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1.
Nanoscale Adv ; 3(14): 4286-4291, 2021 Jul 13.
Article in English | MEDLINE | ID: mdl-36132839

ABSTRACT

Plasmon resonances with high-quality are of great importance in light emission control and light-matter interactions. Nevertheless, inherent ohmic and radiative losses usually hinder the plasmon performance of metallic nanostructures, especially for aluminum (Al). Here we demonstrate a Bragg grating decorated nanodisk to narrow the linewidth of breathing plasmon resonances compared with a commensurate nanodisk. Two kinds of plasmon resonant modes and the corresponding mode patterns are investigated in cathodoluminescence (CL) depending on the different electron bombardment positions, and the experimental results agree well with full wave electromagnetic simulations. Linewidth narrowing can be clearly understood using an approximated magnetic dipole model. Our results suggest a feasible mechanism for linewidth narrowing of plasmon resonances as well as pave the way for in-depth analysis and potential applications of Al plasmon systems.

2.
Front Plant Sci ; 12: 772655, 2021.
Article in English | MEDLINE | ID: mdl-35058947

ABSTRACT

Retrotransposons are the most abundant group of transposable elements (TEs) in plants, providing an extraordinarily versatile source of genetic variation. Thlaspi arvense, a close relative of the model plant Arabidopsis thaliana with worldwide distribution, thrives from sea level to above 4,000 m elevation in the Qinghai-Tibet Plateau (QTP), China. Its strong adaptability renders it an ideal model system for studying plant adaptation in extreme environments. However, how the retrotransposons affect the T. arvense genome evolution and adaptation is largely unknown. We report a high-quality chromosome-scale genome assembly of T. arvense with a scaffold N50 of 59.10 Mb. Long terminal repeat retrotransposons (LTR-RTs) account for 56.94% of the genome assembly, and the Gypsy superfamily is the most abundant TEs. The amplification of LTR-RTs in the last six million years primarily contributed to the genome size expansion in T. arvense. We identified 351 retrogenes and 303 genes flanked by LTRs, respectively. A comparative analysis showed that orthogroups containing those retrogenes and genes flanked by LTRs have a higher percentage of significantly expanded orthogroups (SEOs), and these SEOs possess more recent tandem duplicated genes. All present results indicate that RNA-based gene duplication (retroduplication) accelerated the subsequent tandem duplication of homologous genes resulting in family expansions, and these expanded gene families were implicated in plant growth, development, and stress responses, which were one of the pivotal factors for T. arvense's adaptation to the harsh environment in the QTP regions. In conclusion, the high-quality assembly of the T. arvense genome provides insights into the retroduplication mediated mechanism of plant adaptation to extreme environments.

3.
Colloids Surf B Biointerfaces ; 175: 26-35, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30513471

ABSTRACT

Biocompatible and highly porous network hydrogel scaffolds were fabricated for the development of artificial cornea (AC) periphery/skirt that could be used to enhance the long-term retention of the implants. In this study, a series of hydrogel scaffolds for this application was fabricated from the photo-polymerization of a mixture of poly(ethylene glycol) (PEG)- and poloxamer (P407)-based macromer solutions in dichloromethane in which solvent-induced phase separation (SIPS) arose to form scaffolds with macroporous structure and high water content. The overall porosity ranging from 20% to 75% and open/closed pore structure of the hydrogel scaffolds could be finely tuned by varying the ratio of P407/PEG in the macromer solution and solvent type. The total porosity and open-cell structure of the macropores in the synthesized hydrogel scaffolds affected the swelling behavior, dynamic properties such as the storage moduli of the hydrogels as well as their degradation rates. Based on the subcutaneous implantation in rats, superporous hydrogel scaffolds induced the formation of thinner fibrous capsules around the implants and showed less inflammatory reaction, suggesting that the hydrogel scaffolds made from SIPS exhibited good cytocompatibility. The combined results of swelling ratio, porosity, physical strength and subcutaneous implant tests indicated that the superporous hydrogels with porosity >50% showed potentials to be used for cornea periphery application.


Subject(s)
Biocompatible Materials/chemistry , Hydrogels/chemistry , Poloxamer/chemistry , Polyethylene Glycols/chemistry , Animals , Artificial Organs , Biocompatible Materials/administration & dosage , Cornea/cytology , Cornea/drug effects , Cornea/physiology , Hydrogels/administration & dosage , Microscopy, Electron, Scanning , Porosity , Rats, Wistar , Tissue Engineering , Tissue Scaffolds/chemistry
4.
Lung Cancer ; 119: 56-63, 2018 05.
Article in English | MEDLINE | ID: mdl-29656753

ABSTRACT

INTRODUCTION: Histological subtypes of lung adenocarcinomas (ADCs) classified by the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) system have been investigated using radiomic approaches. However, the results have had limitations since <80% of invasive lung ADCs were heterogeneous, with two or more subtypes. To reduce the influence of heterogeneity during radiomic analysis, computed tomography (CT) images of lung ADCs with near-pure ADC subtypes were analyzed to extract representative radiomic features of different subtypes. METHODS: We enrolled 95 patients who underwent complete resection for lung ADC and a pathological diagnosis of a "near-pure" (≥70%) IASLC/ATS/ERS histological subtype. Conventional histogram/morphological features and complex radiomic features (grey-level-based statistical features and component variance-based features) of thin-cut CT data of tumor regions were analyzed. A prediction model based on leave-one-out cross-validation (LOOCV) and logistic regression (LR) was used to classify all five subtypes and three pathologic grades (lepidic, acinar/papillary, micropapillary/solid) of ADCs. The validation was performed using 36 near-pure ADCs in a later cohort. RESULTS: A total of 31 lepidic, 14 papillary, 32 acinar, 10 micropapillary, and 8 solid ADCs were analyzed. With 21 conventional and complex radiomic features, for 5 subtypes and 3 pathological grades, the prediction models achieved accuracy rates of 84.2% (80/95) and 91.6% (87/95), respectively, while accuracy was 71.6% and 85.3%, respectively, if only conventional features were used. The accuracy rate for the validation set (n = 36) was 83.3% (30/36) and 94.4% (34/36) in 5 subtypes and 3 pathological grades, respectively, using conventional and complex features, while it was 66.7% and 77.8% only using conventional features, respectively. CONCLUSION: Lung ADC with high purity pathological subtypes demonstrates strong stratification of radiomic values, which provide basic information for accurate pathological subtyping and image parcellation of tumor sub-regions.


Subject(s)
Adenocarcinoma of Lung/pathology , Lung Neoplasms/pathology , Lung/pathology , Adenocarcinoma of Lung/diagnosis , Adenocarcinoma of Lung/mortality , Cohort Studies , Europe , Humans , Lung/diagnostic imaging , Lung Neoplasms/diagnosis , Lung Neoplasms/mortality , Neoplasm Staging , Pneumonectomy , Retrospective Studies , Societies, Medical , Survival Analysis , Tomography, X-Ray Computed , United States
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