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1.
Appl Opt ; 63(8): 2011-2019, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568642

RESUMO

In the field of optical fiber vibration signal recognition, one-dimensional signals have few features. People often used the shallow layer of a one-dimensional convolutional neural network (1D-CNN), which results in fewer features being learned by the network, leading to a poor recognition rate. There are also many complex algorithms and data processing methods, which make the whole signal recognition process more complicated. Therefore, an optical vibration signal recognition method based on an efficient multidimensional feature extraction network was proposed. Based on ResNet-50, efficient channel attention (ECA) was used to improve image features extraction ability, and a long short-term memory (LSTM) network was used to enhance the extraction of temporal features. Three different vibration signals were collected using a phase-sensitive optical time-domain reflectometry (Φ-OTDR) optical fiber sensing system. Vibration signals were converted into 128×128 grayscale images, which have more effective vibration information. The experimental results show that the three types of signals can be recognized and classified effectively by the network, and the average recognition rate is 98.67%.

2.
Pest Manag Sci ; 79(12): 5283-5291, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37615248

RESUMO

BACKGROUND: Fertilizers and pesticides are commonly used simultaneously in agriculture. However, the effects of common fertilizers on the dissipation, enantioselectivity, and metabolites of the chiral insecticide fipronil in soil are yet to be reported. RESULT: An enantioselective method for detecting fipronil enantiomers and their metabolites in different soil matrices was developed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that organic and compound fertilizers significantly decreased the degradation of S- and R-fipronil, whereas phosphate and microbial fertilizers slightly reduced fipronil dissipation. The half-life values for S- and R-fipronil were 43.3 and 28.9 days, 99.0 and 63.0 days, 69.3 and 43.3 days, 46.2 and 30.1 days, and 43.3 and 31.5 days, respectively, in the control and the four fertilizer treatments, respectively. The enantioselectivity of fipronil enantiomers occurred and R-fipronil exhibited preferential degradation with an enantiomeric fraction (EF) of 0.4900-0.6238 in all treatments; but the four tested fertilizers decreased enantioselectivity with EF values changed from 0.4970 to 0.6238 in the control to 0.4900-0.6171 in fertilizer treatments. Two metabolites, fipronil sulfone and sulfide, were produced, and their amounts increased with culture time in all treatments. Fertilization reduced the content of fipronil sulfide and sulfone but hardly reduced the total amount of fipronil and its metabolites. CONCLUSION: Fertilizers affect the environmental behavior of fipronil in the soil. Fertilization alters the soil bacterial community, which may be an important factor. This influence is relatively complicated and should be comprehensively considered in the environmental risk assessment of pesticides. © 2023 Society of Chemical Industry.


Assuntos
Praguicidas , Pirazóis , Solo , Solo/química , Fertilizantes , Cromatografia Líquida , Espectrometria de Massas em Tandem , Sulfetos , Fertilização
3.
Appl Opt ; 62(3): 697-705, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821274

RESUMO

Images are one of the important sources of getting information, and the process of getting images can be affected by various factors. Atmospheric turbulence is one of them. Ghost imaging has a positive effect on suppressing atmospheric turbulence, but its reconstruction results are not stable, and it cannot get high-quality images under extreme conditions. In this paper, we simulate atmospheric turbulence using a phase screen, combine computational ghost imaging to simulate the imaging process, and analyze the factors that affect the imaging. We use an end-to-end neural network to input the bucket signal into the network after processing, which can not only reconstruct the target image directly but also save reconstruction time by removing the process of correlation calculation. Simulations show that good reconstruction results can be obtained at low sampling rates and extreme conditions.

4.
Appl Opt ; 61(29): 8850-8858, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256021

RESUMO

Multimode optical fiber plays an important role in endoscope miniaturization. With the development of deep learning and machine learning, neural networks can be used to identify and classify speckle patterns obtained at the fiber output. Based on the speckle pattern of a HERLEV dataset cell image transmitted by a multimode fiber, this paper studies the recognition accuracy of various types of speckle by a support vector machine, K-nearest neighbor, and convolutional neural network (Inception V3). Meanwhile, we propose an image classification optimization algorithm based on improved Inception V3. The experimental results show that the improved algorithm model is better than the traditional machine learning method; the accuracy rate is 97.92%, which effectively improves the performance of the pathological cell diagnosis deep learning model and lays a theoretical and practical foundation for further clinical application.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Máquina de Vetores de Suporte , Algoritmos , Fibras Ópticas
5.
IEEE Trans Pattern Anal Mach Intell ; 44(2): 890-904, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32750837

