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Background: Platelet transfusion therapy has made a great breakthrough in clinical practice, and the differentiation of human embryonic stem cells (hESCs) to produce functional platelets has become a new potential approach, however, efficient generation of functional platelets still faces great challenges. Here, we presented a novel approach to highly and efficiently generate mature megakaryocytes (MKs) and functional platelets from hESCs. Methods: In hypoxic conditions, we successfully replicated the maturation process of MKs and platelets in a controlled in vitro environment by introducing an optimal combination of cytokines at various stages of development. This method led to the generation of MKs and platelets derived from hESCs. Subsequently, mature MKs and functional platelets were further comprehensively investigated and characterized using a variety of methodologies, including flow cytometry analysis, RT-qPCR validation, Giemsa-Wright's staining, immunofluorescent staining, RNA transcriptome analysis, and DNA ploidy analysis. Additionally, the in vivo function of platelets was evaluated through the transplantation using thrombocytopenia model mice. Results: Under our 3D differentiation conditions with four sequential stages, hESCs could be efficiently induced into mature MKs, with 95% expressing CD41aCD42a or 90% expressing CD41aCD42b, and those MKs exhibited polyploid properties, produced filamentous proplatelet structures and further generated platelets. Furthermore, 95% of platelets showed CD42b+CD62p+ phenotype upon the stimulation with ADP and TRAP-6, while 50% of platelets exhibited the ability to bind PAC-1, indicating that hESC-derived platelets possessed the in vitro functionality. In mice models of thrombocytopenia, hESC-derived platelets effectively restored hemostasis in a manner comparable to human blood-derived platelets. Further investigation on the mechanism of this sequential differentiation revealed that cellular differentiation and molecular interactions during the generation of hESC-derived MKs and platelets recapitulated the developmental trajectory of the megakaryopoiesis and thrombopoiesis. Conclusions: Thus, our results demonstrated that we successfully established a highly efficient differentiation of hESCs into mature MKs and functional platelets in vitro. The in vivo functionality of hESC-derived platelets closely resembles that of natural human platelets, thus offering a promising avenue for the development of functional platelets suitable for future clinical applications. [ABSTRACT FROM AUTHOR]

We present a design of an ultrafast spin current emitter utilizing the Au nanoparticles/Co/Pt heterostructures, which facilitate significant enhancement in terahertz radiation. Using Au nanoparticles synthesized by thermal annealing and embedded in Co/Pt bilayers, we show that the Au nanoparticles fulfill surface plasmon resonance conditions under the illumination of femtosecond laser pulses, and enhanced terahertz spin currents are generated in the Co thin film. The terahertz signal amplitude of Au nanoparticles/Co/Pt sample exhibits an enhancement of 70% and 45% compared to that observed in Au thin film/Co/Pt and Co/Pt samples, respectively. By integrating experimental analysis and numerical calculations, we ascribe the enhancement of terahertz emission amplitude to the contribution of spin current generated by surface plasmon resonance in the Co thin film, which may result from the magnetization enhancement induced by surface plasmon-excited electromagnetic fields at the Au nanoparticles/Co interface, and the plasmon-induced spin current density is approximately 1 × 1029 electrons s−1 m−2. This plasmon-induced spin current establishes a connection between the fields of plasmonic and spintronic physics, thereby promoting the development of spintronic terahertz emitters. [ABSTRACT FROM AUTHOR]

A series of (Ni80Fe20)1-x(Ni0.5Zn0.5Fe2O4)x films were fabricated on Si substrates by means of radio frequency magnetron sputtering and the electrical and magnetic properties were studied. Optimal films with the desired properties of low coercivity Hc ∼ 4 Oe, high saturation magnetization 4πMs ∼ 14.5 kG, and high electrical resistivity ρ ∼ 1500 μΩ cm were obtained. The permeability spectra measured shows that its natural ferromagnetic resonant frequency was about 3.4 GHz. The tested results shown that the sputtering power had an important effect on the films properties and that it can be convenient to adjust the natural ferromagnetic resonant frequency of the films. [ABSTRACT FROM AUTHOR]

