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1.
RSC Adv ; 14(22): 15201-15208, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38737969

RESUMEN

Superhydrophobic treatment of wood can effectively reduce the interaction between wood and moisture, avoiding deformation, cracking, mould, and other defects caused by water absorption, which can extend the service life of wood and broaden the application field. Currently, the poor abrasion resistance of superhydrophobic wood is a crucial problem limiting its widespread application, and the preparation of superhydrophobic wood with robustness, abrasion resistance, and chemical resistance remains a huge challenge. In this work, robust bulk superhydrophobic wood with excellent abrasion resistance and chemical durability was fabricated by synthesizing porous poly(divinylbenzene) in wood cell cavities using graft copolymerization and solvothermal methods. The contact angles and rolling angles on the superhydrophobic wood surface were approximately 156° and 3°, respectively. Superhydrophobicity was carried through the entire structure of the wood. Even after severe damage by abrasion and sawing, as well as tests with organic solvents and harsh environments, the superhydrophobic properties of wood remained stable. Meanwhile, the superhydrophobic wood exhibited great self-cleaning and antifouling properties. In addition, the water uptake and dimensional stability of the wood were significantly improved. This work developed a simple, efficient, and durable strategy for the fabrication of superhydrophobic wood with robustness, abrasion resistance, and chemical resistance, which was expected to be applied to the wood industry to achieve the high-value applications of wood products and extend their service life.

2.
J Org Chem ; 89(5): 3111-3122, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38343173

RESUMEN

We herein present a study on the Ag(I)-mediated semipinacol rearrangement of iododifluorohomoallyl alcohols, the resulting allylic difluoromethyl ketones underwent oxidative allylic C-H esterification under palladium catalysis in the absence of external ligand. This process yielded a range of difluoromethyl ketones derived from allyl esters in a single operation. The reaction features broad scope of o-nitrobenzoic acids and homoallylic iododifluoroalcohols affording the targeted molecules in synthetically useful yields. Control experiments illustrated that the silver salt acted as not only a Lewis acid to promote the cleavage of a C-I bond and furnish the semipinacol rearrangement but also a co-oxidant in the catalytic cycle for the allylic C-H esterification.

3.
Org Lett ; 25(26): 4835-4839, 2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37358365

RESUMEN

In this report, we develop a new strategy for visible-light-induced, copper-catalyzed three-component difluoroalkyl thiocyanidation of alkenes to construct a series of important difluorothiocyanate compounds. The new approach can also be applied to perfluorothiocyanate compounds, even target molecules containing drug/natural product skeletons. Mechanistic studies provide that the copper complex plays a dual role, as both the photoredox catalyst for electron transfer and the cross-coupling catalyst for C-SCN bond formation.

4.
Org Biomol Chem ; 21(17): 3623-3627, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37066489

RESUMEN

An efficient biocatalytic reduction of difluoroalkyl ketones for accessing chiral fluoroalkyl secondary alcohols is reported using commercial NADPH-dependent ketoreductase K234 with 2-propanol as a co-substrate for NADPH regeneration. This bioreduction reaction could be applied to a broad range of prochiral fluoroketones including aryl difluoroketones, aliphatic difluoroketones, and trifluoroacetophenones with excellent conversion and favorable enantioselectivity at high substrate concentrations (100 g L-1). These results indicate the potential of K234 for the industrial production of valuable chiral fluorohydrins. Moreover, this biocatalytic protocol could also be effective without the addition of an external nicotinamide cofactor, which provides useful guidance for further application of ketoreductase K234 in the asymmetric synthesis of chiral secondary alcohols.

