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A rotating field method was applied to separate linear and quadratic magneto-optic Kerr effects (MOKE) of Fe/GaAs(001) and Fe/MgO/GaAs(001) epitaxial films, and two quadratic MOKE terms could be quantitatively separated. The linear MOKE was independent of crystal orientation, but the quadratic MOKE showed a sinusoidal relationship with a 90° period. The experimental results are fully consistent with theory based on the transfer matrix method. [ABSTRACT FROM AUTHOR]

Background: The correlation between the increased mean platelet volume and varicocele is controversial. Objectives: We designed this research to demonstrate the correlation relationship between varicocele and mean platelet volume by studying the changes of mean platelet volume in patients with varicocele before and after operation. Materials and methods: A total of 317 patients with left unilateral varicocele underwent operation, and 293 healthy adult males were enrolled in the study. We collected diagnostic data for preoperative patients through physical examination, color Doppler ultrasonography, and blood routine, and recorded the follow‐up data at 6 months after operation for varicocele. Platelet indices and the degree of varicocele or the diameter of spermatic vein correlation analysis were performed. Mean platelet volume values of preoperative and 6‐month postoperative were statistically evaluated. Results: We found that the degree of varicocele and the diameter of spermatic vein were positively correlated with mean platelet volume (p = 0.001 or p < 0.001). When the left unilateral varicocele patients and healthy subjects were compared, there was a significant increase in mean platelet volume (p = 0.003). Mean platelet volume values of 96 varicocele patients who were cured by operation for varicocele after 6 months were decreased significantly more than preoperative (p = 0.039), but 32 varicocele patients of 6‐month postoperative recurrence could not prove this change (p = 0.930). Discussion and conclusion: Our research proves that mean platelet volume was positively correlated with the degree of varicocele and the diameter of spermatic vein and varicocele patients showed significantly higher mean platelet volume than healthy subjects. The mean platelet volume of varicocele patients cured by operation for varicocele after 6 months was lower than before, but there was no difference in mean platelet volume between 6‐month postoperative recurrent patients with preoperative. [ABSTRACT FROM AUTHOR]

The dependence of magnetic anisotropy, magnetic domain patterns and magnetization reversal processes in [Pt/Co(tCo)/Cu]10 film stack epitaxied on Cu (111) substrate have been studied as a function of the Co layer thickness tCo, by magneto-optic polar Kerr magnetometry and microscopy. We find the film undergoes spin reorientation transition from out-of-plane to in-plane as tCo increases. The SRT thickness is verified by Rotating-field Magneto-Optic Kerr effect method. The film exhibits the stripe domain structures at remanence with the width decreasing while tCo approaches SRT. As demonstrated by the first order reversal curve measurement, the magnetization reversal process encompasses irreversible domain nucleation, domain annihilation at large field and reversible domain switching near remanence. [ABSTRACT FROM AUTHOR]

We investigated the magneto-optical Kerr effects in C2v symmetric Fe/GaAs(110) film and quantitatively separated the linear and quadratic Kerr contributions with the rotating field method. The linear Kerr effect was experimentally found to have twofold anisotropy with crystal orientation, in well agreement with the theoretical prediction. In addition, the quadratic Kerr effects exhibit both twofold and fourfold anisotropy. The calculation based on a 4×4 transfer matrix method indicates that the anisotropies of the linear and quadratic Kerr effects both originate from the second order magneto-optical coupling. The C2v symmetric film with anisotropic linear Kerr effect may have a potential application on the future precise magneto-optical sensors. [ABSTRACT FROM AUTHOR]

This paper explores some of the applications of Boltzmann models in the hydraulic field. A finite volume scheme with fluxes evaluated based on the solution of the Bhatnagar–Gross-Krook (BGK) Boltzmann equation for surface water flows is obtained. The consistency of the BGK equation with the classical mass and momentum equations for shallow water flow in two-lateral dimensional systems is shown. Turbulence models are incorporated through the collision time. The model is applied to a wide range of problems in surface water hydraulics including circular dam break (bore), roll waves, shallow wakes and shallow mixing layers. Where possible, model results are compared to experimental data. [ABSTRACT FROM AUTHOR]

In this paper it is proved that a space may be realized as the set of the maximal elements in a continuous poset if and only if it is Tychonoff. [ABSTRACT FROM AUTHOR]

