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This study explored the friction and wear behavior of a Ni-based exhaust valve at high temperatures. Nickel-based superalloy was used with two types of processing states: the original forged sample and the sample under the standard T1 heat treatment. At room temperature and a loading force of 10 N, the average friction coefficient of the T1 heat-treated specimen is 0.61, which was lower than that of the forged sample (0.78). The wear rate of this specimen was also lower than that of the forged sample at the same temperature and loading force. Thus, T1 heat treatment can significantly improve the wear resistance of the alloy because of γ ′ phase and carbides. The wear rate was the minimum at 550∘C and increased again at 750∘C dominated by the formation and flake-off of the oxide film. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer (PC), the most commonly diagnosed malignancy, is also the second leading cause of cancer-related deaths. Although tremendous efforts have been achieved to improve the early detection of PC, it is still urgent to find out novel markers and therapeutic targets for PC patients. Homeobox protein MOX-1 (MEOX1) is found to be ectopically expressed in human cancers. This study aims to test the hypothesis that MEOX1 gene silencing might suppress the proliferation and invasion of LNCaP cells in PC.Materials and Methods: Microarray analysis was conducted to screen PC-related differentially expressed gene. MEOX1 was silenced to detect the relationship between silenced MEOX1 and cell proliferation, migration, apoptosis, and invasion. Expression of MEOX1, Bcl-2, p53, and Bax in LNCaP cells was determined using reverse transcription-quantitative polymerase chain reaction and western blot analysis. Cell proliferation, colony formation rate, cell migration, invasion, cell cycle, and apoptosis were detected respectively.Results: MEOX1 gene was found to be expressed highly in PC tissues. After MEOX1 was silenced in LNCaP cells, the mRNA and protein expression of Bcl-2 decreased while the mRNA and protein expressions of p53 and Bax increased. Additionally, cell proliferation, migration, and invasion were reduced while cell apoptosis was increased by MEOX1, and MEOX1 gene silencing was revealed to inhibit cell proliferation and decrease tumorigenic ability of LNCaP cells in nude mice.Conclusion: Taken together, MEOX1 gene silencing could decrease the proliferation and increase apoptosis of LNCaP cells, and so it is expected to be a therapeutic target for PC. [ABSTRACT FROM AUTHOR]

Objective. The traditional Chinese medicine Kangai injection as an adjuvant method in combination with chemotherapy has been widely used for treating breast cancer in clinical practice in China. This study systematically reviewed the clinical effect and safety of traditional Chinese medicine Kangai injection as an adjuvant method in combination with chemotherapy for treating Chinese patients with breast cancer. Methods. Seven databases were searched in this study, namely, PubMed, the Cochrane Library, Embase, CNKI, Sino Med, VIP, and Wanfang Data. The timeframe of retrieval was set from the founding date of each database to November 1, 2017. Results. Fifteen papers were included in this study. The quality of all the studies included was low. All the studies were carried out among the Chinese population. Meta-analyses showed that, compared with single-use chemotherapy, using a Kangai injection combined with chemotherapy to treat Chinese breast cancer patient can increase the total effective rate [RR = 1.15, 95% CI (1.01, 1.32), and P=0.033], improve the quality of life [RR = 1.30, 95% CI (1.14, 1.48), and P≤0.001], decrease the incidence of weight loss [RR = 0.49, 95% CI (0.32, 0.77), and P=0.002], decrease WBC count [RR = 0.78, 95% CI (0.68, 0.89), and P≤0.001], decrease incidence of renal and liver dysfunction [RR = 0.58, 95% CI (0.46, 0.73), and P≤0.001], and decrease cardiac dysfunction [RR = 0.41, 95% CI (0.18, 0.94), and P=0.035]. For the incidence of gastrointestinal adverse reactions [RR = 0.89, 95% CI (0.65, 1.21), and P=0.452], decreased platelet count [RR=0.49, 95% CI (0.18, 1.30), and P=0.150], and alopecia [RR = 1.01, 95% CI (0.89, 1.14), and P=0.879], these two groups showed no statistically significant differences. Conclusion. Kangai injection as an adjuvant method in combination with chemotherapy for treating Chinese breast cancer patients can improve their life quality and physical conditions and reduce the adverse reactions that result from chemotherapy. However, the present conclusion is only suitable for the Chinese population. The long-term, high-quality researches are required to further verify the above conclusions. [ABSTRACT FROM AUTHOR]

