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Abstract Objective Anesthetics have been linked to cognitive alterations, particularly in the elderly. The current research delineates how Fibroblast Growth Factor 2 (Fgf2) modulates tau protein phosphorylation, contributing to cognitive impairments in aged rats upon sevoflurane administration. Methods Rats aged 3, 12, and 18 months were subjected to a 2.5% sevoflurane exposure to form a neurotoxicity model. Cognitive performance was gauged, and the GEO database was employed to identify differentially expressed genes (DEGs) in the 18-month-old cohort post sevoflurane exposure. Bioinformatics tools, inclusive of STRING and GeneCards, facilitated detailed analysis. Experimental validations, both in vivo and in vitro, examined Fgf2’s effect on tau phosphorylation. Results Sevoflurane notably altered cognitive behavior in older rats. Out of 128 DEGs discerned, Fgf2 stood out as instrumental in regulating tau protein phosphorylation. Sevoflurane exposure spiked Fgf2 expression in cortical neurons, intensifying tau phosphorylation via the PI3K/AKT/Gsk3b trajectory. Diminishing Fgf2 expression correspondingly curtailed tau phosphorylation, neurofibrillary tangles, and enhanced cognitive capacities in aged rats. Conclusion Sevoflurane elicits a surge in Fgf2 expression in aging rats, directing tau protein phosphorylation through the PI3K/AKT/Gsk3b route, instigating cognitive aberrations.

The Arctic fox (Vulpes lagopus) is a species indigenous to the Arctic and has developed unique lipid metabolism, but the mechanisms remain unclear. Here, the significantly increased body weight of Arctic foxes was consistent with the significantly increased serum very-low-density lipoprotein (VLDL), and the 40% crude fat diet further increased the Arctic fox body weight. The enhanced body weight gain stems primarily from increased subcutaneous adipose tissue accumulation. The adipose triacylglycerol and phosphatidylethanolamine were significantly greater in Arctic foxes. The adipose fatty-acid synthase content was significantly lower in Arctic foxes, highlighting the main role of exogenous fatty-acids in fat accumulation. Considering the same diet, liver-derived fat dominates adipose expansion in Arctic foxes. Liver transcriptome analysis revealed greater fat and VLDL synthesis in Arctic foxes, consistent with the greater VLDL. Glucose homeostasis wasn’t impacted in Arctic foxes. And the free fatty-acids in adipose, which promote insulin resistance, also did not differ between groups. However, the hepatic glycogen was greater in Arctic foxes and transcriptome analysis revealed upregulated glycogen synthesis, improving glucose homeostasis. These results suggest that the superior fat accumulation capacity and distinct characteristics of hepatic and adipose lipid and glucose metabolism facilitate glucose homeostasis and massive fat accumulation in Arctic foxes.

To address the issue of high resistance encountered by traditional chisel-shaped shovel tips during tillage, this study drew inspiration from the micro V-shaped structures found in shark skin. Using laser cladding technology, a V-shaped wear-resistant coating was applied to the front surface of the shovel, with different drag-reducing V-shaped structures achieved by controlling the coating overlap ratio H (including 20%, 40%, and 60%). Additionally, the rear surface of the shovel tip was designed to mimic the V-shaped morphology of shark skin, proportionally amplified, and given a certain backward tilt angle θ to further reduce resistance. Through the discrete element simulation experiments while maintaining θ at 0°, it was found that the shovel tip achieved the best drag reduction effect when H was 40%. Based on this, the study varied the values of θ (including 0°, 1°, 3°, and 5°) while keeping H at 40%. Discrete element simulation experiments were conducted at depths of 250mm, 275mm, and 300mm to analyze the disturbance effect, fragmentation effect, and resistance of the shovel tip. Considering all factors, the shovel tip with θ of 5° was selected as the optimal choice. Finally, a soil trench experiment was conducted to verify the performance of the V-shaped shovel tip with H of 40% and θ of 5°, as well as the chisel-shaped shovel tip, in tillage operations. The experimental results showed good agreement with the simulation results, and the designed V-shaped shovel tip achieved a maximum drag reduction of 12.87%. This design provides valuable references for the structural optimization of subsoiler, contributing to the improvement of their performance and efficiency.