RESUMO

We propose an efficient algorithm for solving orthogonal canonical correlation analysis (OCCA) in the form of trace-fractional structure and orthogonal linear projections. Even though orthogonality has been widely used and proved to be a useful criterion for visualization, pattern recognition and feature extraction, existing methods for solving OCCA problem are either numerically unstable by relying on a deflation scheme, or less efficient by directly using generic optimization methods. In this paper, we propose an alternating numerical scheme whose core is the sub-maximization problem in the trace-fractional form with an orthogonality constraint. A customized self-consistent-field (SCF) iteration for this sub-maximization problem is devised. It is proved that the SCF iteration is globally convergent to a KKT point and that the alternating numerical scheme always converges. We further formulate a new trace-fractional maximization problem for orthogonal multiset CCA and propose an efficient algorithm with an either Jacobi-style or Gauss-Seidel-style updating scheme based on the SCF iteration. Extensive experiments are conducted to evaluate the proposed algorithms against existing methods, including real-world applications of multi-label classification and multi-view feature extraction. Experimental results show that our methods not only perform competitively to or better than the existing methods but also are more efficient.

6.
Bioinformatics ; 35(20): 4029-4037, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30918942

RESUMO

MOTIVATION: Multiview clustering has attracted much attention in recent years. Several models and algorithms have been proposed for finding the clusters. However, these methods are developed either to find the consistent/common clusters across different views, or to identify the differential clusters among different views. In reality, both consistent and differential clusters may exist in multiview datasets. Thus, development of simultaneous clustering methods such that both the consistent and the differential clusters can be identified is of great importance. RESULTS: In this paper, we proposed one method for simultaneous clustering of multiview data based on manifold optimization. The binary optimization model for finding the clusters is relaxed to a real value optimization problem on the Stiefel manifold, which is solved by the line-search algorithm on manifold. We applied the proposed method to both simulation data and four real datasets from TCGA. Both studies show that when the underlying clusters are consistent, our method performs competitive to the state-of-the-art algorithms. When there are differential clusters, our method performs much better. In the real data study, we performed experiments on cancer stratification and differential cluster (module) identification across multiple cancer subtypes. For the patients of different subtypes, both consistent clusters and differential clusters are identified at the same time. The proposed method identifies more clusters that are enriched by gene ontology and KEGG pathways. The differential clusters could be used to explain the different mechanisms for the cancer development in the patients of different subtypes. AVAILABILITY AND IMPLEMENTATION: Codes can be downloaded from: http://homepage.fudan.edu.cn/sqzhang/files/2018/12/MVCMOcode.zip. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Algoritmos , Neoplasias , Análise por Conglomerados , Ontologia Genética , Humanos
8.
Zhong Yao Cai ; 38(8): 1694-8, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26983247

RESUMO

OBJECTIVE: To study the protective effects of ginkgolide N against glutamte-induced injury in PC12 cells and its mechanisms. METHODS: The injury model was established by treating PC12 cells with glutamate, and PC12 cells were treated with different concentrations of ginkgolide N with ginkgolide B as control. The cells activity was analyzed by MTT assay. The apoptosis of PC12 cells were examined by acridine orange( AO) staining, the reactive oxygen species and mitochondrial membrane potential of PC12 cells were examined by flow cytometry. Western blot method was used to examine the expression of Cleaved Caspase-3 protein. RESULTS: Ginkgolides N of 2-8 µgmol/L inhibited PC12 cells apoptosis and ROS accumulation induced by glutamate,stabilized membrane potential of damaged PC12, and reduced the expression of Cleaved Caspase-3 protein. CONCLUSION: Ginkgolide N has a protective effect on PC12 cells injury induced by glutamate, and the mechanism may be associated with reducing ROS generation, stabilizing membrane potential and inhibiting the expression of Cleaved Caspase-3 protein.


Assuntos
Ginkgolídeos/farmacologia , Ácido Glutâmico/efeitos adversos , Potencial da Membrana Mitocondrial , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose , Caspase 3/metabolismo , Células PC12/efeitos dos fármacos , Ratos
9.
Zhong Yao Cai ; 36(12): 2067-71, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-25090693

RESUMO

OBJECTIVE: To provide reference for the government to formulate policies and medical institution to formulate development plan, the present situation of medical institutions of traditional Chinese preparation and some countermeasures for developing the research of traditional Chinese preparation in Guangdong province were studied. METHODS: Combined with development situation of traditional Chinese preparation of medical institutions in Guangdong province in recent years, the development countermeasure of traditional Chinese preparation was discussed. RESULTS: In order to promote the development of traditional Chinese preparation of medical institutions, suggestions and countermeasures for the government and related departments were proposed. CONCLUSION: Government departments should formulate policies to support the development of traditional Chinese preparation, the medical institutions should make scientific development planning, strengthen the construction of hardware and software and develop special traditional Chinese preparation to promote the healthy development of traditional Chinese preparation.


