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The search for ultrafast and simple methods to fabricate non-noble metal catalysts to boost electrocatalytic oxygen reduction reaction (ORR) is still ongoing. Herein, we demonstrate a one-step microwave-assisted heating method to prepare copper nitride/iron/iron carbide nanoparticle hybrids (CuNC/Fe/Fe3C/CNT). This ultrafast heating method induces plentiful carbon-wrapped metal and Fe3C nanoparticles that are attached to the surface of CNT and scattered nanosheets. The CuNC/Fe/Fe3C/CNT exhibit a half-wave potential (E1/2) of 0.886 V toward the ORR in alkaline solution, with 220 mV more positive E1/2 than that of CuNC/CNT and Fe/Fe3C/CNT respectively. The activity of as-prepared catalysts is discussed by investigating their structures and compositions and their relationship with the ORR performance. Detailed analysis results disclose that the high activity of the CuNC/Fe/Fe3C/CNT catalysts could be attributed to the interaction of CuNC and Fe/Fe3C species. To be specific, as the electron donor, Fe/Fe3C nanoparticles induce electron localization and promote the formation of Cu (δ + )–NC (0

Herein, a label-free fluorescent signal amplification system based on a catalyzed hairpin assembly (CHA) is reported. In this system, two hairpin probes, H1 and H2, were well-designed in which G-quadruplex sequences were integrated into H2. The CHA reaction was triggered by target/trigger DNA and G-quadruplex sequences were released, which can bind the fluorescent amyloid dye thioflavin T (ThT) to provide fluorescence signals. At the same time, target/trigger DNA was released from the product of the CHA reaction (H1–H2), which continued to initiate the next CHA cycle, and the signal was eventually amplified. This signal amplification approach has been successfully used to develop a label-free fluorescent sensing platform for sensitive detection of human immunodeficiency virus (HIV) DNA and Pb2+.

Silicon (Si) has been considered as the most potential anode material for next-generation high-energy density lithium-ion batteries (LIBs) because of its extremely high theoretical capacity. However, the performance deterioration caused by volume change and low electrical conductivity of active Si particles greatly limit its commercial use. Here, we designed a nonstoichiometric TiO

Exploring the relationships between the composition or morphology of a catalyst and its performance is important in the design of efficient catalysts. Herein, a unique FeCO3@IF electrode, comprising FeCO3 cubes grown on iron foam (IF), is prepared via the regulation of the iron source. During oxygen and hydrogen evolution reactions (OER and HER), the FeCO3 compounds on FeCO3@IF can transform in situ into efficient active sites for the OER (iron oxo/hydroxide nanosheet arrays) and HER (zero-valent iron nanorod arrays coated with FeOx). Meanwhile, the in situ formed vertically aligned arrays improve electron transport and the diffusion of bubbles, compared with accumulated nanoparticles and interlaced nanowires on Fe3O4@IF and Fe–O–M@IF, respectively. Therefore, FeCO3@IF shows high catalytic activity and robust stability for the OER and HER. Furthermore, the transformation of the surface morphology of ferrous carbonate during the catalytic process was observed. Importantly, this work provides a new method to prepare efficient catalytic materials with hierarchical structures via surface in situ self-reconstruction induced by carbonate leaching.

A hybrid host combined with rigid and flexible structural moieties to confine sulfur species physically and chemically is designed and applied for the lithium-sulfur battery. The self-assembled graphene aerogel with nano-MnO2 modified walls serves as the rigid sulfur container while the cross-linked PVP-PVA interpenetrating network acts as the flexible polysulfide trap. The synergic actions enable the hybrid host to present not only good electronic and ionic 3D transfer pathways, but also superior physical and chemical sulfur confinement. Consequently, the MGPP@S composite cathode exhibits excellent electrochemical energy storage performance. It shows initial discharge capacity of 1492, 1054, 833, 659 mAh g−1 at 0.1C, 0.2C, 0.5C, 1C, respectively; meantime it retains a capacity over 755 mAh g−1 during 250 cycles at 0.2C and only has 0.06% capacity decay per cycle during 500 cycles at 1C. The major capacity decay on first several cycling is accounted for sulfurous consumption in saturating the electrolyte and building the interfacial layer; afterwards, the composite electrode can perform consistent capability upon extending cycling.

Developing low-cost high-performance cathode materials for Li-ion batteries is highly desirable. FeOF is considered to be one of the most promising candidate cathode materials for high-performance Li-ion batteries, because of its high capacity and relatively high working potential. Herein, three-dimensional (3D) iron oxyfluoride/N-doped carbon (FeOF/NC) hybrid nanocomposites have been successfully fabricated through a facile solvothermal method combined with a wet ball-milling approach. The uniqueness of this study is that the prepared nanocomposites retain 3D hierarchical structures after wet ball-milling and the materials are doped with nitrogen. The results demonstrate that FeOF nanoparticles are well-dispersed in the 3D interconnected porous NC matrix with a nitrogen doping content of 1.23 at%, where the NC not only provides a strong conductive network facilitating electron and ion transfer, but also accommodates the volume variation during the repeated discharge/charge cycles, thus leading to superior electrochemical performance for the 3D FeOF/NC electrode. When evaluated as cathodes for LIBs at room temperature, 3D FeOF/NC nanocomposites deliver a high reversible capacity of 316 mA h g−1 at 0.05 A g−1 in the voltage range of 1.5–4.0 V, as well as a robust rate performance obtaining 184 mA h g−1 at 2 A g−1. Furthermore, a stable capacity of 191 mA h g−1 can still be retained even at 1 A g−1 after 300 cycles.

