Synthesis of large-sized spherical Co-C alloys with soft magnetic properties though a high-pressure solid-state metathesis reaction.

In this work, we report a novel high-pressure solid-state metathesis (HSM) reaction to produce spherical bulk (diameters 2-4 mm) Co-C alloys (Co3C and Co1-xCx). At 2-5 GPa and 1300 °C, C atoms preferentially occupy the interstitial sites of the face-centered cubic (fcc) Co lattice, leading to the formation of metastable Pnma Co3C. The Co3C decomposes above 1400 °C at 2-5 GPa, C atoms infiltrate the interstitial sites of the fcc Co lattice, saturating the C content in Co, forming an fcc Co1-xCx solid solution while the C atoms in excess are found to precipitate in the form of graphite. The Vickers hardness of the Co-C alloys is approximately 6.1 GPa, representing a 19.6% increase compared to hexagonal close-packed (hcp) Co. First-principles calculations indicate that the presence of C atoms in the Pnma Co3C structure leads to a relative decrease in the magnetic moments of the two distinct Co atom occupancies. The Co-C alloys exhibited a soft magnetic behavior with saturation magnetization up to 93.71 emu g-1 and coercivity of 74.8 Oe; coercivity increased as the synthesis pressure rises.

Molten salt synthesis of 1T/2H mixed phase MoS2 for boosting photocatalytic H2 evolution via Schottky junction under EY-sensitized system.

Clean H2 fuel obtained from the photocatalytic water splitting to hydrogen reaction could efficiently alleviate current energy crisis and the concomitant environmental pollution problems. Therefore, it is desirable to search for a highly efficient photocatalytic system to decrease the energy barrier of water splitting reaction. Herein, the 1T/2H mixed phase MoS2 sample with Schottky junction between contact interfaces is developed through molten salt synthesis for photocatalytic hydrogen production under a dye-sensitized system (Eosin Y-TEOA-MoS2) driven by the visible light. In mixed phase MoS2 sample, the photogenerated electrons of 2H-phase MoS2 migrated to the 1T-phase MoS2 are difficult to jump back because of the existence of Schottky barrier, which greatly suppresses the quenching of EY and therefore results in an enhanced hydrogen evolution performance. Therefore, the optimized MoS2 sample (MoS2-350) has an initial hydrogen evolution rate of 213 µmol h-1 and corresponding apparent quantum yield of 36.1 % at 420 nm, far higher than those of pure Eosin Y. It is strongly confirmed by the steady-state/time-resolved photoluminescence (PL) spectra and transient photocurrent response experiments. With the assistance of Density functional theory (DFT) calculation, the function of Schottky junction in photocatalytic hydrogen evolution reaction is well explained. In addition, a new and universal method (SVM curve) of judging oxidation or reduction quenching for photosensitizers is proposed.

Nonsteaming method improves the nutritional value and utilization efficiency of silkworm artificial diets.

Artificial diets for silkworms overcome the seasonal limitations of traditional rearing methods with fresh mulberry leaves. However, the current wet artificial diets, steamed at high temperatures, are not favored by silkworms, and they are cumbersome and challenging to preserve. These conditions adversely affected the development of artificial diet-based sericulture production. In this study, we disinfected dry powder diets with radiation and added distilled water without steaming before use. Then, the nutritional value of finished diets and their impact on silkworm development was assessed. Compared with steamed diets, nonsteamed diets were more attractive to silkworms. Chemical assays showed significantly more essential nutrients for silkworms, including l-ascorbic acid, vitamin B1, vitamin B2, and urease in nonsteamed diets than in steamed diets. Feeding fifth-instar silkworm larvae with nonsteamed diets significantly improved the ammonia utilization efficiency of the diet and increased the cocoon shell rate and diet/silk protein conversion efficiency by 5.9% and 13.3%, respectively. When fed with nonsteamed diets, the abundance of aerobic microorganisms in silkworm intestines increased and the abundance of pathogenic bacteria decreased. Furthermore, the vitality of the silkworm, measured by the dead worm cocoon rate, significantly improved by 16.90%. In summary, preparing sterile wet diets without high-temperature steaming effectively improved the nutritional value of the diet and enhanced silkworm growth.