BSTRACT: The antioxidant efficiency of ascorbic acid, α-tocopherol, Trolox C, and catechin were evaluated for chicken breast meat in a dispersion system at 37 °C. Peroxidation was induced by adding different kinds of initiators. The initiators exhibited the following order of catalytic action: ascorbic acid/Fe2+ > hemoglobin > Cu+/H2O2 > 2,2′-azobis (2-amidinopropane) hydrochloride (AAPH). The antioxidant efficiency of the antioxidants tested depended on their phase distribution and their reactivity to the radicals in various initiation systems. Among the antioxidants tested, catechin was the most effective antioxidant for chicken breast meat oxidation under the experimental conditions. [ABSTRACT FROM AUTHOR]

The in-plane magnetic anisotropy of Fe films fabricated with thermal deposition (TD) and pulse laser deposition (PLD) techniques on GaAs(001) substrate was studied quantitatively. The volume anisotropy in TD Fe film is attributed to the constant strain anisotropy, supported by reflection high-energy electron diffraction analysis. The PLD growth was found to deeply influence the interface anisotropy at Fe/GaAs interface even through a 30 ML Fe TD underlayer. The volume anisotropy was found to exist in TD Fe film even grown on top of a PLD film. Our study indicates that the uniaxial magnetic anisotropy in Fe/GaAs(001) system can be controlled by a combination of TD and PLD growth. [ABSTRACT FROM AUTHOR]

The interaction between surface gravity waves and a vertical wall-mounted rigid cylindrical structure such as a pier or vegetation involves various interdependent physical phenomena including the scouring process and the vertical mixing and horizontal dispersion of materials. As a step toward understanding this interaction, detailed flow fields of sinusoidal oscillatory flow passing a vertical wall-mounted cylinder are numerically investigated for three different wave conditions. With a moderately wide range of the Keulegan–Carpenter number from 6 to 20, numerical simulations are systematically performed, and the data are extensively investigated to determine the dynamic characteristics of the oscillatory flow past a wall-mounted cylinder. In this study, three-dimensional unsteady incompressible Navier–Stokes equations are solved using the open-source software, OpenFOAM®. Grid-convergence tests are conducted, and the undisturbed oscillating Stokes boundary-layer determined by numerical simulations is validated by a good agreement with the analytical solution. Flow details in the form of profiles, streamlines, and contours of calculated turbulence fields are presented. Coherent structure dynamics is illustrated using iso-surfaces of the Q-criterion. The synthesis of various flow variables presents a mechanistic view of the bed shear and processes responsible for scour near the cylinder-wall junction. [ABSTRACT FROM AUTHOR]

This study applies the Dynamic Mode Decomposition (DMD) to better understand and model the oscillatory flow across a vertical wall-mounted cylinder. At different Keulegan–Carpenter numbers, three-dimensional direct numerical simulations are performed to provide the flow details such as the snapshots of the coherent structures around the cylinder, vorticity fields, and bed shear stress. The selected fields are decomposed into dynamic modes. The characteristic flow features with relevant information including spatial mode shape, frequency, and mode amplitude are systematically investigated. The time series of flow fields is also reconstructed using the DMD analysis and compared against the original data to assess the efficacy of information in the low-dimensional system. The results show that the DMD analysis can capture the dynamic and nonlinear features of the oscillatory flow past the vertical wall-mounted cylinder and also efficiently reconstruct the relevant fields with reasonable accuracy. It provides a basis for the data-driven model of scour near the cylinder–wall junction relevant to coastal engineering applications. [ABSTRACT FROM AUTHOR]

Three-dimensional printed multicolor normal and abnormal fetal hearts based on ultrasound imaging data Chen I et al i . reported a case in which 3D printing was used to model a complete normal fetal heart, which demonstrated the feasibility of 3D printing of a small fast-moving fetal anatomical structure without a rest period, based only on 3D ultrasound imaging data[5]. Here, we present two 3D printed multicolor fetal heart models, one of a normal heart and the other of a heart with tetralogy of Fallot, demonstrating the technical feasibility of 3D modeling and 3D printing of normal and abnormal fetal hearts based on ultrasound imaging data. [Extracted from the article]