Lithium metal batteries are being explored in meeting ever-increasing energy density needs. Because of serious dendritic lithium issues in liquid-state electrolytes, it is generally thought that solid-state electrolytes are potential alternatives for lithium metal batteries. Herein, we design a new single lithium-ion conducting lithium poly[(cyano)(4-styrenesulfonyl)imide] (LiPCSI) to replace the conventional dual-ion conducting salt for use in solid polymer electrolytes (SPEs) that successfully suppress the growth of lithium dendrites. Owing to highly delocalized anion moiety and oxidation-resistant cyano group, the tailored PEO8-LiPCSI SPE exhibits extremely high Li+ transference number (0.84) as well as oxidation potential (5.53 V vs Li+/Li). The symmetric Li/PEO8-LiPCSI/Li cell runs for 1000 h at 60 °C without a short circuit. The rechargeable solid-state Li/PEO8-LiPCSI/LiFePO4 cell discharges a capacity of 141 mAh g-1 with retention over 85% during 80 cycles. These merits enable the proposed PEO8-LiPCSI SPE to be very promising for solid-state lithium metal battery applications.

In this contribution, we optimize the structure of double-input capacitively coupled contactless conductivity detector (DIC4D) that proposed before by our group and successfully applied it in the capillary electrophoresis of inorganic ion analysis. Furthermore, we present the detail theoretical analysis and simulation to exploring the working mechanism of DIC4D. Compared with C4D, under identical experimental conditions and by using the same current-to-voltage converter, both the theoretical and experimental results suggest that the effectiveness and feasibility of DIC4D. The improved DIC4D diminished the baseline drift effects in C4D, provides lower noise, higher sensitivity and notably stable baseline. The LODs of DIC4D are 1.0 μM for K+ and 1.5 μM for Li+ (S/N = 3). DIC4D provides a better linear relationship (R = 0.997 and 0.998 for K+ and Li+, respectively) with the range of 2.0 μM ~ 2.5 mM.

Inappropriate activation of the renin-angiotensin-aldosterone system (RAAS) is an important factor in the development of hypertension. Excessive aldosterone can lead to myocardial extracellular matrix collagen proliferation, fibrosis, and cardiomyocyte hypertrophy and aggravate maladaptive remodeling. The results of our previous clinical and animal experiments suggested that Zi Shen Huo Luo Formula (ZSHLF) combined with perindopril can effectively control the process of left ventricular hypertrophy (LVH). The purpose of this study was to investigate whether ZSHLF-treated serum inhibits the membrane localization of the striatin-mediated mineralocorticoid receptor (MR) and affects MR-mediated nongenomic effects and the downstream epidermal growth factor receptor (EGFR)/extracellular regulated kinase (ERK) signaling pathways, thereby improving aldosterone-induced myocardial remodeling. Serum containing ZSHLF was prepared and used to treat rat cardiomyocytes and cardiac fibroblasts in vitro after aldosterone induction and striatin knockdown by small interfering RNA (siRNA). Cell-based assays were carried out to determine the cardiomyocyte surface area and assess the proliferation rate and hydroxyproline secretion of cardiac fibroblasts. Quantitative real-time PCR (qRT-PCR), immunoprecipitation (IP), and Western blotting were performed to evaluate the striatin-mediated MR/EGFR/ERK signaling pathway. In the present study, ZSHLF attenuated the aldosterone-induced hypertrophy of cardiomyocytes and inhibited the proliferation and collagen synthesis of cardiac fibroblasts. ZSHLF also reduced striatin mRNA expression and inhibited striatin and MR binding, membrane MR protein expression, and EGFR and ERK1/2 phosphorylation. Furthermore, after striatin silencing with siRNA, some of the effects of ZSHLF were not changed significantly. In conclusion, ZSHLF inhibits the downstream EGFR/ERK signaling pathway by blocking the striatin-mediated membrane localization of MR, which may be an important molecular mechanism by which ZSHLF improves aldosterone-induced myocardial remodeling.

It is known that most of the refractory ore are the basis of national economy and widely applied in various fields, however, the complexity of the chemical composition and the diversity of the crystallinity in the mineral phases make the sample pre-treatment of refractory ore still remains a challenge. In this work, the complete decomposition of the refractory ore sample can be achieved just by exposing the solid fusion agent and the refractory ore sample in the microwave irradiation environment for a few minutes, and induced by a drop of water. A digestion time of 15 min for 3.0 g solid fusion agent mixture of sodium peroxide/sodium carbonate (Na2O2/Na2CO3) in a corundum crucible via microwave heating is sufficient to decompose 0.1 g refractory ore sample. An excellent microwave digestion solid agent should meet the following conditions, a good decomposition ability, an outstanding ability of absorbing microwave energy and converting it into heat quickly, a higher melting point than the decomposing temperature of the ore sample. In the research, the induction effect of water plays an important role for the microwave digestion. The energy which is released by the reaction of water and the solid fusion agent (Na2O2) is the key to decompose refractory ore samples with solid fusion agent, which replenished the total energy required for the microwave digestion and made the microwave digestion completed successfully. This microwave digestion technique has good reproducibility and precision, RSD % for Mo, Fe, Ti, Cr and W in the refractory ore samples were all better than 6, except RSD % for Be of about 8 because of the influence of matrix-effect. Meanwhile, the analysis results of the elements in the refractory ore samples provided by the microwave digestion technique were all in good agreement with the analysis results provided by the traditional fusion method except for Cr in the mixture ore samples. In the study, the non-linear dependence of the electromagnetic and thermal properties of the solid fusion agent on temperature under microwave irradiation and the selective heating of microwave are fully applied in this simple microwave technique. Comparing to the traditional fusion decomposition method, this microwave digestion technique is a simple, economical, fast and energy-saving sample pre-treatment technique.

