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The main hallmark of myocardial substrate metabolism in cardiac hypertrophy or heart failure is a shift from fatty acid oxidation to greater reliance on glycolysis. However, the close correlation between glycolysis and fatty acid oxidation and underlying mechanism by which causes cardiac pathological remodelling remain unclear. We confirm that KLF7 simultaneously targets the rate-limiting enzyme of glycolysis, phosphofructokinase-1, liver, and long-chain acyl-CoA dehydrogenase, a key enzyme for fatty acid oxidation. Cardiac-specific knockout and overexpression KLF7 induce adult concentric hypertrophy and infant eccentric hypertrophy by regulating glycolysis and fatty acid oxidation fluxes in male mice, respectively. Furthermore, cardiac-specific knockdown phosphofructokinase-1, liver or overexpression long-chain acyl-CoA dehydrogenase partially rescues the cardiac hypertrophy in adult male KLF7 deficient mice. Here we show that the KLF7/PFKL/ACADL axis is a critical regulatory mechanism and may provide insight into viable therapeutic concepts aimed at the modulation of cardiac metabolic balance in hypertrophied and failing heart.

Odd-parity superconductivity is recognized as a key ingredient to realize topological superconductivity. In Bi2Se3-based bulk topological superconductors, the odd-parity pairing, which spontaneously breaks the threefold rotational symmetry of the crystal, leading to a subsidiary nematic order, was discovered. The nematic superconducting state can be identified by thermodynamic measurement, nuclear magnetic resonance measurement, ac- $$\chi$$ measurement, magnetic torque measurement or magnetoresistance measurement. Here, the single crystal of topological superconductor Pd $$_x$$ Bi2Te3 was grown. Its upper critical fields were obtained by magnetoresistance measurement in various magnetic field orientations parallel to the basal plane. The in-plane upper critical fields clearly demonstrate a twofold symmetry that break the threefold crystal symmetry. This provides experimental evidence that Pd-doped Bi2Te3 is a nematic topological superconductor similar to the Cu-, Sr-, and Nb-doped Bi2Se3.

The antiferromagnetic topological insulator has attracted lots of attention recently, as its intrinsic magnetism and topological property make it a potential material to realize the quantum anomalous Hall effect at relative high temperature. Until now, only MnBi2Te4 is predicted and grown successfully. The other MB2T4-family materials predicted (MB2T4: M = transition metal or rare earth element, B = Bi or Sb, T = Te, Se, or S) with not only antiferromagnetic topological property but also rich and exotic topological quantum states and dynamically stable (or metastable) structure have not been realized on experiment completely. Here, MnBi2Te4 single crystals have been grown successfully by us. It shows typical antiferromagnetic character with Neel temperature of 24.5 K and a spin-flop transition at H ≈ 35,000 Oe, 1.8 K. In order to obtain the other members of MB2T4-family materials, it is necessary to understand the growth mode of MnBi2Te4. Its growth mode may be the layer-inserting growth mode based on symmetry, which is supported by our X-ray photoelectron spectroscopy (XPS) result, as the intrinsic chemical states of Mn and Te of MnBi2Te4 are the same with those of inserting material α-MnTe. Understanding the growth mode of MnBi2Te4 can help us to grow the other members of MB2T4-family materials.

The Pb39Bi25Sn36 alloy was directionally solidified at varied withdrawal rates followed by quenching. From metallographic observation, composition analysis and differential scanning calorimetry (DSC) analysis, the solidification sequence of Pb39Bi25Sn36 alloy was characterized. The Sn-dendrite is observed as the primary phase during solidification, followed by the β(Pb7 Bi3 )/Sn divorced eutectic. At lower temperatures, the β(Pb7Bi3 )/Sn binary eutectic is formed in the interdendritic region. However, the quasi-peritectic reaction [L+α-Pb→β(Pb7 Bi3 )+Sn] does not occur as the prediction based on ternary phase diagram analysis, which can be attributed to the unequilibrium solidfication condition. Moreover, the as-cast microstructure is significantly refined with the increasing withdrawal rates. The quenched sample only exhibits the lamellar structure of Sn, β(Pb7Bi3) and Bi phases. The results can provide instructions to optimize the as-cast microstructure of ternary alloys with quasi-peritectic reaction.

