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Crystal structure, morphology, magnetic, and dielectric properties of (1 − x)Bi2Fe4O9–xMgFe2O4 bicomponent ceramics are investigated in detail. The material has been synthesized via sol–gel method. Analysis of X-ray diffraction data of the bicomponent ceramics shows the coexistence of orthorhombic Bi2Fe4O9 and spinel MgFe2O4 phases with no third phase. Microstructural and surface morphology displays the homogeneous grain distribution with different grain sizes of Bi2Fe4O9 and MgFe2O4. The magnetic measurement shows decreasing coercivity and increasing values of remnant and saturation magnetization with the increase in MgFe2O4. Temperature-dependent dielectric properties and electrical modulus are conducted in the temperature range of 27–527 °C with the frequency ranging from 1 to 30 kHz. Two abnormal peaks are, respectively, observed at low and high temperature ranges. The variation of electric properties is closely related to the composition of MgFe2O4. The results of dielectric and electrical modulus indicate the appearance of dielectric relaxation in (1 − x)Bi2Fe4O9–xMgFe2O4. Combined with the study of activation energy, the dielectric relaxation is mainly induced by different electric responses of various charge carriers intrinsically dominating in a thermally activated process with the incorporation of MgFe2O4. The combination of Bi2Fe4O9 and MgFe2O4 enhances the coexistence of magnetic and electric properties in the present composites. It is quite promising from application point of view.

随着医学技术的发展，新的检查方法及设备层出不穷，临床诊疗越来越依赖辅助检查，细致详尽的、充满人文关怀的病史询问及经典的视、触、叩、听则有被边缘化的趋势。临床诊疗中，合理与适宜的检查是必需的，但“好的病史是临床检查的基础”，选择有针对性的辅助检查并解读其报告，应建立在详尽准确的病史基础之上。仅通过全面而有技巧的问诊，可以区分90%以上的症状是眩晕或是非旋转性头晕，可以基本明确70%~80%头晕/眩晕患者的病因，但头晕/眩晕病史采集并非易事，其涵盖疾病和内容非常广泛，需花费很长时间。如何在有限时间内有所侧重，在繁忙的临床工作中更高效地采集到更准确的信息？本文从头晕/眩晕诊疗思路入手，介绍面对不同患者的问诊策略。.

Different symmetry breaking ways determine various magnetization switching modes driven by spin–orbit torques (SOT). For instance, an applied or effective field parallel to applied current is indispensable to switch magnetization with perpendicular anisotropy by SOT. Besides of this mode, here we experimentally demonstrate a distinct field-free switching mode in a T-type magnetic system with structure of MgO/CoFeB/Ta/CoFeB/MgO where a perpendicular layer with tilted easy axis was coupled to an in-plane layer with a uniaxial easy axis. Current was applied orthogonal to both easy axes and thus also normal to an in-plane effective field experienced by the perpendicular layer. Dynamic calculation shows perpendicular layer could be switched at the same time as the in-plane layer is switched. These field-free switching modes realized in the same T-type magnetic system might expedite the birth of multi-state spin memories or spin logic devices which could be operated by all electric manners. Spin-orbit torque (SOT) induced magnetization switching facilitates all electric multi-state spin memories and spin logic devices. Here the authors show a new SOT field-free switching mode where the perpendicular layer with tilted easy axis is coupled to an in-plane layer with a uniaxial easy axis.

老年性聋是指随着年龄的增加逐渐发生的以高频听力下降为主的感音神经性听力损失，其发病原因及机制复杂，目前缺乏有效的临床治疗手段。本文从发病机制，病理分型，诊断标准及干预措施等方面做一系统综述。.

听觉系统疾病是人类最常见的感觉系统障碍。由于哺乳动物耳蜗毛细胞的不可再生性，其损伤是听力丧失的主要原因。在感音神经性聋的预防及治疗中，维持毛细胞及内耳中其他类型细胞的正常功能是治疗过程中至关重要的环节。自噬是细胞的一种重要的、高度保守的自我调控机制，在正常的生理过程中起"管家"的作用，如清除聚集和错误折叠的蛋白质或受损的细胞器。在应激状态下，自噬则具有维持细胞功能和促存活的作用。本文主要介绍近期关于内耳在不同损伤条件下，如遗传性聋、药物性聋、衰老和噪声暴露所致感音神经性聋中自噬的调控机制及研究进展，阐明自噬有望成为治疗听觉系统疾病新的切入点。.