Monte Carlo (MC) simulations have been used to study the low-energy channeling of 10B and 11B ions along the [100] axis in Si crystal. MC simulations show that the critical angle ΨC ≈ 15.3(keV/E)1/2 (in degrees) for the channeling of isotopic 10B ions and ΨC=14.5(keV/E)1/2 (in degrees) for the channeling of isotopic 11B ions, where E is the incident energy. This means that (ΨC for 10B ions/ΨC for 11B ions)≈ (15.3/14.5)≈ (11/10)1/2. [ABSTRACT FROM AUTHOR]

Abstract: An Monte Carlo (MC) simulation program has been used to study ion mass dependence for the low energy channeling of natural- and pseudo-Ar ions in single-wall nanotubes. The MC simulations show that the channeling critical angle Ψ C obeys the (E)−1/2 and the (M 1)−1/2 rules, where E is the incident energy and M 1 is the ion mass. The reason for this may be that the motion of the channeled (or de-channeled) ions should be correlated with both the incident energy E and the incident momentum (2M 1 E)1/2, in order to obey the conservation of energy and momentum. [Copyright &y& Elsevier]

The magneto-optical Kerr effect of single-walled carbon nanotubes (SWNTs) film in the Terahertz region is theoretically studied by means of the Drude model. The calculation shows a new oscillation occurring near the plasma frequency as the origin of the magneto-optical Kerr effect for the single-walled nanotubes film. We propose that the amplitude of this near plasma frequency oscillation is directly proportional to the external magnetic field and its period increases with increasing cyclotron frequency. We consider these features of this oscillation of SWNTs are related to the Landau energy of SWNTs. The reflectivity and figure of merit (FOM) spectrum also reveal that this oscillation is the dominant mechanism for the magneto-optical Kerr effect of SWNTs film. Meanwhile, the shift and large enhancement of Kerr rotation under different external magnetic fields is explained. [Copyright &y& Elsevier]

Abstract: We have developed a mass- and charge-dependent equation to predict theoretical critical angles for ion channeling in carbon nanotubes. We focus M (ion mass) effects how to reduce Ze (ion nucleus charge) effects on ΨC (critical angles). As an instance, we give theoretical critical angels of He, Ne, Ar, Kr, Xe and Rn ion channeling in carbon nanotubes. We find that for (10,10) single-wall carbon nanotubes, ΨC (He)≈ ΨC (Ne)≈ ΨC (Ar)≈ ΨC (Kr)≈ ΨC (Xe)≈ ΨC (Rn)≈23.3(keV/E)1/2 deg. This is because (Z/M)1/2 ≈0.66[amu]−1/2. [ABSTRACT FROM AUTHOR]

Abstract: Lindhard proposed his classical equation for the critical channeling angle from consideration of conservation of transverse energy. We generalize those ideas via consideration of conservation of transverse momentum, and propose an improved equation. A dimensional analysis of the problem is also presented, and that analysis puts our arguments and results on a firm footing. [Copyright &y& Elsevier]

