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1.
Phys Rev E ; 109(5-1): 054132, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907473

RESUMO

One of the main challenges in developing high-performance quantum batteries is the self-discharging process, where energy is dissipated from a quantum battery into the environment. In this work, we investigate the influence of non-Markovian noises on the performance of a quantum battery. Our results demonstrate that adding auxiliary qubits to a quantum battery system can effectively suppress the self-discharging process, leading to an improvement in both the steady-state energy and extractable work. We reveal that the physical mechanism inhibiting the self-discharging process is the formation of system-environment bound states, rather than an increase in non-Markovianity. Our results could be of both theoretical and experimental interest in exploring the ability of quantum batteries to maintain long stored energy in the environment.

2.
Sci Adv ; 5(7): eaav9445, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360764

RESUMO

The hybrid nature and soft lattice of organolead halide perovskites render their structural changes and optical properties susceptible to external driving forces such as temperature and pressure, remarkably different from conventional semiconductors. Here, we investigate the pressure-induced optical response of a typical two-dimensional perovskite crystal, phenylethylamine lead iodide. At a moderate pressure within 3.5 GPa, its photoluminescence red-shifts continuously, exhibiting an ultrabroad energy tunability range up to 320 meV in the visible spectrum, with quantum yield remaining nearly constant. First-principles calculations suggest that an out-of-plane quasi-uniaxial compression occurs under a hydrostatic pressure, while the energy is absorbed by the reversible and elastic tilting of the benzene rings within the long-chain ligands. This anisotropic structural deformation effectively modulates the quantum confinement effect by 250 meV via barrier height lowering. The broad tunability within a relatively low pressure range will expand optoelectronic applications to a new paradigm with pressure as a tuning knob.

3.
J Colloid Interface Sci ; 554: 572-579, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326789

RESUMO

Immobilization of polyoxometalates (POMs) plays significant roles in their industrial applications. In this work, POM-supported catalyst has been developed with cellulose nanocrystal (CNC) as a sustainable carrier and employed in the aerobic oxidative desulfurization (AODS) of fuels. The catalyst was constructed by grafting a poly(ionic liquid) (PIL) onto CNCs and subsequently exchanging the counterions of the PIL into [Co(OH)6Mo6O18]3-, a kind of POM anionic clusters. The resulting CNC@PIL@POM was systematically characterized and utilized as a catalyst in the AODS of thiophenic compounds including benzothiophene (BT), dibenzothiophene (DBT), and 4, 6-dimethyldibenzothiophene (4, 6-DMDBT), with oxygen contained in air as oxidizing agent. The catalyst could achieve complete conversion of DBT in model diesel under mild condition and be reused five times without apparent losing of activity. As for the desulfurization of a real diesel, it was demonstrated that almost all of the original sulfides were completely converted. Based on these results, it is expected that the core-shell POM-supported catalyst may serve as an efficient, separable and sustainable catalyst for AODS of fuels.

4.
Mol Plant ; 11(3): 429-442, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29229569

RESUMO

Eucommia ulmoides, also called hardy rubber tree, is an economically important tree; however, the lack of its genome sequence restricts the fundamental biological research and applied studies of this plant species. Here, we present a high-quality assembly of its ∼1.2-Gb genome (scaffold N50 = 1.88 Mb) with at least 26 723 predicted genes for E. ulmoides, the first sequenced genome of the order Garryales, which was obtained using an integrated strategy combining Illumina sequencing, PacBio sequencing, and BioNano mapping. As a sister taxon to lamiids and campanulids, E. ulmoides underwent an ancient genome triplication shared by core eudicots but no further whole-genome duplication in the last ∼125 million years. E. ulmoides exhibits high expression levels and/or gene number expansion for multiple genes involved in stress responses and the biosynthesis of secondary metabolites, which may account for its considerable environmental adaptability. In contrast to the rubber tree (Hevea brasiliensis), which produces cis-polyisoprene, E. ulmoides has evolved to synthesize long-chain trans-polyisoprene via farnesyl diphosphate synthases (FPSs). Moreover, FPS and rubber elongation factor/small rubber particle protein gene families were expanded independently from the H. brasiliensis lineage. These results provide new insights into the biology of E. ulmoides and the origin of polyisoprene biosynthesis.


Assuntos
Genoma de Planta/genética , Hemiterpenos/metabolismo , Hevea/genética , Hevea/metabolismo , Filogenia , Proteínas de Plantas/genética
5.
Sci Rep ; 7(1): 17372, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234118

RESUMO

In classical optics, Young's double-slit experiment with colored coherent light gives rise to individual interference fringes for each light frequency, referring to single-photon interference. However, two-photon double-slit interference has been widely studied only for wavelength-degenerate biphoton, known as subwavelength quantum lithography. In this work, we report double-slit interference experiments with two-color biphoton. Different from the degenerate case, the experimental results depend on the measurement methods. From a two-axis coincidence measurement pattern we can extract complete interference information about two colors. The conceptual model provides an intuitional picture of the in-phase and out-of-phase photon correlations and a complete quantum understanding about the which-path information of two colored photons.

