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Searching for low-power-consuming and high-efficient methods for well controllable driving of skyrmion motion is one of the most concerned issues for future spintronic applications, raising high concern with an appreciated choice of magnetic media and driving scenario. In this work, we propose a novel scenario of spin wave driven skyrmion motion in a ferrimagnetic (FiM) lattice with the net angular momentum {\delta}s. We investigate theoretically the effect of both {\delta}s and the circular polarization of spin wave on the skyrmion dynamics. It is revealed that the momentum onto the skyrmion imposed by the excited spin wave can be partitioned into a ferromagnetic term plus an antiferromagnetic term. The ratio of these two terms and consequently the Hall angle of skyrmion motion can be formulated as the functions of {\delta}s, demonstrating the key role of {\delta}s as an effective control-parameter for the skyrmion motion. Moreover, the spin wave frequency dependent skyrmion motion is discussed, predicting the frequency enhanced skyrmion Hall motion. This work thus represents an essential contribution to understand the skyrmion dynamics in a FiM lattice., Comment: 25 pages, 4 figures

Magnetic skyrmions are magnetic textures with topological protection, which are expected to be information carriers in future spintronic devices. In this work, we propose a scheme to implement hybrid magnetic skyrmions (HMS) in ferrimagnets, and we study theoretically and numerically the dynamics of the HMS driven by spin-orbit torque. It is revealed that the skyrmion Hall effect depends on the skyrmion helicity and the net angular momentum ({\delta}s), allowing the effective modulation of the HMS motion through tuning Dzyaloshinskii-Moriya interaction and {\delta}s. Thus, the Hall effect can be suppressed through selecting suitable materials to better control the HMS motion. Moreover, Magnus force for finite {\delta}s suppresses the transverse motion and enhances the longitudinal propagation, resulting in the HMS dynamics in ferrimagnets faster than that in antiferromagnets., Comment: 25 pages, 6figures

Stray laser light is a serious problem that interrupts the measurement of electron temperature and density in Thomson scattering (TS) systems. This paper presents a ray-tracing simulation of stray laser light in HL-2M TS systems. A model including (i) a simplified laser-beam injection system, (ii) the scattered-light collection systems for central-point TS (CPTS) and edge TS (ETS), and (iii) the HL-2M vessel is built using the TracePro and CATIA software packages based on measurements of the bidirectional scattering distribution function at a wavelength of 532 nm. The simulation results show that no stray laser light reaches the injection surface of the collection lens of the CPTS system, and only a few stray laser rays of all the rays reaching the injection surface of the collection lens of the ETS system can be collected when the energy threshold per ray is 1 × 10−16. The stray laser rays that reach the scattered-light collection systems are mainly from the first and second parts of the slides of the beam dump, so decreasing the roughness of those parts could be effective in reducing the level of stray laser light.

Some progress has been made to develop the multipoint Thomson scattering (TS) diagnostic for the HL-2A tokamak physics experiments. Hardware of silicon avalanche photodiode detector electronics is improved, which provides two output signal channels. In one channel, only the rapid TS signal is the output after deducting the influence of the background slow-varying plasma light. In the other, both the rapid TS signal and the plasma background signal are the output. In the latest HL-2A experiment campaign, the newly developed electronics are tested and TS signals can be obtained from each of the two channels, where the signal is digitized by 12-bit transient recorder sampled at 1 GS/s. Laser beam alignment is fulfilled by using motorized stages to control the laser beam passing through ∼10 mm-wide narrow throats of the lower and upper closed divertors with small movements and then the stray laser light is reduced. New modules of fast digitizers with more than 100 channels are installed and will be used to record TS pulse signals. On the basis of these achievements, about 15-point measurements of plasma electron temperature and density by Thomson scattering diagnostic will come into operation in the upcoming HL-2A experiment campaign.

The edge tangential Thomson scattering system (ETTSS) was developed for the first time on a HL-2A tokamak. A Nd:YAG laser with a 1064 nm wavelength, 4 J energy, and 30 Hz repetition rate is employed on the ETTSS. The laser beam injects the plasma in the tangential direction on the mid-plane of the machine, and the angles between the laser injection direction and the scattered light collection direction are in the range from 157.5° to 162.8°. The scattered light collection optics with 0.21-0.47 magnification is utilized to collect the scattered light of measurement range from R = 1900 mm to 2100 mm (the normalized radius is from r/a = 0.625 to 1.125). Spatial resolution of the preliminary design could be up to Δr/a = 0.016. The measurement requirements could be achieved: 10 eV < Te < 1.5 keV, and 0.5 × 1019 m−3 < ne < 3 × 1019 m−3 with errors less than 15% and 10%, respectively.

We report experimental observation of large anomalous Hall effect exhibited in non-collinear triangular antiferromagnet D019-type Mn3Ga with coplanar spin structure at temperatures higher than 100 K. The value of anomalous Hall resistivity increases with increasing temperature, which reaches 1.25 μΩ · cm at a low field of ~300 Oe at room temperature. The corresponding room-temperature anomalous Hall conductivity is about 17 (Ω · cm)−1. Most interestingly, as temperature falls below 100 K, a temperature-independent topological-like Hall effect was observed. The maximum peak value of topological Hall resistivity is about 0.255 μΩ · cm. The appearance of the topological Hall effect is attributed to the change of spin texture as a result of weak structural distortion from hexagonal to orthorhombic symmetry in Mn3Ga. Present study suggests that Mn3Ga shows promising possibility to be antiferromagnetic spintronics or topological Hall effect-based data storage devices.

