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Spin pumping and related phenomena have been observed recently in heavy metals and topological insulators, where the spin-orbit coupling plays an essential role. We have developed a spin-pumping formalism that explicitly includes the spin-orbit coupling at interfaces and disorder in the layers. Spin pumping across an interface with spin-orbit coupling and the attendant backflow are treated on an equal footing. We resolve some long-standing issues on the conflicting conclusions about the spin-diffusion length for Pt, and the origin of spin-memory loss at interfaces with heavy metals. In addition, we predict some heretofore unanticipated spin-pumping phenomena.

The influence of elevated temperature on the stability of sandwich structures is investigated. A new analytical solution is proposed that enables the calculation of the critical wrinkling stress in sandwich beams subjected to load and elevated temperatures. The effect of a through thickness temperature gradient is accounted for by imposing different stiffnesses of the core for the different temperatures. The sandwich beam studied in the paper is loaded in a simply supported four-point bending configuration, where one of the face sheets is heated. The experimental approach utilises high-speed imaging where the strains are calculated from measured displacements obtained from digital image correlation (DIC). A shift of the failure mode from face sheet yielding to face sheet wrinkling is observed with increasing temperatures. The results from the new analytical method agree well with corresponding experimental results. Finite element analysis is also conducted, which shows excellent correspondence with the theory and the experimental data. The work clearly demonstrates that under certain conditions the load response of the sandwich beam can become nonlinear and unstable, and hence will fail well below face sheet yielding load because of the loss of stiffness of the core material.

The paper presents an experimentally based and numerically supported investigation of the collapse behaviour of polymer foam cored sandwich beams subjected to combined mechanical and thermal loading. Recent analytical and numerical modelling results available in the literature have ascertained that collapse may be due to loss of stability induced by nonlinear interactions between mechanical loads and thermally induced deformations, when accounting for the reduction of the polymer foam core mechanical properties with increasing temperature. In the paper, experiments are devised whereby a thermal gradient is introduced into a sandwich beam specimen loaded in three-point bending. The experiments cover a range of temperatures where one face sheet is heated from room temperature (25℃) to just below the glass transition temperature of the polymer foam core (70℃) and the other face sheet remains at room temperature. Digital image correlation (DIC) is used to obtain the local displacement field of the sandwich beam and its temperature is monitored using an infrared detector and thermocouples. The experimental results are compared with the predictions of both a generally nonlinear finite element model and an analytical so-called high-order sandwich panel theory (HSAPT) model. It is important to note that the HSAPT model has clear limitations as it takes into account only the geometric nonlinearity and thermal degradation of the foam core elastic properties, and it further assumes that the sandwich constituents are linear elastic with infinite straining capability. The HSAPT model predicts the occurrence of a strongly nonlinear load response leading to loss of stability (limit point behaviour). However, the experiments show that for the investigated sandwich beam configuration, it is necessary to include the nonlinear material properties in the modelling, as the nonlinear beam response leading to failure and collapse is significantly influenced by plastic deformations in the constituent materials. Thus, core indentation and extensive plasticity precede the transition to loss of stability driven by geometric nonlinearity and thermomechanical interaction effects. Finite element analyses that include both geometric and material nonlinearities provide results that correlate closely with the experimental observations. The work presented lays the foundation of a methodology for validating complex thermomechanical behaviour in sandwich structures using non-contact full-field measurement systems, and it demonstrates that analytical or numerical models based on the assumption of linear elastic material behaviour (such as the HSAPT model referenced in the paper) generally cannot adequately describe the thermomechanical behaviour of foam-cored sandwich structures.

