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Cyanocobalamin (CNCbl, the compound name of Vitamin B12) is the only mineral vitamin that is essential for growth and development and cannot be produced by animals. Some studies have found that CNCbl can promote the proliferation and migration of C2C12 cells, but the mechanism by which it affects muscle development is still unknown. In this study, we elucidated the effect of CNCbl on muscle development and studied its underlying mechanism. CNCbl could promote the differentiation of C2C12 cells and upregulate Acvr1, p-Smad2 and p-Smad3 in the TGF-β signaling pathway

Skyrmions and skyrmioniums are both topological non-trivial spin textures in chiral magnetic systems. The dynamics of these particle-like excitations can be distinguished according to their spin structures, and the controlled conversion between them is the key to the diversified functionalities of spintronic devices. In this study, the dynamics and evolution of chiral spin textures are investigated in [Pt/Co]3/Ru/[Co/Pt]3 multilayers with ferromagnetic interlayer exchange coupling. Reversible conversions between skyrmions and skyrmioniums can be realized by precisely controlling the domain wall through an applied magnetic field or electric current. Mediated by a multi-Q (winding number or topological number) cluster, skyrmions can be converted to skyrmioniums through two basic mechanisms. One way is to expand skyrmions by using sinusoidal pulses to form net domains, then to delete the stripe domains of the net domain to create the skyrmionium (reduce Q to zero). The second way is to drive multi-Q clusters to move and collapse into skyrmioniums with square pulses. The skyrmion Hall effect of skyrmioniums has been suppressed to zero, which supports that the winding number of skyrmioniums indeed is reduced to zero. We have also directly observed the topological conversion of a skyrmionium into skyrmion, characterized by the abrupt emergence of the skyrmion Hall effect. The establishment of reversible conversions between different magnetic topological spin textures is an important development, which should speed the advent of the next generation of spintronic device.

The UBX domain containing protein 1-like gene (UBXN1) promotes the degradation of myofibrillar proteins during meat maturation, which affects meat water-holding capacity (WHC). This study aims to identify functional mutations in UBXN1 promoter region, which affects the transcription activity and therefore the WHC. Firstly, we confirmed that the UBXN1 expression level was positively associated with WHC. Individuals with high and low WHC (n=16 per group) were selected from 168 Duroc × Large White × Yorkshire (D × L × Y) crossbred pigs. The UBXN1 promoter region was comparatively sequenced using DNA pools from these two groups, and a mutation ca. −379T > G was revealed that had reverse allele distribution. The single nucleotide polymorphism (SNP) was then genotyped in the abovementioned population. TT genotype individuals exhibited higher UBXN1 mRNA level and higher WHC compared with GG genotype ones. Further luciferase assay confirmed that TT genotype promoter had higher activity. Moreover, the degradation of cytoskeletal framework proteins of muscle cells like desmin, synemin, dystrophin, and vinculin was higher in TT genotype individuals than GG ones. In conclusion, we identified a SNP in the UBXN1 gene promoter that contributes to WHC improvement and pork quality. And UBXN1 is a strong candidate gene in regulation of pork WHC.

Small nucleolar RNA SNORD50A and SNORD50B (SNORD50A/B) has been reported to be recurrently deleted and function as a putative tumor suppressor in different types of cancer by binding to and suppressing the activity of the KRAS oncoproteins. Its deletion correlates with poorer patient survival. However, in this study, we surprisingly found that SNORD50A/B loss predicted a better survival in breast cancer patients carrying wild-type p53. Functional studies showed that SNORD50A/B deletion strongly inhibited the proliferation, migration, invasion and tumorigenic potential, and induced cell cycle arrest and apoptosis in p53 wild-type breast cancer cells, while exerted the opposite effects in p53 mutated breast cancer cells. This was also supported by ectopically expressing SNORD50A/B in both p53 wild-type and mutated breast cancer cells. Mechanistically, SNORD50A/B clearly enhances the interaction between E3 ubiquitin ligase TRIM21 and its substrate GMPS by forming a complex among them, thereby promoting GMPS ubiquitination and its subsequent cytoplasmic sequestration. SNORD50A/B deletion in p53 wild-type breast cancer cells will release GMPS and induce the translocation of GMPS into the nucleus, where GMPS can recruit USP7 and form a complex with p53, thereby decreasing p53 ubiquitination, stabilizing p53 proteins, and inhibiting malignant phenotypes of cancer cells. Altogether, the present study first reports that SNORD50A/B plays an oncogenic role in p53 wild-type breast cancers by mediating TRIM21-GMPS interaction.

