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2.
Nanomaterials (Basel) ; 10(8)2020 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-32751542

RESUMEN

Silicon suboxide (SiOx, x ≈ 1) is a substoichiometric silicon oxide with a large refractive index and optical absorption coefficient that oxidizes to silica (SiO2) by annealing in air at ~1000 °C. We demonstrate that nanostructures with a groove period of 200-330 nm can be formed in air on a silicon suboxide film with 800 nm, 100 fs, and 10 Hz laser pulses at a fluence an order of magnitude lower than that needed for glass materials such as fused silica and borosilicate glass. Experimental results show that high-density electrons can be produced with low-fluence femtosecond laser pulses, and plasmonic near-fields are subsequently excited to create nanostructures on the surface because silicon suboxide has a larger optical absorption coefficient than glass. Calculations using a model target reproduce the observed groove periods well and explain the mechanism of the nanostructure formation.

3.
Plant Cell Physiol ; 61(10): 1750-1759, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32706881

RESUMEN

SNAREs (soluble N-ethyl maleimide-sensitive factor attachment protein receptors) mediate membrane fusion of vesicle transport in eukaryotic cells. LjSYP132s are the members of Qa-SNAREs in Lotus japonicus. Two isoforms, LjSYP132a and LjSYP132b, are generated by alternative splicing. Immunoblot analysis detected strong expression of LjSYP132s in infected root nodules and seeds by posttranscriptional modification. In either LjSYP132a or LjSYP132b silenced roots (RNAi-LjSYP132a, RNAi-LjSYP132b), the infection thread (IT) was not elongated, suggesting that both LjSYP132a and LjSYP132b have a role in IT progression. The results were consistent with the data of qRT-PCR showing that both genes were expressed at the early stage of infection. However, during the nodulation, only LjSYP132a was induced. LjSYP132s protein was observed in the Mesorhizobium loti-inoculated roots of mutants, nfr1, castor and pollux, suggesting that LjSYP132s can be induced without Nod factor signaling. Accumulation of LjSYP132s in the peribacteroid membrane suggests the function of not only IT formation but also nutrient transport. In contrast, qRT-PCR showed that LjSYP132b was expressed in the seeds. A stable transgenic plant of LjSYP132b, R132b, was produced by RNAi silencing. In the R132b plants, small pods with a few seeds and abnormal tip growth of the pollen tubes were observed, suggesting that LjSYP132b has a role in pollen tube growth and nutrient transport in the plasma membrane of seeds.


Asunto(s)
Lotus/crecimiento & desarrollo , Proteínas de Plantas/fisiología , Nodulación de la Raíz de la Planta , Proteínas SNARE/fisiología , Semillas/crecimiento & desarrollo , Empalme Alternativo , Regulación de la Expresión Génica de las Plantas , Lotus/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/fisiología , Interferencia de ARN , Proteínas SNARE/metabolismo , Semillas/metabolismo
4.
Bull Tokyo Dent Coll ; 61(2): 103-120, 2020 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-32522935

RESUMEN

Narrowing of the maxillary dental arch is a major cause of occlusal abnormalities in cleft lip and palate patients. Although the dental arch may be expanded in such cases, relapse will often occur during the subsequent retention period. In this study, the stability of expansion of the maxillary arch was investigated by examining 3-dimensional change in the maxillary arch during the treatment and post-retention periods. Three-dimensional measurements was performed on maxillary plaster models obtained from 8 unilateral cleft lip and palate patients (mean age, 12.5 years) who had undergone maxillary arch expansion using an edgewise appliance and quad helix (CLP group). The controls consisted of 8 unilateral cleft lip and alveolus patients (mean age, 12.9 years). Measurements were made during the pretreatment, post-treatment, and post-retention periods. In the CLP group, horizontal relapse was observed in the alveolar and dental arches between the second premolars, together with vertical relapse on the cleft side of the central incisor, lateral incisor, and canine. The sites where relapse occurred demonstrated decreased growth before orthodontic treatment. A correlation was observed between the extents of expansion and relapse. These findings suggest that excessive horizontal or vertical tooth movement in areas showing developmental failure should be avoided in order to increase stability after orthodontic treatment.


Asunto(s)
Labio Leporino , Fisura del Paladar , Niño , Arco Dental , Humanos , Maxilar , Técnica de Expansión Palatina
5.
J Org Chem ; 85(13): 8371-8386, 2020 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-32524816

RESUMEN

Diversity-oriented synthesis (DOS) is an effective strategy for the quick creation of diverse and high three-dimensional compounds from simple starting materials. The selection of a starting material is the key to constructing useful, chemically diverse compound libraries for the development of new drugs. Here, we report a novel, general, and facile strategy for the creation of diverse compounds with high structural diversity from readily available natural products, such as zerumbone, as the synthetic starting material. Zerumbone is the major component of the essential oil from wild ginger, Zingiber zerumbet Smith. It is noteworthy that zerumbone has a powerful latent reactivity, partly because of its three double bonds, two conjugated and one isolated, and a double conjugated carbonyl group in an 11-membered ring structure. In fact, zerumbone has been shown to be a successful example of natural material-related DOS (NMRDOS). We will report that zerumbone can be converted in one chemical step from four zerumbone derivatives into rare and markedly different scaffolds by transannulation.

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