Multi-UAV Path Planning in GPS and Communication Denial Environment.

This paper proposes a feature fusion algorithm for solving the path planning problem of multiple unmanned aerial vehicles (UAVs) using GPS and communication denial conditions. Due to the blockage of GPS and communication, UAVs cannot obtain the precise position of a target, which leads to the failure of path planning algorithms. This paper proposes a feature fusion proximal policy optimization (FF-PPO) algorithm based on deep reinforcement learning (DRL); the algorithm can fuse image recognition information with the original image, realizing the multi-UAV path planning algorithm without an accurate target location. In addition, the FF-PPO algorithm adopts an independent policy for multi-UAV communication denial environments, which enables the distributed control of UAVs such that multi-UAVs can realize the cooperative path planning task without communication. The success rate of our proposed algorithm can reach more than 90% in the multi-UAV cooperative path planning task. Finally, the feasibility of the algorithm is verified by simulations and hardware.

Transplantion of predominant Lactobacilli from native hens to commercial hens could indirectly regulate their ISC activity by improving intestinal microbiota.

In poultry, HyLine (HL) Hens are known for their excellent laying performance. However, ZhenNing (ZN) Hens, a native chicken breed in China, are known for their unique flavour. The intestinal mucosa, which is the main organ for nutrient absorption, could affect livestock product quality. In ZN Hens' intestinal mucosa, we found more villus wrinkles, larger villus circumference and higher amino acid transporters mRNA abundance compared with HL Hens. Among three laying periods of ZN Hens, in the intestinal lumen, Lactobacillus salivarius (L. sa.), Lactobacillus agilis (L. ag.) and Lactobacillus aviarius were the predominant species in the laying peak period. Furthermore, multiple-antibiotics feeding in ZN Hens and predominant Lactobacillus feeding in HL Hens suggested that these Lactobacilli could indeed increase villus wrinkles and improve intestinal absorption. In HL Hens, L. sa. + L. ag. treatment could promote organoids budding in vitro, and promote epithelial proliferation in vivo. Collectively, the unique intestinal mucosa morphology in ZN Hens was due to the high abundance of intestinal L. sa. and L. ag. Transplant these Lactobacilli to HL Hens could increase their intestinal probiotics abundance, fine adjust the intestinal stem cell function and promote the epithelial proliferation, in turn, increase villus winkles and mucosal absorption area.

Lactobacillus salivarius and Lactobacillus agilis feeding regulates intestinal stem cells activity by modulating crypt niche in hens.

Previously, we found that Lactobacillus salivarius, Lactobacillus agilis, and Lactobacillus aviarius were associated with excellent egg nutrition in native chicken. Next, the optimal Lactobacillus combination is worth studying. Here, a total of 120 HyLine hens (30 hens per group contained 3 replicate cells, 10 hens/cell) in the laying peak period were randomly divided into (1) control, (2) L. salivarius + L. agilis, (3) L. salivarius + L. aviarius, and (4) L. agilis + L. aviarius groups, fed with diet only or with corresponding Lactobacilli (108 colony-forming units/hen/day) for 30 days. As a result, L. salivarius + L. agilis feeding could (1) improve egg-laying rate, egg weight, and albumen's amino acid levels; (2) increase Lactobacillus abundance, decrease Escherichia coli abundance, upregulate the tryptophan metabolism pathway-related molecules, and downregulate the primary bile acid biosynthesis pathway-related molecules in intestinal contents; and (3) upregulate oxidative-phosphorylation pathway-related genes, reactive oxygen species levels, and mRNA abundance of Wnt3a, Dll1, Lgr5, CCDN1, and CDK2 in the crypt. Collectively, L. salivarius + L. agilis feeding in hens could improve intestinal microflora and metabolism profile, promote crypt's local energy metabolism and reactive oxygen species levels, and thus enhance Paneth cells and intestinal stem cells activity.Key points• Lactobacilli co-feeding could improve laying performance and egg nutrition.• Lactobacilli co-feeding could improve intestinal microflora and metabolism profile.• Lactobacilli co-feeding could enhance Paneth cells and intestinal stem cells activity.

Paneth cells mediated the response of intestinal stem cells at the early stage of intestinal inflammation in the chicken.

The rapid renewal and repair of the intestinal mucosa are based on intestinal stem cells (ISC), which are located at the crypt bottom. Paneth cells are an essential component in the crypt, which served as the niche for ISC development. However, in the chicken, how the function of Paneth cells changes during intestinal inflammation is unclear and is the key to understand the mechanism of mucosal repair. In the present study, 36 HyLine White chickens (7 d of age, n = 6) were randomly divided into 1 control and 5 lipopolysaccharide (LPS) injection groups. The chickens were injected (i.p.) with PBS in the control group, however, were injected (i.p.) with LPS (10 mg/kg BW) in the LPS injection groups, which would be sampled at 5 time points (1 h postinjection [hpi], 2 hpi, 4 hpi, 6 hpi, and 8 hpi). Results showed that tumor necrosis factor-α mRNA transcription in duodenal tissue increased gradually since 1 hpi, peaked at 4 hpi, and then reduced remarkably, indicating that 4 hpi of LPS was the early stage of intestinal inflammation. Meanwhile, the MUC2 expression in duodenal tissue was dramatically reduced since 1 hpi of LPS. The ISC marker, Lgr5 and Bmi1, in the duodenal crypt were reduced from 1 hpi to 4 hpi and elevated later. Accordingly, the hydroethidine staining showed that the reactive oxygen species level, which drives the differentiation of ISC, in the duodenal crypt reduced obviously at 1 hpi and recovered gradually since 4 hpi. The analysis of Paneth cells showed that many swollen mitochondria appeared in Paneth cells at 4 hpi of LPS. Meanwhile, the Lysozyme transcription in the duodenal crypt was substantially decreased since 1 hpi of LPS. However, the Wnt3a and Dll1 in duodenal crypt decreased at 1 hpi of LPS, then increased gradually. In conclusion, Paneth cells were impaired at the early stage of intestinal inflammation, then recovered rapidly. Thus, the ISC activity was reduced at first and recovery soon.