Chemodynamic therapy agent optimized mesoporous TiO2 nanoparticles for Glutathione-Enhanced and Hypoxia-Tolerant synergistic Chemo-Sonodynamic therapy.

Sonodynamic therapy (SDT) can generate reactive oxygen species to kill cancer cells by activating sonosensitizers under ultrasound (US) irradiation. Nevertheless, its application is greatly limited by low quantum yield of sonosensitizers, high levels of endogenous glutathione (GSH) and tumor hypoxia. Herein, a GSH-activated sonosensitizers with synergistic therapy effect (chemodynamic therapy (CDT) and SDT) are developed by depositing Fe(III)-artemisinin infinite coordination polymers (Fe(III)-ART CPs) in pores of mesoporous TiO2 nanoparticles (NPs). The formed Fe(III)-ART-TiO2 NPs have high sono-induced electron-hole separation efficiency because the deposited Fe(III)-ART CPs can provide isolated intermediate bands to capture sono-induced electrons in TiO2 NPs. Meanwhile, Fe3+ in Fe(III)-ART-TiO2 NPs are reduced to Fe2+ by GSH with oxygen-deficient sites generated to further capture sono-induced electrons in TiO2 NPs. Based on this, the reaction efficiency between water molecules and sono-induced holes is high enough to generate numerous hydroxyl radicals (•OH) without oxygen participated for overcoming tumor hypoxia. Additionally, through consuming GSH, the generated Fe2+ can catalyze ART to produce C-centered free radicals for CDT. Owing to these characteristics, Fe(III)-ART-TiO2 NPs show significant tumor suppression ability and good biocompatibility in vivo. The strategy of using CDT agent to modify sonosensitizers offers new options to improve SDT effect without introducing harmful substances.

Altering Ligand Microenvironment of Atomically Dispersed CrN4 by Axial Ligand Sulfur for Enhanced Oxygen Reduction Reaction in Alkaline and Acidic Medium.

Because of the instability and Fenton reactivity of non-precious metal nitrogen-carbon based catalyst when processing the oxygen reduction reaction (ORR), seeking for electrocatalysts with highly efficient performance becomes very highly desired to speed up the commercialization of fuel cell. Herein, chromium (Cr)-N4  electrocatalyst containing extraterrestrial S formed axial S1 -Cr1 N4  bonds (S1 Cr1 N4 C) is achieved via an assembly polymerization and confined pyrolysis strategy. Benefiting from the adjusting  coordination configuration and electronic structure of the metal center through axial coordination, S1 Cr1 N4 C exhibits enhanced the intrinsic activity (half-wave potential (E1/2 ) is 0.90 V versus reversable hydrogen electrode, RHE) compared with that of CrN4 C and Pt/C catalysts. More notably, the catalyst is almost inert in catalyzing the Fenton reaction, and thus shows the high stability. Density functional theory (DFT) results further reveal that the existence of axial S atoms in S1 Cr1 N4 C moiety has the better ORR activity than Cr1 N4 C moieties. The axial S ligand in S1 Cr1 N4 C moiety can break the electron localization around the planar Cr1 N4  active center, which facilitated the rate-limiting reductive release of OH* and accelerated overall ORR process. The present work opens up a new avenue to modulate the axial ligand type of the single-atoms (SAs) active center to enhance intrinsic SAs performances.

Bioactive cytochalasans from the desert soil-derived fungus Chaetomium madrasense 375 obtained via a chemical engineering strategy.

