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The anticancer potential of quassinoids has attracted a great deal of attention for decades, and scientific data revealing their possible applications in cancer management are continuously increasing in the literature. Aside from the potent cytotoxic and antitumor properties of these degraded triterpenes, several quassinoids have exhibited synergistic effects with anticancer drugs. This article provides an overview of the potential anticancer properties of quassinoids, including their cytotoxic and antitumor activities, mechanisms of action, safety evaluation, and potential benefits in combination with anticancer drugs.

For graphs Gand H, the Ramsey number R(G, H) is the minimum integer Nsuch that any coloring of the edges of the complete graph KNin red or blue yields a red Gor a blue H. Denote the union of tdisjoint copies of a graph Fby tF. We call tK2a stripe. In this paper, we completely determine Ramsey numbers of stripes versus trees and unicyclic graphs. Our result also implies that a tree is tK2-good if and only if the independence number of this tree is no less than t. As an application, we improve the known Ramsey numbers of stars versus fan graphs. Moreover, we determine the bipartite Ramsey numbers of a connected bipartite graph versus stripes.

Puccinia striiformisWestend. f. sp. triticiErikss. (Pst) infects wheat and causes stripe rust. The rust is heteroecious with wheat as the primary uredinial and telial host and barberry (Berberisspp.) as the alternate pycnial and aecial host. More than 40 Berberisspecies have been identified as alternate hosts for Pst, and most of these are Chinese Berberisspecies. However, little is known about Berberisspecies or their geographic distributions in the Yunnan-Guizhou plateau in southwestern China. The Yunnan-Guizhou plateau is considered to be an important and relatively independent region for the evolution of the wheat stripe rust pathogen in China because the entire disease cycle can be completed within the region. In this study, we conducted a survey of barberry plants in the Yunnan-Guizhou plateau and identified the eight Pst-susceptible Berberisspecies under controlled conditions, including B. julianae, B. tsienii, B. veitchii, B. wilsonae, B. wilsonaevar. guhtzunica, B. franchetiana, B. lepidifoliaand B. pruinosa. These species are reported here for the first time to serve as alternate hosts for the wheat stripe rust pathogen under controlled conditions.

In recent years, two-dimensional (2D) group VA elemental materials have attracted considerable interest from physics/chemistry and materials science communities, with particular attention paid to honeycomb blue phosphorene. To date, phosphorene is limited to its α-phase and small sizes because it can only be produced by exfoliating black phosphorus crystals. Here, we report the direct synthesis of high-quality phosphorene on a nonmetallic copper oxide substrate by molecular beam epitaxy. By combining scanning tunneling microscopy/spectroscopy, X-ray photoelectron spectroscopy, and first-principles calculations, we demonstrate the growth intermediates and electronic structures of phosphorene on Cu3O2/Cu(111). Surprisingly, the grown phosphorene has a flat honeycomb lattice, similar to graphene, which exhibits a metallic nature. We reveal that the growth mechanism and morphology of phosphorene are strongly correlated with the surface structures of prepared copper oxide, and the resulting phosphorene can be stabilized after high-temperature annealing above 600 K even in oxygen gas. The high stability is closely related to the irregular Moiré pattern and structural corrugations of phosphorene on Cu3O2/Cu(111) that efficiently relieve the surface strain. These results shed light on future fabrication of large-scale, versatile 2D structures for interconnect and device integration.

•We study Ising model on a decorated square structure with mixed-spin (2, 3/2).•Dynamic magnetic behaviors of the system were examined in the framework of Monte Carlo simulations.•The crucial physical quantities, such as magnetic entropy change and relative cooling capacity, are being examined for the study of magnetic refrigeration.•Time oscillating magnetic field imposes magnetic disorder in the system.•Compensation behavior was demonstrated in |Ds|≥4.1 and the system displays two compensation points at |Ds| = 4.1.

Hydrogen is the energy carrier with the highest energy density and is critical to the development of renewable energy. Efficient hydrogen storage is essential to realize the transition to renewable energy sources. Electrochemical hydrogen storage technology has a promising application due to its mild hydrogen storage conditions. However, research on the most efficient electrochemical hydrogen storage materials that satisfy the goals of the U.S. Department of Energy remain open questions. All of the above require strategies for designing new hydrogen storage materials. This review provides a brief overview of hydrogen preparation, hydrogen storage, and details the development of electrochemical hydrogen storage materials. We summarize the electrochemical hydrogen storage capabilities of alloys and metal compounds, carbonaceous materials, metal oxides, mixed metal oxides, metal–organic frameworks, MXenes, and polymer-based materials. It was observed that mixed metal oxides exhibit superior discharge capacity and cycling stability. The review indicates that it is vital to create novel materials with large surface area, active-conductive profiles, and low cost. We describe the challenges, gaps, and future perspectives of electrochemical hydrogen storage materials, and hope that the review could draw more attention to the development of electrochemical hydrogen storage materials with high hydrogen storage capacity, high safety, high cycle stability, and low cost and promoting their practical applications.

