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1.
ACS Nano ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916440

RESUMO

Colloidal nanoparticles offer unique photoelectric properties, making them promising for functional applications. Multiparticle systems exhibit synergistic effects on the functional properties of their individual components. However, precisely controlled assembly of multiparticles to form patterned building blocks for solid-state devices remains challenging. Here, we demonstrate a versatile multiparticle synergistic electrophoretic deposition (EPD) strategy to achieve controlled assembly, high-efficiency, and high-resolution patterns. Through elaborate surface design and charge regulation of nanoparticles, we achieve precise control over the particle distribution (gradient or homogeneous structure) in multiparticle films using the EPD technique. The multiparticle system integrates silicon oxide and titanium oxide nanoparticles, synergistically enhancing the emission efficiency of quantum dots to a high level in the field. Furthermore, we demonstrate the superiority of our strategy to integrate multiparticle into large-area full-color display panels with a high resolution over 1000 pixels per inch. The results suggest great potential for developing multiparticle systems and expanding diverse functional applications.

2.
Polymers (Basel) ; 16(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38931982

RESUMO

Recycling flexible polyurethane foam (F-PUF) scraps is difficult due to the material's high cross-linking structure. In this work, a wedge-block-reinforced extruder with a considerable enhanced shear extrusion and stretching area between the rotating screw and the stationary wedge blocks was utilized to recycle F-PUF scraps into powder containing surface-active hydroxyl groups. The powder was then utilized for the quantitative replacement of polyol in the foaming process. Characterizations showed that the continuous shear extrusion and stretching during the extrusion process reduced the volume mean diameter (VMD) of the F-PUF powder obtained by extruding it three times at room temperature to reach 54 µm. The -OH number (OHN) of the powder prepared by extruding it three times reached 19.51 mgKOH/g due to the mechanochemical effect of the powdering method. The F-PUF containing recycled powder used to quantitively replace 10 wt.% polyol was similar in microstructure and chemical structure to the original F-PUF, with a compression set of 2%, indentation load deflection of 21.3 lbf, resilience of 43.4%, air permeability of 815.7 L/m2·s, tensile strength of 73.0 Kpa, and tear strength of 2.3 N/cm, indicating that the recycling method has potential for industrial applications.

3.
Front Neurol ; 15: 1367974, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638307

RESUMO

Corona Virus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has presented unprecedented challenges to the world. Changes after acute COVID-19 have had a significant impact on patients with neurodegenerative diseases. This study aims to explore the mechanism of neurodegenerative diseases by examining the main pathways of central nervous system infection of SARS-CoV-2. Research has indicated that chronic inflammation and abnormal immune response are the primary factors leading to neuronal damage and long-term consequences of COVID-19. In some COVID-19 patients, the concurrent inflammatory response leads to increased release of pro-inflammatory cytokines, which may significantly impact the prognosis. Molecular imaging can accurately assess the severity of neurodegenerative diseases in patients with COVID-19 after the acute phase. Furthermore, the use of FDG-PET is advocated to quantify the relationship between neuroinflammation and psychiatric and cognitive symptoms in patients who have recovered from COVID-19. Future development should focus on aggressive post-infection control of inflammation and the development of targeted therapies that target ACE2 receptors, ERK1/2, and Ca2+.

4.
Polymers (Basel) ; 16(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337284

RESUMO

Low-temperature mechanical chemical devulcanization is a process that can produce reclaimed rubber with exceptional mechanical properties. However, the inadequacy and low efficiency of the devulcanization have significantly restricted its application. To address the issues, alcoholic amines, including hydroxyethyl ethylenediamine (AEEA), ethanolamine (ETA), and diethanol amine (DEA), are utilized as devulcanizing agents to promote the devulcanization process. Careful characterizations are conducted to reveal the devulcanizing mechanism and to depict the performances of reclaimed rubbers. Results show that the amine groups in the devulcanizing agents can react with sulfur after the crosslink bonds are broken by mechanical shear force, thus blocking the activity of sulfur and introducing hydroxyl groups into the rubber chains. The incorporation of alcoholic amines can enhance the devulcanizing degree and devulcanizing efficiency, reduce the Mooney viscosity, and improve the mechanical and anti-aging performance. When using DEA as the devulcanizing agent, the sol content of reclaimed rubber increases from 13.1% to 22.4%, the devulcanization ratio increases from 82.1% to 89.0%, the Mooney viscosity decreases from 135.5 to 83.6, the tensile strength improves from 14.7 MPa to 16.3 MPa, the retention rate of tensile strength raises from 55.2% to 82.6% after aging for 72 h, while the devulcanization time is shortened from 21 min to 9.5 min, compared with that without using alcoholic amines. Therefore, alcoholic amines exhibit remarkable advantages in the devulcanization of waste rubber, thus indicating a promising direction for the advancement of research in the area of waste rubber reclamation.