The effects of alloy surface composition and pre-adsorbed oxygen on the behaviors of H2O over Ni–Cr binary alloy surfaces were investigated by using the first-principles method. The surface energies and work functions for a series of Ni–Cr (111) alloy surfaces with different Cr concentrations were addressed to track the surface reactivities. An enhancement effect on the surface reactivity from Cr doping in the top-surface layer (TSL) of nickel substrates was identified. The locations of Cr in the TSL dramatically promoted exothermic adsorption of H2O and its decomposed products, including OH, O, and H. The calculated potential dissociation pathways further demonstrated that the successive dissociation of H2O molecules was substantially triggered in the presence of Cr doping in the TSL. By contrast, the Cr doping in the sub-surface layer hindered the dehydrogenation of H2O with a relatively higher energy barrier for OH dissociation. Moreover, with pre-adsorbed oxygen atoms closer to Cr, the first elementary step of H2O dissociation was easily fostered, whereas the OH dissociation was hindered. The Cr doping and O pre-adsorption accelerated the dissociation of H2O, which plays a critical role in the initial oxidation of nickel-based alloys in water- or oxygen-bearing environments. [ABSTRACT FROM AUTHOR]

The Loess Plateau region is characterized by fragmented habitats and ecological vulnerability. Analyzing the changes in land use and ecological risk within the region is of great significance for promoting high-quality development of the Loess Plateau. The study utilized land use data from 2000, 2010, and 2020 in the Loess Plateau region to assess the spatio-temporal variation in land use patterns and landscape ecological risks, aiming to provide valuable references and decision support for ecological risk management and sustainable development in the area. The results indicated that the main land use types in the region are grassland and cropland. From 2000 to 2020, forest, grassland, and water areas increased by 1.39 × 106, 6.25 × 105, and 7.09 × 104 ha, respectively. The impervious area increased rapidly, growing from 9.77 × 104 ha in 2000 to 1.85 × 106 ha in 2020. The cropland decreased by 1.82 × 106 ha from 2000 to 2020, with 4.61 × 105, 4.95 × 106, and 8.91 × 105 ha of cropland converted to forest, grassland, and impervious area, respectively. The fragmentation of the ecological landscape in the region has decreased, and the diversity and richness of landscape types have increased. The fragmentation of cropland, forest, and grassland has decreased, and landscape patches have become more concentrated. High-value areas of landscape ecological risk in the region show a trend of continuous aggregation, altering the dispersion pattern of high-risk areas. Currently, high-risk areas of landscape ecology in the Loess Plateau region are mainly concentrated in northern Shaanxi and some areas along the Yellow River, such as Yulin, Yan'an, Ordos, and others. Currently, the ecological environment remains a bottleneck constraining the high-quality development of the Loess Plateau. It is necessary to persist in coordinated governance and ecological engineering construction, and improving the quality of ecological environment is a prerequisite for consolidating the social foundation and leading the high-quality development of the ecological industry on the Loess Plateau. [ABSTRACT FROM AUTHOR]

Flexible and wearable supercapacitors (SCs) have received extensive attention due to their promising applications in wearable electronics. Previous efforts have been mainly devoted to fabricate electrode materials with high surface areas, including activated carbon through carbonizing natural fibers at high temperature. This methodology however frequently disintegrates the fibrous structures and fails to take full advantage of the intrinsic and foremost feature of the fibers as fabrics. Herein we proposed one alternative strategy to enhance SC performance through utilizing natural hollow Calotropis gigantea fibers (CGFs) with hydrophobic surfaces to confine conductive polymer of polypyrrole (PPy) both outside and inside of the fiber lumen. The in situ electrodeposited PPy enabled a full contact between the electrode material and electrolyte, enlarged the electrolyte accessible area and spurred the capacitive performance of the SC, which demonstrated a significantly improved specific capacitance of 785.78 mF cm −2 at a current density of 4 mA cm −2 compared with the 648.44 mF cm −2 of SCs without the fibers (a 21.2% increase). The harness of confinement effect could potentially expand to be a general way to rationally design synthetic fibers with customized inner and outer diameter ratios, superficial hydrophobic/hydrophilic properties to realize optimum electrochemical performance for SCs. [ABSTRACT FROM AUTHOR]

