomass could be a reliable indicator of habitat differences in this coral reef ecosystem, and micro-phytoplankton seems to be more sensitive to nutrient input than pico-phytoplankton.


Asunto(s)
Biomasa , Arrecifes de Coral , Monitoreo del Ambiente , Fitoplancton/crecimiento & desarrollo , China , Clorofila/análisis , Clorofila A , Ecosistema , Nitrógeno/análisis , Viento
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1949-53, 2016 Jun.
Artículo en Chino | MEDLINE | ID: mdl-30053359

RESUMEN

The spectrum of optical fiber surface plasmon resonance (SPR) shows the characteristics of wider full width at half-maximum (FWHM) and smaller peak value. The traditional peak detection algorithm cannot calculate the resonance wavelength of this kind of spectrum accurately. Therefore, efficient methods to calculate the resonance wavelength are required. This paper presents a method to process the SPR signal based on the Gaussian fitting. Combined with the trust region algorithm to determine the Gaussian fitting function, and then the resonance wavelength be calculated by line search method. Data processing of standard spectrum of glycerin with different concentration proves that this algorithm can adapt to optical fiber SPR spectrum characteristics, and calculate resonance wavelength accurately. The experiment measures the SPR signals of sucrose under different concentrations through the self-building SPR measure system. By using the proposed method, the weighted centroid method and the tracking centroid method to calculate the resonance wavelength, the result shows that the Gaussian fitting method can effectively improve resolution and have a short operation time which is conducive to engineering application.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1124-8, 2015 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-26197615

RESUMEN

The spectrum of surface plasmon resonance shows different amplitudes and peak widths with theeffects of resonant intensity and position, so it's necessary to develop the self-adaptive methods to guarantee the accurate positioning of SPR formant. Based on the optimized Savitzky-Golay filter, this paper presents a method for SPR spectrum, which can optimize the parameters (polynomial degree and window size) according to the characteristics of the real time SPR spectrum, and minimizes the Stein's unbiased risk estimate of the mean squared error, and it can be quickly solved by Monte-Carlo methods. It is confirmed that SURE can accurately reflect the trends and the results of the true MSE. The experiment measures the SPR signals of sucrose under different concentrations and integration time through the SPR system. By using the proposed method of optimal parameters on the SPR signal filtering, the results show that the repeatability error of the position of SPR formant is smaller compared with the fixed parameters, and does not increase with the addition of noise levels.

11.
Artículo en Inglés | MEDLINE | ID: mdl-26099823

RESUMEN

A chemosensor consisting of two terpyridines covalently linked to a dithienosilole unit (1) has been synthesized, and its optical and metal sensing properties have been investigated. Due to the metal-organic coordination function, 1 can bind with many transition metal ions and display different fluorescence responses that cause it to function as a "turn-off" fluorescent chemosensor. A significant bathochromic shift in the fluorescence spectra is observed in the presence of Zn(2+). Meanwhile, the emission of 1 is weakened upon exposure to Ag(+) and Fe(2+) and completely quenched by Ni(2+), Co(2+), and Cu(2+). Based on the observed results, several logic gates, such as XNOR, INHIBIT, and IMPLICATION, have been achieved by controlling the chemical inputs.

12.
ScientificWorldJournal ; 2014: 535768, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25610908

RESUMEN

Here the spatial distribution of soil enzymatic properties in agricultural land was evaluated on a county-wide (567 km(2)) scale in Changwu, Shaanxi Province, China. The spatial variations in activities of five hydrolytic enzymes were examined using geostatistical methods. The relationships between soil enzyme activities and other soil properties were evaluated using both an integrated total enzyme activity index (TEI) and the geometric mean of enzyme activities (GME). At the county scale, soil invertase, phosphatase, and catalase activities were moderately spatially correlated, whereas urease and dehydrogenase activities were weakly spatially correlated. Correlation analysis showed that both TEI and GME were better correlated with selected soil physicochemical properties than single enzyme activities. Multivariate regression analysis showed that soil OM content had the strongest positive effect while soil pH had a negative effect on the two enzyme activity indices. In addition, total phosphorous content had a positive effect on TEI and GME in orchard soils, whereas alkali-hydrolyzable nitrogen and available potassium contents, respectively, had negative and positive effects on these two enzyme indices in cropland soils. The results indicate that land use changes strongly affect soil enzyme activities in agricultural land, where TEI provides a sensitive biological indicator for soil quality.