5.
J Exp Bot ; 74(12): 3749-3764, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-36964900

RESUMEN

The corn leaf aphid (Rhopalosiphum maidis) is a major maize pest that frequently causes substantial yield losses. Exploring the genetic basis of resistance to aphids is important for improving maize yield and quality. Here, we used a maize recombinant inbred line population derived from two parents with different susceptibility to aphids, B73 (susceptible) and Abe2 (resistant), and performed quantitative trait locus (QTL) mapping using aphid resistance scores as an indicator. We mapped a stable QTL, qRTA6, to chromosome 6 using data from 2 years of field trials, which explained 40.12-55.17% of the phenotypic variation. To further investigate the mechanism of aphid resistance in Abe2, we constructed transcriptome and metabolome libraries from Abe2 and B73 leaves with or without aphid infestation at different time points. Integrating QTL mapping and transcriptome data revealed three aphid resistance candidate genes (Zm00001d035736, Zm00001d035751, and Zm00001d035767) associated with the hypersensitive response, the jasmonic acid pathway, and protein ubiquitination. Integrated transcriptomic and metabolomic analysis revealed that the differentially expressed genes and metabolites were enriched in flavonoid biosynthesis. These findings extend our understanding of the molecular mechanisms controlling aphid resistance in maize, and the QTL and candidate genes are valuable resources for increasing this resistance.


Asunto(s)
Áfidos , Animales , Áfidos/fisiología , Zea mays/genética , Zea mays/metabolismo , Sitios de Carácter Cuantitativo , Multiómica , Hojas de la Planta/genética
6.
BMC Plant Biol ; 22(1): 328, 2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-35799118

RESUMEN

BACKGROUND: Flowering time is an important agronomic trait of crops and significantly affects plant adaptation and seed production. Flowering time varies greatly among maize (Zea mays) inbred lines, but the genetic basis of this variation is not well understood. Here, we report the comprehensive genetic architecture of six flowering time-related traits using a recombinant inbred line (RIL) population obtained from a cross between two maize genotypes, B73 and Abe2, and combined with genome-wide association studies to identify candidate genes that affect flowering time. RESULTS: Our results indicate that these six traits showed extensive phenotypic variation and high heritability in the RIL population. The flowering time of this RIL population showed little correlation with the leaf number under different environmental conditions. A genetic linkage map was constructed by 10,114 polymorphic markers covering the whole maize genome, which was applied to QTL mapping for these traits, and identified a total of 82 QTLs that contain 13 flowering genes. Furthermore, a combined genome-wide association study and linkage mapping analysis revealed 17 new candidate genes associated with flowering time. CONCLUSIONS: In the present study, by using genetic mapping and GWAS approaches with the RIL population, we revealed a list of genomic regions and candidate genes that were significantly associated with flowering time. This work provides an important resource for the breeding of flowering time traits in maize.


Asunto(s)
Estudio de Asociación del Genoma Completo , Zea mays , Mapeo Cromosómico/métodos , Ligamiento Genético , Estudio de Asociación del Genoma Completo/métodos , Fenotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Zea mays/genética
7.
Biosens Bioelectron ; 203: 114029, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35114469

RESUMEN

Insulin is an essential and versatile hormone taking part in the control of blood glucose levels and protein anabolism. Abnormal levels of circulating insulin in the body can be problematic. Insulin resistance means the body fails to react with high or normal level insulin, causing our body to produce more insulin through feedback, and is the main cause of many chronic diseases such as type 2 diabetes and obesity. Pre-diabetes or obesity often occurs in people with high insulin resistance. Thus, quantification of insulin levels is essential for the early diagnosis and treatment of diabetes mellitus and obesity. Immunoassays and chromatography assays are currently reliable methods for insulin detection, although they are time-consuming, expensive, and require complex procedures, centralized instruments as well as trained personnel. Modern biosensing technologies have demonstrated success and huge potential for the quantification of insulin. This review provides a summary of the biological significance of insulin with a focus on the role of insulin resistance and its consequences in pre-diabetes/diabetes and obesity. The current practice for insulin detection followed by recent advances in developing biosensors for detection of insulin are reviewed, compared, and discussed from the aspects of detection principle, analytical performances, and challenges. Finally, future perspectives in the quantification of insulin in clinical settings are proposed.


Asunto(s)
Técnicas Biosensibles , Diabetes Mellitus Tipo 2 , Estado Prediabético , Glucemia/análisis , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Diagnóstico Precoz , Humanos , Insulina , Estado Prediabético/diagnóstico , Estado Prediabético/metabolismo
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