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1.
Ultrasonics ; 117: 106548, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34438222

RESUMO

Acoustic tweezing and contactless object manipulation are significant and has become a research hotspot. Here, we present a prototype of retroreflection tweezer based on the metagratings, which can be used for implementing particle levitation and contactless movement. Different from previous tweezers, where the standing wave was typically generated from normal incidence, the retroreflection tweezer proposed here operates for the oblique incidence case that provides more degrees of freedom for real-time observation. We also give the exact relation between the metagrating geometries and retroreflection angles in a wide range based on the grating theory and optimization algorithm. Experiments are conducted to show the retroreflection at a preset angle on the designed metagrating, where levitation and contactless movement of particles are demonstrated.

2.
Zhongguo Zhong Yao Za Zhi ; 43(21): 4226-4230, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30583622

RESUMO

To construct CRISPR/Cas9 vectors for the editing of SmPAL1 in the phenylpropane metabolic pathway of Salvia miltiorrhiza, CIRSPR/Cas9 target sites of SmPAL1 were designed by online software. Its target efficiencies were detected in vitro by enzyme digestion and sequences with highly efficiency were constructed into CRISPR/Cas9 vectors. Three possible CRISPR target sequences (SmPAL1-g1, SmPAL1-g2, SmPAL1-g3) were designed and the enzyme digestion efficiencies were 53.3%, 76.6% and 10.0%. SmPAL1-g1 and SmPAL1-g2 were constructed into vector VK005-03 named as VK005-03-g1 and VK005-03-g2. The results of sequencing showed that the two CRISPR/Cas target sequences were all constructed into VK005-03. Here we first laid the foundation for the study of SmPAL1 and provided an effective strategy for the screening of sgRNA.


Assuntos
Sistemas CRISPR-Cas , Redes e Vias Metabólicas/genética , Salvia miltiorrhiza/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Salvia miltiorrhiza/química
3.
Zhong Yao Cai ; 37(5): 740-3, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25335277

RESUMO

OBJECTIVE: To study the physiological trait changes in the growth process of different varieties of Lonicera japonica, and to explore the growth regularity. METHODS: Length, color, flowering rate and drying rate in the growth and development process of different varieties of Lonicera japonica were observed. Nonlinear regression analysis was used to conclude the growth simulation curve equation. RESULTS: Among different varieties and different sections of the same branch, the growth showed a similar law, the drying rates of the 'sanqing' period got the maximum value in all of the three varieties, the weight of the flower in 'erbai' period was the highest, and no differences between varieties. The R2 of the two curve equations was 0.996 and 0.995, respectively. CONCLUSION: Both of two curve equations can reply the growth regularity of Lonicera japonica flower very well. Study on the growth process systematically can guide the agricultural production very well.


Assuntos
Flores/crescimento & desenvolvimento , Lonicera/crescimento & desenvolvimento , Modelos Estatísticos , Biomassa , Flores/genética , Lonicera/classificação , Lonicera/genética , Estações do Ano , Especificidade da Espécie
4.
World J Gastroenterol ; 14(39): 6004-11, 2008 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-18932278

RESUMO

AIM: To observe the effect of berberine on insulin secretion in rat pancreatic islets and to explore its possible molecular mechanism. METHODS: Primary rat islets were isolated from male Sprague-Dawley rats by collagenase digestion and treated with different concentrations (1, 3, 10 and 30 micromol/L) of berberine or 1 micromol/L Glibenclamide (GB) for 24 h. Glucose-stimulated insulin secretion (GSIS) assay was conducted and insulin was determined by radioimmunoassay. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate cytotoxicity. The mRNA level of hepatic nuclear factor 4 alpha (HNF4alpha) was determined by reverse transcription polymerase chain reaction (RT-PCR). Indirect immunofluorescence staining and Western blot analysis were employed to detect protein expression of HNF4alpha in the islets. Glucokinase (GK) activity was measured by spectrophotometric method. RESULTS: Berberine enhanced GSIS rather than basal insulin secretion dose-dependently in rat islets and showed no significant cytotoxicity on islet cells at the concentration of 10 mumol/L. Both mRNA and protein expressions of HNF4alpha were up-regulated by berberine in a dose-dependent manner, and GK activity was also increased accordingly. However, GB demonstrated no regulatory effects on HNF4alpha expression or GK activity. CONCLUSION: Berberine can enhance GSIS in rat islets, and probably exerts the insulinotropic effect via a pathway involving HNF4alpha and GK, which is distinct from sulphonylureas (SUs).


Assuntos
Berberina/farmacologia , Glucoquinase/metabolismo , Fator 4 Nuclear de Hepatócito/metabolismo , Ilhotas Pancreáticas/metabolismo , Extratos Vegetais/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Glucose/farmacologia , Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
5.
Zhongguo Zhong Yao Za Zhi ; 33(22): 2595-8, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19216149

RESUMO

OBJECTIVE: To study the relationship between photosynthetic characteristics and environmental factors in leaves of P. lobata. METHOD: Photosynthetic characteristics and environmental factors were measured by using CIRAS-2 portable photosynthesis system. RESULT: The apparent quantum yield in leaves was 0.0173 micromol CO2 x micromol(-1) photon. The dark respiration rate was 2.9333 micromol x m(-2) x s(-1). The light compensation point of photosynthesis was 180 micromol x m(-2) x s(-1). The light saturation point was 1600 micromol x m(-2) x s(-1). The carboxylation efficiency was 0.0338 micromol x m(-2) x s(-1). The light respiration rate was 2.5 micromol x m(-2) x s(-1). The CO2 compensation point was 100 micromol x mol(-1), The CO2 saturation point was 1 600 micromol x mol(-1). CONCLUSION: Photo flux density and air temperature are major environmental factors influencing diumal changes of net photosynthetic rate.


Assuntos
Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Pueraria/metabolismo
6.
Zhongguo Zhong Yao Za Zhi ; 30(17): 1331-4, 2005 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-16323540

RESUMO

OBJECTIVE: To purify salvianolic acids by macroreticular resin,then mensurate the contents of salvianolic acids and analyse the chromatogram with HPLC. METHOD: Make salvianolic acids with macroreticular resin; mensurate the content of Salvianolic acids with UV spestrophotometry: the control compound is protocaechuic aldehyde, and the wavelength is 281 nm. Analysis the chromatogram with HPLC, and compare the chromatogram in different technics: zorbax ODS column (4.6 mm x 250 mm, 5 microm), mobilephase: 1% aceticacid-water and methanol in different proportions, the wavelength is 281 nm. RESULT: The contents of salvianolic acids is 53.8%; HPLC chromatogram indicate that the method is reasonable to make salvianolic acids. CONCLUSION: Determination of contents and HPLC chromatogram can control the quality of Salvianolic acids more accurately.


Assuntos
Benzofuranos/isolamento & purificação , Ácidos Cafeicos/isolamento & purificação , Resinas de Troca Iônica , Lactatos/isolamento & purificação , Salvia miltiorrhiza/química , Benzofuranos/análise , Ácidos Cafeicos/análise , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Lactatos/análise
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