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Three novel three-dimensional orthorhombic carbon phases are proposed based on first-principles calculations in this work. These phases possess dynamic stability and mechanical stability and are theoretically more favorable in energy compared to most other carbon allotropes. The hardness levels of oP-C16, oP-C20, and oP-C24 are 47.5, 49.6, and 55.3 GPa, respectively, which are greater than those of T10, T18, and O12 carbon. In addition, although oP-C16, oP-C20, and oP-C24 are metals, their ideal shear strengths are also greater than those of common metals such as Cu, Fe, and Al. Due to p y electrons crossing the Fermi level, oP-C16, oP-C20, and oP-C24 show metallicity, and their charge densities of the band decomposition suggest that all the conductive directions of oP-C16, oP-C20, and oP-C24 are exhibited along the a- and b-axis, similar to C5.

Autophagy of vascular endothelial cells (VECs) plays an important role in maintaining vascular homeostasis. Lipid droplets (LDs) are organelles that can be formed in response to various stimuli, including excessive lipid or various stresses. LDs sequester toxic lipids, thereby preventing lipotoxic cell damage and have a complex relationship with autophagy. In the previous study, we identified a novel Grp94 inhibitor HCP1 inhibited apoptosis in VECs. Here we found that HCP1 targeted LDs and promoted the accumulation of LDs in VECs. Our results showed that HCP1 upregulated the protein levels of autophagy-related proteins. We demonstrated that HCP1 upregulated the number of LDs and suppressed autophagy by inhibiting Grp94. Therefore, we provided HCP1 as a new VECs autophagy inhibitor targeting LDs, which might be a potential compound in the treatment of VECs autophagy related vascular diseases.

A new tetragonal carbon allotrope (named T-C64) is predicted by swarm structural searches combined with first principles calculation. It contains 64 carbon atoms in a Tetragonal unit cell with I41/amd symmetry and exhibits distinct topologies including C28 cages. This new carbon phase has an sp2-sp3 network with calculated hardness of 68.2 GPa. In order to examine the stability of T-C64 under ambient pressure, we calculated the properties of elastic constant and phonon spectrum. In addition, by calculating the electronic properties of the crystal, it is concluded that T-C64 is an indirect band gap semiconductor with a band gap of 2.23 eV.

High-throughput first principles calculations for 109 carbon allotropes were performed. The elastic constants and phonon calculations suggest that these new structures are mechanically and dynamically stable at ambient pressure. Seven direct band gap semiconductor carbon allotropes were uncovered. The Vickers hardness of all seven structures exceeds 40 GPa, indicating that these allotropes are potential superhard materials.

Refractory tungsten silicides have been identified as typical high-temperature structural materials with excellent mechanical and thermal properties in various industrial applications. Here, we show the first extensive crystal structures search of W–Si system over a wide range of stoichiometries at ambient condition, using first-principles swarm intelligence structure search methods. Besides the well-known W5Si3 and WSi2, three novel and unexpected stoichiometries of W2Si, WSi, and W3Si4 with tetragonal ground-state structures were firstly uncovered and suggested to be experimentally synthesizable according to the convex hull calculations. It is found that the high silicon content benefits the formation of the puckered double W–Si zigzag covalent chains in WmSin, resulting in the enhanced resistance to shear deformation related to the macroscopic hardness. Results on the ideal tensile and shear strengths calculations indicated that the failure modes in the studied WmSin are mainly dominated by the shear type along the (110) [ 1 1 ‾ 0 ] directions. Further analysis of atomic shear deformation demonstrates that the collapse of Si–W building blocks is responsible for the lattice stability and achievable mechanical strength of WmSin.

Vitamin B12 is a crucial fine chemical that is widely used in the pharmaceutical, food and chemical industries, and its production solely dependents on microbial fermentation. We previously constructed an artificial vitamin B12 biosynthesis pathway in Escherichia coli, but the yield of the engineered strains was low. Here, we removed metabolic bottlenecks of the vitamin B12 biosynthesis pathway in engineered E. coli strains. After screening cobB genes from different sources, optimizing the expression of cobN and customizing the ribosome binding sites of cobS and cobT, the vitamin B12 yield increased to 152.29 μg/g dry cell weight (DCW). Optimization of the downstream module, which converts co(II)byrinic acid a,c-diamide into adenosylcobinamide phosphate, elevated the vitamin B12 yield to 249.04 μg/g DCW. A comparison of a variety of equivalent components indicated that glucose and corn steep liquor are optimal carbon and nitrogen sources, respectively. Finally, an orthogonal array design was applied to determine the optimal concentrations of glucose and nitrogen sources including corn steep liquor and yeast extract, through which a vitamin B12 yield of 530.29 μg/g DCW was obtained. The metabolic modifications and optimization of fermentation conditions achieved in this study offer a basis for further improving vitamin B12 production in E. coli and will hopefully accelerate its industrial application.