SUMMARYThe present study was conducted to determine the effects of a polysaccharide of Atractylodes macrophala Koidz (PAM) as a dietary additive on growth performance, immunoglobulin concentration and IL-1β expression in weaned piglets. One hundred and twenty Landrace×Yorkshire piglets weaned at 28 days old (body weight 7·5±0·07 kg) were assigned to five treatment groups (three pens/group, eight piglets/pen) fed maize/soybean-based diets supplemented with 0, 3, 6 or 9 g of PAM/kg diet or antibiotics (0·4 g flavomycin/kg+0·13 g olaquindox/kg). The experimental period was 28 days. With increasing PAM supplementation levels, average daily gain was greater (quadratic, PPPPP

This study was conducted to determine the effects of exogenous zinc-metallothionein (Zn-MT) on anti-oxidative function and pork quality. After feeding a corn-soybean meal-based diet for two weeks, 48 pigs (Duroc x Landrace x Chinese Black Pig) were assigned randomly to four groups. Pigs in Group 1 were maintained under non-stress conditions, whereas pigs in Groups 2, 3 and 4 were aggressively handled for 25 min to produce stress. Pigs in Groups 1, 2, 3, and 4 received intramuscular administration of saline (control group; CON), 0 (negative control group; NCON), 0.8 (low dose group; LOW), and 1.6 (high dose group; HIGH) mg rabbit liver Zn-MT per kg body weight, respectively. Pigs were slaughtered at 3 and 6 h post-injection. Zn-MT treatment increased (p

The experiment was conducted to assess the effects of phytase supplementation to diets with two levels of phosphorus (P) on ileal and faecal digestibility of nutrients and phosphorus, calcium, nitrogen and energy balances in growing pigs. Fifteen Landrace × Large White × Chinese Black barrows, with an initial live weight of 22·2 kg fitted with a simple T-cannula at the distal ileum, were randomly allocated to one of the five diet treatments, according to a of cross-over design with two periods. The basal diet was typical of southern Asia with maize/rice and rapeseed/cottonseed meals. A normal (NP, supplemented with 4·8 g/kg of CaHPO4) and a low-P diet (LP, not supplemented with CaHPO4) were formulated. Both of the diets were supplemented with and without Natuphos® Phytase (500 phytase units (FTU) per kg diet). An enzyme hydrolysed casein (EHC) diet (diet 5) was also formulated to determine the flow of the ileal endogenous amino acids (AA). The results showed that both the higher level P treatment and phytase supplementation increased (P < 0·05) the apparent ileal digestibility (AID) of dry matter (DM), organic matter (OM), crude protein (CP) and energy. Phytase supplementation also increased (P < 0·05) the AID of Ca and P. Pigs given the higher level of P or the phytase diet increased apparent faecal digestibility (AFD) of DM, OM and energy. Phytase supplementation reduced (P < 0·01) faecal Ca output and increased (P < 0·05) proportional Ca retention. The higher level of P increased (P < 0·001) total P intake and P retention (P < 0·05) but did not affect the proportion of P retained (P > 0·05). Phytase supplementation did not affect P balance (P > 0·05). Pigs given the higher level P or the phytase diet had reduced (P < 0·05) faecal energy concentration, although there was no affect on urine energy output, digestible energy (DE) and metabolizable energy (ME). However, there were P × phytase effects on DE and ME (P < 0·05). There were no P × phytase effects (P > 0·05) on AID of AA except with isoleucine (P < 0·01). Phytase supplementation increased (P < 0·05) AID of histidine, isoleucine, threonine and glutamine and there was a numeric increase in AID for most of the other AA. There was P × phytase effect on AFD of histidine (P < 0·05), isoleucine (P < 0·05), methionine (P < 0·05) and threonine (P < 0·01). Phytase supplementation increased the AFD of isoleucine (P < 0·05), threonine (P < 0·01) and tended to increase AFD of tyrosine (P < 0·05). The level of MCP affected the AFD of lysine (P < 0·01), threonine (P < 0·05), aspartic acid (P < 0·05). Phytase supplementation increased true ileal digestibility of histidine (P < 0·05), isoleucine (P < 0·001), threonine (P = 0·001), glutamine (P < 0·01), respectively. These results indicate that phytase used in the present study was able to improve the utilization of DM, OM, CP, Ca, P, energy and amino acid in a maize/rice and rapeseed/cottonseed meal based diet and reduce total output of them in manure.

The greatest progress in carbohydrate study in pig nutrition and health is that the carbohydrates are classifi ed more clearly not only based on their structure, but also on their nutritional functions. Carbohydrates serve as components of cell structures, energy substrate and have regulatory functions. There are large differences in the digestion, absorption and the speed of the carbohydrates appearance in the portal vein blood plasma. Non-starch polysaccharides (NSP) and particularly soluble one and resistant starch (RS) may have negative effects on dietary nutrient utilization in pig growth, however, some of the NSP and RS have health benefi ts.

Some efforts have been made to promote the performance of incoherent Thomson scattering (TS) diagnostic on HL-2A tokamak. Motorized stages are used to adjust the reflecting mirrors and focusing lens of the input laser beam optics, by which it is easy to control the laser beam pass through the narrow throats of the lower and upper closed divertors. Spectral calibration has been refined. Hardware of Si-APD detector electronics is improved, which provides two output signal channels. In one channel, only the rapid TS signal is output after deducting the influence of plasma light. In the other, both the rapid TS signal and the background signal of slow-varying plasma light are output. In this 2017 experiment campaign, the new developed electronics are tested and TS signals can be obtained from the two channels, which are digitized by 1GS-12bit transient recorders. In data processing, the TS pulse shape is fitted with different functions output from the two different channels. The statistical estimation of Te data is also optimized. More channels of high-speed digitizers and more positions of Te and ne measurement are planned and are in constructions.