Construction 3D printing (C3DP) has emerged as an important force in automation and sustainable transformation of the construction industry. Despite the implementation of numerous incentive policies, its development and application remain at a relatively slow pace in developing countries. This research employs the Q methodology to explore the perspectives of China's stakeholders on the innovation policies for the development and application of C3DP. The study reviews the development of C3DP in China and identifies statements related to C3DP promotion policy and development. Based on data from C3DP industrial experts, the results reveal four distinct policy perspectives: conservative exploration, aggressive progression, intensive investigation, and tentative stimulation. A consensus exists that provides direction for policymaking though the divergences among stakeholders highlight the complexity of implementing policy mixes. This study has theoretical and practical significance in supporting policy mixes for C3DP development and adoption in fast-growing areas.

Epitaxial two-dimensional (2D) nanostructures with regular patterns show great promise as templates for adsorbate confinement. Prospectively, employing 2D semiconductors with reduced density of states leads to a long excited-state lifetime that allows us to directly image the dynamics of the adsorbate. We show that epitaxial blue phosphorene (blueP) on Au(111) provides such a platform to trap water molecules in the periodic nanopores without formation of strong bonds. The trapped water aggregate is tentatively assigned to a hexamer based on our scanning tunneling microscopy studies and first-principles calculations. Real-space observation of conformational switching of the hexamer induced by inelastic electrons is achieved by using low-temperature scanning tunneling microscopy with molecular resolution. We found a localized interfacial charge rearrangement between the water hexamer and P atoms underneath that is responsible for the reversible desorption and adsorption of water molecules by changing the sample bias polarity from positive to negative, offering a promising strategy for engineering the electronic properties of blueP.

We present molecular beam epitaxial growth of blue phosphorene (BlueP), a new allotrope of black phosphorene, on Au(111) and its surface functionalization with fullerene (C60) molecules by low-temperature scanning tunneling microscopy and scanning tunneling spectroscopy (STS). In contrast to the well-ordered aggregation on conventional surfaces, C60molecules favor to adsorb at the domain boundaries of BlueP and create defects and a disordered phase nearby. STS reveals a shift of the conduction band minimum of BlueP and a remarkable broadening of the lowest unoccupied molecular orbital of C60, indicating an interfacial charge transfer. In addition, codeposition of C60with phosphorous precursors on Au(111) followed by annealing generates a new reconstruction of BlueP comprising larger triangles and higher density of dislocation lines that are favorable for anchoring bulky C60balls.

In aromatic systems, π–π interaction plays a central role in determining the stacking geometry and binding strength of molecules and thus a detailed microscopic understanding is highly desirable. Herein, by using scanning tunneling microscopy with submolecular resolution complemented with first-principles calculations based on density functional theory, we report the atomic-scale imaging of π–π interaction in nonplanar phthalocyanine (Pc) bilayers on different substrates, including graphite and Au(111) with weak interaction and Cu(111) with strong binding. We reveal that nonplanar Pc of the second layer on all substrates exhibits an in-plane rotation angle of 15° with a parallel offset of 1.19 Å, which minimizes π–π repulsion. Interestingly, on Cu(111), it is found that the inequivalent charge distribution along with the alternating orientation of Pc molecules in the first layer creates a preferable anchoring site for Pc of the second layer, leading to the assembly of the √2 × √2R45° superstructure, consistent with theoretical calculations showing that π-systems with extra negative charge have weaker interlayer binding energy. Our joint experimental–theoretical efforts provide direct evidence for the most energetically favorable parallel offset π–π stacking and charging effects on the preferential interaction between aromatic rings, which may shed new light on molecular assembly and organic nanoelectronics.

Glycogen synthase kinase 3 (GSK3) is a kind of serine/threonine kinase widely found in eukaryotes. Many plant GSK3 kinases play important roles in regulating stress responses. This study investigated BRASSINOSTEROID-INSENSITIVE 2(GmBIN2) gene, a member of the GSK3 protein kinase family in soybean and an orthologue of Arabidopsis BIN2/AtSK21. GmBIN2expression was increased by salt and drought stresses, but was not significantly affected by the ABA treatment. To examine the function of GmBIN2,transgenic Arabidopsisand transgenic soybean hairy roots were generated. Overexpression of GmBIN2in Arabidopsisresulted in increased germination rate and root length compared with wild-type plants under salt and mannitol treatments. Overexpression of GmBIN2increased cellular Ca2+content and reduced Na+ content, enhancing salt tolerance in transgenic Arabidopsisplants. In the soybean hairy root assay, overexpression of GmBIN2in transgenic roots also showed significantly higher relative root growth rate than the control when subjected to salt and mannitol treatments. Measurement of physiological indicators, including proline content, superoxide dismutase (SOD) activity, and relative electrical conductivity, supported this conclusion. Furthermore, we also found that GmBIN2could up-regulate the expression of some stress-related genes in transgenic Arabidopsisand soybean hairy roots. Overall, these results indicated that GmBIN2improved tolerance to salt and drought in transgenic Arabidopsisand soybean hairy roots.

