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1.
Cogn Neurodyn ; 18(4): 2003-2013, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39104674

RESUMO

The role of network metrics in exploring brain networks of mental illness is crucial. This study focuses on quantifying a node controllability index (CA-scores) and developing a novel framework for studying the dysfunction of attention deficit hyperactivity disorder (ADHD) brains. By analyzing fMRI data from 143 healthy controls and 102 ADHD patients, the controllability metric reveals distinct differences in nodes (brain regions) and subsystems (functional modules). There are significantly atypical CA-scores in the Rolandic operculum, superior medial orbitofrontal cortex, insula, posterior cingulate gyrus, supramarginal gyrus, angular gyrus, precuneus, heschl gyrus, and superior temporal gyrus of ADHD patients. A comparison with measures of connection strength, eigenvector centrality, and topology entropy suggests that the controllability index may be more effective in identifying abnormal regions in ADHD brains. Furthermore, our controllability index could be extended to investigate functional networks associated with other psychiatric disorders. Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-023-10063-z.

2.
Angew Chem Int Ed Engl ; 63(12): e202318355, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38265930

RESUMO

Cost-effective, non-fluorinated polymer proton exchange membranes (PEMs) are highly desirable in emerging hydrogen fuel cells (FCs) technology; however, their low proton conductivities and poor chemical and dimension stabilities hinder their further development as alternatives to commercial Nafion®. Here, we report the inorganic-organic hybridization strategy by facilely complexing commercial polymers, polyvinyl butyral (PVB), with inorganic molecular nanoparticles, H3 PW12 O40 (PW) via supramolecular interaction. The strong affinity among them endows the obtained nanocomposites amphiphilicity and further lead to phase separation for bi-continuous structures with both inter-connected proton transportation channels and robust polymer scaffold, enabling high proton conductivities, mechanical/dimension stability and barrier performance, and the H2 /O2 FCs equipped with the composite PEM show promising power densities and long-term stability. Interestingly, the hybrid PEM can be fabricated continuously in large scale at challenging ~10 µm thickness via typical tape casting technique originated from their facile complexing strategy and the hybrids' excellent mechanical properties. This work not only provides potential material systems for commercial PEMs, but also raises interest for the research on hybrid composites for PEMs.

3.
J Phys Chem Lett ; 14(26): 5966-5974, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37345920

RESUMO

With the manipulation of surface charges and loadings, 1 nm super-acidic metal oxide clusters can co-crystallize with poly(ethylene glycol) (PEG) at molecular scale for thermoplastic anhydrous proton exchange membranes (PEMs). The coexistence of crystalline and amorphous regions endows the PEMs with a high Young's modulus and high flexibility, while the noncovalent complex interactions enable facile preparation and (re)processing. Furthermore, the diffusive dynamics of PEG chains is slowed by the confinement effect, while the local segmental dynamics is accelerated due to the transition of the chain conformation from helix to zigzag when confined in the crystalline framework. This greatly facilitates proton transportation in the crystalline region for an excellent anhydrous proton conductivity of 4.5 × 10-3 S cm-1 at 90 °C. The balanced proton conductivity, mechanical strength, and processability of the PEMs contribute to the promising power density of H2/O2 fuel cells assembled with co-crystalline PEMs at high temperatures under dry conditions.

