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Several zirconium isotopes are in the path of slow neutron capture (s) process, and the direct components of (n,γ) reactions can be derived from their neutron spectroscopic factors. In the present work, the angular distributions of (12C,13C) and (13C,12C) reactions on targets 90,92,94,96Zr were obtained using the high-precision Q3D magnetic spectrograph at the Beijing HI-13 tandem accelerator in China Institute of Atomic Energy. The distorted-wave Born approximation calculations were performed to extract the spectroscopic factors, using three different sets of Woods-Saxon potential parameters for these heavy-ion systems. The neutron spectroscopic factors for the ground state of 90-97Zr have been obtained and compared with other experimental data. [ABSTRACT FROM AUTHOR]

The spin-induced electric polarization in multiferroics with long-period modulated magnetic structure and some polar crystals is difficult to calculate directly due to the modeling limitation or the lack of a reference paraelectric phase. We propose a general method to investigate spin-induced polarization by combining symmetry arguments and first-principles calculations, and demonstrate it in the triangular-lattice delafossite structure. Two special spin models based on the four-sublattice orthorhombic supercell were used to calculate the polarization induced by spin-current and p-d hybridization mechanisms, respectively. All the polarization components appearing in various spiral spin orders can be explained by the two different spin-current mechanisms through analyzing the symmetry of S a × S b vectors, where S a and S b represents the neighbor spins. We confirm that the p-d hybridization mechanism only plays a minor role in the origins of polarization in addition to causing the 2 q lattice modulation, where q is the magnetic modulation wave number. [ABSTRACT FROM AUTHOR]

The magnetic anisotropy, exchange couplings, and spin-driven ferroelectricity in recently discovered multiferroic oxide α - Cu2V2O7 have been investigated using first-principles calculation and symmetry analysis. Density functional theory (DFT) calculations predict easy a -axis anisotropy, while applying an on-site Hubbard correction (DFT + U) converts the easy axis into b direction. These results can explain the discrepancy of easy axis between previous theoretical prediction and experimental results. The third-nearest-neighbor exchange interaction is proved to be dominant for the antiferromagnetic structure. The nearest-neighbor Dzyaloshinskii-Moriya interaction plays an important role in the origins of spin canting, and the canted magnetic moments are oriented predominantly along the c axis. Although the spin-dependent p - d hybridization mechanism induces a sizable electric polarization, the observed large polarization can be mainly attributed to the exchange-striction mechanism including spin-lattice coupling. [ABSTRACT FROM AUTHOR]

We show that a high-energy electron bunch can be used to capture the instantaneous longitudinal and transverse field structures of the highly transient, microscopic, laser-excited relativistic wake with femtosecond resolution. The spatiotemporal evolution of wakefields in a plasma density up ramp is measured and the reversal of the plasma wake, where the wake wavelength at a particular point in space increases until the wake disappears completely only to reappear at a later time but propagating in the opposite direction, is observed for the first time by using this new technique. [ABSTRACT FROM AUTHOR]

The article presents abstracts of several research papers on inguinal hernia including retromuscular repair with and without posterior component separation in flank hernias, laparoscopic ventral or incisional hernia repair and laparoscopic management of lumbar hernias. [ABSTRACT FROM AUTHOR]

The relative γ-decay probability ratios of the neutron resonance states in 94Zr and 92Zr populated via two-neutron transfer reactions, 92Zr(18O,16O)94Zr and 90Zr(18O,16O)92Zr, have been measured to test the validity of the surrogate ratio method (SRM) in determining the (n, γ) reaction cross section. The cross sections of the 93Zr(n,γ)94Zr reaction are derived from the experimentally obtained ratios and the cross sections of the 91Zr(n,γ)92Zr reaction in the equivalent neutron energy range of En=0-8MeV. The deduced cross sections of 93Zr(n,γ)94Zr reaction agree with the directly measured ones in the low-energy region, and with the evaluated ENDF/B-VII.1 data at higher energies of En>3MeV. The agreement supports the concept of the SRM method to indirectly determine the (n,γ) reaction cross sections. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Native envelope-based immunogens derived from critical timepoints in the development of breadth elicit rapid neutralizing antibodies in rabbits," by D. C. Malherbe and colleagues is presented.

The article discusses the study on the relative effectiveness of clinic and home blood pressure monitoring compared with ambulatory blood pressure monitoring for hypertension. It states that more widespread use of ambulatory blood pressure for the diagnosis of hypertension results in more appropriately targeted treatment. It mentions that the paucity of data particularly for home monitoring means the results should be interpreted with caution due to the lack of consensus internationally.

Abstract: Systematic studies of nuclear astrophysical reactions induced by lithium isotopes using the unstable ion beam facility GIRAFFE in CIAE were performed. We have measured the angular distributions of some single nucleon transfer reactions, such as 8Li(d,p)9Li, 8Li(d,n)9Be and 8Li(p,d)7Li in inverse kinematics, and derived the astrophysical S-factors or reaction rates for 8Li(n,γ)9Li and 8Li(p,γ)9Be by using asymptotic normalization coefficient (ANC) or spectroscopic factor. [Copyright &y& Elsevier]

Abstract: The elastic resonance scattering of and has been studied in inverse kinematics via a thick-target method. The excitation function for the scattering was obtained in the energy interval of with a secondary beam of . The resonance parameters for five low-lying levels in were deduced by R-matrix fitting calculations. In the case of scattering, preliminary result on the experimental excitation function is presented, in which the 4.52 MeV 3+ and 5.11 MeV 2+ states in are clearly discernable. [Copyright &y& Elsevier]

Various devices can be realized on strained GeSi/Si substrates by doping the substrate with different impurities such as As. As is an n-type dopant in both Ge and Si. As cross contamination can also arise during germanium preamorphization implantation due to inadequate mass resolution in the implanter. Thus, it is important to be able to accurately measure low-level As concentrations in the presence of Ge. Secondary ion mass spectrometry (SIMS) is the standard technique for these types of measurements but is constrained by mass interferences from molecular ions ([sup 74]GeH, [sup 29]Si[sup 30]Si[sup 16]O). The trace element accelerator mass accelerator technique allows the breakup of interfering molecules. As is measured in a GeSi matrix with sensitivity significantly better than SIMS. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]