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An optical microfiber with nanointerface is developed for single-molecule detection and cellular photothermal therapy., For early-stage diagnostics, there is a strong demand for sensors that can rapidly detect biomarkers at ultralow concentration or even at the single-molecule level. Compared with other types of sensors, optical microfibers are more convenient for use as point-of-care devices in early-stage diagnostics. However, the relatively low sensitivity strongly hinders their use. To this end, an optical microfiber is functionalized with a plasmonic nanointerface consisting of black phosphorus–supported Au nanohybrids. The microfiber is able to detect epidermal growth factor receptor (ErbB2) at concentrations ranging from 10 zM to 100 nM, with a detection limit of 6.72 zM, enabling detection at the single-molecule level. The nanointerface-sensitized microfiber is capable of differentiating cancer cells from normal cells and treating cancer cells through cellular photothermal therapy. This work opens up a possible approach for the integration of cellular diagnosis and treatment.

In this study, species compositions, distributions, and diversity patterns of fish assemblages were investigated at 50 sampling sites in the Weihe River and its two largest tributaries, the Jinghe River and the Beiluo River, under high- and low-flow conditions in 2017. For every condition tested and in the all rivers tested, Cyprinidae was the richest family, containing 17 of the 39 identified fish species. Carassius auratus was the most common species, accounting for 11.3% of the total individuals. Nonmetric multidimensional scaling (NMDS), analysis of similarities (ANOSIM), and similarity percentage analysis (SIMPER) revealed that fish species composition differed significantly among rivers (p &lt, 0.05), with dissimilar species assemblages found in the different rivers. Variation was influenced by a combined effect of habitat conditions, environmental factors, and human impact. Canonical correspondence analysis (CCA) identified variables explaining the variation in fish species (p &lt, 0.05), and elevation contributed the most under both flow conditions. Alpha diversity decreased with increasing elevation within rivers as a result of changing environmental conditions, especially for wetted width. Alpha and beta diversities of rivers increased with increasing drainage area, which is related to habitat heterogeneity. The decrease in alpha diversity and the increase in beta diversity with increasing elevation can be explained by variations in habitat and geographic features.

In this paper, we present a series of methods to improve the performance of spoken language understanding in the 1st Chinese Audio-Textual Spoken Language Understanding Challenge (CATSLU 2019) which is aimed to improve the robustness for automatic speech recognition (ASR) errors and to solve the problem of not enough labeled data in new domains. We combine word information and char information to improve the performance of the semantic parser. We also use some transfer learning methods like correlation alignments to improve the robustness of the spoken language understanding system. Then we merge the rule method and the neural network method to raise system output performance. In video and weather domains with few training data, we use both the transfer learning model trained on multi-domain data and the rule-based approach. Our approaches achieve F1 scores of 86.83%, 92.84%, 94.16%, and 93.04% on the test sets of map, music, video and weather domains.

Central and peripheral nerve injuries pose a great threat to people. Complications such as inflammation, muscle atrophy, traumatic neuromas and delayed reinnervation can bring huge challenges to clinical practices and barriers to complete nerve regrowth. Physical interventions such as electrical and magnetic stimulation show satisfactory results with varying parameters for acute and chronic nerve damages. The biological basis of electrical and magnetic stimulation mainly relies on protein synthesis, ion channel regulation and growth factor secretion. This review focuses on the various paradigms used in different models of electrical and magnetic stimulation and their regenerative potentials and underlying mechanisms in nerve injuries. The combination of physical stimulation and conductive biomaterial scaffolds displays an infinite potentiality in translational application in nerve regeneration.

The activation or functionalization of the saturated C-H is an extremely active field at present. We have explored the triplet state thioxanthone in reactivity of the hydrogen transfer reaction between donors and acceptors. In our works, two donors with quasi-inert sp

Micro-CT is a nondestructive scanning device that is capable of capturing three dimensional structures at _m level. With the spread of this device uses in medical fields, it is expected that this device may bring further understanding of the human anatomy by analyzing three-dimensional micro structure from volume of in vivo specimens captured by micro-CT. In the topic of micro structure analysis of lung, the methods for extracting surface structures including the interlobular septa and the visceral pleura were not commonly studied. In this paper, we introduce a method to extract sheet structure such as the interlobular septa and the visceral pleura from micro-CT volumes. The proposed method consists of two steps: Hessian analysis based method for sheet structure extraction and Radial Structure Tensor combined with roundness evaluation for hollow-tube structure extraction. We adopted the proposed method on complex phantom data and a medical lung micro-CT volume. We confirmed the extraction of the interlobular septa from medical volume from experiments.