Radiation protection on male testis is an important task for ionizing radiation‐related workers or people who receive radiotherapy for tumours near the testicle. In recent years, Toll‐like receptors (TLRs), especially TLR4, have been widely studied as a radiation protection target. In this study, we detected that a low‐toxicity TLR4 agonist monophosphoryl lipid A (MPLA) produced obvious radiation protection effects on mice testis. We found that MPLA effectively alleviated testis structure damage and cell apoptosis induced by ionizing radiation (IR). However, as the expression abundance differs a lot in distinct cells and tissues, MPLA seemed not to directly activate TLR4 singling pathway in mice testis. Here, we demonstrated a brand new mechanism for MPLA producing radiation protection effects on testis. We observed a significant activation of TLR4 pathway in macrophages after MPLA stimulation and identified significant changes in macrophage‐derived exosomes protein expression. We proved that after MPLA treatment, macrophage‐derived exosomes played an important role in testis radiation protection, and specially, G‐CSF and MIP‐2 in exosomes are the core molecules in this protection effect.

Energy is a major driving force for the economic development. Due to the scarcity of fossil fuels and negative impact on the environment, it is important to develop renewable and sustainable energy sources for humankind. Microalgae as the primary feedstock for biodiesel has shown great application potential. However, lipid yield from microalgae is limited by the upstream cost, which restrain the realization of large-scale biofuel production. The modification of lipid-rich microalgae cell has become the focus over the last few decades to improve the lipid content and productivity of microalgae. Carbon is a vital nutrient that regulates the growth and metabolism of microalgae. Different carbon sources are assimilated by microalgae cells via different pathways. Inorganic carbon sources are mainly used through the CO2-concentrating mechanisms (CCMs), while organic carbon sources are absorbed by microalgae mainly through the Pentose Phosphate (PPP) Pathway and the Embden-Meyerhof-Pranas (EMP) pathway. Therefore, the addition of carbon source has a significant impact on the production of microalgae biomass and lipid accumulation. In this paper, mechanisms of lipid synthesis and carbon uptake of microalgae were introduced, and the effects of different carbon conditions (types, concentrations, and addition methods) on lipid accumulation in microalgal biomass production and biodiesel production were comprehensively discussed. This review also highlights the recent advances in microalgae lipid cultivation with large-scale commercialization and the development prospects of biodiesel production. Current challenges and constructive suggestions are proposed on cost-benefit concerns in large-scale production of microalgae biodiesel.

Background Recombinant human calcineurin B subunit (rhCNB) has been shown to be an immune‐stimulatory protein promoting cytokine production and inducing phenotypic maturation of Dendritic cells (DCs). In vivo, it has good antitumor efficacy, and has potential as an antitumor drug. Exogenous rhCNB was found to be internalized into tumor cells via the Toll‐like receptor 4 (TLR4) complex, but it was not known whether its immuno‐modulatory and antitumor functions involved entry by this same route. Methods The production and secretion of the cytokines and chemokines in innate immune cells induced by rhCNB were determined by ELISA, and the expression of CD40, CD80, CD86, and MHCII was analyzed by FACs. Experimental Lewis lung cancer (LLC) model was prepared in C57 BL/6 wild‐type (WT) mice, TLR4−/− mice or their littermates by the inoculation of LLCs in their right armpit, and then administrated daily intraperitoneal injections (0.2 mL) of normal saline, rhCNB 20 mg/kg, and rhCNB 40 mg/kg, respectively. Results Recombinant human calcineurin B subunit promoted the production of antitumor cytokines by innate immune cells, and culture supernatants of rhCNB‐stimulated immune cells induced apoptosis of LLCs. In addition, rhCNB up‐regulated CD40, CD80, CD86, and MHCII expression in macrophages and DCs in TLR4+ cells but failed to do so in TLR4 deficient cells. rhCNB also induced the formation of CD4+ and CD8+T cells in splenocytes from WT mice, but not from TLR4‐deficient littermates. Intraperitoneal administration of WT C57BL/6 mice with rhCNB resulted in a 50% reduction in LLC tumor growth, but failed to inhibit tumor growth in TLR4−/− littermates. Conclusions The in vivo antitumor and immunomodulatory effects of rhCNB are mediated by the TLR4. This conclusion is important for the further understanding and development of rhCNB as an antitumor drug.

Transition metal nitrides have been widely used in many scientific and technical areas because of their unique physical and mechanical properties. We report two new nitrogen-rich transition metal nitrides, MoN6 and ReN6, by crystal structure searching technique. Under high pressure, MoN6 will undergo phase transition (from R-3m to Pm-3 phase) at 54 GPa, and ReN6 always keep the R-3m phase in the pressure range from 50 to 100 GPa. There are benzene-like six-membered “N6” rings with nitrogen single bonds in the R-3m phase structures, indicating that MoN6 and ReN6 are expected to be the high-energy-density materials.

Under the first-principles framework, this paper used the CASTEP program to theoretically calculate TiN, TiC, and its intermediate compounds and therefore obtain a theoretical basis for their application. In this paper, the N atoms in the NaCl-type unit cell of TiN were replaced, and the atoms of TiN1-xCx (x = 0.25, 0.5, and 0.75) were constructed by replacing N with C atoms. The unit cell structure of the ternary compound TiN1-xCx (x = 0.25, 0.5, and 0.75) was constructed by replacing N with C atoms. In a subsequent step, these compounds were geometrically optimized and their properties were calculated. These compounds were subsequently subjected to geometric optimization to calculate their properties. By analyzing the electronic structure of the materials, it was found that TiN1-xCx exhibited metallic properties. In addition, this paper focused on the optical properties of TiN1-xCx ternary compounds under different compositions including absorption, reflectivity, refractive index, and photoconductivity. The accuracy and reliability of the theoretical results presented herein were confirmed by comparing current theoretical results with existing experimental or theoretical results.

