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Cadmium (Cd) accumulation in soil is a serious form of heavy metal pollution affecting environmental safety and human health. In order to clarify the tolerance mechanisms to Cd-contaminated soils under N deposition, changes in plant growth, root architecture and physiological characteristics of Eleocarpus glabripetalus seedlings under combined nitrogen (N) and cadmium (Cd) treatments were determined in this study. The results indicated that Cd-induced negative effects inhibited the growth of E. glabripetalus seedlings through increased underground biomass allocation, and affected transpiration and respiratory processes, resulting in a decreased soluble sugars concentration in leaves and non-structural carbohydrates (NSC) in the roots. Root systems might play a major role in Cd absorption. Cd stress restricted the growth of fine roots (

3D porous carbon from spontaneous merging of the nano-sized ZIF-8 shows continuous conductive network, interconnected porous structure, abundant heteroatoms, and good hydrophilicity, enabling good performance for high-mass-loading supercapacitor.

The large-scale application of lithium sulfur batteries is impeded by their cycling stability and power performance mainly due to the polysulfide shuttle effect and low conductivity of sulfur. Herein, a multifunctional sulfur host of N/S co-doped porous graphene layered matrix (NSPG) is fabricated. High specific surface area of NSPG can guarantee the homogeneous deposition and high utilization of S/Li2S. Moreover, the layered graphene skeleton with abundant crumples can not only construct efficient channels for fast electrolyte ion/electron transfer but also effectively buffer the volume expansion of S during long-time charge/discharge process. DFT calculations verify that the N/S co-doping can promote the redox reaction rate and inhibit the polysulfides shuttle effect through chemical bonding interaction. Benefiting from the above synergistic effects, the NSPG/S electrode exhibits excellent rate performance (646 mAh g−1 at 10C) and outstanding cycle stability (693 mAh g−1 after 500 cycles). Even at a high mass loading of 4.5 mg cm−2, a capacity of 786 mAh g−1 can be retained after 100 cycles. This work might offer a feasible solution for developing sulfur host with multifunctionality and electrocatalytic activity for high-performance lithium sulfur batteries.

Improving both surface and space utilization of active carbon is crucial for compact supercapacitors. Herein, two activated carbons are prepared through homogeneous activation (HAC) and traditional outside-in activation (OIAC). Compared with OIAC with deep and branched porous structure, HAC shows an interconnected porous structure, leading to higher density, better gravimetric and volumetric capacitances, and improved rate performance. The results demonstrate that interconnected porous structure by homogeneous activation promotes high surface and space utilization as well as robust ion transport kinetics of activated carbon for capacitive energy storage.

Hepatocellular carcinoma (HCC) is the most common type of hepatic malignancies with high mortality and poor prognosis. Baicalein, one of the major and bioactive flavonoids isolated from Scutellaria baicalensis Georgi, which is reported to have anti-proliferation effect in varying cancers, including HCC, whose underlying molecular mechanism is still largely unknown. In this study, we found that baicalein significantly inhibited proliferation and colony formation, blocked cell cycle, and promoted apoptosis in HCC cells MHCC-97H and SMMC-7721 in vitro and reduced tumor volume and weight in vivo. Increased microRNA (miR)-3,178 levels and decreased histone deacetylase 10 (HDAC10) expression were found in cells treated with baicalein and in patients' HCC tissues. HDAC10 was identified as a target gene of miR-3,178 by luciferase activity and western blot. Both baicalein treatment and overexpression of miR-3,178 could downregulate HDAC10 protein expression and inactivated AKT, MDM2/p53/Bcl2/Bax and FoxO3α/p27/CDK2/Cyclin E1 signal pathways. Not only that, knockdown of miR-3,178 could partly abolish the effects of baicalein and the restoration of HDAC10 could abated miR-3,178-mediated role in HCC cells. Collectively, baicalein inhibits cell viability, blocks cell cycle, and induces apoptosis in HCC cells by regulating the miR-3,178/HDAC10 pathway. This finding indicated that baicalein might be promising for treatment of HCC.