Crystal structure, microstructure, static and dynamic magnetic properties of Ba 3-x Nd x Co 2 Fe 24 O 41 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) ceramics were investigated. Samples were prepared via sintering at 1250 °C for 4 h, and XRD results revealed their crystal structure after Nd substitution. With the increase in Nd3+ ion dopant content, particle porosity increased, leading to slight decrease in volume density. Static magnetic data showed the weak effect of Nd-substitution on saturation magnetization strength and a slight increase in coercivity (from 52 Oe to 75 Oe at x = 0–0.5), while out-of-plane magnetic anisotropy rose significantly (from 10.1 kOe to 14.5 kOe at x = 0–0.5). Dynamic magnetic tests demonstrated noticeable decrease in permeability (from 17 to 8), whereas cutoff frequency increased from 0.8 GHz to 1.9 GHz and the maximum Snoek product reached 18.8 GHz for the sample with x = 0.4. The fitting of real part of permeability using domain wall resonance and natural resonance models revealed that resonance frequency and out-of-plane anisotropy both increased with Nd-substitution. Moreover, despite Nd doping, samples maintained low magnetic loss and high Q value within higher frequency range. Therefore, findings of this study provide a pathway to development of substituted Z-type barium (Co 2 Z) ferrites for high frequency applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Exosomes secreted from stem cells exerted salutary effects on the fibrotic liver. Herein, the roles of exosomes derived from human embryonic stem cell (hESC) in anti-fibrosis were extensively investigated. Compared with two-dimensional (2D) culture, the clinical and biological relevance of three-dimensional (3D) cell spheroids were greater because of their higher regeneration potential since they behave more like cells in vivo. In our study, exosomes derived from 3D human embryonic stem cells (hESC) spheroids and the monolayer (2D) hESCs were collected and compared the therapeutic potential for fibrotic liver in vitro and in vivo. Results: In vitro, PKH26 labeled-hESC-Exosomes were shown to be internalized and integrated into TGFβ-activated-LX2 cells, and reduced the expression of profibrogenic markers, thereby regulating cellular phenotypes. TPEF imaging indicated that PKH26-labeled-3D-hESC-Exsomes possessed an enhanced capacity to accumulate in the livers and exhibited more dramatic therapeutic potential in the injured livers of fibrosis mouse model. 3D-hESC-Exosomes decreased profibrogenic markers and liver injury markers, and improved the level of liver functioning proteins, eventually restoring liver function of fibrosis mice. miRNA array revealed a significant enrichment of miR-6766-3p in 3D-hESC-Exosomes, moreover, bioinformatics and dual luciferase reporter assay identified and confirmed the TGFβRII gene as the target of miR-6766-3p. Furthermore, the delivery of miR-6766-3p into activated-LX2 cells decreased cell proliferation, chemotaxis and profibrotic effects, and further investigation demonstrated that the expression of target gene TGFβRII and its downstream SMADs proteins, especially phosphorylated protein p-SMAD2/3 was also notably down-regulated by miR-6766-3p. These findings unveiled that miR-6766-3p in 3D-hESC-Exosomes inactivated SMADs signaling by inhibiting TGFβRII expression, consequently attenuating stellate cell activation and suppressing liver fibrosis. Conclusions: Our results showed that miR-6766-3p in the 3D-hESC-Exosomes inactivates smads signaling by restraining TGFβRII expression, attenuated LX2 cell activation and suppressed liver fibrosis, suggesting that 3D-hESC-Exosome enriched-miR-6766-3p is a novel anti-fibrotic therapeutics for treating chronic liver disease. These results also proposed a significant strategy that 3D-Exo could be used as natural nanoparticles to rescue liver injury via delivering antifibrotic miR-6766-3p. [ABSTRACT FROM AUTHOR]

We present a reconfigurable nanoscale spin-wave directional coupler based on spin-orbit torque (SOT). By micromagnetic simulations, it is demonstrated that the functionality and operating frequency of proposed device can be dynamically switched by inverting the whole or part of the relative magnetic configuration of the dipolar-coupled waveguides using SOT. Utilizing the effect of sudden change in coupling length, the functionality of power divider can be realized. The proposed reconfigurable spin-wave directional coupler opens a way for two-dimensional planar magnonic integrated circuits. [ABSTRACT FROM AUTHOR]

The support properties can be tuned through changing the addition amount of Zr. As a result, the formation and stability of Co species can be regulated, then, the relationships between different Co species and reaction pathways have been revealed. [Display omitted] TiO 2 , ZrO 2 and a series of TiO 2 -ZrO 2 (TxZ1, x means the atomic ratio of Ti/Zr = 10, 5, 1, 0.2 and 0.1) composite oxide supports were prepared through co-precipitation, and then 3 wt% Co was loaded through wetness impregnation methods. The obtained 3 wt% Co/TiO 2 (3CT), 3 wt% Co/ZrO 2 (3CZ) and 3 wt% Co/TxZ1 (3CTxZ1) catalysts were evaluated for the oxidative ethane dehydrogenation reaction with CO 2 (CO 2 -ODHE) as a soft oxidant. 3CT1Z1 catalyst exhibits excellent catalytic properties, with C 2 H 4 yield, C 2 H 6 conversion and CO 2 conversion about 24.5 %, 33.8 % and 18.0 % at 650 °C, respectively. X-Ray Diffraction (XRD), in-situ Raman, UV–vis diffuse reflectance spectra (UV–vis DRS), H 2 temperature-programmed reduction (H 2 -TPR), Electron paramagnetic resonance (EPR) and quasi in-situ X-ray Photoelectron Spectroscopy (XPS) have been utilized to thoroughly characterize the investigated catalysts. The results revealed that 3CT1Z1 produced TiZrO 4 solid solution with more metal defect sites and oxygen vacancies (Ov), promoting the formation of Co2+-TiZrO 4 structure. Furthermore, the presence of Ov and Ti3+can facilitate the high dispersion and stabilization of Co2+, as well as suppressing the severe reduction of Co2+, leading to superior ethane oxidative dehydrogenation activity. Besides, less Co0 is beneficial to ODHE reaction, because of its promotion effects for reverse water gas shift reaction; however, more Co0 results in dry reforming reaction (DRE). This work will shed new lights for the design and preparation of highly efficient catalysts for ethylene production. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 nanotubes (TNTs) have drawn tremendous attention owing to their unique architectural and physical properties. Anodizing of titanium foil has proven to be the most efficient method to fabricate well-aligned TNTs, which, however, usually produces amorphous TNTs and needs further thermal annealing. Recently, a water-assisted crystallization strategy has been proposed and investigated by both science and engineering communities. This method is very efficient and energy saving, and it circumvents the drawbacks of thermal sintering approach. In this paper, we review the recent research progress in this kind of low-temperature crystallization approach. Here, various synthetic methods are summarized, and the mechanisms of the amorphous-crystalline transformation are analyzed. The fundamental properties and applications of the low-temperature products are also discussed. Furthermore, it is proved that the water-assisted crystallization approach is not only applicable to TNTs but also to crystallizing other metal oxides. [ABSTRACT FROM AUTHOR]

