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1.
Pest Manag Sci ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567786

RESUMEN

BACKGROUND: The important wood-boring pest Batocera horsfieldi has evolved a sensitive olfactory system to locate host plants. Odorant-binding proteins (OBPs) are thought to play key roles in olfactory recognition. Therefore, exploring the physiological function of OBPs could facilitate a better understanding of insect chemical communications. RESULTS: In this research, 36 BhorOBPs genes were identified via transcriptome sequencing of adults' antennae from B. horsfieldi, and most BhorOBPs were predominantly expressed in chemosensory body parts. Through fluorescence competitive binding and fluorescence quenching assays, the antenna-specific BhorOBP28 was investigated and displayed strong binding affinities forming stable complexes with five volatiles, including (+)-α-Pinene, (+)-Limonene, ß-Pinene, (-)-Limonene, and (+)-Longifolene, which could also elicit conformation changes when they were interacting with BhorOBP28. Batocera horsfieldi females exhibited a preference for (-)-Limonene, and a repellent response to (+)-Longifolene. Feeding dsOBP19 produced by a bacteria-expressed system with a newly constructed vector could lead to the knockdown of BhorOBP28, and could further impair B. horsfieldi attraction to (-)-Limonene and repellent activity of (+)-Longifolene. The analysis of site-directed mutagenesis revealed that Leu7, Leu72, and Phe121 play a vital role in selectively binding properties of BhorOBP28. CONCLUSION: By modeling the molecular mechanism of olfactory recognition, these results demonstrate that BhorOBP28 is involved in the chemoreception of B. horsfieldi. The bacterial-expressed dsRNA delivery system gains new insights into potential population management strategies. Through the olfactory process concluded that discovering novel behavioral regulation and environmentally friendly control options for B. horsfieldi in the future. © 2024 Society of Chemical Industry.

2.
Huan Jing Ke Xue ; 44(12): 6495-6507, 2023 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-38098378

RESUMEN

The compositional characteristics, concentration of nitroaromatic compounds(NACs) in PM2.5 in urban Shanghai, and their correlation with gaseous precursors were investigated. A total of 39 winter and 46 summer PM2.5 samples from 2020 to 2021 were collected using a high-flow sampler and analyzed via ultra-performance liquid chromatography coupled with ESI-Orbitrap high-resolution mass spectrometry(UPLC-Orbitrap-HRMS). Quantitative analysis was performed on 12 NACs compounds, combined with backward trajectory meteorological elements, molecular composition, and classification analysis of CHON substances. The results showed that a total of 12 NACs had an average concentration in winter of 17.1 ng·m-3, which was three times higher than that in summer(5.7 ng·m-3), mainly due to air masses in winter coming primarily from the northern part of China with more biomass burning, whereas more air masses in summer came from the cleaner southeastern ocean. 4-Nitrophenol was the most abundant species of NACs in winter, whereas 4-nitrophenol(clean days) and 4-hydroxy-3-nitrobenzoic acid(polluted days) were the most abundant species in summer. Qualitative analysis based on features such as aromatic ring equivalence number(Xc), O/C, and H/C values for the identification and characterization of monocyclic and polycyclic aromatic compounds showed that CHON compounds were mainly aromatic compounds in winter and summer in urban Shanghai. The number and abundance of CHON compounds detected on PM2.5 polluted days were 2 and 1.5 times higher(winter) and 2.5 and 2 times higher(summer) than that on clean days, respectively. Comparing the analysis results of clean and polluted days in winter and summer, it was found that 80% of the CHON compounds with a relative abundance in the top 10 had O/N ≥ 3 and RDBE values between 5 and 8. The results suggest that these highly abundant CHON analogs may have had mononitro- or dinitro-substituted benzene rings. Correlation analysis between gaseous precursors and NACs indicated that oxidative reactive formation of VOCs(benzene, toluene, etc.) from anthropogenic emissions was the main source of NACs in summer. By contrast, it was influenced by a combination of biomass combustion emissions and secondary formation of oxidative NOx from anthropogenic VOCs in winter.