Although activated carbon has been widely used for supercapacitors, the unsatisfactory volumetric capacitance and rate performance caused by the well-developed porous structure severely hinder its application in minimized and high-power devices. Herein, we develop an electrostatic densification method to prepare large surface area (ca. 3359 m2 g−1) and high density activated carbon materials by using the positively charged chitosan and negatively charged graphene quantum dots (GQDs) as the precursors. The strong molecular electrostatic attraction makes the GQDs embedded activated carbon an improved compaction density of 0.75 g cm−3 than the activated carbon without GQDs (3245 m2 g−1, 0.67 g cm−3) and commercial activated carbon (1600 m2 g−1, 0.45 g cm−3). The highly crystallized GQDs can also improve the electrochemical kinetics by constructing the entire conductive networks. Therefore, the sample shows high capacitances of 341 F g−1/256 F cm−3 at 1 A g−1 and remarkable rate performance with 70% capacitance retention at 100 A g−1 in three-electrode system. Moreover, the outstanding capacitive performance can maintain at the commercial mass loading of 10 mg cm−2, demonstrating great potential for practical application.

Hepatocellular carcinoma (HCC) is the most common type of hepatic malignancies with high mortality and poor prognosis and is the third most common cause of malignancies death worldwide which is more than 700,000 deaths per year. Baicalein, one of the major and bioactive flavonoid isolated from Scutellaria baicalensis Georgi, which is reported to have anti-proliferation effect in varying cancers, including HCC, whose underlying molecular mechanism is still largely unknown. In this study, the results showed that administration of baicalein significantly inhibited proliferation and colony formation, blocked cell cycle arrest at the S phase, and promoted apoptosis in HCC cells MHCC-97H and SMMC-7721 in vitro and reduced HCC tumor volume and weight in vivo. Increased microRNA (miR)‑3178 levels and decreased histone deacetylase 10 (HDAC10) expression were found in cells treated with baicalein and in patients’ HCC tissues. HDAC10 was identified as a target gene of miR‑3178 by luciferase activity and western blot. Both baicalein treatment and overexpression of miR-3178 could down-regulate protein expression of HDAC10 and inactivated AKT, MDM2/p53/Bcl2/Bax and FoxO3α/p27/CDK2/Cyclin E1 signal pathways. Not only that, knockdown of miR‑3178 could partly abolish the effects of baicalein and the restoration of HDAC10 could abated miR-3178-mediated role in HCC cells. Collectively, baicalein inhibited cell viability, blocks cell cycle and induces apoptosis in HCC cells by regulating the miR‑3178/HDAC10 pathway. This finding indicated that baicalein might be promising for treatment of HCC.

Baicalein is a purified flavonoid that exhibits anticancer effects in hepatocellular carcinoma (HCC). However, its underlying molecular mechanisms remain largely unclear. In this study, we found that baicalein inhibited HCC cell growth, induced apoptosis, and blocked cell cycle arrest at the S phase in vitro, as well as reduced HCC tumor volume and weight in vivo. Quantitative reverse transcriptase-PCR (qRT-PCR) results suggested that miR-3663-3p was downregulated in HCC tissues. After baicalein treatment, miR-3663-3p expression was upregulated in HCC cells. Transfection of miR-3663-3p suppressed HCC cell proliferation and colony formation, increased the proportion of apoptotic cells in vitro, and reduced the volume and weight of tumors in vivo. The results of dual-luciferase reporter assay showed that miR-3663-3p could directly bind to the 3'-UTR of SH3GL1. SH3GL1 overexpression partly reduced the growth-inhibiting effect of miR-3663-3p. Both baicalein treatment and miR-3663-3p overexpression downregulated the expression of SH3GL1 and inactivated the Erk1/2, p-NF-κB/p65, and EGFR signaling pathways. Overall, our data suggest that baicalein may act as a novel HCC suppressor, and that the miR-3663-3p/SH3GL1/EGFR/ERK/NF-κB pathway plays a vital role in HCC progression. Thus, baicalein treatment or miR-3663-3p induction may be a promising strategy for HCC therapy.