Based on highly ordered TiO2 nanotube arrays (NTAs), we successfully fabricated the Cu2O-TiO2 NTA heterojunction by a simple thermal decomposition process for the first time. The anodic TiO2 NTAs were functioned as both “nano-container” and “nano-reactors” to load and synthesize the narrow band Cu2O nanoparticles. The loaded Cu2O expanded absorption spectrum of the TiO2 NTAs from ultraviolent range to visible light range. We found that the Cu2O-TiO2 NTA heterojunction films had visible activity towards photocatalytic degrading methyl orange (MO). The photocatalytic abilities of the Cu2O-TiO2 NTA heterojunction films were found increased with the Cu2O content from 0.05 to 0.3 mol/L. This could be explained by more electron-hole pairs generated and less recombination, when the Cu2O-TiO2 heterojunction got formed. Here, we put forward this promising method, hoping it can facilitate the mass production and applications of Cu2O-TiO2 NTA heterojunction. [ABSTRACT FROM AUTHOR]

In this paper, a facile method was proposed to load CeO2 nanoparticles (NPs) on anodic TiO2 nanotube (NT) arrays, which leads to a formation of CeO2/TiO2 heterojunctions. Highly ordered anatase phase TiO2 NT arrays were fabricated by using anodic oxidation method, then these individual TiO2 NTs were used as tiny “nano-containers” to load a small amount of Ce(NO3)3 solutions. The loaded anodic TiO2 NTs were baked and heated to a high temperature of 450 °C, under which the Ce(NO3)3 would be thermally decomposed inside those nano-containers. After the thermal decomposition of Ce(NO3)3, cubic crystal CeO2 NPs were obtained and successfully loaded into the anodic TiO2 NT arrays. The prepared CeO2/TiO2 heterojunction structures were characterized by a variety of analytical technologies, including XRD, SEM, and Raman spectra. This study provides a facile approach to prepare CeO2/TiO2 films, which could be very useful for environmental and energy-related areas. [ABSTRACT FROM AUTHOR]

Gilbert damping in magnetic systems describes the relaxation of magnetization. This term was phenomenologically introduced into the Landau–Lifschitz–Gilbert (LLG) equation to describe spin dynamics. In most studies, such as magnetic random access memory, spin-wave propagations, and microwave devices, it has been assumed that the Gilbert damping is an isotropic constant. In this study, we uncover a giant anisotropic Gilbert damping parameter of up to 431% in single-crystal thin films of epitaxial [100]-oriented yttrium iron garnet (YIG) using angle-dependent ferromagnetic resonance. In contrast, the Gilbert damping parameter of a [111]-oriented YIG film is almost isotropic. The observed anisotropic damping is shown to have a similar fourfold symmetry with magneto-crystalline anisotropy. The anisotropic spin-wave group velocity (vg), relaxation time (τ), and decay length (ld) were also experimentally evaluated through spin-wave spectra of [100]-oriented YIG thin film. We developed the LLG equation with the introduction of an anisotropic orbital Gilbert damping term. This anisotropic orbital damping originates from the crystal-field dominated anisotropic spin–orbit coupling and orbital-related magnon–phonon coupling. Our results extend the understanding of the mechanism of anisotropic Gilbert damping in single-crystal magnetic insulators with strong magneto-crystalline anisotropy. [ABSTRACT FROM AUTHOR]

The core of this research is to elucidate the effect of the particle size of the starting oxide on the dielectric properties of Zn 0.7 Mg 0.3 TiO 3 ceramics. The study was carried out using a conventional solid-state reaction route. The microstructure optimization of Zn 0.7 Mg 0.3 TiO 3 ceramics was achieved by introducing nanoscale particles. The distortion of octahedral [TiO 6 ] and the effect of crystal structure led to significant changes in the dielectric properties. Stability analysis shows that usage of nanoparticles decreases the temperature stability of Zn 0.7 Mg 0.3 TiO 3 ceramics. This work will offer a well-defined guideline for the selection of raw materials to prepare ceramics in the practical production process. [ABSTRACT FROM AUTHOR]

Antiferromagnetic oxides have attracted increasing attention for their outstanding peculiarities in spintronics. Crystal lattice defects that are present in antiferromagnetic oxides can influence their physical properties, such as vacancy‐induced ferromagnetism. Meanwhile, the generation and manipulation of ultrafast spin currents of antiferromagnetic insulators are highly desired. Although the generation and detection of terahertz spin current pulses in antiferromagnetic oxides have been realized, the effect of vacancy‐induced ferromagnetism on spin current in antiferromagnetic oxides is not yet known. Herein, the role of vacancy‐induced ferromagnetism on the terahertz spin current in antiferromagnetic nickel oxide thin films is reported. Structural and magnetic characterizations reveal that nickel vacancies effectively break the strong antiferromagnetic exchange coupling, giving rise to the coexistence of antiferromagnetism and ferromagnetism in NiO thin films. Notably, the enhancement of terahertz radiation associated with the photo‐induced ultrafast spin current of NiO thin film with the strongest ferromagnetism is the most significant. Besides, the nonlinear susceptibility tensor parameters related to the antiferromagnetic property of NiO thin films also change distinctly. The findings indicate that the defects of antiferromagnetic materials play a decisive role in the application of antiferromagnetic spintronics in the terahertz field. [ABSTRACT FROM AUTHOR]

A spin Hall effect (SHE) enables the electrical generation and detection of spin currents for promising applications in spintronics, but heavy metals with low spin Hall angle θSH limit the development of SHE devices. In this work, we have introduced dielectric oxide material SrTiO3 into Pt by magnetron sputtering and measured the θSH on the NiCo/Pt1–x(STO)x heterostructure through spin-torque ferromagnetic resonance. Our results demonstrate that the maximum spin Hall angle in Pt0.98(STO)0.02 is 0.121 ± 0.003, which is approximately twice that of pure Pt (0.064 ± 0.003). Moreover, theoretical analysis has revealed that the spin Hall angle arises from a complementary interplay between intrinsic and extrinsic mechanisms, namely, the strong spin–orbit coupling in Pt for the intrinsic mechanism and side-jump scattering caused by scalar potential and lattice expansion at dielectric impurities for the extrinsic mechanism. This interplay significantly contributes to enhancing the spin Hall angle. This work demonstrates an effective strategy for fabricating high-performance spin Hall materials with low resistivity, large spin Hall angle, and excellent compatibility with semiconductor processes in low-power spin-torque devices. [ABSTRACT FROM AUTHOR]

