The Effect of Sowing Date and Autumn Management on Sainfoin \u3cem\u3e(Onobrychis viciifolia)\u3c/em\u3e Regrowth and Yield

Due to its characteristics (palatability, non-bloating, high protein, high voluntary intake etc.: Frame, 1998), sainfoin was a traditional forage legume in the UK, grown widely during the 17-19th century (Bland, 1971). It has almost disappeared in recent years. The rise of organic farming and the need for home-grown protein may encourage the return of sainfoin. This experiment aimed to explore the impact of sowing date and autumn management on the growth and yield of sainfoin in UK

Microscopic Modeling of the Growth of Order in an Alloy: Nucleated and Continuous Ordering

We study the early-stages of ordering in $Cu_3 Au$ using a model Hamiltonian derived from the effective medium theory of cohesion in metals: an approach providing a microscopic description of interatomic interactions in alloys. Our simulations show a crossover from a nucleated growth regime to a region where the ordering does not follow any simple growth laws. This mirrors the experimental observations in $Cu_3 Au$. The kinetics of growth, obtained from the simulations, is in semi-quantitative agreement with experiments. The real-space structures observed in our simulations offer some insight into the nature of early-stage kineticsComment: 13 pages, Revtex, 3 postscript figures in a second file

Quantum spin Hall effect and spin-charge separation in a kagome lattice

A two-dimensional kagome lattice is theoretically investigated within a simple tight-binding model, which includes the nearest neighbor hopping term and the intrinsic spin-orbit interaction between the next nearest neighbors. By using the topological winding properties of the spin-edge states on the complex-energy Riemann surface, the spin Hall conductance is obtained to be quantized as $-e/2\pi$ ($e/2\pi$) in insulating phases. This result keeps consistent with the numerical linear-response calculation and the \textbf{Z}$_{2}$ topological invariance analysis. When the sample boundaries are connected in twist, by which two defects with $\pi$ flux are introduced, we obtain the spin-charge separated solitons at 1/3 (or 2/3) filling.Comment: 13 NJP pages, 7 figure

Observation of discrete vortex solitons in optically-induced photonic lattices

We report on the frst experimental observation of discrete vortex solitons in two-dimensional optically-induced photonic lattices. We demonstrate strong stabilization of an optical vortex by the lattice in a self-focusing nonlinear medium and study the generation of the discrete vortices from a broad class of singular beams.Comment: 4pages, 5 colour figures. to appear in PR

The magnetocaloric effect and critical behavior in amorphous Gd 60Co 40-xMn x alloys.

The amorphous alloys Gd60Co40−xMnx (x = 0, 5, 10, 15) were prepared by melt spinning. The Curie temperature,T c, increases monotonously with Mn addition, ranging from 198 K for x = 0 to 205 K for x = 15, while the maximum values of −ΔSM under the applied field change from 0 to 5 T are 7.7, 7.1, 6.2 and 5.4 J·kg−1·K−1 for x = 0, 5, 10, and 15, respectively. All samples undergo a second order ferri-paramagnetic phase transition. The critical behavior around the transitiontemperature is investigated in detail, using both the standard Kouvel-Fisher procedure as well as the study of the field dependence of the magnetocaloric effect. Results indicate that the obtained critical exponents are reliable, and that the present alloys exhibit local magnetic interaction

Magnetic properties and magnetocaloric effects in GdCo9Si2 compound with multiple magnetic phase transitions

The structure and magnetic properties of polycrystalline GdCo9Si2 compound have been investigated. It has a BaCd11 structure and undergoes two magnetic phase transitions: an antiferromagnetic to ferrimagnetic transition occurring at rv93 K, and a ferrimagnetic to paramagnetic transition at 420 K, which results in a positive and a negative magnetic entropy change, respectively. The two peak values of magnetic entropy change are -0.6 and 1.1 J·kg-1 K-1 for DH ¼ 5 T. Furthermore, there exists a metal-semiconductor transition temperature (TP), below which the resistance increases with increasing temperature, while the semiconductor characteristic is observed above TP. The magnetic domain structures are characterized by stripe and grid structures 1 lm wide. Although the MCE is small for applications, its study is useful to clearly understand the nature of multiple magnetic phase transitions in the GdCo9Si2 compound

