Search

In virtual reality interactive input systems, real-time and accurate spatial position and pose measurement is key to achieving a natural user interface. This study explores the application of inertial measurement units and binocular vision fusion technology in virtual reality interactive input systems, with the aim of improving the tracking accuracy of the system through optimized pose models and visual algorithms. A virtual reality measurement technology that integrates inertial measurement units and binocular vision is proposed by using an improved Kalman filtering algorithm to process inertial measurement units data, and combining it with the SURF algorithm optimized binocular vision system. Experimental results showed that fusion technology could reduce sensor noise and bias, improve the accuracy of pose estimation, and promote stable and robust motion tracking in virtual reality systems. In the angle range of -90 ° to 90 °, the average absolute error of the fusion system compared to the simple inertial measurement units pose calculation decreased from 3.371 ° to 1.369 ° In the experiment of measuring distance with a binocular vision system, the average absolute error value decreased to 1.532 mm, and the error range of the marker within the distance range of 500 mm to 650 mm was controlled within -1.3 mm to 1.2 mm. This study provides an effective solution for achieving high-precision virtual reality interactive input systems and is meaningful for the advancement of virtual reality technology.

The intestinal tract plays an important role in digestion and absorption, nutrient metabolism, and immune anti-stress. At the same time, the intestine is also the major site for pathogens and various harmful substances to invade. Probiotics, as living microbial agents, improve animal health by maintaining the microecological balance of the host's intestinal flora. To explore the protective effect of Clostridium butyricum (CB) on the gut, we investigated the changes in digestion, antioxidant, and gut microbiota in juvenile largemouth bass. The fish were fed with diets containing 0 (control, CB0), 4.3×108 (CB1), 7.5×108 (CB2), 1.5×109 (CB3), and 3.2×109 (CB4) CFU/kg Clostridium butyricum for 56 days. After 56 days of dietary supplementation with 4.3×108 and 3.2×109 CFU/kg of CB, significant growth promotion and feed utilization improvement were observed in largemouth bass (P < 0.05). The activities of digestive enzymes (trypsin, protease and amylase) and intestinal functional indicators (sodium-potassium ATP, γ-GT and CK) were significantly increased in the intestine of largemouth bass (P < 0.05). The contents of intestinal short-chain fatty acids (acetic acid, propionic acid, isobutyric acid, N-butyric acid and isovaleric acid) in largemouth bass were significantly increased (P < 0.05). CB significantly increased the activities of antioxidant enzymes (T-AOC, CAT, POD, GSH-Px and SOD) and decreased the content of MDA in the intestine of largemouth bass (P < 0.05). It was also observed that CB significantly increased the activities of immune-related markers lysozyme and alkaline phosphatase (P < 0.05). High-throughput sequencing of the 16 S rRNA gene in largemouth bass revealed a significant increase in gut microbial richness. KEGG pathway analysis showed that CB had significant effects on intestinal microbiota functions, such as nutrient metabolism and energy conversion. The results showed that CB could stimulate intestine to produce the organic product butyric acid, which was customized in the gut to enhance digestive performance, promote nutrient metabolism, and protect microbial homeostasis in the intestinal tract of largemouth bass. These results provide new insights into the protective effects of CB on the intestinal tract of aquatic animals.

The aim of this study was to investigate the effects of arginine supplementation on liver morphology, antioxidant capacity, inflammatory response, insulin signaling pathway and glucose metabolism in hybrid snakehead. Five experimental diets (2.31 %, 2.42 %, 2.72 %, 2.92 %, and 3.12 % arginine) were prepared by adding different levels of arginine to the basal diet containing high (27 %) level of carbohydrate. The results showed that the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione peroxidase (GSH-Px) of fish fed with arginine diets were significantly higher than those in control group (p

