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1.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4116-4120, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872686

RESUMO

With digital satellite remote sensing image data of GF-1,in 2018 the object-oriented classification method was used to extract Zizyphus jujuba planting area in Jia county of Shaanxi province. The results showed that the remote sensing classification method based on rule set could extract and reckon Z. jujube planting area in the study area effectively. The planting area of Z. jujube in Jia county was about 5. 34×104 hm2 and the area of consistent accuracy was 97. 92%. The method used in this study could provide a technical reference for the area extraction of the same type of medicinal materials. And it is of great significance to provide decision support for the protection and utilization of Z. jujube resources.


Assuntos
Ziziphus , Agricultura , China , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa
2.
Opt Express ; 27(5): 6660-6671, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876246

RESUMO

Cavity-enhanced optical controlling is experimentally observed with a low-control laser power in a cavity-atom ensemble system. Here, the three-level atoms are coupled with two optical modes of a Fabry-Perot cavity, where a new theoretical model is developed to describe the effective three-wave mixing process between spin-wave and optical modes. By adjusting either temperature or cavity length, we demonstrate the precise frequency tuning of the hybrid optical-atomic resonances. When the doubly-resonant condition is satisfied, the probe laser can be easily modulated by a control laser. In addition, interesting non-Hermitian physics are predicted theoretically and demonstrated experimentally, and all-optical switching is also achieved. Such a doubly-resonant cavity-atom ensemble system without a specially designed cavity can be used for future applications, such as optical signal storage and microwave-to-optical frequency conversion.

3.
Nat Commun ; 9(1): 1797, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29728619

RESUMO

Non-reciprocal devices, which allow non-reciprocal signal routing, serve as fundamental elements in photonic and microwave circuits and are crucial in both classical and quantum information processing. The radiation-pressure-induced coupling between light and mechanical motion in travelling-wave resonators has been exploited to break the Lorentz reciprocity, enabling non-reciprocal devices without magnetic materials. Here, we experimentally demonstrate a reconfigurable non-reciprocal device with alternative functions as either a circulator or a directional amplifier via optomechanically induced coherent photon-phonon conversion or gain. The demonstrated device exhibits considerable flexibility and offers exciting opportunities for combining reconfigurability, non-reciprocity and active properties in single photonic devices, which can also be generalized to microwave and acoustic circuits.

4.
Opt Express ; 24(11): 12336-48, 2016 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-27410149

RESUMO

Synchronization is of great scientific interest due to the abundant applications in a wide range of systems. We propose an all-optical scheme to achieve the controllable long-distance synchronization of two dissimilar optomechanical systems, which are unidirectionally coupled through a fiber with light. Synchronization, unsynchronization, and the dependence of the synchronization on driving laser strength and intrinsic frequency mismatch are studied based on the numerical simulation. Taking the fiber attenuation into account, we show that two optomechanical resonators can be unidirectionally synchronized over a distance of tens of kilometers. We also analyze the unidirectional synchronization of three optomechanical systems, demonstrating the scalability of our scheme.

5.
Plant Cell Physiol ; 57(6): 1244-56, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27296714

RESUMO

Grassbur is a destructive and invasive weed in pastures, and its burs can cause gastric damage to animals. The strong adaptability and reproductive potential of grassbur are partly due to a unique germination mechanism whereby twin seeds develop in a single bur: one seed germinates, but the other remains dormant. To investigate the molecular mechanism of seed germination in twin seeds, we used isobaric tags for relative and absolute quantitation (iTRAQ) to perform a dynamic proteomic analysis of germination and dormancy. A total of 1,984 proteins were identified, 161 of which were considered to be differentially accumulated. The differentially accumulated proteins comprised 102 up-regulated and 59 down-regulated proteins. These proteins were grouped into seven functional categories, ribosomal proteins being the predominant group. The authenticity and accuracy of the results were confirmed by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time reverse transcription-PCR (qPCR). A dynamic proteomic analysis revealed that ribosome synthesis and carbohydrate metabolism affect seed germination possibly through the phosphoinositide 3-kinase (PI3K) pathway. As the PI3K pathway is generally activated by insulin, analyses of seeds treated with exogenous insulin by qPCR, ELISA and iTRAQ confirmed that the PI3K pathway can be activated, which suppresses dormancy and promotes germination in twin grassbur seeds. Together, these results show that the PI3K pathway may play roles in stimulating seed germination in grassbur by modulating ribosomal synthesis and carbohydrate metabolism.