Paraquat is a toxic chemical that is widely used as an herbicide (plant killer), primarily for weed and grass control. Recently, kinase inhibitors have shown great potential against paraquat-mediated toxicological effects and, specifically, the c-Jun N-terminal protein kinase ( JNK) was found as a new and promising target for relieving the paraquat toxicity. Here, we developed a statistical molecular identification protocol that systematically profiles a variety of existing kinase inhibitors against JNK. A consensus molecular docking strategy was developed to examine the binding behavior of inhibitor candidates, from which top-8 hit compounds were selected and tested; several compounds were found to show high or moderate inhibitory potency against JNK with IC50 values at nanomolar level, which are comparable to the sophisticated JNK inhibitor SP600125. We also performed atomistic molecular dynamics simulations and post binding free energy analyses to dissect the structural basis, energetic property, and biological implication underlying the intermolecular interaction of JNK kinase domain with these promising compounds, highlighting the complicated interaction pattern between the kinase and potent hit compounds. [ABSTRACT FROM AUTHOR]

The effects of fluorine adsorption on the surface segregation behaviors of chromium in nickel-based alloys are systematically investigated by selecting three typical low-index Cr-doped Ni (111), (100), and (110) surfaces based on the first-principles calculations. The Cr doped in the nickel substrate is identified to possess a local trapping effect for fluorine in the full space and contributes to the more exothermic adsorption of fluorine. In turn, the chemisorption of fluorine on the Cr-doped Ni surfaces can dramatically incur the preferential top-surface segregation for Cr from nickel bulk. The increased adsorption energy of fluorine on Cr-doped Ni surfaces compensates for the larger surface energy of Cr relative to Ni. The strong F-Cr bonding from the deeper hybrid state of F 2p-Cr 3d helps to release strain energy caused by atomic size mismatch. At higher fluorine coverage, the driving force for Cr to segregate at nickel surfaces is significantly increased, as the fluorine starts to agglomerate in the vicinity of Cr. Such chemisorption-induced surface abnormal segregation of Cr to the top-most surface plays a critical role in the preferential dealloying of Cr at the early-stage corrosion of non-passivated nickel-based alloys in molten fluoride salts. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes (CNTs) have been proposed as one of the most promising materials for nanoelectromechanical systems. Taking advantage of the long range van der Waals interactions between inner walls of CNTs, the tubes have bistable states: the cylindrical CNTs and the flattened CNTs. As an electrical switch, CNT can be switched between ON and OFF states because of their different conductivities. We focus on this mechanical behavior by radial compressing cylindrical CNTs into the flattened CNTs. We show that the radial compressive elastic modulus of CNTs is exponential decay with the tube radius. With the temperature increases, the flattened CNTs can expand to the cylindrical state again. The critical temperature increases with the tube radius. Taking the advantage of the bistability of CNTs, it can be used as nanoswitch, nanosensors and it also can control fluid flow. [Copyright &y& Elsevier]

The construction of frame wavelets with compact supports is a meaningful problem in wavelet analysis. In particular, it is a hard work to construct the frame wavelets with explicit analytic forms. For a given n × n real expansive matrix A, the frame-sets with respect to A are a family of sets in R n . Based on the frame-sets, a class of high-dimensional frame wavelets with analytic forms are constructed, which can be non-bandlimited, or even compactly supported. As an application, the construction is illustrated by several examples, in which some new frame wavelets with compact supports are constructed. Moreover, since the main result of this paper is about general dilation matrices, in the examples we present a family of frame wavelets associated with some non-integer dilation matrices that is meaningful in computational geometry. [ABSTRACT FROM AUTHOR]

