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1.
Phys Rev Lett ; 123(8): 080401, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491194

RESUMO

We report an experiment to test quantum interference, entanglement, and nonlocality using two dissimilar photon sources, the Sun and a semiconductor quantum dot on the Earth, which are separated by ∼150 million kilometers. By making the otherwise vastly distinct photons indistinguishable in all degrees of freedom, we observe time-resolved two-photon quantum interference with a raw visibility of 0.796(17), well above the 0.5 classical limit, providing unambiguous evidence of the quantum nature of thermal light. Further, using the photons with no common history, we demonstrate postselected two-photon entanglement with a state fidelity of 0.826(24) and a violation of Bell inequality by 2.20(6). The experiment can be further extended to a larger scale using photons from distant stars and open a new route to quantum optics experiments at an astronomical scale.

2.
Math Biosci Eng ; 16(4): 2202-2218, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-31137207

RESUMO

In this paper, we develop a novel subspace-based recovery algorithm for non-blind deconvolution (named SND). With considering visual importance difference between image structures and smoothing areas, we propose subspace data fidelity for protecting image structures and suppressing both noise and artifacts. Meanwhile, with exploiting the difference of subspace priors, we put forward differentiation modelings on different subspace priors for improving deblurring performance. Then we utilize the least square integration method to fuse deblurred estimations and to compensate information loss of subspace deblurrings. In addition, we derive an efficient optimization scheme for addressing the proposed objective function by employing the methods of least square and fast Fourier transform. Final experimental results demonstrate that the proposed method outperforms several classical and state-of-the-art algorithms in both subjective and objective assessments.

3.
Phys Rev Lett ; 122(11): 113602, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30951338

RESUMO

An outstanding goal in quantum optics and scalable photonic quantum technology is to develop a source that each time emits one and only one entangled photon pair with simultaneously high entanglement fidelity, extraction efficiency, and photon indistinguishability. By coherent two-photon excitation of a single InGaAs quantum dot coupled to a circular Bragg grating bull's-eye cavity with a broadband high Purcell factor of up to 11.3, we generate entangled photon pairs with a state fidelity of 0.90(1), pair generation rate of 0.59(1), pair extraction efficiency of 0.62(6), and photon indistinguishability of 0.90(1) simultaneously. Our work will open up many applications in high-efficiency multiphoton experiments and solid-state quantum repeaters.

4.
Adv Mater ; 31(19): e1807865, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30920709

RESUMO

The synthesis of highly crystalline covalent triazine frameworks (CTFs) with ultrastrong covalent bonds (aromatic CN) from the triazine linkage presents a great challenge to synthetic chemists. Herein, the synthesis of highly crystalline CTFs via directly controlling the monomer feeding rate is reported. By tuning the feeding rate of monomers, the crystallization process can be readily governed in a controlled manner in an open system. The sample of CTF-HUST-HC1 with abundant exposed {001} crystal facets has the better crystallinity and thus is selected to study the effect of high crystallinity on photoelectric properties. Owing to the better separation of photogenerated electron-hole pairs and charge transfer, the obtained highly ordered CTF-HUST-HC1 has superior performance in the photocatalytic removal of nitric oxide (NO) than its lesser crystalline counterparts and g-C3 N4 .

5.
Angew Chem Int Ed Engl ; 58(12): 3918-3922, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30694598

RESUMO

A novel strategy for the expedient construction of CF3 -embeded tertiary/quarternary carbon centers was developed by taking advantage of photoredox catalysis. Thanks to a key step of single-electron oxidation, electron-rich gem-difluoroalkenes, which otherwise are essentially reluctant towards F-nucleoplilic addition, now readily participate in this fluoroallylation reaction. Furthermore, this strategy provides an elegant example for the generation, as well as functionalization, of α-CF3 -substituted benzylic radical intermediates using cheap and readily available starting materials.

6.
Phys Rev Lett ; 121(10): 100502, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30240268

RESUMO

Periodically driven systems have displayed a variety of fascinating phenomena without analogies in static systems, which enrich the classification of quantum phases of matter and stimulate a wide range of research interests. Here, we employ discrete-time quantum walks to investigate a nontrivial topological effect unique to a two-dimensional periodically driven system: chiral edge states can exist at the interface of Floquet insulators whose Chern numbers vanish. Thanks to a resource-saving and flexible fiber-loop architecture, we realize inhomogeneous two-dimensional quantum walks up to 25 steps, over an effective 51×51 lattice with tunable local parameters. Spin-polarized chiral edge states are observed at the boundary of two distinct quantum walk domains. Our results contribute to establishing a well-controlled platform for exploring nontrivial topological phases.

