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Cancer is the leading cause of death worldwide. Early detection of cancer can lower the mortality of all types of cancer; however, effective early-detection biomarkers are lacking for most types of cancers. DNA methylation has always been a major target of interest because DNA methylation usually occurs before other detectable genetic changes. While investigating the common features of cancer using a novel guide positioning sequencing for DNA methylation, a series of universal cancer only markers (UCOMs) have emerged as strong candidates for effective and accurate early detection of cancer. While the clinical value of current cancer biomarkers is diminished by low sensitivity and/or low specificity, the unique characteristics of UCOMs ensure clinically meaningful results. Validation of the clinical potential of UCOMs in lung, cervical, endometrial, and urothelial cancers further supports the application of UCOMs in multiple cancer types and various clinical scenarios. In fact, the applications of UCOMs are currently under active investigation with further evaluation in the early detection of cancer, auxiliary diagnosis, treatment efficacy, and recurrence monitoring. The molecular mechanisms by which UCOMs detect cancers are the next important topics to be investigated. The application of UCOMs in real-world scenarios also requires implementation and refinement. [ABSTRACT FROM AUTHOR]

Based on first-principles calculations, the electronic, magnetic, and topological characters of manganese (Mn) doped topological insulator Bi2Te3 were investigated. The Mn substitutionally doped Bi2Te3, where Mn atoms tend to be uniformly distributed, was shown to be p-type ferromagnetic, arising from hole-mediated Ruderman-Kittel-Kasuya-Yosida interaction. Mn doping leads to an intrinsic band splitting at Γ point, which is substantially different from that of nonmagnetic dopant. The topological surface state of Bi2Te3 is indeed gapped by Mn doping; however, the bulk conductance limits the appearance of an insulating state. Moreover, the n-type doping behavior of Bi2Te3 is derived from Mn entering into the van der Waals gap of Bi2Te3. [ABSTRACT FROM AUTHOR]

To promote the full combustion efficiency of a body cremation furnace during cremation, the temperature and velocity of cremation furnace in the process of body combustion are simulated by finite element model. Firstly, the simplified finite element analysis model of cremation furnace and its finite element software is introduced in this study, and then the flow model, heat transfer model, and combustion model needed in the heat transfer process are described. According to the requirements of the finite element model, the mesh generation process of the cremation furnace model and the numerical solution method are presented. Finally, the model used in this study is verified by the test and simulation results. The results show that the method is reliable. Besides, the design parameters of the temperature part and the combustion speed part of the furnace under six different working conditions are analyzed to further optimize the structure of the furnace. The results of this study provide a good theoretical basis for cremation equipment and promote the development of China's cremation industry. [ABSTRACT FROM AUTHOR]

Density functional theory calculations are employed to systematically investigate the trend of hydrogen evolution reaction (HER) performance of oxygen-terminated MXenes. By studying 30 transition-metal carbides and 30 transition-metal nitrides, Mn+1CnO2 and Mn+1NnO2 (M = Sc, Cr, Hf, Mo, Nb, Ta, Ti, V, W, Zr; n = 1, 2, 3), the tendency of oxygen desorption after hydrogen adsorption is elucidated to play a key role in HER performance of oxygen-terminated MXenes. On the basis of these observations, we propose a suitable HER descriptor, oxygen vacancy formation energy (Ef), which scales linearly with the adsorption free energy of hydrogen, ΔGH. In addition, this new descriptor is linearly correlated with the lithium binding strength on oxygen-terminated MXenes. Therefore, Ef is a universal descriptor for identifying the trend of adsorption processes where adsorbed species donate electrons to oxygen-terminated MXenes. This work provides a general guideline for large-scale screening of promising MXene-based materials for energy storage and conversion. [ABSTRACT FROM AUTHOR]

Barlowite Cu4(OH)6FBr is a newly found mineral containing Cu2+ kagome planes. Despite similarities in many aspects to herbertsmithite Cu3Zn(OH)6Cl2, the well-known quantum spin liquid (QSL) candidate, intrinsic barlowite turns out not to be a QSL, possibly due to the presence of Cu2+ ions in between kagome planes that induce interkagome magnetic interaction [Phys. Rev. Lett. 113, 227203 (2014)]. Using first-principles calculation, we systematically study the feasibility of selective substitution of the interkagome Cu ions with isovalent nonmagnetic ions as a function of ion concentration up to the stoichiometric limit. Unlike previous speculation of using larger dopants, such as Cd2+ and Ca2+, we identify the most ideal stoichiometric doping elements to be Mg and Zn in forming Cu3Mg(OH)6FBr and Cu3Zn(OH)6FBr with the highest site selectivity and smallest lattice distortion. The equilibrium antisite disorder in Mg/Zn-doped barlowite is estimated to be one order of magnitude lower than that in herbertsmithite. The single-electron band structure and orbital component analysis show that the proposed selective doping effectively mitigates the difference between barlowite and herbertsmithite. [ABSTRACT FROM AUTHOR]