We report an investigation of anisotropic magnetoresistance (AMR) and anomalous Hall resistance (AHR) of Rh and Pt thin films sputtered on epitaxial Y$_3$Fe$_5$O$_{12}$ (YIG) ferromagnetic insulator films. For the Pt/YIG hybrid, large spin-Hall magnetoresistance (SMR) along with a sizable conventional anisotropic magnetoresistance (CAMR) and a nontrivial temperature dependence of AHR were observed in the temperature range of 5-300 K. In contrast, a reduced SMR with negligible CAMR and AHR was found in Rh/YIG hybrid. Since CAMR and AHR are characteristics for all ferromagnetic metals, our results suggest that the Pt is likely magnetized by YIG due to the magnetic proximity effect (MPE) while Rh remains free of MPE. Thus the Rh/YIG hybrid could be an ideal model system to explore physics and devices associated with pure spin current., Comment: 7 pages, 4 figures

We report an investigation of transverse Hall resistance and longitudinal resistance on Pt thin films sputtered on epitaxial LaCoO$_3$ (LCO) ferromagnetic insulator films. The LaCoO$_3$ films were deposited on several single crystalline substrates [LaAlO$_3$ (LAO), (La,Sr)(Al,Ta)O$_3$ (LSAT), and SrTiO$_3$ (STO)] with (001) orientation. The physical properties of LaCoO$_3$ films were characterized by the measurements of magnetic and transport properties. The LaCoO$_3$ films undergo a paramagnetic to ferromagnetic (FM) transition at Curie temperatures ranging from 40 K to 85 K, below which the Pt/LCO hybrids exhibit significant extraordinary Hall resistance (EHR) up to 50 m$\Omega$ and unconventional magnetoresistance (UCMR) ratio $\Delta$$\rho$/$\rho_0$ about $1.2 \times 10^{-4}$, accompanied by the conventional magnetoresistance (CMR). The observed spin transport properties share some common features as well as some unique characteristics when compared with well-studied Y$_3$Fe$_5$O$_{12}$-based Pt thin films. Our findings call for new theories since the extraordinary Hall resistance and magnetoresistance cannot be consistently explained by the existing theories., Comment: 9 pages, 11 figures, accepted by Physical Review B

Some transition metal chlorides were used as promoters for homogeneous rhodium catalyzed methanol carbonylation. The experiments were carried out at low water conditions. All of the catalysts with the promoters demonstrate better catalytic activity than the pristine Monsanto catalyst. Ni, Fe and Co chlorides are most efficient promoters, among which Ni manifest the best performance in accelerating the catalytic rate. All the experiments promoted by such promoters demonstrate good stability and catalytic selectivity.

A robust capillary electrophoretic method has been established to separate aminosaccharides including glucosamine, galactosamine, N-methyl-glucamine, N-acetyl-glucosamine and amino glucuronic acid. All the aminosaccharides were dansylated fast under microwave irradiation at 385 W for 6 min (about 50-fold faster than common methods) and detected via on-line UV adsorption at 214 nm. Baseline separation of the dansylatied products was achieved in 20 min using a running buffer of 320 mM borate at pH 9.50. Quantitation of glucosamine in osteoarthritis tablets was then conducted. A linear working range was found in between 2.00 μg/mL and 1.80 mg/mL with linear regression coefficient of 0.9964. The limit of detection reached 1.00 μg/mL glucosamine (signal-to-noise, S/N = 3). Recoveries were determined by spiking a known amount of glucosamine in tablet-extracted solutions, giving a range of 88.0–99.7%. The run-to-run relative standard deviation was 0.24% (n = 5) for migration time and 2.72% for peak area.

A microwave-assisted method for rapid deposition of continuous gold films on glass substrates has been developed. Under microwave irradiation, gold nanoparticles in colloidal solutions were shown able to assemble on the naked substrates to form a gold monolayer within minutes. Images obtained by AFM revealed that the monolayer formed on the naked glass surface was much the same as that formed on the glass substrates pre-silanized with (3-aminopropyl)-trimethoxysilane. With this monolayer as seeds, further deposition of gold metal on the surface was thus possible and the thickness of the deposited gold was time-dependent as in the case of normal electroless plating. The sum time for preparing a 50-nm gold film on glass was about 15 minutes, much shorter than the existed electroless methods. Electrochemical experiments showed that the prepared gold films were continuous and can be used as stable electrodes able to sustain several hundreds of redox circulation. The quality of the films were also verified by surface plasmon resonance imaging (SPRI) studies and quite sharp pictures of protein dots were obtained, showing a smooth gold surface and proper film thickness were prepared.