Background Sucrose allyl ether (SAE) containing hemostatic drugs and a photoinitiator was established to treat mild postpartum hemorrhage or long-term continuous abnormal uterine bleeding in minimally invasive surgery (MIS) using a photopolymerization method. Methods and results Real-time infrared spectroscopy and rheological experiments showed that the SAE monomer with shear-thinning characteristics could polymerize rapidly into a transparent membrane. Cytotoxicity experiments in vitro showed that this system could elicit a long-term hemostatic effect. Tissue adhesion was also evaluated. The photo-stability of four delivered antifibrinolytic drugs (6-aminocaproic acid, ethylenediaminediacetic acid, tranexamic acid and p-(aminomethyl) benzoic acid) was tested by ultraviolet-photolysis experiments and illustrated by time-dependent density functional theory. Sustained-release experiments revealed that the formed film could be used as a drug carrier. Molecular docking and molecular dynamics were done to investigate the binding mechanism between hemostatic drugs as ligands and the human plasminogen kringle-1 (1HPK) as a target. Conclusion It has been suggested that SAE with tranexamic acid could be a drug-release system of microchannel transport used in MIS. This system could tackle the dilemma of fluidity and adhesion in MIS. The photo-stable tranexamic acid was the most suitable drug according to its satisfactory binding energy, good photo-stability, and sustained release.

Conventional digital core reconstruction methods are not suitable for deep shale gas reservoirs with low porosity and permeability, anisotropy and complex mineral composition, and conventional single resolution three-dimensional digital core structure model cannot fully describe the core structure of shale gas reservoirs of different scales. In this paper, the advantages and disadvantages of different digital core reconstruction methods are summarized by analyzing examples. It is found that MCMC core reconstruction method is more suitable for image reconstruction of 3D digital structure model core of deep shale gas reservoir in China; Finally, in view of the problems existing in conventional digital core reconstruction methods, combining CT imaging with ion beam focused electron microscopy (FIB-SEM) imaging technology, a 3D digital core structure model with multi-scale, multi-component and corresponding macro pore and micro pore of the corresponding reservoir is proposed. The micro spatial distribution structure of the model is similar to that of real shale gas reservoir core, it overcomes the difficulty that the resolution of single scale 3D digital gas reservoir core model and the micro size characteristics of gas reservoir core cannot be perfectly considered. It can not only accurately describe the micro pore space distribution structure of real core gas reservoir, but also accurately describe the macro heterogeneity of deep shale gas reservoir core.

The objective of this investigation is to predict the size-dependent dynamic stability of truncated conical microshells made of a functionally graded material (FGM) integrated with magnetostrictive facesheets. The microshells are subjected to a combination of axial compressive load and magnetic field in the presence of the nonlocality and strain gradient size dependencies. The conical microshells are assumed to be surrounded by a two-parameter Winkler-Pasternak medium augmented via a Kelvin-Voigt viscoelastic approach taking a nonlinear cubic stiffness into account. The nonlocal strain gradient-based differential equations of motion are constructed based upon the third-order shear deformation conical shell theory including the magnetic permeability tensor together with the magnetic fluxes. The discretization process within the framework of the generalized differential quadrature technique is employed to achieve the nonlocal strain gradient-based load-frequency responses. It is found that increasing the material gradient index results in to decrease the nonlocal strain gradient frequency obtained for a specific value of the axial compression within the prebuckling regime. However, within the postbuckling domain, an increment in the value of the material gradient index plays an opposite role. Also, the gap between the load-frequency curves associated with various material gradient indexes are more prominent for the nonlocal strain gradient cases in comparison with the classical one.

We prepared a splicing structure by using electron beam lithography, in which Pt and Ta were spliced together as the spin source upon perpendicularly magnetized Pt/Co/Pt heterostructures. It is found that Pt and Ta can modulate both spin–orbit torque and Dzyaloshinskii–Moriya interaction on the same magnetic layer, respectively. The four-state magnetization switching is achieved with the combinations of two spliced parts, which is observed by using a magneto-optical Kerr microscope. The initial nucleation position determines the chirality. The Pt side stabilizes a right-hand Neel domain wall and the Ta side stabilizes a left-hand Neel domain wall. Our study provides a method for further increasing the storage density and studying spin–orbit torque laterally.

Alloying a heavy metal (HM) layer is a useful approach to enhance the current-spin converting efficiency ξSH while keeping a relatively low resistance for spin–orbit torque (SOT) based devices. In this work, we report the enhancement of ξSH and nonlinear modification of the Dzyaloshinskii–Moriya interaction (DMI) by alloying Pt with Cr in a Pt100-xCrx/Co/AlOx trilayer. The maximum of ξSH is found at the composition of Pt75Cr25. At the compositions of Pt75Cr25 and Pt50Cr50, the DMI constant |D| is strongly shifted in the opposite sign, implying ferromagnetic coupling and antiferromagnetic coupling existing in the heavy metal layer can both influence the DMI. Finally, the current-driven switching behavior is observed by the magneto-optical effect. This work shows that adjusting the composition of the magnetic alloyed HM layer is an efficient approach to obtain an optimized SOT performance.