Grain boundaries (GBs) of hexagonalboron nitride (h-BN) grown on Cu(111) were investigated by scanningtunneling microscopy/spectroscopy (STM/STS). The first experimentalevidence of the GBs composed of square-octagon pairs (4|8 GBs) wasgiven, together with those containing pentagon-heptagon pairs (5|7GBs). Two types of GBs were found to exhibit significantly differentelectronic properties, where the band gap of the 5|7 GB was dramaticallydecreased as compared with that of the 4|8 GB, consistent with ourobtained result from density functional theory (DFT) calculations.Moreover, the present work may provide a possibility of tuning theinert electronic property of h-BN via grain boundary engineering. [ABSTRACT FROM AUTHOR]

The two-dimensional (2D) transitionmetal dichalcogenides (TMDC, of generic formula MX2) monolayerdisplays the “triple-decker” structure with the chemicalbond organization much more complex than in well-studied monatomiclayers of graphene or boron nitride. Accordingly, the makeup of the dislocationsin TMDC permits chemical variability, depending sensitively on theequilibrium with the environment. In particular, first-principlescalculations show that dislocations state can be switched to highlymobile, profoundly changing the lattice relaxation and leading tosuperplastic behavior. With 2D MoS2as an example, we constructfull map for dislocation dynamics, at different chemical potentials,for both the M- and X-oriented dislocations. Depending on the structureof the migrating dislocation, two different dynamic mechanisms arerevealed: either the direct rebonding (RB) mechanism where only asingle metal atom shifts slightly, or generalized Stone–Wales(SWg) rotation in which several atoms undergo significantdisplacements. The migration barriers for RB mechanism can be 2–4times lower than for the SWg. Our analyses show that withina range of chemical potentials, highly mobile dislocations could atthe same time be thermodynamically favored, that is statisticallydominating the overall material property. This demonstrates remarkablepossibility of changing material basic property such as plasticityby changing elemental chemical potentials of the environment. [ABSTRACT FROM AUTHOR]

Developmentally regulated endothelial cell locus-1 (Del1) is an embryonic angiogenic factor expressed in early embryonic endothelial cells, but recently has been found to be expressed in some forms of cancers including colon and breast cancers, and melanoma, and human cancer cell lines. Overexpression of Del1 accelerates tumor growth by enhancing vascular formation, implying Del1 may be a potential target for anti-angiogenic cancer therapy. The study aims to investigate whether downregulation of Del1 could inhibit the growth of tumors established in nude Balb/c mice by subcutaneous implantation of human LS-174T colon cancer cells. The shRNA expression vectors targeting human Del1, and vascular endothelial growth factor (VEGF) were constructed. Gene transfection of Del1-shRNA downregulated expression of Del1 in LS-174T cells in vivo and in vitro, but did not alter the proliferative or survival properties of cells in vitro. Gene transfection of VEGF-shRNA downregulated expression of both VEGF and Del1 in LS-174T cells in vivo and in vitro. Both Del1-shRNA and VEGF-shRNA gene therapies exhibited anti-tumor activities and they also showed a synergistic effect in suppressing growth of colon tumors by anti-angiogenesis and anti-proliferation. Although further investigation to clarify the mechanisms explaining the role of Del1 in tumor growth, and the interaction between VEGF and Del1, is required, the results indicate that downregulation of Del1 presents a potent therapeutic strategy to combat colon cancer. [ABSTRACT FROM AUTHOR]

The novel crumb rubber (CR)/styrene-butadiene-styrene (SBS) composite modified asphalt has shown through various researches to have a better engineering performance than many commonly used modified asphalts. On the basis of the optimal preparation scheme of composite asphalt rubber, dynamic shear rheology (DSR) test was conducted to evaluate the rheological property of the modified asphalt, and performance tests were conducted on the composite asphalt rubber mixture. The influence of gradation type and anti-rutting agent on its mixture's performance improvement was then summarized. Three different micro analysis test methods were used to observe the distribution and morphological changes of the modifier in the asphalt. Furthermore, the subsequent physical and chemical reactions that occurred between asphalt and modifier during the modification process were also studied. The results showed that the viscosity of composite asphalt rubber decreased as shear time increased. The rutting factor and the creep rate of the composite asphalt rubber were about 77.9% and 4.4%, respectively, both higher than that of the asphalt rubber. Meanwhile, when compared with the anti-rutting agent used in practical engineering, the high-temperature performance of HXR-I (anti-rutting agent) was improved by 45.3%, the low-temperature performance was improved by 6.3%, and the water stability was improved by 17.8%. The microscopic test results showed that the rubber particles in the composite asphalt rubber swelled and were wrapped by asphalt and distributed around the aggregate. At the same time, it also illustrated that adding anti-rutting agent can improve the performance of the composite asphalt rubber in an effective way, which could adequately meet the required low-temperature performance, thus expanding its application in road engineering. [ABSTRACT FROM AUTHOR]