We demonstrate that magnetic properties of ultra-thin Co films adjacent to Gd2O3 gate oxides can be directly manipulated by voltage. The Co films can be reversibly changed from an optimally-oxidized state with a strong perpendicular magnetic anisotropy to a metallic state with an in-plane magnetic anisotropy, or to an oxidized state with nearly zero magnetization, depending on the polarity and time duration of the applied electric fields. Consequently, an unprecedentedly large change of magnetic anisotropy energy up to 0.73 erg/cm2 has been realized in a nonvolatile manner using gate voltages of only a few volts. These results open a new route to achieve ultra-low energy magnetization manipulation in spintronic devices., 12 pages, 9 figures, including supplemental materials. Phys. Rev. Lett., in press (Editors' Suggestion, featured in Physics)

The present study aimed to identify the genes directly or indirectly correlated with the amplification of MYCN in neuroblastoma (NB). Microarray data (GSE53371) were downloaded from Gene Expression Omnibus, and included 10 NB cell lines with MYCN amplification and 10 NB cell lines with normal MYCN copy numbers. Differentially expressed genes (DEGs) were identified using the Linear Models for Microarray Data package, and a false discovery rate of0.05 and |log2FC (fold change)|1 were selected as cut‑off criteria. Hierarchical clustering analysis and Gene Ontology analysis were respectively performed for the DEGs using the Pheatmap package in R language and The Database for Annotation, Visualization and Integrated Discovery. A protein‑protein interaction network (PPI) was constructed for the DEGs using the Search Tool for the Retrieval of Interacting Genes database. Pathway analysis was performed for the DEGs in the PPI network using the WEB‑based GEne SeT AnaLysis Toolkit. The correlation between MYCN and the key gene associated with MYCN was determined using Pearson's correlation coefficient. In total, 137 downregulated and 35 upregulated DEGs were identified. Functional enrichment analysis indicated that KCNMB4 was involved in the regulation of action potential in neuron term, and the FOS, GLI3 and GLI1 genes were involved in the extracellular matrix‑receptor interaction pathway. The PPI network and correlation analysis revealed that the expression of SOX2 was directly correlated with the expression of MYCN, and the correlation coefficient of SOX2 and MYCN was ‑0.83. Therefore, SOX2, KCNMB4, FOS, GLI3 and GLI1 may be involved in the pathogenesis of NB, with the expression of SOX2 downregulating the expression of MYCN.

The electron momentum spectra of outer valence orbitals 9a1+5b2 of thiophene (C4H4S) have been studied by binary (e, 2e) electron momentum spectroscopy (EMS), at an impact energy of 1200 eV plus binding energy, and symmetric non-coplanar kinematics. The experimental momentum profile of the summed orbitals is compared with the theoretical momentum distributions calculated using Hartree-Fock (HF) and density functional theory (DFT) methods with various basis sets. The experimental measurement is well described by the HF and DFT calculations, and the calculations using the larger basis sets including diffuse and polarization functions give better descriptions of experiments.

The component of the traditional Chinese medicine (TCM) can be influenced by soil, climate, and growth stage, and fingerprint is an important means in its quality control. Our previous studies showed that high-speed counter-current chromatography (HSCCC) was helpful in the development of fingerprint of TCM. Since the HSCCC method is new, it is necessary to compare it with conventional ones, such as high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC) and high-performance capillary electrophoresis (HPCE). Comparison with HPLC was conducted in our previous study. In this study, HSCCC was compared with non-aqueous capillary electrophoresis (NACE). With NACE, seven stable components were separated within 55 min, respectively, from three crude samples of Salvia miltiorrhiza Bunge from different growth locations. In HSCCC separation, 12 components were separated, respectively, with good correspondence and precision within 13 h. Both NACE and HSCCC were effective in showing whole concentration distribution of all kinds of constituents. Principles of these two methods were very different, which led to different elution sequences and relative contents of peaks. HSCCC showed better performance in analysis of tanshinones, which made its fingerprint containing more chemical information than that of NACE. It was further proven that HSCCC could be a feasible and cost-effective method in the development of the fingerprint of TCM.