Although several synthetic polypeptide-based nano-prodrugs (NPDs) have entered clinical trials for cancer treatment, achieving a highly effective production of the NPDs for clinical translation remains a challenge. Herein, we develop a typical preparation of pH/glutathione (GSH) dual-responsive glycopolypeptide analogue NPDs having a high drug capsulation/loading efficiency of ca. 93% and ca. 27% even based on ring-opening polymerization (ROP) of a novel and general furan-containing N-carboxyanhydride (NCA) monomer, which facilitates the Diels-Alder (D-A) side-chain functionalization by maleimide modified chemotherapy drug without using any reactive additives. High reactivity of the D-A reaction resulting in the high preparation efficiency of the NPDs is confirmed by 1H NMR and density functional theory (DFT) calculations. The self-assembled properties as well as the dual-responsiveness of the NPDs are systemically studied by particle size and zeta potential assay, transmission electron microscopy and drug-delivery dynamics. The cell uptake mechanism, intracellular drug distribution, in vitro/vivo antitumor activity evaluations and the main organ damages of the NPDs are all investigated. Our work can provide a good solution to solve the inefficient fabrication of the smart synthetic polypeptide-based micelles for cancer treatment by following this general and sophisticated platform.

The spin pumping effect of CoFeB/Ir bilayers has been investigated via the broadband ferromagnetic resonance measurement. With increasing the thickness of heavy metal Ir layer, the Gilbert damping factor of 8 nm CoFeB film increases from 7 × 10−3 to 1.1 × 10−2, and the additional damping factors induced by the spin pumping effect quickly reaches its saturation value. According to the spin pumping theory, the spin mixing conductance of CoFeB/Ir and the spin diffusion length of Ir were obtained. The spin mixing conductance is 2.14 × 1019 m−2. Furtherly, the spin diffusion length is only 1.34 nm, which is quite shorter compared with the heavy metal Pt. Our results reveal the existence of the strong spin-orbit coupling in the heavy metal Ir, which can be a potential material for the application in spintronic devices.

An activation strain model was used to reveal the behavior of interaction, which was divided into four types as it proceeded from the reaction complex to the saddle point. For the 1,3-dipolar cycloaddition reaction, the interaction remained nearly zero at the first stage, but then decreased dramatically to become negative in the final stage. For the hydrogen atom transfer reaction, it started with a large positive value, which then fell to zero in the end. For Sn2 reaction, it decreased asymptotically from the beginning to the end. For the free radical addition reaction, meanwhile, it began on a zero point and climbed steadily up to a high positive value, but then decreased slightly at the saddle point. The use of an independent gradient model reveals a weak interaction containing both attractive and repulsive forces. These four types of behavior are the result of a compromise/balance between attraction and repulsion forces.

RNA interference (RNAi) is a biological process through which gene expression can be inhibited by RNA molecules with high selectivity and specificity, providing a promising tool for tumor treatment. Two types of molecules are often applied to inactivate target gene expression: synthetic double stranded small interfering RNA (siRNA) and plasmid DNA encoding short hairpin RNA (shRNA). Vectors with high transfection efficiency and low toxicity are essential for the delivery of siRNA and shRNA. In this study, TDAPEI, the synthetic derivative of low-molecular-weight polyethylenimine (PEI), was cross-linked with imine bonds by the conjugation of branched PEI (1.8 kDa) and 2,5-thiophenedicarboxaldehyde (TDA). This biodegradable cationic polymer was utilized as the vector for the delivery of plasmid DNA expressing anti-VEGF-shRNA. Compared to PEI (25 kDa), TDAPEI had a better performance since experimental results suggest its higher transfection efficiency as well as lower toxicity both in cell and animal studies. TDAPEI did not stimulate innate immune response, which is a significant factor that should be considered in vector design for gene delivery. All the results suggested that TDAPEI delivering anti-VEGF-shRNA may provide a promising method for tumor treatment.

Denitrification is the stepwise microbial reduction of nitrate or nitrite (NO2−) to nitrogen gas via the obligate intermediates nitric oxide (NO) and nitrous oxide (N2O). Substantial N2O accumulation has been reported in denitrifying enhanced biological phosphorus removal (EBPR) bioreactors enriched in denitrifying polyphosphate accumulating organisms (DPAOs), but little is known about underlying mechanisms for N2O generation, prevalence of complete versus truncated denitrification pathways, or the impact of NO2− feed on DPAO-enriched consortia. To address this knowledge gap, we employed genome-resolved metagenomics to investigate nitrogen transformation potential in a NO2− fed denitrifying EBPR bioreactor enriched in Candidatus Accumulibacter and prone to N2O accumulation. Our analysis yielded 41 near-complete metagenome-assembled genomes (MAGs), including two co-occurring Accumulibacter strains affiliated with clades IA and IC (the first published genome from this clade) and 39 non-PAO flanking bacterial genomes. The dominant Accumulibacter clade IA encoded genes for complete denitrification, while the lower abundance Accumulibacter clade IC harbored all denitrification genes except for a canonical respiratory NO reductase. Analysis of the 39 non-PAO MAGs revealed a high prevalence of taxa harboring an incomplete denitrification pathway. Of the 27 MAGs harboring capacity for at least one step in the denitrification pathway, 10 were putative N2O producers lacking N2O reductase, 16 were putative N2O reducers that lacked at least one upstream denitrification gene, and only one harbored a complete denitrification pathway. We also documented increasing abundance over the course of reactor operation of putative N2O producers. Our results suggest that the unusually high levels of N2O production observed in this Accumulibacter-enriched consortium are linked in part to the selection for non-PAO flanking microorganisms with truncated denitrification pathways.

