Full space coordinate measurement method with a portable light pen by using hybrid light field imaging.

The light pen is one of the most useful spatial coordinate measurement methods. However, due to the principle of vision measurement, the traditional light pen has the disadvantages such as limited measurement range, large structure size and complex calibration process. In order to revolutionize the design of light pen, this paper proposes a full space coordinate measurement method with a portable light pen by using hybrid light field imaging. Firstly, a light field imaging system with depth estimation ability has been introduced to simplify the light pen structure to three target points by using P3P method. In order to improve the accuracy of the depth estimation, a hybrid imaging method and EPI method have been used. Secondly, a full spatial measurement method with a rotation platform has been presented in detail. Finally, the experiments have been designed to verify the effectiveness and accuracy of the proposed method.

The Research Progress on the Interaction between Mammalian Gut Microbiota and the Host's Metabolism Homeostasis during Hibernation.

Hibernating mammals confront seasonal and harsh environmental shifts, prompting a cycle of pre-hibernation feeding and subsequent winter fasting. These adaptive practices induce diverse physiological adjustments within the animal's body. With the gut microbiota's metabolic activity being heavily reliant on the host's diet, this cycle's primary impact is on this microbial community. When the structure and composition of the gut microbiota changes, corresponding alterations in the interactions occur between these microorganisms and their host. These successive adaptations significantly contribute to the host's capacity to sustain relatively stable metabolic and immune functions in severe environmental conditions. A thorough investigation into the reciprocal interplay between the host and gut microbiota during hibernation-induced adaptive changes holds promise for unveiling new insights. Understanding the underlying mechanisms driving these interactions may potentially unlock innovative approaches to address extreme pathological conditions in humans.

Seasonal Changes in the Structure and Function of Gut Microbiota in the Muskrat (Ondatra zibethicus).

The gut microbiota plays a crucial role in the nutrition, metabolism, and immune function of the host animal. The muskrat (Ondatra zibethicus) is a typical seasonal breeding animal. The present study performed a metagenomic analysis of cecum contents from muskrats in the breeding and non-breeding seasons. The results indicated that the breeding muskrats and non-breeding muskrats differed in gut microbiota structure and function. During the breeding season, the relative abundance of phylum Bacteroidetes, genus Prevotella, and genus Alistipes increased, while the relative abundance of phylum Firmicutes and phylum Actinobacteria decreased. The muskrat gut microbiota was enriched in the metabolism-related pathways, especially amino acid and vitamin metabolism, and genetically related metabolites in the breeding season. We presumed that the muskrat gut microbiota might seasonally change to secure reproductive activity and satisfy the metabolic demands of different seasons. This study could explore potential mechanisms by which gut microbiota affects reproduction. Moreover, this study may provide a new theoretical basis for the management of muskrat captive breeding.

Seasonal Variation in Gut Microbiota of the Wild Daurian Ground Squirrel (Spermophilus dauricus): Metagenomic Insights into Seasonal Breeding.

The Spermophilus dauricus, the wild Daurian ground squirrel, is known to exhibit seasonal breeding behavior. Although the importance of gut microbiota in animal digestion, metabolism, and immunity is well-established, the correlation between gut microbiota and seasonal breeding in this species remains inadequately explored. In the present study, using metagenomic sequencing technology, the compositions and functions of the gut microbiota of wild Daurian ground squirrels in different breeding seasons were explored. The dominant gut microbial phyla were Firmicutes and Bacteroidetes. The Firmicutes were predominant in the breeding season, whereas Bacteroidetes were predominant in the non-breeding season. At the genus level, Lactobacillus accumulated during the breeding season, whereas Odoribacter and Alistipes increased during the non-breeding season. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genome) annotations indicated that genes in gut samples were highly associated with metabolic functions. The differential expression gene analysis showed that genes related to the phosphotransferase system, cysteine, and methionine metabolism were highly expressed during the breeding season, whereas the non-breeding season upregulated genes were enriched in starch and sucrose metabolism and bacterial chemotaxis pathways. In conclusion, this study could provide a reference for investigating gut microbiota in seasonal breeding animals and offer new insight into gut microbial function.

Seasonal expressions of GPR41 and GPR43 in the colon of the wild ground squirrels (Spermophilus dauricus).

G-protein-coupled receptor 41 (GPR41) and G-protein-coupled receptor 43 (GPR43) are important short-chain fatty acids (SCFAs) receptors. Previous studies indicated that GPR41 and GPR43 are involved in the secretion of gastrointestinal peptides, and glucose and lipid metabolism, and are closely related to obesity and type II diabetes, and other diseases. The purpose of the study was to explore the relationship between the GPR41 and GPR43 and seasonal breeding, and provide new prospects for further exploring the nutritional needs of breeding. We identified the localization and expression levels of GPR41 and GPR43 in the colon of the wild ground squirrels (Spermophilus dauricus) both in the breeding season and non-breeding season. The histological results revealed that the lumen diameter of the colon had obvious seasonal changes, and the diameter of the colonic lumen in the non-breeding season was larger than that in the breeding season. Immunohistochemical staining suggested GPR41 and GPR43 have expressed in the simple layer columnar epithelium. In addition, compared with the breeding season, the mRNA and protein expression levels of GPR41 and GPR43 in the colon were higher during the non-breeding season. In general, these results indicated GPR41 and GPR43 might play a certain role in regulating seasonal breeding.