Titanium pernitride (TiN2) with CuAl2-type structure (I4/mcm, Z = 4), the first reported member to the family of early transition metal pernitride was recently synthesized via direct chemical reactions between titanium mononitride and nitrogen molecules at 73 GPa and 2400 K. Using an unbiased structure searching method combined with first principles calculations, we here have fully investigated the energy landscape of MN2 (M = Ti, Zr, and Hf) at high pressure up to 100 GPa and suggested that the synthesized I4/mcm structure is a metastable form for TiN2 at ambient conditions. A novel tetragonal I4/mmm (Z = 4) structure composed of the MN6 octahedrons connected by peculiar double N N bonded dimers, was identified as the universal thermodynamic ground-state structure for three MN2. Under high pressure, the I4/mmm structure undergoes a first-order phase transition to the discovered I4/mcm structure with a large volume drop, accompanying the increase of coordination and oxidation number of metal M atoms in MN2. The configuration of M+2 [N2]−2 for MN2 in the I4/mmm structure was demonstrated by electronic structure and chemical bonding analyses. The mechanical properties including elastic parameters and elastic anisotropy behaviors of MN2 within I4/mmm structure were systematically studied. Results on the elastic anisotropy and ideal tensile strengths indicate that the (001) planes may be viewed as their cleavage planes.

Six new silicon phases with direct band gaps were found through silicon atomic substitution of carbon in the known carbon structures via high-throughput calculations. The six newly discovered Si phases are in the space groups of Im3[combining macron]m, C2/c, I4/mcm, I4/mmm, P21/m, and P4/mbm, respectively. Their crystal structures, stabilities, mechanical properties, elastic anisotropy, and electronic and optical properties were systematically studied using first-principles density functional theory calculations. All the new phases were proved to be thermodynamically and mechanically stable at ambient pressure. The direct band gap values in the range of 0.658-1.470 eV and the excellent optoelectronic properties of these six Si allotropes suggest that they are promising photovoltaic materials compared to diamond silicon.

As transition metal silicides have been successfully synthesized, the study of the combination of transition metal and silicon is another effective way to investigate the properties of silicide. We recover novel structures of two silicides: MSi (M = Tc, Re). The structures phase are ɛ − F e S i phase (P213) and CsCl phase (Pm3m). Using the Cambridge Serial Total Energy Package (CASTEP) code, we researched the mechanical, electronic and optical properties of MSi (M = Tc, Re) under 0 GPa and 100 GPa. It is found that each structure is dynamically and mechanically stable at 0 GPa, and the Vickers hardness values show that all of them belong to soft materials. Besides, both the P213-MSi and Pm3m-MSi have metallic characters under 0 GPa and 100 GPa. For the reflectivity in the optical properties, it can be observed that the atom and pressure have obvious influence on the reflectivity of Pm3m-MSi, while only the pressure has obvious influence on the reflectivity of P213-MSi. We hope our work will provide some help to the experimental work on the technologically material.

Based on structure prediction method, the machine learning method is used instead of the density functional theory (DFT) method to predict the material properties, thereby accelerating the material search process. In this paper, we established a data set of carbon materials by high-throughput calculation with available carbon structures obtained from the Samara Carbon Allotrope Database. We then trained a machine learning (ML) model that specifically predicts the elastic modulus (bulk modulus, shear modulus, and the Young’s modulus) and confirmed that the accuracy is better than that of AFLOW-ML in predicting the elastic modulus of a carbon allotrope. We further combined our ML model with the CALYPSO code to search for new carbon structures with a high Young’s modulus. A new carbon allotrope not included in the Samara Carbon Allotrope Database, named Cmcm-C24, which exhibits a hardness greater than 80 GPa, was firstly revealed. The Cmcm-C24 phase was identified as a semiconductor with a direct bandgap. The structural stability, elastic modulus, and electronic properties of the new carbon allotrope were systematically studied, and the obtained results demonstrate the feasibility of ML methods accelerating the material search process.

The calcineurin/nuclear factor of activated T cell (CN/NFAT) signaling pathway plays a critical role in the immune response. Therefore, inhibition of the CN/NFAT pathway is an important target for inflammatory disease. The conserved PXIXIT and LXVP motifs of CN substrates and targeting proteins have been recognized. Based on the affinity ability and inhibitory effect of these docking sequences on CN, we designed a bioactive peptide (named pep3) against the CN/NFAT interaction, which has two binding sites derived from the RCAN1-PXIXIT motif and the NFATc1-LXVP motif. The shortest linker between the two binding sites in pep3 is derived from A238L, a physiological binding partner of CN. Microscale thermophoresis revealed that pep3 has two docking sites on CN. Pep3 also has the most potent inhibitory effect on CN. It is suggested that pep3 contains an NFATc1-LXVP–substrate recognition motif and RCAN1-PXIXIT–mediated anchoring to CN. Expression of this peptide significantly suppresses CN/NFAT signaling. Cell-permeable 11-arginine–modified pep3 (11R-pep3) blocks the NFAT downstream signaling pathway. Intranasal administration of the 11R-pep3 peptide inhibits airway inflammation in an ovalbumin-induced asthma model. Our results suggest that pep3 is promising as an immunosuppressive agent and can be used in topical remedies.