7.
Mol Ther Nucleic Acids ; 13: 44-54, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30240970

RESUMO

Non-coding RNAs play an important role in the pathogenesis of pulmonary arterial hypertension (PAH). The aim of this study was to characterize the therapeutic role of melatonin as well as the underlying molecular mechanism (its effects on the expression of H19 and its downstream signaling pathways) in the treatment of PAH. Real-time PCR and western blot analysis were performed to evaluate the expression of H19, miR-200a, miR-675, insulin-like growth factor-1 receptor (IGF1R), and programmed cell death 4 (PDCD4). The value of systolic pulmonary artery pressure (SPAP) and the ratio of medial thickening in the monocrotaline (MCT) group were increased, whereas the melatonin treatment could decrease these values to some extent. The weights of RV (right ventricle), LV (left ventricle) + IVS (interventricular septal), and RV/(LV + IVS) in the MCT group were much higher than those in the MCT + melatonin and control groups. In addition, the expression of H19, miR-675, IGF1R mRNA, and IGF1R protein in the MCT group was the highest, whereas their expression in the control group was the lowest. The expression of miR-200, PDCD4 mRNA, and PDCD4 protein in the MCT group was the lowest, whereas their expression in the control group was the highest. Furthermore, H19 directly suppressed the expression of miR-200a, whereas miR-675-3p and miR-200a directly inhibited the expression of IGF1R and PDCD4, respectively. Finally, melatonin treatment inhibited cell proliferation; upregulated the expression of H19, miR-675-3p, and PDCD4; and downregulated the expression of miR-200a and IGF1R. This study demonstrated the role of H19-miR-675-3p-IGF1R- and H19-miR-200a-PDCD4-signaling pathways in the melatonin treatment of PAH.

8.
Exp Ther Med ; 16(3): 2554-2558, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30186488

RESUMO

Pulmonary actinomycosis is a chronic, suppurative, granulomatous disease caused by Actinomyces israelii, an obligate anaerobe. The clinical manifestations and imaging characteristics of pulmonary actinomycosis lack specificity and can lead to confusion with tuberculosis and lung cancer. The present study reported a case of pulmonary actinomycosis diagnosed by transbronchoscopic lung biopsy and reviewed the literature on the disease. The clinical characteristics, signs, laboratory findings as well as progression, diagnosis and treatment in the case of pulmonary actinomycosis were analyzed. The patient was diagnosed by transbronchoscopic lung biopsy. After two weeks of antibiotic therapy, the cough was significantly improved and the patient's temperature returned to normal. Moreover, the lesion in the left lower lung was significantly smaller. Pulmonary actinomycosis is usually confused for tuberculosis and lung cancer. The present findings indicated that transbronchoscopic lung biopsy is a useful tool for diagnosing the disease. To conclude, doctors should have a clear enough understanding of the disease to prescribe empirical antibiotics and avoid unnecessary surgery.

9.
Sci Rep ; 8(1): 12489, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30131509

RESUMO

Epizootic rabbit enteropathy (ERE) is reproduced successfully in the present study by feeding rabbits a low-fibre diet, and high-throughput sequencing and quantitative real-time PCR (qPCR) analysis were applied to examine the microbial variations in the stomach, small intestine and caecum. The evenness was disturbed and the richness was decreased in the ERE groups. When the rabbits were suffering from ERE, the abundance of the Firmicutes was decreased in three parts of the digestive tract, whereas the Proteobacteria was increased in the stomach and caecum, the Bacteroidetes and Verrucomicrobia were increased in the small intestine. Correlation analysis showed that the reduced concentrations of TVFA and butyrate in the caeca of the ERE group were attributed to the decreased abundances of genera such as Lactobacillus, Alistipes and other fibrolytic bacteria and butyrate- producing bacteria such as Eubacterium and Faecalibacterium. It is concluded that, in terms of microorganisms, the overgrowth of Bacteroides fragilis, Clostridium perfringen, Enterobacter sakazakii and Akkermansia muciniphila and inhibition of Bifidobacterium spp. and Butyrivibrio fibrisolvens in the stomach, small intestine and caecum resulted in a decrease in butyrate yield, leading to the incidence of ERE, and the probability of developing ERE could be manipulated by adjusting the dietary fibre level.