Electrochemical water splitting involves two half-cell reactions, that is oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), and the overall reaction is severely restricted by the OER sluggish kinetics. Hence, to design and develop superior active and low-cost OER electrocatalyst is of significant necessary. In this study, the bimetallic cobalt-iron phosphates nanosheets (denoted as Co-Fe-P-O) with high activity toward OER has been constructed via a rapid microwave-assisted process using sodium hypophosphite and ethylene glycol as the phosphorus source and reaction solvent, respectively. Due to the structural feature of a larger electrochemical active surface area, the catalyst exerts a small overpotential of 267 mV at a current density of 10 mA cm−2 and a low Tafel slope of 30 mV dec−1 in 1.0 M KOH solution. The as-prepared catalyst also shows an outstanding stability with a current density retention of 94% at a constant water oxidation for almost 10 h. All of the results suggest that the performance of the catalyst prepared in our work is better than the state-of-the-art commercial RuO2 and even can rival most of transition metal-based material.

As potential catalytic materials for the oxygen evolution reaction, abundant and eco-friendly iron-based materials are often limited by inferior electrical conductivity. Herein, we propose a cost-effective and facile strategy to prepare a Fe/C heterostructured composite (Fe/Fe3C–F@CNT) via ultra-fast pyrolysis of ferrocene based on the induction and microwave thermal effect of multiwalled carbon nanotubes (CNTs). Fe/Fe3C–F@CNT exhibits a novel heterostructure where carbon-encapsulated Fe/Fe3C nanoparticles are uniformly distributed on the surface of CNTs and small iron-based nano-clusters exist on the surface of carbon layer, thus improving the electrical conductivity and dispersion of active sites. Fe/Fe3C–F@CNT shows superior OER catalytic performance, which is better than that of many Co- and Ni-based catalysts and even superior to that of RuO2. Furthermore, the catalytic performance further improved by loading Fe/Fe3C–F@CNT on the commercial foam iron. The resultant composite required a low overpotential (286 mV) to reach the current density of 10 mA cm−2. The durable catalytic stability, exhibiting no significant degradation at 100 mA cm−2 after 320 h, makes Fe/Fe3C–F@CNT a promising efficient, low-cost and environmentally-friendly OER catalyst for application in water electrolysis and metal–air batteries. More importantly, this study greatly shortens the preparation time required to fabricate uniform Fe/C heterostructures. This study brings a new inspiration for fabricating various materials for application as green energy sources.

Rapid preparing unique carbon-based carriers via simple, low-cost and eco-friendly synthetic strategies benefits for the design of efficient catalysts and their commercial application. In this work, the Fe/C@CNT carrier that the carbon-coated Fe/Fe3C nanoparticles (iron-carbon heterostructure) uniformly growing on carbon nanotube (CNT) is obtained via the fast pyrolysis (only 3 min) of ferrocene on CNT with efficient microwave thermal effect. The unique heterostructure improves the dispersity and stability of Ni, Ru-based compounds on Fe/C@CNT carrier during the fast preparation progress of Ni-Ru@Fe/C@CNT catalyst and the subsequent catalytic reaction processes, and promotes the formation of efficient active sites for HER (Ru (0)) and OER (Ni (3 + )). Therefore, Ni-Ru@Fe/C@CNT shows robust bifunctional activity and enduring stability, and just needs the low overpotential about 32 mV and 246 mV to reach the current density of 10 mA cm−2 for HER and OER, respectively, which are better than the Ni-Ru-Fe@CNT using smooth CNT as carrier and even far superior to the commercial Pt/C and RuO2. More importantly, the whole preparation process of Ni-Ru@Fe/C@CNT is fast, simple and low-cost, providing a facile and environment friendly strategy to rapidly prepare efficient catalysts.

Zn-air battery, as an ideal energy conversion and storage device, is always limited by the expensive and less-than-ideal air electrode materials. The coupling of outstanding oxygen evolution reaction (OER) active sites (oxides derived from Co-Fe nitrides) and superior oxygen reduction reaction (ORR) active centers (metal-N-C and graphitic N) to acquire high-performance and low-cost catalysts is an ideal solution. Herein, we have successfully combined cobalt-iron bimetallic nitrides with N-doped multi-walled carbon nanotubes (Co-Fe-N@MWCNT) as a robust bifunctional material. Benefiting from the synergistic effect between Co, Fe and MWCNTs, Co-Fe-N@MWCNT not only possesses large electrochemically active surface area and effective transport path, but also realizes the integration of superior OER and ORR active sites. Only a low overpotential (290 mV) is needed to achieve a current density of 10 mA cm -2 for OER and the ORR catalytic activity is close to that of the commercial Pt/C. Additionally, Co-Fe-N@MWCNT as an ideal air electrode material can also be applied in Zn-air battery, which exhibits low voltage drop and favorable stability. The voltage gap has a slight change (about 0.03 V) even after 100 cycles of galvanostatic charge-discharge. More importantly, the synthetic strategy in our work may facilitate the design of more high-efficient bifunctional catalysts in various domains.