5.
Polymers (Basel) ; 15(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36771778

RESUMO

Carbon nanotube (CNT), as reinforcing agents in natural rubber (NR), has gained a large amount of consideration due to their excellent properties. Uniform dispersion of CNT is the key to obtaining high-performance NR nanocomposites. In this contribution, a novel ultrasonic grinding dispersion method of CNT with waterjet-produced rubber powder (WPRP) as a carrier is proposed. Microscopic morphologies show that a Xanthium-like structure with WPRP as the core and CNTs as the spikes is formed, which significantly improves the dispersion of CNT in the NR matrix and simultaneously strengthens the bonding of the WPRP and NR matrix. With the increase in the WPRP loading, the Payne effect of CNT/WPRP/NR composites decreases, indicating the effectiveness of the dispersion method. The vulcanization MH and ML value and crosslinking density increase with the increase in the WPRP loading, whereas the scorch time and cure time exhibit a decreasing trend when the WPRP loading is less than 15 phr. It is found that the CNT/WPRP/NR composites filled with 5 phr WPRP have a 4% increase in 300% modulus, a 3% increase in tensile strength, while a 5% decrease in Akron abrasion loss, compared to CNT/NR composites.

6.
Gut Microbes ; 14(1): 2125747, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36128620

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is a highly heterogeneous psychiatric disorder that can have three phenotypical presentations: inattentive (I-ADHD), hyperactive-impulsive (HI-ADHD), and combined (C-ADHD). Environmental factors correlated with the gut microbiota community have been implicated in the development of ADHD. However, whether different ADHD symptomatic presentations are associated with distinct microbiota compositions and whether patients could benefit from the correction of aberrant bacterial colonization are still largely unclear. We carried out metagenomic shotgun analysis with 207 human fecal samples to characterize the gut microbial profiles of patients with ADHD grouped according to their phenotypical presentation. Then, we transplanted the candidate low-abundance bacteria identified in patient subgroups into ADHD rats and evaluated ADHD-associated behaviors and neuronal activation in these rats. Patients with C-ADHD had a different gut microbial composition from that of healthy controls (HCs) (p = .02), but not from that of I-ADHD patients. Eight species became progressively attenuated or enriched when comparing the compositions of HCs to those of I-ADHD and C-ADHD; in particular, the abundance of Bacteroides ovatus was depleted in patients with C-ADHD. In turn, Bacteroides ovatus supplementation ameliorated spatial working memory deficits and reversed θ electroencephalogram rhythm alterations in ADHD rats. In addition, Bacteroides ovatus induced enhanced neuronal activation in the hippocampal CA1 subregion. These findings indicate that gut microbial characteristics that are unique to patients with C-ADHD may be masked when considering a more heterogeneous group of patients. We link the gut microbiota to brain function in an ADHD animal model, suggesting the relevance of testing a potential bacteria-based intervention for some aspects of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Disfunção Cognitiva , Microbioma Gastrointestinal , Animais , Transtorno do Deficit de Atenção com Hiperatividade/microbiologia , Bacteroides , Cognição , Microbioma Gastrointestinal/fisiologia , Humanos , Ratos
7.
Ann Transl Med ; 10(10): 550, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35722362

