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Muon spin rotation/relaxation/resonance (μSR) spectroscopy uses highly polarized muons to study the microscopic magnetic structure and dynamics of condensed matter. In addition to the five existing muon facilities, the first Chinese muon source, the Muon station for sciEnce technoLOgy and inDustrY (MELODY), is planned to be constructed in Phase II of the China Spallation Neutron Source (CSNS). It aims to provide intense and pulsed muon beams to conduct μSR applications in multiple disciplines. The group from the University of Science and Technology of China (USTC) participated in the collaboration with the CSNS accelerator group for the construction of the muon source. The USTC group led the research and development (R&D) of the first-generation photomultiplier tube (PMT)-based μSR spectrometer, and the design of the second-generation silicon photomultiplier (SiPM)-based spectrometer. The PMT-based spectrometer is a 128-channel prototype to demonstrate and develop key detector and electronics technologies for the planned MELODY. After several iterative designs and updates of detectors and electronics, the spectrometer prototype achieved a 7-ns dead time, which can record more than 12 positrons per channel per pulse according to the ISIS running experience. Based on the technologies developed from the first-generation spectrometer, the second-generation spectrometer will use SiPMs to accommodate over 2500 detector units to make better use of muons in MELODY. The two generation developments of Chinese μSR spectrometers will greatly advance the construction of MELODY, and provide high-quality data for users to interpret material properties in the near future.

Currently, antimicrobial peptides (AMPs) are of growing interest as potential substitutes for antibiotic growth promoters in animal production. The present study was conducted to evaluate the effects of dietary supplementation of bioengineering artificial Parasin I protein (API) and artificial plectasin protein (APL) (named as compound bioengineering protein, CBP) on growth performance and intestinal health of broilers. A total of 450 one-day-old Arbor Acres male healthy broilers were randomly allotted to 5 dietary groups with 10 replicates of 9 individuals in each replicate and supplemented with 0, 250, 500, 750, and 1,000 mg/kg CBP for 6 wk. Dietary CBP supplementation increased (P< 0.01) body weight (6 wk), average daily gain (0–6 wk), and average daily feed intake (3–6 wk and 0–6 wk). CBP addition enhanced antioxidant capacity, which was accompanied by the higher (P< 0.05) activity of serum total antioxidant capacity (T-AOC) (750 mg/kg), jejunal glutathione peroxidase (750 mg/kg), and T-AOC (500 and 1,000 mg/kg). Dietary CBP addition improved intestinal health, reflecting by the increased (P< 0.05) villus height to crypt depth ratio in the duodenum, the upregulated (P< 0.01) mRNA levels of claudin-1(500 and 750 mg/kg) in the ileum, the downregulated (P< 0.01) mRNA expression of occludin(500 mg/kg) in the duodenum and claudin-1(500 mg/kg) and occludin(500 and 750 mg/kg) in the jejunum, and the upregulated mRNA expression of (P< 0.01) mucin2 (MUC2) (1,000 mg/kg) in the duodenum. In addition, CBP upregulated (P< 0.01) IL-10(1,000 mg/kg) in duodenum and ileum, and downregulated (P< 0.05) the mRNA expression of IL-6(750 and 1,000 mg/kg), interferon-γ(1,000 mg/kg) in the jejunum and TNF-α(250 mg/kg) in the ileum. Furthermore, dietary CBP increased (P< 0.01) the abundance of total bacteria and Lactobacillus(500 and 750 mg/kg), and reduced (P< 0.05) the abundance of Escherichia coli(750 mg/kg) in the cecum. In conclusion, CBP supplementation enhances the antioxidant capacity, intestinal health, immune function, and ameliorates the gut microflora population, thus improving the growth performance of broilers. Dietary supplementation of 750 mg/kg CBP exhibits a better beneficial effect.