The chemical engineering of natural extracts has emerged as an effective strategy for the production of diverse libraries of chemicals, making it integral to drug discovery. A chemical engineering strategy based on the epoxidation and ring-opening reactions was used to prepare diversity-enhanced extracts of Chaetomium madrasense 375. Eleven unnatural cytochalasan derivatives (1-11) with unique functional groups, such as amine and isoxazole, were isolated and characterized from these chemically engineered extracts of C. madrasense 375. The identification of these new structures was accomplished through comprehensive spectroscopic analysis, supplemented by synthetic considerations. Notably, compounds 5 and 13-16 displayed potent phytotoxic effects on Arabidopsis thaliana, while compounds 1, 2, 5, 10, and 12 demonstrated inhibitory activities on LPS-induced NO production in RAW264.7 cells. Among them, compound 1 was found to be able to inhibit the upregulated expression of the inducible nitric oxide synthase (iNOS) protein induced by LPS, while also decreasing the production of pro-inflammatory cytokines (IL-6) and influencing the phosphorylation of p38, ERK1/2, and JNK at 100 µM. Our findings demonstrate that the chemical engineering of natural product extracts can be an efficient technique for the generation of novel bioactive molecules.

Tipping Gold Nanobipyramids with Titania for the Use of Plasmonic Hotspots to Drive Amine Coupling.

Designing plasmonic photocatalysts with spatially controlled catalytic sites is an effective strategy to boost the sunlight-driven chemical transformation efficiency through plasmonic enhancement. Herein, we describe a facile method for the synthesis of TiO2-tipped Au nanobipyramids (NBPs) to give (Au NBP)/t-TiO2 nanodumbbells. The surfactant cetyltrimethylammonium bromide concentration is the key factor in the construction of this type of unique nanostructure. The photocatalytic aerobic oxidative coupling of amines using the plasmonic photocatalysts with the dumbbell-like and core@shell structures indicates that the TiO2-tipped ends for the photo-reduction and the exposed adjacent Au surface for the photo-oxidation on (Au NBP)/t-TiO2 can significantly improve the photocatalytic activity. The underlying mechanism of the photocatalytic oxidative coupling of benzylamine over (Au NBP)/t-TiO2 has been thoroughly investigated. Both experimental and simulation results for (Au NBP)/t-TiO2 and (Au nanorod)/t-TiO2 confirm the important effect of the plasmonic hotspots on the enhancement of the photocatalytic activity.

A Novel Evaluation Method of Construction Homogeneity for Asphalt Pavement Based on the Characteristic of Component Distribution.

To effectively evaluate the construction homogeneity of asphalt pavement, the tomography image of a core sample of asphalt pavement was obtained via industrial computed tomography (CT) equipment. According to the characteristics of CT images, an improved separation algorithm based on annular partition and Nobuyuki Otsu (OTSU) threshold segmentation was proposed. Based on the distribution of aggregates, voids and asphalt mortar, and the area ratio of each part in the CT images inside the pavement, a novel evaluation method for the distribution homogeneity of asphalt pavement components was put forward, and the validity of the evaluation index was also verified. The results show that the aggregates, voids and asphalt mortar in CT images can be effectively segmented by annular partition combined with the OTSU threshold separation algorithm. By superimposing the segmented image on the original image, the segmentation and identification effects of aggregates, voids and asphalt mortar in the CT image are confirmed. Compared with a non-segregated specimen, the average values of the horizontal heterogeneity coefficients of high, medium, light and fine-aggregate-segregated mixtures increased by 72.0%, 48.3%, 34.7% and 16.1%, respectively, where the change range is in accordance with the segregation degrees of several mixtures. The indirect tensile strength of fine-aggregate-, light-, medium- and high-segregated asphalt mixtures decreased by 8.3%, 16.7%, 25.0% and 45.8%, respectively, when compared with the non-segregated asphalt mixture. The index of the vertical heterogeneity coefficient has good correlation with the indirect tensile strength of segregated asphalt mixtures. The construction quality homogeneity of asphalt pavement in different regions can be reliably evaluated by the horizontal heterogeneity coefficient and vertical heterogeneity coefficient.

A sustainable one-step strategy for highly graphitized capacitive carbons with hierarchical micro-meso-macro porosity.

