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1.
Opt Express ; 25(22): 26825-26831, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29092167

RESUMO

The functionality of a pulse timing discriminator, which is commonly required in optical communication systems and artificial neuromorphic engineering, was implemented into chalcogenide phase-change materials. GeSbTe (GST) and GeCuTe (GCT), which exhibit opposite refractive index behavior in their respective crystalline and amorphous phases, were employed. A GST/GCT double layer enabled the order of arrival of two counter-propagating femtosecond pulses to be encoded as a difference in the degree of amorphization of the GCT layer, i.e., either a brighter or darker contrast of the amorphized area with respect to the crystalline background. Nonthermal ultrafast amorphization contributed to a picosecond time resolution in the discrimination of the pulse arrival order.

2.
Cell Signal ; 25(1): 41-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23000341

RESUMO

FLJ00018/PLEKHG2 is a guanine nucleotide exchange factor for the Rho family small GTPases. FLJ00018 is directly activated by heterotrimeric G protein Gßγ subunits. Using two-hybrid screening, we have identified non-muscle cytosolic actin as a binding partner of FLJ00018. We found that there were two actin-binding regions in FLJ00018 at the N-terminal region (150-283 amino acids) and at the C-terminal region (465-1386 amino acids). The overexpression of non-muscle cytosolic actin attenuated the FLJ00018-induced serum response element-dependent gene transcription. These results suggest that non-muscle cytosolic actin may be a negative regulator of FLJ00018 through its interaction with the Dbl homology domain.


Assuntos
Actinas/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Actinas/genética , Animais , Subunidades beta da Proteína de Ligação ao GTP/genética , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/genética , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/genética , Células HEK293 , Humanos , Camundongos , Células NIH 3T3 , Ligação Proteica , Estrutura Terciária de Proteína , Elemento de Resposta Sérica , Transcrição Gênica , Transfecção , Técnicas do Sistema de Duplo-Híbrido
3.
Bioresour Technol ; 135: 652-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23265817

RESUMO

This study has demonstrated that microcapsules can be used as a microreactor for the transesterification of rapeseed oil with calcium oxide (CaO) base catalyst. CaO-loaded microcapsules were prepared by coextrusion technique, and the transesterification reaction was carried out by adding methanol into the prepared microcapsules and oil in a batch-type reactor. Results showed that the microcapsules system could promote the transesterification and hinder the dissolution of the catalyst, in contrast to a biodiesel production with CaO particles. The optimal conditions for methanol to oil molar ratio, catalyst content in the microcapsules and reaction temperature were found to be 8:1, 20 wt.%, and 65 °C, respectively. The results of reusability tests showed that CaO-loaded microcapsules could be successfully reused for three times without loss of the catalytic activity. It was concluded from these results that microcapsules have the potential to improve the performance of solid base catalyst for biodiesel production.


Assuntos
Cápsulas/química , Metano/metabolismo , Óleos de Plantas/metabolismo , Compostos de Cálcio/farmacologia , Catálise/efeitos dos fármacos , Esterificação/efeitos dos fármacos , Ésteres/metabolismo , Ácidos Graxos Monoinsaturados , Metanol/metabolismo , Óxidos/farmacologia , Óleo de Brassica napus , Reciclagem , Temperatura
4.
Chirality ; 20(3-4): 577-84, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18172835

RESUMO

In order to clarify factor(s) determining the pattern of a hydrogen-bonding network in the diastereomeric salts of 1-arylethylamines (1) with enantiopure P-chiral acids, three kinds of enantiopure P-chiral alkylphenylphosphinothioic acids (3) were synthesized, and their chiral recognition abilities for racemic 1 were examined. The characteristics of the diastereomeric salt crystals of 1 with 3 were then studied on the basis of their X-ray crystallographic analyses. Statistical analysis on the molecular conformations observed in the diastereomeric salts with 3 as well as those with P-chiral O-alkyl arylphosphonothioic acids (2), which have a chemical structure similar to that of 3, and molecular orbital calculations for 2 and 3 in a gas phase revealed that the torsion angle between the aromatic plane and the P--O(alkoxy in 2) or P--C(alkyl in 3) plays an important role in determining the pattern of a hydrogen-bonding network in the diastereomeric salts, either a closed globular cluster or an infinite 2(1) column type. The calculations also indicated that there is a hydrogen-bonding-like interaction between the ammonium hydrogen atom of 1-arylethylammonium cations and the P--O(alkoxy) oxygen atom of phosphonothioate anions in the clusters.

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