4.
J Microencapsul ; 40(6): 442-455, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37191893

RESUMO

OBJECTIVE: Encapsulation of esculetin into DSPE-MPEG2000 carrier was performed to improve its water solubility and oral bioavailability, as well as enhance its anti-inflammatory effect on a mouse model of ulcerative colitis that was induced with dextran sulphate sodium (DSS). METHODS: We determined the in-vitro and in-vivo high-performance liquid chromatographic (HPLC) analysis method of esculetin; Esculetin-loaded nanostructure lipid carrier (Esc-NLC) was prepared using a thin-film dispersion method, wherein a particle size analyser was used to measure the particle size (PS) and zeta potential (ZP) of the Esc-NLC, while a transmission electron microscope (TEM) was employed to observe its morphology. Also, HPLC was used to measure its drug loading (DL), encapsulation efficiency (EE) and the in-vitro release of the preparation, as well as investigate the pharmacokinetic parameters. In addition, its anti-colitis effect was evaluated via histopathological examination of HE-stained sections and detection of the concentrations of tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (ß), and IL-6 in serum with ELISA kits. RESULTS: The PS of Esc-NLC was 102.29 ± 0.63 nm with relative standard deviation (RSD) of 1.08% (with poly-dispersity index-PDI of 0.197 ± 0.023), while the ZP was -15.67 ± 1.39 mV with RSD of 1.24%. Solubility of esculetin was improved coupled with prolonged release time. Its pharmacokinetic parameters were compared with that of free esculetin, wherein the maximum concentration of the drug in plasma was increased by 5.5 times. Of note, bioavailability of the drug was increased by 1.7 times, while the half-life was prolonged by 2.4 times. In the anti-colitis efficacy experiment, the mice in Esc and Esc-NLC groups exhibited significantly reduced levels of TNF-α, IL-1ß, and IL-6 in their sera comparable to the DSS group. Colon histopathological examination revealed that mice with ulcerative colitis in both Esc and Esc-NLC groups displayed improved inflammation, amid the Esc-NLC groups having the best prophylactic treatment effect. CONCLUSION: Esc-NLC could ameliorate DSS-induced ulcerative colitis by improving bioavailability, prolonging drug release time and regulating cytokine release. This observation confirmed the potential of Esc-NLC to reduce inflammation in ulcerative colitis, albeit the need for follow-up research to verify the application of this strategy to clinical treatment of ulcerative colitis.


Assuntos
Colite Ulcerativa , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Interleucina-6 , Fator de Necrose Tumoral alfa , Inflamação , Excipientes , Lipídeos
5.
Int Urol Nephrol ; 55(4): 1045-1057, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36306049

RESUMO

BACKGROUND: Podocyte injuries and dysfunctions contribute to the development of diabetic nephropathy (DN). This study aimed to investigate the role and novel mechanism of lncRNA 1500026H17Rik in high glucose (HG)-treated podocytes. METHODS: DN mice were induced by streptozotocin, and DN in vitro models were constructed in mouse podocytes treated with HG. The expression of fibrosis-related proteins and early growth response protein 1 (EGR1) was detected by western blot. The expression of 1500026H17Rik, miR-205-5p and EGR1 mRNA was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell apoptosis was monitored by flow cytometry assay. Oxidative stress was assessed according to the levels of superoxide dismutase (SOD), malondialdehyde (MDA) and reactive oxygen species (ROS). Inflammatory response was assessed according to the releases of interleukin-6 (IL-6), interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α). The target relationship between miR-205-5p and 1500026H17Rik or EGR1 was validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay. RESULTS: 1500026H17Rik was upregulated in DN mice and HG-induced podocytes. 1500026H17Rik knockdown alleviated podocyte apoptosis, fibrosis, oxidative stress and inflammation induced by HG. MiR-205-5p was a target of 1500026H17Rik, and EGR1 was a downstream target of miR-205-5p. Rescue experiments presented that miR-205-5p inhibition reversed the effects of 1500026H17Rik knockdown. Moreover, miR-205-5p restoration also ameliorated HG-induced cell injuries, which were overturned by EGR1 overexpression. In addition, EGR1 overexpression recovered podocyte apoptosis, fibrosis, oxidative stress and inflammation weakened by 1500026H17Rik knockdown. CONCLUSION: 1500026H17Rik knockdown alleviated HG-induced podocyte injuries, including apoptosis, fibrosis, oxidative stress and inflammation, by governing the miR-205-5p/EGR1 pathway, thus involving in DN development.