Large micropore surface area, superior electrical conductivity and suitable pore size are simultaneously desired characteristics for high-performance capacitive carbons. However, these desired features tend to be mutually competing, and are generally difficult to integrate into a single carbon. Considering this challenge, we developed a sustainable, less time-demanding, pollution-free strategy to construct highly graphitized porous carbon (GPC) by one-step heat-treatment. This approach achieves the need of the abovementioned characteristics for capacitive carbons, wherein potassium ferrate works as both an activating agent and graphitization catalyst to achieve synchronous hierarchical porosity and graphitization of wasted natural wood, and the resultant carbon materials possess a large micropore surface area of 870.4 m2 g-1, a highly graphitic carbon skeleton and a well-interconnected micro-meso-macropore structure. The assembled GPC-based symmetrical capacitors exhibited a satisfactory capacitive performance in different aqueous electrolytes (H2SO4, KOH and Na2SO4), including high specific capacitance, prominent rate capability, satisfactory energy density and good cycle stability. Meanwhile, we compared the contributions of porosity and the graphitized structure to capacitive performance, and porosity was dominant in determining capacitance and the graphitized skeleton had a positive effect in enhancing the capacitive performance. In addition, we established the relationship between the structure of GPC and electrochemical capacitive performance in different aqueous electrolytes, providing a valuable reference for GPC-based supercapacitors in different practical applications. More importantly, this strategy holds great promise to sustainably convert biowaste to high-added-value capacitive carbons for advanced energy storage applications in the future.

Cerium-terephthalic acid metal-organic frameworks for ratiometric fluorescence detecting and scavenging·OH from fuel combustion gas.

Hydroxyl radical (•OH) in fuel combustion gas seriously damages human health. The techniques for simultaneously detecting and scavenging •OH in these gases are limited by poor thermal resistance. To meet this challenge, herein, metal organic frameworks (MOFs) with high thermal stability (80-400 °C) and dual function (•OH detection and elimination) are developed by coordinating Ce ions with terephthalic acid (TA) (Ce-BDC). Due to the reversible conversion between Ce3+ and Ce4+, and the high concentration of Ce3+ on the surface of Ce-BDC MOFs (89.6%), an •OH scavenging efficiency over 90% is realized. Ratiometric fluorescence (I440 nm/I355 nm) detection of •OH with a low detection limit of ∼4 µM is established by adopting Ce ions as an internal standard and TA as an •OH-responsive fluorophore. For real applications, the Ce-BDC MOFs demonstrate excellent •OH detection sensitivity and high •OH scavenging efficiency in gas produced from cigarettes, wood fiber and machine oil. Mouse model results show that the damage caused by •OH in cigarette smoke can be greatly reduced by Ce-BDC MOFs. This work provides a promising strategy for sensitively detecting and efficiently eliminating •OH in fuel combustion gas.

Effect Evaluation of Norepinephrine on Cardiac Function in Patients with Sepsis by Cardiac Ultrasound Imaging.

In order to investigate the therapeutic effect of norepinephrine on patients with sepsis and the effect of echocardiography on the diagnosis of cardiac function in patients with sepsis, 86 patients with sepsis were selected as research objects and randomly divided into two groups. Patients in the control group (N = 43 cases) received conventional treatment (1~15 µg/kg∗min dopamine), and those in the experimental group (N = 43 cases) received conventional treatment+norepinephrine therapy (0.05~0.5 µg∗kg-1/min). The clinical efficacy, cardiac ultrasonography results, and hemodynamic indexes of patients between the two groups were analyzed and compared. The results showed that the total effective rate of treatment in the experimental group (97.7%) was significantly higher than that in the control group (81.4%) (P < 0.05). The maximum, minimum, and average values of mitral valve E peak flow velocity (VEpeak) and left ventricular outflow tract peak flow velocity (Vpeak), respiratory variability of mitral valve E peak flow velocity (ΔVEpeak), and respiratory variability of peak flow velocity (ΔVpeak) were all significantly greater than those of the control group (P < 0.05). The area under the receiver operating characteristic curve (AUC) of ΔVEpeak and ΔVpeak for predicting positive volume response in patients with sepsis was 0.934 and 0.913, respectively; the sensitivity was 0.828 and 0.827; the specificity was 0.936 and 0.893; and the Youden indices were 0.765 and 0.712, respectively. In short, norepinephrine had a high total response rate in patients with sepsis, and echocardiography can well evaluate the effect of norepinephrine on cardiac function in patients with sepsis, which is worthy of further promotion.