This study provided a thorough investigation of surface blistering and exfoliation behavior in germanium substrates with different crystal orientation, which is crucial for understanding the mechanism of smart-cut process in the fabrication of germanium-on-insulator. Two hundred-kilo-electron-volt H2+ ions with a fluence of 2.5 × 1016 ions/cm2 were implanted into (100)-oriented, (111)-oriented, and (110)-oriented n-type germanium wafers. Following ion implantation, the post-annealing treatments were conducted to drive the formation of blisters and craters in germanium. In conducting the characteristic analysis, hydrogen depth profiles were measured using SIMS. In situ optical microscopy observation was performed to measure the threshold temperature and onset time of the blisters and craters. Cross-sectional transmission electron microscopy was also employed to examine the micro-structural properties of hydrogen-induced radiation defects in the specimens. The kinetics of the thermally activated blistering process was also analyzed to estimate the effective activation energy for blister and crater formation. The results revealed that an obviously different morphology of the optically detectable blisters and craters can be identified in Ge(100), Ge(111), and Ge(110) specimens. Substrate orientation of germanium also makes a great impact on the blistering threshold temperature, the onset time and activation energy for blister and crater formation, and the development of hydrogen implantation-induced micro-cracks. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Phase change memory has been considered as one of the most promising alternatives for next-generation nonvolatile semiconductor memory. Modification of phase change materials by impurity doping has been proved to be an effective way to improve phase change memory device performance. In this study, the most common phase change material, Ge2Sb2Te5 (GST), was employed, and its intrinsic properties were modified using boron-ion implantation. The GST films were implanted with 20 keV boron ions to fluences of 5 × 1014 and 5 × 1015 ions/cm2. The characteristics of the virgin and boron-implanted GST films were investigated by SIMS, XRD, and in situ resistance measurement. The kinetics of the thermally activated phase transition was also analyzed on the basis of the Arrhenius relationship. The results revealed that both crystallization temperature and activation energy of crystallization increase with increasing the boron fluence. The data retention capability is also enhanced from 83 to 88 °C, corresponding to a criterion of 10-year archival lifetime. In addition, the XRD spectra indicated that high-fluence boron-ion implantation partially inhibits the transition of the GST films from face-centered cubic phase to hexagonal close-packed phase. In conclusion, the thermal stability of the GST films can be improved through boron-ion implantation. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We studied angle-dependent magnetoresistance in Pt/Fe3O4 bilayers at room temperature. Based on field-dependent and angle-dependent measurements, we show that spin Hall magnetoresistance (SMR) exists in the Pt/Fe3O4 system at room temperature, although the Fe3O4 layer is not a good insulator. The SMR contribution inPt/Fe3O4 can be clearly identified for thin enough Fe3O4 films. Moreover, the SMR in Pt/Fe3O4 does not rely on the current direction, which is different from the anisotropic magnetoresistance in single-crystalline Fe3O4 films. [ABSTRACT FROM AUTHOR]

Aim: To construct a novel nomogram by integrating computed tomography perfusion (CTP) and clinical parameters for individualised prediction of haemorrhagic transformation (HT) in intravenous thrombolysis (IVT)-treated acute ischaemic stroke (AIS) patients.Methods: Anterior circulation AIS patients who underwent IVT at a single centre from January 2018 to June 2020 were reviewed retrospectively. The CTP parameters of two regions of interest (ROI), the entire perfusion lesion areas, and the infract core areas, were assessed. HT was documented by follow-up CT 24 ± 2 h after IVT. Multivariable logistic regression was conducted by including clinical variables and CTP parameters to identify the independent predictors of HT. A nomogram was developed based on the independent predictors. The discriminative value and calibration of the nomogram were tested by concordance indexes (C-indexes) and calibration plots. Internal validation was performed using fivefold cross-validation.Results: The nomogram was generated using the complete data from 341 patients. Seven variables were included in the final nomogram, including: the relative cerebral blood volume (rCBV), permeability surface (PS), and relative PS (rPS) in infract core areas, the relative time to maximum (rTmax) and rPS in entire perfusion lesion areas, the National Institutes of Health Stroke Scale (NIHSS), and atrial fibrillation (AF). The C-indexes were 0.815 and 0.817 for the nomogram and internal validation. The calibration plots showed excellent agreement.Conclusion: This is the first study establishing a nomogram based on CTP and clinical parameters to predict HT after stroke thrombolysis. [ABSTRACT FROM AUTHOR]

