Despite graphene (G) is impermeable to all molecules and with excellent chemical stability, conductive G is cathodic to most metals and can aggravate metal corrosion at exposed metal-coatings ...interfaces. This effect may accelerate dangerous localized corrosion and potentially impedes its applications in metal protection. Here, we present successful synthesis of nonconductive G (FmG) through the Diels-Alder reaction between exfoliated G and a bio-based epoxy monomer, and its application in epoxy (EP) anticorrosive coatings. The FmG as-prepared exhibit well solubility in traditional organic solvents due to the graft of FdE chains on the FmG surface. The corrosion resistances of FmG reinforced EP coatings were investigated by electrochemical tests (open circuit potential, Tafel curves, and impedance) after immersed in a 3.5 wt % NaCl solution. The results demonstrated that embedding 0.5 wt% of FmG in EP coating effectively improves the barrier properties of the coating and shows superior corrosion resistance compared with pure EP. In addition, we also gave the protection mechanisms about the corrosion reaction of G-based modified and unmodified EP coatings. The strategy provides a promise strategy for development of G-based heavy coatings with superior barrier properties for metal protection.
A reasonable graphene molecular design and its advanced application in improve the corrosion resistance performance of epoxy coatings. Display omitted
The unique properties of graphene are highly desired for printing electronics, coatings, energy storage, separation membranes, biomedicine, and composites. However, the high efficiency exfoliation of ...graphene into single- or few-layered nanoplates remains a grand challenge and becomes the bottleneck in essential studies and applications of graphene. Here, we report a scalable and green method to exfoliate graphene nanoplatelets (GNPs) from nature graphite in pure water without using any chemicals or surfactants. The essence of this strategy lies in the facile liquid exfoliation route with the assistance of vapor pretreatment for the preparation of edge hydroxylated graphene. The produced graphene consisted primarily of fewer than ten atomic layers. Such the water soluble graphene can be stored in the form of dispersion (~0.55 g L
) or filter cake for more than 6 months without the risk of re-stacking. This method paves the way for the environmentally friendly and cost-effective production of graphene-based materials.
Flow-electrode capacitive deionization (FCDI) is novel capacitive deionization (CDI) technology that exhibits continuous deionization and a high desalting efficiency. A flow-electrode with high ...capacitance and low resistance is required for achieving an efficient FCDI system with low energy consumption. For developing high-performance flow-electrode, studies should be conducted considering porous materials, conductive additives, and electrolytes constituting the flow-electrode. Here, we evaluated the desalting performances of flow-electrodes with spherical activated carbon and aqueous electrolytes containing various concentrations of NaCl in the FCDI unit cell for confirming the effect of salt concentration on the electrolyte of a flow-electrode on desalting efficiency. We verified the necessity of a moderate amount of salt in the flow-electrode for compensating for the reduction in the performance of the flow-electrode, attributed to the resistance of water used as the electrolyte. Simultaneously, we confirmed the potential use of salt water with a high salt concentration, such as seawater, as an aqueous electrolyte for the flow-electrode.
This nationwide population-based cohort study aimed to investigate the impact of systemic anti-inflammatory treatment on the major adverse cardiovascular events (MACE) risk in patients with psoriasis ...from January 2006 to December 2018, using a database provided by the Korean National Health Insurance Service. Patients were grouped based on the following treatment modalities: biologics, phototherapy, methotrexate, cyclosporine, and mixed conventional systemic agents. Patients who had not received any systemic treatment were assigned to the control cohort. The incidence of MACE per 1000 person-year was 3.5, 9.3, 12.1, 28.4, 39.5, and 14.5 in the biologic, phototherapy, methotrexate, cyclosporine, mixed conventional systemic agents, and control cohorts, respectively. During the 36-month follow-up, the cumulative incidence of MACE in the phototherapy and biologic cohorts remained lower than that of other treatment modalities. Cyclosporine (hazard ratio (HR) = 2.11, 95% confidence interval (CI) = 1.64-2.71) and mixed conventional systemic agents (HR = 2.57, 95% CI = 2.05-3.22) treatments were associated with increased MACE risk. Methotrexate treatment was not associated with MACE. Our finding demonstrates that treatment modalities may affect cardiovascular comorbidities in patients with psoriasis. Thus, an appropriate combination of anti-psoriatic therapies should be considered to manage patients with high cardiovascular risk.IRB approval status: Waiver decision was obtained by the institutional review board, Konkuk University Hospital, Seoul, Republic of Korea (KUH1120107).
This article presents the case of a patient with recurrent chronic diarrhea and cachexia who was misdiagnosed, followed by a literature review to summarize the reasons for misdiagnosis of POEMS ...syndrome and the treatment strategies.
The diagnosis and treatment of this patient suggest that with the improvement of M-protein detection levels, the diagnosis of patients with low M-protein levels, such as those with POEMS syndrome, has been greatly aided.
POEMS syndrome requires polyneuropathy and monoclonal plasma cell proliferation as mandatory diagnostic criteria. Therefore, patients presenting with polyneuropathy should routinely undergo M-protein testing and consider the possibility of POEMS syndrome.
The patient, in this case, was treated primarily with relatively conservative immunomodulatory agents.
During follow-up after treatment, the patient's diarrhea and malnutrition showed significant improvement.