Bioinspired Synthesis of ZnO@polydopamine/Au for Label-Free Photoelectrochemical Immunoassay of Amyloid-ß Protein.

Amyloid-ß protein (Aß) is an important biomarker and plays a key role in the early stage of Alzheimer's disease (AD). Here, an ultrasensitive photoelectrochemical (PEC) sensor based on ZnO@polydopamine/Au nanocomposites was constructed for quantitative detection of Aß. In this sensing system, the ZnO nanorod array decorated with PDA films and gold nanoparticles (Au NPs) have excellent visible-light activity. The PDA film was used as a sensitizer for charge separation, and it also was used for antibody binding. Moreover, Au NPs were loaded on the surface of PDA film by in situ deposition, which further improved the charge transfer efficiency and the PEC activity in visible light due to the localized surface plasmon resonance effect of Au NPs. Therefore, in ZnO@polydopamine/Au nanocomposites, a significantly enhanced photocurrent response was obtained on this photoelectrode, which provides a good and reliable signal for early detection of AD. Under the optimized conditions, the PEC immunosensor displayed a wide linear range from 1 pg/mL to 100 ng/mL and a low detection limit of 0.26 pg/mL. In addition, this PEC immunosensor also presented good selectivity, stability, and reproducibility. This work may provide a promising point-of-care testing method toward advanced PEC immunoassays for AD biomarkers.

A Dirac nodal surface semi-metallic carbon-based structure as a universal anode material for metal-ion batteries with high performance.

The rapid development of electronic devices requires high power storage batteries. However, reported 3D carbon-based materials are semiconductors or metals and are used in Li- or Na-ion batteries with low capacities. Thus, it is of interest to discover whether there is a universal semi-metallic material for use in high performance Li-, Na-, and K-ion batteries. Inspired by the recent synthesis of 3D carbon-based materials, in the research reported here, a 3D regular porous structure (bct-C56) is designed using graphene sheets. The porous carbon-based material has mechanical, dynamic, thermal, and mechanical stabilities. Interestingly, bct-C56 exhibits semi-metallic features with two Dirac nodal surfaces with mirror symmetry, as well as high Fermi velocities, indicating high electron-transport abilities. More excitingly, its theoretical capacities are 743.8, 478.2, and 425.0 mA h g-1, with diffusion barriers of 0.05-0.12, 0.07-0.12, and 0.03-0.05 eV, average OCVs of 0.31, 0.45, and 0.59 V, and volume expansion levels of 1.2%, 0.02%, and 3.1%, in Li-, Na-, and K-ion batteries, respectively. All these excellent characteristics suggest that semi-metallic bct-C56 is a universal anode material for use in metal-ion batteries with a fast charge-discharge rate. In this research, not only was a new material with a Dirac nodal surface feature designed, but it also offers an approach for the creation of high performance and universal metal-ion battery anodes with 3D porous carbon materials.

Plasmon-enabled N2 photofixation on partially reduced Ti3C2 MXene.

Benefiting from the superior conductivity, rich surface chemistry and tunable bandgap, Ti3C2 MXene has become a frontier cocatalyst material for boosting the efficiency of semiconductor photocatalysts. It has been theoretically predicted to be an ideal material for N2 fixation. However, the realization of N2 photofixation with Ti3C2 as a host photocatalyst has so far remained experimentally challenging. Herein, we report on a sandwich-like plasmon- and an MXene-based photocatalyst made of Au nanospheres and layered Ti3C2, and demonstrate its efficient N2 photofixation in pure water under ambient conditions. The abundant low-valence Ti (Ti(4-x)+) sites in partially reduced Ti3C2 (r-Ti3C2) produced by surface engineering through H2 thermal reduction effectively capture and activate N2, while Au nanospheres offer plasmonic hot electrons to reduce the activated N2 into NH3. The Ti(4-x)+ active sites and plasmon-generated hot electrons work in tandem to endow r-Ti3C2/Au with remarkably enhanced N2 photofixation activity. Importantly, r-Ti3C2/Au exhibits ultrahigh selectivity without the occurrence of competing H2 evolution. This work opens up a promising route for the rational design of efficient MXene-based photocatalysts.