Obesity, which is associated with type 2 diabetes, is a threat to human health. There are studies, which suggest that some compounds can induce browning of white adipocytes to combat obesity. In this study, we selected nonivamide, an analog of capsaicin, to detect whether it influenced the browning of porcine white adipocytes. First, we found 25 μM nonivamide promoted apoptosis of porcine subcutaneous pre-adipocytes. After pre-adipocytes differentiation, nonivamide inhibited adipogenesis by reducing the expressions of Pparγ, Cebpα, while it promoted lipolysis by up-regulating Hsl, Atgl. Nonivamide also induced browning of porcine subcutaneous adipocytes by up-regulating the expression of brown and beige adipocyte gene markers, such as Prdm16, Cidea, and Slc27a1. Additionally, thermogenesis gene markers Cpt1a and Cpt1b were significantly up-regulated by nonivamide. Furthermore, nonivamide promoted mitochondrial biogenesis by up-regulating the expression of Tfam, Nrf1, Nrf2, and Tomm20. In conclusion, nonivamide is a potent compound to induce porcine adipocyte browning for treating obesity.

Intramuscular fat (IMF) is considered as the fat deposited between muscle fibers. The extracellular matrix microenvironment of adipose tissue is of critical importance for the differentiation, remodeling and function of adipocytes. Therefore, in this study we extracted the muscle tissue centrifugal fluid (MTF) of the longissimus dorsi of Erhualian pigs to mimic the microenvironment of intramuscular pre-adipocytes. MTF of pigs with low intramuscular fat level can inhibit pig intramuscular pre-adipocytes differentiation. Then, proteomics technology (iTRAQ) was used to analyze the MTF with different IMF content, and it was found that individuals with high IMF had low ACAT2 (Acyl-CoA: cholesterol acyltransferases 2) levels, while individuals with low IMF had high ACAT2 levels. Significant changes took place in the pathways involved in coenzyme A, which are closely related to fat and cholesterol metabolism. Therefore, we speculate that ACAT2, as an important element involved in cholesterol metabolism, may become a potential molecular marker for the mechanism of pig intramuscular preadipocytes differentiation. Overexpression of ACAT2 in pig intramuscular pre-adipocytes can inhibit their differentiation, while adding ACAT2 inhibitor avasimibe can rescue the process. Knockdown of srebp2 or ldlr, which are two key genes closely related to ACAT2 and cholesterol metabolism, can inhibit pig intramuscular pre-adipocytes differentiation. Overall, our results suggest that ACAT2 is a novel negative regulator of intramuscular adipocyte differentiation through regulation of pparγ, cebpα signaling and srebp2/ldlr signaling involved in cholesterol metabolism.

Write asymmetry, the significantly different write current for high-to-low and low-to-high resistance switching because of natural stochastic behaviors of magnetization, is a fundamental issue in magnetic random-access memory (MRAM). For high-performance spin transfer torque (STT) MRAM, it can be eliminated by precisely controlling atomically thin magnetic multilayers or by introducing compensation techniques in circuit-level designs, while for spin-orbit torque (SOT) MRAM, it has not been addressed. Here we systematically investigated the write asymmetry of SOT-MRAM as a function of applied magnetic fields (H) and demonstrated that the write currents are intrinsically asymmetric due to different SOT efficiencies for high-to-low and low-to-high switching. Furthermore, we found that the SOT efficiency is very sensitive to the tilt angle between H and write current, which can be tuned through H to achieve symmetric SOT switching. These results provide an additional guideline for designing SOT devices and suggest that the write asymmetry can be eliminated by adjusting the introduced effective magnetic fields within a field-free SOT-MRAM architecture., 4 pages, 4 figures