Layer sodium-based manganese oxides are one of potentially applicable sodium-ion battery (SIB) cathode materials mainly because of their lower cost and relatively reversible Na+ intercalation/extraction attributes. However, unavoidable Jahn-Teller effect arisen from manganese redox reactions causes serious lattice distortion, leading to distinct capacity fade. NaxMnO2 (x

Fe-N-C composite catalyst was prepared by thermal decomposition of chelate precursors based on Fe(III) central ions and o-phenylenediamine ligands. Scanning electron microscopy characterization showed that the crumpled carbon micro- and nano-sheets were intertwined and formed a free-standing tremella-like 3D structure. Notrogen adsorption/desorption experiments revealed that the composite contained ample micro-pores and meso-pores and had a specific surface area of 290 m2 g−1. Graphitic carbon and multi-crystal Fe3C as main components were confirmed by X-ray diffraction, and N-doping in the general form of graphite-N and pyridine-N was also verified by X-ray photoelectron spectroscopy. The electrochemical measurements showed that the tremella-like Fe-N-C composite catalyzed oxygen reduction through a four-electron path in an alkaline solution, and its activity was comparable to that of the commercial Pt/C catalyst. After 2000 cycles, the limiting current density of the Fe-N-C catalytic electrode only decreased less than 5%, and the half-wave potential negatively shifted 5 mV, suggesting that the Fe-N-C composite catalyst had better catalytic stability than the commercial Pt/C catalyst.

Chronic subdural hematoma (CSDH) is an inflammatory angiogenic disease. It is believed that vascular endothelial growth factor (VEGF) plays an important role in pathological CSDH angiogenesis.In this study, magnetic resonance imaging (MRI) results were used to assign 115 primary CSDH patients to four MRI types. The four MRI types are described as follows: type 1 (T1-weighted low, T2-weighted low), type 2 (T1-weighted high, T2-weighted low), type 3 (T1-weighted mixed, T2-weighted mixed), and type 4 (T1-weighted low/high, T2-weighted high). The four MRI types were then correlated with CSDH stage and patient hematoma fluid and serum VEGH concentrations that were measured using an enzyme-linked immunosorbent assay (ELISA). Neurological status was assessed by Markwalder scoring at admission and six-month follow-up.The mean VEGF concentration was significantly higher in CDSH hematoma fluid samples than in patient sera (p0.01). In unilateral CSDH hematoma fluid samples, VEGF concentration was highest in type 1 (21,613.5±1473.3pg/ml), next highest in type 2 (18,071.8±1737.1pg/ml), lower in type 3, and lowest in type 4 patients (13,153.7±3854.4pg/ml, 7265.7±726.2pg/ml, respectively). High VEGF concentrations strongly correlated with MRI type (unilateral CSDH group r=0.838, bilateral CSDH group r=0.851, p0.01). Moreover, higher hematoma fluid VEGF concentrations correlated with markedly higher recurrence in type 1 (3/19, 15.8%) vs. type 4 unilateral CSDH patients (1/27, 3.7%).The present study reports a significant correlation between CSDH hematoma fluid VEGF concentration and MRI results. Therefore, MRI results could be used to predict hematoma fluid VEGF concentrations in CSDH patients.

Iron-based fluorides are considered to be one of the most promising candidate cathode materials for high-performance Li-ion batteries due to their large capacities and high working potential. In this work, a three-dimensional (3D) hybrid nanocomposite of Fe2F5*H2O (FF) loaded in N-doped porous carbon (NPC) is successfully synthesized by a facile and scalable ionic liquid based precipitation followed by a mild heat treatment strategy. The 3D Fe2F5*H2O@NPC (FFNPC) nanocomposite with a hierarchical framework utilized as cathode delivers a high reversible capacity of 185 mAh g-1 at 0.25 C (1 C = 200 mA g-1) and 163 mAh g-1 at 0.5 C in the voltage range of 1.7-4.5 V (vs. Li/Li+) at room temperature. Moreover, the 3D FFNPC cathode shows a robust long-term cycling stability, maintaining 118 mAh g-1 after 200 cycles even at 2 C. The rate performance is also displayed, showing specific capacity of 115 mAh g-1 at high current rate of 5 C. The improved electrochemical properties of 3D FFNPC cathode can be attributed to the combination of the small-sized iron fluoride nanoparticles and the NPC matrix, which not only provides a large surface area for the reaction, but also shortens the diffusion length for Li+ and increases the electrical conductivity.

Electrochemical water splitting in an alkaline electrolyte for large-scale hydrogen production is currently a hot research topic. However, developing high-performance and durable oxygen-evolving electrocatalysts is an ongoing challenge. In this work we prepared Ni-phytate thin films with a bubble-like structure on Ni-foam through an in situ growth process. The resulting material can be used as an oxygen-evolving electrode in basic media without requiring the use of a conductive binder. The Ni-phytate electrode has high catalytic activity (ηj=10mAcm−2=280mV) and good stability (the current activity remained 95% after 5 h) towards OER. This is an effective approach to simplifying the large-scale preparation of catalysts for water-splitting applications. Keywords: Oxygen evolution reaction, In situ formation, Ni-phytate, Sodium phytate, Water oxidation

