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1.
Opt Express ; 31(24): 39953-39964, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041307

RESUMO

We propose the coupling of multiple quantum wells and surface plasmons can improve coherence of light emitted from LED wafers, as evidenced herein by a shallow-etched conic pit array with evaporated Ag (V-Ag) on a GaN-based LED wafer. The improvement in spatial coherence is critically verified by angle-resolved spectra. The temporal coherence length of the V-Ag wafer is 1.4 times larger than that of the plain wafer. The coherence-enhanced wafer achieves anisotropic and deflective emission in micro area and at far field by diffraction. This research provides a novel perspective on research of plasmonic LEDs and a new straightforward architecture to acquire partially coherent light from LEDs.

2.
Opt Express ; 28(24): 35708-35715, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379681

RESUMO

We design, fabricate and analyze plasmon-enhanced LEDs with the tapered Ag structure that significantly increases plasmonic coupling efficiency at a coupling distance far beyond the penetration depth. The electroluminescence intensity showed a 16-fold increase compared with planar LEDs with a coupling distance of 100 nm. The enhanced coupling efficiency with large distance is originated from the accumulated SP energy at the metal conical tip and the missing momentum provided by the corrugated surface. Therefore, the SP-enhanced LED with tapered Ag structure can maintain a high luminous efficiency and a stable working state even with thick p-GaN layer, which also guarantees a high electrical performance. Our study paves the way for a practical implementation of SP-enhanced LEDs with excellent optical and electrical properties.

3.
Biomed Mater ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498946

RESUMO

Osteosarcoma is a rare cancer affecting disease for children and young adults; complete healing from this condition is quite difficult. Recently, new regeneration materials have been preferred, including natural compound companied implants for affected bone repair, and it is effectively used to treat osteosarcoma disease. Hence, Octa calcium phosphate (OCP) reinforced with poly (vinyl alcohol) (PVA) and oleic acid (OA) with Naringenin (NRG) composite was prepared and studied to cure the sarcoma affected bone. The physicochemical nature of the prepared OCP, PVA/OA/OCP, and PVA/OA/OCP/NRG composite were characterized by FT-IR, SEM, and XRD techniques. The in vitro release of the NRG from the PVA/OA/OCP/NRG composite was evaluated by UV-visible spectroscopy and the NRG release rate was observed at 98.0 % over 24 h. Biocompatibility and cell viability of the prepared OCP, PVA/OA/OCP, and PVA/OA/OCP/NRG composite are investigated in adipose-derived stem cells (ASCs) on different days. Interestingly, the PVA/OCP/OA/NRG composite shows an increase of 74.0 % to 92.0 % in cell survival, indicating that the composite is biocompatible. Similarly, the ability of NRG in the composite is to suppress cancer cells and it was determined in lung cancer (A549) cells. NRG-loaded PVA/OCP/OA/NRG shows good inhibition ability, nearly 43 % at 72 h. From the results, the prepared composite materials can inhibit cancer cells and be viable in stem cell growth. Since the materials will serve as potential regenerative materials for sarcoma-affected bone recovery.

4.
Talanta ; 217: 121020, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32498838

RESUMO

Rapid quantification of pathogenic Salmonella Typhimurium (S. Typhimurium) and total bacteria in eggs is highly desired for food safety control. However, the complexity of egg matrix presents a significant challenge for sensitive detection of bacteria. In this study, a sample pretreatment protocol, including dilution, fat dissolution, protein degradation, filtration, and washing was developed to circumvent this challenge. A laboratory-built nano-flow cytometer (nFCM) that is hundreds of fold more sensitive than the conventional flow cytometer was employed to analyze individual bacteria upon nucleic acid and immunofluorescent staining. Eggs spiked with pathogenic S. Typhimurium and harmless Escherichia coli K12 (E. coli K12) were used as the model system to optimize the sample pretreatment protocol. S. Typhimurium and total bacteria in eggs can be quantified without cultural enrichment, and the whole process of sample pretreatment, staining, and instrument analysis can be accomplished within 1.5 h. The bacterial recovery rate upon sample pretreatment, detection limit, and dynamic range for S. Typhimurium in eggs were 92%, 2 × 103 cells/mL, and from 2 × 103 to 4 × 108 cells/mL, respectively. The as-developed approach can specifically distinguish S. Typhimurium from other bacteria and successful application to bacterial detection in eggs freshly purchased from supermarket and spoiled eggs upon inappropriate storage was demonstrated.