RESUMO

Background: Thromboelastography (TEG) can dynamically evaluate the interaction between platelets and coagulation cascade and the effects of other cellular components on the activities of plasma factors, to comprehensively analyze the whole process of blood coagulation and dissolution. Due to differences in both the incidence rates and the coagulation state of related diseases, many studies have highlighted the necessity of establishing the normal reference ranges for TEG for local regions. The aim of the present study was to determine the local normal reference ranges according to the TEG results of 17,708 volunteers in Beijing, to explore the coagulation characteristics related to the age and sex of the study population. Methods: Reference ranges of reaction time (R), coagulation time (K), coagulation angle (α-angle), and maximum thrombus consistency (MA) for TEG in healthy adults in Beijing were determined in the physical examination of 17,708 Beijing volunteers (5,319 women and 12,389 men). The volunteers were divided into the elderly group (≥60 years old) and young and middle-aged group (20-59 years old), and the reference ranges of each group were calculated according to sex. Results: Based on the TEG results of the 17,708 volunteers who underwent physical examination, the 95% reference ranges of R, K, α-angle, and MA for TEG in Beijing were 5.1-10 min, 1.3-3.8 min, 44.9-70.2°, and 50.4-71 min, respectively. The results of R, K, α-angle, and MA for TEG between the young and middle-aged group and the elderly group, as well as between women and men were significantly different (P<0.001). Finally, reference ranges for TEG in the young and middle-aged group and the elderly group were obtained. Conclusions: Compared with the reference standards provided by previous reagent manufacturers, the coagulation factor and fibrinogen function of TEG tend to be hypocoagulable in Beijing population. We found that the young and middle-aged group had lower coagulation activity than the elderly group, and women had higher coagulation activity than men in the same group.

8.
Small ; 18(26): e2107629, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35615935

RESUMO

Electrophoretic deposition (EPD) is a facile technique to deposit quantum dots (QDs) films, which can be used as the color conversion layers for display applications. To better understand the EPD process, researchers have built many models of the EPD process. However, most of these models lack solid experimental support. Here, by adopting simple yet effective solvent engineering and well-designed experiments, this study proves the Cordelair-Greil model on EPD processes. Moreover, some supplements about this model are made according to practical experiments. The experimental verification of the Cordelair-Greil model is a solid step toward revealing the dynamics of the EPD process. Furthermore, the formation of cracks in EPD deposited QD films is prevented through solvent engineering. This work proves that besides modifying the intrinsic properties of QDs, solvent engineering is also a simple, effective, and low-cost way to study the EPD process and improve the QD film qualities deposited.


Assuntos
Pontos Quânticos , Eletroforese/métodos , Solventes
9.
Oxid Med Cell Longev ; 2021: 9465300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336120

RESUMO

Aging augments postischemic apoptosis via incomplete mechanisms. Our previous animal study suggests that in addition to proapoptotic effects, lncRNAs also exert antiapoptotic effects in cardiomyocytes. However, whether this unexpected phenomenon exists in humans is unknown. In the present study, we investigated the relationship between aging and apoptosis regulation in human blood samples and confirmed their role by utilizing the cardiomyocyte lines (AC16 cells). Human blood samples were collected from 20 pairs of older adult and young volunteers. Age-different apoptotic regulatory lncRNAs and miRNAs were identified by microarray and bioinformatics analysis. The results indicated that lncRNA (NONHSAT069381 and NONHSAT140844) and miRNA (hsa-miR-124-5p and hsa-miR-6507-5p) were increased in aging human blood, confirmed by both bioinformatics analysis and polymerase chain reaction (PCR). Overexpression of NONHSAT069381 in AC16 cells increased caspase-3 levels and increased cardiomyocyte apoptotic cell death (determined by TUNEL staining and caspase activity assays) after hypoxia/reoxygenation (H/R), while overexpression of NONHSAT140844 increased X-chromosome-linked inhibitor of apoptosis protein (XIAP) content and decreased the myocardial apoptotic cell death. Furthermore, luciferase reporter assay revealed that hsa-miR-124-5p might be a mediator between NONHSAT069381 and mCASP3 and hsa-miR-6507-5p might be a mediator between NONHSAT140844 and mXIAP. Overexpression of hsa-miR-124-5p decreased caspase-3 levels and overexpression of hsa-miR-6507-5p decreased XIAP content in AC16 cells. We have found evidence that lncRNAs are important regulatory molecules in aging-mediated effects upon apoptosis. More interestingly, besides apoptosis-promoting effects, aging also inhibits myocardial apoptosis after H/R. This phenomenon also exists in the human cardiomyocyte line.