Assuntos
Nefropatias Diabéticas , MicroRNAs , Podócitos , RNA Longo não Codificante , Animais , Camundongos , Podócitos/metabolismo , RNA Longo não Codificante/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , Nefropatias Diabéticas/metabolismo , Apoptose , Inflamação/metabolismo , Glucose/farmacologia , Glucose/metabolismo , Fibrose
6.
Adv Sci (Weinh) ; 9(27): e2201679, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35882629

RESUMO

Hydrogel electrolyte is widely used in solid energy storage devices because of its high ionic conductivity, environmental friendliness, and non-leakage property. However, hydrogel electrolyte is not resistant to freezing. Here, a high proton conductive zwitterionic hydrogel electrolyte with super conductivity of 1.51 mS cm-1 at -50 °C is fabricated by random copolymerization of acrylamide and zwitterionic monomer in the presence of 1 m H2 SO4 and ethylene glycol (EG). The antifreezing performance and low temperature conductivity are ascribed to hydrogen bonds and ionic bonds between the components and water molecules in the system and can be tuned by changing the monomer ratio and EG contents. The proton hopping migration on the ionic group of the polymer chains and Grotthuss proton transport mechanism are responsible for the high proton conductivity while Grotthuss transport is dominated at the glassy state of the polymer chains. The electrolyte-assembled supercapacitor (SC) offers high specific capacitance of 93.5 F g-1 at 25 °C and 62.0 F g-1 at -50 °C with a capacitance retention of 91.1% and 81.5% after 10 000 cycles, respectively. The SC can even work at -70 °C. The electrolyte outperforms most reported antifreezing hydrogel electrolytes and has high potential in low-temperature devices.

7.
J Theor Biol ; 527: 110813, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34144050

RESUMO

In this work, we study the behavior of a time-delayed mutually repressive auto-activating three-gene system. Delays are introduced to account for the location difference between DNA transcription that leads to production of messenger RNA and its translation that result in protein synthesis. We study the dynamics of the system using numerical simulations, computational bifurcation analysis and mathematical analysis. We find Hopf bifurcations leading to stable and unstable rotation in the system, and we study the rotational behavior as a function of cyclic mutual repression parameter asymmetry between each gene pair in the network. We focus on how rotation co-exists with a stable heteroclinic flow linking the three saddles in the system. We find that this coexistence allows for a transition between two markedly different types of rotation leading to strikingly different phenotypes. One type of rotation belongs to Hopf-induced rotation while the other type, belongs to heteroclinic cycling between three saddle nodes in the system. We discuss the evolutionary and biological implications of our findings.


Assuntos
Redes Reguladoras de Genes
8.
ChemSusChem ; 14(9): 2056-2066, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33751843

RESUMO

Traditional liquid electrolytes are volatile, flammable, and easy to leak, which makes the energy storage device easy to burn and explode in the case of overcharge and short circuit. Here, by utilizing the active P-H bond of a flame retardant (DOPO) to graft onto the polymer chain, flame-retardant organic gel electrolytes were fabricated to address these issues. The gel electrolyte had good ionic conductivity of 4 mS cm-1 at 20 °C and good flame retardant ability. By changing the molar ratio of the monomers and the salt concentrations, the mechanical strength of the gel electrolyte could be adjusted (maximum stress≈28 KPa, maximum strain≈305 %). The transport mechanism of lithium ions in the gel polymer electrolyte was proposed. The gel electrolyte-assembled supercapacitor (SC) possessed better electrochemical properties than that of SC assembled by liquid electrolyte. Importantly, the gel-based SC remained basically unchanged under multiple bending cycles. Additionally, the gel electrolyte had good low-temperature tolerance (0.1 mS cm-1 at -40 °C). The gel electrolyte-assembled SC could work normally in the temperature range of -20 to 60 °C. The multiple advantages of gel electrolyte expand the applications in ionic conductor and energy storage devices.