A new detector, silvering detection window and in-capillary optical fiber light-emitting diode-induced fluorescence detector (SDW-ICOF-LED-IFD), is introduced for capillary electrophoresis (CE). The strategy of the work was that half surface of the detection window was coated with silver mirror, which could reflect the undetected fluorescence to the photomultiplier tube to be detected, consequently enhancing the detection sensitivity. Sulfonamides (SAs) are important antibiotics that achieved great applications in many fields. However, they pose a serious threat on the environment and human health when they enter into the environment. The SDW-ICOF-LED-IFD-CE system was used to determine fluorescein isothiocyanate (FITC)-labeled sulfadoxine (SDM), sulfaguanidine (SGD) and sulfamonomethoxine sodium (SMM-Na) in environmental water. The detection results obtained by the SDW-ICOF-LED-IFD-CE system were compared to those acquired by the CE with in-capillary optical fiber light-emitting diode-induced fluorescence detection (ICOF-LED-IFD-CE). The limits of detection (LODs) of SDW-ICOF-LED-IFD-CE and ICOF-LED-IFD-CE were 1.0-2.0 nM and 2.5-7.7 nM (S/N = 3), respectively. The intraday (n = 6) and interday (n = 6) precision of migration time and corresponding peak area for both types of CE were all less than 0.86% and 3.68%, respectively. The accuracy of the proposed method was judged by employing standard addition method, and recoveries obtained were in the range of 92.5-102.9%. The results indicated that the sensitivity of the SDW-ICOF-LED-IFD-CE system was improved, and that its reproducibility and accuracy were satisfactory. It was successfully applied to analyze SAs in environmental water.

Lithium metal is the most ideal anode for next‐generation lithium‐ion batteries. However, the formation of lithium dendrites and the continuous consumption of electrolyte during cycling lead to a serious safety problems. Developing stable lithium metal anode with uniform lithium deposition is highly desirable. Herein, a nitrogen plasma strengthening strategy is proposed for copper oxide nanosheet–decorated Cu foil as an advanced current collector, and deep insights into the plasma regulating mechanism are elaborated. The plasma‐treated electrode can maintain a high coulombic efficiency of 99.6% for 500 cycles. The symmetric cell using the lithium‐plated electrode can be cycled for more than 600 h with a low‐voltage hysteresis (23.1 mV), which is much better than those of electrodes without plasma treatment. It is well confirmed that this plasma‐induced nitrogen doping method can provide sufficient active sites for lithium nucleation to enhance the stability of lithium deposition on copper oxide nanosheets decorated on Cu foil and improve the electrical conductivity to greatly reduce the overpotential of the lithium nucleation, which can be extended to other modified current collectors for stable lithium metal anode., A nitrogen plasma strengthening strategy is proposed for copper oxide nanosheet–decorated Cu foil as an advanced current collector. The plasma‐induced nitrogen doping can provide sufficient active sites for lithium nucleation to enhance the stability of lithium deposition. This strategy can be extended to other modified current collectors for stable lithium metal anode.

A promising strategy for trace analysis of hydrogen peroxide (H2O2) in natural water was established based on solid substrate room temperature phosphorimetry. The use of TiO2/SiO2 composite material as a phosphor for H2O2 detection was investigated. TiO2/SiO2 nanoparticle material was manufactured into a test kit for synchronous multilevel sampling test in the water sample reservoir. The proposed TiO2/SiO2 test kit displayed a wide linear response to H2O2 concentrations ranging from 1.0 × 10(-6) to 1.0 × 10(-1) M with a detection limit of 4.6 × 10(-7) M. When the concentration of other species was 100 times of 1.0 × 10(-4) M H2O2, the proposed test kit exhibited good selectivity toward the coexistence of 20 foreign ions. Satisfactory agreement between the proposed kit and spectrophotometric method was obtained, which demonstrated the possibility of its further development into a promising commercial phosphorescence sensor.

Highly efficient electrogenerated chemiluminescence (ECL) of natural chlorophyll a (Chl a) was observed in acetonitrile with 1-butyl-3-methylimidazolium hexafluorophosphate as electrolyte and tri-n-propylamine (TPrA) as a coreactant. The collected ECL spectrum displayed a maximum emission peak at ca. 670 nm, suggesting that the same excited states with the photo-excitation processes were generated. The possible ECL reaction mechanism of this Chl a–TPrA system was discussed and established. ECL intensity of Chl a was proportional to its concentration over the range of 0.1–11 μM, and a high ECL efficiency (Φecl) of 0.86 was calculated using Ru(bpy)32+ as the standard (Φecl = 1). Herein, an important property of natural Chl a was expanded and a new kind of ECL luminophores was developed. Moreover, it is expected that this high ECL efficiency of natural porphyrin complex has great potential to expand its ECL sensing application. Keywords: Electrogenerated chemiluminescence, Chlorophyll a, ECL efficiency, Reaction mechanism, TPrA

Although lithium metal has been considered as the most potential anode for next-generation lithium-based batteries, the uncontrollable growth of lithium dendrites is still a serious challenge for the practical application. Herein, Sn layer with superior lithiophilicity was proposed to decorate copper mesh by electrodeposition as current collector, which could induce the lithium nucleation uniformly and stabilize the process of lithium plating and stripping, leading to dendrite-free lithium deposition behavior and excellent stable cycling performance. It was found that Li–Sn alloy would be formed by the pre-lithiation of Sn layers and its superior lithiophilicity was further proved by density functional theory calculation. As a consequence, the lithium nucleation overpotential of the optimal sample was only 2.8 mV, very close to Au and Ag, and the electrode could maintain a high Coulombic efficiency of 98.6% for 900 cycles. The lithium plated electrode could achieve a long lifespan of 1000 h in the symmetric cell with low-voltage hysteresis of 6.1 mV.