Introduction: The functional relevance of intra-species diversity in natural microbial communities remains largely unexplored. The guts of two closely related honey bee species, Apis cerana and A. mellifera, are colonised by a similar set of core bacterial species composed of host-specific strains, thereby providing a good model for an intra-species diversity study. Objectives: We aim to assess the functional relevance of intra-species diversity of A. cerana and A. mellifera gut microbiota. Methods: Honey bee workers were collected from four regions of China. Their gut microbiomes were investigated by shotgun metagenomic sequencing, and the bacterial compositions were compared at the species level. A cross-species colonisation assay was conducted, with the gut metabolomes being characterised by LC-MS/MS. Results: Comparative analysis showed that the strain composition of the core bacterial species was host-specific. These core bacterial species presented distinctive functional profiles between the hosts. However, the overall functional profiles of the A. cerana and A. mellifera gut microbiomes were similar; this was further supported by the consistency of the honey bees’ gut metabolome, as the gut microbiota of different honey bee species showed rather similar metabolic profiles in the cross-species colonisation assay. Moreover, this experiment also demonstrated that the gut microbiota of A. cerana and A. mellifera could cross colonise between the two honey bee species. Conclusion: Our findings revealed functional differences in most core gut bacteria between the guts of A. cerana and A. mellifera, which may be associated with their inter-species diversity. However, the functional profiles of the overall gut microbiomes between the two honey bee species converge, probably as a result of the overlapping ecological niches of the two species. Our findings provide critical insights into the evolution and functional roles of the mutualistic microbiota of honey bees and reveal that functional redundancy could stabilise the gene content diversity at the strain-level within the gut community.

The alarming increase in soil contamination by heavy metals, such as cadmium and zinc demands immediate attention. The dioecious tree Populus cathayana, a phytoremediation plant, plays an important role in rehabilitating heavy metal contaminated areas. In this study, male and female P. cathayana plants were treated with Cd (20 mg kg−1) and different levels of Zn (25, 50, or 100 mg kg−1) to study their physiological responses. The results showed that Cd exposure alone caused stress by inhibiting the growth of both male and female plants. In both males and females, photosynthesis and antioxidant enzymes activities decreased substantially under Cd stress alone. Cd was largely located in the roots, but Zn was present in the shoots of both sexes. Zn supplementation considerably increased the photosynthetic rate from 14.62 % to 60.45 % and also enhanced the antioxidant enzymes activities from 24.11 % to 86.21 %. Zn treatment decreased the translocation ability of Cd compared to the Cd-only treatment, alleviating Cd toxicity. In addition, when sufficient Zn was made available, males showed a high degree of Cd accumulation, low root-to-shoot translocation, elevated antioxidant defense abilities, and an increased photosynthetic rate, while females were less responsive to Cd stress than males. Thus, combined exposure to Cd and Zn caused differential responses in plant growth and physiological processes between males and females P. cathayana. Male plants exhibit better Cd tolerance and accumulation capacity under optimum Zn supplementation. This study increases the fundamental knowledge regarding P. cathayana plants, which can be applied to enhance their remediation capacity in Cd-contaminated soils.

The effects of dietary tributyrin (TB) on growth, intestinal health, inflammatory response and antioxidant status in juvenile Pelteobagrus fulvidraco were investigated. The fish (initial weight 5.53 ± 0.02 g) were fed with diets containing 0 (control, TB0), 500 (TB1), 1000 (TB2) and 2000 (TB3) mg/kg tributyrin for 56 days. The results showed that significantly higher final weight, specific growth rate, protein efficiency ratio and protein retention were observed in fish fed with TB2 diet compared with those in TB0 (P

A 100-d feeding trial was conducted to evaluate the effects of replacing soybean meal (SBM) and rapeseed meal (RSM) with faba bean meal (FBM) on growth performance and muscle quality of tilapia. A total of 600 fish (initial body weight 500.2 ± 0.34 g) were randomly distributed into 4 groups with 3 replicates per group and 50 fish per replicate. Four diets were formulated to replace SBM and RSM with FBM at the rate of 0 % (R0), 25 % (R25), 50 % (R50) and 100 % (R100). Results showed that FBM substitute diets did not significantly alter (P > 0.05) the weight gain rate, specific growth rate, feed conversion ratio, feed intake and viscerosomatic index, but increased (P 0.05) essential amino acids, but increased (P