The highest occupied molecular orbital (HOMO) of cyclopentene (C 5 H 8 ) has been studied by a binary (e, 2e) electron momentum spectroscopy, at an impact energy of 1200 eV plus the binding energy and using symmetric non-coplanar kinematics. The first measurements of the complete valence shell binding energy spectra and the HOMO momentum profile are reported. The experimental momentum profile of HOMO is compared with the theoretical momentum profiles calculated using Hartree–Fock and density functional theory method with various basis sets. The EMS experimental result is well described by the calculations.

At the interfaces between the metallic electrodes and barrier in magnetic tunnel junctions it is possible for localized states to form which are orthogonal to the itinerant states for the junction, as well as resonant states that can form at the interfaces. These states form highly conducting paths across the barrier when their orbitals point directly into the barrier; these paths are in addition to those formed by the itinerant states across the entire junction. Most calculations of transport in magnetic tunnel junctions are made with the assumptions that the transverse momentum of the tunnelling electrons is conserved, in which case the itinerant electron states remain orthogonal to localized states. In principle it is possible to include diffuse scattering in both the bulk of the electrodes and the barrier so that the transverse momentum is not conserved, as well as the processes that couple localized states at the electrode-barrier interface to the itinerant states in the bulk of the electrodes. Howev...

A comprehensive chemical and structural analysis is made of a new type of trititanate nanotube, which is synthesized via the reaction of TiO2 particles with NaOH aqueous solution. It is found that the trititanate nanotubes are multi-walled scroll nanotubes with an inter-shell spacing of about 0.78 nm and an average diameter of about 9 nm. An atomic model of the nanotube is derived based on information from powder X-ray diffraction, selective-area electron diffraction, high-resolution electron microscopy and structure simulations. A model nanotube may be constructed by wrapping a (100) sheet of H2Ti3O7 along [001] with the tube axis parallel to [010].

In conventional calculations of transport in magnetic tunnel junctions, one usually assumes that the transverse momentum of the tunnelling electrons is conserved and that the itinerant electron states are orthogonal to localized states. However, in most of the junctions studied, there is diffuse scattering in both the bulk of the electrodes and the barrier so that the transverse momentum is not conserved, and there are processes that couple localized states at the electrode-barrier interface to the itinerant states in the bulk of the electrodes. While it is in principle possible to include these effects, it leads to lengthy calculations. Here we propose an approximate scheme in which we do not take explicit account of either of the effects mentioned above, but in which we calculate the tunnelling through all the states that exist at the electrode-barrier interfaces. We compare the k∥-resolved density of states and tunnelling currents across a junction in our approximate scheme with that found usi...

A new fluorescent probe based on ensemble of gold nanoclusters (AuNCs) and polymer protected gold nanoparticles (AuNPs) for turn-on sensing of L-cysteine was designed and prepared. The AuNCs were protected by bovine serum albumin and had strong fluorescence. The polymer protected AuNPs were synthesized by a facile in situ strategy at room temperature and could quench the fluorescence of AuNCs due to the Forster resonance energy transfer. Interestingly, it has been observed that the quenched fluorescence of AuNCs was recovered by L-cysteine, which could induce the aggregation of polymer protected AuNPs by sulfur group. Then the prepared fluorescent probe was successfully used for determination of L-Cys in human urines, which would have an evolving aspect and promote the subsequent exploration. (C) 2015 Elsevier B.V. All rights reserved.

Cerebral artery stenosis is known as an important cause of stroke, and elevated fasting glucose level is also considered as a risk factor for stroke. Our aim was to exam whether elevated fasting glucose is associated with cerebral artery stenosis, especially asymptomatic cerebral artery stenosis.The current study included 5309 participants who were age of 40 years or older, and free of stroke, transient ischemic attack, and coronary artery disease. Cerebral artery stenosis was assessed by Doppler ultrasound. Participants were classified into four subtypes: no cerebral artery stenosis (NCS), intracranial artery stenosis (ICAS), extracranial carotid artery stenosis (ECCS) and combined intracranial artery and extracranial carotid artery stenosis (IECS). Fasting blood glucose concentrations were grouped into: normal fasting glucose (5.60 mmol/l), impaired fasting glucose 1 (IFG1) (5.60-6.09 mmol/l), IFG2 (6.10-6.99 mmol/l) and diabetes (≥ 7.00 mmol/l). A multinomial logistic regression was used to examine the association between fasting glucose and cerebral artery stenosis, after adjusting for potential confounders.Fasting glucose level was significantly higher in ICAS and IECS groups than the other two groups. In the multinomial logistic regression analysis, IFG2 was the risk factor for ICAS (odds ratio (OR) 1.53, 95% confidential interval (CI), 1.12-2.10), and diabetes was a strong predictor for both ICAS (OR 1.75, 95% CI, 1.38-2.22) and IECS (OR 2.14, 95% CI 1.31-3.49). However, fasting glucose level was not significantly associated with ECCS.Our results showed that elevated fasting glucose levels are associated with asymptomatic cerebral artery stenosis, especially ICAS and IECS.