Assuntos
Medicina Tradicional Chinesa/normas , Preparações Farmacêuticas/normas , China , Coleta de Dados/métodos , Composição de Medicamentos/normas , Medicamentos de Ervas Chinesas , Administração Hospitalar , Humanos , Desenvolvimento de Programas , Controle de Qualidade , Inquéritos e Questionários
10.
J Nat Med ; 67(2): 375-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22689153

RESUMO

Four new cycloartane glycosides, 3-O-ß-D-xylopyranosyl-(1 → 6)-ß-D-glucopyranosyl-(1 → 4)-ß-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3ß,22,26-triol 26-O-(6-O-acetyl)-ß-D-glucopyranoside (1), 3-O-α-L-arabinopyranosyl-(1 → 6)-ß-D-glucopyranosyl-(1 → 4)-ß-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3ß,22,26-triol 26-O-(6-O-acetyl)-ß-D-glucopyranoside (2), 3-O-ß-D-glucopyranosyl (24S)-cycloartane-3ß,16ß,24,25,30-pentaol 25-O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranoside (3) and 3-O-ß-D-glucopyranosyl (24S)-cycloartane-3ß,16ß,24,25,30-pentaol 25-O-ß-D-glucopyranosyl-(1 → 4)-ß-D-glucopyranoside (4), were isolated from the aerial parts of Thalictrum fortunei. Their structures were established on the basis of extensive NMR and HR-ESI-MS analyses, along with acid hydrolysis.


Assuntos
Glicosídeos/química , Componentes Aéreos da Planta/química , Thalictrum/química , Triterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
11.
Zhong Yao Cai ; 34(5): 687-90, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21954552

RESUMO

OBJECTIVE: To develop a HPLC- ELSD method for determination the contents of geniposide, crocin and crocetin in different processing products of Fructus Gardeniae. METHODS: The separation was performed in the HyperClone ODS C18 column (250 mm x 4. 6 mm, 5 microm) with linear gradient elution using methanol-water and 0.05% phosphoric acid in water, the flowing rate was 0.8 mL/min, the column temperature was 30 degrees C, and the ELSD parameter was as follow: 70 degrees C as atomization temperature and 2.0 L/min as the gas flowing rate. RESULTS: The contents of geniposide and crocin in raw, yellowish, carbocoal and scorched Fructus Gardeniae decreased with the deepening of processing degree. However, the content of crocetin in carbocoal and scorched Fructus Gardeniae increased comparing with the raw one. CONCLUSION: This is a simple and credible quality control method, and can be used for the quality control and comprehensive evaluation for different processed products of Fructus Gardeniae.


Assuntos
Carotenoides/análise , Cromatografia Líquida de Alta Pressão/métodos , Gardenia/química , Iridoides/análise , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Frutas/química , Controle de Qualidade , Reprodutibilidade dos Testes , Tecnologia Farmacêutica/métodos , Vitamina A/análogos & derivados
12.
J Asian Nat Prod Res ; 13(9): 845-50, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21830890

RESUMO

Two new monoterpenoid glycosides, α-(E)-acaridiol 8-O-ß-d-glucopyranoside (1) and α-(E)-acaridiol 9-O-ß-d-glucopyranoside (2), as well as a new thiophen, 2-acetyl-3-hydroxy-5-(prop-1-ynyl)thiophen 3-O-ß-d-glucopyranoside (3), were isolated from the roots of Eupatorium chinense. Their structures were determined on the basis of extensive spectroscopic and chemical analyses.


Assuntos
Eupatorium/química , Glucosídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Monoterpenos/isolamento & purificação , Tiofenos/isolamento & purificação , Glucosídeos/química , Glicosídeos/química , Estrutura Molecular , Monoterpenos/química , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Tiofenos/química
13.
Zhong Yao Cai ; 31(2): 224-6, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18619266

RESUMO

OBJECTIVE: To study the chemical constituents of the herb of Lygodium japonicum. METHODS: The constituents isolated by column chromatography and their structrues were elucidated through spectroscopic analysis. RESULTS: The compounds were identified as 3,4-dihydroxyl benzoic acid 4-O-beta-D-(4'-O-methyl) glucopyranoside (I), protocatechuic acid (II), acacetin 7-O-(6'-O-a-L-rhamnopyranosyl)-beta-sophoroside (III), 6,8-di-glucosylapigenin (vinenin) (IV), tricin-7-O-beta-D-glucopyranoside (V), 2-anilino-1,4-naphthoquinone (VI). CONCLUSION: All these compounds are obtained from Lygodiaeae for the first time.