Assuntos
Apoptose/genética , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Idoso , Envelhecimento , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Transfecção
10.
Nat Commun ; 12(1): 4603, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326332

RESUMO

Colloidal quantum dot (QD) emitters show great promise in the development of next-generation displays. Although various solution-processed techniques have been developed for nanomaterials, high-resolution and uniform patterning technology amicable to manufacturing is still missing. Here, we present large-area, high-resolution, full-color QD patterning utilizing a selective electrophoretic deposition (SEPD) technique. This technique utilizes photolithography combined with SEPD to achieve uniform and fast fabrication, low-cost QD patterning in large-area beyond 1,000 pixels-per-inch. The QD patterns only deposited on selective electrodes with precisely controlled thickness in a large range, which could cater for various optoelectronic devices. The adjustable surface morphology, packing density and refractive index of QD films enable higher efficiency compared to conventional solution-processed methods. We further demonstrate the versatility of our approach to integrate various QDs into large-area arrays of full-color emitting pixels and QLEDs with good performance. The results suggest a manufacture-viable technology for commercialization of QD-based displays.

11.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753478

RESUMO

Species in a shared environment tend to evolve similar adaptations under the influence of their phylogenetic context. Using snowfinches, a monophyletic group of passerine birds (Passeridae), we study the relative roles of ancestral and species-specific adaptations to an extreme high-elevation environment, the Qinghai-Tibet Plateau. Our ancestral trait reconstruction shows that the ancestral snowfinch occupied high elevations and had a larger body mass than most nonsnowfinches in Passeridae. Subsequently, this phenotypic adaptation diversified in the descendant species. By comparing high-quality genomes from representatives of the three phylogenetic lineages, we find that about 95% of genes under positive selection in the descendant species are different from those in the ancestor. Consistently, the biological functions enriched for these species differ from those of their ancestor to various degrees (semantic similarity values ranging from 0.27 to 0.5), suggesting that the three descendant species have evolved divergently from the initial adaptation in their common ancestor. Using a functional assay to a highly selective gene, DTL, we demonstrate that the nonsynonymous substitutions in the ancestor and descendant species have improved the repair capacity of ultraviolet-induced DNA damage. The repair kinetics of the DTL gene shows a twofold to fourfold variation across the ancestor and the descendants. Collectively, this study reveals an exceptional case of adaptive evolution to high-elevation environments, an evolutionary process with an initial adaptation in the common ancestor followed by adaptive diversification of the descendant species.


Assuntos
Aclimatação/genética , Tamanho Corporal/genética , Taxa de Mutação , Seleção Genética , Altitude , Substituição de Aminoácidos , Animais , Reparo do DNA , Proteínas Nucleares/genética , Filogenia , Especificidade da Espécie , Tibet
12.
J Adv Nurs ; 76(10): 2709-2718, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32749027

RESUMO

AIM: To evaluate the effect of an 8-week humour intervention programme on reducing depression and anxiety and improving subjective well-being, cognitive function and sleep quality in nursing home residents. DESIGN: A single-blinded and quasi-experimental design with repeated measures. METHODS: Seventy-four older adults were recruited from May 2018-September 2018, with 37 older adults in the humour group received humour intervention and 37 in the control group received no intervention. The intervention was an 8-week humour intervention programme for older adults to learn to use humour and release their emotions. Primary outcomes include depression, anxiety and subjective well-being and secondary outcomes were cognitive function and sleep quality. Two-way repeated measures ANOVA was used to compare the differences of outcome measures between the two groups. Outcomes were measured at baseline, 8 and 16 weeks. RESULTS: There was no significant difference between the two groups at baseline. The adherence to the sessions of humour intervention over the 8-weeks was 97.6%. Two-way repeated measures ANOVA revealed significant improvement in depression, anxiety, subjective well-being and sleep quality during the postintervention (8 weeks) and follow-up (16 weeks) periods in the humour group versus the control group. However, a significant time × group interaction for cognitive function was only found during postintervention. CONCLUSION: The humour intervention programme was effective in reducing depression and anxiety symptoms and increasing subjective well-being, cognitive function and sleep quality in older adults. IMPACT: Physical and mental health problems are common among older adults in nursing homes. The study demonstrated that humour intervention has feasibility and potential to be used as an effective non-pharmacological intervention in improving well-beings of Chinese nursing home residents. TRIAL REGISTRATION: ChiCTR1800016148.