Silicon is a preferred material in solar cells, and most of silicon allotropes have an indirect band gap. Therefore, it is important to find new direct band gap silicon. In the present work, a new direct band gap silicon allotrope of o-Si32 is discovered. The elastic constants, elastic anisotropy, phonon spectra, and electronic structure of o-Si32 are obtained using first-principles calculations. The results show that o-Si32 is mechanically and dynamically stable and is a direct semiconductor material with a band gap of 1.261 eV.

Searching for superhard metallic carbon materials has always been an enduring topic in scientific research. In this work, based on first-principles calculations combined with RG2 method, three new sp2–sp3 hybridized superhard metallic carbon phases were proposed, namely, Fddd-C96, Ccca-C32, and Ibam-C48. The structural, mechanical, and electronic properties of these phases are systematically studied. The results show that they are dynamically, thermally, and mechanically stable. The hardness of Fddd-C96, Ccca-C32, and Ibam-C48 are 77, 69, and 43 GPa, respectively. Electronic properties show that all three materials are metallic, the origin of metallicity mainly comes from sp2 hybridization. To compare the properties of carbon materials with high superhardness and low energy, a P parameter was defined. We find that only two carbon allotropes in the well-known Samara Carbon Allotrope Database have higher P parameters than Fddd-C96. The method of P parameter can quickly screen out materials that meet expectations from a large amount of data based on the characteristics of the materials. These three structures are expected to become candidate materials for high-pressure electronic devices.

A new metallic superhard carbon allotrope C5 with five carbon atoms per unit cell is theoretically predicted to be stable at ambient pressure through first-principles calculations combined with unbiased swarm structure searching techniques. This novel carbon allotrope consisting of a mixture of sp2 and sp3 carbon network exhibits excellent mechanical properties with claimed hardness of 58.5 GPa. Results from our calculated strain-stress relationship reveals that the failure mode of crystal lattice for C5 is dominated by shear type in the (010)[101] direction with shear stress magnitude of 74.3 GPa. The calculated electronic band structure of C5 suggests its metallic nature. Detailed analyses of band decomposed charge density show that the metallic nature is contributed by the sp2 carbon atoms, which form conducting pathways along the a- and b-axes.

Isocitrate dehydrogenase kinase/phosphatase (AceK) is a bifunctional enzyme with both kinase and phosphatase activities that are activated by Mg2+. We have studied the interactions of Mn2+and Mg2+ with AceK using isothermal titration calorimetry (ITC) combined with molecular docking simulations and show for the first time that Mn2+ also activates the enzyme activities. However, Mn2+ and Mg2+ exert their effects by different mechanisms. Although they have similar binding constants (of 1.11 × 105 and 0.98 × 105 M−1, respectively) for AceK and induce conformational changes of the enzyme, they do not compete for the same binding site. Instead Mn2+ appears to bind to the regulatory domain of AceK, and its effect is transmitted to the active site of the enzyme by the conformational change that it induces. The information in this study should be very useful for understanding the molecular mechanism underlying the interaction between AceK and metal ions, especially Mn2+ and Mg2+.

Carbon is known to form a number of allotropes due to its ability to exist in different hybridizations. Here, based on first-principles calculations combined with crystal structure searching method, a new hexagonal carbon allotrope named h-C63 was proposed. The calculated elastic constants and phonon calculations confirm that h-C63 is dynamically and mechanically stable. We show that h-C63 is a potential superhard material with the hardness of 58.8 GPa, and electronic structure calculations show that this h-C63 is metallic. Keywords: Carbon, Superhard material, First-principles calculations

The structural, mechanical, electronic properties and stability of body-centered-tetragonal C8 (Bct-C8) were determined by using the first-principles calculations. Bct-C8 is identified to be mechanically and dynamically stable at a pressure range from 0 to 100 GPa. The elastic anisotropy, average acoustic velocity and Debye temperature of Bct-C8 at ambient and high pressures were studied. The ideal stresses at large strains of Bct-C8 were examined; the results showed that it would cleave under the tensile strength of 72 GPa or under the shear strength of 70 GPa, indicating that Bct-C8 is a potential superhard material.

The effects of scandium (Sc) solute addition on the structural stability, mechanical strength, and electronic structure of magnesium-lithium (Mg-Li) ordered alloy were comprehensively studied by first-principles calculations. Two kinds of MgLi-Sc substitutional alloys (Mg-substituted Mg8−xLi8Scx and Li-substituted Mg8Li8−xScx) hold cubic lattice symmetry and become more stable with the increase in Sc content. The mechanical properties, including single crystal elastic constants, polycrystalline elastic moduli, and elastic anisotropy behaviors, have been systematically studied for two considered MgLi-Sc substitutional alloys. It was found that Mg8Li8−xScx exhibits larger elastic moduli than those of Mg8−xLi8Scx with the same Sc content; however, the derived elastic moduli of two substitutional alloys showed nonlinear variations as a function of Sc addition. Calculated stress–strain curves show an increasing of ideal tensile strengths and critical strains of the MgLi-Sc substitutional alloys along the and directions with Sc addition, indicating that the cubic MgLi-Sc substitutional alloy is mechanically harder and less brittle at higher Sc content. Furthermore, the developments of the electronic structures of two types of the studied alloys with increasing Sc addition were also investigated by the density of states and electronic localization function calculations.