Objective To study the expression and significance of myeloid-derived suppressor cell (MDSC)-associated chemokines in the spleen of hepatoma H22-bearing mice. Methods The percentage of splenic MDSCs was examined by flow cytometry. Splenic MDSCs were sorted using flow cytometry and co-cultured with activated splenocytes, and then the level of IFN-γ in the supernatant of co-cultured cells was assayed by ELISA. The murine orthotopic hepatoma model was established. The differential cytokine expression in the spleens of normal and tumor-bearing mice was assayed by protein chip, and splenic MDSC-associated chemokines were verified using ELISA. The chemokine receptors on splenic MDSCs were also detected by flow cytometry. Results The percentage of splenic MDSCs was markedly raised in the tumor-bearing mice, and splenic MDSCs exhibited immune-inhibitory function. Ten up-regulated cytokines and nine down-regulated ones were found out using protein chip. Among the up-regulated cytokines, 5 cytokines were chemokines, namely B lymphocyte chemoattractant (BLC), chemokine (C-X-C motif) ligand 16 (CXCL16), macrophage/monocyte chemotactic protein-5 (MCP-5), macrophage inflammatory protein 1γ (MIP-1γ) and MIP-2. The level of splenic MDSC-associated chemokine MIP-1γ significantly increased in the spleen of tumor-bearing mice, and its receptor CCR1 was also expressed on the cell surface of splenic MDSCs. Conclusion Splenic MDSC-associated chemokine MIP-1γ and its receptor CCR1 were obtained by protein chip, and they might be associated with the accumulation of splenic MDSCs in hepatoma H22-bearing mice.

A novel modified separator was synthesized with an ultraviolet irradiated polypropylene (PP) membrane and acrylonitrile monomers by a solution grafting reaction. It was demonstrated that polyacrylonitrile (PAN) was grafted on the PP separator surface by analyzing the results of FESEM, ATR–FTIR and XPS. The thermostability and wettability of the PAN-grafted PP (PP-g-PAN) separator were enhanced. Then, Li–S batteries were assembled using the modified separators. The cycling and rate capacity performance is improved clearly because of the higher liquid uptake, smaller porous size, better polysulfides absorption effect and interfacial affinity of the grafted separator. The modified separator can hinder the movement of Li2Sx effectively to prevent the shuttle effect of a Li–S battery. Therefore, this efficient method has great potential to be applied to the modification of other kinds of polymer membranes.

Onion-derived nitrogen, sulfur self-doped nanoporous carbon spheres (NSC) as efficient metal-free electrocatalyst were synthesized via a facile hydrothermal and subsequent pyrolysis process. The typical NSC with a high BET specific surface area of 1558 m 2 g −1 , contains 6.23 at.% N and 0.36 at.% S, and possesses high concentration of pyridinic and graphitic nitrogen species. Experimentally, the best performance was the NSC-A2 which showed excellent catalytic activity to oxygen reduction reaction via a 4 electron mechanism with an onset potential of 0.88 V (vs. RHE), and a superior stability comparable to commercial Pt/C catalyst. The high electrocatalytic activity is attributed to not only the synergistic effect of N and S dual doping in carbon and the sufficient active sites, but also its high BET specific surface area and suitable microporous structure. The results demonstrate that it is a simple and scalable approach for preparing efficient and low-cost carbon-based electrocatalysts for oxygen reduction reaction.

Developing catalysts with high bi-functional electrocatalytic activity for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is essential for the fuel cells and metal-air batteries because of the sluggish kinetics of oxygen electrochemical reaction. Herein, we prepared a porous and well dispersed spinel MnCo 2 O 4 (MCO) catalyst through a facile solvothermal method followed by a calcination process. CH 3 COONH 4 used in solvothermal process played an important role in control of the size and morphology of MCO. The as-prepared MCO submicrospheres feature a porous structure and a high specific surface area. Tested by the rotating ring disk electrode (RRDE) technique, the sample MCO-10 and MCO-5 shows best catalytic towards ORR and OER, respectively. In particular, MCO-10 exhibits a high diffusion limiting current density (5 mA cm −2 ) and a better stability comparable to commercial Pt/C (20 wt% Pt on carbon) catalyst.

Lotus-root-like MnO/C mesoscale hybrids, featuring nanometer-sized monodisperse metal oxide particles uniformly embedded in a porous carbon matrix, were in situ synthesized by a facile and scalable method: poly(vinyl alcohol)-assisted aqueous precipitation followed by thermal decomposition of the precursors. The resulting hierarchical-structured MnO/C hybrids showed a desirable capacity, as well as superior cycling durability and rate capability. These performances can be ascribed to its particular structure: The cavity of the lotus root and the voids between manganese oxide and carbon are sufficient mechanical buffers to avoid agglomeration and pulverization, and the conductive pathway of well-interconnected carbon “walls” favor fast electron and Li-ion transport during electrochemical cycling.