From quantum communications to quantum computing, single-photon emitters (SPEs) are essential components of numerous quantum technologies. Two-dimensional (2D) materials have especially been found to be highly attractive for the research into nanoscale light–matter interactions. In particular, localized photonic states at their surfaces have attracted great attention due to their enormous potential applications in quantum optics. Recently, SPEs have been achieved in various 2D materials, while the challenges still remain. This paper reviews the recent research progress on these SPEs based on various 2D materials, such as transition metal dichalcogenides (TMDs), hexagonal boron nitride (hBN), and twisted-angle 2D materials. Additionally, we summarized the strategies to create, position, enhance, and tune the emission wavelength of these emitters by introducing external fields into these 2D system. For example, pronounced enhancement of the SPEs’ properties can be achieved by coupling with external fields, such as the plasmonic field, and by locating in optical microcavities. Finally, this paper also discusses current challenges and offers perspectives that could further stimulate scientific research in this field. These emitters, due to their unique physical properties and integration potential, are highly appealing for applications in quantum information and communication, as well as other physical and technological fields.

Abstract Background Even if breed, parity, dietary and environmental management are same, dairy cows still have notable differences in milk yield that may be underpinned by physiologic differences. Objectives This study aimed to investigate the physiological dissimilarities of dairy cows with different milk yields. Methods Thirty cows were sorted into high milk‐yielding cows (group H: 58.93±2.31 kg/day), moderate milk‐yielding cows (group M: 44.99±0.54 kg/day), and low milk‐yielding cows (group L: 24.99±6.83 kg/day) according to milk yield. Blood was collected and serum parameters were assessed. Rumen fluid was collected for the evaluation of rumen fermentation parameters (RFPs) and bacterial community composition (BCC). Results Serum prolactin, growth hormone, glutathione peroxidase, immunoglobulin A and non‐esterified fatty acid had a significantly positive correlation with milk yield (p < 0.05), whereas serum glucagon and total antioxidant capacity had a significantly negative correlation with milk yield (p < 0.05). The concentration of valeric acid and the ratio of acetic acid to propionic acid in the rumen fluid in group H was significantly lower than that in group L (p < 0.05). The concentration of acetic acid and butyric acid in group H was significantly lower than that in groups M and L (p < 0.05). The relative abundances of Ruminococcaceae_NK4A214_group, Prevotella_1, Rikenellaceae_RC9_gut_group, Christensenellaceae_R‐7_group, Muribaculaceae, and Ruminococcus_2 were negatively correlated with milk yield, whereas the relative abundance of Succinivibrionaceae_UCG‐001, Lachnospiraceae_NK3A20_group, Shuttleworthia and Dialister were positively correlated with milk yield (p < 0.05). Conclusions This study indicates that dairy cows with different milk yields have clear divergence in serum indicators, RFPs, BCC and rumen microbial metabolism.

Abstract Background The gastrointestinal tract (GIT) microbiome of ruminants and its metabolic repercussions vastly influence host metabolism and growth. However, a complete understanding of the bidirectional interactions that occur across the host-microbiome axis remains elusive, particularly during the critical development stages at early life. Here, we present an integrative multi-omics approach that simultaneously resolved the taxonomic and functional attributes of microbiota from five GIT regions as well as the metabolic features of the liver, muscle, urine, and serum in sika deer (Cervus nippon) across three key early life stages. Results Within the host, analysis of metabolites over time in serum, urine, and muscle (longissimus lumborum) showed that changes in the fatty acid profile were concurrent with gains in body weight. Additional host transcriptomic and metabolomic analysis revealed that fatty acid β-oxidation and metabolism of tryptophan and branched chain amino acids play important roles in regulating hepatic metabolism. Across the varying regions of the GIT, we demonstrated that a complex and variable community of bacteria, viruses, and archaea colonized the GIT soon after birth, whereas microbial succession was driven by the cooperative networks of hub populations. Furthermore, GIT volatile fatty acid concentrations were marked by increased microbial metabolic pathway abundances linked to mannose (rumen) and amino acids (colon) metabolism. Significant functional shifts were also revealed across varying GIT tissues, which were dominated by host fatty acid metabolism associated with reactive oxygen species in the rumen epithelium, and the intensive immune response in both small and large intestine. Finally, we reveal a possible contributing role of necroptosis and apoptosis in enhancing ileum and colon epithelium development, respectively. Conclusions Our findings provide a comprehensive view for the involved mechanisms in the context of GIT microbiome and ruminant metabolic growth at early life. Video Abstract