An investigation of the mechanical, electronic, and optical properties of the recently reported material K4 phosphorus was made in this work. K4 phosphorus has been proved to be mechanically and dynamically stable up to 7 GPa under hydrostatic pressure. We compared the elastic anisotropy, average acoustic velocity, and Debye temperature of K4 phosphorus at 0 and 7 GPa. The ideal tensile properties at large strains of K4 phosphorus were also examined, with the results showing that it would cleave under the tensile strength of 8.5 GPa with the strain of 0.3. In addition, the effect of tensile strain and pressure on optical properties and band gap were studied.

Tungsten borides with excellent mechanical properties have been recognized as a class of ultrahard compounds in various industrial applications. Here, motivated by the recent experimental work, a quantitative comparison analysis on the structure, mechanical strength, and electronic structure of the tantalum-strengthened superhard W 0.5 Ta 0.5 B monoboride and its parent material WB has been studied by first-principles calculations. Excellent agreements of the calculated lattice parameters and simulated X-ray diffraction between present results and experimental data have confirmed the crystal structure of the synthesized W 0.5 Ta 0.5 B. Compared to the WB, the calculated stress-strain curves show an enhanced shear strength and improved ductility of W 0.5 Ta 0.5 B on (100) and (010) crystal planes, originating from the reduction of antibonding states between the W- e g states which enables strenuous sliding of metal bilayer in W 0.5 Ta 0.5 B. Furthermore, the lattice instability of W 0.5 Ta 0.5 B under large shear strain with an intriguing sequential bond-breaking mode that is derived from the first breaking of zigzag B chains and the subsequent collapsing of WB 7 and TaB 7 polyhedrons by simultaneously breaking of B–W and B–Ta bonds. These findings shed strong light on the strengthening mechanism of W 0.5 Ta 0.5 B and the design for novel ultra-incompressible and superhard solids in transition metal monoborides.

Based on the first-principles calculations, the strain effects on the optical properties of direct band gap silicon crystal D135-Si were systemically investigated. The stress-strain relations and phonon spectra show that the realistic peak tensile strengths in three principle symmetry crystallographic directions [100], [010] and [001] are 4.5, 9.7 and 12.1 GPa, respectively. By imposing the pressure and strain on structure, we studied the direct-indirect band gap transitions and obtained the ranges of the direct band gap, namely 0–4 GPa on pressure, −0.07–0, −0.04–0.08, and −0.01–0.03 on strain along a-, b- and c-direction, respectively. The imaginary part of the dielectric function was calculated to analyze the optical absorption property, which shows the strong adsorption coefficients in the visible range of the sunlight. The effect of pressure on the optical absorption property of structure is the smallest, and the strain effects are gradually enhanced along c-, b- and a-direction, respectively.

Heat shock protein 90 (HSP90) inhibition has aroused increasing enthusiasm in antitumor strategies in recent years. According to our previous studies, we synthesized a series of coumarin pyrazoline compounds HCP1-HCP6 that might be HSP90 inhibitors. Interactions between HCP1-HCP6 and HSP90 were examined and antitumor activities of them were investigated in A549 lung cancer cells. Results showed that all the six derivatives could interact with HSP90, in which HCP1 exhibited the best binding ability and inhibited the activity of HSP90. Meanwhile, HCP1-HCP6 reduced the cell viability of A549 cells and HCP1 possessed the lowest IC50 value. Above all HCP1 exerted better HSP90 inhibitory and anticancer effects than our initially identified HSP90 inhibitor DPB. As to the underlying mechanism, HCP1-HCP6 not only induced apoptosis as DPB but also blocked autophagic flux in A549 cells. Therefore, we discovered a novel HSP90 inhibitor HCP1 that had better biological activity and provided us a useful tool to explore the underlying mechanism of lung cancer therapy.

A new all-sp3 hybridized orthorhombic superhard carbon phase Fmmm-C80 (space group: Fmmm) with direct band gap and low density is uncovered by using CALYPSO code and first-principles calculations. The unit cell of Fmmm-C80 phase contains 80 carbon atoms, and its thermodynamic stability is confirmed by the phonon and molecular dynamics simulations. The semiconducting nature of the Fmmm-C80 was revealed by the calculated direct band gap of 4.11 eV. Also, Fmmm-C80 is found to be a potential superhard carbon phase for its large Vickers hardness of 51 GPa.