Establishing a stable resin-dentin hybrid layer is an effective method to improve the adhesion durability of the restoration. The biomodification of dentin by cross-linkers can enhance the mechanical properties of collagen and resistance to enzymatic hydrolysis while, inhibiting the process of demineralization and promoting the remineralization of dentin, which has the potential clinical applicability of preventing dental caries and improving adhesive property. This review summarizes the biomodification of dentin type Ⅰ collagen by different cross-linkers.建立稳定的树脂-牙本质混合层是提高修复体粘接耐久性的有效方法。交联剂对牙本质的生物改性可增强胶原的力学性能及抗酶解性，抑制脱矿进程并促进牙本质再矿化，具有预防龋齿以及改善粘接剂性能的临床价值。本文分类阐述不同交联剂对牙本质Ⅰ型胶原的生物改性作用。.

Confronting with the gigantic volume of data produced every day, raising integration density by reducing the size of devices becomes harder and harder to meet the ever-increasing demand for high-performance computers. One feasible path is to actualize more logic functions in one cell. In this respect, we experimentally demonstrate a prototype spin-orbit torque based spin logic cell integrated with five frequently used logic functions (AND, OR, NOT, NAND and NOR). The cell can be easily programmed and reprogrammed to perform desired function. Furthermore, the information stored in cells is symmetry-protected, making it possible to expand into logic gate array where the cell can be manipulated one by one without changing the information of other undesired cells. This work provides a prospective example of multi-functional spin logic cell with reprogrammability and nonvolatility, which will advance the application of spin logic devices.

We report on the influence of the annealing temperature on the crystal structure phase change, effective anisotropy energy and magnetization reversal of electrodeposited Fe3Ga nanowires (NWs) with diameter of 80 nm. Scanning transmission electron microscopy (STEM) energy-dispersive X-ray (EDX) spectroscopy technique for the elemental mapping of Fe3Ga NWs showed clearly the homogeneous distribution of Fe and Ga. These NWs are highly aligned to each other and exhibits high geometrical aspect ratio. The crystal structure of these nanowires shows strong dependence on the sintering temperature. X-ray diffraction reflects the highly textured A2-disorderd phase with precipitates of DO3 and L12 phase for as-synthesized Fe3Ga NWs. As the annealing temperature increases, the intensity of strong disordered phase A2 or short range order phase DO3 suddenly decreases and grains are textured along the stable L12 phase with small precipitates of DO3 phase. As a result of these structural changes, magnetization reversal mode switches from transverse to a combination of transverse and vortex modes. Angular magnetic response at room temperature is employed to identify the magnetization reversal modes for Fe3Ga NWs. Temperature dependent coercivity response can be understood in terms of thermal activation over an energy barrier with a 3 2 – power dependence on the field.

Besides spin-transfer torque, spin–orbit torque (SOT) provides us with another electrical way for developing magnetic random access memory (MRAM) based on magnetic tunnel junctions (MTJs). By using a CoFeB/Ta/CoFeB T-type magnetic structure as a synthetic free layer, we have realized a magnetic-field-free MTJ switchable by SOT. In the T-type structure, an in-plane CoFeB layer is coupled to a perpendicular CoFeB layer via a Ta spacer. The spacer layer not only mediates exchange coupling but also generates strong SOT, which drives sharp switching between the low and high resistance states of the MTJ without any applied magnetic fields. This work could provide an efficient way toward realization of field-free SOT-MRAM or logic devices.

We report the tunneling anisotropic magnetoresistance (TAMR) in fully epitaxial Fe/Barrier/Fe (001) magnetic tunnel junctions (MTJs) where the Barrier is annealed MgO, MgAlOx, MgO-MgAlOx, or as-grown MgO/MgAlOx. The TAMR was measured as the magnetization of Fe electrodes rotated from in-plane to out-of-plane. The angular dependence of TAMR for all samples exhibited superposed behavior of twofold and fourfold symmetries. The proportion of fourfold symmetry is larger in MTJs with MgO and MgO-MgAlOx than that in MTJs with MgAlOx and MgO/MgAlOx barriers. By characterizing inelastic electron tunneling spectroscopy in the antiparallel state and parallel conductance of the MTJs, we revealed diverse minority interfacial resonant states (IRSs) and different contributions from Δ1 and Δ5 symmetry states to the conductance in the MTJs. Our results illustrate that the minority IRS dominated by Δ5 symmetry can mix with majority Δ1 states and give rise to the enhanced fourfold symmetric angular dependence in MTJs with MgO and MgO-MgAlOx barriers.