With the improvement of nanotechnology and nanomaterials, redox-responsive delivery systems have been studied extensively in some critical areas, especially in the field of biomedicine. The system constructed by redox-responsive delivery can be much stable when in circulation. In addition, redox-responsive vectors can respond to the high intracellular level of glutathione and release the loaded cargoes rapidly, only if they reach the site of tumor tissue or targeted cells. Moreover, redox-responsive delivery systems are often applied to significantly improve drug concentrations in targeted cells, increase the therapeutic efficiency and reduce side effects or toxicity of primary drugs. In this review, we focused on the structures and types of current redox-responsive delivery systems and provided a comprehensive overview of relevant researches, in which the disulfide bond containing delivery systems are of the utmost discussion.

A perpendicularly magnetized synthetic antiferromagnetic structure is a promising alternative to a single ferromagnetic layer in spintronic applications because of its low net magnetization and high thermal stability. In this work, the ferromagnetic layers in the synthetic antiferromagnetic structure are simplified to 'soft' Co70Fe30 layers with the aid of ultrathin Pt insert layers between the ferromagnetic layers and the exchange coupling Ru layer to lower the energy consumption. In the current-driven manipulation of the magnetization, asymmetric switching loops are observed, which originate from the edge domain walls induced by the growth of the electrode pads. The edge domain walls preserved beneath the electrode pad help the switching process skipping the nucleation stage, lowering the critical current density to the order of 106 A cm-2. The present work broadens the choice of ferromagnetic layers for building an SAF structure and highlights a new way to utilize the synthetic antiferromagnetic structure as a building block in low-energy-consuming spintronic devices.

Modern therapeutic cancer vaccines need simple and effective formulations to enhance both humoral and cellular immune responses. Nanoparticles have obtained more and more attention in the development of vaccine delivery platforms. Moreover, nanoparticles-based vaccine delivery platform has high potential for improving the immunogenicity of vaccine. The Food and Drug Administration (FDA) has approved many types of iron oxide nanoparticles for clinical use, such as treating iron deficiency, contrast agents for magnetic resonance imaging (MRI) and drug delivery platforms. In this study, we explored a novel combined use of iron oxide nanoparticles (superparamagnetic Fe3O4 nanoparticles) as a vaccine delivery platform and immune potentiator, and investigated how this formulation affected cytokine expression in macrophages and dendritic cells (DCs) in vitro and tumor growth in vivo. Comparing with soluble OVA alone and iron oxide nanoparticles alone, we found significant differences in immune responses and tumor inhibition induced by OVA formulated with iron oxide nanoparticles. Our iron oxide nanoparticles greatly promoted the activation of immune cells and cytokine production, inducing potent humoral and cellular immune responses. These results suggest that this nanoparticle-based delivery system has strong potential to be utilized as a general platform for cancer vaccines.

Manipulating a quantum state via electrostatic gating has been of great importance for many model systems in nanoelectronics. Until now, however, controlling the electron spins or, more specifically, the magnetism of a system by electric-field tuning has proven challenging1–4. Recently, atomically thin magnetic semiconductors have attracted significant attention due to their emerging new physical phenomena5–13. However, many issues are yet to be resolved to convincingly demonstrate gate-controllable magnetism in these two-dimensional materials. Here, we show that, via electrostatic gating, a strong field effect can be observed in devices based on few-layered ferromagnetic semiconducting Cr2Ge2Te6. At different gate doping, micro-area Kerr measurements in the studied devices demonstrate bipolar tunable magnetization loops below the Curie temperature, which is tentatively attributed to the moment rebalance in the spin-polarized band structure. Our findings of electric-field-controlled magnetism in van der Waals magnets show possibilities for potential applications in new-generation magnetic memory storage, sensors and spintronics. Few-layer semiconducting Cr2Ge2Te6 shows bipolar gate-tuned magnetism below its ferromagnetic Curie temperature.

Peripheral nerve defect is a common and severe kind of injury in traumatic accidents. Melatonin can improve peripheral nerve recovery by inhibiting oxidative stress and inflammation after traumatic insults. In addition, it triggers autophagy pathways to increase regenerated nerve proliferation and to reduce apoptosis. In this study, we fabricated a melatonin-controlled-release scaffold to cure long-range nerve defects for the first time. 3D manufacture of melatonin/polycaprolactone nerve guide conduit increased Schwann cell proliferation and neural expression in vitro and promoted functional, electrophysiological and morphological nerve regeneration in vivo. Melatonin nerve guide conduit ameliorated immune milieu by reducing oxidative stress, inflammation and mitochondrial dysfunction. In addition, it activated autophagy to restore ideal microenvironment, to provide energy for nerves and to reduce nerve cell apoptosis, thus facilitating nerve debris clearance and neural proliferation. This innovative scaffold will have huge significance in the nerve engineering.