Abstract Background Silage is achieved by anaerobic fermentation of lactic acid bacteria. However, harvest stage and Lactiplantibacillus plantarum (L. plantarum) content affect the changes of microbial community in silage, which play an important role in silage quality and mycotoxin levels. The current study evaluated the effects exerted by the application of L. plantarum on fermentation, mycotoxins and bacterial community of whole-crop corn silage at different harvest stages. The fresh whole plant corn from the same area was harvested during the milk stage and the dough stage, following which from each harvest stage was subjected to four L. plantarum treatments: 0 cfu/g; 1 × 106 cfu/g; 1 × 107 cfu/g; and 1 × 108 cfu/g in a 2 × 4 factorial experimental design. Samples were collected on days 0, 3, 7, 21 and 42. Subsequently, nutrition parameters, fermentation parameters, mycotoxin levels and bacterial community were determined. Results Prolonging the harvest stage resulted in an increase in the levels of starch and dry matter as well as deoxynivalenol in corn silage. Addition of 1 × 107 cfu/g and 1 × 108 cfu/g of L. plantarum applied after 42 d of ensilage reduced dry matter loss, which significantly lowered deoxynivalenol concentration in corn silage at the dough stage (P

The gut microbiota establishment in young ruminants has a profound impact on their adult production performance. However, the critical phase for the succession of the gut microbial composition and metabolic profiles of juvenile sika deer still needs to be further investigated. Here, we analyzed the fecal microbiota and metabolites of juvenile sika deer during the birth (D1), transition (D42), and rumination (D70) periods based on 16S rRNA sequencing and gas chromatography–time–of–flight mass spectrometry (GC–TOF–MS). The results showed that the fecal bacteria and metabolites composition were significantly different in D1 compared to D42 and D70, and the number of OTUs and the Shannon index were significantly higher in D70 than in D1 (p < 0.05). The relative abundances of Lactobacillus, Lactococcus, and Lachnoclostridium showed a significant increase in D1 compared to D42 and D70, whereas the relative abundances of Ruminococcaceae UCG-005, Ruminococcaceae UCG-010, Ruminococcaceae UCG-014, Christensenellaceae R-7, and Eubacterium coprostanoligenes group were significantly decreased in D1 compared to D42 and D70 (p < 0.05). The amounts of serine, phenylalanine, aspartic acid, ornithine, citrulline, creatine, isoleucine, galactose, and ribose in the feces were significantly higher in D1 compared to D42 and D70. In contrast, the concentrations of cortexolone, resveratrol, piceatannol, fumaric acid, alpha-ketoglutarate, glycerol, uracil-5-carboxylic acid, and maleic acid were significantly decreased in D1. The enrichment analysis showed that amino acid metabolism and carbohydrate metabolism were significantly changed in D1 compared to D42 and D70. The glycine, serine and threonine metabolism; alanine, aspartate and glutamate metabolism; arginine biosynthesis; glyoxylate and dicarboxylate metabolism; citrate cycle; and pyruvate metabolism were significantly enriched across the three periods (p < 0.05). In conclusion, our results suggested that the birth–transition period is a critical phase for the gut bacterial community and metabolic function shift in juvenile sika deer.

Enteric methane (CH4) is an important greenhouse gas emitted by ruminants. Cervidae produces less CH4 than other ruminants, but the underlying mechanism remains unclear. Here, we measured and compared the gas production, nutrient digestibility, gut microbiota composition, and fermentation characteristics of roe deer (n = 4) and goats (n = 4). After the animals had adapted to the same total mixed ration for 21 days, the gas yield was measured using respiration chambers, and fecal samples were collected. The CH4 yield (g/kg DMI) was significantly lower in roe deer than in goats (p < 0.001), while the difference in carbon dioxide yield was not significant (p > 0.05). Roe deer showed lower digestibility of dry matter (p = 0.005), crude protein (p < 0.001), and neutral detergent fiber (p = 0.02) than goats. Principal coordinate analysis revealed that the bacterial and methanogen communities were significantly different between roe deer and goats, indicating a potential role of host genetics. Roe deer and goats showed enrichment of specific key bacterial and methanogen taxa. The relative abundances of Bifidobacterium, Ruminococcus, Succinivibrio, Treponema, Prevotella, Lachnoclostridium, Christensenellaceae R7, and members of the family Lachnospiraceae were higher in roe deer than in goats (p < 0.05). Methanocorpusculum and Methanobrevibacter were dominant methanogens in the guts of roe deer and goats, respectively, but their species compositions differed significantly between the host species. The predicted metabolic pathways, including those for butyrate and propionate, were significantly more abundant in roe deer than in goats (p < 0.05). The molar proportions of propionate and branched volatile fatty acids were significantly higher in roe deer and goats (p < 0.01), respectively. The variation in CH4 yield was characterized by correlations between digestibility, bacteria and methanogens between roe deer and goats, particularly for members within the taxa Lachnospiraceae and Methanosphaera. In summary, our results revealed that gut bacteria and methanogens differ significantly between high- and low-CH4 emitters and identified microbial taxa potentially involved in the mitigation of CH4 production in ruminants.