For 2519 aluminum alloy, there are very complex nonlinear relations among the thermal dynamical parameters in the process of deforming. In this paper, the support vector regression (SVR) approach is proposed to establish a model for predicting flow stress of 2519 alloy base on the flows tress experimental data of 2519 aluminum alloy under two influential factors, including strain and strain rate. Research showed that the prediction precision of SVR model is high enough: the mean absolute error (MAE) is 0.181, mean absolute percentage error (MAPE) is 0.434%, root mean square error (RMSE) is 0.22, multiple correlation coefficient (R2) is 0.998. This research suggests that SVR is an effective and powerful tool for predicting the flow stress of 2519 aluminum alloy.

The effects of tooth modification on the nonlinear dynamic behaviors are studied in this paper. Firstly, the static transmission error under load combined with misalignment error and modification are deduced. These effects can be introduced directly in the meshing stiffness and static transmission error models. Then the effect of two different type of tooth modification combined with misalignment error on the dynamic responses are investigated by using numerical simulation method. The numerical results show that the misalignment error has a significant effect on the static transmission error. The tooth crowning modification is generally preferred for absorbing the misalignment error by comparing with the tip and root relief. The tip and root relief can not resolve the vibration problem induced by misalignment error but the crowning modification can reduce the vibration significantly.

The amenability of limonite ore, the iron rich nickel laterite phase, was observed to be less than saprolite, the silicate rich phase, when subjected to biological leaching with heterotrophic microorganisms. To understand this difference, controlled leaching of the various nickel laterite minerals was conducted using citric acid to mimic the chemical action of the organisms and subsequent characterisation of the leached residues. The raw ore and the leached mineral residues were examined using high-resolution synchrotron based X-ray diffraction and optical microscopy. The possible contribution of electrosorption and solid porosity was also considered. The results suggest that although electrosorption contributes to nickel and cobalt losses, it is the structural changes induced by the acid in the minerals which effects the recovery of the metals. Citric acid was found to dehydroxylate saprolite minerals resulting in an unstable nickel oxide and thus making it susceptible to acid attack. This behaviour was not observed in the limonite ore, which was found to be poorly leached by citric acid.

Sequencing of oligodeoxynucleotide phosphorothioate by a modified Sanger method of sequencing is described. The procedure involves ligation of synthetic oligodeoxynucleotide phosphorothioate to an oligodeoxynucleotide, referred to here as "helper oligonucleotide." The helper oligonucleotide has a region which is complementary to T7 primer. By using DNA polymerase and nucleoside triphosphate mixture, 5′-labeled T7 primer is extended onto ligated oligodeoxynucleotide phosphorothioate, which is then analyzed on gel electrophoresis.

This study was conducted to evaluate the effect of supplementing hydroxy selenomethionine (OH-SeMet) on performance, selenium (Se) deposition in the breast muscle, quality and oxidative stability, and expression of selenoprotein encoding genes of breast meat of the native slow-growing yellow-feathered broiler birds. A total of 375 one-day-old local yellow male birds were randomly assigned into 5 dietary treatments, supplemented with Se 0.0, 0.2, 0.4, 0.6, and 0.8 mg/kg in the form of OH-SeMet. Each treatment consisted of 5 replicates and each replicate had 15 birds, the birds were fed on basal diet containing corn and soybean meal, and the experiment lasted for 63 d. The results showed that dietary Se supplementation linearly increased (P< 0.001) Se contents in both serum and muscle, no significant changes (P> 0.05) were observed on growth performance, yield of breast, meat color, and intramuscular fat deposition of the breast muscle. Dietary Se addition improved water-holding capacity, the pH24hvalue, and tenderness of breast muscle, evidenced by a linear decreases of shear force (P< 0.05), accompanied by lower thiobarbituric acid reactive substances and higher glutathione reductase activity. The mRNA abundance of selenoprotein encoding genes also responded to dietary Se levels. It is concluded that, dietary supplementation with OH-SeMet improved muscular Se deposition and meat quality of the native yellow birds, with enhanced antioxidant capability and regulation in selenogenome.

Calculations are reported showing that in multilayered heterojunction structures the effective impact ionisation rates for electrons and holes can be very different, even if they are the same in the basic bulk materials. The reason for this is the difference in the band-edge discontinuities for electrons and holes and the lower phonon mean free path for holes in quantum well structures.