Assuntos
Ovos/microbiologia , Citometria de Fluxo , Nanotecnologia , Salmonella typhimurium/isolamento & purificação , Escherichia coli K12/isolamento & purificação
5.
Mol Ecol Resour ; 19(5): 1278-1291, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30375755

RESUMO

Intensification of inland fisheries and aquatic landscape conversion led to a drastic decline of fish populations in the Yangtze River (YR) during the last decades. This situation urges for the development of a large-scale molecular assessment of YR ichthyofauna to further develop standardized methods of molecular identification for conservation and fisheries management purposes. We present here the results of a large-scale campaign to DNA barcode YR freshwater fishes that succeeded in producing 1,424 new DNA barcodes for 123 species. Together with 1,406 sequences mined from BOLD and GenBank, a reference library including 2,830 DNA barcodes for 238 species was compiled. By using four DNA-based species delimitation methods, RESL, ABGD, mPTP and mGMYC, 230 operational taxonomic units (OTUs) were identified and 195 species displayed OTUs that tightly match species boundaries. No barcoding gap was observed; however, and conflicting cases of species and OTU delimitation were identified. A total of 23 species with maximum intraspecific distances above 2% were detected and null genetic distances to the nearest phylogenetic relatives were detected in 11 species. Among those 23 species, 16 were represented by multiple OTUs amounting to 40 OTUs delineated. Several cases of multiple OTUs confined to species boundaries were detected suggesting the presence of overlooked species. A total of 18 OTUs, however, were shared by several species and particularly so for the Qinghai-Tibet plateau endemic species. These results are discussed with reference to previous large-scale DNA barcoding campaign and compared to previous phylogeographic studies in the YR.


Assuntos
Biota , Código de Barras de DNA Taxonômico , Peixes/classificação , Peixes/genética , Rios , Animais , China , Filogeografia
6.
Zootaxa ; 4126(2): 295-300, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27395590

RESUMO

A new species of the genus Garra is described from the Longchuan Jiang River, a tributary flowing to the Yiluowadi Jiang (Irrawaddy River) basin in Tengchong, Yunnan, South China. Garra longchuanensis is distinct from other Chinese congeners, except for G. qiaojiensis, in having 12 circumpeduncular scales, a well-developed rostral lobe with irregular distributed acanthoid tubercles, a deep groove to form a transverse lobe and a conspicuous, heavily tuberculated quadrate proboscis, and from G. qiaojiensis in having a slightly pointed snout (vs. rounded), a long and slender caudal peduncle (length 17.8-20.6% SL vs. 15.5-17.1%, width 10.9-12.6% SL vs. 11.3-12.6%), pectoral fin with 15-16 (vs. 13) branched rays, pelvic fin with 9 (vs. 8) branched rays, and an anterior position of anus (anus to anal distance 27.2-39.1% of pelvic to anal distance vs. 22.8-28.3%).


Assuntos
Cyprinidae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , China , Cyprinidae/anatomia & histologia , Cyprinidae/crescimento & desenvolvimento , Tamanho do Órgão , Rios/química
7.
Mol Phylogenet Evol ; 46(3): 818-29, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18203625

RESUMO

The family Cyprinidae is the largest freshwater fish group in the world, including over 200 genera and 2100 species. The phylogenetic relationships of major clades within this family are simply poorly understood, largely because of the overwhelming diversity of the group; however, several investigators have advanced different hypotheses of relationships that pre- and post-date the use of shared-derived characters as advocated through phylogenetic systematics. As expected, most previous investigations used morphological characters. Recently, mitochondrial DNA (mtDNA) sequences and combined morphological and mtDNA investigations have been used to explore and advance our understanding of species relationships and test monophyletic groupings. Limitations of these studies include limited taxon sampling and a strict reliance upon maternally inherited mtDNA variation. The present study is the first endeavor to recover the phylogenetic relationships of the 12 previously recognized monophyletic subfamilies within the Cyprinidae using newly sequenced nuclear DNA (nDNA) for over 50 species representing members of the different previously hypothesized subfamily and family groupings within the Cyprinidae and from other cypriniform families as outgroup taxa. Hypothesized phylogenetic relationships are constructed using maximum parsimony and Basyesian analyses of 1042 sites, of which 971 sites were variable and 790 were phylogenetically informative. Using other appropriate cypriniform taxa of the families Catostomidae (Myxocyprinus asiaticus), Gyrinocheilidae (Gyrinocheilus aymonieri), and Balitoridae (Nemacheilus sp. and Beaufortia kweichowensis) as outgroups, the Cyprinidae is resolved as a monophyletic group. Within the family the genera Raiamas, Barilius, Danio, and Rasbora, representing many of the tropical cyprinids, represent basal members of the family. All other species can be classified into variably supported and resolved monophyletic lineages, depending upon analysis, that are consistent with or correspond to Barbini and Leuciscini. The Barbini includes taxa traditionally aligned with the subfamily Cyprininae sensu previous morphological revisionary studies by Howes (Barbinae, Labeoninae, Cyprininae and Schizothoracinae). The Leuciscini includes six other subfamilies that are mainly divided into three separate lineages. The relationships among genera and subfamilies are discussed as well as the possible origins of major lineages.


Assuntos
Cyprinidae/genética , Cipriniformes/genética , Filogenia , Proteínas Ribossômicas/genética , Animais , Núcleo Celular/genética , Cyprinidae/classificação , Cipriniformes/classificação , Variação Genética , Íntrons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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