Active immunization is a crucial colony-level pathogen defense to improve the survival of eusocial termites, which limits the lethal effect of biopesticides for termite control. Here, we report a possible strategy for RNAi-mediated metabolic disorders, which causes reduction in insect pathogen defense and might facilitate the foundation of nontoxic and sustainable pest control methods. Isocitrate dehydrogenase (IDH) was significantly upregulated by active immunization in termites, but its regulatory mechanism has yet to be well understood. We found that dsIDH-injected termites exhibited significantly reduced IDH at mRNA and protein levels and altered levels of isocitrate and NADH, indicating the impaired NAD+-IDH reaction. IDH-silenced termites displayed metabolic disorders, which was implied by significant changes in several metabolites from the carbohydrates and amino acids. When grooming toward fungus-exposed termites, IDH-silenced nestmates showed a significant upregulation of four apoptosis-related genes and caspase 3 activity, and hence the significantly increased rate of apoptosis. These physiological changes led to more apoptotic cell death in different body parts of the nestmates. In particular, more apoptotic cells increased disease susceptibility of the nestmates as revealed by growth of the significantly increased number of colony-forming units from dissected gut contents. Furthermore, the IDH-silenced nestmates exhibited lower antifungal activity and higher mortality, suggesting that IDH downregulation disrupted active immunization against fungal pathogens in termites. These findings illustrated the metabolic regulation of active immunization and provide a sound foundation for enhancing the impact of biopesticides by reducing the pathogen defense of hosts.

Bone metastasis is one of the most serious complications in lung cancer patients. MicroRNAs (miRNAs) play important roles in tumour development, progression and metastasis. A previous study showed that miR-106a is highly expressed in the tissues of lung adenocarcinoma with bone metastasis, but its mechanism remains unclear. In this study, we showed that miR-106a expression is dramatically increased in lung cancer patients with bone metastasis (BM) by immunohistochemical analysis. MiR-106a promoted A549 and SPC-A1 cell proliferation, migration and invasion in vitro. The results of bioluminescence imaging (BLI), micro-CT and X-ray demonstrated that miR-106a promoted bone metastasis of lung adenocarcinoma in vivo. Mechanistic investigations revealed that miR-106a upregulation promoted metastasis by targeting tumour protein 53-induced nuclear protein 1 (TP53INP1)-mediated metastatic progression, including cell migration, autophagy-dependent death and epithelial–mesenchymal transition (EMT). Notably, autophagy partially attenuated the effects of miR-106a on promoting bone metastasis in lung adenocarcinoma. These findings demonstrated that restoring the expression of TP53INP1 by silencing miR-106a may be a novel therapeutic strategy for bone metastatic in lung adenocarcinoma.

We report the superconductivity of a new quaternary compound ThMo$_2$Si$_2$C, synthesized with the arc-melting technique. The compound crystallizes in a tetragonal CeCr$_2$Si$_2$C-type structure with cell parameters of $a$ = 4.2296 \r{A}and $c$ = 5.3571 \r{A}. An interlayer Si-Si covalent bonding is suggested by the atomic distance. The electrical resistivity and magnetic susceptibility measurements indicate a Pauli-paramagnetic metal with dominant electron-electron scattering in the normal-state. Bulk superconductivity at 2.2 K is demonstrated with a dimensionless specific-heat jump of ${\Delta}C/\gamma_{\rm n}T$ = 0.98. The superconducting parameters of the critical magnetic fields, coherence length, penetration depth, and superconducting energy gap are given., Comment: 14 pages, 6 figures, 3 tables. Accepted for publication in SCIENCE CHINA Physics, Mechanics & Astronomy

We collected in situ high-temperature powder X-ray diffraction (XRD) patterns, as well as Raman and Fourier transform infrared (FTIR) spectra on a natural serandite sample. The volumetric thermal expansion coefficient αV (K−1) is determined as a linear function of T (K): 37.6(5) × 10−9 × T + 11.1(3) × 10−6, with an averaged value of 31.7(10) × 10−6 K−1, while the anisotropy of axial thermal expansivities shows the order of αa > αb > αc. The isobaric Gruneisen parameters γiP are constrained as: 0.2–1.6 for most of the lattice vibrations below 500 cm−1; while 0–0.6 for the O–Si–O bending and Si–O stretching modes inside the Si3O9 chains above 500 cm−1. As compared with common silicate phases in the upper mantle and the transition zone, the γiP parameters for the internal vibrations are significantly smaller in silicate chains (serandite, enstatite) than those in Si2O7 groups (wadsleyite) and isolated SiO4 units (forsterite, pyrope), since the rotation of the bridging O atoms (in the direction perpendicular to Si–O–Si) could relax the SiO4 tetrahedra at elevated temperature. The OH-bending vibration of serandite is observed in both Raman-active (1378 cm−1) and IR-active (1389 cm−1) modes, with a temperature-dependence of − 0.07 and − 0.09 cm−1/K, respectively. The red-shift of these OH-bending modes with increasing temperature indicates that the hydrogen bond gets weaker as the O3…O4 distance becomes larger during thermal expansion. Additionally, our polarized FTIR spectra confirm that the stretching mode of the very strong hydrogen bond, a broad absorption region (1400–3300 cm−1), is polarized in the direction of E//b, as reported by Hammer et al. (Am Mineral 83:569–576, 1998).