We report the Hanle magnetoresistance (HMR) due to the spin precession of edge spin accumulation and interfacial spin current. Because of spin-orbit coupling (SOC), an electric current is accompanied by a transverse spin current, which builds up the spin accumulation at surfaces of Pt and the spin current across the YIG/Pt interface. Once a magnetic field is applied, the precession of spins will decrease the edge spin accumulation and interfacial spin current, which leads to an increased resistance of Pt via ISHE. Spin relaxation governs the HMR from edge spin accumulation, while spin diffusion and spin conversion play important roles in the HMR from interfacial spin current. This work provides another method to investigate the spin-orbit coupling by electrical measurement.

Obstructive sleep apneahypopnea syndrome(OSAHS) is a kind of disease with a complex etiology, a high incidence and a wide variety of therapeutic methods. as a firstline treatment of OSAHS, noninvasive continuous positive airway pressure(CPAP) encounters the problem of low compliance of theray.And other methods of treatment are all required to meet the strict of indications to obtain the effect of therapy. The large individual anatomical differences and the great variability of non anatomical factors of the upper airway stucture of OSAHS patients, determine the diversity of OSAHS treatment. The personalized therapy is an inevitable trend in the future. in this paper, the pathogenesis, treatment methods, treatment status and personalized diagnosis and treatment trends are summarized and discussed briefly in this paper.

Flexible control of magnetization switching by electrical manners is crucial for applications of spin-orbitronics. Besides of a switching current that is parallel to an applied field, a bias current that is normal to the switching current is introduced to tune the magnitude of effective damping-like and field-like torques and further to electrically control magnetization switching. Symmetrical and asymmetrical control over the critical switching current by the bias current with opposite polarities is both realized in Pt/Co/MgO and $\alpha$-Ta/CoFeB/MgO systems, respectively. This research not only identifies the influences of field-like and damping-like torques on switching process but also demonstrates an electrical method to control it., Comment: 8 pages, 6 figures

Spin manipulation in magnetic materials based on spin-orbit torque gives rise to promising families of magnetic memory and logic devices. In the synthetic antiferromagnetic structure of CoFeB/Ta/CoFeB where both CoFeB layers exhibit perpendicular anisotropy, we study the magnetization switching process based on the mechanism of spin-orbit torque and interlayer exchange coupling mediated by a Ta layer. The magnetization switching trigged by in-plane current is achieved. Though the heavy metal Ta layer is ultrathin, the critical current density is 8 × 106–1 × 107 A/cm2 with a bias field of 5–10 mT. Meanwhile, the current induced anti-damping-like field and field-like field are determined by the harmonic lock-in technique. Harmonic results suggest that the generation efficiency of the field-like field is ∼1.24 times that of the anti-damping-like field. The effective spin Hall angle of a Ta layer is derived to be around −0.158. Finally, we examine the magnetic properties of CoFeB layers as a function of temperature which indicates that the magnetic properties of bottom and top CoFeB layers have a close correlation with the interface quality and growth order.

Spin-orbit torque (SOT)-induced magnetization switching exhibits chirality (clockwise or counterclockwise), which offers the prospect of programmable spin-logic devices integrating nonvolatile spintronic memory cells with logic functions. Chirality is usually fixed by an applied or effective magnetic field in reported studies. Herein, utilizing an in-plane magnetic layer that is also switchable by SOT, the chirality of a perpendicular magnetic layer that is exchange-coupled with the in-plane layer can be reversed in a purely electrical way. In a single Hall bar device designed from this multilayer structure, three logic gates including AND, NAND, and NOT are reconfigured, which opens a gateway toward practical programmable spin-logic devices.

A polarization-mediated heterointerface is designed to research the thermal stability of magnetic metal/oxide interfaces. Using polarization engineering, the thermal stability of the interface between BiFeO3 and CoFeB can be improved by about 100°C. This finding provides new insight into the chemistry of the metal/oxide heterointerface.

We employed {\it in-situ} pulsed laser deposition (PLD) and angle-resolved photoemission spectroscopy (ARPES) to investigate the mechanism of the metal-insulator transition (MIT) in NdNiO$_3$ (NNO) thin films, grown on NdGaO$_3$(110) and LaAlO$_3$(100) substrates. In the metallic phase, we observe three dimensional hole and electron Fermi surface (FS) pockets formed from strongly renormalized bands with well-defined quasiparticles. Upon cooling across the MIT in NNO/NGO sample, the quasiparticles lose coherence via a spectral weight transfer from near the Fermi level to localized states forming at higher binding energies. In the case of NNO/LAO, the bands are apparently shifted upward with an additional holelike pocket forming at the corner of the Brillouin zone. We find that the renormalization effects are strongly anisotropic and are stronger in NNO/NGO than NNO/LAO. Our study reveals that substrate-induced strain tunes the crystal field splitting, which changes the FS properties, nesting conditions, and spin-fluctuation strength, and thereby controls the MIT via the formation of an electronic order parameter with Q$_{AF}\sim$(1/4, 1/4, 1/4$\pm$$\delta$)., Comment: submitted