For long-span cable-stayed bridges, cables are one of the most important components to resist various actions. With the application of structural health monitoring technique, real-time recording of cable forces is achieved, and hence, the warning system on cable anomaly established. However, it is still difficult and there are challenges to conduct the warning system effectively, especially due to the phenomena of false alarm or omission. A practical reason is the warning index's sensitivity to the ambient environment. Temperature variations, for instance, usually disturb the force-based cable anomaly warning and result in the false evaluation of structural condition. In view of eliminating the effects of environmental temperature, cointegration, a statistical concept from econometrics, is employed in cable anomaly warning studies. An approach that extracts warning index by linear combination of two non-stationary time series using the cointegration algorithm is developed in order to produce a more stationary cointegrated residual series (warning index series). The calculated stationary relationship between two time series is insensitive to the influence of environmental temperature and is capable of cable anomaly warning. Specifically, the framework of the cable anomaly warning system is first proposed. Subsequently, time-series test methods are introduced to check the non-stationary order and calculate the cointegration parameters of measured cable forces and environmental temperature. The computed cointegrated residual series is fed into statistical analysis as a warning index and the procedure of cable anomaly warning under the influence of environmental temperature is illustrated in detail. Finally, a case study for a cable-stayed bridge is demonstrated with results and discussions. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) has from ancient times been applied in China for the treatment of breast cancer with its own unique theoretical system. Sanhuang decoction composed of astragalus membranaceus, prepared rhubarb, and rhizoma curcumae longae has traditionally been used for antioxidant stress, inflammatory reaction, and angiogenesis. However, the role and mechanism of Sanhuang decoction in breast cancer remains unknown. The present study demonstrated the antitumor activity of Sanhuang decoction against breast cancer xenografts in nude mice. Notably, Sanhuang decoction promoted severe necrosis and induced cell death. In addition, Sanhuang decoction obviously regulated the inflammation and oxidative stress. Despite these, Sanhuang decoction could increase the expression of Nrf2. Moreover, si‐Nrf2 exhibited the opposite effects compared with the Sanhuang decoction treatment group and reversed the antibreast cancer role of Sanhuang decoction. Further, Sanhuang decoction remarkably suppressed the expression of PI3K/AKT/mTOR signaling pathway. Taken together, Sanhuang decoction was firstly evaluated to possess potent antibreast cancer effect in vivo through regulation of inflammation and oxidative stress accomplished by up‐regulation of Nrf2 via PI3K/AKT/mTOR signaling pathway and Sanhuang decoction might be a powerful candidate formula for antibreast cancer. [ABSTRACT FROM AUTHOR]

• AFRP-to-concrete interfacial behavior attacked by underground water was examined. • Single-lap shear tests and pull-off bond tests were carried out. • Specimens were immersed in water, chloride and sulfate solutions up to 300 days. This study explores long-term performance of AFRP-to-concrete interfacial behavior when subjected to underground water. Tensile coupon samples of AFRP sheets and structural adhesive, pull-off bond specimens and single-lap shear specimens were prepared and immersed in water, chloride, and sulfate solutions for up to 300 days. Test results showed that mechanical properties of the structural adhesive were significantly degraded under the three environmental conditions. Failure modes of both pull-off bond specimens and single-lap shear specimens gradually changed from concrete substrate failure to adhesive-concrete interfacial debonding after exposure. After 300 days, the pull-off strength, shear bond strength and interfacial fracture energy decreased by 14.8 %-34.2 %, whereas the effective bond length and bond stiffness increased. Water immersion exhibited the most severe detrimental effect on the bond behavior between AFRP and concrete in comparison with chloride and sulfate attacks. Bond-slip relationship between the AFRP and concrete was derived based on the slip distribution on the AFRP. The peak bond stress, corresponding slip and maximum slip of the bond-slip curves remarkably declined after exposure for 300 days. [ABSTRACT FROM AUTHOR]

Adsorption and diffusion behaviors of fluorine on Cr-doped Ni(111) surface are investigated by using first-principles simulation. It shows that the Cr in the Cr-doped Ni(111) surface serve a trap site for fluorine with adsorption energy 3.52 eV, which is 1.04 eV higher than that on Ni(111) surface. Moreover, the Cr atom is pulled out the surface for 0.41 Å after the fluorine adsorption, much higher than that on Ni(111) surface. Further diffusion behaviors analysis confirms the conclusion because the fluorine diffusion from neighbored sites onto the Cr top site is an energy barrierless process. Detailed electronic structure analysis shows that a deeper hybrid state of F 2 p -Cr 3 d indicates a strong F Cr interaction. The Ni Cr bond is elongated and weakened due to the new formed F Cr bonding. Our results help to understanding the basic fluorine-induced initial corrosion mechanism for Ni-based alloy in molten salt environment. [ABSTRACT FROM AUTHOR]