Background: One of the central challenges for cancer therapy is the identification of factors in the tumor microenvironment that increase tumor progression and prevent the immune system from eradicating the tumor. One such factor associated with breast cancer is stromal fibrosis, a histopathologic criterion for invasive cancer and poor survival. Fibrosis is caused by inflammatory factors and remodeling of the extracellular matrix, which results in excessive collagen deposition and an immune tolerant environment. Experimental Procedures: We developed a novel transgenic model representative of HER2/ErbB2+ breast cancer, termed NeuT/ATTAC, in which partial ablation of mammary fat resulted in its replacement with fibrotic tissue. NeuT/ATTAC mice were administered a diet supplemented with 0.04% DMHCA, a desmosterol-like pan agonist of the liver X receptor (LXR). Collagen deposition resulting from fibrosis was assessed by second harmonic generation (SHG) fluorescence microscopy and histological staining, immune cell subsets were analyzed by fluorescence-activated cell sorting and biomarkers of fibrosis, proliferation and immune tolerance were determined by IHC. Findings: Administration of DMHCA to NeuT/ATTAC mice beginning at two months of age reduced tumorigenesis, tumor multiplicity and suppressed fibrosis as shown by loss of collagen, fibroblast activation protein (FAP) and α-smooth muscle actin (SMA). These changes were accompanied by a marked reduction in the percentage of MDSC, and an increase in CD8+ effector T cells and PD1+/Foxp3+ CD4 T cells. Conclusion: Reduction of fibrosis, tumorigenesis and immune tolerance by DMHCA suggests that this LXR agonist may be useful for reducing tumor-associated fibrosis and in combination with immune checkpoint inhibitors that target PD1+ Treg cells for moderating immune tolerance. Unlike non-steroidal LXR agonists, DMHCA does not increase serum triglycerides or produce hepatic steatosis, and may therefore be a good candidate for clinical studies. Supported by a Sher Award, 1P30CA051008 from the NCI, NIH, to the Lombardi Comprehensive Cancer Center, and R01 HL133545 and R01 DK116567 from the NIH to M.L. Citation Format: Robert I. Glazer, Gao Sheng, Hongyan Yuan, Suman Ranjit, Jin Lu, Xun Lu, Moshe Levi. LXR agonist N,N-dimethyl-3-β-hydroxy-cholenamide, DMHCA, reduces ErbB2-dependent tumorigenesis and immune tolerance in a conditional model of mammary fibrosis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 394.

Cell migration is a fundamental biological process involved in many physiological and pathological processes. To understand how cell migration works at the whole cell level, biomechanical and biochemical models have been developed but were mainly independent of each other. In this work, we developed a mechanobiochemical model for cell migration at the whole-cell scale. In the model, mechanics of cytoskeleton contraction generates distributed forces for the cell to sense the mechanical properties of itself and its microenvironment. The mechanosensing is coupled with the signaling network of reaction–diffusion of biomolecules in the cell. The computational results show that the model can simulate cell polarization (head-to-tail formation) and shape-dependent localization of the protrusion signal. Furthermore, this dynamic model of cell migration can recapitulate durotaxis in silicon and simulate cellular morphogenesis.

Mucin 1 (MUC1), being an oncogene, is an attractive target in tumor immunotherapy. Maltose binding protein (MBP) is a potent built-in adjuvant to enhance protein immunogenicity. Thus, a recombinant MUC1 and MBP antitumor vaccine (M-M) was constructed in our laboratory. To enhance the antitumor immune activity of M-M, CpG oligodeoxynucleotides 1826 (CpG 1826), a toll-like receptor-9 agonist, was examined in this study as an adjuvant. The combination of M-M and CpG 1826 significantly inhibited MUC1-expressing B16 cell growth and prolonged the survival of tumor-bearing mice. It induced MUC1-specific antibodies and Th1 immune responses, as well as the Cytotoxic T Lymphocytes (CTL) cytotoxicity in vivo. Further studies showed that it promoted the maturation and activation of the dendritic cell (DC) and skewed towards Th1 phenotype in vitro. Thus, our study revealed that CpG 1826 is an efficient adjuvant, laying a foundation for further M-M clinical research.

Mucin 1 (MUC1) is an oncogene that has a crucial role in the pathogenesis and progression of the majority of epithelial malignant tumors. Our previous study demonstrated that MUC1 gene silencing inhibited the growth of SMMC-7721 cells in vitro and in vivo, however, whether this growth inhibition is associated with apoptotic cell death remains to be elucidated. In the present study, it was found that MUC1 gene silencing not only resulted in the inhibition of SMMC-7721 cell growth, determined using a clone formation assay in vitro and a tumor xenograft mouse model with an in vivo imaging system, but also induced apoptotic alterations in SMMC-7721 cells, determined using Hoechst 33342 staining, flow cytometry with an Annexin V-PE staining and a DNA ladder assay. Further investigation using western blotting revealed that cytochrome c was released from the mitochondria into the cytoplasm, and caspase-8 and caspase-9 were activated in MUC1 gene-silenced SMMC-7721 cells. The pro-apoptotic protein Bcl-2-associated X protein (Bax) and the tumor suppressor p53 were increased, while the anti-apoptotic protein B-cell lymphoma 2 was decreased in MUC1 gene-silenced cells. In addition, results from the co-immunoprecipitation experiments demonstrated that the MUC1 cytoplasmic tail can bind directly to Bax or caspase-8 and these interactions were reduced upon MUC1 gene silencing in SMMC-7721 cells. The above results indicate that MUC1 gene silencing induces growth inhibition in SMMC-7721 cells through Bax-mediated mitochondrial and caspase-8-mediated death receptor apoptotic pathways.