A flexible elastic N-doped carbon foam (NCF) has been successfully synthesized in situ via direct carbonization/pyrolysis of polyurethane foam, which is a facile, cost-effective and environmentally friendly method. Due to its uniform three-dimensional connected structure, its reasonable composition with N doping and its high electronic conductivity, the NCF can function as both a three-dimensional current collector and a carbon interlayer for lithium sulfur batteries. As a typical model, cathodes consisting of NCF and CNT/S were prepared. The resulting batteries deliver a large reversible capacity of 1124 mA h g−1 at 0.5C and retain a high specific capacity of 902.8 mA h g−1 after 100 cycles, with a coulombic efficiency of 98.6% throughout the cycles. Furthermore, a discharge capacity of 691.8 mA h g−1 is still attainable when the rate is increased to 2.0C. The excellent cycling performance and rate capability are contributed to the uniform flexible elastic, conductive 3D framework and good porosity, and may have great significance for large-scale commercial applications of Li–S batteries.

Lithium–sulfur (Li–S) batteries with an effective adsorbing interlayer, high capacity and long cycle life have been fabricated using a simple method by placing an interlayer between the sulfur cathode and the separator. The interlayer with optimized porosity, electrolyte uptake and electrical conductivity can facilitate the use of pure sulfur (with a sulfur content of 70%) as a highly reversible cathode, which was made of carbonized non-woven fabrics (Mind Act Upon Mind™ Skincare Wipes) modified with Ketjenblack. A high capacity of 1486 mA h g−1 at a rate of 0.1C (1C = 1675 mA g−1) in the first cycle was obtained, and the reversible capacity remains high, up to 858 mA h g−1, even after 100 cycles.

Dark energy phenomena has inspired lots of investigations on the cosmological constant problems. In order to understand its origin and properties as well as its impacts on universe's evolutions, there are many approaches to modify the well-known General Relativity, such as the Weyl-Lyra Geometry. In the well studied cosmology model within Lyra geometry, there is a problem that the first law of thermodynamics is violated. To unravel this issue, if we use the effective density and pressure in the Lyra cosmology model to preserve the first law of thermodynamics in the cosmos, the former 1-form $(\beta,0,0,0)$ cannot give a proper vacuum behavior. In this paper, the auxiliary 1-form is modified to overcome this difficulty. It can be shown that the complex terms in the field equation derived from the regime of Lyra Geometric$ \frac{3}{2}{\phi}^{\mu}{\phi}_{\nu}-\frac{3}{4}{\delta}^{\mu}_{\nu}{\phi}^{\alpha}{\phi}_{\alpha}$with our new 1-form could behave just as the cosmological constant. This work can be regarded as a new exploration on a possible origin of the cosmological constant from a Lyra cosmology model., Comment: 8 pages. Accepted for publication in IJTP

The interface between metal oxide and conductive carbon material is important for rate performance and cycling stability of the electrode materials for lithium-ion batteries. Herein, we present a simple strategy for tightly anchoring ultra-small NiO nanoparticles on nitrogen-doped flower-like carbon scaffold through strong Ni–O–C and Ni–C dual chemical bonds. Benefiting from the robust interfacial interaction and high surface compatibility, the overall conductivity and structural robustness of the NiO/Ni/nitrogen-doped carbon complex improve significantly. Moreover, the unique open-porous structure which consists of interconnected carbon sheets provides sufficient electron/ion transport paths. Therefore, the composite reveals high capacity as high as 1025 mAh g−1 at 0.1 A g−1, superior rate capability (468 mAh g−1 at 2 A g−1) and remarkable cyclic stability (662 mAh g−1 retention after 500 cycles at 0.5 A g−1).

MnO/MWCNT composites were synthesized through a vacuum solution infiltration method and a subsequent low temperature calcination process. The MnO/MWCNT composites with an empty space among the nanoparticles or inside the Multiwalled carbon nanotubes (MWCNTs), which can act as a buffer matrix to release the volume expansion, effectively solved the existing issues of active nanoparticle dissolution and aggregation during the lithium ion insertion/extraction. The MWCNTs in the composites can also improve the conductivity of electrode. Electrochemical tests show that the composites exhibit excellent cycling property and good rate performance.