We investigate the molecular origin of mechanical reinforcement in a polymer nanocomposite (PNC) under a glass state via molecular dynamics simulations. The strength of the PNC system is found to be ...reinforced mainly via reduced plastic deformations of the nanoparticle neighborhood (NN). Such a reinforcement effect is found to decay with an increase in the strain rate. The Arrhenius–Eyring relation is used to analyze its origin. The amplitude of the reinforcement is found to be determined by the difference between the energy barrier (ΔE) for the activation of NN and the work (W) done by the applied stress to conquer that barrier. A larger strain rate is found to result in a larger W and, hence, a weaker reinforcement effect. Such a strain-rate dependence is verified in the experimental tensile tests of a poly(vinyl alcohol)/SiO2 composite system. These results not only provide a new understanding of the molecular origin of the reinforcement effect in the PNC system, but also pave the way for a better design of the PNC material properties.
Modifications of activated carbon materials (ACs) towards an increase in the electronic and ionic conductivities are expected to improve their capacitance in the absence of a conductive agent. Char ...derived from cotton straw feed were heat-treated at 800 °C in the presence of TiO2. Simultaneously KOH and K2CO3 were used as activation agents. That process resulted in the formation of perovskite CaTiO3 with an involvement of calcium present in carbon as an impurity. The composite were extensively characterized from the point of view of a texture, surface chemistry and electrochemical performance. The results indicated that perovskite with impurities affected the ionic conductivity and enhanced the capacitive performance of ACs. The capacitance measured on the electrode made of the best performing sample in both three- and two-electrode cell systems in the absence of a conductive agent - carbon black was 270 F g−1 and 185 F g−1 at current density of 0.5 A g−1, respectively. The results suggest that the AC/perovskite composites are promising electrodes of the high-performance supercapacitors.
The hierarchical porous architecture of activated carbons (ACs) from cotton stalks feed are fabricated with the use of TiO2 during activation. The sample shows high surface area and the partly graphitized carbon frameworks. The CaTiO3 perovskite is formed in certain amount, which could effectively accelerate ion and electron transport of ACs. Higher content and lower content of TiO2 catalysts cannot fit to the Ca atoms, leading to either the formation of amorphous TiO2 or less CaTiO3. The electrochemical performance was then restricted with the response of the transfer of ions and electrons. Display omitted
•The ACs from cotton stalk feed was prepared with addition of TiO2.•The perovskite was formed during the activation.•The formation of perovskite was related to the calcium content in the ACs.•The energy density achieved to 22.5 Wh kg−1 at 5065 W kg−1.•The sample possessed high stability of charging-discharging in two electrode system.
Abstract In recent years, there is a growing interest in developing ultralong organic room‐temperature phosphorescence (ORTP) with lifetimes in the range of seconds. As one of the important three ...primary colors, ultralong blue ORTP is an indispensable core component in RTP regulation and application, however, the large Stokes shift characteristics pose certain challenges in developing ultralong blue ORTP. Here, a new family of blue phosphors are synthesized and ultralong blue ORTP are realized through crystal assembly in water and organic phase. Remarkably, compared to crystal materials obtained in organic phases, assembly materials obtained in water enabled long‐lived blue ORTP with lifetimes up to 2.3 s and phosphorescence quantum yield reached as high as 29.27%. In addition to the efficient and green assembly form, such dark blue ORTP materials possessed high thermal stability and flexible tunability. Moreover, the superiority of the selected assembly components is demonstrated by comparing them with polymer assembly and the proposed blue ORTP materials show great potential in an organic programmable information encryption/anti‐counterfeiting.
T-helper (Th) 22 is involved in the pathogenesis of inflammatory diseases. The roles of Th22 cells in the pathophysiological of ankylosing spondylitis (AS) and rheumatoid arthritis (RA) remain ...unsettled. So we examined the frequencies of Th22 cells, Th17 cells and Th1 cells in peripheral blood (PB) from patients with AS and patients with RA compared with both healthy controls as well as patients with osteoarthritis.
We studied 32 AS patients, 20 RA patients, 10 OA patients and 20 healthy controls. The expression of IL-22, IL-17 and IFN-γ were examined in AS, RA, OA patients and healthy controls by flow cytometry. Plasma IL-22 and IL-17 levels were examined by enzyme-linked immunosorbent assay.
Th22 cells, Th17 cells and interleukin-22 were significantly elevated in AS and RA patients compared with OA patients and healthy controls. Moreover, Th22 cells showed positive correlation with Th17 cells as well as interleukin-22 in AS and RA patients. However, positive correlation between IL-22 and Th17 cells was only found in AS patients not in RA patients. In addition, the percentages of both Th22 cells and Th17 cells correlated positively with disease activity only in RA patients not in AS patients.