Using first-principles method and Boltzmann theory, we provide an accurate prediction of the electronic band structure and thermoelectric transport properties of α-MgAgSb. Our calculations demonstrate that only when an appropriate exchange-correlation functional is chosen can we correctly reproduce the semiconducting nature of this compound. By fine tuning the carrier concentration, the thermoelectric performance of α-MgAgSb can be significantly optimized, which exhibits a strong temperature dependence and gives a maximum ZT value of 1.7 at 550 K. We also provide a simple map by which one can efficiently find the best doping atoms and optimal doping content. [ABSTRACT FROM AUTHOR]

Gravity dams are important infrastructures, and their failure can affect public security. In this work, physical modeling was conducted to determine the dynamic responses and types of damage to gravity dams subjected to underwater explosions. Five tests under different impoundment levels, centrifugal accelerations, standoff distances, detonation depth, and equivalent weights were performed in a centrifuge. The mechanism of dynamic responses of the dam was analyzed. The peak strain and displacement by the shock wave and bubble pulse were both reached when the impulses of the dynamic loads were maximum. Different failure modes and degrees of damage were observed in the tests. When the explosive detonated in shallow water, a more substantial structural bending moment was generated by the shock wave to cause structural failure by bending. When the impoundment level was reduced, the dynamic responses were reduced due to the decrease in shock energy or impulse on the structure. However, new deformation or failure mode can be induced when the impoundment level is lower. Better understanding of the dynamic mechanism and proper control of the impoundment level would be helpful for dam protection. [ABSTRACT FROM AUTHOR]

Aim: To explore in a laboratory setting the feasibility of using Meglumine Diatrizoate (MD) to improve the accuracy of diagnosis of cracked teeth on cone‐beam CT (CBCT) images. Methodology: Twenty‐four teeth were cracked artificially by soaking them cyclically in liquid nitrogen and hot water. The number and position of crack lines were evaluated with a dental operating microscope and used as the gold standard. The artificially cracked teeth were then examined using routine scanning (RS) and enhanced scanning (ES) modes, respectively. For the ES mode, MD was painted on the surface of the crack lines, and then, CBCT scanning with the same parameters was performed after 10 min. A radiological graduate student and an experienced radiologist evaluated the presence or absence of crack lines, respectively. The differences between the RS and ES modes were determined and assessed using McNemar's test. Inter‐examiner agreement and intra‐examiner agreement were assessed using kappa analysis. Results: Fifty‐seven crack lines were found in the 24 cracked teeth. In the RS mode, the accuracy of detection of crack lines was 23% (radiological graduate student) and 32% (experienced radiologist), whereas in the ES mode, the accuracy was 61% (radiological graduate student) and 65% (experienced radiologist). The inter‐examiner agreement was 0.693 in RS mode and 0.849 in ES mode. The intra‐examiner agreement was 0.872 and 0.949 for the radiological graduate student in RS and ES mode respectively; and one for the experienced radiologist both in RS and ES mode. Conclusions: Compared with routine scanning mode, more crack lines could be detected in enhanced scanning mode using Meglumine Diatrizoate as a contrast medium. MD could be a potential contrast medium to improve the accuracy of detection of crack lines on CBCT images. [ABSTRACT FROM AUTHOR]

Magnetization reversal of interconnected kagome artificial spin ice was studied by the first-order reversal curve (FORC) technique based on the magneto-optical Kerr effect and magnetoresistance measurements. The magnetization reversal exhibits a distinct sixfold symmetry with the external field orientation. When the field is parallel to one of the nano-bar branches, the domain nucleation/propagation and annihilation processes sensitively depend on the field cycling history and the maximum field applied. When the field is nearly perpendicular to one of the branches, the FORC measurement reveals the magnetic interaction between the Dirac strings and orthogonal branches during the magnetization reversal process. Our results demonstrate that the FORC approach provides a comprehensive framework for understanding the magnetic interaction in the magnetization reversal processes of spin-frustrated systems. [ABSTRACT FROM AUTHOR]