9.
Chaos ; 30(12): 123131, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33380064

RESUMO

In the present study, two types of consensus algorithms, including the leaderless coherence and the leader-follower coherence quantified by the Laplacian spectrum, are applied to noisy windmill graphs. Based on the graph construction, exact solutions are obtained for the leader-follower coherence with freely assigned leaders. In order to compare consensus dynamics of two nonisomorphic graphs with the same number of nodes and edges, two generalized windmill graphs are selected as the network models and then explicit expressions of the network coherence are obtained. Then, coherences of models are compared. The obtained results reveal distinct coherence behaviors originating from intrinsic structures of models. Finally, the robustness of the coherence is analyzed. Accordingly, it is found that graph parameters and the number of leaders have a profound impact on the studied consensus algorithms.

10.
J Nanosci Nanotechnol ; 17(1): 354-362, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29620835

RESUMO

The surface modification of the TiO2 photoelectrode film is one of the promising ways to improve the photovoltaic performance of dye-sensitized solar cell (DSSC). In this work for the acid treatment of TiO2 powder, fluorine containing compounds such as trifluoroacetic acid was carried out to enhance the properties of photoanode. In order to investigate the effect of trifluoroacetyl group, the TiO2 nanopowders were also treated with different acids such as acetic acid, nitric acid, hydrochloric acid, and sulfuric acid and their properties were compared. The TiO2 powders treated with both acetic acid and TFA have possessed smooth surface morphologies as well as enhanced particle dispersions with reduced particle sizes. Photoelectrodes prepared for these two kinds of TiO2 powders accommodated high amounts of dye loading and exhibited excellent light transmittance (wavelength region of 400­600 nm). Electrochemical impedance spectroscopy analysis showed the smallest radius of the semicircle which indicates the enhanced rate of electron transport for the cell based photoelectrode with trifluoroacetic acid treated TiO2 powder. The solar cell from the untreated TiO2 film showed the power conversion efficiency of 8.86% and the highest efficiency of 9.51% was achieved by the cell fabricated from trifluoroacetic acid treated TiO2 film.

11.
Org Lett ; 18(14): 3386-9, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27384258

RESUMO

Novel organic pyridinium ylide sensitizers (NO109-111) consisting of various anchoring groups were synthesized and characterized for applications in dye sensitized solar cells. Compared with the pyridine-N-oxide dye (NO108), the ylide sensitizers with strong electron-withdrawing acceptors exhibited dominant ultraviolet absorption properties and efficient binding abilities to the TiO2 surface. Among these dyes, the pyridinium ylide NO111 sensitized solar cell showed the highest efficiency (5.15%), which was improved to 7.41% by employing coadsorbent chenodeoxycholic acid.

12.
Sci Rep ; 6: 26731, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27253909

RESUMO

The mausoleum complex of the First Emperor of China, Qin Shi Huang (259-210 BC), is one of the most famous and important archaeological sites in China, yet questions remain as to how it was constructed and by whom. Here we present isotopic results of individuals from the Liyi (n = 146) and Shanren sites (n = 14), both associated with the mausoleum complex. Those buried at Liyi represent the local workers/inhabitants of the Qin population, and the δ(13)C (-8.7 ± 1.5%) and δ(15)N (10.3 ± 0.7%) values indicate that they consumed predominately millet and/or domestic animals fed millet. In contrast, the Shanren individuals were prisoners forced to construct the mausoleum (found buried haphazardly in a mass grave and some in iron leg shackles), and their δ(13)C (-15.4 ± 2.9%) and δ(15)N (8.0 ± 0.6%) results indicate a more mixed C3/C4 diet, with possibly less domestic animals and more wild game protein consumed. This pattern of decreased millet consumption is also characteristic of archaeological sites from southern China, and possible evidence the Shanren prisoners originated from this region (possibly the ancient Chu state located in modern day Hubei Province and parts of Hunan and Anhui Provinces). Further, this finding is in agreement with historical sources and is supported by previous ancient DNA evidence that the mausoleum workers had diverse origins, with many genetically related to southern Chinese groups.