We have investigated the thermoelectric power (TEP) and the electrical conductance of single-walled carbon nanotube (SWNT) strands containing large numbers of aligned crystalline ropes. A linear temperature dependence of TEP and a power-law behaviour of conductance were observed at low temperatures. The TEP increases with temperature at a very large slope of similar to 1 mu V K(-2) below similar to 50K, peaks around 100-150 K depending on the treatment of high temperature annealing, then decreases with the further increase of temperature. The large slope at low temperatures is interpreted as a property of the Luttinger liquid in the presence of defects.

Electrical resistivity of grain boundaries (GBs) was determined in nanocrystalline (nc) Cu specimens prepared by magnetosputtering and subsequent annealing. Extrapolating the microstrain dependence of GB resistivity, we derived electrical resistivity of GBs in a fully-relaxed state in Cu, being 2.04 x 10(-16) Omegam(2). (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Spin logic devices, due to their programmability and nonvolatility, are deemed as an ideal building block for the next generation of electronics. Though several types of spin logic based on domain wall motion, spin-field-effect transistor and automata made of magnetic nanoparticles have been proposed, an architecture with scalability, energy efficiency and compatibility with current complementary metal-oxide-semiconductor technology is still in urgent demand. Here, it is experimentally demonstrated that the spin Hall effect in magnetic films with perpendicular anisotropy can be utilized to construct such a spin logic device. Five commonly used logic gates with nonvolatility in a single device are realized. This demonstration could pave the way towards application of spintronics in logic circuits as well as the memory industry in the near future and could even give birth to logic-in-memory computing architectures.

Underfloor heating is known for its comfort due to the low and favourable temperature gradient in the heated space above the large floor area available for heating. This paper addresses the idea of improving the existing underfloor heating system by using an encapsulated phase change material (PCM) that melts and solidifies at about 28 °C, placed in the concrete floor during construction. The objective is to minimize the fluctuation in the floor surface temperature and to have sufficient heat storage so that heating can be done during the off-peak electricity period only. Two concrete slabs (0.5 m × 0.5 m × 0.095 m) were constructed with a hot water pipe embedded in both of them to provide the required heating. Nodules having a diameter of 75 mm and containing CaCl26H2O were placed in one of the concrete slabs prior to its moulding. Unlike the plain concrete slab, the concrete-PCM slab showed a much lower surface temperature fluctuation and maintained an acceptable surface temperature during the whole day even though the heating process was done for only 8 h. A simple one-dimensional model was developed to simulate the underfloor heating system, so that it can be used to optimize its design. Comparison between the measured and predicted performance of the two slabs for 3 days showed a reasonable agreement.

All electrical manipulation of magnetization is crucial and of great important for spintronics devices for the sake of high speed, reliable operation, and low power consumption. Recently, widespread interests have been aroused to manipulate perpendicular magnetization of a ferromagnetic layer using spin-orbit torque (SOT) without field. We report that a commonly used antiferromagnetic material IrMn can be a promising candidate as a functional layer to realize field-free magnetization switching driven by SOT in which IrMn is employed to act as both the source of effective exchange bias field and SOT source. The critical switching current density within our study is Jc = 2.2 × 107 A/cm2, which is the same magnitude as similar materials such as PtMn. A series of measurements based on anomalous Hall effect was systematically implemented to determine the magnetization switching mechanism. This study offers a possible route for IrMn application in similar structures.

This study investigated the anti-fungal activity of coptisine on Candida albicans growth.The metabolic power-time curves of Candida albicans growth at 37 degrees C affected by coptisine were measured by microcalorimetry using an LKB-2277 Bioactivity Monitor with stop-flow mode. Then, the diameter of inhibitory zones in the agar layer was observed using agar cup method, and the minimal inhibitory concentration (MIC) of coptisine on Candida albicans growth was determined by serial dilution method. From the principal component analysis on nine quantitative parameters obtained from the power-time curves, we could easily evaluate the anti-fungal activity of coptisine by analysing the change of values of the main two parameters, growth rate constant k and maximum power output in the log phase P(m, log). The results showed that coptisine had strong anti-fungal activity: at a low concentration (45 microg ml(-1)) began to inhibit the growth of Candida albicans and at a high concentration (500 microg ml(-1)) completely inhibited Candida albicans growth. Coptisine gave big inhibitory zones with diameters between 11 and 43 mm within test range, and the MIC of it was 1000 microg ml(-1).Coptisine had strong anti-fungal activity on Candida albicans growth. The method of microcalorimetry applied for the assay of anti-fungal activity of coptisine was quantitative, sensitive and simple.This work will provide useful information for the development of chemical biology policy in the use of anti-microbials in food and drug production.