The growth of the CsI(Tl) scintillators deposited on glass substrates with proper wavelength matching the mainstream semiconductor circuits is crucial for X-ray imaging industry. But the coupling loss between the scintillators and silicon based photo sensors has limited the performance. So fabricating CsI(Tl) films on monocrystalline silicon is greatly important for next-generation high performance X-ray image devices. However, the lattice and thermal mismatch between CsI(Tl) and Si always deteriorates the morphology and structure, and thus degrades the property of the CsI(Tl) scintillation converters. Here, by utilizing crystalline graphene(Gr) as a buffer layer, the van der Waals epitaxial growth of CsI(Tl) film on Si(111) substrate is reported and its advanced applications are demonstrated. The introduced graphene buffer layer extremely frees the stress between CsI(Tl) and Si substrate. Therefore, the CsI(Tl) films show perfect micro-columnar and crystalline structures, and then, exhibit much higher light output and signal to noise ratio, and better modulation transfer functions and a bar pattern X-ray image compared to that on bare Si(111) substrate. This facile method not only lays the foundation for the epitaxy of the alkali halide crystals, including CsI(Tl), onto Si-based detectors and its applications in radiation detection, but also may broaden a new perspective of deposition of CsI(Tl) scintillators into flexible substrates. [ABSTRACT FROM AUTHOR]

Cr-doped BiFeO3 (BFCO) thin films were formed on Pt/Ti/SiO2/Si(100) substrates by chemical solution deposition, in which the nominal Fe/Cr ion ratio was changed from 100/0 to 40/60. The spin-coated, dried, and prefired films were finally crystallized in air, nitrogen, and oxygen flow mainly at temperatures below 500 °C. X-ray diffraction analysis revealed that polycrystalline grains of BiFeO3 (BFO) were formed in the films with ratios smaller than 80/20 after crystallization at 450 °C. It was also found from cross-sectional energy dispersive X-ray spectroscopy-scanning transmission electron microscopy (EDX–STEM) that Fe and Cr atoms mainly existed in different crystallites. On the basis of these results, a growth model in which the low-temperature crystallization of BFO is triggered by Bi7CrO12.5 crystallites is proposed. The leakage current density and remanent polarization (Pr) in BFCO films increased with increasing Fe ratio, and a large Pr of 60 µC/cm2 was obtained in a 450 °C-crystallized BFCO film with the 80/20 ratio measured at 1.6 MV/cm and 10 kHz. In the 500 °C-crystallized BFCO films with a Cr doping ratio of more than 50 at. %, a Pr close to the initial value was obtained even after 108 switching cycles owing to the reduced leakage current density. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a toxic heavy metal, exposure to which leads to adverse health effects including chronic kidney damage. Tremendous efforts have been explored in identifying safe chelating agents for removing accumulated Cd from kidney, but with limited success owing to their associated side effects and the ineffectiveness in eliminating Cd. A newly developed chelating agent, sodium (S)-2-(dithiocarboxylato((2S,3 R,4R,5 R)-2,3,4,5,6-pentahydroxyhexyl) amino)-4(methylthio)butanoate (GMDTC), has been shown to effectively mobilize Cd from kidney. However, the mechanism(s) of removal are unclear, while it has been hypothesized that renal glucose transporters potentially play key roles mainly because GMDTC contains an open chain glucose moiety. To test this hypothesis, we utilized the CRISPR/Cas9 technology and human kidney tubule HK-2 cells, and constructed sodium-dependent glucose transporter 2 (SGLT2) or glucose transporter 2 (GLUT2) gene knockout cell lines. Our data showed that GMDTC's ability in removing Cd from HK-2 cells was significantly reduced both in GLUT2 −/− or SGLT2 −/− cells, with a removal ratio reduced from 28.28% in the parental HK-2 cells to 7.37% in GLUT2 −/− cells and 14.6% in SGLT2 −/− cells. Similarly, knocking out the GLUT2 or SGLT2 led to a compromised protective effect of GMDTC in reducing cytotoxicity of HK-2 cells. This observation was further observed in animal studies, in which the inhibition of GLUT2 transporter by phloretin treatment resulted in reduced efficiency of GMDTC in removing Cd from the kidney. Altogether, our results show that GMDTC is safe and highly efficient in removing Cd from the cells, and this effect is mediated by renal glucose transporters. [ABSTRACT FROM AUTHOR]

Magnons have demonstrated enormous potential for next‐generation information technology, namely the ability to build quasiparticle low‐power integrated circuits without the moving of electrons. An experimental bosonic magnon transistor with multifunction, low‐loss, and full‐wavelength control of propagating spin waves (magnon current) is developed in this work. Using a monolayer of graphene as the high‐efficiency thermal phonon source and a low‐loss electrically insulating ferrimagnetic single‐crystalline yttrium iron garnet film as the propagating spin‐wave channel, the presented transistor has three functioning regions of spin‐wave modulation at full wavelength: prominent amplification, complete cut‐off, and linear phase shift. The magnon‐phonon‐mediated nonequilibrium state created by the temperature gradient in this transistor works in two ways: when the thermal phonon flow is small, the positive thermal spin‐torque induced by the longitudinal spin‐Seebeck effect amplifies spin waves; when the thermal phonon flow is large, the magnon–magnon interaction due to nonequilibrium thermal magnon injection greatly contributes to spin‐wave cut‐off. Furthermore, linear adjustment of the spin‐wave phase by creating a thermal phonon bath is demonstrated. These findings reveal that the numerous magnon–phonon coupling mechanisms in magnetic insulators offer a promising platform for the implementation of reconfigurable magnonic transistors. [ABSTRACT FROM AUTHOR]