3.
Huan Jing Ke Xue ; 44(11): 5986-5996, 2023 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-37973083

RESUMEN

The characteristics and main factors of causes of haze in Zhoukou in January 2022 were analyzed. Six air pollutants, water-soluble ions, elements, OC, EC, and other parameters in fine particulate matter were monitored and analyzed using a set of online high-time-resolution instruments in an urban area. The results showed that the secondary inorganic aerosols(SNA), carbonaceous aerosols(CA, including organic carbon OC and inorganic carbon EC), and reconstructed crustal materials(CM, such as Al2O3, SiO2, CaO, and Fe2O3, etc.) were the three main components, accounting for 61.3%, 24.3%, and 9.72% in PM2.5, respectively. The concentrations of SNA, CA, CM, and SOA were increased, accompanied with higher AQI. The sulfur oxidation rate(SOR) and nitrogen oxidation rate(NOR) in January were 0.53 and 0.46, respectively. The growth rates[µg·(m3·h)] of sulfate and nitrate were 0.027(-5.89-9.47, range) and 0.051(-23.1-12.4), respectively. During the haze period, the growth rates of sulfate and nitrate were 0.13 µg·(m3·h)-1and 0.24 µg·(m3·h)-1, which were 4.8 and 4.7 times higher than the average value of January, respectively. Although the sulfur oxidation rate was greater than the nitrogen oxidation rate, the growth rate of nitrate was approximately 1.8 times that of sulfate owing to the difference in the concentration of gaseous precursors and the influence of relative humidity. The growth rates of nitrate in SNA were significantly higher than those of sulfate on heavily polluted days. The values of SOR, NOR, and concentrations of SNA and SOA during higher AQI and humidity periods were higher than those in lower AQI and humidity periods. The Ox(NO2+O3) decreased with the increase in relative humidity. The SOA was higher at nighttime, increasing faster with the humidity than that in daytime. Under the situation of lower temperature, higher humidity, and lower wind speed, the emission of gaseous precursors of SNA requires further attention in Zhoukou in winter. Advanced control strategies of emissions of SO2 and NO2, such as mobile sources and coal-burning sources, could reduce the peak of haze in winter efficiently.

4.
Int J Mol Sci ; 24(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36834874

RESUMEN

Natural enemies such as parasitoids and parasites depend on sensitive olfactory to search for their specific hosts. Herbivore-induced plant volatiles (HIPVs) are vital components in providing host information for many natural enemies of herbivores. However, the olfactory-related proteins involved in the recognition of HIPVs are rarely reported. In this study, we established an exhaustive tissue and developmental expression profile of odorant-binding proteins (OBPs) from Dastarcus helophoroides, an essential natural enemy in the forestry ecosystem. Twenty DhelOBPs displayed various expression patterns in different organs and adult physiological states, suggesting a potential involvement in olfactory perception. In silico AlphaFold2-based modeling and molecular docking showed similar binding energies between six DhelOBPs (DhelOBP4, 5, 6, 14, 18, and 20) and HIPVs from Pinus massoniana. While in vitro fluorescence competitive binding assays showed only recombinant DhelOBP4, the most highly expressed in the antennae of emerging adults could bind to HIPVs with high binding affinities. RNAi-mediated behavioral assays indicated that DhelOBP4 was an essential functional protein for D. helophoroides adults recognizing two behaviorally attractive substances: p-cymene and γ-terpinene. Further binding conformation analyses revealed that Phe 54, Val 56, and Phe 71 might be the key binding sites for DhelOBP4 interacting with HIPVs. In conclusion, our results provide an essential molecular basis for the olfactory perception of D. helophoroides and reliable evidence for recognizing the HIPVs of natural enemies from insect OBPs' perspective.