The frequencies of both Th22 cells and Th17 cells were elevated in PB from patients with AS and patients with RA. These findings suggest that Th22 cells and Th17 cells may be implicated in the pathogenesis of AS and RA, and Th22 cells and Th17 cells may be reasonable cellular targets for therapeutic intervention.
As one of the basic supporting technologies of 5G system, wireless sensor networks technology is facing a new challenge to improve its transmission energy efficiency. This paper considers combining ...simultaneous wireless information and power transfer (SWIPT) technique and routing technique, and applying them to multi-hop clustered wireless sensor networks (MCWSN), where each node can decode information and harvest energy from a received radio-frequency signal. And the relay nodes in MCWSN can utilize the harvest energy to forward data to their next hop nodes according to the routing scheme. First, we formulate an energy-efficient routing problem of MCWSN with SWIPT. Then, a heuristic energy efficient cooperative SWIPT routing algorithm (EECSR) is presented to find a transmission path with the maximum energy efficiency. Specifically, in EECSR, the resource allocation problem in each hop of the path is transformed to some equivalent convex optimization problems, which are resolved via dual decomposition. Moreover, a distributed routing protocol based on EECSR is proposed. As far as we know, this is the first solution that considers energy efficiency optimization based on routing and SWIPT in MCWSN. Simulation results show that our EECSR algorithm has high energy efficiency and good robustness. And our distributed routing protocol has better real-time performance than traditional protocols.
This paper attempts to verify the "inverted U" effect of the income gap on the total factor productivity (TFP) of the country or region by constructing a theoretical model that includes income ...effects and substitution effects. Based on this, this paper uses the multinational panel data of 53 countries in the world from 1995 to 2014 for empirical research. The research shows that: (1) the income gap has an "inverted U-shaped" effect on the national TFP, and the inflection point is located at about 0.269; (2) The income gap is also verified by the "inverted U" influence mechanism of the national TFP by affecting the income effect and the substitution effect; (3) The difference in the development stage determines that countries should adopt an income distribution policy that is compatible with their own country. The conclusions of this paper strengthen the confidence and determination to improve the supply system and promote regional innovation, and confirm the necessity of promoting global economic restructuring and achieving global inclusive development to a certain extent.
P53 is one of the key tumor suppressors. In normal cells, p53 is maintained at low levels by the ubiquitination of the ubiquitinated ligase MDM2. In contrast, under stress conditions such as DNA ...damage and ischemia, the interaction between p53 and MDM2 is blocked and activated by phosphorylation and acetylation, thereby mediating the trans-activation of p53 through its target genes to regulate a variety of cellular responses. Previous studies have shown that the expression of p53 is negligible in normal myocardium, tends to increase in myocardial ischemia and is maximally induced in ischemia-reperfused myocardium, demonstrating a possible key role of p53 in the development of MIRI. In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and describe the therapeutic agents targeting the relevant targets to provide new strategies for the prevention and treatment of MIRI.
We collected 161 relevant papers mainly from Pubmed and Web of Science (search terms "p53" and "myocardial ischemia-reperfusion injury"). After that, we selected pathway studies related to p53 and classified them according to their contents. We eventually analyzed and summarized them.
In this review, we detail and summarize recent studies on the mechanism of action of p53 in MIRI and validate its status as an important intermediate affecting MIRI. On the one hand, p53 is regulated and modified by multiple factors, especially non-coding RNAs; on the other hand, p53 regulates apoptosis, programmed necrosis, autophagy, iron death and oxidative stress in MIRI through multiple pathways. More importantly, several studies have reported medications targeting p53-related therapeutic targets. These medications are expected to be effective options for the alleviation of MIRI, but further safety and clinical studies are needed to convert them into clinical applications.
A nonenzymatic amperometric glucose sensor was established based on the electrocatalytic oxidation of nanoporous gold (NPG) toward glucose. The NPG electrode was prepared by a facile, rapid one-step ...square-wave oxidation reduction cycle (SWORC) within 5min. The prepared NPG electrode had high roughness, excellent electrocatalytic activity toward glucose electrooxidation and was characterized by scan electron microscopy (SEM), atomic force microscope (AFM) and cyclic voltammetry (CV). The CV was also used to evaluate the electrochemical response of the NPG electrode to the glucose oxidation in 0.01molL−1 NaOH solution. Under the optimal conditions, the NPG electrode showed a good linear relationship between the current response signal and the glucose concentrations in a range from 2μmolL−1 to 1.375mmolL−1 and 1.375mmolL−1 to 15mmolL−1 with a detection limit of 0.5μmolL−1 (S/N=3). In addition, the nafion was selected as the protective film to enhance specificity of the developed glucose biosensor, and the physiological levels of ascorbic acid (0.1mmolL−1) and uric acid (0.02mmolL−1) only had negligible interferences to the glucose detection. This new glucose sensor exhibited a fast amperometric response, high sensitivity and selectivity, and it was successfully used to detect the glucose in human serum sample with a satisfactory result.