AKR1C1 alleviates LPS­induced ALI in mice by activating the JAK2/STAT3 signaling pathway.

Acute lung injury (ALI) is a respiratory tract disease characterized by increased alveolar/capillary permeability, lung inflammation and structural damage to lung tissues, which can progress and transform into acute respiratory distress syndrome (ARDS). Although there are several treatment strategies available to manage this condition, there is still no specific cure for ALI. Aldo­keto reductase family 1 member C1 (AKR1C1) is a member of the aldo­keto reductase superfamily, and is a well­known Nrf2 target gene and an oxidative stress gene. The aim of the present study was to investigate the effects of AKR1C1 on a lipopolysaccharide (LPS)­induced ALI model. After mice received LPS treatment, the mRNA expression levels of AKR1C1 in the bronchoalveolar lavage fluid and serum were measured using reverse transcription­quantitative PCR and its relationship with the inflammatory factors and malondialdehyde levels were determined using correlation analysis. Next, AKR1C1 was overexpressed or knocked out in mice, and subsequently ALI was induced in mice using LPS. The severity of ALI, oxidative stress and inflammation in the lungs were measured, and the potential involvement of the Janus kinase 2 (JAK2)/signal transduction activator of transcription 3 (STAT3) signaling pathway was assessed by measuring the changes of lung injury parameters after the agonists of JAK2/STAT3 pathway, including interleukin (IL)­6 and colivelin, were administrated to mice. The results revealed that AKR1C1 expression was decreased in the LPS­induced ALI mouse model. AKR1C1 expression was inversely correlated with serum tumor necrosis factor­α, IL­6 and malondialdehyde levels, and positively correlated with serum IL­10 levels. AKR1C1 overexpression significantly attenuated lung injury, as shown by the changes in Evans blue leakage in the lung, lung wet/dry weight ratio, PaO2/FIO2 ratio, survival rate of mice and histological lung changes. In addition, the JAK2/STAT3 signaling pathway was significantly deactivated by AKR1C1+/+. When AKR1C1+/+ mice were treated with JAK2/STAT3 agonists, the effects of AKR1C1 overexpression on lung injury and oxidative stress were abolished. In conclusion, AKR1C1 may protect against oxidative stress and serve as a negative regulator of inflammation in ALI/ARDS. In addition, the JAK2/STAT3 signaling pathway could participate in the protective effects of AKR1C1 against ALI.

Auxetic Carbon Honeycomb: Strain-Tunable Phase Transitions and Novel Negative Poisson's Ratio.

Auxetic structure and tunable phase transitions are fascinating properties for future application. Herein, we propose two three-dimensional (3D) carbon honeycombs (CHC), known as Cmcm -CHC and Cmmm-CHC. Based on first-principles calculations, these novel 3D materials exhibit auxeticity with a fascinating negative Poisson's ratio, which stems from (i) the puckered structure of Cmcm -CHC along the tube axis and (ii) significant change of angle-dominant deformation for Cmmm-CHC in the armchair direction. In addition, the moderate strain drives semimetal to semiconductor phase transition in CHCs, which thoroughly establishes its C-C bond formation. In the meantime, two new phases, namely P63/mmc-CHC and P6/mmm-CHC, form and exhibit semiconductor characteristics. Our results also show that Cmcm -CHC and P63/mmc-CHC are superhard materials. The outstanding negative Poisson's ratio and phase transition properties make CHCs highly versatile for innovative applications in microelectromechanical and nanoelectronic devices.

Transcranial photobiomodulation prevents PTSD-like comorbidities in rats experiencing underwater trauma.