Microalgal biofilm has been recognized as a cost-effective biorsorbent for heavy metal and a promising method for microalgae-water separation. In this study, living suspended Scenedesmus obliquus FACHB-12 (isolated from southern China) and its biofilm with different carriers were investigated to remove cadmium from aqueous solution. S. obliquus FACHB-12 biofilm with luffa sponge carrier showed highest cadmium removal efficiency at 92.7% compared to biofilm with K3 carrier (75.3%) and significantly higher than suspended S. obliquus FACHB-12 (61.8%) in 2 h experiment with initial Cd2+ concentration at 3.0 mg/L at pH = 6.0 with 0.8 g/L of biomass under room temperature. S. obliquus FACHB-12 biofilm with K3 and luffa sponge carrier also demonstrated higher tolerance towards increased Cd2+ concentration with highest biosorption efficiency at 85.1% and 90.35% respectively under 20 mg/L of Cd2+, while suspended S. obliquus FACHB-12 biosorption efficiency achieved 81.4% under 10 mg/L of Cd2+ and started to decline over increased cadmium concentration. The adsorption kinetics for all experimental groups followed the pseudo-second-order adsorption model, with biosorption equilibrium favored in Langmuir isotherm. The maximum biosorption capacity estimated by Langmuir isotherm reached 133.14 mg/g biomass in S. obliquus FACHB-12 biofilm with luffa sponge carrier, followed by 78.76 mg/g with K3 carrier, and 60.03 mg/g with suspended S. obliquus FACHB-12. Results suggest an efficient, inexpensive microalgal biofilm with biological carrier system could enhance high cadmium removal for advanced wastewater treatment and provide a cost-effective method for microalgae harvesting process.

We predict the existence of new two dimensional (2D) silicon carbide nanostructures employing ab initio density-functional theory calculations. These structures are composed of tetragonal and hexagonal rings with C─C and Si─C bonds arranged in a buckling plane. They are proven to be thermodynamically and mechanically stable with relatively low formation energy, implying potential fabrication in labs. They exhibit strong ductility and anisotropicity from their strain-stress relations and directional dependence of mechanical moduli. The materials maintain phonon stability upon the application of mechanical strain up to 27% with fantastic ductile property. The proposed 2D SiC2 structure possesses a tiny direct band gap of 0.02 eV predicted using HSE06 functional and the band gap can be opened up through multiple approaches such as hydrogenation and strain application. The gap values can be strategically tuned in the range of 0.02–1.72 eV and the direct/indirect gap nature can be further manipulated. In contrast, a closely related isostructural 2D SiC shows an indirect HSE band gap of 1.80 eV and strain engineering its value between 0.0–1.95 eV. The unique properties in these newly proposed structures might have potential applications in future nanomechanics and electronics.

Calcineurin (CN) is involved in many physiological processes and interacts with multiple substrates. Most of the substrates contain similar motifs recognized by CN. Recent studies revealed a new CN substrate, transcription factor EB (TFEB), which is involved in autophagy. We showed that a 15-mer QSYLENPTSYHLQQS peptide from TFEB (TFEB-YLENP) bound to CN. When the TFEB-YLENP peptide was changed to YLAVP, its affinity for CN increased and it had stronger CN inhibitory activity. Molecular dynamics simulations revealed that the TFEB-YLENP peptide has the same docking sites in CN as the 15-mer DQYLAVPQHPYQWAK motif of the nuclear factor of activated T cells, cytoplasmic 1 (NFATc1-YLAVP). Moreover expression of the NFATc1-YLAVP peptide suppressed the TFEB activation in starved Hela cells. Our studies first identified a CN binding site in TFEB and compared the inhibitory capability of various peptides derived from CN substrates. The data uncovered a diversity in recognition sequences that underlies the CN signaling within the cell. Studies of CN-substrate interactions should lay the groundwork for developing selective CN peptide inhibitors that target CN-substrate interaction in vitro experiments.

Quercitrin (YDHH) is a natural dietary flavonoid extracted from Tartary buckwheat ( Fagopyrum tataricum (L.) Gaertn.). Psoriasis is a chronic immune-mediated dermatosis. In this study, we report that YDHH had no obvious cytotoxicity and inhibited the proliferation of LPS-stimulated HaCaT keratinocytes. Furthermore, oral administration of YDHH alleviated imiquimod-induced psoriasis-like dermatitis in mice, significantly attenuating the excessive proliferation and abnormal differentiation of keratinocytes, and reducing inflammatory cell infiltrates. YDHH treatment lowered the expression of cytokines related to psoriasis, especially those on the IL-23/Th17 axis. Furthermore, it dramatically inhibited the Th17 cell response regulated by the JAK/STAT signalling pathway. In addition, it was less toxic to the liver and kidneys of mice than the classical immunosuppressant cyclosporine A. Taken together, these findings indicate that YDHH could be useful as a functional food supplement for protection against psoriasis.

The structural, elastic, elastic anisotropic, thermodynamic and electronic properties of Lonsdaleite C, Si and Ge and Lonsdaleite C–Si and Si–Ge alloys are investigated using density functional theory. The elastic anisotropy calculations show that the Lonsdaleite C0.25Si0.75 alloy has the greatest anisotropy in Poisson’s ratio, shear modulus, bulk modulus and Young’s modulus. Through the mixing of carbon and silicon and silicon and germanium at certain proportions, Lonsdaleite C0.25Si0.75 with metallic properties and Lonsdaleite Si0.25Ge0.75 with a direct band gap are obtained, where Lonsdaleite Si0.25Ge0.75 is a narrow direct band gap semiconductor with a band gap of 0.76 eV at the HSE06 hybrid functional level. The minimum thermal conductivity calculations on Lonsdaleite C–Si and Si–Ge alloys show that the minimum thermal conductivities of Lonsdaleite C0.75Si0.25 and Lonsdaleite C0.5Si0.5 are greater than that of diamond C, and the minimum thermal conductivities of Lonsdaleite C–Si and Si–Ge alloys in different directions are also investigated.