Treating peripheral nerve injury faces major challenges and may benefit from bioactive scaffolds due to the limited autograft resources. Graphene oxide (GO) has emerged as a promising nanomaterial with excellent physical and chemical properties. GO has functional groups that confer biocompatibility that is better than that of graphene. Here, GO/polycaprolactone (PCL) nanoscaffolds are fabricated using an integration molding method. The nanoscaffolds exhibit many merits, including even GO nanoparticle distribution, macroporous structure, and strong mechanical support. Additionally, the process enables excellent quality control. In vitro studies confirm the advantages of the GO/PCL nanoscaffolds in terms of Schwann cell proliferation, viability, and attachment, as well as neural characteristics maintenance. This is the first study to evaluate the in vivo performance of GO‐based nanoscaffolds in this context. GO release and PCL biodegradation is analyzed after long‐term in vivo study. It is also found that the GO/PCL nerve guidance conduit could successfully repair a 15 mm sciatic nerve defect. The pro‐angiogenic characteristic of GO is evaluated in vivo using immunohistochemistry. In addition, the AKT‐endothelial nitric oxide synthase (eNOS)‐vascular endothelial growth factor (VEGF) signaling pathway might play a major role in the angiogenic process. These findings demonstrate that the GO/PCL nanoscaffold efficiently promotes functional and morphological recovery in peripheral nerve regeneration, indicating its promise for tissue engineering applications.

In this work, Zn particles with magnetic shell were synthesised and investigated. Zn particles with different sizes were synthesised by arc-discharge method, and then the Zn particles were put in a suitable concentration of FeSO4 solution with a surface active agent. After some time, the Zn particles with magnetic shell were produced. The particles contain oxygen shell probably in the form of FeO and ZnO, while the core material is Zn. From the saturation magnetisation at room temperature and transmission electron microscopy (TEM) images, it is noticed that the FeO was first formed on the surface of Zn and then ZnO appeared with increasing reaction time. The microwave absorption is not as good as that reported in other materials, because of the weak magnetisation and the faulty core–shell structure formed by metal core and magnetic shell.

Polycationic vectors are used widely in the field of gene delivery, while currently their immune activities in vivo are poorly understood. In this comprehensive review, we aim to present an overview of existing mechanisms of adverse immune responses induced by the polycation/gene complexes, which includes the polycations themselves, the gene sequences and the ROS produced by them. These causes can induce pro-inflammatory cytokines, hypersensitivity as well as the activation of toll-like receptors, and finally the immunostimulation occur. In addition, we introduce some different opinions and research results on the immunogenicity of classical polycations such as polylysine (PLL), polyethyleneimine (PEI), polyamidoamine dendrimers (PAMAM), chitosan and gelatin, most of which have immunogenicity and can induce immunoreactions in vivo. The methods now used to adjust their immunogenicity are shown in the final part of this review. Nowadays, there is still no accurate conclusion on immunogenicity of polycations, which confuses researchers seriously in in vivo test. We conclude that further research is needed in order to skillfully utilize or inhibit the immunogenicity of these polycationic vectors.

We report on a field induced domain evolutionary procedure in the anisotropic Nd-Dy-Fe-Co-B/MgO/Fe multilayers by using first-order-reversal-curves and magnetic force microscopy. Different reversal behaviors and domain sizes are found in well coupled and decoupled multilayers by changing the thickness of the spacer layer. The competition between dipolar magnetostatic energy and Zeeman energy is evaluated by in-field observation throughout nucleation and annihilation processes. In addition, lithography-patterned arrays of soft Fe disks onto a continuous Nd-Dy-Fe-Co-B hard-magnetic layer are designed. By decreasing the applied field, it is found that magnetization orientations of the Fe disk and Nd-Dy-Fe-Co-B layer are aligned parallel. In the decoupled disk, although the out-of-plane magnetization orientations are observed, the orientation of the domains in the Fe disk is random. Furthermore, it is found that a stronger anisotropy of the Nd-Dy-Fe-Co-B layer decreases the interaction length. Our results provide a new understanding of anisotropic nanocomposite magnets with long-ranged magnetic interactions.

Scientists have been attracted by polymersomes as versatile drug delivery systems since the last two decades. Polymersomes have the potential to be versatile drug delivery systems because of their tunable membrane formulations, stabilities in vivo, various physicochemical properties, controlled release mechanisms, targeting abilities, and capacities to encapsulate a wide range of drugs and other molecules. Asymmetrical polymersomes are nano- to micro-sized polymeric capsules with asymmetrical membranes, which means, they have different outer and inner coronas so that they can exhibit better endocytosis rate and endosomal escape ability than other polymeric systems with symmetrical membranes. Hence, asymmetrical polymersomes are highly promising as self-assembled nano-delivery systems in the future for in vivo therapeutics delivery and diagnostic imaging applications. In this review, we prepared a summary about recent research progresses of asymmetrical polymersomes in the following aspects: synthesis, preparation, applications in drug delivery and others.

microRNAs (miRNAs) are short non-coding RNAs that regulate gene expression by base pairing with their target messenger RNAs. Dysregulation of miRNAs is involved in the pathological initiation and progression of many human diseases. miR-221 and miR-222 (miR-221/222) are two highly homologous miRNAs, and they are significantly overexpressed in several types of human diseases. Silencing miR-221/222 could represent a promising approach for therapeutic studies. In the present review, we will describe the potential value of miR-221/222 as diagnostic, prognostic, and therapeutic biomarkers in various diseases including cancer and inflammatory diseases.