The activating TERT promoter mutations and BRAFV600E mutation are well-established oncogenic alterations in human cancers. Coexistence of BRAFV600E and TERT promoter mutations is frequently found in multiple cancer types, and is strongly associated with poor patient prognosis. Although the BRAFV600E-elicited activation of ERK has been demonstrated to contribute to TERT reactivation by maintaining an active chromatin state, it still remains to be addressed how activated ERK is selectively recruited to mutant TERT promoter. Here, we report that transcription factor GABPA mediates the regulation of BRAFV600E/MAPK signaling on TERT reactivation by selectively recruiting activated ERK to mutant TERT promoter, where activated ERK can phosphorylate Sp1, thereby resulting in HDAC1 dissociation and an active chromatin state. Meanwhile, phosphorylated Sp1 further enhances the binding of GABPA to mutant TERT promoter. Taken together, our data indicate that GABPA and Sp1 synergistically activate mutant TERT promoter, contributing to tumorigenesis and cancer progression, particularly in the BRAFV600E-driven human cancers. Thus, our findings identify a direct mechanism that bridges two frequent oncogenic alterations together in TERT reactivation.

MicroRNAs (miRNAs), as a series of important short-chain non-coding RNAs, play an important post-transcriptional role in many biological activities, including adipogenesis. miR-144 is significantly upregulated in type II diabetes (T2D), and is considered to be an important biomarker for T2D. However, although the occurrence of T2D is inextricably linked to adipogenesis, whether miR-144 directly regulates adipogenesis remains to be further explored. In this paper, we demonstrate that miR-144 has a higher expression level in a porcine high backfat group, and it has a significant positive effect on promoting the differentiation of pre-adipocytes. FoxO1 is a target gene of miR-144, and inhibits the differentiation of pre-adipocytes. On the other hand, we demonstrate that FoxO1 can bind to the AdipoQ gene promoter, then regulate the AdipoQ expression by binding to the FoxO1 binding site in the AdipoQ promoter -1,499 to -1,489 bp and -1,238 to -1,228 bp regions, especially the -1,499 to -1,489 bp region. Meanwhile, miR-144 and FoxO1 co-expressional research has also shown that both factors regulate adipogenesis. To sum up, our research indicates that miR-144 targets FoxO1, thus reducing its expression and inhibiting its promotional effect on adiponectin, thereby alleviating the inhibitory effect of adiponectin on adipogenesis.

Surface roughness plays an important role on the magnetotransport properties of thin films, especially in ultrathin films. In this work, we prepared Fe thin films with various surface roughness by using different seed layers and studied the electrical transport and anomalous Hall effect. By tuning surface roughness scattering, the longitudinal resistivity (${\ensuremath{\rho}}_{xx}$) measured at 5 K increases by one order of magnitude and the corresponding anomalous Hall resistivity (${\ensuremath{\rho}}_{\mathrm{AHE}}$) increases by three times with increasing roughness. The intrinsic, skew-scattering, and side-jump contributions to ${\ensuremath{\rho}}_{\mathrm{AHE}}$ were separated from our data. The anomalous Hall angle depends on the surface roughness, which may be of importance to the material engineering for achieving large spin Hall angle.

Perpendicular magnetization switching driven by spin–orbit torques plays an increasingly important role for spintronic devices toward practical applications but is also hindered by the well-known technical challenge that an external in-plane magnetic field is required for deterministic switching. Here, we show that the deterministic switching can be achieved in synthetic antiferromagnets through the flexible domain control in the absence of external magnetic fields. Specifically, we have observed that the domain wall (DW) distorts under an applied electric current in contrast to the conventional rigid DW motion in a single ferromagnet. More importantly, the distorted DWs can be precisely controlled under zero magnetic field, leading to the deterministic switching. Our results indicate that the critical technical challenge may be addressed by employing a synthetic antiferromagnetic layer through the DW motion dominated field-free switching.

Strain-mediated ferromagnetic/ferroelectric (FE) heterostructures have played an important role in multiferroic materials to investigate the electric-field control of magnetism in the past decade, due to their excellent performances, such as room-temperature operation and large magnetoelectric (ME) coupling effect. Because of the different FE-switching-originated strain behaviors and varied interfacial coupling effect, both loop-like (nonvolatile) and butterfly-like (volatile) converse ME effects have been reported. Here, we investigate the electric-field control of magnetism in a multiferroic heterostructure composed of a polycrystalline Fe thin film and a Pb(Mg1/3Nb2/3)0.7Ti0.3O3 single crystal, and the experimental results exhibit complex behaviors, suggesting the coexistence of volatile and nonvolatile converse ME effects. By separating the symmetrical and antisymmetrical parts of the electrical modulation of magnetization, we distinguished the loop-like hysteresis and butterfly-like magnetization cha...