Asunto(s)
Escarabajos , Receptores Odorantes , Animales , Herbivoria , Ecosistema , Simulación del Acoplamiento Molecular , Escarabajos/metabolismo , Receptores Odorantes/metabolismo , Proteínas de Insectos/metabolismo , Antenas de Artrópodos/metabolismo
5.
Phytochem Anal ; 34(2): 209-224, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36529143

RESUMEN

INTRODUCTION: Eleutherococcus senticosus fruit (ESF) is a natural health supplement resource that has been extensively applied as a tonic for the nervous system. The structures and neural bioactivities of triterpenoid saponins (TS), which are the major constituents of ESF, have not been comprehensively analyzed thus far. OBJECTIVE: We conducted a complete in-depth MS/MS molecular networking (MN)-based targeted analysis of TS from the crude extract of ESF and investigated its neuroprotective value. METHODS: An MS/MS MN-guided strategy was used to rapidly present a series of precursor ions (PIs) of TS in a compound cluster as TS-targeted information used in the discovery and characterization of TS. In addition, a prepared TS-rich fraction of ESF was assayed for its restraining effects on ß-amyloid-induced inhibition of neurite outgrowth. RESULTS: A total of 87 TS were discovered using a PI tracking strategy, 28 of which were characterized as potentially undescribed structures according to their high-resolution MS values. Furthermore, the TS-rich fraction can significantly reduce ß-amyloid-induced damage to neural networks by promoting the outgrowth of neurites and axons. CONCLUSION: Our findings reveal the richness of TS in ESF and will accelerate their application in the treatment of neurodegenerative diseases.


Asunto(s)
Eleutherococcus , Saponinas , Triterpenos , Espectrometría de Masas en Tándem , Extractos Vegetales/química , Eleutherococcus/química , Saponinas/química , Frutas/química , Triterpenos/análisis
6.
World J Pediatr ; 19(2): 129-138, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36562929

RESUMEN

BACKGROUND: We aimed to evaluate the tolerability and efficacy of linezolid in children for treating suspected and diagnosed Gram-positive bacterial infections. METHODS: A systematic literature search was conducted up to April 23, 2021, using linezolid and its synonyms as search terms. Two reviewers independently identified and extracted relevant randomized controlled trials and prospective cohort studies. The extracted studies were included in a single-rate meta-analysis of adverse events and clinical outcomes using random-effects models. RESULTS: A total of 1082 articles were identified, and nine studies involving 758 children were included in the meta-analysis. The overall proportion of adverse events was 8.91% [95% confidence interval (CI) = 1.64%-36.52%], with diarrhea (2.24%), vomiting (2.05%), and rash (1.72%) being the most common. The incidences of thrombocytopenia and anemia were 0.68% and 0.16%, respectively. Some specific adverse events, including rash and gastrointestinal events, were more frequent in the oral administration subgroup. In terms of efficacy, the overall proportion of clinical improvement was 88.80% (95% CI = 81.31%-93.52%). Children with a history of specific bacteriological diagnosis or concomitant antibiotic therapy had a 1.13-fold higher clinical improvement than children without such histories. The proportion of microbial eradication was 92.68% (95% CI = 84.66%-96.68%). The proportion of all-cause mortality was 0.16% (95% CI = 0.00%-7.75%). CONCLUSIONS: Linezolid was well-tolerated in pediatric patients and was associated with a low frequency of adverse events, such as anemia, thrombocytopenia, and neutropenia. Moreover, linezolid was effective in children with diagnosed and suspected Gram-positive infections.


Asunto(s)
Antibacterianos , Diarrea , Niño , Humanos , Linezolid/efectos adversos , Estudios Prospectivos , Antibacterianos/efectos adversos , Resultado del Tratamiento
7.
Curr Psychol ; 41(8): 5631-5639, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33046955

RESUMEN

To assess the psychological effects of the novel coronavirus disease (COVID-19) on medical staff and the general public. During the outbreak of COVID-19, an internet-based questionnaire included The Self-rating Depression Scale (SDS), Perceived Stress Scale (PSS-10), and Impact of Event Scale-Revised (IES-R) was used to assess the impact of the pandemic situation on the mental health of medical staff and general population in Wuhan and its surrounding areas. Among the 1493 questionnaires completed, 827 (55.39%) of these were men, and 422 (28.27%) of these were medical personnel. The results suggest that the outbreak of COVID-19 has affected individuals significantly, the degree of which is related to age, sex, occupation and mental illness. There was a significant difference in PSS-10 and IES-R scores between the medical staff and the general population. The medical staff showed higher PSS-10 scores (16.813 ± 4.87) and IES-R scores (22.40 ± 12.12) compared to members of the general population PSS-10 (14.80 ± 5.60) and IES-R scores (17.89 ± 13.08). However, there was no statistically significant difference between the SDS scores of medical staff (44.52 ± 12.36) and the general public (43.08 ± 11.42). In terms of the need for psychological assistance, 50.97% of interviewees responded that they needed psychological counseling, of which medical staff accounted for 65.87% and non-medical staff accounted for 45.10%. During the ongoing COVID-19 outbreak, great attention should be paid to the mental health of the population, especially medical staff, and measures such as psychological intervention should be actively carried out for reducing the psychosocial effects.

