A novel type of graphene oxide (GO)/Nafion composite membrane is fabricated and used as a proton exchange membrane for direct methanol fuel cells (DMFCs) in this article. The membranes are prepared ...by depositing GO nanosheets on the surface of recast Nafion® 117 via a layer-by-layer (LbL) procedure using 1, 4-phenyldiamine hydrochloride (PDHC) as the cross-linker. This approach prevents the GO nanosheets from dissolving in water and imparts the composite membranes a good stability. The methanol permeability of the composite membranes is lower than that of recast Nafion® 117 measured under the same conditions. The composite membrane with 80-layered GO nanosheets exhibits a value of 6.7×10−8cm2s−1 at 30°C, which is two orders of magnitude lower than that of recast Nafion® 117. In addition, the relative selectivity of the composite membranes is 5 times higher than that of recast Nafion® 117. The endurance time of the composite membranes in Fenton׳s reagent is 10 times longer than that of Nafion. Single cell evaluation using the composite membrane with 50-layered GO showed an open circuit voltage (OCV) of 0.67V. A maximum power density of 64.38mWcm−2 at a current density of 200mAcm−2 can be achieved at 60°C.
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•A novel GO/Nafion composite membrane is fabricated by LbL method.•The GO/Nafion composite membranes exhibit low methanol permeability.•The oxidative stability of the composite membrane is enhanced greatly.•The GO layers of the composite membranes can be easily controlled.
Excessive glutamate release has been linked to stress and many neurodegenerative diseases. Evidence indicates abnormalities of glutamatergic neurotransmission or glutamatergic dysfunction as playing ...an important role in the development of many major psychiatric disorders (e.g., schizophrenia, bipolar disorder, and major depressive disorder). Recently, ketamine, an
-methyl-d-aspartate antagonist, has been demonstrated to have promisingly rapid antidepressant efficacy for treatment-resistant depression. Many compounds that target the glutamate system have also become available that possess potential in the treatment of major psychiatric disorders. In this review, we update evidence from recent human studies that directly or indirectly measured glutamatergic neurotransmission and function in major psychiatric disorders using modalities such as magnetic resonance spectroscopy, positron emission tomography/single-photon emission computed tomography, and paired-pulse transcranial magnetic stimulation. The newer generation of antidepressants that target the glutamatergic system developed in human clinical studies is also reviewed.
In this population-based propensity score matched (PSM) cohort study, we aimed to investigate the risk of developing dementia with the use of acid suppressants, including proton pump inhibitors ...(PPIs) and histamine-2 receptor antagonists (H2 antagonists). Cohorts of PPI users (n = 2,778), H2 antagonist users (n = 6,165), and non-users (n = 86,238) were selected from a dataset covering the years 2000 to 2010 in Taiwan's National Health Insurance Research Database. Patients in the three groups were PSM at a ratio of 1:1 within each comparison cohort (CC). Three CCs were created: (1) PPI users compared to non-users (CC1, n = 2,583 pairs); (2) H2 antagonist users compared to non-users (CC2, n = 5,955 pairs); and (3) PPI users compared to H2 antagonist users (CC3, n = 2,765 pairs). A multivariable robust Cox proportional hazard model was used to estimate the adjusted hazard ratio (aHR) and the 95% confidence interval (CI) for the risk of developing dementia. The multivariable analysis results show that the aHR of developing dementia during the follow-up period was 0.72 (CC1: 95% CI = 0.51-1.03, P = 0.07) for PPI users and 0.95 (CC2: 95% CI = 0.74-1.22, P = 0.69) for H2 antagonist users, when compared to non-users. Between the patients using acid suppressants, there was no difference between PPI and H2 antagonist users in the risk of developing dementia (CC3: aHR = 0.82, 95% CI = 0.58-1.17, P = 0.28). In conclusion, no association was observed between the use of acid suppressants and the risk of developing dementia in any of the three CCs. Further, randomized controlled trials are warranted to confirm this relationship.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Objective
SOX9 has been shown to be related to the metastasis of various cancers. Recently, it has been reported that SOX9 plays a regulatory role in lung adenocarcinoma (LUAD) cell ...metastasis, but the specific mechanism remains to be explored. Therefore, the objective of this study was to observe the effect and mechanism of SOX9 on the invasion and migration of LUAD cells.
Methods
RT-qPCR was applied to observe the expression of SOX9 and RAP1 in tumor tissues and corresponding normal lung tissues collected from LUAD patients. Co-immunoprecipitation and Pearson correlation to analyze the expression correlation of SOX9 with RAP1. To observe the role of SOX9, the invasion and migration levels of LUAD A549 cells in each group were observed by Transwell invasion assay and Scratch migration assay after knocking down or overexpressing SOX9. Besides, the expression levels of RAP1 pathway-related proteins (RAP1, RAP1GAP and RasGRP33) were observed by RT-qCPR or western blot. Subsequently, RAP1 was overexpressed and SOX9 was knocked down in A549 cells, and then the cell invasion/migration level and RAP1 pathway activity were assessed.