A Gram-staining-positive, aerobic non-spore-forming and short-rod-shaped endophytic actinomycete was isolated from a branch of Sonneratia apetala, designated strain BGMRC0092T and investigated in detail data to determine its taxonomic position. On the basis of the 16S rRNA gene sequence analysis, the results of the phylogenetic analyses indicated that BGMRC0092T was most closely related to Nocardioides alpinus Cr7-14T (96.9 %), Nocardioides oleivorans DSM16090T (96.4 %) and Nocardiodes exalbidus RC825T (96.3 %). The predominant cellular fatty acids of BGMRC0092T were iso-C16 : 0 and C18 : 1ω8c. The major menaquinone was MK-8(H4). The diagnostic diamino acid in the cell-wall peptidoglycan was ll-2,6-diaminopimelic acid. The predominant cell-wall sugars were composed of galactose, mannose, rhamnose and xylose. The polar lipid pattern contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, one unknown phospholipid and three unknown polar lipids. The DNA G+C content was 69.3 mol%. On the basis of phenotypic and chemotaxonomic characteristics and the results of phylogenetic analysis, BGMRC0092T represents a novel species of the genus Nocardioides , for which the name Nocardioides sonneratiae sp. nov. is proposed. The type strain is Nocardioides sonneratiae BGMRC0092T (=KCTC 39565T=NBRC 110251 T=DSM 100390T).

The cysteine‐rich lysosomal protein placenta‐specific 8 (PLAC8), also called onzin, has been shown to be involved in many types of cancers, and its role is highly dependent on cellular and physiological contexts. However, the precise function of PLAC8 in breast cancer (BC) progression remains unclear. In this study, we investigated both the clinical significance and biological functions of PLAC8 in BC progression. First, high PLAC8 expression was observed in primary BC tissues compared with adjacent normal tissues through immunohistochemistry analysis. The results of in vitro and in vivo assays further confirmed that PLAC8 overexpression promotes cell proliferation and suppress BC cell apoptosis, whereas PLAC8 silencing has the opposite effect. In addition, the forced expression of PLAC8 greatly induces cell migration, partially by affecting the EMT‐related genes, including down‐regulating E‐cadherin expression and facilitating vimentin expression. Further mechanistic analysis confirmed that PLAC8 contributes to cell proliferation and suppresses cell apoptosis in BC by activating the PI3K/AKT/NF‐κB pathway. The results of our study provide new insights into an oncogenic role of PLAC8 and reveal a novel PLAC8/ PI3K/AKT/NF‐κB pathway as a potential therapeutic target for BC.

Vascular endothelial cell (VEC) apoptosis takes part in the development of various cardiovascular diseases. Heat shock protein 90 (HSP90) regulates apoptosis through various apoptosis associated client proteins. In previous study, we identified a novel HSP90 inhibitor HCP1 induced apoptosis in A549 human lung cancer cells. Here, we found that low-concentration HCP1 (1 μM, 2 μM) suppressed VEC apoptosis caused by serum and fibroblast growth factor 2 (FGF-2) deprivation. HCP1 directly bound to glucose-regulated protein 94 (Grp94), an isoform of HSP90 located in endoplasmic reticulum, and HCP1 selectively inhibited Grp94 activity via binding to site 3. Overexpression of Grp94 inhibited the anti-apoptotic effect of HCP1 in human umbilical vein endothelial cells. Therefore, we provided HCP1 as a new VEC apoptosis inhibitor which might be a potential compound in the treatment of VEC apoptosis related vascular diseases. And we provided new pieces of evidence to understand the role of Grp94 in VEC apoptosis.

A new structure of NbN (P62m-NbN) is predicted by first-principles density functional theory calculations. For the new structure and P6m2, Pm3m and P63mmc-NbN, they are stable according to elastic, dynamic, thermodynamic and chemical stability, under 0 GPa, 20 GPa, 40 GPa, 60 GPa, 80 GPa, and 100 GPa pressure. Their physical properties are calculated, under 0 GPa, 20 GPa, 40 GPa, 60 GPa, 80 GPa, and 100 GPa pressure. For P6m2, Pm3m and P63mmc-NbN under 0GPa pressure, the calculated physical properties are in excellent agreement with the early ones, indicating the reliability of the approach. To the best of our knowledge, the physical properties of four NbN phases under 20GPa to 100GPa pressure are the first attempt to explore and compare. P6m2-NbN is harder to compress and P62m-NbN is easier to compress. The P6m2-NbN is the stiffest material and P62m-NbN is the softest material at 0 GPa pressure. Pm3m-NbN is the stiffest material at 100 GPa pressure. The P6m2-NbN is close to shear isotropy. The Debye temperatures are 760 K, 735 K, 707 K and 684 K for P6m2, Pm3m, P63mmc and P62m-NbN, respectively, at 0 GPa. The Debye temperature of P62m-NbN is the minimum in four NbN phases, from 0GPa to 100GPa. The Debye temperature of Pm3m-NbN is the maximum in four NbN phases, from 20GPa to 100GPa. Four NbN structures are conductors both at 0GPa and 100GPa pressure.