6.
J Mater Chem B ; 5(34): 7035-7050, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263895

RESUMO

A silk scaffold exhibits high potential for the human anterior cruciate ligament (ACL) reconstruction due to its exceptional mechanics as well as biocompatibility. Inefficient ACL interface restoration is thought to be a major hurdle for the common implementation of a silk-based ligament graft. By integrating a stratified approach and gene immobilization, here we developed a gene-immobilized triphasic silk scaffold to enhance ACL osseointegration. Isotropic silk was divided into three regions (respectively corresponding to a ligament, fibrocartilage and the bone region of the native ACL interface) using a custom-made divider, and the lentiviral vector-encoded transforming growth factor beta-3 (TGF-ß3) and bone morphogenetic protein-2 (BMP2) was further, respectively, immobilized to phosphatidylserine (PS)-coated fibrocartilage and the bone region of the triphasic silk scaffold. The in vitro assessments displayed that this gene-immobilized triphasic silk scaffold significantly promotes bone marrow mesenchymal stem cell (BMSC) proliferation and differentiation into corresponding cell lineage. Moreover, the gene-modified triphasic silk scaffold combined with BMSCs alone, which was rolled into a compact shaft to be implanted onto rabbit ACL-defect models, revealed roughly complete osseointegration restoration as a result of apparent three-layered tissue formation and robust mechanical ability as early as 12 weeks postoperatively. These outcomes demonstrated that employing the stratified approach and gene immobilization efficiently expedites silk-mediated ACL interface formation, expanding the therapeutic potential of the silk-based ligament graft for ACL reconstruction.

7.
Stem Cells Int ; 2016: 9842075, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27525012

RESUMO

Mesenchymal stem cells (MSCs) and fibroblasts are two major seed cells for ligament tissue engineering. To understand the effects of mechanical stimulation on these cells and to develop effective approaches for cell therapy, it is necessary to investigate the biological effects of various mechanical loading conditions on cells. In this study, fibroblasts and MSCs were tested and compared under a novel Uniflex/Bioflex culture system that might mimic mechanical strain in ligament tissue. The cells were uniaxially or radially stretched with different strains (5%, 10%, and 15%) at 0.1, 0.5, and 1.0 Hz. The cell proliferation and collagen production were compared to find the optimal parameters. The results indicated that uniaxial stretch (15% at 0.5 Hz; 10% at 1.0 Hz) showed positive effects on fibroblast. The uniaxial strains (5%, 10%, and 15%) at 0.5 Hz and 10% strain at 1.0 Hz were favorable for MSCs. Radial strain did not have significant effect on fibroblast. On the contrary, the radial strains (5%, 10%, and 15%) at 0.1 Hz had positive effects on MSCs. This study suggested that fibroblasts and MSCs had their own appropriate mechanical stimulatory parameters. These specific parameters potentially provide fundamental knowledge for future cell-based ligament regeneration.

8.
Biomaterials ; 106: 180-92, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27566867

RESUMO

The biodegradable silk-based scaffold with unique mechanical property and biocompatibility represents a favorable ligamentous graft for tissue-engineering anterior cruciate ligament (ACL) reconstruction. However, the low efficiency of ligament-bone interface restoration barriers the isotropic silk graft to common ACL therapeutics. To enhance the regeneration of the silk-mediated interface, we developed a specialized stratification approach implementing a sequential modification on isotropic silk to constitute a triphasic silk-based graft in which three regions respectively referring to ligament, cartilage and bone layers of interface were divided, followed by respective biomaterial coating. Furthermore, three types of cells including bone marrow mesenchymal stem cells (BMSCs), chondrocytes and osteoblasts were respectively seeded on the ligament, cartilage and bone region of the triphasic silk graft, and the cell/scaffold complex was rolled up as a multilayered graft mimicking the stratified structure of native ligament-bone interface. In vitro, the trilineage cells loaded on the triphasic silk scaffold revealed a high proliferative capacity as well as enhanced differentiation ability into their corresponding cell lineage. 24 weeks postoperatively after the construct was implanted to repair the ACL defect in rabbit model, the silk-based ligamentous graft exhibited the enhancement of osseointegration detected by a robust pullout force and formation of three-layered structure along with conspicuously corresponding matrix deposition via micro-CT and histological analysis. These findings potentially broaden the application of silk-based ligamentous graft for ACL reconstruction and further large animal study.