Assuntos
Metabolismo dos Carboidratos , Marcação por Isótopo/métodos , Fosfatidilinositol 3-Quinases/metabolismo , Dormência de Plantas , Plantas Daninhas/fisiologia , Proteômica/métodos , Ribossomos/metabolismo , Sementes/metabolismo , Metabolismo dos Carboidratos/efeitos dos fármacos , Ciclo do Ácido Cítrico/efeitos dos fármacos , DNA de Plantas/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Insulina/farmacologia , Dormência de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/enzimologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA de Plantas/metabolismo , Ribossomos/efeitos dos fármacos , Sementes/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
6.
Opt Express ; 23(19): 25118-27, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26406711

RESUMO

We propose a new approach to realize all-optical circulator based on stimulated Brillouin scattering in an integrated microresonator. Stimulated Brillouin scattering is a basic interaction between photon and traveling acoustic wave resulted from electrostriction and photoelastic effects. Due to the phase-matching requirement, the circulating acoustic wave can only couple to probe light which propagating along or opposite to the pump laser direction, thus exhibits a non-reciprocal phase shift. Combined with Mach-Zehnder interferometer, the optical circulator can be realized. Though the bandwidth is relatively small because of the narrow-band nature of microresonator, this magnetic-free all-optical integrated circulator may be applied for future on-chip photonic information processing.

7.
Nat Commun ; 6: 6193, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25648234

RESUMO

Stimulated Brillouin scattering is a fundamental interaction between light and travelling acoustic waves and arises primarily from electrostriction and photoelastic effects, with an interaction strength several orders of magnitude greater than that of other relevant non-linear optical processes. Here we report an experimental demonstration of Brillouin-scattering-induced transparency in a high-quality whispering-gallery-mode optical microresonantor. The triply resonant Stimulated Brillouin scattering process underlying the Brillouin-scattering-induced transparency greatly enhances the light-acoustic interaction, enabling the storage of light as a coherent, circulating acoustic wave with a lifetime up to 10 µs. Furthermore, because of the phase-matching requirement, a circulating acoustic wave can only couple to light with a given propagation direction, leading to non-reciprocal light storage and retrieval. These unique features establish a new avenue towards integrated all-optical switching with low-power consumption, optical isolators and circulators.

8.
Org Lett ; 16(10): 2732-5, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24805285

RESUMO

A general and efficient palladium-catalyzed intermolecular direct C-H homocoupling of furans and thiophenes has been developed. The reaction is characterized by using molecular oxygen as the sole oxidant and complete C5-position regioselectivity. Both C2- and C3-substituted furans or thiophenes are appropriate substrates. The approach provides a straightforward, facile, and economical route to bifurans and bithiophenes under mild reaction conditions.


Assuntos
Furanos/química , Compostos Heterocíclicos com 2 Anéis/síntese química , Oxidantes/química , Oxigênio/química , Paládio/química , Tiofenos/química , Catálise , Técnicas de Química Combinatória , Furanos/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Estrutura Molecular , Tiofenos/síntese química
9.
Org Lett ; 16(6): 1610-3, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24606159

RESUMO

An efficient and economical palladium-catalyzed oxidation system has been identified. The oxidation system, characterized by not adding ligand and using molecular oxygen as the sole oxidant, can realize the Tsuji-Wacker oxidation of terminal olefins and especially styrenes to methyl ketones; in addition, this system can achieve tandem Wacker oxidation-dehydrogenation of terminal olefins to α,ß-unsaturated ketones.

10.
Org Lett ; 14(23): 5920-3, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23146075

RESUMO

A general and efficient palladium-catalyzed intermolecular direct C3 alkenylation of indoles using oxygen as the oxidant has been developed. The reaction is of complete regio- and stereoselectivity. All products are E-isomers at the C3-position, and no Z-isomers or 2-substituted product can be detected.