10.
Int J Mol Sci ; 19(6)2018 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-29861481

RESUMO

The UGlcAE has the capability of interconverting UDP-d-galacturonic acid and UDP-d-glucuronic acid, and UDP-d-galacturonic acid is an activated precursor for the synthesis of pectins in plants. In this study, we identified nine UGlcAE protein-encoding genes in tomato. The nine UGlcAE genes that were distributed on eight chromosomes in tomato, and the corresponding proteins contained one or two trans-membrane domains. The phylogenetic analysis showed that SlUGlcAE genes could be divided into seven groups, designated UGlcAE1 to UGlcAE6, of which the UGlcAE2 were classified into two groups. Expression profile analysis revealed that the SlUGlcAE genes display diverse expression patterns in various tomato tissues. Selective pressure analysis indicated that all of the amino acid sites of SlUGlcAE proteins are undergoing purifying selection. Fifteen stress-, hormone-, and development-related elements were identified in the upstream regions (0.5 kb) of these SlUGlcAE genes. Furthermore, we investigated the expression patterns of SlUGlcAE genes in response to three hormones (indole-3-acetic acid (IAA), gibberellin (GA), and salicylic acid (SA)). We detected firmness, pectin contents, and expression levels of UGlcAE family genes during the development of tomato fruit. Here, we systematically summarize the general characteristics of the SlUGlcAE genes in tomato, which could provide a basis for further function studies of tomato UGlcAE genes.


Assuntos
Carboidratos Epimerases/metabolismo , Frutas/metabolismo , Lycopersicon esculentum/enzimologia , Família Multigênica , Sequência de Aminoácidos , Carboidratos Epimerases/química , Carboidratos Epimerases/genética , Carboidratos Epimerases/isolamento & purificação , Frutas/enzimologia , Frutas/genética , Regulação da Expressão Gênica de Plantas , Genômica , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de Sequência de Proteína
11.
Small ; 14(7)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29325210

RESUMO

Design of new nanoagents that intrinsically have both diagnostic imaging and therapeutic capabilities is highly desirable for personalized medicine. In this work, a novel nanotheranostic agent is fabricated based on polydopamine (PDA)-functionalized Co-P nanocomposites (Co-P@PDA) for magnetic resonance imaging (MRI)-guided combined photothermal therapy and chemotherapy. The ultrahigh relaxivity of 224.61 mm-1 s-1 can enable Co-P@PDA to be applied as an excellent contrast agent for MRI in vitro and in vivo, providing essential and comprehensive information for tumor clinical diagnosis. Moreover, Co-P@PDA exhibit excellent photothermal performance owing to the strong near-infrared (NIR) absorbance of both Co-P nanocomposite and PDA. Highly effective ablation of tumors is achieved in a murine tumor model because the NIR laser not only induces photothermal effects but also triggers the chemotherapeutic drug on-demand release, which endows the Co-P@PDA with high curative effects but little toxicity and few side effects. These findings demonstrate that Co-P@PDA are promising agents for highly effective and precise antitumor treatment and warrant exploration as novel theranostic nanoagents with good potential for future clinical translation.

12.
J Cell Biochem ; 119(2): 1942-1952, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28816418

RESUMO

The objective of this study was to explore the role of miRNAs in the control of HPH as well as molecular mechanism underlying. Computational analysis and luciferase assay were carried out to search the target gene of miR-26b. Luciferase assay, RT-PCR and western-blot analysis was performed to test interaction among hypoxia, miR-26b, SRF and CTGF. MiR-26b was significantly downregulated; meanwhile, CTGF and SRF were significantly upregulated in HPH rat model. Using computational analysis, CTGF was found to be a virtual target gene of miR-26b, and only cell transfected with vectors containing wild-type CTGF 3'UTR and miR-26b showed a lower luciferase activity than scramble control. Hypoxia significantly inhibited miR-26b promoter, and promoted SRF promoter. Meanwhile, hypoxia had no effect on CTGF promoter. In addition, SRF promoted the promoter of CTGF. MiR-26b was significantly downregulated; meanwhile, CTGF and SRF were upregulated in PASMCs exposed to hypoxia. In addition, miR-26b and SRF siRNA, but not CTGF siRNA, significantly inhibited SRF expression. Meanwhile, miR-26b, SRF siRNA, and CTGF siRNA significantly inhibited CTGF expression in hypoxia-treated cell. PASMCs treated with hypoxia showed higher cell viability and higher percentage cells in S phase than the control, which could be reversed by miR-26b, SRF siRNA, and CTGF siRNA transfection. These findings suggested that hypoxia induced miR-26b inhibition and SRF and CTGF upregulation in HPH rat model. CTGF mediated hypoxia-induced regulation of miR-26b and SRF in proliferation of PASMCs, which indicated that hypoxia-induced miR-26b inhibition contributed to the pathogenesis of HPH via CTGF.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/genética , Regulação para Baixo , Hipertensão Pulmonar/genética , MicroRNAs/genética , Fatores de Transcrição/genética , Regiões 3' não Traduzidas , Animais , Hipóxia Celular , Células Cultivadas , Modelos Animais de Doenças , Miócitos de Músculo Liso/citologia , Regiões Promotoras Genéticas , Ratos
13.
Phys Rev Lett ; 121(25): 250505, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30608840