Background: Hematopoietic stem cells are able to self-renew and differentiate into all blood cell lineages. Hematopoietic stem cell transplantation is a mainstay of life-saving therapy for hematopoietic malignancies and hypoproliferative disorders. In vitro hematopoietic differentiation of human pluripotent stem cells (hPSCs) is a promising approach for modeling hematopoietic development and cell replacement therapies. Although using hPSCs to derive hematopoietic progenitor cells has achieved some successes in the past, differentiation from hPSCs to produce all hematopoietic cells which can provide robust long-term multilineage engraftment is still very difficult. Here, we reported a novel culture system for hematopoietic differentiation from human embryonic stem cells (hESCs) with optimal cytokines combinations under hypoxia condition. Methods: In vitro production of T lineage hematopoietic stem/progenitor cells from hESCs by using hypoxia differentiation system, the effects and the potential mechanism of hypoxia promoting T lineage hematopoiesis were investigated by RT-qPCR validation, cell cycle assay and flow cytometry analysis. Results: Using our differentiation system, almost 80% CD45+ cells generated from hESCs were hematopoietic cells and particularly could be further induced into CD3+TCRαβ+ T cells in vitro. We detected more CD34+CD144+ hematopoietic endothelial progenitors (HEPs) induced from hESCs than those in normoxia conditions, and the early HEPs-related gene DLL4 was upregulated by enhancing the hypoxia signaling via potential HIF-1α/NOTCH1/DLL4 axis to enhance arterial feature, thus drove T lineage during the hematopoiesis. Strikingly, hematopoietic cells generated in our system exhibited the potential for all multilineage reconstruction including lymphoid, myeloid and erythroid lineages in vivo by transplantation assay. Conclusion: Our results demonstrated that hypoxia plays an important role in T lineage hematopoiesis by promoting the expression of arterial endothelial gene DLL4 and upregulation of NOTCH1 through the activation of the HIF-1α signaling pathway. These results provide a significant approach for in vitro and in vivo production of fully functional hematopoietic stem/progenitor cells from hESCs. [ABSTRACT FROM AUTHOR]

The isotropic transmission of magnetostatic forward volume spin waves in magnetic films with perpendicular magnetic anisotropy (PMA) is shown to be useful in the implementation of magnon-based micro-conduits. However, to our knowledge, non-magnetic-bias-field spin-wave propagation in a PMA magnetic insulator has not been achieved yet, which constrains the development of magnonic information devices and systems. Herein, we demonstrate a robust, bias-free spin-wave transmission in an 18.5-μm-thick bismuth-doped thulium iron garnet film with PMA. This ferrimagnetic film grown by liquid phase epitaxy exhibits high quality in both its crystal structure and its chemical composition and displays a large PMA field of ∼173 mT. The bias-free and reciprocal propagation of spin waves is demonstrated by all-electrical spectroscopy and provides a group velocity of 4.90 km s−1 and a decay length of 20.5 µm at zero magnetic field. Direct imaging of the remnant state indicates that the bias-free spin waves propagate along the oppositely oriented stripe domains with Bloch-type walls, which are formed by in-plane pre-magnetization. Our work contributes to the construction of isotropic charge-free micro-circuits with high levels of integration and nonvolatility. [ABSTRACT FROM AUTHOR]

Background: Human pluripotent stem cells (hPSCs) have great potential in applications for regenerative medicine and drug development. However, 3D suspension culture systems for clinical-grade hPSC large-scale production have been a major challenge. Accumulating evidence has demonstrated that the addition of dextran sulfate (DS) could prevent excessive adhesion of hPSCs from forming larger aggregates in 3D suspension culture. However, the signaling and molecular mechanisms underlying this phenomenon remain elusive. Methods: By using a cell aggregate culture assay and separating big and small aggregates in suspension culture systems, the potential mechanism and downstream target genes of DS were investigated by mRNA sequence analysis, qRT-PCR validation, colony formation assay, and interference assay. Results: Since cellular adhesion molecules (CAMs) play important roles in hPSC adhesion and aggregation, we assumed that DS might prevent excess adhesion through affecting the expression of CAMs in hPSCs. As expected, after DS treatment, we found that the expression of CAMs was significantly down-regulated, especially E-cadherin (E-cad) and intercellular adhesion molecule 1 (ICAM1), two highly expressed CAMs in hPSCs. The role of E-cad in the adhesion of hPSCs has been widely investigated, but the function of ICAM1 in hPSCs is hardly understood. In the present study, we demonstrated that ICAM1 exhibited the capacity to promote the adhesion in hPSCs, and this adhesion was suppressed by the treatment with DS. Furthermore, transcriptomic analysis of RNA-seq revealed that DS treatment up-regulated genes related to Wnt signaling resulting in the activation of Wnt signaling in which SLUG, TWIST, and MMP3/7 were highly expressed, and further inhibited the expression of E-cad. Conclusion: Our results demonstrated that DS played an important role in controlling the size of hPSC aggregates in 3D suspension culture by inhibiting the expression of ICAM1 coupled with the down-regulation of E-cad through the activation of the Wnt signaling pathway. These results represent a significant step toward developing the expansion of hPSCs under 3D suspension condition in large-scale cultures. [ABSTRACT FROM AUTHOR]