The magnetoresistance (MR) of the single-crystalline Co/Pt(111) bilayers was studied systematically as a function of Co or Pt thickness at room temperature. For Co thickness dCo <6 nm, the resistances with in-plane magnetization M parallel (R∥) and transverse (R⊥) to current and with a perpendicular M normal (RP) to film show the unconventional behavior of RP > R∥ > R⊥. This MR behavior can be attributed to the combination effect of spin Hall MR with RP ≈ R∥ > R⊥ and the geometrical size effect. In addition, the angular dependent magnetoresistance behavior of the (111)-oriented Co/Pt bilayer shows striking difference with that of the (001)-oriented Co/Pt bilayer. [ABSTRACT FROM AUTHOR]

The electronic and transport properties of CuInTe2 chalcopyrite are investigated using density functional calculations combined with Boltzmann theory. The band gap predicted from hybrid functional is 0.92 eV, which agrees well with experimental data and leads to relatively larger Seebeck coefficient compared with those of narrowgap thermoelectric materials. By fine tuning the carrier concentration, the electrical conductivity and power factor of the system can be significantly optimized. Together with the inherent low thermal conductivity, the ZT values of CuInTe2 compound can be enhanced to as high as 1.72 at 850 K, which is obviously larger than those measured experimentally and suggests there is still room to improve the thermoelectric performance of this chalcopyrite compound. [ABSTRACT FROM AUTHOR]

In contrast to the extensive study of domain reversal in ferromagnetic materials, the domain switching process in antiferromagnets is much less studied due to the difficulty of probing antiferromagnetic spins. Using a combination of hysteresis loop, Kerr microscope, and x-ray magnetic linear dichroism measurements, we investigated the antiferromagnetic (AFM) domain switching process in single crystalline Fe/CoO bilayers on MgO(001). We demonstrate that the CoO AFM switching is a Kolmogorov-Avrami process in which the thermal activation energy creates AFM domain nucleation centers which further expand by domain wall propagation. From the temperature and thickness-dependent measurements, we are able to retrieve quantitatively the important parameter of the CoO AFM activation energy, which is shown to increase linearly with CoO thickness. [ABSTRACT FROM AUTHOR]

The isothermal oxidation behaviours of Al2TiO5/TiO2/ZrO2 composite coating on titanium alloy (TC4) deposited by micro-arc oxidation technique were studied at different temperature points of 1073, 1173 and 1273 K in dry air. The surface morphology and phase composition of all coated samples were investigated before and after oxidation by SEM and XRD, respectively. The weight gaining curves of the coated samples were plotted and the high temperature oxidation rates were evaluated, showing that the oxidation kinetics followed the parabolic rate law. And with increasing oxidation temperature, their oxidation rates also increased. The original phases of Al2TiO5/TiO2/ZrO2 coating on TC4 alloy consisted mostly of Al2TiO5 and R-TiO2 intermixed with small amounts of ZrO2 and the phased changed into mainly of R-TiO2, Al2O3 and little Al2TiO5 when after 1273 K oxidation for 1 h, whose average parabolic rate constant was 6.43 × 10−13 g2 cm−4 s−1, greatly lower than that of blank samples, 6.01 × 10−12 g2 cm−4 s−1, indicative of a good oxidation resistance for the Al2TiO5/TiO2/ZrO2 composite coating on TC4 surface. [ABSTRACT FROM AUTHOR]

Step-induced antiferromagnetic (AFM) uniaxial anisotropy and its effects on the exchange coupling have been systematically investigated in the epitaxial Fe/CoO bilayers on a MgO(OOl) vicinal surface. X-ray magnetic linear dichroism measurements proved that the atomic steps induced a strong in-plane AFM uniaxial anisotropy in the Coofilm. We found that the thermal activation induced in-plane 90° switching of CoO AFM in-plane spins. The competition among the step-induced AFM anisotropy, the interface exchange coupling, and thermal activation generate a novel multiple in-plane spin reorientation transition of the Fe magnetization, which can further provide new insights on the exchange coupling in FM/AFM systems. [ABSTRACT FROM AUTHOR]