Antiferromagnetic (AFM) skyrmionium composed of two topological AFM skyrmions shares the merits of an AFM skyrmion, for example, high mobility and no skyrmion Hall effect. Here, we analytically and numerically study the dynamics of the AFM skyrmion and skyrmionium induced by spin currents. Our calculations demonstrate that the current-induced spin-transfer torques can drive AFM skyrmion and skyrmionium with the same speed, while their steady motion speeds induced by spin-orbit torques are different. Furthermore, it is found that due to the existence of the effective AFM texture mass, the AFM skyrmion and skyrmionium obey the momentum theorem, and the time evolution of the position induced by alternating currents presents a phase. Besides, a spin torque nano-oscillator based on the AFM skyrmionium can produce high frequencies, similar to that based on the AFM skyrmion. Numerical simulations are in good agreement with the analytical solutions. Our results demonstrate the inertial dynamics of the AFM skyrmion and skyrmionium and may provide guidelines for building skyrmion-based spintronic devices.

We report reversible and nonvolatile fully electrical control of magnetic tunnel junctions deposited on a ferroelectric substrate., One of the motivations for multiferroics research is to find an energy-efficient solution to spintronic applications, such as the solely electrical control of magnetic tunnel junctions. Here, we integrate spintronics and multiferroics by depositing MgO-based magnetic tunnel junctions on ferroelectric substrate. We fabricate two pairs of electrodes on the ferroelectric substrate to generate localized strain by applying voltage. This voltage-generated localized strain has the ability to modify the magnetic anisotropy of the free layer effectively. By sequentially applying voltages to these two pairs of electrodes, we successively and unidirectionally rotate the magnetization of the free layer in the magnetic tunnel junctions to complete reversible 180° magnetization switching. Thus, we accomplish a giant nonvolatile solely electrical switchable high/low resistance in magnetic tunnel junctions at room temperature without the aid of a magnetic field. Our results are important for exploring voltage control of magnetism and low-power spintronic devices.

The work reported in this publication was supported by King Abdullah University of Science and Technology (KAUST) through the Office of Sponsored Research (OSR) (Grant No. OSR-2015-CRG4-2626).

We study the magnetic domain pattern in a ferrimagnetic CoTb thin film using Lorentz transmission electron microscopy. The evolution of domain patterns is captured at different temperatures and external fields. Magnetic dipole skyrmions and bubbles can be created simultaneously by increasing the temperature of the sample and applying appropriate out-of-plane magnetic fields. By tuning the external magnetic fields, it is found that the skyrmions are annihilated at a higher magnetic field compared to bubbles. Moreover, we also find that the in-plane magnetic field influences the formation and the shape of skyrmions and bubbles. Further, micromagnetic simulations are also consistent with the experimental observations. Our findings provide insights into the magnetic field stability of skyrmions.

Magnetic skyrmions are particle-like topological spin configurations, which can carry binary information and thus are promising building blocks for future spintronic devices. In this work, we investigate the relationship between the skyrmion dynamics and the characteristics of injected current in a skyrmion-based spin torque nano-oscillator, where the excitation source is introduced from a point nano-contact at the center of the nanodisk. It is found that the skyrmion will move away from the center of the nanodisk if it is driven by a spin-polarized current; however, it will return to the initial position in the absence of stimulus. Therefore, we propose a skyrmion-based artificial spiking neuron, which can effectively implement the leaky-integrate-fire operation. We study the feasibility of the skyrmion-based spiking neuron by using micromagnetic simulations. Our results may provide useful guidelines for building future magnetic neural networks with ultra-high density and ultra-low energy consumption., 5 pages, 5 figures