POEMS syndrome has low clinical specificity and a high rate of misdiagnosis. However, once a definitive diagnosis is made, the treatment outcome is favorable.
Hexagonal boron nitride (hBN) with outstanding impermeability and resistivity seems to hold promise as a long-term corrosion barrier for metals. However, the high-yield production of hBN still ...remains a key challenge. Herein, we provide a scalable exfoliation technique to scalable synthesis of hydroxylated boron nitride nanosheets (HBNNS). Then phosphorylated boron nitride (PBNNS) was prepared through in situ phosphate esterification between HBNNS and phosphoric acid. The PBN coatings were fabricated by electrophoretic deposition (EPD) from PBNNS suspensions for metal protection. The excellent corrosion resistance of PBNNS-EPD layers was attributed to the superior barrier property and formed passivation film from PBNNS.
An asymmetric total synthesis of vincadifformine is described. The limited tactics with chiral cation‐directed catalysis in total synthesis inspired the development of our strategy for accessing this ...alkaloid in enantionrich form. The route features a thiourea–phosphonium salt catalyzed Mannich‐type reaction, a phosphine‐promoted aza‐Morita–Baylis–Hillman reaction and a trifluoroacetic acid promoted deprotection/amidation cascade process.
Cascade processes: Asymmetric total synthesis of vincadifformine is described. Our strategy features a thiourea–phosphonium salt catalyzed Mannich‐type reaction, a phosphine‐promoted aza‐Morita–Baylis–Hillman reaction, and a trifluoroacetic acid promoted deprotection/amidation cascade process (see scheme).
Predicting trends in land use/cover change (LUCC) and assessing future ecological security (ES) can help effectively balance regional ecological conservation and economic development. In this study, ...a land use simulation model was used to predict the spatial-temporal variation in land use in Kashgar in 2030 under three scenarios (inertial development, agricultural land protection, and forest and rangeland conservation). Subsequently, by combining the pressure–state–response model and predicted land use, the ES of the Kashgar region in 2000, 2010, and 2020 were evaluated. We found that (1) only agricultural land and built-up land in the Kashgar region increased from 2000–2020 by 4174.79 and 434.44 km2, respectively. (2) The area of the region belonging to a generally safe level or above decreased from 38.36% in 2000 to 36.89% in 2010 and then increased to 37.71% in 2020. (3) In 2030, the ES status under the three scenarios will be improved, among which the agricultural land protection scenario corresponds to the best ES status. This research is valuable for deeply understanding the interaction mechanism between LUCC and ES in typical artificial oases in arid areas of the Kashgar region and sustaining relatively stable internal structures and socioeconomic activities in the arid oasis of the Kashgar region.
Human umbilical cord-derived mesenchymal stem cell (hUC-MSC) engraftment is a promising therapy for acute ischemic stroke (AIS). However, the harsh ischemic microenvironment limits the therapeutic ...efficacy of hUC-MSC therapy. Curcumin is an anti-inflammatory agent that could improve inflammatory microenvironment. However, whether it enhances the neuroprotective efficacy of hUC-MSC transplantation is still unknown. In the present study, we investigated the therapeutic efficacy and the possible mechanism of combined curcumin and hUC-MSC treatment in AIS.
Middle cerebral artery occlusion (MCAO) mice and oxygen glucose deprivation (OGD) microglia were administrated hUC-MSCs with or without curcumin. Neurological deficits assessment, brain water content and TTC were used to assess the therapeutic effects of combined treatment. To elucidate the mechanism, MCAO mice and OGD microglia were treated with AKT inhibitor MK2206, GSK3β activator sodium nitroprusside (SNP), GSK3β inhibitor TDZD-8 and Nrf2 gene knockout were used. Immunofluorescence, flow cytometric analysis, WB and RT-PCR were used to evaluate the microglia polarization and the expression of typical oxidative mediators, inflammatory cytokines and the AKT/GSK-3β/β-TrCP/Nrf2 pathway protein.
Compared with the solo hUC-MSC-grafted or curcumin groups, combined curcumin-hUC-MSC therapy significantly improved the functional performance outcomes, diminished the infarct volumes and the cerebral edema. The combined treatment promoted anti-inflammatory microglia polarization via Nrf2 pathway and decreased the expression of ROS, oxidative mediators and pro-inflammatory cytokines, while elevating the expression of the anti-inflammatory cytokines. Nrf2 knockout abolished the antioxidant stress and anti-inflammation effects mediated with combined treatment. Moreover, the combined treatment enhanced the phosphorylation of AKT and GSK3β, inhibited the β-TrCP nucleus translocation, accompanied with Nrf2 activation in the nucleus. AKT inhibitor MK2206 activated GSK3β and β-TrCP and suppressed Nrf2 phosphorylation in nucleus, whereas MK2206 with the GSK3β inhibitor TDZD-8 reversed these phenomena. Furthermore, combined treatment followed by GSK3β inhibition with TDZD-8 restricted β-TrCP nucleus accumulation, which facilitated Nrf2 expression.
We have demonstrated that combined curcumin-hUC-MSC therapy exerts anti-inflammation and antioxidant stress efficacy mediated by anti-inflammatory microglia polarization via AKT/GSK-3β/β-TrCP/Nrf2 axis and an improved neurological function after AIS.
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