Understanding the magnetic interactions and magnetization reversal behaviors in composite magnets is helpful for exerting the optimum magnetic properties. In this work, we found that the squareness of the hysteresis loop is weakened by increasing the thickness of Ta space-layer in La-Nd-Fe-B/Ta/Co multilayers, but improved by designing the Co layer as periodic arrays of disks. Magnetization reversal behaviors were studied using first order reversal curves (FORC) and magnetic force microscopy (MFM). It has been found that the nucleation and propagation of new domains mainly lead to the irreversible magnetization process. By patterning the Co layer as periodic arrays of disks, the dipolar interaction is enhanced due to the shape-dependent anisotropy of Co disks, leading to better squareness. Our results benefit to understand the magnetic interactions and magnetization reversal behaviors in La-Nd-Fe-B/Co composite systems.

We investigate the spin–orbit torque (SOT) induced magnetization switching in the Pt/CoFe structure via inserting NiO or MgO interlayers. The effective spin Hall angles are enhanced by inserting a NiO layer and decreased by a MgO interlayer, through the harmonic Hall measurement. Both the MgO and NiO interlayers decrease the critical switching current and the minimum in-plane field required for completely switching, which is decreased down to about 50 Oe for a sample with MgO and 25 Oe for a sample with NiO. This originates from the reduction of the Dzyaloshinskii-Moriya interaction by inserting the oxide interlayers, which is confirmed by the Kerr images for the switching process. We confirm that the oxide interlayer is an efficient way to modify the SOT-induced magnetization switching and reveal the possibility of the SOT-induced switching for double MgO-based perpendicular magnetic tunneling junctions.

The effect of an ultrathin W interlayer on the perpendicular magnetic anisotropy (PMA), spin orbit torque (SOT), and SOT-induced magnetization switching of Ta/CoFeB/MgO films has been investigated. Both the anisotropy energy density and the spin-torque efficiency are enhanced by inserting the ultrathin W interlayer. The results suggest that the large enhancement of the spin-torque efficiency originates from the increase in the interfacial spin transparency using a simplified drift-diffusion model. The minimum in-plane field required for SOT-induced complete switching is reduced to 12 Oe for the sample with the W interlayer, which is confirmed by polar Kerr microscopy. The reversed domain nucleation and propagation of the reversal processes have been observed by Kerr imaging. It is concluded that the ultrathin W interlayer increases the spin transmission and reduces the strength of the Dzyaloshinskii–Moriya interaction. Our result suggests that the interface modification is an efficient way to modulate the PMA and SOT.

Small interfering RNA (siRNA) is an effective and specific method for silencing genes. However, an efficient and nontoxic carrier is needed to deliver the siRNA into the target cells. Tumor necrosis factor α (TNF-α) plays a central role in the occurrence and progression of rheumatoid arthritis. In this study, we pre-synthetized a degradable cationic polymer (PDAPEI) from 2,6-pyridinedicarboxaldehyde and low molecular weight polyethyleneimine (PEI, Mw=1.8 kDa) as a gene vector for the delivery of TNF-α shRNA. The PDAPEI/pDNA complex showed a suitable particle size and stable zeta potential for transfection. In vitro study of the PDAPEI/pDNA complex revealed a lower cytotoxicity and higher transfection efficiency when transfecting TNF-α shRNA to macrophages by significantly down-regulating the expression of TNF-α. Moreover, the complex was extremely efficient in decreasing the severity of arthritis in mice with collagen-induced arthritis (CIA). PDAPEI delivered TNF-α shRNA has great potential in the treatment of rheumatoid arthritis.

Spin-orbit torques (SOTs) and the perpendicular magnetic anisotropy (PMA) in Ta/W/CoFeB/MgO structures have been investigated by varying the thickness of the W layer. Addition of the W layer gives rise to enhancement of the annealing stability and perpendicular anisotropy field. After annealing at high temperature, a high-resistivity is obtained for samples with W layer (up to 2 nm thickness), which indicates the existence of β-W phase. A giant spin Hall angle of 0.50 is found in Ta/W/CoFeB/MgO structures with a 2 nm W layer by using the harmonic Hall voltage measurement. The lowest switching current density of 6 MA/cm2 is achieved in the sample with 1 nm W layer, indicating that a strong interfacial spin Hall effect may exist in the CoFeB/W interface. The study may provide a way to obtain simultaneously a large PMA as well as a high efficiency of SOTs.

In this article number https://doi.org/10.1002/advs.201700499, Yuanming Ouyang, Weien Yuan, Cunyi Fan, and co‐workers present 3D integration molding of a graphene oxide/polycaprolactone nanoscaffold. The nanoscaffold has high electrical conductivity, has excellent biocompatibility with multiple pores for free exchange of nutrients and water, and can support long‐term nerve regeneration in vivo after traumatic injury. This innovative complex is vital to functional neurite sprouting and angiogenic restoration in nerve tissue engineering.