The magnetization reversal of polycrystalline ferromagnetic-antiferromagnetic bilayers is investigated by employing the Landau-Lifshitz-Gilbert equation. The magnetic interaction at the interface is modeled by a random field. It is found that the random field breaks the ferromagnetic layer into domains during magnetization reversal. The domain size is usually much smaller than that without the underlying antiferromagnetic layers. We quantitatively determine the enhanced coercivity as a function of the thickness of the ferromagnetic layer, the grain size, and the interface random field.

We have examined electron screening at the surface of a ferromagnetic metal. In an applied electric field, the surface develops an induced charge and magnetization. This can be described in terms of a novel spin-dependent screening electric field. A set of integrodifferential equations for screening potentials is derived and solved in some limiting cases. The significant implication relevant to spin-polarized transport in field emission and in magnetic tunnel junctions is discussed.

During the past four years, researchers made significant advances in fabricating magnetic tunnel junctions with reproducible magnetic and magnetotransport properties. Important developments include optimization of oxidation processes, discovery of new class of magnetic tunnel junctions, combination of spin dependent tunneling with the Coulomb blockade effect, and a better theoretical understanding of the I – V characteristics of magnetic tunnel junctions. These developments make them promising candidates for magnetic random access memories.

To assess the effect of electronic structure of magnetic electrodes on the magnetoresistance of tunnel junctions (JMR) we made ab initio calculations of the electronic structure of BCC(1 0 0) Fe, and FCC(1 0 0) Co and Ni electrodes. We treat hopping to and propagation in the barrier as adjustable parameters and discuss features of the JMR attributable to the electronic structure of the electrodes.

We report on the correlation between unidirectional and uniaxial anisotropy in exchange-biased ferromagnetic Permalloy layers. The dependence of exchange bias and coercivity on temperature and the antiferromagnetic and ferromagnetic layer thickness was studied and compared with the predictions of different theoretical models. A thorough explanation of the experimental data is provided by theoretical extension of Malozemoff's model.

Domain walls in ferromagnetic metals are known to be a source of resistance since the early experiments on iron whiskers. Recently it has been possible to identify this contribution from data on cobalt and nickel films which display stripe domains in which the current is driven normal to the domain walls. With the same Hamiltonian as used to explain giant magnetoresistance in structures with collinear magnetic alignments we have determined the spin flip, as well as nonflip, scattering present in domain walls. We calculate the resistivity in zero field, i.e., in the presence of striped domains, and at saturation to show the amount of magnetoresistance that is attributable to domain wall scattering.

A zero bias anomaly is observed at low temperatures in the current-voltage characteristics of ferromagnetic tunnel junctions; the drop in the junction resistance with increasing bias voltage is greater for antiparallel alignment of the magnetic moments of the magnetic electrodes than for parallel alignment. The resulting decrease in the magnetoresistance of the junction is accounted for by spin excitations localized at the interfaces between the magnetic electrodes and the tunnel barrier.