Ultrathin uniform BP nanosheets with lateral dimensions of up to several tens of micrometers were prepared via a small molecule–assisted liquid phase exfoliation method, which exhibited attractive electron accepting abilities from photosensitizers and was thus promising in diverse applications such as photocatalysis and photovoltaics. [ABSTRACT FROM AUTHOR]

The high-throughput production of the eco-friendly MIL-88A(Fe) was achieved under mild reaction conditions with normal pressure and temperature. The as-prepared MIL-88A(Fe) exhibited efficient photo-Fenton catalytic ofloxacin (OFL) degradation upon visible light irradiation with good stability and reusability. The OFL (20.0 mg/L) was completely degraded within 50 min under visible light with the aid of MIL-88A(Fe) (0.25 g/L) and H 2 O 2 (1.0 mL/L) in aqueous solution (pH = 7.0). The hydroxyl radicals (·OH) are the main active species during the photo-Fenton oxidation process. Meanwhile, the degradation intermediates and the corresponding degradation pathways were identified and proposed with the aid of both ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) and density functional theory (DFT) calculations. Finally, the degradation product library was firstly established to identify intermediate transformation products (TPs) with their variation of concentration, and their corresponding toxicologic activities were assessed via Toxtree and T.E.S.T software as well. Finally, the MIL-88A is efficient and stable with four cycles' catalysis operations, demonstrating good potential for water treatment. • MIL-88A(Fe) exhibited efficient photo-Fenton catalytic degradation of OFL. • The degradation product library was established to identify intermediates. • The lifetime of formed intermediates was monitored. • The toxicity of OFL and intermediates were evaluated. • The OFL degradation pathways were proposed with UPLC-Q-TOF-MS and DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: The Monte Carlo simulation program has been used to study low energy channeling in the single-wall nanotube and its rope, in comparisons between beam sizes and between light (He) and heavy (Ar) ions. The simulation mainly shows that the critical angle Ψ C =48 E −1/2 (E is incident energy) for the He (light) ion channeling but Ψ C =18 E −1/2 for the Ar (heavy) ion channeling, in the (17,0) zigzag single-wall nanotube. Thus, it might be found in the simulation that Ψ C strongly depends on the ion mass. [Copyright &y& Elsevier]

Considering the Coulomb-hydrodynamic explosion induced by the interaction of a deuterium cluster target with ultra-intensity femtosecond laser, the mechanism which generates energetic deuterium nuclei for the fusion has been analyzed. The formulas for expansions of the deuterium ion cluster, which are driven by the Coulomb-hydrodynamic explosion, are proposed. Hence the kinetic energies of deuterium nuclei and the expansion time of deuterium ion cluster have been estimated. [ABSTRACT FROM AUTHOR]

Abstract: The isospin dependence of the nucleon effective mass is investigated in the framework of the Dirac Brueckner–Hartree–Fock (DBHF) approach. The definition of nucleon scalar and vector effective masses in the relativistic approach is clarified. Only the vector effective mass is the quantity related to the empirical value extracted from the analysis in the non-relativistic shell and optical potentials. In the relativistic mean field theory, where the nucleon scalar and vector potentials are both energy independent, the neutron vector potential is stronger than that of proton in the neutron-rich nuclear matter, which produces a smaller neutron vector effective mass than that of proton. It is pointed out that the energy dependence of nucleon potentials has to be considered in the analysis of the isospin dependence of the nucleon effective mass. In the DBHF the neutron vector effective mass is larger than that of proton once the energy dependence of nucleon potentials is considered. The results are consistent with the analysis of phenomenological isospin dependent optical potentials. [Copyright &y& Elsevier]