The electric power steering (EPS) system is designed to reduce the effort exerted by driver on the steering wheel. One of the most common and critical failures of EPS is the soft-disability of the torque sensor or the loss of its signal, which leads to the instant shutdown of the EPS system while turning and causes serious traffic accidents. In this paper, a novel controller based on the self-alignment torque (SAT) estimation was designed to remedy the soft-disability of EPS system. After the SAT estimation method was verified by the empirical Magic Formula (MF) tire model, the remedy control strategy based on the SAT estimation was developed and evaluated by simulations under step and sinusoidal inputs. To further evaluate the performance of the controller on a real vehicle, experiments on a real EPS system were implemented under step and sinusoidal inputs. The results of simulation and experiment using the controller based on estimated SAT showed this controller to be feasible and capable of eliminating the abrupt reaction torque increment caused by shutdown of EPS and of remedying the soft-disability of EPS system under common input signals.

Torque ripple in an electric power steering (EPS) system can be induced by the phase lag between steer angle and rack displacement, non-linear friction, and disturbances from road and sensor noise, especially during high-frequency manoeuvres. This paper investigates the application of robust and non-linear sliding mode control (SMC) strategies to an EPS system, based on a reference model to reduce the torque ripple and stabilize the dynamics of the EPS system. The dynamics of the EPS system is described by a non-linear state-space model with realistic non-linear friction and disturbances from road and sensor noise. Meanwhile, the ideal EPS system, in which the rack displacement tracks the steer angle perfectly, is proposed as the reference model. A non-linear sliding mode observer (SMO) is also developed to estimate the unmeasurable states. The performance and robustness of SMC and SMO are demonstrated using various simulations and compared with traditional alternatives. The results of these simulations reveal that the non-linear SMC and SMO strategies can reduce the torque ripple to achieve a better steering feel and more stable driving, and can be applied to commercial EPS systems.

In chalcogenide topological insulator materials, two types of magnetoresistance (MR) effects are widely discussed: a sharp MR dip around zero magnetic field, associated with the weak antilocalization (WAL) effect, and a linear MR (LMR) effect that generally persists to high fields and high temperatures. We have studied the MR of thin films of the topological insulator Bi2Te3 from the metallic to semiconducting transport regime. In the metallic samples, the WAL is difficult to identify owing to the low magnitude of the WAL compared to the samples’ conductivity. Furthermore, the sharp WAL dip in the MR is clearly present in samples with a higher resistivity. To correctly account for the low-field MR with the quantitative theory of the WAL according to the Hikami–Larkin–Nagaoka (HLN) model, we find that the classical (linear) MR effect should be taken into account in combination with the WAL quantum correction. Otherwise, the WAL fitting alone yields an unrealistically large coefficient α in the HLN analysis. This work clarifies the WAL and LMR as two distinct effects and offers an explanation for the overly large α in the WAL analysis of topological insulators in some studies.

We report on the magneto-transport properties of chemical vapor deposition grown films of interconnected Bi2Te3 nanoplates. Similar to many other topological insulator (TI) materials, these granular Bi2Te3 films exhibit a linear magneto-resistance (LMR) effect which has received much recent attention. Studying samples with different degree of granularity, we find a universal correlation between the magnitude of the LMR and the average mobility () of the films over nearly two orders of magnitude change of . The granularity controlled LMR effect here is attributed to the mobility fluctuation induced classical LMR according to the Parish-Littlewood theory. These findings have implications to both the fundamental understanding and magneto-resistive device applications of TI and small bandgap semiconductor materials.

Control of the nucleation and growth rate by H 2 O 2 and NaOH provides a facile route to harvest nickel nanoflowers. The choice of NaOH and ethylene glycol (EG) plays the important role in the formation of Ni nanoflowers; while the addition of H 2 O 2 is another key role for the preparation of uniform Ni nanoflowers. HRTEM and SEAD patterns show that the Ni nanoflowers are single-crystal and grow along the [200] direction. The magnetic measurement demonstrated that the Ni nanoflowers presented ferromagnetic properties. Furthermore, Ni nanoflowers show potential utilization for the removal of dyes in a wastewater treatment process.

Magnetic vortices in patterned nanocomposite structures have been studied. A double-vortex structure consisting of two vortex cores with opposite chiralities and two edge half-vortices is realized in a micron-size circular disk, which consists of [Co/Pd]7/Ru/Py. A systemic study of the magnetization reversal of a double-vortex state and a single vortex state in an out-of-plane applied field has been performed by means of magnetic force microscopy. It is found that the interlayer exchange and dipolar interactions are critical for nucleation and annihilation of the double-vortex and the single vortex states. Micromagnetic simulations prove that the double-vortex state can stably exist in a patterned nanocomposite structure. Magnetic configurations ranging from the double-vortex and single vortex states to other multidomain states and the in-plane single-domain state are observed. The dependence of the magnetic configuration on the thickness of the soft-magnetic layer and spacer layer is presented in an expe...