Our first-principles calculations indicate the possibility of preparing spin-polarized scanning tunneling microscopy (SP-STM) probes from Fe-doped capped carbon nanotubes (CNTs). The structural stability, magnetic moment, and electronic property of hybrid systems are found to depend on the Fe adsorption site, which is attributed to the hybridization between Fe 3d and C 2p orbitals. The CNTs with Fe atoms adsorbed at the tip-top are demonstrated to be promising candidates for the SP-STM probe, with a high spin polarization leading to a completely spin-polarized current at lower voltages. In contrast, the CNTs encapsulating Fe atom are basically nonmagnetic, and thus useless for the SP-STM probe application in nature. [ABSTRACT FROM AUTHOR]

To investigate the salt-release performance of salt-storage aggregates, salt-storage aggregates were prepared using magnesium oxychloride cement as a carrier through the addition of chloride salts and sustained-release agents. The different types of salt-storage aggregates were compared and selected through compressive strength and immersion conductivity tests. In addition, the salt-release performance of salt-storage asphalt mixtures was investigated by immersion conductivity tests and simulated rain erosion tests. The results indicate that as a sustained-release agent, polyethylene glycol has a certain adverse effect on the compressive strength of salt-storage aggregates, whereas glycerol has an enhancing influence during 28 days of standard curing conditions. The salt-storage aggregates with sustainedrelease agents show a good sustained-release effect and a relatively stable conductivity growth. Compared with polyethylene glycol, glycerol attains a better sustained-release effect on salt-storage aggregates with CaCl2 as a snowmelting agent. Under short-term immersion conditions, the conductivity of salt-storage asphalt mixture specimens increases rapidly with prolonged immersion. Under long-term immersion conditions, the conductivity changes under different replacement rates show two stages, namely, the early stage featuring a rapid increase and the later stage showing a gradual trend. The salt-dissolved regularity of salt-storage asphalt mixture conforms to the logarithmic model. After 5 years of equivalent rainwater erosion, the salt-storage asphalt mixture can still release salt. The study provides a good reference for the production and application of salt-storage aggregate in road maintenance. [ABSTRACT FROM AUTHOR]

Differential pulse cathodic stripping voltammetry was used to determine pesticide mctsulfuron-mclhyl on a suspended mercury electrode. Specific experimental parameters, such as the pH of Britlon-Rohinson buffer, accumulation time, accumulation potential, and initial potential were optimized. The results show that a typical reduction peak appeared when pH was 2.0 -4.0 arul initial potential ranged from -0.75 to -1.0 V. To obtain the stripping signal of the best reduction peak, it is determined that the best pH was 2.0. The detection limit of the method was only 0.04 mg/L, and it had good selectivity and high accuracy, so the method has high sensitivity. In the analysis of actual drinking water, the recovery rate of metsulfuron-meth-yl could reach 93% - 101%. [ABSTRACT FROM AUTHOR]

At present, the single-point observation method is not able to effectively monitor the overall settlement of the target surface of an embankment. The 3D laser scanning technology was, therefore, introduced to help solve this problem. In this study, the overall settlement of the Shi'an highway extended embankments were dynamically monitored and a series of point cloud data were obtained by 3D laser scanning. Due to the characteristics of point cloud data, the grid analysis and interpolation method in MATLAB were proposed for the analysis, so as to obtain the overall settlement displacements of the extension embankment. Furthermore, the reliability and accuracy of the 3D laser scanning were verified through comparison with the single-point observation, and the results are as follows: during the embankment extension construction process, the monitoring accuracy was improved by 25.8% at least when compared to the single-point observation method; during the asphalt pavement construction, the maximum settlement of single-point monitoring and the 3D laser scanning method recorded similar values of 1.6 mm and less than 2 mm, respectively; throughout the course of the 3-year post-construction settlement observation, the monthly settlement rate was maintained at an insignificant 0.01-0.09 mm/month for the single-point monitoring, and a similar rate of less than 0.05 mm for the 3D laser scanning method. These results show that the 3D laser scanning could reflect the overall settlement dynamics much better, and that combined with its advantages of fast and accurate observation, could be used to evaluate the settlements of new and old embankments in extension projects. [ABSTRACT FROM AUTHOR]