Asunto(s)
Enzimas/análisis , Suelo/química , China , Jardinería , Nitrógeno/análisis , Fósforo/análisis , Potasio/análisis , Control de Calidad , Suelo/normas
13.
Peptides ; 50: 8-12, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24120704

RESUMEN

Visfatin is linked to inflammation and associated with clinical outcomes of intracerebral hemorrhage. This study was designed to investigate whether visfatin might serve as a marker of severity and prognosis in aneurysmal subarachnoid hemorrhage. In this study, plasma visfatin levels of 172 consecutive patients and 172 sex and age-matched healthy subjects were determined using enzyme-linked immunosorbent assay. The recorded clinical outcomes included in-hospital mortality and 6-month mortality and unfavorable outcome (Glasgow Outcome Scale score of 1-3). Plasma visfatin level was substantially higher in patients than in healthy controls (92.1 ± 20.5 ng/mL vs. 12.4 ± 3.2 ng/mL; P<0.001), was significantly associated with the World Federation of Neurological Surgeons (WFNS) score (r=0.569, P<0.001) and Fisher score (r=0.657, P<0.001), was an independent predictor of in-hospital mortality [odds ratio (OR), 1.378; 95% confidence interval (CI), 1.036-1.866; P=0.002] and 6-month mortality (OR, 1.261; 95% CI, 1.018-1.745; P=0.004) and unfavorable outcome (OR, 1.207; 95% CI, 1.012-1.682; P=0.008) in multivariate logistic regression analysis and had high predictive value for in-hospital mortality [area under curve (AUC), 0.849; 95% CI, 0.787-0.899; P<0.001] and 6-month mortality (AUC, 0.868; 95% CI, 0.808-0.915; P<0.001) and unfavorable outcome (AUC, 0.859; 95% CI, 0.797-0.907; P<0.001) using receiver operating characteristic curves. AUCs of visfatin were similar to those of WFNS score and Fisher score (all P>0.05), but visfatin did not improve the predictive values of WFNS score and Fisher score (all P>0.05). Thus, visfatin may be associated with clinical severity of aneurysmal subarachnoid hemorrhage and also have prognostic value for clinical outcomes.


Asunto(s)
Citocinas/sangre , Aneurisma Intracraneal/sangre , Nicotinamida Fosforribosiltransferasa/sangre , Hemorragia Subaracnoidea/sangre , Adolescente , Adulto , Anciano , Área Bajo la Curva , Biomarcadores/sangre , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Escala de Consecuencias de Glasgow , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/etiología , Hemorragia Subaracnoidea/mortalidad , Análisis de Supervivencia
14.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 19(6): 336-9, 2007 Jun.
Artículo en Chino | MEDLINE | ID: mdl-17577437

RESUMEN

OBJECTIVE: To investigate the expression and significance of matrix metalloproteinase-2 (MMP-2) and MMP-9 in peri-hematoma brain tissues after acute brain hemorrhage in human. METHODS: Forty-two patients with acute brain hemorrhage received surgery, the brain tissues adjacent to hemorrhagic site were obtained during surgery, and positive expressions of MMP-2 and MMP-9 were determined with immunohistochemical staining. Brain tissues from 30 patients with cerebral trauma were obtained to serve as controls. RESULTS: The positive expressions of MMP-2 and MMP-9 in focal brain tissues were significantly elevated in early acute brain hemorrhage. Compared with 28 and 27 cases with MMP-2 and MMP-9 positive expression respectively in control group, there were 39 and 37 cases with MMP-2 and MMP-9 positive expression respectively in acute brain hemorrhage group. There were no significant differences between two groups (both P>0.05). CONCLUSION: MMP-2 and MMP-9 might contribute to brain edema formation in the acute intra-cerebral hemorrhage of human.


Asunto(s)
Encéfalo/enzimología , Hemorragia Cerebral/enzimología , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
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