Cooper pairs in superconductors are normally spin singlet. Nevertheless, recent studies suggest that spin-triplet Cooper pairs can be created at carefully engineered superconductor-ferromagnet interfaces. If Cooper pairs are spin-polarized they would transport not only charge but also a net spin component, but without dissipation, and therefore minimize the heating effects associated with spintronic devices. Although it is now established that triplet supercurrents exist, their most interesting property - spin - is only inferred indirectly from transport measurements. In conventional spintronics, it is well known that spin currents generate spin-transfer torques that alter magnetization dynamics and switch magnetic moments. The observation of similar effects due to spin-triplet supercurrents would not only confirm the net spin of triplet pairs but also pave the way for applications of superconducting spintronics. Here, we present a possible evidence for spin-transfer torques induced by triplet supercurrents in superconductor/ferromagnet/superconductor (S/F/S) Josephson junctions. Below the superconducting transition temperature T_c, the ferromagnetic resonance (FMR) field at X-band (~ 9.0 GHz) shifts rapidly to a lower field with decreasing temperature due to the spin-transfer torques induced by triplet supercurrents. In contrast, this phenomenon is absent in ferromagnet/superconductor (F/S) bilayers and superconductor/insulator/ferromagnet/superconductor (S/I/F/S) multilayers where no supercurrents pass through the ferromagnetic layer. These experimental observations are discussed with theoretical predictions for ferromagnetic Josephson junctions with precessing magnetization., 7 pages, 8 figures

We investigated the mechanism(s) of the anomalous Hall effect (AHE) in magnetic granular materials by fabricating 100 nm-thick thin films of Co

Strain-mediated ferromagnetic/ferroelectric (FE) heterostructures have played an important role in multiferroic materials to investigate the electric-field control of magnetism in the past decade, due to their excellent performances, such as room-temperature operation and large magnetoelectric (ME) coupling effect. Because of the different FE-switching-originated strain behaviors and varied interfacial coupling effect, both loop-like (nonvolatile) and butterfly-like (volatile) converse ME effects have been reported. Here, we investigate the electric-field control of magnetism in a multiferroic heterostructure composed of a polycrystalline Fe thin film and a Pb(Mg

We investigated current driven spin-orbit torques in $\mathrm{C}{\mathrm{u}}_{40}\mathrm{A}{\mathrm{u}}_{60}/\mathrm{N}{\mathrm{i}}_{80}\mathrm{F}{\mathrm{e}}_{20}/\mathrm{Ti}$ layered structures with in-plane magnetization. We have demonstrated a reliable and convenient method to separate dampinglike torque and fieldlike torque by using the second harmonic technique. It is found that the dampinglike torque and fieldlike torque depend on temperature very differently. Dampinglike torque increases with temperature, while fieldlike torque decreases with temperature, which are different from results obtained previously in other material systems. We observed a nearly linear dependence between the spin Hall angle and longitudinal resistivity, suggesting that skew scattering may be the dominant mechanism of spin-orbit torques.

Composited Bi4Ti3O12@ZnO nanoparticles with a core of Bi4Ti3O12 (BIT) and a shell of ZnO have been synthesized by liquid chemical reaction method. Compared with pure BIT nanoparticles, the ferroelectricity in BIT@ZnO core–shell nanostructure was greatly enhanced. Moreover, the dielectric loss of BIT@ZnO is lower than that of BIT nanoparticles in a low frequency range. The band gap energy of BIT@ZnO core@shell nanostructure is larger than that of BIT, which formed as a type-II band alignment. Furthermore, the BIT@ZnO core–shell nanoparticles exhibit better UV photodegradation activity for organic contaminant. Such a BIT@ZnO core@shell nanostructure may have potential applications in microelectronics, photoelectronic, and photocatalytic of contamination.

Highly pure butterfly-shaped BiFeO3@BaTiO3 nanotubes have been synthesized through a sol–gel method. An obvious ferromagnetic behavior was obtained at room temperature, with a large coercive field (5,403 Oe) and high Mr/Ms value (0.52). The dielectric permittivity of BiFeO3@BaTiO3 nanotubes was found to be 1919, which is much higher than that of pure BFO nanostructure. The dielectric loss of BiFeO3@BaTiO3 nanotubes is low in the frequency range from 10 Hz to 1 MHz. The maximum magnetoelectric coefficient of BiFeO3@BaTiO3 nanotube is 0.272 μV/cm Oe. Moreover, the BiFeO3@BaTiO3 nanotubes have exhibited a better ferroelectric property with a large band gap of 3.2 eV which demonstrates the core–shell nanostructure.