MedZIM: Mediation analysis for Zero-Inflated Mediators with applications to microbiome data

The human microbiome can contribute to the pathogenesis of many complex diseases such as cancer and Alzheimer's disease by mediating disease-leading causal pathways. However, standard mediation analysis is not adequate in the context of microbiome data due to the excessive number of zero values in the data. Zero-valued sequencing reads, commonly observed in microbiome studies, arise for technical and/or biological reasons. Mediation analysis approaches for analyzing zero-inflated mediators are still lacking largely because of challenges raised by the zero-inflated data structure: (a) disentangling the mediation effect induced by the point mass at zero; and (b) identifying the observed zero-valued data points that are actually not zero (i.e., false zeros). We develop a novel mediation analysis method under the potential-outcomes framework to fill this gap. We show that the mediation effect of the microbiome can be decomposed into two components that are inherent to the two-part nature of zero-inflated distributions. The first component corresponds to the mediation effect attributable to a unit-change over the positive relative abundance and the second component corresponds to the mediation effect attributable to discrete binary change of the mediator from zero to a non-zero state. With probabilistic models to account for observing zeros, we also address the challenge with false zeros. A comprehensive simulation study and the applications in two real microbiome studies demonstrate that our approach outperforms existing mediation analysis approaches.Comment: Corresponding: Zhigang L

Low hysteresis and large room temperature magnetocaloric effect of Gd 5Si2.05-xGe1.95-xNi2x (2x 0.08, 0.1) alloys

Gd5Si2.05-xGe1.95-xNi2x (2x ¼ 0.08, 0.1) alloys were prepared by arc melting followed by annealing at 1273 K for 96 h. Mixed monoclinic Gd5Si2Ge2-type phase, orthorhombic Gd5Si4-type phase, and a small amount of Gd5Si3-type phase were obtained in these alloys. Gd5Si2.01Ge1.91Ni0.08 alloy undergoes a second-order transition (TC) around 300 K, whereas Gd5Si2Ge1.9Ni0.1 alloy exhibits two II I transitions including a first-order transition (TC ) at rv295 K and second-order transition (TC ) at rv301 K. Ni substitution can effectively reduce the thermal hysteresis and magnetic hysteresis while max maintaining large magnetic entropy change. The maximum magnetic entropy changes (|DSM |) of 1 -1 Gd5Si2.05-xGe1.95-xNi2x alloys with 2x ¼ 0.08 and 0.1 are 4.4 and 5.0 J kg- K, respectively, for 0–2 T, and are 8.0 and 9.1 J kg-1 K-1, respectively, for 0–5 T. Low hysteresis performance and relatively large magnetic entropy change make these alloys favorable for magnetic refrigeration applications

Comparing the Weighted Density Approximation with the LDA and GGA for Ground State Properties of Ferroelectric Perovskites

First-principles calculations within the weighted density approximation (WDA) were performed for ground state properties of ferroelectric perovskites PbTiO$_3$, BaTiO$_3$, SrTiO$_3$, KNbO$_3$ and KTaO$_3$. We used the plane-wave pseudopotential method, a pair distribution function $G$ based on the uniform electron gas, and shell partitioning. Comparing with the local density approximation (LDA) and the general gradient approximation (GGA), we found that the WDA significantly improves the equilibrium volume of these materials in cubic symmetry over both the LDA and GGA; Ferroelectric instabilities calculated by the WDA agree with the LDA and GGA very well; At the experimental ferroelectric lattice, optimized atom positions by the WDA are in good agreement with measured data; However the WDA overestimates the strain of tetragonal PbTiO$_3$ at experimental volume; The WDA overestimates the volume of fully relaxed structures, but the GGA results are even worse. Some calculations were also done with other models for $G$. It is found that a $G$ with longer range behavior yields improved relaxed structures. Possible avenues for improving the WDA are discussed.Comment: 19 pages, 3 figures, submitted to PR