Assuntos
Arqueologia , Dieta/história , Prisioneiros/história , China , Feminino , História Antiga , Humanos , Masculino
13.
Artigo em Inglês | MEDLINE | ID: mdl-26274112

RESUMO

We consider practical synchronization on complex dynamical networks under linear feedback control designed by optimal control theory. The control goal is to minimize global synchronization error and control strength over a given finite time interval, and synchronization error at terminal time. By utilizing the Pontryagin's minimum principle, and based on a general complex dynamical network, we obtain an optimal system to achieve the control goal. The result is verified by performing some numerical simulations on Star networks, Watts-Strogatz networks, and Barabási-Albert networks. Moreover, by combining optimal control and traditional pinning control, we propose an optimal pinning control strategy which depends on the network's topological structure. Obtained results show that optimal pinning control is very effective for synchronization control in real applications.

14.
Chaos ; 24(4): 043112, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25554032

RESUMO

In this paper, we study consensus problems in a family of tree networks and investigate first and second order consensus denoted as network coherence characterized by Laplacian spectrum. According to the tree structures, we obtain the recursive relationships of Laplacian matrix and its Laplacian eigenvalues at two successive generations. We then obtain the analytical expressions for the sum of the reciprocals and the square reciprocals of all nonzero Laplacian eigenvalues. Finally, we calculate first and second order network coherence and see that the scalings of first and second order coherence with network size N are lnN and N, which are smaller than some studied tree graphs, such as Peano basin fractal, T-graph, and generalized Vicsek fractal.

15.
Chaos ; 23(3): 033141, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24089977

RESUMO

In a generic model of excitable media, we simulate wave emission from a heterogeneity (WEH) induced by an electric field. Based on the WEH effect, a rotating electric field is proposed to terminate existed spatiotemporal turbulence. Compared with the effects resulted by a periodic pulsed electric field, the rotating electric field displays several improvements, such as lower required intensity, emitting waves on smaller obstacles, and shorter suppression time. Furthermore, due to rotation of the electric field, it can automatically source waves from the boundary of an obstacle with small curvature.


Assuntos
Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/métodos , Estimulação Elétrica , Algoritmos , Animais , Arritmias Cardíacas/fisiopatologia , Biofísica/métodos , Campos Eletromagnéticos , Humanos , Modelos Cardiovasculares , Fatores de Tempo
16.
Cogn Neurodyn ; 4(3): 225-31, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21886675

RESUMO

This paper studies two kinds of synchronization between two discrete-time networks with time delays, including inner synchronization within each network and outer synchronization between two networks. Based on Lyapunov stability theory and linear matrix inequality (LMI), sufficient conditions for two discrete-time networks to be asymptotic stability are derived in terms of LMI. Finally numerical examples are given to illustrate the effectiveness of our derived results. The theoretical understanding provides insights into the dynamics of two or more neural networks with appropriate couplings.

17.
Chaos ; 19(1): 013106, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19334970

RESUMO

In this paper, synchronization between two discrete-time networks, called "outer synchronization" for brevity, is theoretically and numerically studied. First, a sufficient criterion for this outer synchronization between two coupled discrete-time networks which have the same connection topologies is derived analytically. Numerical examples are also given and they are in line with the theoretical analysis. Additionally, numerical investigations of two coupled networks which have different connection topologies are analyzed as well. The involved numerical results show that these coupled networks with different connection matrices can reach synchronization.


Assuntos
Simulação por Computador , Transmissão de Doença Infecciosa , Síndrome da Imunodeficiência Adquirida/epidemiologia , Algoritmos , Animais , Aves , Humanos , Influenza Aviária/epidemiologia , Modelos Neurológicos , Modelos Teóricos , Redes Neurais de Computação , Dinâmica não Linear , Zoonoses
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(4 Pt 2): 046204, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17995079

RESUMO

We study synchronization for two unidirectionally coupled networks. This is a substantial generalization of several recent papers investigating synchronization inside a network. We derive analytically a criterion for the synchronization of two networks which have the same (inside) topological connectivity. Then numerical examples are given which fit the theoretical analysis. In addition, numerical calculations for two networks with different topological connections are presented and interesting synchronization and desynchronization alternately appear with increasing value of the coupling strength.

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