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Recent research results show that great progress has been made in improving the generation rate of physical random numbers. However, there are still some defects such as complex generation process and large volume. To solve these problems, this paper theoretically proposes a scheme for generating random numbers using mode hopping of Vertical Cavity Surface Emitting Laser (VCSEL) with optical feedback. The VCSEL is perturbed by the optical feedback to generate the mode hopping. The square wave signal then modulates the injection current, periodically restarts the VCSEL to switch from the non-emitting state to the mode hopping state, and finally outputs a random pulse sequence to realize the random number generation. The results of this paper show that unbiased random numbers with verified randomness can be generated continuously at a rate of the order of Gbit/s. Our scheme eliminates the need for optoelectronic conversion and post-processing operations, simplifing the current random number generation structure, which has the potential to realize a low-cost photonic integrated random number generator.

Pamir yak milk is considered to be ideal food for local people, but its nutritional profile has not yet been reported. This study investigated the chemical and nutritional composition of Pamir yak milk, and compared the results with reference composition of goat and cow milk. We found that the Pamir yak milk had higher contents of protein (4.30%), fat (4.63), lactose (5.21%) and total solid (14.84%) than that of goat and cow milk. The predominant amino acids were glutamate (20%), proline (10%), lysine (10%) and leucine (10%), of which the essential amino acids accounted for 48% of the total amino acids. Meanwhile, Pamir yak milk was rich in minerals such as Ca, Fe, Zn and Mg and thiamine (B1), niacin (B3), Pyridoxine (B6) and cobalamin (B12) were higher than those of cow and goat milk. Also, medium‐chain fatty acids (C12−C16) exhibited the highest level. However, The α ‐linolenic acid (C18:3), eicosapentaenoic acid and docosahexaenoic acid were found in yak milk. All of the above‐mentioned differences were demonstrated by the fact that the yak milk quality may be affecting by pasture production, animal species and nutritive value of the herbage. Therefore, Pamir yak milk is a promising alternative food that may contribute to human health. [ABSTRACT FROM AUTHOR]

Five different strains including Lactobacillus plantarum, Pediococcus acidilactici, Lactobacillus acidophilus, Lactobacillus paracasein and Lactobacillus rhamnosus were used to ferment blueberry jiaosu. Using superoxide dismutase (SOD) activity, total soluble solids (TSS) content, and pH value as indicators, in the beginning, uniform design was used to determine the best inoculation ratio of five different strains. Secondly, there were four single factor experiments including fermentation time, temperature, initial bacterial density and initial TSS contend. Finally, the fermentation process was optimized by response surface method. The goal of this work is fermenting blueberry jiaosu products with high SOD activity. The results showed that the optimal inoculation ratios of Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus acidophilus, Lactobacillusparacasei, and Lactobacillus rhamnosus are 22.45%, 42.86%, 14.29%, 16.33%, 4.10%, respectively. The optimized fermentation conditions are: 36 h of time, 37 °C of temperature, 5.5*106 CFU/mL of the initial inoculation amount, 11 °Brix of the initial TSS content. After fermentation, the SOD activity of blueberry jiaosu finally reached 87.45 U/g. In summary, this study optimized the best inoculation ratio of multiple strains through uniform design and optimized the optimal fermentation process through response surface methodology. [ABSTRACT FROM AUTHOR]

Twin-Field quantum key distribution (TF-QKD) and its variants, e.g. phase-maching QKD, sending-or-not-sending QKD, and no phase post-selection TFQKD promise high key rates at long distance to beat the rate distance limit without a repeater. The security proof of these protocols are based on decoy-state method, which is usually performed by actively modulating a variable optical attenuator together with a random number generator in practical experiments, however, active-decoy schemes like this may lead to side channel and could open a security loophole. To enhance the source security of TF-QKD, in this paper, we propose passive-decoy based TF-QKD, in which we combine TF-QKD with the passive-decoy method. And we present a simulation comparing the key generation rate with that in active-decoy, the result shows our scheme performs as good as active decoy TF-QKD, and our scheme could reach satisfactory secret key rates with just a few photon detectors. This shows our work is meaningful in practice. [ABSTRACT FROM AUTHOR]