The magnetic properties and the possible interaction mechanisms of anisotropic soft- and hard-magnetic multilayers have been investigated by altering the thickness of different kinds of spacer layers. The metal Ta and the insulating oxides MgO, Cr2O3 have been chosen as spacer layers to investigate the characteristics of the interactions between soft- and hard-magnetic layers in the anisotropic Nd-Dy-Fe-Co-B/α-Fe multilayer system. The dipolar and exchange interaction between hard and soft phases are evaluated with the help of the first order reversal curve method. The onset of the nucleation field and the magnetization reversal by domain wall movement are also evident from the first-order-reversal-curve measurements. Reversible/irreversible distributions reveal the natures of the soft- and hard-magnetic components. Incoherent switching fields are observed and the calculations show the semiquantitative contributions of hard and soft components to the system. An antiferromagnetic spacer layer will weaken t...

The well-known detail-preserving anisotropic diffusion (DPAD) for smoothing speckle noise in synthetic aperture radar (SAR) images suffers from poor despeckling performance near edges and serious blocking artefacts in homogeneous regions. The DPAD is extended to effectively alleviate the aforementioned problems by embedding the mean curvature motion controlled by an adaptive coupling function into the DPAD's diffusion equation.

The purpose of this study is to compare the characteristics of psychophysical tests between cochlear implant children with large vestibular aqueduct syndrome and normal inner ear and to analyse the characteristics of psychophysical and impedance tests for cochlear implant patients with large vestibular aqueduct syndrome.One hundred and thirty-one cochlear implant pre-lingual deafness patients participated in this study. They received cochlear implant surgery at the age of 1.5 to 12 years old from Nov, 1998 to Aug, 2003. The patients were divided into two groups. Group A had 111 patients with normal inner ear. Group B had 20 patients with radiographically proven large vestibular aqueduct syndrome. All of the patients were inserted with Nucleus 24M. The time of the first programming session was approximately 4 weeks after surgery. The psychophysical tests included T and C-Level tests. The programming techniques used in the test were suitable for the age of the patients. The R116 and R126 software were used to test the impedance of the electrodes automatically.Using the independent-samples t-test, the impedance and T/C-Level of each electrode did not differ significantly between group A and B ( P0.05). The impedance and T/C-Level were not significantly different between group A and B at the time of switch-on, 1 week, 2 weeks, 3 weeks, 2 months, 3 months, 6 months, 9 months and 1 year after switch-on (P0.05).The parameters of mapping were not significantly different between cochlear implant children with large vestibular aqueduct syndrome and normal inner ear. The management and procedure of mapping used in cochlear implant children with normal inner ear can be used in the children with large vestibular aqueduct syndrome.

To explore the different surgical choices for treating osteomas of the sinuses. To summarize the management and characteristics of each surgical operation.A retrospective evaluation of thirty-one patients with osteomas of the sinuses from June 1993 to December 2001 was presented. Fourteen patients were operated through a lateral rhinotomy with radical operation in 13 cases. Eight patients were operated by nasal endoscopic management, osteomas were completely removed. Eight osteomas were removed with a coronal incision. One case underwent Caldwell-Luc surgery. The clinical symptoms, location of osteomas, and surgical procedures were analyzed.The complications of brain spinal fistula occurred in 2 cases, but they were treated in the same time of operations. One patient had a single blindness after the operation. Twenty-eight cases were followed-up for 1 to 9 years with an average of three point seven years. Twenty-six patients had no recurrence, two cases lived with the remains of osteomas.The choice of surgical operations on osteomas of the sinuses was mainly decided by the location and size of osteomas, and the anatomic characteristics of sinuses, in the meanwhile, the organ function, the cosmetology, and the doctors experience were taken into account.

The aim of the study is to determine parameters that be predictive of function of facial nerve after facial nerve decompression surgery.Fifteen New Zealand white rabbits (30 facial nerves) and 21 patients with peripheral facial paralysis were monitored intraoperatively during facial nerve decompression surgery. These patients were followed up for at least 6 months.Threshold of EMG is a steady parameter of assessing the function of facial nerve. The threshold between different segments of facial nerve has no difference in New Zealand white rabbits. That there exist EMG events were correlated significantly with good postoperative facial nerve function.Threshold of EMG can be used as objective and steady parameter that assess the function of facial nerve. Intraoperative monitoring events can be used for assessment of postoperative facial nerve function.

The aim of this research is to analyse and compare the psychophysical tests in different age of patients with a cochlear implant.One hundred and seventy patients with Nucleus CI24M cochlear implant system participated in this study. The patients were divided into four groups according to their age. They were group A (3 year), B(3-6 year) C(6-12 year) and D(12 year). The psychophysical tests included T and C-Level evaluation.C-Levels of each electrode (except electrode No. 20) were significantly different between group A and D at the time of one month after switch-on (P0.01, P0.05 for the No. 2, 18, 19, 21, 22 electrode). The normalized differences between used C-Levels and C-Levels for group D were significantly higher than the other three groups at the switch-on session (P0.01, P0.05 between group D and C). The normalized differences between used C-Levels and C-Levels were significantly different for the group A and D at one week after first programming session (P0.05).T and C-Level for different age groups were different. The normalized differences between used C-Levels and C-Levels were significantly different among the four groups in the few weeks after switch-on.