We applied hydrostatic pressure (up to 10 GPa) to single-walled carbon nanotube bundles at low temperature (down to 2 K) to measure their magnetoresistance (MR) in a field up to 12 T. We found a pressure-induced transition in MR from positive to negative in the high-field regime. The onset of the transition occurs at approximately 1.5 GPa, which correlates closely with the tube shape transitions. The characteristics of the high-pressure MR are consistent with a model of pressure-induced two-dimensional weak localization.

The present study was undertaken to investigate the influence of serotonin (5-HT) on cochlear microcirculation.2 microliters 0.5% 5-HT were applied to round window membrane in anaesthetized guinea pigs. The three parameters as blood flow (CBF), number of blood cell moving (CMBC) and blood velocity (Veloc) of cochlear microcirculation were measured with laser doppler flowmeter. The mean arterial pressure (MABP) was recorded simultaneously.5-HT induced a biphasic response of reduction in cochlear blood flow. In the first phase, cochlear microcirculation showed a transient abruptly reduction. The CBF, CMBC and Veloc reached to 86.8%, 90.2% and 96.3% of the baseline respectively. The second phase reduced slowly. The CBF and CMBC decreased to 89.7% and 89.6% by average throughout the experiment period respectively. The Veloc and MABP had no significant changes.5-HT could decrease the cochlear, blood flow and result in cochlear microcirculation dysfunction.

The energetics of small zigzag carbon nanotubes at high temperature regime (T = 2500 K) is investigated via k-space tight-binding molecular dynamics (TBMD) simulations. It is found that the n dangling atoms at the end of a zigzag tube with 5 < n < 12 can automatically transform into an (n - 1)-member ring at the top, accompanied by the release of a C, dimer and the formation of (n - 1) pentagons and a hexagon-pentagon pair involving up to five layers of atoms. For tubes larger than (11, 0) or smaller than (6, 0), it is found that energetically it is more favorable for the tube to remain open. (C) 2002 Elsevier Science B.V. All rights reserved.

Both the magnetoconductance and the nonlinear differential conductance of multiwall carbon nanotube ropes have been studied at low temperture. Suppression in the differential conductance was observed at low bias voltages and at low temperatures, indicating the formation of a Coulomb gap. The magnetoconductance was found to follow a scaling law at both high and low temperatures, but with different mechanisms. The analysis of the data provides a sign of a non-Fermi-liquid-like behavior through magnetotransport measurement.

We have investigated the field and the bias-voltage dependencies of the electrical conductance, as well as the temperature dependence of the thermoelectric power of multiwall carbon nanotubes. Consistent picture has been obtained which indicates that electron–electron strong correlation is a major rhythm at low temperatures.

Die efferente Innervation des Innenohres entspringt im oberen Olivenkomplex, wie erstmals von Rassmussen im Jahre 1942 beschrieben wurde. Nach Ursprung und Projektion unterscheidet man zwei verschiedene Systeme: ein mediales und ein laterales. Die medialen Efferenten bilden synaptische Kontakte zu den auseren Haarzellen, die lateralen Efferenten innervieren die inneren Haarzellen.

Dendritische Zellen bilden ein System von antigenprasentierenden Zellen, das im Korper weit verbreitet ist. Sie sind charakterisiert durch typische dendritische Zellfortsatze und durch die Expression von MHC-Klasse-II-Molekulen aus ihrer Zelloberflache. Sie kommen in 2 Formen vor: In nichtlymphoiden Organen, wie z.B. in der Haut, treten sie als unreife dendritische Zellen auf. Als solche besitzen sie die Fahigkeit der Antigenerkennung und -verarbeitung und der Migration uber die Blutzirkulation bzw. uber efferente Lymphgefase in Lymph-knoten. In lymphoiden Organen (Lymphknoten, Milz) finden sich reife dendritische Zellen, die antigenspezifische T-Lymphozyten finden und stimulieren konnen. Dendritische Zellen sind somit in hohem Mase befahigt, eine primare Immunantwort auszulosen.

Acetylcholin ist der wichtigste efferente Neurotransmitter im Vestibularapparat der Saugetiere.