The effects of arginine on intestinal shape, digestive enzyme activity, antioxidant capacity, and intestinal flora of hybrid snakeheads Channa maculata♀×Channa argus♂. Five experimental diets were formulated to contain arginine with 2.31%, 2.42%, 2.72%, 2.92%, and 3.12% respectively, and recorded as G1 (control), G2, G3, G4, and G5. Five groups of 50 fish (22.02 ± 0.02 g) for each diet were fed to apparent satiation twice daily for 56 days. The results showed that significantly higher weight gain (WG), specific growth rate (SGR), protein deposition rate (PDR), intestinal somatic indices (ISI), lipase, trypsin, Na+/K+-ATPase, γ-glutamyl transpeptidase, and significantly lower feed coefficient rate (FCR) were observed in fish fed with 2.92% diet compared to 2.31% group (P

The experimental trial was conducted to assess the effects of dietary pyridoxine on growth performance, physiological metabolics, intestinal enzymatic activities and antioxidant properties of Pelteobagrus fulvidraco. Six isonitrogenous and isolipidic diets (420 g/kg protein and 70 g/kg lipid) were formulated to contain 3.69 (control), 5.45, 7.31,11.17, 19.43 and 33.94 mg/kg pyridoxine. Four groups of 30 fish (3.85 ± 0.01 g) per tank (300-L cylindrical fiberglass tanks) for each diet were fed to apparent satiation twice daily for 63 days. Blood, intestine and hepatopancreas samples were obtained for metabolic, enzymatic activities and antioxidant properties analyses. The results showed that significantly higher weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), protein retention efficiency (PRE), whole-body crude protein, intestinal protease, alkaline phosphatase, Na+/K+-ATPase, γ-glutamyl transpeptidase and significantly lower feed conversion ratio were observed in fish fed diet with 7.31 mg/kg compared to those in control group (P

In this study, the copper oxide nanoparticles (CuO NPs) were synthesized using marine entophytic actinomycetes as reducing and stabilizing agent through biological route. The actinomycetes mediated CuO NPs were physico-chemically characterized through X-ray diffractometer (XRD), thermogravimetric (TGA) analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD result suggested the actinomycetes mediated CuO purity and TEM analysis was examined the morphology (spherical), average size (∼20 nm) of actinomycetes mediated CuO NPs. Further, at the concentration of 750 µg/mL, the CuO NPs exhibited excellent anti-bacterial properties, and shown 24 mm and 28 mm zones against biofilm producing E. coli and P. mirabilis. Further, the biofilm eradication efficiency was confirmed by 24-well polystyrene method with 24 h time duration and the result of 1000 µg/mL were shown 92% and 94% alteration against biofilm producing E. coli and P. mirabilis at 600 nm O.D using spectrophotometer. Further, the cytotoxicity assay of CuO NPs against A549 lung cancer cells result was shown more necrotic and irregular morphology of cancer cells. At 500 µg/mL concentration, 54% inhibition range against A549 cancer cells were observed, and it damaged completely due to the more intracellular formazan production. Altogether, the current result was suggested that the rich phytochemicals and bioactive compound producing actinomycetes were highly influenced the CuO NPs growth and enhanced the biological properties against tested biofilm bacteria and A549 lung cancer cells. Hence, we have concluded that the actinomycetes mediated CuO NPs has excellent biomedical applications against biofilm producing bacteria and cancer cells, and it were used future studies of various biomedical applications.