Assuntos
Alcenos/química , Indóis/química , Oxidantes/química , Paládio/química , Catálise , Estrutura Molecular , Oxigênio/química , Estereoisomerismo
12.
Zhonghua Nan Ke Xue ; 17(4): 291-5, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21548202

RESUMO

OBJECTIVE: To investigate the effects of Cox7a2 on the LH-induced testosterone production and the involved autophagy regulating signals in TM3 mouse Leydig cells. METHODS: The Cox7a2-pEYFP-N1 fluorescent protein vector was constructed and transfected into TM3 mouse Leydig cells. The level of testosterone was determined by ELISA, and the effects of Cox7a2 on the expression of the steroidogenic acute regulatory protein (StAR) and the phosphorylation of the autophagy regulatory factor P70S6K were detected by Western blot. RESULTS: LH stimulation increased the StAR protein expression and testosterone production, while Cox7a2 decreased P70S6K phosphorylation, reduced StAR expression and consequently inhibited LH-induced testosterone biosynthesis in the TM3 Leydig cells. CONCLUSION: Cox7a2 inhibits testosterone production by decreasing the StAR protein expression, which might be at least in part related with the activation of autophagy in TM3 mouse Leydig cells.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Células Intersticiais do Testículo/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Testosterona/biossíntese , Animais , Autofagia , Células Cultivadas , Hormônio Luteinizante/farmacologia , Masculino , Camundongos , Fosfoproteínas/metabolismo , Fosforilação
13.
Artigo em Chinês | MEDLINE | ID: mdl-24822351

RESUMO

The application of transgenes in Toxoplasma gondii research facilitates its genetic analysis. This article reviews the progress in construction of transgenes vector, transgenics in the research of T. gondii.


Assuntos
Toxoplasma/genética , Transgenes , Vetores Genéticos
14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 38(2): 218-21, 2006 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-16617371

RESUMO

A critical factor in the advancement of biomedical research is the ease with which data can be integrated, redistributed and analyzed both within and across domains. This paper summarizes the Biomedical Information Core Infrastructure built by National Cancer Institute Center for Bioinformatics in America (NCICB). The main product from the Core Infrastructure is caCORE--cancer Common Ontologic Reference Environment, which is the infrastructure backbone supporting data management and application development at NCICB. The paper explains the structure and function of caCORE: (1) Enterprise Vocabulary Services (EVS). They provide controlled vocabulary, dictionary and thesaurus services, and EVS produces the NCI Thesaurus and the NCI Metathesaurus; (2) The Cancer Data Standards Repository (caDSR). It provides a metadata registry for common data elements. (3) Cancer Bioinformatics Infrastructure Objects (caBIO). They provide Java, Simple Object Access Protocol and HTTP-XML application programming interfaces. The vision for caCORE is to provide a common data management framework that will support the consistency, clarity, and comparability of biomedical research data and information. In addition to providing facilities for data management and redistribution, caCORE helps solve problems of data integration. All NCICB-developed caCORE components are distributed under open-source licenses that support unrestricted usage by both non-profit and commercial entities, and caCORE has laid the foundation for a number of scientific and clinical applications. Based on it, the paper expounds caCORE-base applications simply in several NCI projects, of which one is CMAP (Cancer Molecular Analysis Project), and the other is caBIG (Cancer Biomedical Informatics Grid). In the end, the paper also gives good prospects of caCORE, and while caCORE was born out of the needs of the cancer research community, it is intended to serve as a general resource. Cancer research has historically contributed to many areas beyond tumor biology. At the same time, the paper makes some suggestions about the study at the present time on biomedical informatics in China.


Assuntos
Biologia Computacional , Sistemas de Gerenciamento de Base de Dados , Armazenamento e Recuperação da Informação , Informática Médica , National Cancer Institute (U.S.) , Software , Estados Unidos
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 37(4): 445-7, 2005 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-16086073

RESUMO

National Institutes of Health (NIH) released the biomedical research project NIH Roadmap Initiatives, including 3 themes, new pathways to discovery, research teams of the future, and re-engineering the clinical research enterprise. The purpose of the project is to catalyze to transform our new scientific knowledge into tangible benefits for people. Now, mostly of the project have begin to carry into practice.


Assuntos
Pesquisa Biomédica/tendências , Promoção da Saúde/métodos , Previsões , Humanos , National Institutes of Health (U.S.) , Objetivos Organizacionais , Apoio à Pesquisa como Assunto , Estados Unidos
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