The exchange bias phenomenon has been investigated in multiferroic Eu0.75Y0.25MnO3. The material shows a weak ferromagnetism with cone spin configuration induced by external magnetic field below 30 K. Consequently, the electric polarization coming from the cycloid spin order below 30 K can be suppressed by external magnetic fields. The magnetic hysteresis loops after cooling in a magnetic field exhibit characteristics of exchange bias below the spin glassy freezing temperature (T-g)similar to 16 K. The exchange bias field, coercivity field, and remanent magnetization increase with increasing cooling magnetic field. The exchange bias effect is ascribed to the frozen uncompensated spins at the antiferromagnetism/weak ferromagnetism interfaces in the spin-glass like phase. (C) 2012 Elsevier B.V. All rights reserved.

This work was supported by the National Science Foundation of China (Grant Nos. 11434006, 11774199, and 51871112), the National Basic Research Program of China (Grant No. 2015CB921502), the 111 ProjectB13029, and the Taishan Scholar Program of Shandong Province. H.Z. was supported by the King Abdullah University of Science and Technology (KAUST) during his visit to KAUST. X.X.Z. acknowledges the support from KAUST.

A series of isotactic polypropylene (iPP)/calcium carbonate (CaCO3) composites are prepared by melt blending, and the crystallisation behaviours of these composites are investigated by differential scanning calorimetry (DSC). The results show that the crystallisation exotherms displayed double peaks as the concentration of CaCO3 reaches a critical value of typically ∼8 wt-% for nano-CaCO3 and ∼20 wt-% for micron-CaCO3. With increasing content of CaCO3, the intensity of the higher temperature crystallisation peak increases, while that of the lower one decreases. Modifying the surface of CaCO3 with stearic acid leads to the increase in the critical concentration to trigger double crystallisation peaks, which is 50 wt-% for nano-CaCO3 filled iPP. The results of isothermal crystallisation, transmission electron microscopy (TEM) and polarised light optical microscope (POM) experiments indicate that the different nucleating abilities of CaCO3 composites are mainly responsible for the occurrence of the d...

Magnetic skyrmions are topologically protected nanoscale spin textures exhibiting fascinating physical behaviors. Recent observations of room temperature skyrmions in sputtered multilayer films are an important step towards their use in ultra-low power devices. Such practical applications prefer skyrmions to be stable at zero magnetic fields and room temperature. Here, we report the creation of skyrmion lattices in Pt/Co/Ta multilayers by a scanning local field using magnetic force microscopy tips. We also show that those newly created skyrmion lattices are stable at both room temperature and zero fields. Lorentz transmission electron microscopy measurements reveal that the skyrmions in our films are of Neel-type. To gain a deeper understanding of the mechanism behind the creation of a skyrmion lattice by the scanning of local fields, we perform micromagnetic simulations and find the experimental results to be in agreement with our simulation data. This study opens another avenue for the creation of skyrmion lattices in thin films.

Novel poly(ether ether ketone) (PEEK)/organically modified montmorillonite (OMMT) composites containing 0–10 wt-% fractions of OMMT were prepared by melting blending method and the microstructure, thermal and mechanical properties were investigated using different characterisation techniques. X-ray diffraction and transmission electron microscopy showed that the OMMT was well dispersed with microscale in the PEEK matrix. Differential scanning calorimetry indicated that the glass transition temperature T g and melt temperature T m of PEEK/OMMT composites (POMCs) were hardly affected by the addition of OMMT, while the crystal temperature T c decreased when the amount of OMMT excessed 1 wt-%. The data of thermogravimetric analysis exhibited that the thermal stability of POMCs in higher temperature region was better than that of pure PEEK. The results of mechanical properties test revealed that modulus and strength of POMCs increased with the content of OMMT, whereas the elongation at break and impact...

In this paper, we report the fabrication of the FeCrMoCBErMe (Me=Al, Be, In, Nb, Ni and Pb) amorphous steels with high Fe content (>58 at.%). These structural amorphous steels (SASs) show very good glass-forming ability and can be readily cast into bulk glass with a diameter of at least 8 mm using industrial-grade elements. The glassy formation and properties, in particular the elastic property as well as its correlation with the constituent elements of the alloy are studied. The results may assist in the understanding of the formation mechanism of the metallic glasses and provide useful guideline for the development of property-controllable SASs. These new amorphous steels have a low manufacturing cost due to their high iron content, and thus they are more viable for applications.