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1.
Sensors (Basel) ; 19(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939813

RESUMO

A grey wolf optimization-based track-before-detect (GWO-TBD) method is developed for extended target detection and tracking. The aim of the GWO-TBD is tracking weak and maneuvering extended targets in a cluttered environment using the measurement points of an air surveillance radar. The optimal solution is the trajectory constituted by the points of an extended target. At the beginning of the GWO-TBD, the measurements of each scan are clustered into alternative sets. Secondly, closely sets are associated for tracklets. Each tracklet equals a candidate solution. Thirdly, the tracklets are further associated iteratively to find a better solution. An improved GWO algorithm is developed in the iteration for removal of unappreciated solution and acceleration of convergence. After the iteration of several generations, the optimal solution can be achieved, i.e. trajectory of an extended target. Both the real data and synthetic data are performed with the GWO-TBD and several existing algorithms in this work. Result infers that the GWO-TBD is superior to the others in detecting and tracking maneuvering targets. Meanwhile, much less prior information is necessary in the GWO-TBD. It makes the approach is engineering friendly.


Assuntos
Algoritmos , Aeronaves , Sistemas de Informação Geográfica , Método de Monte Carlo , Radar
2.
Yao Xue Xue Bao ; 50(2): 191-8, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25975027

RESUMO

A series of [1,3]dioxolo[4,5-f]isoindolone derivatives were designed, synthesized and evaluated as inhibitors of acetylcholinesterases (AChE). Furthermore, their effects on memory impairment of mice induced by scopolamine were investigated with step-through test. The results suggested that most of the target compounds exhibited potential inhibition on AChE with IC50 values at micromolar range. Compounds I1 (IC50 value of 0.086 µmol · L(-1)) and I2 (IC50 value of 0.080 µmol · L(-1)) showed the strongest AChE inhibitory activity, which are equipotent to donepezil (IC50 value of 0.094 µmol · L(-1)). Moreover, compounds I1-I4 could improve the memory impairment induced by scopolamine in mice.


Assuntos
Inibidores da Colinesterase/química , Dioxóis/síntese química , Desenho de Fármacos , Isoindóis/química , Isoindóis/síntese química , Animais , Inibidores da Colinesterase/síntese química , Dioxóis/química , Donepezila , Indanos , Concentração Inibidora 50 , Transtornos da Memória/tratamento farmacológico , Camundongos , Piperidinas , Escopolamina
3.
Yao Xue Xue Bao ; 49(8): 1143-9, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25322556

RESUMO

A series of novel 4-substituted-3-nitrobenzamide derivatives were designed and synthesized. The structures of the target compounds were confirmed with 1H NMR, 13C NMR, MS and element analysis. Anti-tumor activities against HCT-116, MDA-MB435 and HL-60 cell lines in vitro were evaluated by SRB assay. The results indicated most of the target compounds exhibited potent anti-tumor activity. Compound 4a showed the most potent inhibitory activities against three cancer cell lines with the GI50 values of 1.904-2.111 micromol x L(-1). Compounds 4g, 41-4n exhibited more potent inhibitory activities against MDA-MB435 and HL-60 cell lines with the GI50 values of 1.008-3.586 micromol x L(-1) and 1.993-3.778 micromol x L(-1), respectively. The structure-activity relationship of these compounds is discussed preliminarily.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Antineoplásicos/síntese química , Benzamidas/síntese química , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Células HL-60 , Humanos , Concentração Inibidora 50 , Relação Estrutura-Atividade
4.
J Chromatogr A ; 1635: 461765, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285418

RESUMO

In the design of highly ordered (covalent organic frameworks) COFs with "ordered domains size and orientation" construction in a well-defined arrangement, the molecular monomers are the key factors. Here, the effect of molecular monomers on the construction of COFs has been studied, and two kinds of molecular monomers, i.e., ethanediamine (flexible amine ligand) and 4,4'-diaminobiphenyl (rigid amine ligand) have been used for developing sheet-like COFs-I and sheet-like COFs-II, respectively. Furthermore, they have been evaluated in the dispersive solid phase extraction (dSPE) procedure for textiles prior to the analysis of alkylphenol by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). The results showed that, the optimal usage amount of sheet-like COFs-II used in the dSPE procedure was less than that of sheet-like COFs-I, which may be explained by much higher adsorption capacity of sheet-like COFs via hydrogen-bonding and π-π stacking interactions. Rectilinear calibration graphs were obtained for 4-(tert-octyl)-phenol (4-tOP) and 4-nonylphenol (4-NP) in the range 0.2-20 µg/kg with determination coefficient (r2) higher than 0.9990, and the limits of detection (LODs) of 4-tOP and 4-NP were 0.039 µg/kg and 0.048 µg/kg, respectively. The developed method has been successfully applied to analysis of 50 textile samples, in which 4-tOP and 4-NP were found in six samples with concentrations in the range of 1.6 µg/kg-20.9 µg/kg.