Assuntos
Lesões do Ligamento Cruzado Anterior/patologia , Lesões do Ligamento Cruzado Anterior/terapia , Regeneração Tecidual Guiada/instrumentação , Ligamentos/crescimento & desenvolvimento , Regeneração/fisiologia , Seda/química , Transplantes/crescimento & desenvolvimento , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Desenvolvimento Ósseo , Osso e Ossos/citologia , Células Cultivadas , Condrócitos/citologia , Condrócitos/transplante , Regeneração Tecidual Guiada/métodos , Ligamentos/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Osteoblastos/transplante , Transição de Fase , Alicerces Teciduais , Transplantes/citologia , Resultado do Tratamento
9.
Biomed Res Int ; 2014: 637821, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25093176

RESUMO

Hydroxyapatite (HA) can be coated on various materials surface and has the function of osteogenicity. Microporous silk scaffold has excellent biocompatibility. In this study, alternate soaking technology was used to coat HA on microporous silk scaffolds. However, the cell proliferation was found to decrease with the increasing thickness (cycles of soaking) of HA-coating. This study aims to determine the best thickness (cycles of soaking) of HA-coating on microporous silk scaffolds. The SEM observation showed that group with one cycle of alternate soaking (1C-HA) has the most optimal porosity like non-HA-modified microporous silk scaffolds. The proliferation of osteoblasts has no significant difference between noncoated HA (N-HA) and 1C-HA groups, which are both significantly higher than those in two cycles of soaking (2C-HA) and three cycles of soaking (3C-HA) groups. The transcription levels of specific genes (runx2 and osteonectin) in osteoblasts of 1C-HA group were significantly higher than those of N-HA group. Moreover, the levels showed no significant difference among 1C-HA, 2C-HA, and 3C-HA groups. In conclusion, microporous silk scaffold with 1 cycle of HA-coating can combine the biocompatibility of silk and osteogenicity of HA.


Assuntos
Proliferação de Células/efeitos dos fármacos , Durapatita/química , Osteoblastos/efeitos dos fármacos , Engenharia Tecidual , Animais , Materiais Revestidos Biocompatíveis/química , Durapatita/farmacologia , Humanos , Porosidade , Coelhos , Seda/química , Alicerces Teciduais/química
10.
Biomed Res Int ; 2014: 816979, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25019087

RESUMO

The lack of a fibrocartilage layer between graft and bone remains the leading cause of graft failure after anterior cruciate ligament (ACL) reconstruction. The objective of this study was to develop a gene-modified silk cable-reinforced chondroitin sulfate-hyaluronate acid-silk fibroin (CHS) hybrid scaffold for reconstructing the fibrocartilage layer. The scaffold was fabricated by lyophilizing the CHS mixture with braided silk cables. The scanning electronic microscopy (SEM) showed that microporous CHS sponges were formed around silk cables. Each end of scaffold was modified with lentiviral-mediated transforming growth factor- ß 3 (TGF- ß 3) gene. The cells on scaffold were transfected by bonded lentivirus. In vitro culture demonstrated that mesenchymal stem cells (MSCs) on scaffolds proliferated vigorously and produced abundant collagen. The transcription levels of cartilage-specific genes also increased with culture time. After 2 weeks, the MSCs were distributed uniformly throughout scaffold. Deposited collagen was also found to increase. The chondral differentiation of MSCs was verified by expressions of collagen II and TGF- ß 3 genes in mRNA and protein level. Histology also confirmed the production of cartilage extracellular matrix (ECM) components. The results demonstrated that gene-modified silk cable-reinforced CHS scaffold was capable of supporting cell proliferation and differentiation to reconstruct the cartilage layer of interface.


Assuntos
Lentivirus/genética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Fator de Crescimento Transformador beta3/genética , Adsorção , Animais , Materiais Biocompatíveis/síntese química , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Adesão Celular/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Sulfatos de Condroitina/química , Fibroínas/química , Vetores Genéticos/genética , Ácido Hialurônico/química , Ligamentos/citologia , Ligamentos/fisiologia , Teste de Materiais , Coelhos , Engenharia Tecidual/métodos
11.
Zhongguo Zhen Jiu ; 25(1): 7-10, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16309145

RESUMO

OBJECTIVE: To assess the therapeutic effect of acupuncture on insomnia. METHODS: A systematic evaluation of all relevant randomized controlled trials (RCT) about acupuncture and moxibustion treatment of insomnia was carried out. The data were statistically analyzed with a special software RevMan 4.1. RESULTS: Six papers of RCT including 585 patients met the enrolled criteria. All of the trials were of lower in methodological quality without using blind method; Meta-analysis indicated that odds ratio was 3.55, 95% confidence interval [2.50, 5.05], P < 0.0001, as acupuncture group compared with drug group. CONCLUSION: Acupuncture is possibly effective for insomnia. However, because of lower methodological quality of all the trials, this conclusion has no enough evidence.


Assuntos
Moxibustão , Distúrbios do Início e da Manutenção do Sono , Acupuntura , Terapia por Acupuntura , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Phys Rev Lett ; 94(17): 173601, 2005 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15904288

RESUMO

We report the experimental observation of classical subwavelength double slit interference with a pseudothermal light source. The experimental results are in good agreement with the theoretical simulation using the second order correlation function for the thermal light.

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