The level of plasma 25-hydroxyvitamin D (25(OH)D) is associated with the growth of the antler, a fast-growing bone organ of Cervidae. However, the benefits of 25(OH)D supplementation on antler growth and the underlying mechanisms remain unclear. Here, the antler growth profile and transcriptome, plasma parameters, rumen bacteria, and metabolites (volatile fatty acids and amino acids) were determined in sika deer in a 25(OH)D supplementation group (25(OH)D, n = 8) and a control group (Ctrl, n = 8). 25(OH)D supplementation significantly increased the antler weight and growth rate. The levels of IGF-1,25(OH)D and 1,25-dihydroxyvitamin D were significantly higher in the 25(OH)D group than in the Ctrl group, while the levels of LDL-C were lower. The levels of valerate and branched-chain amino acids in the rumen fluid were significantly different between the 25(OH)D and Ctrl groups. The bacterial diversity indices were not significantly different between the two groups. However, the relative abundances of the butyrate-producing bacteria (families Lachnospiraceae and Succinivibrionaceae) and the pyruvate metabolism pathway were higher in the 25(OH)D group. The transcriptomic profile of the antler was significantly different between the 25(OH)D and Ctrl groups, with 356 up- and 668 down-regulated differentially expressed genes (DEGs) in the 25(OH)D group. The up-regulated DEGs were enriched in the proteinaceous extracellular matrix and collagen, while the down-regulated DEGs were enriched in the immune system and lipid metabolism pathways. Overall, these results provide novel insights into the effects of 25(OH)D supplementation on the host metabolism, rumen microbiota, and antler transcriptome of sika deer.

Leaf area index (LAI) plays an important role in models of climate, hydrology, and ecosystem productivity. The physical model-based inversion method is a practical approach for large-scale LAI inversion. However, the ill-posed inversion problem, due to the limited constraint of inaccurate input parameters, is the dominant source of inversion errors. For instance, variables related to leaf optical properties are always set as constants or have large ranges, instead of the actual leaf reflectance of pixel vegetation in the current model-based inversions. This paper proposes to estimate LAI with the actual leaf optical property of pixels, calculated from the leaf chlorophyll content (Chlleaf) product, using a three-dimensional stochastic radiative transfer model (3D-RTM)-based, look-up table method. The parameter characterizing leaf optical properties in the 3D-RTM-based LAI inversion algorithm, single scattering albedo (SSA), is calculated with the Chlleaf product, instead of setting fixed values across a growing season. An algorithm to invert LAI with the dynamic SSA of the red band (SSAred) is proposed. The retrieval index (RI) increases from less than 42% to 100%, and the RMSE decreases to less than 0.28 in the simulations. The validation results show that the RMSE of the dynamic SSA decreases from 1.338 to 0.511, compared with the existing 3D-RTM-based LUT algorithm. The overestimation problem under high LAI conditions is reduced.

Co-substituted U-type hexagonal ferrite bulks, with composition of Ba4Ni2−xCoxFe36O60 (x=0.2, 0.4, 0.6, 0.8), were prepared by a conventional ceramic method. Saturation magnetization (4πMs), coercivity (Hc), and Curie temperature (Tc) were investigated. Anisotropy constant (K1) was calculated by fitting the magnetization curve (M-H) according to the law of approach to saturation, and anisotropy field (Ha) was calculated accordingly. The results reveal that all the samples possess the U-type hexagonal crystallographic structure. With increasing cobalt substitution content (x), the lattice parameters (a and c) almost remain the same owing to the similar radii of Ni2+ (0.72 Å) Co2+ (0.74 Å) ions. 4πMs goes up, while Hc Hc shows an opposite trend. K1 and Ha monotonously decrease resulting from that cobalt substitution weakens the c-axis orientation. Additionally, Tc increases from 467 °C to 484 °C.