Assuntos
Ansiedade , Depressão , Idoso , Ansiedade/prevenção & controle , China , Cognição , Depressão/prevenção & controle , Humanos , Casas de Saúde , Sono
13.
Adv Mater ; 32(29): e2001999, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32510677

RESUMO

Halide perovskites have shown tremendous potential for next-generation flat-panel laser displays due to their remarkable optoelectronic properties and outstanding material processability; however, the lack of a general approach for the fast growth of perovskite laser arrays capable of electrical operations impedes actualization of their display applications. Herein, a universal and robust wettability-guided screen-printing technique is reported for the rapid growth of large-scale multicolor perovskite microdisk laser arrays, which can serve as laser display panels and further be used to realize current-driven displays. The perovskite microlasers are precisely defined with controlled physical dimensions and spatial locations by such a printing strategy, and each perovskite microlaser serves as a pixel of a display panel. Moreover, the screen-printing procedure is highly compatible with light-emitting diode (LED) device architectures, which is favorable for the mass production of micro-LED arrays. On this basis, a prototype of a current-driven display is demonstrated with desired functionalities. The outstanding performance and feasible fabrication of screen-printed perovskite microlaser arrays embedded in LEDs provide deep insights into the concepts and device architectures of electrically driven laser display technology.

14.
Angew Chem Int Ed Engl ; 59(29): 11814-11818, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32270893

RESUMO

A universal approach is demonstrated for realizing dual-wavelength lasing in organic core-shell structured microlaser arrays, which show great promise in serving as all-color laser display panels. By alternately printing hydrophilic and hydrophobic laser dye solutions on preprocessed substrates, precisely patterned core-shell heterostructure arrays were obtained. The spatially separated core and shell independently function as optical resonators to support dual-wavelength tunable lasing in each heterostructure. Such a general method enables to flexibly control the lasing wavelength of the core-shell microlasers across a wide spectral range by systematically designing the gain media. Using as-prepared microlaser arrays as display panels, full-color laser displays were achieved with a color gamut much larger than that of standard RGB space. These results provide insights for design concepts and device construction for novel optoelectronic applications.

15.
Natl Sci Rev ; 7(1): 113-127, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34692022

RESUMO

Known as the 'third polar region', the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment.

16.
Nat Commun ; 10(1): 870, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30787345

RESUMO

Laser displays, which exploit characteristic advantages of lasers, represent a promising next-generation display technology based on the ultimate visual experience they provide. However, the inability to obtain pixelated laser arrays as self-emissive full-color panels hinders the application of laser displays in the flat-panel sector. Due to their excellent optoelectronic properties and processability, organic materials have great potential for the production of periodically patterned multi-color microlaser arrays. Here, we demonstrate for the first time full-color laser displays on precisely patterned organic red-green-blue (RGB) microlaser matrices through inkjet printing. Individual RGB laser pixels are realized by doping respective luminescent dyes into the ink materials, resulting in a wide achievable color gamut 45% larger than the standard RGB space. Using as-prepared microlaser arrays as full-color panels, we achieve dynamic laser displays for video playing through consecutive beam scanning. These results represent a major step towards full-color laser displays with outstanding color expression.

17.
Nat Plants ; 5(2): 174-183, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30692677

RESUMO

Snapdragon (Antirrhinum majus L.), a member of the Plantaginaceae family, is an important model for plant genetics and molecular studies on plant growth and development, transposon biology and self-incompatibility. Here we report a near-complete genome assembly of A. majus cultivar JI7 (A. majus cv.JI7) comprising 510 Megabases (Mb) of genomic sequence and containing 37,714 annotated protein-coding genes. Scaffolds covering 97.12% of the assembled genome were anchored on eight chromosomes. Comparative and evolutionary analyses revealed that a whole-genome duplication event occurred in the Plantaginaceae around 46-49 million years ago (Ma). We also uncovered the genetic architectures associated with complex traits such as flower asymmetry and self-incompatibility, identifying a unique duplication of TCP family genes dated to around 46-49 Ma and reconstructing a near-complete ψS-locus of roughly 2 Mb. The genome sequence obtained in this study not only provides a representative genome sequenced from the Plantaginaceae but also brings the popular plant model system of Antirrhinum into the genomic age.