Weshow that nanoribbons of boron- and nitrogen-substituted graphenecan be used as efficient electrocatalysts for the oxygen reductionreaction (ORR). Optimally doped graphene nanoribbons made into three-dimensionalporous constructs exhibit the highest onset and half-wave potentialsamong the reported metal-free catalysts for this reaction and showsuperior performance compared to commercial Pt/C catalyst. Furthermore,this catalyst possesses high kinetic current density and four-electrontransfer pathway with low hydrogen peroxide yield during the reaction.First-principles calculations suggest that such excellent electrocatalyticproperties originate from the abundant edges of boron- and nitrogen-codopedgraphene nanoribbons, which significantly reduce the energy barriersof the rate-determining steps of the ORR reaction. [ABSTRACT FROM AUTHOR]

Designing materials for desired thermal conduction can be achieved via extended defects. We theoretically demonstrate the concept by investigating thermal transport in graphene nanoribbons (GNRs) with the extended line defects observed by recent experiments. Our nonequilibrium Green's function study excluding phonon-phonon interactions finds that thermal conductance can be tuned over wide ranges (more than 50% at room temperature), by controlling the orientation and the bond configuration of the embedded extended defect. Further transmission analysis reveals that the thermal-conduction tuning is attributed to two fundamentally different mechanisms, via modifying the phonon dispersion and/or tailoring the strength of defect scattering. The finding, applicable to other materials, provides useful guidance for designing materials with desired thermal conduction. [ABSTRACT FROM AUTHOR]

The development of integrated circuits urgently demands improved understanding of interfacial thermal transport at the nanoscale. We report a systematical nonequilibrium Green's function study on thermal transport in a class of experimentally available carbon-based nanostructures, partially unzipped carbon nanotubes (PUCNTs), where unusual interfacial thermal transport behaviors are revealed. We find that thermal conductance of PUCNTs shows a perfect linear dependence on the width of the unzipped part and an exponential decay (to a finite value) with the length of the unzipped part. The exponential length dependence observed at interfaces is a pure quantum phenomenon without classical counterpart. The improved understanding of nanoscale thermal transport can find applications in designing high-performance thermal management and/or thermoelectric nanodevices. [ABSTRACT FROM AUTHOR]

The article presents a research on spontaneous self-intercalation of copper atoms into transition metal dichalcogenides. Topics discussed include Intercalated transition metal dichalcogenides (TMDs) have attracted substantial interest due to their exciting electronic properties; develop a strategy to synthesize Cu species–intercalated layered TMD compounds; and area of catalysis and electrochemical energy storage.

Vertically stacked van der Waals heterostructures composed of compositionally different two-dimensional atomic layers give rise to interesting properties due to substantial interactions between the layers. However, these interactions can be easily obscured by the twisting of atomic layers or cross-contamination introduced by transfer processes, rendering their experimental demonstration challenging. Here, we explore the electronic structure and its strain dependence of stacked MoSe2/WSe2 heterostructures directly synthesized by chemical vapor deposition, which unambiguously reveal strong electronic coupling between the atomic layers. The direct and indirect band gaps (1.48 and 1.28 eV) of the heterostructures are measured to be lower than the band gaps of individual MoSe2 (1.50 eV) and WSe2 (1.60 eV) layers. Photoluminescence measurements further show that both the direct and indirect band gaps undergo redshifts with applied tensile strain to the heterostructures, with the change of the indirect gap being particularly more sensitive to strain. This demonstration of strain engineering in van der Waals heterostructures opens a new route toward fabricating flexible electronics. [ABSTRACT FROM AUTHOR]

The practical recycling of carbon dioxide (CO2) by the electrochemical reduction route requires an active, stable, and affordable catalyst system. Although noble metals such as gold and silver have been demonstrated to reduce CO2 into carbon monoxide (CO) efficiently, they suffer from poor durability and scarcity. Here we report three-dimensional (3D) graphene foam incorporated with nitrogen defects as a metal-free catalyst for CO2 reduction. The nitrogen-doped 3D graphene foam requires negligible onset overpotential (-0.19 V) for CO formation, and it exhibits superior activity over Au and Ag, achieving similar maximum Faradaic efficiency for CO production (~85%) at a lower overpotential (-0.47 V) and better stability for at least 5 h. The dependence of catalytic activity on N-defect structures is unraveled by systematic experimental investigations. Indeed, the density functional theory calculations confirm pyridinic N as the most active site for CO2 reduction, consistent with experimental results. [ABSTRACT FROM AUTHOR]