Patients with diabetes are prone to develop cardiac hypertrophy and more susceptible to myocardial ischemia-reperfusion (I/R) injury, which are concomitant with hyperglycemia-induced oxidative stress ...and impaired endothelial nitric oxide (NO) synthase (eNOS)/NO signaling. Caveolae are critical in the transduction of eNOS/NO signaling in cardiovascular system. Caveolin (Cav)-3, the cardiomyocytes-specific caveolae structural protein, is decreased in the diabetic heart in which production of reactive oxygen species are increased. We hypothesized that treatment with antioxidant N-acetylcysteine (NAC) could enhance cardiac Cav-3 expression and attenuate caveolae dysfunction and the accompanying eNOS/NO signaling abnormalities in diabetes.
Control or streptozotocin-induced diabetic rats were either untreated or treated with NAC (1.5 g/kg/day, NAC) by oral gavage for 4 weeks. Rats in subgroup were randomly assigned to receive 30 min of left anterior descending artery ligation followed by 2 h of reperfusion. Isolated rat cardiomyocytes or H9C2 cells were exposed to low glucose (LG, 5.5 mmol/L) or high glucose (HG, 25 mmol/L) for 36 h before being subjected to 4 h of hypoxia followed by 4 h of reoxygenation (H/R).
NAC treatment ameliorated myocardial dysfunction and cardiac hypertrophy, and attenuated myocardial I/R injury and post-ischemic cardiac dysfunction in diabetic rats. NAC attenuated the reductions of NO, Cav-3 and phosphorylated eNOS and mitigated the augmentation of O
, nitrotyrosine and 15-F2t-isoprostane in diabetic myocardium. Immunofluorescence analysis demonstrated the colocalization of Cav-3 and eNOS in isolated cardiomyocytes. Immunoprecipitation analysis revealed that diabetic conditions decreased the association of Cav-3 and eNOS in isolated cardiomyocytes, which was enhanced by treatment with NAC. Disruption of caveolae by methyl-β-cyclodextrin or Cav-3 siRNA transfection reduced eNOS phosphorylation. NAC treatment attenuated the reductions of Cav-3 expression and eNOS phosphorylation in HG-treated cardiomyocytes or H9C2 cells. NAC treatment attenuated HG and H/R induced cell injury, which was abolished during concomitant treatment with Cav-3 siRNA or eNOS siRNA.
Hyperglycemia-induced inhibition of eNOS activity might be consequences of caveolae dysfunction and reduced Cav-3 expression. Antioxidant NAC attenuated myocardial dysfunction and myocardial I/R injury by improving Cav-3/eNOS signaling.
Lophatherum gracile, an important medicinal plant, is used traditionally in the treatment of cough associated with lung heat and inflammation. In this study, an ethanol extract of L. gracile (DZY) ...was shown to inhibit respiratory syncytial virus (RSV) infection and RSV-induced inflammation in vitro and in vivo. These findings provide a strong and powerful support for the traditional use of L. gracile in the treatment of RSV-related diseases.
To determine the anti-RSV activities of DZY and its ingredients, and explore the relationship between RSV infection and inflammation.
DZY was extracted from L. gracile and its major ingredients were determined by high-performance liquid chromatography (HPLC). RSV-infected HEp-2 and RAW264.7 cell models were established to assess the inhibitory effect of DZY on RSV replication and nitric oxide (NO) production in vitro. Three-week-old BALB/c mice challenged intranasally with RSV were used to establish RSV-infected animal mode. The mice were respectively administered DZY at high-, middle-, and low-dose in different groups. The anti-RSV activity of DZY was evaluated by detecting viral load, lung lesion, CD4+ and CD8+ T cell population, and interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ expression in the lung tissue.
In HEp-2 cell line, DZY effectively inhibited RSV infection in a dose-dependent manner with IC50 values of 20 μg/mL against RSV (Long strain) and IC50 values of 25 μg/mL against RSV (A2 strain). The anti-RSV activity of DZY was mainly determined by isoorientin, swertiajaponin, 3, 5-di-caffeoylquinic acid, and 3, 4-di-caffeoylquinic acid. Moreover, DZY suppressed NO production induced by RSV in vitro. In vivo, oral administration of DZY significantly reduced the viral load and ameliorated lesions in the lung tissue. A probable antiviral mechanism was mediated by slightly improving the ratio of CD4+/CD8+ T cells and inhibiting the mRNA and protein expression of IL-1β, TNF-α, and IFN-γ.
(1) DZY exhibits anti-RSV activities both in vitro and in vivo. (2) RSV infection can trigger a series of inflammatory reactions; thus, ameliorating inflammation is helpful to control the course of disease caused by RSV. These findings provide the rationale and scientific evidence behind the extensive use of L. gracile in traditional medicine for the treatment of diseases potentially caused by RSV.
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