RESUMO

Entangled-photon sources with simultaneously near-unity heralding efficiency and indistinguishability are the fundamental elements for scalable photonic quantum technologies. We design and realize a degenerate telecommunication wavelength entangled-photon source from an ultrafast pulsed laser pumped spontaneous parametric down-conversion (SPDC), which shows simultaneously 97% heralding efficiency and 96% indistinguishability between independent single photons without narrow-band filtering. Such a beamlike and frequency-uncorrelated SPDC source allows generation of the first 12-photon genuine entanglement with a state fidelity of 0.572±0.024. We further demonstrate a blueprint of scalable scattershot boson sampling using 12 SPDC sources and a 12×12 mode interferometer for three-, four-, and five-boson sampling, which yields count rates more than 4 orders of magnitude higher than all previous SPDC experiments.

14.
Org Lett ; 19(22): 6164-6167, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29112428

RESUMO

A visible-light-engaged 2-fold site-selective alkylation of indole derivatives with aliphatic ethers or alcohols has been accomplished for easy access to symmetric 3,3'-bisindolylmethane derivatives. The experimental data suggest a sequential photoredox catalysis induced radical addition and proton-mediated Friedel-Crafts alkylation mechanism.

15.
Chem Commun (Camb) ; 53(68): 9482-9485, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28795700

RESUMO

An unprecedented Rh-catalyzed C2-difluoroalkylation of indole derivatives with 2,2-difluorovinyl arenesulfonates has been reported. This reaction provides a rare instance of catalytic difluoroalkylation through hydroarylation of gem-difluoroalkenes. The sulfonate group works as a chelating ligand, thus stabilizing the rhodacycle intermediate, leading to the uncommon transformation.

16.
Fitoterapia ; 121: 206-211, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28778562

RESUMO

Five picrotoxane sesquiterpenoids belonging to the unusual dendrobine-type (1 and 4) and the picrotoxinin-type (2, 3, and 5) were isolated from the stems of Dendrobium nobile Lindl. Their structures were established by spectroscopic analyses and physical properties. Compound 1 was a new dendrobine analogue. Although the planar structure of 2 and 3 had been reported, their absolute configurations were first determined by single-crystal X-ray diffraction and circular dichroism. Compound 2 exhibited angiogenesis effect against sunitinib-induced damage on intersegmental blood vessels in Tg (flk1: EGFP) and Tg (fli1: nEGFP) transgenic zebrafish at concentrations of 3.13, 6.25, 12.50, and 25.00µM.


Assuntos
Alcaloides/farmacologia , Indutores da Angiogênese/farmacologia , Dendrobium/química , Sesquiterpenos/farmacologia , Alcaloides/isolamento & purificação , Indutores da Angiogênese/isolamento & purificação , Animais , Animais Geneticamente Modificados , Estrutura Molecular , Caules de Planta/química , Sesquiterpenos/isolamento & purificação , Peixe-Zebra
17.
Chem Commun (Camb) ; 53(62): 8731-8734, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28726856

RESUMO

The manganese-catalyzed α-fluoroalkenylation of arenes via C-H activation and C-F cleavage has been described. This protocol provides a very useful method for the synthesis of monofluoroalkenes with predominant unconventional E-isomer selectivity which complements the existing strategies for the access to these molecular architectures. In addition, the selectivity of ß-defluorination in the catalytic cycle not only determines the configurations of the products but also obviates the use of external oxidants, providing a good example in the exploitation of manganese-catalyzed redox-neutral C-H transformations.