Assuntos
Antirrhinum/genética , Genoma de Planta , Proteínas de Plantas/genética , Evolução Biológica , Flores/anatomia & histologia , Flores/genética , Flores/fisiologia , Duplicação Gênica , Anotação de Sequência Molecular , Filogenia , Autoincompatibilidade em Angiospermas/genética
18.
Nano Lett ; 18(2): 1241-1245, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29323922

RESUMO

Miniaturized lasers with high spectra purity and switchable output are of crucial importance for various ultracompact photonic devices. However, it still remains a great challenge to simultaneously control the wavelength and mode purity of microscale lasers due to the insensitive response of traditional materials to external stimuli. In this work, we propose a strategy to realize switchable single-mode microlasers in perovskite microwires (MWs) coupled with responsive organic microdisk cavities. The perovskite MW therein serves as an excellent laser source to deliver multiple lasing modes, while the microdisk functions as a spectral filter to achieve single-mode outcoupling. Furthermore, on account of the sensitive responsiveness of organic materials, reversible wavelength-switching of single-mode laser can be realized through adjusting the resonant modes of the microdisk cavity filter. The results will provide guidance for the rational design of nanophotonic devices with novel performances based on the characteristic of organic materials.

19.
BMC Genomics ; 19(1): 68, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29357812

RESUMO

BACKGROUND: Sweetpotato whitefly, Bemisia tabaci MED/Q and MEAM1/B, are two economically important invasive species that cause considerable damages to agriculture crops through direct feeding and indirect vectoring of plant pathogens. Recently, a draft genome of B. tabaci MED/Q has been assembled. In this study, we focus on the genomic comparison between MED/Q and MEAM1/B, with a special interest in MED/Q's genomic signatures that may contribute to the highly invasive nature of this emerging insect pest. RESULTS: The genomes of both species share similarity in syntenic blocks, but have significant divergence in the gene coding sequence. Expansion of cytochrome P450 monooxygenases and UDP glycosyltransferases in MED/Q and MEAM1/B genome is functionally validated for mediating insecticide resistance in MED/Q using in vivo RNAi. The amino acid biosynthesis pathways in MED/Q genome are partitioned among the host and endosymbiont genomes in a manner distinct from other hemipterans. Evidence of horizontal gene transfer to the host genome may explain their obligate relationship. Putative loss-of-function in the immune deficiency-signaling pathway due to the gene loss is a shared ancestral trait among hemipteran insects. CONCLUSIONS: The expansion of detoxification genes families, such as P450s, may contribute to the development of insecticide resistance traits and a broad host range in MED/Q and MEAM1/B, and facilitate species' invasions into intensively managed cropping systems. Numerical and compositional changes in multiple gene families (gene loss and gene gain) in the MED/Q genome sets a foundation for future hypothesis testing that will advance our understanding of adaptation, viral transmission, symbiosis, and plant-insect-pathogen tritrophic interactions.


Assuntos
Genoma de Inseto , Hemípteros/classificação , Hemípteros/genética , Proteínas de Insetos/genética , Resistência a Inseticidas , Animais , Produtos Agrícolas/parasitologia , Sistema Enzimático do Citocromo P-450/genética , Glucuronosiltransferase/genética , Especificidade de Hospedeiro , Família Multigênica , Filogenia , Simbiose , Transcriptoma
20.
Adv Mater ; 29(30)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28605074

RESUMO

Photonic barcodes with a small footprint have demonstrated a great value for multiplexed high-throughput bioassays and tracking systems. Attempts to develop coding technology tend to focus on the generation of featured barcodes both with high coding capacity and accurate recognition. In this work, a strategy to design photonic barcodes is proposed based on whispering-gallery-mode (WGM) modulations in dye-doped microdisk resonant cavities, where each modulated photoluminescence spectrum constitutes the fingerprint of a corresponding microdisk. The WGM-based barcodes can achieve infinite encoding capacity through tuning the dimensions of the microdisks. These photonic barcodes can be well disguised and decoded based on the light controlled proton release and acidichromism of the organic materials, which are essential to fulfill the functions of anti-counterfeiting, information security, and so on. The results will pave an avenue to new types of flexible WGM-based components for optical data recording and security labels.

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