8.
Huan Jing Ke Xue ; 42(3): 1298-1305, 2021 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-33742926

RESUMEN

Volatile organic compounds (VOCs) play important roles in the formation of ozone and fine particles in the troposphere. Industrial parks emit significant amounts of VOCs in China, while few studies have characterized them. In the present study, a mobile platform was employed to measure the levels and composition VOCs around industrial parks in the Yangzte River Delta region. The average concentration of VOCs ranged from 39 µg·m-3 (5% percentile) to 533 µg·m-3 (95% percentile) with an average of 183 µg·m-3, which was three times that of ambient concentrations. Maximum VOC concentrations ranged from 307 µg·m-3 (5% percentile) to 12006 µg·m-3 (95% percentile) with an average of 2812 µg·m-3. The frequency of abnormal peak values was as high as 64% across all the industrial parks, of which toluene (32%), xylene (18%), benzene (9%), and>C9 aromatics (19%) were the most common species. Differences in VOC characteristics were observed among the different types of industrial parks. Specifically, highest concentrations of VOCs were observed in textile industrial parks followed by chemical, painting, and petrochemical industrial parks, and VOC concentrations in electronics industrial parks were the lowest. Importantly, species measured using the mobile platform only contributed~50% of VOCs present in ambient samples, indicating that the concentrations of VOCs in the industrial parks were underestimated overall. These results can inform measures to control VOC pollution in industrial parks in China.

9.
Eur J Med Chem ; 187: 111913, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31837501

RESUMEN

In order to produce an effective and multi-targeted clinical drug that could prevent progressive neurodegeneration, a series of diosgenin carbamate derivatives were designed, synthesized and tested for their anti-inflammatory, antioxidant and anti-Aß activities. The results demonstrated that compound M15 was the most promising derivative against inflammatory (NO inhibition 22.7 ± 2.2%,10 µM) and cellular damage induced by H2O2 (SH-SY5Y cell protection = 75.3 ± 3.4%, 10 µM) or Aß (astrocytes protection = 70.2 ± 6.5%, 10 µM). Molecular docking studies revealed the strong binding affinity of M15 to the active site of nNOS, Aß42 and pro-inflammatory proteins. Western blot demonstrated that M15 decreased IL-1ß, IL-6 and TNF-α level, which may contribute to its anti-inflammatory effects. In addition, M15 maintained mitochondrial function as well as cell viability through reducing H2O2-induced ROS production. The results indicated that oral administration of M15 attenuated memory deficits and played a neuroprotective effect on subcutaneous (s.c.) D-gal aging mice. In summary, M15 could be considered as a potential multifunctional neuroprotective agent due to the effects of anti-inflammatory, antioxidant and anti-Aß activities.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antiinflamatorios no Esteroideos/farmacología , Carbamatos/farmacología , Diosgenina/farmacología , Diseño de Fármacos , Fármacos Neuroprotectores/farmacología , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Carbamatos/síntesis química , Carbamatos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Diosgenina/síntesis química , Diosgenina/química , Relación Dosis-Respuesta a Droga , Galactosa/administración & dosificación , Galactosa/farmacología , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Estructura Molecular , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Estrés Oxidativo/efectos de los fármacos , Agregado de Proteínas/efectos de los fármacos , Relación Estructura-Actividad
10.
Eur J Med Chem ; 183: 111717, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31557611