The effect of powder characteristics on the thermal conductivity and mechanical properties of silicon nitride (Si 3 N 4 ) ceramics were investigated systematically by using two α-Si 3 N 4 powders a ...

The serviceability and safety level of bridges often deteriorates due to the environmental or operational conditions. A stochastic deterioration model is of essential importance for describing the time-variation of bridge performance (e.g., stiffness and strength), and for use in the estimate of bridge reliability under a probabilistic framework. In this context, the Gamma process has been widely used to model the resistance deterioration of aging bridges, yet suffers from the deficiency that the statistical characteristics of the process (namely mean value, variance and autocorrelation) are not mutually independent. This paper presents a new stochastic model for bridge resistance deterioration. As a modified version of the Gamma process-based one, the proposed model includes a new parameter that can release the dependence of the process autocorrelation and variance on the mean value. The impact of the new deterioration model on the time-dependent reliability of aging bridges is studied.

Many existing bridges suffer from resistance deterioration due to environmental or operational attacks and thus may rate under the anticipated performance requirements. The proof load testing is a commonly used approach to evaluate whether the bridge would have the capacity of carrying a certain load. The magnitude of proof load will determine the safety level of the proven bridge. A proof load test, if not designed properly, may potentially cause structural damage and even collapse to the bridge. This implies that the load testing should be oriented by a probability-based framework in an attempt to control the failure probability of the bridge. However, the current engineering practice insufficiently considers the risk control of proof load testings. This paper presents a reliability-based framework to guide and optimize the proof load testing for existing bridges. A mathematical model is developed to compute the target proof load, where two types of constraints are considered simultaneously: the acceptable structural safety level and the economic costs. A numerical example is presented to demonstrate the applicability of the proposed method. The framework developed in this paper can be used in practical engineering as an auxiliary decision-making tool for bridge load testings.

Understanding the spatial structure of wind speed profile of a tropical cyclone (TC) is of critical importance to assess the TC-related damage and map the risk for afflicted areas. The wind field structure of a TC can be regarded as a horizontal primary circulation superimposed by a vertical–radial secondary convection driven by thermal balance. The gradient wind field model has been widely utilized in literature to describe the radial distribution of wind speed with respect to the TC center. In this paper, a new gradient wind field model is developed for translating TCs, based on the vector summation of the rotational wind speed and the translation speed. The accuracy and efficiency of the proposed model are demonstrated through comparing the wind fields generated from model solution and those recorded historically. The proposed model only involves simple algebra, which is beneficial for practical applications, especially in simulation-based studies of TC wind field modeling.

Natural hazards such as hurricanes may cause extensive economic losses and social disruption for civil structures and infrastructures in coastal areas, implying the importance of understanding the construction performance subjected to hurricanes and assessing the hurricane damages properly. The intensity and frequency of hurricanes have been reported to change with time due to the potential impact of climate change. In this paper, a probability-based model of hurricane damage assessment for coastal constructions is proposed taking into account the non-stationarity in hurricane intensity and frequency. The non-homogeneous Poisson process is employed to model the non-stationarity in hurricane occurrence while the non-stationarity in hurricane intensity is reflected by the time-variant statistical parameters (e.g., mean value and/or standard deviation), with which the mean value and variation of the cumulative hurricane damage are evaluated explicitly. The Miami-Dade County, Florida, USA, is chosen to illustrate the hurricane damage assessment method proposed in this paper. The role of non-stationarity in hurricane intensity and occurrence rate due to climate change in hurricane damage is investigated using some representative changing patterns of hurricane parameters.

Probability-based assessment of hurricane damage costs for coastal communities is vital for policy-makers and insurers. The uncertainties associated with hurricane damage costs include both the inherent uncertainty due to the random nature of hurricane process and the model uncertainty of the mathematical representation of hurricane damage (vulnerability model). The hurricane vulnerability model has traditionally been modeled as a deterministic function of hurricane wind speed in the literature, without considering the effect of vulnerability model uncertainty on hurricane damage assessment. This paper develops two methods to assess the hurricane damage costs in the presence of vulnerability model uncertainty. To account for the non-stationarity in hurricane actions due to the potential impact of climate change, the hurricane occurrence process is modeled as a non-stationary Poisson process and the hurricane intensity is assumed to vary in time with time-variant statistical parameters of hurricane wind speed. A case study of Miami-Dade County, Florida, is conducted to illustrate the proposed methods and to investigate the impact of vulnerability model uncertainty on hurricane damage costs.