Abstract: Nb-doped Z-type hexaferrites (Ba3(Co0.4Zn0.6)2Fe24O41) with composition of Ba3(Co0.4Zn0.6)2Fe24O41+x Nb2O5 (where x=0.0, 0.1, 0.2, 0.4, 0.6, 0.8, 1.2, 1.6 and 2.0wt%) were prepared by a solid-state reaction method. The effects of different sintering temperature (T s) and Nb2O5 content on the sintering behaviors, phase composing, microstructure, and magnetic properties of the samples were investigated. The results from X-ray diffraction and scanning electron microscopy show that as the amount of Nb2O5 additive increases, the major phase changes to Z-phase, Simultaneously, M-phase and a small amount of niobate phase appear. The Nb2O5 additive promotes the grain growth as reaction center at lower sintering temperature (1220°C), but at higher temperature (1260°C), niobate phase separated out in grain boundaries as secondary phase will restrain abnormal grain growth, so closed pores in grains are not formed. The Nb2O5 additive can enhance densification, improve initial permeability of hexaferrites by increasing the grain growth of hexaferrite and the displacement of ions in the sintering process due to the aberration and activation of crystal lattice, which is accompanied by the solubility of Nb5+ in the hexaferrites. A relative density of 96%, maximum initial permeability (32–33), minimum coercivity (454–455A/m) and resonance frequency above 400MHz were obtained for the sample with 0.8wt% Nb2O5 sintered at 1260°C for 6h. [Copyright &y& Elsevier]

Wet chemical methods have demonstrated their unparalleled success to control the size and size distribution of colloidal nanoparticles. In a wet chemical nanoparticle synthesis, precursor reaction, nucleation and growth will occur, not subsequently but often concurrently. The three processes can thus strongly affect each other during the nucleation. Here mathematical models were used to simulate the rate of the concurrently occurring precursor reaction, nucleation and growth. For both the 'hot-injection' and 'heat-up' methods, the simulation has clearly revealed how the batch nanoparticle products be determined by the interplay of the three processes. The simulation shows that the competition between nucleation and growth determine the size, size distribution, and concentration of batch colloidal nanoparticles, where the dominance between the two can be varied by synthetic conditions. By comprehensively considering the interplay, the nanoparticle synthesis in solution can be much better understood, which benefits the fine design of the synthesis to make desired batch nanoparticles. [ABSTRACT FROM AUTHOR]

A fully integrated 3-D Hall magnetic sensor with dual active structure was proposed. Results by technology computer-aided design simulation show that the proposed sensor provides a doubled magnitude improvement in sensitivity of vertical magnetic field direction and maintains a good level sensing of horizontal magnetic field direction compared with the sensor with single active layer. The designed sensor was fabricated by wet etching process and a method of preparing Ohmic contacts on the "pseudo-sidewalls" is proposed. The measurements show that the non-linearity does not exceed 0.5% and a voltage sensitivity of up to 0.046 T−1, which matches the simulation results. The proposed sensor boasts a simplified structure that allows for fabrication using different layers only through a planar process, which makes it more conducive to the integration of devices and systems. [Display omitted] • Manufacturing of sensors is based entirely on planar processes. • Vertical sensing sensitivity is improved compared to some HG series products. • A method of preparing Ohmic contacts on the "pseudo-sidewalls" is proposed. [ABSTRACT FROM AUTHOR]

Highlights: [•] The Ni3+ concentration decreased in the films as the annealing temperature rised. [•] The filaments were composed with Ni or/and oxygen vacancies affected by Ni3+. [•] Resistance switching characteristics is effected by Ni3+ concentration obviously. [Copyright &y& Elsevier]

Soft-magnetic high-entropy alloy (HEA) Fe 33 Co 28 Ni 28 Ta 5 Al 6 were prepared by laser-melting deposition (LMD). The microstructures and mechanical as well as magnetic properties of the fabricated samples were investigated. All samples comprised face- and body-centered cubic phases, where the proportion of the latter increased when the laser power was increased from 800 to 1400 W. With the increasing laser power, the yield strengths of the samples decreased slightly, and the saturation magnetization (B S) of the samples remained at approximately 1.07 T, the coercivity increased from 1034 A/m to 4456 A/m. The study showed that high laser powers resulted in high stress levels and increased the blocking effect on the motion of the magnetic domain walls of the samples. This work would provide a path way for the rapid manufacturing of high-performance soft-magnetic HEAs. • Prepared a soft-magnetic high-entropy alloy via laser-melting deposition (LMD). • Obtained a soft-magnetic material with good yield strength (1380 MPa) at a laser power of 800 W. • The mechanical and magnetic properties of the alloy can be improved via adjusted the laser powders. [ABSTRACT FROM AUTHOR]

Adjusting the phase composition of high-entropy alloys is an effective approach to change its mechanical and magnetic properties. In this study, FeCoNiCr high-entropy alloys with Al addition (Al x FeCoNiCr; x = 0.0, 0.25, 0.5, 0.75, 1.0, 1.25, 1.75) were prepared by argon arc melting to obtain a special spinodal decomposition structure. There precipitated body-centered cubic (BCC) phase in the face-centered cubic (FCC) phase matrix for the samples with Al (x = 0.25, 0.5, 0.75) addition. Furthermore, the increase in the Al content (x = 1.0, 1.25, 1.75) transformed the alloy into a BCC phase, and resulted in a spinodal decomposition in the alloy. This spinodal decomposition created a low-misfit coherent nanostructure combining the enriching AlNiCo ordered B2 matrix with enriching Fe–Cr BCC disordered nanoprecipitates. The difference in the distribution of chemical elements of the two phases leads to different magnetic properties and induces the magnetoresistance (MR) effect. This provides a pathway for the design of advanced functional high-entropy alloys. [Display omitted] • Spinodal decomposition can induce magnetoresistance (MR) in AlFeCoNiCr alloy. • The magnetic and nonmagnetic phase is necessary condition for inducing MR effect. • The mechanical and MR properties can be controlled by spinodal decomposition. [ABSTRACT FROM AUTHOR]