Low-salinity tolerance and growth are crucial economic traits of shrimp in areas with low-salinity water. In the current study, an F1 full-sib family of Pacific white shrimp (Litopenaeus vannamei) was obtained by the “semidirectional cross” method, and 2 parents and 146 progenies were genotyped using double-digest restriction site-associated DNA sequencing technology (ddRAD-Seq). A total of 3335 high-quality markers were identified and used to construct a genetic linkage map. This genetic map comprised 48 linkage groups (LGs), and the total map length spanned 3954.462 centimorgan (cM) with an average marker interval of 1.186 cM. Three quantitative trait loci (QTLs) for low-salinity tolerance and 3 QTLs for growth (body weight) were detected under the condition of restricted logarithmic odds (LOD) score ≥ 2.50. With the assistance of the genome of L. vannamei and relevant annotations, 3 potential growth-related genes (sob, TJP1 and ZBTB24) and 3 low-salinity response candidate genes (Rnf168, CNOT2 and RPB3) were identified from the genomic scaffolds. Moreover, the qPCR results showed that the expression levels of the 3 candidate genes were significantly affected by low-salinity stress, indicating that they possibly play an important role in low-salinity stress. Here, we present the first report of mapping of low-salinity tolerance QTLs in the genetic mapping of L. vannamei, which will be beneficial for the selection of shrimp breeding markers and might help promote the study of the L. vannamei genome.

Although effects of dietary condensed tannins (CT) on growth and health of fish have been evaluated, limited information is available on shrimp. This study investigated the effects of CT on growth, nutrient digestibility, antioxidant response and intestinal histomorphology of Litopenaeus vannamei. A 56-day feeding trial was conducted by randomly distributing 600 shrimp into 15 tanks with 40 shrimp per tank and fed five diets containing 0 (G0), 0.5 (G0.5), 1 (G1), 2 (G2) and 4 (G4) g/kg of grape seed CT respectively. Shrimp were fed to apparent satiation during the entire feeding trial and feces were collected daily for the last 14 days to determine nutrient digestibilities. Hepatopancreas and intestine samples were collected to analyze antioxidant-related genes expression and histomorphology. Results indicated that dietary CT linearly increased final body weight, weight gain rate and specific growth rate (0.05 0.05). As compared with G0, dietary CT increased superoxide dismutase (G0.5, G1 and G2), glutathion peroxidase (G1 and G2) and nuclear factor erythroid 2-related factor 2 (G0.5, G1, G2 and G4) mRNA levels (P

Condensed tannins (CT) have been observed to be beneficial to maintain glucose homeostasis and improve carbohydrate utilization for livestock, whereas little information is available about the effects of CT on glycometabolism of fish. Three diets were formulated to contain approximately 15 % carbohydrate (G1), 39 % carbohydrate (G2), and G2 supplemented with 0.1 % CT. A total of 225 juvenile Lateolabrax japonicus were randomly assigned to 3 groups (triplicate tanks per group) with 25 fish in each tank and fed to apparent satiation during 56-d feeding trial. Results indicated that fish fed G2 had lower (p < 0.05) final body weight, weight gain rate, feed intake, specific growth rate and serum insulin concentration, but higher (p < 0.05) feed efficiency ratio and serum glucose, total antioxidant capacity, superoxide dismutase, immunoglobulin M and lipopolysaccharide than those fish fed G1 or G3. The activity of pyruvate kinase (PK) was lower (p < 0.05) but glucokinase (GK) was higher (p < 0.05) in G2 than in G1 or G3. Gene expression of insulin like growth factor Ⅰ and PK were down-regulated (p < 0.05), whereas GK was up-regulated (p < 0.05) in G2 than in G1 or G3. No difference (p> 0.05) in these gene expressions were observed between G1 and G3. It was concluded that L. japonicus fed diet with 39 % carbohydrate exhibited depressed growth performance, increased antioxidant and immune capacity, and hyperglycemia. Supplementation of 0.1 % CT resulted in improved growth performance and decreased serum glucose concentration, mainly due to the positive effects of CT on the activity and gene expression of hepatic glycolysis and gluconeogenesis enzymes of L. japonicus.