Ion beam synthesized Ge nanoparticles in SiO2 film have received intense interest due to their distinctive optical features. Nevertheless, the fundamental mechanism behind luminescence from Ge nanoparticles still remains under debate. In order to investigate the influence of oxygen content on the optical properties of Ge nanoparticles, post-annealing treatments under various annealing atmospheres including vacuum, air, and N2 were conducted to synthesize Ge nanoparticles. An oxygen-free Si3N4 matrix material was also adopted to compare with the results of SiO2 one. The results revealed that photoluminescence (PL) around 3.1 eV can be emitted from Ge-implanted SiO2 films. However, Ge-implanted SiO2 films appear remarkably diverse PL characteristics when annealed in different ambient gases. PL intensity fluctuates with temperature in the specimens annealed under vacuum and air due to the GeOx formation and dissolution. Otherwise, the N2-annealed specimens can suppress germanium oxidation process, thus allowing for an entirely different evolution of PL intensity with temperature. In contrast to the SiO2 matrix, no PL emission can be found for the Ge nanoparticles formed in the Si3N4 films, again proving that the 3.1-eV emission band indeed originates from the oxygen-deficient centers at the interface between SiO2 matrix and Ge or GeOx nanoparticles. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The anisotropic magnetoresistance (AMR) in epitaxial Pt/Fe/MgO(001) bilayers was systematically studied as a function of Pt thickness, and a strong enhancement of AMR by the Pt layer was observed. The enhancement of AMR persists with a 1 nm Au layer inserted between Pt and Fe but disappears with a 1 nm MgO inserted layer. Both the spin Hall magnetoresistance theory and induced Pt moments located at the Fe/Pt interface cannot explain the observed AMR enhancement. The enhanced AMR in the Pt/Fe bilayer can be attributed to the Pt magnetic moment in the conduction band induced by the spin-polarized conduction electron, which has a long decay length of 1.7-2.6 nm. [ABSTRACT FROM AUTHOR]

In this work, the electronic properties of phosphorene nanoribbons with different width and edge configurations are studied by using density functional theory. It is found that the armchair phosphorene nanoribbons are semiconducting while the zigzag nanoribbons are metallic. The band gaps of armchair nanoribbons decrease monotonically with increasing ribbon width. By passivating the edge phosphorus atoms with hydrogen, the zigzag series also become semiconducting, while the armchair series exhibit a larger band gap than their pristine counterpart. The electronic transport properties of these phosphorene nanoribbons are then investigated using Boltzmann theory and relaxation time approximation. We find that all the semiconducting nanoribbons exhibit very large values of Seebeck coefficient and can be further enhanced by hydrogen passivation at the edge. Taking pristine armchair nanoribbons and hydrogen-passivated zigzag naoribbons with width N=7, 8, 9 as examples, we calculate the lattice thermal conductivity with the help of phonon Boltzmann transport equation and evaluate the width-dependent thermoelectric performance. Due to significantly enhanced Seebeck coefficient and decreased thermal conductivity, we find that at least one type of phosphorene nanoribbons can be optimized to exhibit very high figure of merit (ZT values) at room temperature, which suggests their appealing thermoelectric applications. [ABSTRACT FROM AUTHOR]

We present a theoretical study of the structural, electronic, and transport properties of bulk Bi2Te3 within density functional theory taking into account the van der Waals interactions (vdW) and the quasiparticle self-energy corrections. It is found that the optB86b-vdW functional can well reproduce the experimental lattice constants and interlayer distances for Bi2Te3. Based on the fully optimized structure, the band structure of Bi2Te3 is obtained from first-principles calculations with the GW approximation and the Wannier function interpolation method. The global band extrema are found to be off the high-symmetry lines, and the real energy band calculated is in good agreement with that measured experimentally. In combination with the Boltzmann theory, the GW calculations also give accurate prediction of the transport properties, and the calculated thermoelectric coefficients of Bi2Te3 almost coincide with the experimental data. [ABSTRACT FROM AUTHOR]

The magnetic properties of antiferromagnetic (AFM) spins were investigated using x-ray magnetic linear dichroism (XMLD) in epitaxial NiO/CoO/MgO(001) films as a function of film thickness, temperature, and interface modulation. We found that the NiO AFM spins undergo a spin reorientation transition (SRT) from the in-plane orientation to the out-of-plane orientation at a critical NiO thickness. The NiO AFM SRT can be attributed to the competition between the out-of-plane anisotropy of the NiO AFM spins and the AFM interfacial exchange coupling with the CoO in-plane spins. The NiO SRT thickness increases with the CoO thickness and also with the interfacial coupling strength. The temperature-dependent XMLD measurement indicates that the exchange coupling at the NiO/CoO interface can greatly enhance the Néel temperature of the CoO layer. [ABSTRACT FROM AUTHOR]