RESUMEN

In our previous study, we reported a series of N-phenylisonicotinamide derivatives as novel xanthine oxidase (XO) inhibitors and identified N-(3-cyano-4-((2-cyanobenzyl)oxy)phenyl)isonicotinamide (compound 1) as the most potent one with an IC50 value of 0.312 µM. To further optimize the structure and improve the potency, a structure-based drug design (SBDD) strategy was performed to construct the missing H-bond between the small molecule and the Asn768 residue of XO. We introduced a tetrazole moiety at the 3'-position of the phenyl to serve as an H-bond acceptor and obtained a series of N-(3-(1H-tetrazol-1-yl)phenyl)isonicotinamide derivatives (2a-t and 6-8). Besides, to investigate the influence of the amide-reversal, some N-(pyridin-4-yl)-3-(1H-tetrazol-1-yl)benzamide derivatives (3c, 3e, 3i, 3k and 3u) were also synthesized and evaluated. Biological evaluation and structure-activity relationship analysis demonstrated that the 3'-(1H-tetrazol-1-yl) moiety was an excellent fragment for the N-phenylisonicotinamide scaffold; a substituted benzyloxy, especially, an m-cyanobenzyloxy (e.g., 2s), linking at the 4'-position was welcome for the potency; and the amide-reversal could damage the potency, so maintenance of the N-phenylisonicotinamide scaffold was essential. In summary, starting from compound 1, the SBDD effort successfully identified a promising XO inhibitor 2s (IC50 = 0.031 µM), with a 10-fold gain in potency. Its potency was very close to the positive control topiroxostat (IC50 = 0.021 µM). A Lineweaver-Burk plot indicated that compound 2s acted as a mixed-type XO inhibitor. Molecular docking and molecular dynamics simulations revealed that the tetrazole moiety could occupy the Asn768-sub-pocket with N-4 atom accepting an H-bond from the Asn768 residue, as expected.


Asunto(s)
Niacinamida/análogos & derivados , Niacinamida/síntesis química , Xantina Oxidasa/antagonistas & inhibidores , Animales , Benzamidas/química , Bovinos , Diseño de Fármacos , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Niacinamida/metabolismo , Nitrilos/metabolismo , Unión Proteica , Piridinas/metabolismo , Relación Estructura-Actividad , Tetrazoles/química , Ácido Úrico/metabolismo , Xantina Oxidasa/metabolismo
11.
J Gastroenterol Hepatol ; 33(4): 869-877, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29073345

RESUMEN

BACKGROUND AND AIM: The Chinese version quality of life questionnaire for functional digestive disorders (Chin-FDDQL) is a useful health assessment instrument for functional dyspepsia. This study aims to identify its score interpretation for clinical practice. METHODS: Data of Chin-FDDQL from the functional dyspepsia patients (≥ 18 years) between November 2009 and April 2013 were enrolled in the 1st and 14th day. After baseline and responsiveness analysis, the single score interpretation and percentile ranks were established. The statistically reliable change was defined with effect size, standardized response mean, minimal detectable change, and others. Then the receiver operating characteristic curve analysis for health improvement was performed to define the clinically important change. RESULTS: Two hundred two functional dyspepsia patients, 150 healthy participants, and 25 missing data were enrolled for analysis. Compared with the intake patients, the discharged and healthy persons have significant better health status in all domains (P < 0.001, expect discomfort in discharged people, P = 0.142), totally contrast to missing data. The reliability for single total intake and discharge were both ± 1. Based on score distribution, the 25th, 50th, and 75th percentile ranks were 49, 58, and 66 for intake scores and 59, 65, and 72 for discharge scores, respectively. The minimal detectable change and Reliable Change Index were 6 and 11 for total score. Receiver operating characteristic analyses supported that total score changes 4 or more represented minimal clinically important improvement. CONCLUSIONS: The score interpretation system of the Chin-FDDQL could assist clinician's decision making during the therapy practice.