Assuntos
Gleiquênias/química , Flavonoides/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Plantas Medicinais/química , Flavonoides/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Hidroxibenzoatos/química , Componentes Aéreos da Planta/química
14.
Zhongguo Zhong Yao Za Zhi ; 32(13): 1300-2, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17879730

RESUMO

OBJECTIVE: To investigate the chemical constituents of the root barks of Periploca sepium. METHOD: Column chromatographic techniques were used to isolate the chemical constituents. NMR and MS methods were employed for their structural elucidation. RESULT: Eight compounds were isolated and identified as isovanillin (1), vanillin (2), 4-methoxysalicylic acid (3), (24R)-9, 19-cycloart-25-ene-3beta, 24-diol (4), (24S)-9, 19-cycloart-25-ene-3beta, 24-diol (5), cycloeucalenol (6), beta-amyrin acetate (7) and alpha-amyrin (8). CONCLUSION: Compounds 1-6 were isolated from this plant for the first time.


Assuntos
Periploca/química , Fitosteróis/isolamento & purificação , Casca de Planta/química , Raízes de Plantas/química , Triterpenos/isolamento & purificação , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Estrutura Molecular , Fitosteróis/química , Plantas Medicinais/química , Triterpenos/química
15.
Fitoterapia ; 78(7-8): 600-1, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17570612

RESUMO

A new phenolic glycoside, 3,4-dihydroxybenzoic acid 4-O-(4'-O-methyl)-beta-D-glucopyranoside (1), was isolated from the roots of Lygodium japonicum. The structure was elucidated on the basis of spectroscopic methods.


Assuntos
Gleiquênias/química , Fitoterapia , Extratos Vegetais/química , Glicosídeos/química , Humanos , Fenóis/química , Raízes de Plantas
16.
Chem Pharm Bull (Tokyo) ; 54(1): 107-10, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16394560

RESUMO

Four new cycloartane glycosides were isolated from the aerial parts of Thalictrum fortunei (Ranunculaceae). The chemical structures of these new glycosides were elucidated as 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3beta,22,26-triol 26-O-beta-D-glucopyranoside, 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3beta,22,26-triol 26-O-beta-D-quinovopyranosyl-(1-->6)-beta-D-glucopyranoside, 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3beta,22,26-triol 26-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside, and 3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-fucopyranosyl (22S,24Z)-cycloart-24-en-3beta,22,26-triol 26-O-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside by extensive NMR methods, HR-ESI-MS, and hydrolysis. This is the first report of (22S,24Z)-3beta,22,26-trihydroxycycloartan-24-ene (thelictogenin A, 5) being glycosylated at C-26.


Assuntos
Thalictrum/química , Triterpenos/química , Configuração de Carboidratos , Sequência de Carboidratos , Glicosídeos/química , Glicosídeos/isolamento & purificação , Hidrólise , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/isolamento & purificação
17.
Zhongguo Zhong Yao Za Zhi ; 30(19): 1522-4, 2005 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-16335824

RESUMO

OBJECTIVE: To study the chemical constituents of Lygodium japonicum. METHOD: Column chromatographic techniques were used for isolation and purification of chemical constituents of this plant and their structures were identified by spectroscopic analysis. RESULT: Eight compounds were isolated and identified as tilianin (I), kaempferol-7-O-alpha-L-rhamnopyranoside (II), kaempferol (III), p-coumaric acid (IV), hexadecanoic acid 2, 3-dihydroxy-propyl ester (V), daucosterol (VI), beta-sitosterol (VII, and 1-hentriacontanol (VIII) respectively. CONCLUSION: Compounds I, II, V, VI, VII, VIII were isolated from L. japonicum for the first time, compounds I, II, V were isolated from genus Lygodium for the first time.


Assuntos
Gleiquênias/química , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Quempferóis/isolamento & purificação , Plantas Medicinais/química , Flavonoides/química , Glicosídeos/química , Quempferóis/química , Componentes Aéreos da Planta/química
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