This work reported the synthesis of cobalt hydroxide using different cobalt precursors via a simple, operable and rapid microwave-assisted method and their electrochemical capacitors application. The experimental results demonstrated that cobalt precursors remarkably impacted on not only microscopic dimensions and morphologies but also crystalline phase. Especially, the loose-packed lamellar α-cobalt hydroxide was synthesized using cobalt sulfate as the precursor. The electrochemical properties of the as-obtained samples were investigated in detail by cyclic voltammetry and galvanostatic charge/discharge tests. The results of electrochemical tests demonstrated that the loose-packed lamellar structure endowed the cobalt hydroxide with a superior specific capacitance of 711.3 F/g in a potential window of 0–0.55 V. In addition, the asymmetric supercapacitor, fabricated by using the obtained cobalt hydroxide as positive electrode material and oxygen-rich porous carbon as negative electrode material, exhibited excellent rate performance. This work held an important guideline value for the development of cobalt-based electrochemical capacitors.

LiNi1/3Co1/3Mn1/3O2 (NCM) is a promising cathode material for lithium-ion battery. In this research, a facile co-precipitation process is employed, during which the mixed solution of NH3·H2O, H2O2 (30% aqueous solution) and LiOH·H2O is added into the nitrate solution. Notably, H2O2 is introduced as the oxidant and dispersant during the co-precipitation process to oxidize the metal ions and decrease the agglomeration of the precursor by giving out O2, and then improves the specific capacity, stability and energy density of NCM. Additionally, O3 is employed to further oxidize NCM to enhance the stability during the calcination process. The obtained NCM material with single crystal structure exhibits a high initial discharge specific capacity of 208.9 mAh g−1 at 0.1 C (1 C = 280 mA g−1), an excellent cycle stability with high retained capacity of 176.3 mAh g−1 after 50 cycles, and a high initial discharge specific capacities of 150.6 mAh g−1 at 5 C even at a high cutoff potential (4.6 V).

Hydrogen (H2) generated from water splitting is deemed as the ideal replacement for conventional sources of energy. Catalysts play a valuable role in water splitting, especially the oxygen evolution reaction (OER). Here, we report a Fe-doped Co3V2O8 nanoparticle catalyst (iron-rich V–Co–Fe), which possesses outstanding OER catalytic activity with ηj = 10 mA cm−2 = 307 mV, and a low Tafel slope of 36 mV dec−1, benefiting from a large degree of amorphization, a rich porous structure and a high specific surface area (about 232.1 m2 g−1). More remarkably, the catalytic performance of the V–Co–Fe catalyst is markedly superior to commercial ruthenium oxide. In addition, the durability of the V–Co–Fe catalyst is fine. The current density collapses by less than 3 percent at 1.55 V vs. RHE after 11 h in comparison to the initial value. Moreover, this work reveals that the V–Co–Fe catalyst displays an excellent performance in both OER catalytic activity and stability, and may have the potential to be the ideal substitute for noble metal-based catalysts for water splitting to obtain affordable clean energy.

A novel improved molten-salt synthesis was employed to synthesize the Ni(OH)2/NiOOH composite by using a mixed precursor of nickel nitrate and nickel acetate. Here, the molted salt was used as reactant for the first time, rather than a reaction medium in the conventional molten salt method. The synthesized Ni(OH)2/NiOOH composite possesses loose lamellar structure, which could facilitate the transport of electrolyte ions during the rapid charge/discharge process. The capacitive properties of the composite were evaluated by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy techniques in 6 M KOH aqueous electrolyte. Electrochemical results shown that the Ni(OH)2/NiOOH composite which obtained with this nickel acetate assisted route was endowed with high pseudocapacitance performance of 1425 F g−1 at 2 A g−1. The material exhibited moderate rate capability, high energy density of 59.85 W h kg−1 and high power density of 0.55 kW kg−1.

The mechanisms underlying the spatial organization of self-assembled myofibrils in cardiac tissues remain incompletely understood. By modeling cells as elastic solids under active cytoskeletal contraction, we found a good correlation between the predicted maximal principal stress directions and the in vitro myofibril orientations in individual cardiomyocytes. This implies that actomyosin fibers tend to assemble along the maximal tensile stress (MTS) directions. By considering the dynamics of focal adhesion and myofibril formation in the model, we showed that different patterns of myofibril organizations in mature versus immature cardiomyocytes can be explained as the consequence of the different levels of force-dependent remodeling of focal adhesions. Further, we applied the mechanics model to cell pairs and showed that the myofibril organizations can be regulated by a combination of multiple factors including cell shape, cell–substrate adhesions, and cell–cell adhesions. This mechanics model can guide the rational design in cardiac tissue engineering where recapitulating in vivo myofibril organizations is crucial to the contractile function of the heart.

An efficient and stable catalyst with fragment-exfoliating structure was prepared by directly ozone treatment of bulk graphitic carbon nitride (g-C3N4). The photocatalytic performances of the as-prepared catalysts were evaluated by degradation of methylene blue (MB) and photocatalytic hydrogen evolution reaction under visible light irradiation. Compared with untreated g-C3N4, the ozone-treated g-C3N4 (OCN) exhibited almost 5 times higher photodegradation activity and 2 times H2 evolution rate. The enhanced photocatalysis capability could be assigned to a narrowed band gap (2.62eV), the increased defects and active sites, and the reduced recombination efficiency of photoinduced carriers in OCN. Furthermore, the photocatalytic mechanism in degradation process of MB was discussed and the hydroxyl radical and superoxide radical have proven to be the predominant active species. It is reasonable to believe that chemical modifying of catalysts through ozone treatment could efficiently regulate its catalytic activity.