Results
The expression levels of SOX9 and RAP1 in tumor tissues and A549 cells of LUAD patients were significantly increased and positively correlated. Overexpression of SOX9 or RAP1 alone in A549 cells enhanced the invasion and migration ability of cells, as well as up-regulated the expression levels of RAP1, RAP1GAP and RasGRP33. However, knocking down SOX9 decreased cell invasion and migration levels and weakened the activity of RAP1 pathway. Notably, overexpressing RAP1 while knocking down SOX9 significantly activated RAP1 pathway and promoted cell invasion and migration.
Conclusion
Overexpression of SOX9 in LUAD can significantly activate the RAP1 signaling pathway and promote cell invasion and migration.
Railway level crossings (LCs), as the intersection of road and rail transport, are the weak points in terms of safety, as they are used by different modes of transport. The safety level at LCs can ...therefore be affected by the behaviour of the users. However, the level of safety can also be affected by failures and errors in the operation of LC equipment. Apart from safety, errors and failures of the LC devices can lead to longer waiting times for road users. As the volume of traffic on rail and road increases, so does the risk that the level of safety will decrease. The increase in traffic volume via LC leads to higher traffic volume on the road and more frequent trains on the rail, which leads to longer waiting times for road users on the LCs. The longer waiting times can disrupt the traffic flow, especially during peak hours when the growing volume of traffic on road and rail increases road user dissatisfaction. Moreover, in the era of Industry 4.0 and Digital Rail, new digital and automated technologies are being introduced to improve rail performance and competitiveness. These technologies are aligned with the LCs and are intended to ensure the efficient operation of LC and the efficient use of LCs by conventional trains as well. To achieve this, a concept is needed that simultaneously monitors and visualises the operation of LC in real time, identifies potential faults and failures of the LC equipment, and updates and monitors the proper operation of LC based on the historical data and information of the operation of LC according to the road traffic volume and the characteristics of the rail traffic and trains. Therefore, in this study, a digital twin system (DT) for rail LC was initiated and built as a concept that can meet the above requirements for proper LC operation in real time. DT of LC includes all components of LC and communication between them to synchronise the operation of LC according to the real-time requirements. The DT system is able to optimise the operation time of LC by monitoring the operation of LC and collecting data to ensure efficient use of LC and reduce unnecessary waiting time for road users. In this paper, the operation time of LCs on Swedish and Taiwanese railways was compared using the developed level crossing optimisation model (OLC). Since the introduction of new signalling concepts requires an improvement of LC operating characteristics and their design, the operating strategies were modelled using the OLC model. The results of the work show that the optimal values of LC operation time are different for the case studies investigated. The replacement of track circuits as detection devices and the introduction of balises can also positively influence the operation time, as well as increasing the speed of trains via LCs. However, due to the formulation of the OLC model, the impact of a longer train length on the operation of LC is not recognised. The OLC model can be used to estimate the real-time operation time of LC under different traffic conditions as well as the impact of different changes and extensions of LC.
•ATP treatment delayed the quality loss of postharvest mung bean sprouts.•Antioxidant enzymes were induced to scavenge the ROS by ATP treatment.•Exogenous ATP decreased the expression levels of most ...pectin-related genes.•Atomic force microscopy images revealed pectin degradation in different groups.
The effects of exogenous ATP on the postharvest quality, browning and softening of mung bean (Vigna radiata) sprouts were evaluated. ATP treatment significantly alleviated the quality loss and browning events during the storage of 3 days. It also reduced the oxidant damage by inducing high activities of peroxidase (9.3–13.9%) and superoxide dismutase (8.8–10.3%) which scavenged the reactive oxygen species (ROS) effectively. Transcriptional results indicated that ATP treatment decreased VrPL1, VrPME and VrPG1 gene expression levels more than 2 folds at some time points. Furthermore, the atomic force microscope (AFM) images revealed that the pectin degradation was notably slowed by ATP treatment and the width and height of pectin backbone were better maintained (47.1% and 45.6% higher than control without ATP treatment). The cooperative effects of ROS scavenging and decreased expressions of pectin-related genes might contribute to the deferred pectin deterioration and firmness loss by ATP treatment.