Maladaptive fear memory processing after a traumatic event is a major contributor to the development of the comorbidities related to posttraumatic stress disorder (PTSD). An intervention to normalize this process could be a first-line treatment to prevent PTSD development. However, little progress has been made in identifying interventions that can prevent trauma survivors from developing PTSD. A treatment that could help trauma survivors cope with traumatic memories and decrease the prevalence of PTSD is thus in high demand. This study was designed to investigate the potential beneficial effects of early photobiomodulation (PBM) interventions to prevent PTSD-like comorbidities in animals. PTSD-like comorbidities in rats were induced by an underwater trauma (UWT) procedure, followed by multiple swimming sessions on later days for memory recall. Immediately after UWT and swimming, rats were restrained with or without PBM treatment (808 nm, 25 mW/cm2, 3 J/day). PTSD-like commodities, such as anxiety-like behavior, depression-like behavior, and cognitive dysfunction, were reproduced in UWT-rats. These comorbidities, however, could be prevented by early PBM interventions. By measuring the expression of immediate early genes (IEGs) as neuronal activity markers, we found that PBM treatment differentially regulated Arc and c-fos expression in the hippocampus and amygdala, two PTSD-related brain regions. Additionally, PBM boosted ATP production and regulated protein expression in the hippocampus following stress. Our results demonstrate that PBM can modulate brain activity in response to traumatic and stressful events and that early PBM intervention can prevent the occurrence of PTSD-like comorbidities in rats.

Curcumin ameliorates ischemic stroke injury in rats by protecting the integrity of the blood-brain barrier.

The blood-brain barrier (BBB) is critical for proper cerebral homeostasis and its dysfunction during ischemic stroke can result in significant neurological injury. The major goal of the present study was to identify whether curcumin pretreatment possessed protective effects on BBB integrity during the 24 h of acute ischemic brain injury. To investigate the protective effects of curcumin, male Sprague-Dawley rats were divided into multiple groups, including sham, middle cerebral artery occlusion/reperfusion (MCAO/R) vehicle and curcumin pretreated MCAO/R groups. The effects of curcumin were measured by analyzing neurological deficits, infarct size, BBB permeability and expression levels of permeability-related proteins in the brain. It was found that curcumin pretreatment significantly improved neurological scores, decreased infarct size, and protected synaptic remodeling of hippocampal neurons and upregulated the protein expression level of tight junction proteins, ZO-1, occludin and claudin-5 in ischemic rat brains. Furthermore, curcumin pretreatment before stroke was shown to downregulate the phosphorylation of NF-κB and MMP-9, which are central mediators of inflammation. The results from the present study indicated that curcumin pretreatment ameliorated ischemic stroke injury by protecting BBB integrity and synaptic remodeling, as well as inhibiting inflammatory responses.

Copper ions-assisted inorganic dynamic porogen of graphene-like multiscale microporous carbon nanosheets for effective carbon dioxide capture.

The superior ultramicroporosity and enriched surface CO2-philic sites are simultaneously required features for high-efficiency carbon-based CO2 adsorbents. Unfortunately, these characteristics are usually incompatible and difficult to integrate into one porous carbon material. Herein, we report a new copper ions (Cu2+)-assisted dynamic porogen to construct hierarchically microporous carbon nanosheets in a large scale with high heterogeneity for solving such issue. Cu2+ can be equably dispersed in precursor by coordination interactions of COO-Cu and Cu-N, which can anchor more N/O-containing species in final product. The reduced cuprous ions (Cu+) in pyrolysis process functions as a dynamic porogen to tailor uniform ultramicropores. Importantly, copper salt extracted in this synthetic procedure allows cyclic utilization, realizing a green and low-cost process. The obtained carbon sheets possess a graphene-like morphology, a high surface area and a high-proportioned multiscale microporosity, especially a high-density ultramicropores of 0.4-0.7 nm and supermicroproes of 0.8-1.5 nm. The maximized synergistic effect of morphology, high density of multi-sized ultramicroporosity and surface high heterogeneity endow the resultant microporous carbon nanosheets with the remarkable CO2 capture property, including a high uptake, a moderate adsorption heat, a good selectivity and superior recyclability.