In the present work, Li 0.35 Zn 0.30 Mn 0.05 Ti 0.15 Fe 2.15 O 4 ferrites were successfully synthesized via solid-state reaction method with the assistance of Bi 2 O 3 -MgO mixture. It was observed that a pure spinel phase could be formed at low temperatures (880 °C–920 °C), suggesting the compatibility of co-firing with silver internal electrodes. The employment of Bi 2 O 3 -MgO mixture could not only achieve the low-temperature sintering, but also facilitate the grain growth and subsequently promote the magnetic properties. SEM results revealed that the ferrites grain size was significantly increased (from 1 to 20 μm) with an appropriate dopant addition (1.2 wt %). Meanwhile, the saturation induction was enhanced from 141.2 to 345.9 mT, the coercivity was decreased from 515.2 to 176.6 A/m, and the FMR linewidth was dramatically decreased from 749.0 to 245.0 Oe at 9.3 GHz. Thus it is expected that the improved properties will allow the Li 0.35 Zn 0.30 Mn 0.05 Ti 0.15 Fe 2.15 O 4 ferrites to be a promising candidate for low temperature co-fired ceramics (LTCC) applications. Image 1 • Low-temperature preparation of LiZn ferrites (below 950 °C). • All the samples with Bi 2 O 3 -MgO mixture show a typical spinel structure. • Bs increased from 141 to 345 mT with the ΔH decreased from 749 to 245 Oe. [ABSTRACT FROM AUTHOR]

In this work, high quality yttrium-iron-garnet (YIG) thin films were fabricated on a Ga 3 Gd 5 O 12 substrate by pulsed laser deposition (PLD). The material composition, iron ion valences and magnetic properties of the YIG films were systematically investigated as a function of annealing temperature. X-ray diffraction and Raman spectroscopy measurements demonstrate optimal YIG film crystallinity when annealed at 800 °C. X-ray photoelectron spectroscopy confirms the Fe2+ ions were strongly suppressed in YIG thin film after annealed at 800 °C. In this case, 60 nm-thick YIG films exhibit excellent magnetic properties having bulk-like saturated magnetization (1755 Gs), a minimized ferromagnetic resonance linewidth (8.3 Oe) and a low Gilbert damping parameter of 5.76 × 10−4. Our study prove that suitable annealing conditions play a critical role on garnet composition, iron ion valences and magnetic properties for PLD grown high quality YIG thin films, which have great potential in the fabrication of low dissipative spintronic devices. • Annealing plays a critical role on microstructure and magnetic properties of YIG film. • The increase of Fe2+ iron contents lead to additional absorption peaks in the FMR spectra. • 800 °C annealed films own the optimal element ratio and the Fe3+ iron contents. • Surface roughness and crystallinity have great influence in achieving a low damping. [ABSTRACT FROM AUTHOR]

Although there are many new scintillators being developed recently, CsI: Tl is still a very efficient one among them. However it suffers from afterglow which limits application in high-speed x-ray imaging. In order to find out the mechanism of afterglow and the method to suppress afterglow in CsI: Tl, the theoretical model of perfect CsI, CsI: Tl and CsI: Tl, Eu are built by the software Material Studio. The total and partial density of states of these three models is calculated within the framework of generalized gradient approximation and ultra-soft pseudo-potential. The results indicate that the generation of afterglow in CsI: Tl is due to the impurity energy bands introduced by Tl. Moreover, co-doping CsI: Tl with Eu will introduce deeper impurity energy bands which can effectively scavenge the electrons trapped by the shallow impurity energy bands introduced by Tl, thus suppressing the afterglow in CsI: Tl. [ABSTRACT FROM AUTHOR]

Highlights • The morphology and scintillation properties of the CsI(Tl) films were researched. • We studied the growth mechanism of the CsI(Tl) films on glass and Si(1 1 1) substrates. • We built the growth model of the CsI(Tl) films based on the Volmer-Weber growth mode. • We modelled the micro-columns for the CsI(Tl) film with a larger thickness. Abstract The microstructure morphology and crystal quality of CsI(Tl) films are influenced by the crystal properties of substrates. In this work, CsI(Tl) films on the glass and single crystal silicon substrates are fabricated by vacuum thermal evaporation at a low deposition rate. The microstructure morphology, crystalline quality and scintillation properties of the films were examined by using scanning electron microscopy, X-ray diffraction, photoluminescence and radioluminescent spectrum. To study the growth mechanism of CsI(Tl) films on amorphous and monocrystalline substrates, a growth model based on the classical Volmer-Weber (VW) growth mode are proposed. During the film growing, the wetting and not-wetting phenomena of the clusters appear on the glass and Si(1 1 1) substrates respectively. In addition, the microcrystalline columns with different orientations are modeled to explain the surface morphology deteriorate of the CsI(Tl) film with 3 μm thickness on Si(1 1 1) substrate. [ABSTRACT FROM AUTHOR]