Pretreatment with scutellaria baicalensis stem-leaf total flavonoid has protective effects against ischemia and attenuates myocardial ischemia-reperfusion injury. In this study, rats were given scutellaria baicalensis stem-leaf total flavonoid intragastrically at 50, 100, and 200 mg/kg per day for 7 days before focal cerebral ischemia-reperfusion injury models were established using the suture method. We then determined the protective effects of scutellaria baicalensis stem-leaf total flavonoid pretreatment on focal cerebral ischemia-reperfusion injury. Results showed that neurological deficit scores increased, infarct volumes enlarged, apoptosis increased and Bcl-2 and Bax protein expression were upregulated at 24 hours after reperfusion. Pretreatment with scutellaria baicalensis stem-leaf total flavonoid at any dose lowered the neurological deficit scores, reduced the infarct volume, prevented apoptosis in hippocampal cells, attenuated neuronal and blood-brain barrier damage and upregulated Bcl-2 protein expression but inhibited Bax protein expression. Doses of 100 and 200 mg/kg were the most efficacious. Our findings indicate that pretreatment with scutellaria baicalensis stem-leaf total flavonoid at 100 and 200 mg/kg can improve the neurological functions and have preventive and protective roles after focal cerebral ischemia-reperfusion injury.

This method is based on the use of aromatic sodium sulfinates as aryl sources, affording diarylmethanes in moderate to good yields via extrusion of SO2.

This paper presents a primarily experimental investigation of the instability behaviour of polymer foam cored sandwich structures loaded at elevated temperatures. An experimental setup was designed to induce the unstable behaviour using sandwich beam specimens subjected to four-point bending and by imposing a linear temperature gradient through the core thickness. A wavy deformation of the face-sheet was observed using high-speed imaging combined with digital image correlation (DIC) for the specimens tested at elevated temperatures over 70°C, thus identifying the occurrence of face-sheet wrinkling. The face-sheet wavy deformation evolves to core crushing in tens of microseconds and thereby the high-speed imaging is essential in this work. The experimental results shows that the failure mode of the specific polymer foam cored sandwich beam specimens shifts from face-sheet yielding to face-sheet wrinkling as the temperature increases, and this is shown to agree well with analytical and numerical predictions.

A palladium-catalyzed approach for the synthesis of diarylmethanes from sodium sulfinates and benzyl chlorides is described. Various aromatic sodium sulfinates were used as aryl sources via extrusion of SO2 and gave the diarylmethanes in moderate to good yields.

Objectives To investigate the relationship between ideal cardiovascular health metrics (including smoking, body mass index, dietary intake, physical activity, blood pressure, total cholesterol and fasting blood glucose) and risk of stroke. Background Previous studies showed a strong relationship between the number of ideal cardiovascular health metrics and lower risk of cardiovascular diseases and stroke. However, little is known regarding its relationship with ischemic and hemorrhagic stroke risk respectively. Methods We collected information on the ideal cardiovascular health metrics among 91,698 participants (18-98 years old; 72826 men and 18872 women) free of myocardial infarction and stroke at baseline (2006-07) in the Kailuan cohort study, China. We then prospectively investigated the association between ideal cardiovascular health metrics and risk of stroke. Results During four years of follow-up, we identified 1443 incident strokes (1057 ischemic and 386 intracerebral hemorrhagic). The multivariate-adjusted hazard ratios for total stroke with adherence to 0 (reference), 1, 2, 3, 4, 5, and 6 or 7 ideal health metrics were 1, 0.91, 0.69, 0.51, 0.37, 0.28, and 0.25 (95% confidence interval: 0.11-0.55; p-trend Conclusions We observed a clear inverse dose-response relationship between the number of ideal cardiovascular health metrics and risk of stroke in a Chinese population, which supports the importance of ideal health behaviors and factors in the prevention of stroke.

BACKGROUND AND PURPOSE: Intracranial Artery Stenosis (ICAS) is one of the most common causes of ischemic stroke in Asia. Previous studies have shown the number of ideal cardiovascular health (CVH) metrics was associated with lower risk of stroke. This study aimed to investigate the relationship between ideal CVH metrics and prevalence of ICAS. METHODS: A random sample of 5,412 participants (selected from Kailuan Study as a reference population) aged 40 years or older (40.10% women), free of stroke, transient ischemic attack, and coronary disease, were enrolled in the Asymptomatic Polyvascular Abnormalities Community study from 2010 to 2011. We collected information on the seven CVH metrics (including smoking, body mass index, dietary intake, physical activity, blood pressure, total cholesterol and fasting blood glucose); and assessed ICAS by transcranial Doppler. The relationship between the ideal CVH metrics and prevalence of ICAS was analyzed using the multivariate logistic regression. RESULTS: After adjusting for age, sex, and other potential confounders, the adjusted odds ratios(95% confidence interval) for ICAS were 0.76(0.58-0.99), 0.55(0.43-0.72), 0.49(0.37-0.65), 0.43(0.31-0.61), and 0.36(0.22-0.62), respectively, for those having 2, 3, 4, 5, and 6-7 ideal CVH metrics compared with those having 0-1 ideal metric(p-trend