The effects of casting currents on the thermophysical behaviors, atomic and nanoscale structure, and mechanical properties of two Zr-based-bulk metallic glasses, i.e., Zr59Cu33Al8and Zr59(Cu0.55Fe0.45)33Al8, were studied by using differential scanning calorimetry, wide-angle X-ray diffraction, and small-angle X-ray scattering, as well as compression tests. The casting currents can be tuned to change the casting initiative temperature. Results revealed that there is no anomalous structural change for the Zr59Cu33Al8molten liquid before crystallization during cooling with different casting currents. In contrast, liquid-state phase separation was suggested to occur in the Zr59(Cu0.55Fe0.45)33Al8molten liquid prepared using lower casting current before crystallization during cooling. The position shift of the first sharp diffraction peak for the diffraction pattern of Zr59(Cu0.55Fe0.45)33Al8shows that the density of the molten liquid may decrease upon cooling at different casting currents. The small-angle X-ray scattering results indicate that the heterogeneity of the Zr59(Cu0.55Fe0.45)33Al8metallic glasses increases with decreasing the casting temperature. As a result, the metallic glasses with a liquid-state phase separation possess better mechanical properties, including higher-yielding stress and more significant compressive ductility. The increase in degree of heterogeneity formed by nanoscale liquid-state phase separation and their interactions with the shear bands for the Zr–Cu–Fe–Al bulk metallic glasses were suggested to be responsible for the enhanced mechanical properties.

Liquid crystal was chosen as an optical probe for the investigation of the interactions of alkyl polyglycosides with proteins at the liquid crystal-aqueous interface. The luminous changes in the LC films were used as a readout.

Reduction of diesel engine emissions is now getting more and more focuses from automobile manufacturers as the legalization is becoming stricter. In this paper we use AVL FIRE to simulate and analyze the influence of ω-type combustion chamber shapes on raw emissions of a diesel engine. We get the conclusion that the trend of original exhausts, NOx and soot, decreases without power loss with the ratio TDD of throat diameter and depth of the chamber reducing. And considering the original emission control technologies of the experiment engine, a smaller ratio TDD will contribute to better emission.

Computerized well logging equipment plays an important role in petroleum exploration and production, and data acquisition system is the core of it. In order to improve the acquisition systems which are used in some oil fields in recent years, a new design of data acquisition system is introduced. The ARM embedded chip and the FPGA chip are the kernel chips of the data acquisition system, and the Ethernet is the communication medium between the cards of the data acquisition system and the host computer of the numerical controlled well logging system. This data acquisition system has more integrated level and communication speed higher than the others of same kind.

The paper addresses the central issues of electromagnetic compatibility (EMC) evaluation of shipborne electronic equipment. The mutual disturbance between equipments would show important influence on the capability of the devices, slight interferer may degrade the performance, severe interferer would make the equipment out of work even cause false action of weapon system, therefore, how to quantitatively describe the EMC state of equipment and harmonize the EMC assessments correctly is the key consideration of the warship’s commander and the combat system designer. Take the advantage of norm theory this paper proposed a method to evaluate the EMC state of the shipborne electronic equipment quantitatively, which would meet the requirements both warship’s EMC design and commander’s campaign operation.

The cable support system in large cross-section cable tunnel, which can solve the cable laying problem of big cross section cable and multi-loop cable effectively, gradually become the development trend of urban electricity transmission. Combined with the structure feature of large cross section shield tunnel, a new type of self-balanced shield tunnel cable support system is proposed. The safety and rationality of this system has been validated by the structure calculation, the finite element analysis of ADINA and the full scale model test. The analysis shows that the system has some advantages, such as excellent whole mechanical characteristics, strong adaptability, convenient construction and low cost. The system can fully satisfy all requirements of the cable tunnel construction and all functions of operation. The stress distribution of the structure is relatively homogeneous, the bearing capacity of components and the global stability of it also meet the requirements. With the test load which is about 1.5 ~ 4.0 times as large as design load, the support system displacement is 0.65 ~ 2.5 mm, which shows that the structure is safe and reliable. The research achievements can provide theoretical basis and experimental basis for the design of large cross-section cable tunnel.