Abstract Gilbert damping enhancement induced by the spin pumping effect is investigated in Y 3 Fe 5 O 12 (YIG)/heavy metal bilayers. Because its spin polarization is high and Gilbert damping is low, Co 2 FeAl 0.5 Si 0.5 (CFAS) is deemed a promising ferromagnetic material in spintronics devices. We studied microwave dynamic magnetizations in YIG/CFAS bilayers combined with ferromagnetic resonance measurement using a vector network analyzer to reveal a 5-fold giant damping enhancement compared with that for the YIG/Pt bilayers. This phenomenon was attributed to both the exchange coupling effect and spin pumping effect. By inserting a 10-nm Cu spacer, direct exchange coupling can be suppressed. A spin mixing conductance g e f f ↑ ↓ of 7.75 × 1018m−2 generated by spin pumping was obtained. The study provides an effective approach to tailor the damping in magnetic thin films. Highlights • The Gilbert damping in YIG capped by CFAS increased significantly. • The damping derived from exchange coupling and spin pumping effect between the YIG film and CFAS layer. • The spin inject efficiency in YIG/CFAS interface is higher than YIG/Pt bilayers. [ABSTRACT FROM AUTHOR]

Immunochromatographic strips (ICSs) are inexpensive, simple, portable, and robust, and therefore have many uses in the medicinal, agricultural, and environmental industries. For detection of small molecules, current ICSs are competitive format (competitive ICSs, CICSs), which only offer a turn-off readout mode, and therefore lead to low sensitivity when evaluating results by the naked eye. To overcome this problem, we report a turn-on CICSs that relies on the ability of gold nano-stars (AuNSs) quenching the signal of quantum dots (QDs). This turn-on CICSs device was applied to detect cadmium ions (Cd 2+ ). The linear detection range (LDR) of the turn-on CICSs was 0.25 ng/mL-8 ng/mL, and the detection of limit (LOD) was 0.18 ng/mL. Compared with traditional turn-off CICSs, the sensitivity of the turn-on CICSs was enhanced by 32 times. The turn-on CICSs also has a high specificity and high recovery for the detection of Cd 2+ in Pearl River (95–112%) and tap water samples (103.5–116.67%). Therefore, we believe the turn-on CICSs offers great potential for the detection of other small molecules in clinical diagnostics, food safety investigations, and environment pollution monitoring. [ABSTRACT FROM AUTHOR]

Wrinkled graphene shows an enhanced photoelectric effect owing to the opening of a bandgap induced by stress. Here, bismuth (Bi) nanorods array with trigonal orientation are assembly grown on silicon substrates by molecular beam epitaxy. Single layer graphene (SLG) is transferred on top of the Bi nanorods array to make flat SLG forming into wrinkles. Through the application of visible-infrared and Fourier transform infrared spectroscopies, enhanced optical absorption in the wrinkled SLG/Bi nanorod heterostructures was observed. Raman spectral analysis showed a large 2D peak shift of up to −11 cm −1 compared with that of flat graphene on silicon wafers. This finding indicates the existence of a tensile stress induced opening of the band gap. Nonlinear current-voltage characteristics confirmed the opening of an intrinsic bandgap in the wrinkled graphene. The on-off ratio was shown to increase by 30 times and the dark current was remarkably suppressed by 3–4 orders of magnitude for the Bi nanorods/wrinkled SLG heterostructures when compared with those properties of flat SLG on silicon. [ABSTRACT FROM AUTHOR]

Although many new scintillation materials are developed, CsI:Tl is still prevailing because of its high scintillation efficiency. In this work, CsI:Tl thin films were fabricated by vacuum thermal evaporative deposition method and their morphology properties and growth orientation were observed by SEM and XRD. Photoluminescent spectra were used to measure the luminescent properties of the CsI:Tl thin film. The results show us the film formation process of CsI:Tl thin film and analyze the effect of film formation process and the deposition rate on the orientation of the CsI:Tl thin film. [ABSTRACT FROM AUTHOR]

Tuning the magnetic anisotropy of nanoparticle assemblies is critical for their applications such as on-chip magnetic electronic components and electromagnetic wave absorption. In this work, we developed a facile hierarchical self-assembly method to separately control the magnetic shape and magnetocrystalline anistropy of individual nanoparticle assemblies in arrays. Since magnetic nanoparticle assemblies in the array have the same size, shape and alignment, we are able to study the magnetic properties of individual nanoparticle assembly by measuring the whole arrays. The interplay between the two magnetic anisotropies was systematically studied for disk- and bar-shaped nanoparticle assemblies. Maximum magnetic anisotropy was obtained when the easy axis of magnetic nanoparticles was aligned along the long axes of the bar-shaped nanoparticles assemblies. [ABSTRACT FROM AUTHOR]

Although there are many new scintillators being developed recently, CsI: Tl is still very efficient among them. The fluorescent lifetime is a very important parameter of CsI: Tl thin film and two series of experiments have been conducted to learn about it. Our experiments, however, have demonstrated that the deposition rate and the codoping of Eu 2+ will significantly influence its fluorescent lifetime. In order to increase the efficiency of the imaging system, we intend to obtain a higher fluorescent lifetime for CsI: Tl thin film by controlling these two conditions. [ABSTRACT FROM AUTHOR]

A series of CoFe/IrMn exchange bilayers was grown by DC-sputtering at different ultra-low argon pressures ranging from 0.008 to 0.1 Pa. This pressure range was one to two orders lower than the normal sputtering pressure. Results revealed that the exchange bias increased from 140 to 250 Oe in CoFe(10 nm)/IrMn (15 nm) bilayers of fixed thickness because of the improved crystalline structure and morphological uniformity of films. Since ferromagnetic /antiferromagnetic (FM/AF) bilayers are always used in linear magnetic sensors as detection layers, the varying exchange bias can successfully achieve tunable linear range in a crossed pinning spin valve. The linear range could be adjustable from −80 Oe – +80 Oe to −150 Oe – +150 Oe on the basis of giant magnetoresistance responses. Therefore, this method provides a simple method to tune the operating range of magnetic field sensors. [ABSTRACT FROM AUTHOR]