We review the current theoretical understanding of giant magnetoresistance in magnetic multilayered structures. The active ingredients producing magnetoresistance for current in and perpendicular to the plane of the layers are discussed, and the effect of superlattice band structure on transport is reviewed. Differences between ballistic and diffusive electron transport are highlighted. The effective fields used to account for vertex corrections for current perpendicular to the layers is discussed and their meaning is defined.

Most discussions of giant magnetoresistance (GMR) have focused on collinear cases where the magnetizations in adjacent layers are either parallel or antiparallel. To explore the relative importance of the superlattice potential and of the impurity scattering on the angular dependence of GMR, we calculate the electrical resistivity for noncollinear magnetizations. The electronic structure of the superlattice is modeled by a Kronig-Penney potential. When the magnetizations of the adjacent layers are neither parallel nor antiparallel, spinor forms of Bloch states and dispersion relations are derived. Then the conductivity as a function of the angle between magnetization directions of adjacent layers is calculated in the homogeneous limit where the mean free path is much larger than the layer thickness. We find the angular dependence of the resistivity and hence of the GMR for current in the plane of layers and perpendicular to the plane of the layers depends on the spin-dependent superlattice potential, and the details of the scattering potential. \textcopyright{} 1996 The American Physical Society.

We review the basic concepts that have been developed to understand the magnetoresistance of transition-metal multilayers, and we present some unsolved issues that relate to features of the electronic structures that are observed in transport measurements. We discuss how close current models are to describing the magnetotransport in real multilayers.

Recently corrugated multilayered structures of Cu/Co/Cu/NiFe have been grown on silicon substrates which have (111) faceted grooves etched on their surface. These structures can be probed by conventional means with current at an angle to the plane of layers (CAP) as well as for currents in the plane. The CAP magnetoresistance (MR) has been found to be up to 50% greater than that for currents in the plane of the layers (CIP). We have derived the relation between the resistivities for CIP, CAP, and CPP (currents perpendicular to the plane of layers), in terms of the angle between the current and planes of the layers. From the measurement of the CIP and CAP-MR's we predict the CPP-MR for these structures.

National Natural Science foundation of China [11274321, 11404349, 51502314, 51522105, 11374312]; Key Research Program of the Chinese Academy of Sciences [KJZD-EW-M05]; U.S. National Science Foundation [ECCS-1404542]

Giant magnetoresistance has been observed in both magnetic multilayers and magnetic granular solids. We develop a framework for unifying these particular realizations of inhomogeneous magnetic media, based on the real-space Kubo formula. It constitutes a spin-dependent form of linear response theory, associated with internal spin-dependent fields arising from spin accumulation; moreover, we discuss the physical meaning of these spin dependences. For magnetic multilayers we discuss the particular cases of collinear and noncollinear configurations, and we consider limiting cases of the elastic mean-free path to inhomogeneity-scale ratio for granular solids. Furthermore, we introduce the concept of magnetically self-averaging systems, which include the current perpendicular to the plane geometry of multilayers and granular solids. In the limit of no spin-flip scattering, we show that there are no length scales associated with the magnetoresistance of self-averaging structures.

We investigate spin-current transport with an antiferromagnetic insulator NiO thin layer by means of the spin-Hall magnetoresistance (SMR) over a wide range of temperature in Pt/NiO/Y3Fe5O12 (Pt/NiO/YIG) heterostructures. The SMR signal is comparable to that without the NiO layer as long as the temperature is near or above the blocking temperature of the NiO, indicating that the magnetic fluctuation of the insulating NiO is essential for transmitting the spin current from the Pt to YIG layer. On the other hand, the SMR signal becomes negligibly small at low temperature, and both conventional anisotropic magnetoresistance and the anomalous Hall resistance are extremely small at any temperature, implying that the insertion of the NiO has completely suppressed the Pt magnetization induced by the YIG magnetic proximity effect (MPE). The dual roles of the thin NiO layer are, to suppress the magnetic interaction or MPE between Pt and YIG, and to maintain efficient spin current transmission at high temperature.