This study tested whether combined hyperbaric oxygen (HBO) and allogenic adipose-derived mesenchymal stem cells (ADMSCs) would be superior to either one for improving the locomotor recovery in rat ...after acute traumatic spinal cord injury (TSCI) in rat. Adult-male Sprague–Dawley rats were equally categorized into group 1 (sham-operated control), group 2 (TSCI), group 3 (TSCI + HBO for 1.5 h/day for 14 consecutive days after TSCI), group 4 (TSCI + ADMSCs/1.2 × 106 cells by intravenous injection at 3 h and days 1/2 after TSCI), and group 5 (TSCI + HBO + ADMSCs), euthanized, and spinal cord tissue was harvested by day 49 after TSCI. The protein expressions of oxidative-stress (NOX-1/NOX-2), inflammatory-signaling (TLR-4/MyD88/IL-1β/TNF-α/substance-p), cell-stress signaling (PI3K/p-AKT/p-mTOR), and the voltage-gated sodium channel (Nav1.3/1.8/1.9) biomarkers were highest in group 2, lowest in group 1, and significantly lower in group 5 than in groups 3/4 (all P <0.0001), but they did not differ between groups 3 and 4. The spinal cord damaged area, the cellular levels of inflammatory/DNA-damaged biomarkers (CD68+/GFAP+/γ-H2AX+ cells), mitogen-activated protein kinase family biomarkers (p-P38/p-JNK/p-ERK1/2), and cellular expressions of voltage-gated sodium channel (Nav.1.3, Nav.1.8, and Nav.1.9 in NF200+ cells) as well as the pain-facilitated cellular expressions (p-P38+/peripherin+ cells, p-JNK+/peripherin+ cells, p-ERK/NF200+ cells) exhibited an identical pattern of inflammation, whereas the locomotor recovery displayed an opposite pattern of inflammation among the groups (all P < 0.0001). Combined HBO-ADMSCs therapy offered additional benefits for preserving the neurological architecture and facilitated the locomotor recovery against acute TSCI.
ZnMn2O4 microtubules (ZMO-MTs) with a mesoporous structure are fabricated by a novel yet effective biomorphic approach employing cotton fiber as a biotemplate. The fabricated ZMO-MT has approximately ...an inner diameter of 8.5 μm and wall thickness of 1.5 μm. Further, the sample of ZMO-MT displays a large specific surface area of 48.5 m2 g–1. When evaluated as a negative material for Li-ion batteries, ZMO-MT demonstrates an improved cyclic performance with discharge capacities of 750.4 and 535.2 mA h g–1 after 300 cycles, under current densities of 200 and 500 mA g–1, respectively. Meanwhile, ZMO-MT exhibits superior rate performances with high reversible discharge capacities of 614.7 and 465.2 mA h g–1 under high rates of 1000 and 2000 mA g–1, respectively. In sodium ion batteries applications, ZMO-MT delivers excellent high discharge capacities of 102 and 71.4 mA h g–1 after 300 cycles under 100 and 200 mA g–1, respectively. An excellent rate capability of 58.2 mA h g–1 under the current density of 2000 mA g–1 can also be achieved. The promising cycling performance and rate capability could be benefited from the unique one-dimensional mesoporous microtubular architecture of ZMO-MT, which offers a large electrolyte/electrode accessible contact area and short diffusion distance for both of ions and electrons, buffering the volume variation originated from the repeated ion intercalation/deintercalation processes.
In this study, long fiber‐reinforced thermoplastics (LFT) and coextrusion are applied to wrap carbon fiber tows in a thermoplastic polyurethane (TPU) outer layer. In this way, the proposed wrapped ...yarns have a sheath–core structure. Scanning electron microscopy observation reveals that TPU and carbon fiber tows form a physical combination that allows TPU to further enhance the tensile strength of carbon fiber tows by 35.87%, which is 19.62 ± 1.88 MPa. The tensile strain of carbon fiber tows also improves. LFT and coextrusion are performed to produce successive carbon fiber tows that can be successfully fabricated into textiles, possessing good fabric flexibility. The technique of carbon fiber tows can be applied to mass production feasibility for the field of carbon fiber composites.
The soft and polar nature of quasi‐2D (PEA)2PbBr4 perovskite, and robust photo‐generated excitons lead exciton‐polaritons and exciton‐polarons as the important phenomena near the band edge for ...application in the lighting aspect. In this work, a convenient methodology is proposed based on the polariton resonant modes in temperature‐dependent (77 K to RT) spectroscopy, and investigate the effect of these quasi‐particles on refractive index dispersion. The large binding energy (≈335 meV) of quasi‐2D excitons is obtained by the reflectance measurements at 77 K. Stable exciton‐polaritons and exciton‐polarons are confirmed by energy dispersions and the observation of self‐trapped exciton‐polaron state, respectively. Furthermore, the large negative thermal‐optic coefficient due to damping effect of exciton‐phonon scattering is observed. The phenomenon is opposite to those observed in conventional semiconductors (e.g., Si, Ge, GaN, AlN, GaAs, AlAs, and ZnO etc.). The observed stable negative thermal‐optic coefficients from 160 K to RT indicate that the quasi‐2D perovskite can be used as a phase compensator for conventional semiconductor materials.
The shrinkage of the energy difference between lower polariton branches (LPs) and upper polariton branches (UPs) proves that oscillator strength decreases when the temperature rises from 77 to 300 K. Therefore, the strong damping effect of exciton‐phonon interactions reduces the oscillator strength when the temperature rises, and further result in the negative thermal‐optic behaviors of quasi‐2D (PEA)2PbBr4 perovskite.
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