To explore the antitumor effect of caffeic acid 3,4-dihydroxy-phenethyl ester (CADPE) on the breast cancer cell lines and illuminate the related mechanism. After treatment with different concentrations of CADPE for 24, 48, and 72 h, cell proliferation ability of the breast cancer cell lines MDA-MB-231 and MDA-MB-435 was analyzed by the MTT. Changes of the cell cycles were evaluated by PI staining. Cell apoptosis was examined by flow cytometry after Annexin V/7AAD double staining. Nuclear morphologic changes were observed under the inverted fluorescence microscope after staining with Hoechst 33342. Mitochondrial membrane potential and reactive oxygen species (ROS) level were estimated by JC-1 and DCFH-DA staining. In addition, the expression level of mitochondrial signaling pathway proteins Bcl-2, Bax, and caspase-3 were evaluated by Western blot. CADPE has the distinct cytotoxic effect to the breast cancer cells, and the effect is dose dependent. It did not change the cell cycles but induced the cell apoptosis of the breast cancer cells. At the same time, after CADPE treatment, the expression levels of caspase-3 and Bax in the breast cancer cells were upregulated and Bcl-2 expression was declined. The ROS level in the breast cancer cells was enhanced, and mitochondrial membrane potential of the cells was downregulated. CADPE has the antitumor functions. It can induce the cell apoptosis through downregulating Bcl-2 expression, enhancing Bax and caspase-3 expression levels, upregulating ROS level and reducing the mitochondrial membrane potential of the breast cancer cells to trigger the mitochondrial signal pathway.

A fast microwave-assisted synthesis method followed by a post-calcining process is used to prepare three-dimensional (3D) nanosphere-like NiCo2O4 nanostructure. The 3D NiCo2O4 nanospheres are constructed by intertwined two-dimensional (2D) ultrathin mesoporous nanosheets. The nanosphere-like NiCo2O4 has a large specific surface area (SSA, 146.5 m2 g−1) and is successfully applied to electro-catalytic oxidation of methanol. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and chronoamperometry (CA) measurements are used to investigate electro-catalytic performance of the as-prepared NiCo2O4. The current density of NiCo2O4/Ni foam (NiCo2O4/NF) electrode in 1 M KOH with 0.5 M methanol is up to 40.9 A g−1. And the current density can be returned to 97% of the original value by replacing new 1 M KOH electrolyte with 0.5 M methanol after a long-term CV cycle (500 cycles). These results show that our prepared NiCo2O4 possesses high electro-catalytic activity and good long-term stability for methanol oxidation. This may be benefit from the unique porous nanosphere-like structure and large SSA.

B-doped g-C3N4 was prepared in the laboratory via heating a mixture of melamine and boric acid. The synthesized material was characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) analysis, which revealed the high specific surface area and large amount of active groups on the surface of B-doped g-C3N4. The sorption of cadmium from aqueous solutions by B-doped g-C3N4 was studied under equilibrium conditions in the concentration range of 0.01˜5.0 mmol/L. The pH of the solution was varied over a range of 2˜6. The sorption of cadmium on the material was determined to be pH-dependent, and the Lagergren-second-order kinetic model was suitable to simulate the sorption process. The maximum sorption capacity from the Langmuir model was determined to be 1.4162 mmol/g (about 159.2 mgCd/g). XPS and FTIR data suggest that cadmium ions were mainly attached to the N-H and O-H groups on the surface of B-doped g-C3N4.

In this study, a novel facile and rapid method to prepare three-dimensional (3D) flower-like CoS hierarchitectures by microwave assisted heating has been developed. The 3D flower-like CoS architectures are constructed by two-dimensional nanopetals intertwined with each other and the formation mechanism are studied. The pseudo-capacitive properties of the CoS material are evaluated by cyclic voltammetry and galvanostatic charge-discharge tests in 6 M KOH solution. A specific capacitance of 586 F g−1 is obtained at a charge-discharge current density of 1 A g−1. The CoS nanostructure exhibits excellent cycling stability and it maintains 91% of its initial specific capacitance after 1000 cycles. It also exhibits excellent rate capability, improved energy density and power density.

Binary metal oxides with three-dimensional (3D) superstructure have been regarded as desirable electrode materials for the supercapacitor due to the combination of the improved electrical conductivity and effective porous structure. 3D hierarchical flower-shaped nickel cobaltite (NiCo2O4) microspheres have been fabricated by a rapid and template-free microwave-assisted heating (MAH) reflux approach followed by pyrolysis of the as-prepared precursors. The flower-shaped NiCo2O4 microspheres, composed of ultrathin nanopetals with thickness of about 15 nm, are endowed with large specific surface area (148.5 m(2) g(-1)) and a narrow pore size distribution (5-10 nm). The as-fabricated porous flower-shaped NiCo2O4 microspheres as electrode materials for supercapacitor exhibited high specific capacitance of 1006 F g(-1) at 1 A g(-1), enhanced rate capability, and excellent electrochemical stability with 93.2% retention after 1000 continuous charge-discharge (CD) cycles even at a high current density of 8 A g(-1). The desirable integrated performance enables it to be a promising electrode material for the electrochemical supercapacitor (EC).