Continental orogens on Earth can be classified into accretionary orogen and collisional orogen. Magmatism in orogens occurs in every periods of an orogenic cycle, from oceanic subduction, continental collision to orogenic collapse. Continental collision requires the existence of prior oceanic subduction zone. It is generally assumed that the prerequisite of continental deep subduction is oceanic subduction and its drag force to the connecting passive-margin continental lithosphere during continental collision. Continental subduction and collision lead to the thickening and uplift of crust, but the formation time of the related magmatism in orogens depends on the heating mechanism of lithosphere. The accretionary orogens, on the other hand, have no strong continental collision, deep subduction, no large scale of crustal thrusting, thickening and uplift, and no UHP eclogite-facies metamorphic rocks related to continental deep subduction. Even though arc crust could be significantly thickened during oceanic subduction, it is still doubtful that syn- or post-collisional magmatism would be generated. In collisional orogens, due to continental deep subduction and significant crustal thickening, the UHP metamorphosed oceanic and continental crusts will experience decompression melting during exhumation, generating syn-collisional magmatism. During the orogen unrooting and collapse, post-collisional magmatism develops in response to lithosphere extension and upwelling of asthenospheric mantle, marking the end of an orogenic cycle. Therefore, magmatism in orogens can occur during the continental deep subduction, exhumation and uplift after detachment of subducted oceanic crust from continental crust, and extensional collapse. The time span from continental collision to collapse and erosion of orogens (the end of orogenic cycle) is 50-85 Myr. Collisional orogens are the key sites for understanding continental deep subduction, exhumation, uplift and orogenic collapse. Magmatism in collisional orogens plays important roles in continental reworking and net growth.

Power line carrier (PLC) technology plays an increasingly important role in the realization of cost-effective communication in a smart distribution grid. No current channel modeling method is universally applicable to more complex topologies that may emerge in smart grids, such as ring and mesh topologies. This paper presents a novel PLC channel modeling method based on the information node concept, and the universality and feasibility of the proposed method are demonstrated with applications in modeling networks with ring and mesh topologies. The factors that affect the channel characteristics of the networks and the laws that govern their behaviors for different types of topologies are analyzed. The validity and effectiveness of the proposed method are proven using simulation and laboratory tests. This paper provides the necessary theoretical basis and technical means to design the PLC modulation method for smart distribution grids.

Nosiheptide is one of the EU-approved sulfur-containing peptides in feed industry to inhibit the growth of the majority of Gram-positive bacteria. The main purpose of this study is directed to breed the high nosiheptide-producers by genome shuffling and ribosome engineering in Streptomyces actuosus AW7. The starting population for shuffling was generated by combining (60)Coγ-irradiation with LiCl mutagenesis treatments on the spores. After four rounds of protoplast fusion exposed to streptomycin as adaptive pressure, a high-yield recombinant strain D92 was obtained. In a 10-L fermenter, nosiheptide production reached 1.54 g/L which was 9.20-fold compared to that of the parental strain. Hyphae development, metabolic process, and ribosomal protein S12 sequence were investigated to characterize the differentiation among the recombinants. Several mutations in S12 were believed to be responsible to streptomycin resistance in the tested strain. The results demonstrated that the combination of genome shuffling and ribosome engineering is an efficient approach to breed high-yield industrial strains.

We report the antimony (Sb) doping effect in a prototype system of iron-based supercon-ductors LaFeAsO1-yFy (y=0, 0.1, 0.15). X-ray powder diffraction indicates that the lattice pa-rameters increase with Sb content within the doping limit. Rietveld structural refinements show that, with the partial substitution of Sb for As, while the thickness of the Fe2As2 layers increases significantly, that of the La2O2 layers shrinks simultaneously. So a negative chemical pressure is indeed "applied" to the superconducting-active Fe2As2 layers, in con-trast to the effect of positive chemical pressure by the phosphorus doping. Electrical resis-tance and magnetic susceptibility measurements indicate that, while the Sb doping hardly influences the SDW anomaly in LaFeAsO, it recovers SDW order for the optimally-doped sample of y=0.1. In the meantime, the superconducting transition temperature can be raised up to 30 K in LaFeAs1-xSbxO1-yFy with x=0.1 and y=0.15. The Sb doping effects are discussed in term of both J1-J2 model and Fermi Surface (FS) nesting scenario., Comment: 7 pages, 4 figures, 1 table. to be published in Science in China Series G