18.
Adv Mater ; 29(31)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28614603

RESUMO

Solar-driven reduction of dinitrogen (N2 ) to ammonia (NH3 ) is severely hampered by the kinetically complex and energetically challenging multielectron reaction. Oxygen vacancies (OVs) with abundant localized electrons on the surface of bismuth oxybromide-based semiconductors are demonstrated to have the ability to capture and activate N2 , providing an alternative pathway to overcome such limitations. However, bismuth oxybromide materials are susceptible to photocorrosion, and the surface OVs are easily oxidized and therefore lose their activities. For realistic photocatalytic N2 fixation, fabricating and enhancing the stability of sustainable OVs on semiconductors is indispensable. This study shows the first synthesis of self-assembled 5 nm diameter Bi5 O7 Br nanotubes with strong nanotube structure, suitable absorption edge, and many exposed surface sites, which are favorable for furnishing sufficient visible light-induced OVs to realize excellent and stable photoreduction of atmospheric N2 into NH3 in pure water. The NH3 generation rate is as high as 1.38 mmol h-1 g-1 , accompanied by an apparent quantum efficiency over 2.3% at 420 nm. The results presented herein provide new insights into rational design and engineering for the creation of highly active catalysts with light-switchable OVs toward efficient, stable, and sustainable visible light N2 fixation in mild conditions.

19.
J Cell Biochem ; 118(9): 2731-2738, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28176371

RESUMO

The aim of study was to investigate the involvement of hypoxia-induced upregulation of serum response factor (SRF) and its downstream effector, B cell leukemia-2 (Bcl-2), in hypoxia-induced pulmonary hypertension (PH). Immunohistochemistry analysis and western blot analysis were used to detect the levels of SRF and Bcl-2 in rats exposed to hypoxia. Furthermore, the regulatory relationship between SRF and Bcl-2 was investigated in PASMCs using real-time PCR and western-blot analysis. We found that mPAP (mean pulmonary arterial pressure) and WA (the ratio of vascular wall area to external diameter) were increased after exposure to hypoxia, while LA (the ratio of vascular lumen area to total area) decreased after exposure to hypoxia. The immunohistochemistry analysis displayed a substantial increase in SRF and Bcl-2 in pulmonary arterial walls after 14 days of hypoxia. And the western blotting showed that SRF and Bcl-2 protein levels were much higher after 7 days of hypoxia and then remained at a high level. And then the levels of SRF and Bcl-2 in pulmonary artery smooth muscle cells (PASMCs) exposed to hypoxia were substantially suppressed following introduction of SRF siRNA, and the level of Bcl-2 was remarkably inhibited by Bcl-2 siRNA, while Bcl-2 siRNA had no effect on SRF level. Finally, SRF siRNA, and Bcl-2 siRNA significantly reduced viability of PASMCs exposed to hypoxia, and enhanced apoptosis of PASMCs exposed to hypoxia. These data validated that SRF responded to hypoxia, which subsequently was involved in pulmonary hypertension by abnormally promoting viability of PASMCs via modulating expression of Bcl-2. J. Cell. Biochem. 118: 2731-2738, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Hipertensão Pulmonar/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Fatores de Transcrição/biossíntese , Regulação para Cima , Animais , Hipóxia Celular , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/patologia , Ratos , Ratos Wistar
20.
Water Res ; 112: 9-18, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28110246

RESUMO

In this study, an electrochemical/electro-Fenton oxidation (EC/EF) system was designed to degrade atrazine, by utilizing boron-doped diamond (BDD) and Fe@Fe2O3 core-shell nanowires loaded active carbon fiber (Fe@Fe2O3/ACF) as the anode and the cathode, respectively. This EC/EF system exhibited much higher degradation rate, decholorination and mineralization efficiency of atrazine than the electrochemical (EC) and electrochemical/traditional electro-Fenton (EC/TEF) oxidation counterpart systems without Fe@Fe2O3 core-shell nanowires. Active species trapping experiment revealed that Fe@Fe2O3 could activate molecular oxygen to produce more OH through Fenton reaction, which favored the atrazine degradation. High performance liquid chromatography, high performance liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry were applied to probe the decomposition and mineralization of atrazine during this novel EC/EF process, which revealed that two intermediates of triazinons (the isomerization of hydroxylated atrazine) were generated during the electrochemical/electro-Fenton oxidation of atrazine in the presence of Fe@Fe2O3 core-shell nanowires. The experimental and theoretical calculation results suggested that atrazine might be degraded via a triazinon ring opening mechanism, while the presence of Fe@Fe2O3 notably accelerated the decholorination process, and produced more hydroxylated products to promote the generation of trazinons and the subsequent ring cleavage as well as the final complete mineralization. This work provides a deep insight into the triazine ring opening mechanism and the design of efficient electrochemical advanced oxidation technologies (EAOTs) for persistent organic pollutant removal.


Assuntos
Atrazina/química , Compostos Férricos/química , Boro/química , Diamante/química , Eletrodos , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução , Poluentes Químicos da Água/química
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