Tomato is a popular healthy fruit worldwide because it is rich in secondary metabolites such as vitamin C. Deficit irrigation (DI) can be applied to improve tomato fruit quality to a certain degree and save water consumption. However, the effects of DI on tomato quality are complex and affected by factors such as tomato variety and soil bulk density and texture. The objective of this paper is to use meta-analysis to 1) investigate the effects of DI on tomato quality variables and 2) study how soil texture, soil bulk density and three tomato varieties affect quality variables under DI compared to those under full irrigation. We collected 83 research papers from around the world and analyzed 2369 data pairs. Overall, DI increased the total soluble solids (12.44%), soluble sugar (11.23%), organic acids (6.58%), sugar/acid content ratio (14.56%), vitamin C (13.84%), lycopene (10.46%), color index (8.42%), red-green value (11.89%), shape index (3.25%) and firmness (12.09%) while decreasing β-carotene, lightness, hue angle and yellow-blue value by 11.11%, 1.77%, 3.42% and 4.26%, respectively. In addition, DI had no significant effects on tomato chroma (0.89% on average; 95% CI: -0.96% to 2.79%) or pH (0.13% on average; 95% CI: -0.26% to 0.52%). The results indicated that it would be better to apply deficit irrigation in fine and coarse soil, because most of the quality variables improved more in these soil textures than in medium soil. Soil with a bulk density of 1.2∼1.4 g cm-3 benefited taste quality, vitamin C and shape index. The quality of the three tomato varieties responded differently to water deficit conditions. Moreover, cherry tomato responded better to water deficit conditions than the other two tomato varieties; four quality variables improved the most in cherry tomato and two other variables were also improved. Our findings could help to obtain a better understanding of how fruit quality responds to DI in different soil textures, soil bulk densities and tomato varieties and to produce higher-quality tomatoes.

A new cubic superhard large-cell carbon allotrope with 200 carbon atoms per unit cell (named c-C200) is theoretically predicted by the unbiased swarm structure searching techniques combined with the first-principles calculations. The phonon and elastic constants calculations show that c-C200 is dynamically and mechanically stable. The calculated hardness of c-C200 is 47 GPa, which means that c-C200 is a potential superhard material. The calculated electronic band structure of c-C200 shows that it is a quasi-direct band gap semiconductor with a gap of 2.781 eV.

A new neo-lignan, (7′ S,8 ′R)-4′,5′,9′-trihydroxy-4,6-dimethoxy-5,8′-oxyneolign-7-en-9-al (1), along with 5 known compounds (2-6), were isolated from the fruits of Xanthium strumarium. Their structures were elucidated by extensive spectroscopic methods. All the isolates were evaluated for in vitro cytotoxicities against the human cancer lines HepG2, A549, HCT-116, and SGC-7901. Compounds 1 and 3 showed potent antiproliferative effects against A549 cancer cells with half-maximal inhibitory concentration (IC50) values of 11.2 and 8.3 µM, respectively. In addition, compound 3 exhibited moderate cytotoxicity to SGC-7901 cancer cells, with an IC50 value of 12.9 µM.

Bacillus pumilus SWU7-1 was isolated from strontium ion (Sr(II))-uncontaminated soil, its biosorption potential was evaluated, and the effect of γ-ray radiation treatment on its biosorption was discussed. Domesticated under Sr(II) stress promoted the biosorption ability of B. pumilus to Sr(II), and the biosorption efficiency increased from 46.09% to 94.69%. At a lower initial concentration, the living bacteria had the ability to resist the biosorption of Sr(II). The optimal initial concentration range was 54–130 mg/L. The biosorption profile was better matched by Langmuir than Freundlich model, showing that the biosorption process of Sr(II) by the experimental strain was closer to the surface adsorption. According to Langmuir model, the maximum biosorption capacity of B. pumilus on Sr (II) was 299.4 mg/g. During the bacterial growth in the biosorption process, the changes in biosorption capacity and efficiency can be divided into two phases, and a pseudo-second-order model is followed in each phase. There was no significant difference in the biosorption efficiency of bacteria with different culture time after γ-ray radiation, and all of them were above 90%, which showed that B. pumilus had significant radiation resistance under experimental conditions. This study emphasized the potential application of B. pumilus in the treatment of radioactive Sr(II) pollution by biosorption.

A novel superhard carbon allotrope C64 is predicted which is composed of C28 cages. It is porous and exhibits distinct topologies including zigzag 5, 6, 8, 10 and 12-fold carbon rings. The elastic constants and phonon calculations reveal that C64 is mechanically and dynamically stable at ambient pressure. The hardness of C64 is 60.2 GPa. The tensile and shear strength calculations indicate that the lowest tensile and shear strengths have the almost same value of 48.1 GPa. For the electronic properties, the band structure calculations show that C64 is a quasi-direct band gap semiconductor with a band gap of 1.32 eV.