Asunto(s)
Dispepsia/fisiopatología , Dispepsia/psicología , Lenguaje , Calidad de Vida , Encuestas y Cuestionarios , Adolescente , Adulto , China , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Curva ROC
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 765-9, 2016 Mar.
Artículo en Chino | MEDLINE | ID: mdl-27400521

RESUMEN

Cytisine (Cy) is one of the alkaloids that exist naturally in the plant genera Laburnum of the family Fabaceae. With strong bioactivities, Cy is commercialized for smoking cessation for years. In this work, the study of intermolecular interactions between Cy and bovine serum albumin (BSA) was performed by applying fluorescence spectroscopic methods under simulated physiological conditions. The mechanism of fluorescence quenching of BSA by Cy was also studied. Parameters such as bathing temperature, time and solution pH were investigated to optimize the fluorescence quenching. The binding type, binding ratio and binding constant between BSA and Cy were calculated by using the Stem-Volmer equation. Experimental results indicated that Cy can quench the fluorescent emission of BSA statically by forming a 1 : 1 type non-covalent complex and the binding constant is 5.6 x 10(3) L x mol(-1). Synchronous fluorescence spectral research shows Cy may affect the fluorescence emission of Trp residues of BSA. Furthermore, molecular docking is utilized to model the complex and probe the plausible quenching mechanism. It can be noted that the hydrogen bindings and hydrophobic interactions between Cy and BSA change the micro-environment of Trp213, which leads to the fluorescence quenching of BSA.


Asunto(s)
Alcaloides/química , Simulación del Acoplamiento Molecular , Albúmina Sérica Bovina/química , Espectrometría de Fluorescencia , Azocinas/química , Interacciones Hidrofóbicas e Hidrofílicas , Quinolizinas/química
13.
J Phys Chem B ; 120(6): 1121-5, 2016 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-26815575

RESUMEN

Electric-assisted capillary rise adsorption of polar and nonpolar solvents by cellulose and chitosan was studied by employing an electrostatic generator to assist a common capillary rise wetting by taking the anode and cathode electrodes respectively linked to a metal tube charged with samples and the probe solvent. To vary the voltage at 0, 100, 200, and 300 V, respectively, the recorded dynamic adsorption results showed that the cellulose and chitosan both kept a stable adsorption of the nonpolar hexane and diiodomethane, obviously ignoring the voltage increase. Moreover, the hexane amount adsorbed by cellulose and chitosan is similar, while the diiodomethane amount was adsorbed to a greater amount by cellulose as compared with the chitosan corresponding to these two biomaterials-based nonpolar components, for example, greater for cellulose and smaller for chitosan. Results also showed that the adsorption of polar water and formamide was gradually increased with the voltage increase, especially for chitosan, to correspond to the polar component of these materials, for example, greater for chitosan and smaller for cellulose. These adsorption behaviors suggested that the application of an extra electric field can only enhance the adsorption of polar solvent, and the molecular structure, for exmaple, the ß-(1-4)-linked d-glucosamine units of chitosan, has sensitive electric field responses in polar solvent adsorption as compared with those of the ß(1-4)-linked d-glucose units of cellulose. The reason for the electric adsorption behaviors was known due to the presence of an extra electric-field-induced reduction of the total surface tension of solvent and mainly the polar component.


Asunto(s)
Celulosa/química , Quitosano/química , Electricidad , Solventes/química , Electricidad Estática , Adsorción , Electrodos , Propiedades de Superficie
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(4): 739-42, 2007 Apr.
Artículo en Chino | MEDLINE | ID: mdl-17608187

RESUMEN

Retrieval of ground reflectance spectrum from satellite sensor digital count requires knowledge of the atmospheric conditions. Images of spectral radiance from ground-atmosphere system recorded by the multi-spectral imager ETM which boarded Landsat-7 sensor can retrieve the ground reflectivity spectrum. The uncertainty of reflectance spectrum retrieval is no more than 17% at the band 1 of ETM, and less than 10% at the band 2 and 3 of ETM. It is superior to those arithmetics widely used at present. Retrieval of ground radiance spectrum from ground-atmosphere system can be used to synthesize the sRGB true color image, but the definition is not excellent. And it was proved that the color of the images can not reflect the actual nature of earth objects before being adjusted. And the accuracy of interpretation based on true color synthesized images is superior to those based on the source images. So the precision of such reflectance spectrum retrieval is not as good as expected if applied to the true color photography on the ground.

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