We review the key ingredients of our current theoretical formulation of spin-dependent transport in magnetic layered and granular solids. The meaning of effective spin-dependent internal electric field is given, and the shortcomings of current approaches are signaled. The essential features of realistic model calculations of conduction in magnetically inhomogeneous systems are discussed.

Single crystals of the title compound with sizes up to 34 x 34 x 16 mm3 are prepared by the top-seeded solution growth method using a 2:1 mixture of NaF and LiCl as a flux.

An efficient method was developed for the desulfitative arylation of indoles with sodium sulfinates using palladium as catalyst and copper chloride dihydrate as oxidant. The direct arylation occurred exclusively in the C-2 position of indoles and proceeded well for a range of different substrates.

Intracranial artery stenosis may be the most frequent cause of ischemic stroke in the world. Early detection of asymptomatic intracranial artery stenosis may allow for therapeutic intervention. Most elements of the Framingham stroke risk profile (FSRP) are also risk factors for intracranial artery stenosis. Thus, the FSRP might play a role in detecting asymptomatic intracranial artery stenosis.To investigate the relationship between the FSRP and asymptomatic intracranial artery stenosis.A sample of 5852 subjects (age40 years) was selected from the KaiLuan study. All participants received transcranial Doppler ultrasound examinations to detect the presence and quantify the severity of intracranial arterial stenosis. Demographic and clinical variables were investigated at the time of examination. Binary logistic regression analyses was performed to determine the odds ratio of FSRP components to asymptomatic intracranial stenosis before and after adjusted for gender, body mass index (BMI), and total cholesterol (TC).The subjects with intracranial artery stenosis were older than those without (68·2 versus 64·9), and the systolic blood pressure was higher in those with intracranial artery stenosis (146·86 versus 136·39). Among intracranial artery stenosis subjects, 77·5% had hypertension, 26·1% had diabetes, 8·9% had left ventricular hypertrophy, and 4·8% had atrial fibrillation. Logistic regression analyses revealed that age, systolic blood pressure, diabetes, atrial fibrillation, and left ventricular hypertrophy were risk factors for intracranial artery stenosis. The incidence of asymptomatic intracranial artery stenosis correlated with increasing FSRP scores. The odds ratios of intracranial artery stenosis from the lowest to the highest FSRP quartiles were as follows: 1 (reference group), 1·77 (95% CI: 1·23-2·56), 2·84 (95% CI: 2·02-3·98), 5·65 (95% CI: 4·03-7·93).FSRP plays an important role in detecting asymptomatic intracranial artery stenosis.

By using the quantum kinetic approach with the instantaneous local equilibrium approximation, we propose an equation that is capable of addressing magnetization dynamics for a wide range of temperatures. The equation reduces to the Landau-Lifshitz equation at low temperatures and to the paramagnetic Bloch equation at high temperatures. Near the Curie temperature, the magnetization reversal and dynamics depend on both transverse and longitudinal relaxations. We further include the stochastic fields in the dynamic equation in order to take into account fluctuation at high temperatures. Our proposed equation may be broadly used for modeling laser pump-probe experiments and heat assisted magnetic recording.

Laser-induced demagnetization is theoretically studied by explicitly taking into account interactions among electrons, spins and lattice. Assuming that the demagnetization processes take place during the thermalization of the sub-systems, the temperature dynamics is given by the energy transfer between the thermalized interacting baths. These energy transfers are accounted for explicitly through electron-magnons and electron-phonons interaction, which govern the demagnetization time scale. By properly treating the spin system in a self-consistent random phase approximation, we derive magnetization dynamic equations for a broad range of temperature. The dependence of demagnetization on the temperature and pumping laser intensity is calculated in detail. In particular, we show several salient features for understanding magnetization dynamics near the Curie temperature. While the critical slowdown in dynamics occurs, we find that an external magnetic field can restore the fast dynamics. We discuss the implication of the fast dynamics in the application of heat assisted magnetic recording., Comment: 11 Pages, 7 Figures