To investigate the fatigue property of carbon structural steel in theory, the microstructure and properties of quenched martensite must be studied in detail. In this paper, the electronic structure and mechanical properties of carbon structural steel in quenched state were calculated by the empirical electron theory of solids and molecules (EET). The relationship between electronic structure parameters and mechanical properties of martensite was investigated. The mechanical properties of quenched carbon structural steel were calculated theoretically, and the result of theoretical calculation is consistent with the experiment result.

A rapid and validated method was established for the simultaneous determination of eight active and toxic bufadienolides in cinobufacini injection using high performance liquid chromatography coupled with triple quadrupole mass spectrometry. These eight compounds were separated within 3 min on a C18analytical column with gradient elution. Eleven batches of cinobufacini injection were analyzed with good linear regression relationship (r, 0.9979–0.9999), precisions (RSD, 1.92–4.79%), repeatability (RSD, 3.12–4.96%), stability (RSD, 2.84–4.45%), and recovery (93.96–104.89%). By using the established method, the present study offered highly sensitive, specific, and speedy determination of eight bufadienolides, which promoted the quality control investigation of cinobufacini injection greatly.

A highly selective method for the synthesis of N‐9 alkylated purine nucleoside derivatives viaan intermolecular hydrogen abstraction reaction between nitrogen radicals in purine rings and alkyl ethers was developed. Novel purine nucleoside derivatives were obtained with good to high yields in the presence of (diacetoxyiodo)benzene (DIB) and iodine in one‐step reaction.

By using artificial non-homogeneous cores which coefficient of variation is 0.72 to simulate reservoir sandstone, and proceed the research of displacement effect on three aspects, which are polymer molecular weight, polymer solution concentration and reservoir permeability. The results show that polymer solution concentration and polymer molecular weight have greater influence on the displacement efficiency, while reservoir permeability has very little influence when it is more than 700md.

To handle semantic heterogeneity, enhance semantic interoperability and achieve automatic understanding and managing of services in the SOA integrated systems, semantic support was required and the SOA should be extended to the semantic SOA (SSOA). For complex product advanced manufacturing systems, a knowledge base (KB) was built by analyzing and abstracting multidisciplinary knowledge of complex product fields. Based on the KB, a knowledge base system (KBS) architecture was proposed to provide semantic support for information sharing and exchanging at the knowledge level.

The amoeba‐cyst cycle of Paramoebidium(Amoebidiales) is described as it develops in the rectum of its larval insect hosts and in the external aquatic environment. Numerous wall channels with associated vesicles aggregated at the apical end of the cystopores may allow rapid extrusion of holdfast material through the wall, in a manner resembling holdfast formation by sporangiospores of Amoebidium parasiticum. It is suggested that the cysts, in addition to their possible resistance to adverse environmental conditions, may function as timing devices to insure establishment of thalli in the proper location in the rectum. A new species is described, P. curvumLichtwardt, which was found to contain polyhedral viruslike particles scattered in the cytoplasm.

Binary two-dimensional (2D) materials comprising main group elements with several phases of AB and AB2stoichiometry provide significantly rich physics and application potentials. We present the epitaxial growth of two phases of atomically thin SnSb on a Cu2Sb surface alloy under ultrahigh-vacuum (UHV) conditions. Theoretical studies predict that these 2D SnSb sheets adopt the atomic configurations similar to those of black and blue phosphorene but with Sb–Sn–Sn–Sb motif (R- and H-phases) holding an indirect band gap of 0.20 and 0.85 eV, respectively. Our low-temperature (77 K) scanning tunneling microscopy characterizations, and first-principles theoretical calculations, reveal the atomic structures and semiconducting properties of the most stable H-phase, displaying a commensurate lattice growth mode on Cu2Sb(111) but a weak interfacial interaction. Strain-engineered band gap, effective mass, and Young’s Modulus of the most stable H-phase are further explored theoretically. These results suggest that 2D SnSb with intriguing properties has great potential for electronics in an atomically thin platform.

Successful cloning by somatic cell nuclear transfer (SCNT) requires overcoming significant epigenetic barriers. Genomic imprinting is not generally regarded as such a barrier, although H3K27me3-dependent imprinting is differentially distributed in E6.5 epiblast and extraembryonic tissues. Here we report significant enhancement of SCNT efficiency by deriving somatic donor cells carrying simultaneous monoallelic deletion of four H3K27me3-imprinted genes from haploid mouse embryonic stem cells. Quadruple monoallelic deletion of Sfmbt2, Jade1, Gab1, and Smoc1normalized H3K27me3-imprinted expression patterns and increased fibroblast cloning efficiency to 14% compared with a 0% birth rate from wild-type fibroblasts while preventing the placental and body overgrowth defects frequently observed in cloned animals. Sfmbt2deletion was the most effective of the four individual gene deletions in improving SCNT. These results show that lack of H3K27me3 imprinting in somatic cells is an epigenetic barrier that impedes post-implantation development of SCNT embryos and can be overcome by monoallelic imprinting gene deletions in donor cells.