Assuntos
Técnicas de Química Analítica/métodos , Estruturas Metalorgânicas/química , Fenóis/isolamento & purificação , Têxteis , Adsorção , Cromatografia Líquida , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas em Tandem
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(11): 2927-31, 2010 Nov.
Artigo em Zh | MEDLINE | ID: mdl-21284155

RESUMO

Olinda valencia orange leaves dry powder-like were taken as sample, and chemical analysis combined with technology of visible near-infrared spectroscopy (Vis/NIRS) was used, through the treatment process of second derivative spectrum of samples of the original spectrum and denoising (Noise). Meanwhile, method of partial least squares (PLS) and cross-validation were used to establish maths model of Zn concentration which applying band combination composited by 400-500 and 1201-1300 nm of characteristic wavelength band. The coefficient of establishing models is 0.9975, while the coefficient of correlation coefficient of prediction is 0.9920. The root mean square error of prediction (RMSEP) of cross-validation is 0.5868. Therefore, the means using visible near-infrared spectroscopy (Vis/NIRS) and the methods of cross-validation and PLS to establish the spectral correction model reflecting the Zn content in leaves and characteristic wavelength bands can detect the Zn content in citrus leaves quantitatively and quickly.


Assuntos
Citrus sinensis/química , Folhas de Planta/química , Espectroscopia de Luz Próxima ao Infravermelho , Zinco/análise
6.
Front Pharmacol ; 10: 370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057403

RESUMO

Tumor cell migration is a critical step in cancer metastasis. Over-activated Notch pathway can promote the migration of cancer cells, especially in the breast cancer. However, the underlying mechanism of non-canonical Notch signaling in modulating the migration has not yet been clearly characterized. Here we demonstrated that DAPT, a gamma secretase inhibitor, inhibited protrusion formation and cell motility, and then reduced the migration of triple-negative breast cancer cells, through increasing the activity of Cdc42 by non-canonical Notch pathway. Phosphorylation of AKT on S473 was surprisingly increased when Notch signaling was inhibited by DAPT. Inhibition of PI3K and AKT by LY294002 and MK2206, respectively, or knockdown of AKT expression by siRNA blocked DAPT-induced activation of Cdc42. Moreover, immunofluorescence staining further showed that DAPT treatment reduced the formation of lamellipodia and induced actin cytoskeleton remodeling. Taken together, these results indicated that DAPT inhibited Notch signaling and consequently activated PI3K/AKT/Cdc42 signaling by non-canonical pathway, facilitated the formation of filopodia and inhibited the assembly of lamellipodia, and finally resulted in the decrease of migration activity of breast cancer cells.

7.
Nanoscale ; 5(17): 7906-12, 2013 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-23851378

RESUMO

A Fe2O3@NiO core/shell nanorod array on carbon cloth was prepared with the aid of hydrothermal synthesis combined with subsequent chemical bath deposition. The resultant array structure is composed of Fe2O3 nanorods as the core and interconnected ultrathin NiO nanoflakes as the shell. As an anode material for lithium-ion batteries, the heterostructured array electrode delivers a high discharge capacity of 1047.2 mA h g(-1) after 50 cycles at 200 mA g(-1), and 783.3 mA h g(-1) at a high current density of 2000 mA g(-1). The excellent electrochemical performance is attributed to the unique 3D core/shell nanorod array architecture and a rational combination of two electrochemical active materials. Our growth approach offers a simple and effective technique for the design and synthesis of a transition metal oxide hierarchical array that is promising for high-performance electrochemical energy storage.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Compostos Férricos/química , Lítio/química , Nanotubos/química , Níquel/química , Técnicas Eletroquímicas , Eletrodos
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