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Abstract: Food quality and availability are important factors influencing the survival and reproduction of animals. The aim of the present study was to examine the effect of dietary fiber content [...]

The safety of mooring systems on offshore platforms seems more and more significant with the utilization of offshore space and resources, so the reduction of wave drift force is the key issue in this wave-body interaction problem. The wave drift force acting on the inner floating body surrounded by multiple small floating bodies can be reduced obviously with the occurrence of a phenomenon, which is called the Cloaking phenomenon. The Cloaking phenomenon refers to the reduction or complete elimination in amplitude of the scattered waves. In this paper, a real-coded genetic algorithm was used to optimize the parameters of outer floating bodies to minimize the scattered wave energy, and then the wave drift force acting on the inner body can be reduced. Furthermore, associated CFD simulations and experimental research were conducted with the above optimized parameters to investigate and verify the Cloaking phenomenon more systemically. It is shown that the wave drift force acting on the inner floating body in the Cloaking configuration can be reduced obviously both in numerical and experimental research, and the reduction of the wave drift force is closely related to the change of wave field around the structure.

We present the micromagnetic study of magnonic band structures for exchange spin waves propagating in one-dimensional magnonic crystals. The crystals are of laterally patterned periodic arrays of alternating cobalt and nickel stripes. Large magnonic bandgaps with widths of tens of GHz are observed. It is found that the higher-order transmission bands and bandgaps have wider widths than those of the lower-order bands and bandgaps. Another interesting feature is that the widths of the first two bandgaps are independent of the applied field, in contrast with an earlier report of decreasing bandgap widths with increasing applied field observed for dipolar spin waves. [ABSTRACT FROM AUTHOR]

An investigation of the interfacial magnetization dynamics of a magnonic crystal comprising alternating, contacting cobalt and Permalloy nanostripes is reported. Recently measured spin-wave dispersion data of the crystal in its ferromagnetic and antiferromagnetic phases are interpreted in terms of the effective spin pinning at its cobalt-Permalloy interfaces based on generalized Guslienko-Slavin boundary conditions. Calculations using a macroscopic theory well reproduce the experimental data. Numerically generated mode profiles reveal considerable effective pinnings at the interfaces. The obtained pinning parameters have values significantly larger than the values calculated at the lateral edges of individual stripes, suggesting that the strong interfacial coupling, reported in our previous study, contributes significantly to the effective pinning at the interfaces between adjacent stripes. [ABSTRACT FROM AUTHOR]

Brillouin measurements have been carried out on a low density array of 20 nm thick Ni80Fe20 equilateral triangles with an edge length of 190 nm, under an in-plane magnetic field applied perpendicular to one edge of the triangular magnets. The dynamical matrix method is employed to identify the observed spin wave modes. Most of the observed modes can be classified into different categories based on their mode profiles, with modes in each category characterized by the same number of nodal lines along the direction of the applied field but having different spatial localization. Hybrid modes with different numbers of nodal lines in different regions of the nanomagnet are also found to exist. The spatial localization and the spatial variation in the spin wave character for the observed modes have been calculated based on the spin wave well model. Calculations based on the simple model give reasonable agreement with numerical results obtained by the dynamical matrix method. [ABSTRACT FROM AUTHOR]

The field-orientation dependence of magnetization reversal and spin wave modes in nanorings has been investigated by focused magneto-optical Kerr effect spectroscopy, Brillouin spectroscopy, and micromagnetic simulations. The samples studied are periodic arrays of 150 nm wide Ni80Fe20 rings with long axes of 850, 1200, and 1500 nm, and respective short axes of 550, 700, and 900 nm. For the smallest ring, the onion-to-vortex transition is observed for both the applied magnetic field directed along, and 5° from its magnetization easy axis. In contrast for the two larger rings, this transition is not observed for the field in the latter orientation. Splitting of spin wave modes is observed for the transition from the onion to vortex state. Micromagnetic simulations of magnetization reversal and spin waves are in good agreement with experiments. The simulated temporal recording of magnetization distributions during transition reveals that different switching mechanisms result from different applied magnetic field orientations. [ABSTRACT FROM AUTHOR]

The advantages of a non-equatorial space elevator have attracted the attention of several researchers. In this paper, two static tether models are presented for studying the tapering of a uniform-stress tether using a discretization method. The efficiency and accuracy of the two models are verified by comparing them with models used in other studies. We then study the range of latitudes that allowed for a uniform-stress space elevator and evaluate the influence of the anchor-point latitude on the system payload capacity. The results show that increasing the tensile strength of the tether material can expand the range of the space elevator system deployment. However, a high latitude of anchorage would greatly sacrifice the payload capacity. [ABSTRACT FROM AUTHOR]

Chemical communication plays an important role in reproductive and social behaviour of small mammals. The chemical constituents of urine were the main signal resources that can encode sex and social status. The purpose of the present study was to test volatile chemical substances in urine of the kinship and non-kinship Tupaia belangeri, volatile chemicals in urine were performed by the gas chromatography and mass spectrometry (GC-MS), which is speculated that volatile chemicals in urine may had key role in its kin recognition of T. belangeri. The results showed that the components of volatile chemicals in urine were similar between the kinship and non-kinship T. belangeri, which the main components were Alcohols, Alkanes, Esters and Ketones, but the types of each materials were discrepant. “Formic acid, octyl ester” were absence or existence regularly, and “α-Farnesene” and “2,4-Dithiapentane” were found in kinship and non-kinship T. belangeri, which may be signaling substances in the urine. All of the results suggested that volatile chemical substances in urine were different in kinship and non-kinship T. belangeri, indicating that chemical communication based on signals in urine plays an important role in its kin recognition of T. belangeri. [ABSTRACT FROM AUTHOR]