Primates of the Colobinae subfamily are highly folivorous. They possess a sacculated foregut and are believed to rely on a specialized gut microbiota to extract sufficient energy from their hard-to-digest diet. Although many colobines are endangered and would benefit from captive breeding programs, maintaining healthy captive populations of colobines can be difficult since they commonly suffer from morbidity and mortality due to gastrointestinal (GI) distress of unknown cause. While there is speculation that this GI distress may be associated with a dysbiosis of the gut microbiota, no study has directly examined the role of the gut microbiota in colobine GI health. In this study, we used high-throughput sequencing to examine the gut microbiota of three genera of colobines housed at the San Diego Zoo: doucs (Pygathrix) (N=7), colobus monkeys (Colobus) (N=4), and langurs (Trachypithecus) (N=5). Our data indicated that GI-healthy doucs, langurs, and colobus monkeys possess a distinct gut microbiota. In addition, GI-unhealthy doucs exhibited a different gut microbiota compared to GI-healthy individuals, including reduced relative abundances of anti-inflammatory Akkermansia. Finally, by comparing samples from wild and captive Asian colobines, we found that captive colobines generally exhibited higher relative abundances of potential pathogens such as Desulfovibrio and Methanobrevibacter compared to wild colobines, implying an increased risk of gut microbial dysbiosis. Together, these results suggest an association between the gut microbiota and GI illness of unknown cause in doucs. Further studies are necessary to corroborate these findings and determine cause-and-effect relationships. Additionally, we found minimal variation in the diversity and composition of the gut microbiota along the colobine GI tract, suggesting that fecal samples may be sufficient for describing the colobine gut microbiota. If these findings can be validated in wild individuals, it will facilitate the rapid expansion of colobine gut microbiome research.

Lipolytic modification of LDL particles by SMase generates LDL aggregates with a strong affinity for human arterial proteoglycans and may so enhance LDL retention in the arterial wall. Here, we evaluated the effects of apoA-I mimetic peptide 4F on structural and functional properties of the SMase-modified LDL particles. LDL particles with and without 4F were incubated with SMase, after which their aggregation, structure, and proteoglycan binding were analyzed. At a molar ratio of L-4F to apoB-100 of 2.5 to 20:1, 4F dose-dependently inhibited SMase-induced LDL aggregation. At a molar ratio of 20:1, SMase-induced aggregation was fully blocked. Binding of 4F to LDL particles inhibited SMase-induced hydrolysis of LDL by 10% and prevented SMase-induced LDL aggregation. In addition, the binding of the SMase-modified LDL particles to human aortic proteoglycans was dose-dependently inhibited by pretreating LDL with 4F. The 4F stabilized apoB-100 conformation and inhibited SMase-induced conformational changes of apoB-100. Molecular dynamic simulations showed that upon binding to protein-free LDL surface, 4F locally alters membrane order and fluidity and induces structural changes to the lipid layer. Collectively, 4F stabilizes LDL particles by preventing the SMase-induced conformational changes in apoB-100 and so blocks SMase-induced LDL aggregation and the resulting increase in LDL retention.

Bin-Amphiphysin-Rvs (BAR) domain proteins are central regulators of many cellular processes involving membrane dynamics. BAR domains sculpt phosphoinositide-rich membranes to generate membrane protrusions or invaginations. Here, we report that, in addition to regulating membrane geometry, BAR domains can generate extremely stable lipid microdomains by “freezing” phosphoinositide dynamics. This is a general feature of BAR domains, because the yeast endocytic BAR and Fes/CIP4 homology BAR (F-BAR) domains, the inverse BAR domain of Pinkbar, and the eisosomal BAR protein Lsp1 induced phosphoinositide clustering and halted lipid diffusion, despite differences in mechanisms of membrane interactions. Lsp1 displays comparable low diffusion rates in vitro and in vivo, suggesting that BAR domain proteins also generate stable phosphoinositide microdomains in cells. These results uncover a conserved role for BAR superfamily proteins in regulating lipid dynamics within membranes. Stable microdomains induced by BAR domain scaffolds and specific lipids can generate phase boundaries and diffusion barriers, which may have profound impacts on diverse cellular processes.