Objective: Guidelines on oxygenation policies and on the prevention and treatment of retinopathy of prematurity (ROP) were issued by the Chinese Medical Association in 2004. This study was undertaken to determine the incidence of and risk factors for ROP among preterm infants in Beijing, the capital of China, after implementation of the guidelines. Methods: Neonates with birth weights (BW) ~ 2000 g or gestationat age (GA) ~ 34 weeks admitted to the six largest neonatal intensive care units in Beijing during 2005 were enrolled. Ophthalmological examinations started 3- 4 weeks after birth, and ROP was classified using the revised International Classification. Maternal and perinatal risk factors for type 1 ROP were analysed. Results: Retinopathy of prematurity was detected in 10.8% of 639 neonates who had complete eye examinations, 23 of whom (3.6%) developed type 1 ROP and were treated. The rate of ROP needing treatment has not declined since 2002. Logistic regression analysis indicated that low BW, apnoea >20 s, anaemia, hypoxicischaemic encephalopathy and placenta abruption were significantly associated with type 1 ROP. Conclusion: In Beijing, rates of ROP needing treatment are high, and affected babies are more mature than in NICUs in high-income countries. More needs to be done to prevent ROP through improved neonatal care. [ABSTRACT FROM AUTHOR]

The spin relaxation process of acceptor-bound excitons in wurtzite GaN is observed by spin-dependent pump and probe reflectance measurement with subpicosecond time resolution. The time evolutions measured at 15–50 K have a single exponential component corresponding to the electron spin relaxation time of 1.40–1.14 ps. The spin relaxation time is found to be proportional to T-0.175, where T is the temperature. This weak temperature dependence indicates that the main spin relaxation mechanism is the Bir-Aronov-Pikus process [Sov. Phys. JETP 42, 705 (1976)]. [ABSTRACT FROM AUTHOR]

This letter reports on the investigation of p+–n junction variation produced by various annealing sequences. With well-controlled photoperturbation, we have employed scanning capacitance microscopy to directly observe the junction narrowing induced by post-spike furnace annealing. For p+–n junctions, it is revealed that post-spike furnace annealing may degrade the electrical activation of boron atoms, leading to junction narrowing without significant boron diffusion. The mechanism and the stability of electrical junctions formed by spike annealing are also discussed. The experimental results also clearly show that furnace annealing followed by spike annealing can result in junction broadening with a more concentrated boron profile. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have grown blue (480 nm) nitride semiconductor light emitting diodes (LEDs) by plasma-assisted molecular beam epitaxy (MBE) on GaN templates. Packaged devices exhibited output powers up to 0.87 mW at 20 mA forward current. The corresponding external quantum efficiency was 1.68%. Utilizing a combination of direct current (dc) and pulsed electroluminescence measurements it has been demonstrated that at low (<20 mA) dc conditions the emission from these devices is governed by the combined effects of bandfilling and screening of electrostatic fields. However, at larger currents device heating dominates the emission properties. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Using scanning capacitance microscopy (SCM), we have studied the photovoltaic effect on differential capacitance (dC/dV) signals of low-energy-BF[sub 2][sup +]-implanted silicon wafers. The surface photovoltage induced by the stray light of the atomic force microscope laser beam leads to distorted dC/dV profiles and hence perturbs the contrast of SCM images. Due to the photovoltaic effect on the junction region, the observed junction image also exhibits a narrower junction width. According to this study, the photovoltaic effect not only significantly affects the dC/dV signals but also deteriorates the accuracy of junction characterization, in particular for ultrashallow junctions and lower band-gap semiconductors. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The in-plane magnetic anisotropy in the Fe/MgO/GaAs(001) system has been carefully studied as a function of MgO thickness. The epitaxial relation is Fe(001)[110]//MgO(001)[100]//GaAs(001) [100] for dMgO >1 monolayer (ML). The interfacial uniaxial anisotropy was greatly reduced by the MgO interlayer, and the easy axis of the fourfold anisotropy was found to rotate from the GaAs<100> direction to the GaAs<110> direction. Such anisotropy transition happens within the 1.2 ML MgO thickness range. [ABSTRACT FROM AUTHOR]

An erratum is given on the article "Phosphorene nanoribbon as a promising candidate for thermoelectric applications", mentioning corrections for typographical errors in the original.