Explore the vast range of titles available.

This study aimed to investigate the effects of microbial inoculants (L) and molasses (M) on the bacterial and fungal microbiomes of barley silage after the aerobic stage. The addition of molasses and microbial inoculants improved the aerobic stability of barley silage. The ML silage, which had a low pH value and high lactic and acetic acid contents, remained aerobically stable for more than 216 h. The ML silage exhibited low bacterial and high fungal diversities. Microbial inoculants and molasses enriched the abundance of Lactobacillus in silage after aerobic exposure. The enrichment of L. buchneri was significant in ML silage at days 5 and 7 during the aerobic stage. The abundance of harmful microorganisms, such as aerobic bacterial including Acinetobacter , Providencia , Bacillus , and yeasts including Issatchenkia , Candida , and Kazachstania , were suppressed in ML silage. M and L had an impact on bacterial and fungal microbes, resulting in the improvement of fermentation quality and reduction of aerobic spoilage in barley silage.

In this article, a Nd2Fe14Bp/2024Al composite was prepared using high-energy ball milling, magnetic field cold isostatic pressing, and microwave sintering. The influence of powder particle size on microstructure and mechanical properties was discussed. The experimental results demonstrated that a ball milling duration of 10 h yielded powders with an average particle size of 5 μm, resulting in a refined and homogeneous microstructure, with a hardness value of 115 HV. Additionally, the densification process of the microwave-sintered sample was analyzed. When the sintering temperature was 490 °C, in-depth analysis was conducted on the effect of Nd2Fe14B addition on the microstructure and properties of the composite. The results showed that when the addition of Nd2Fe14B was 15 wt.%, the microstructure of the composite was uniform with fewer pores, and the Nd2Fe14B phase was evenly distributed on the matrix. At the same time, the compactness, microhardness, yield strength, and compressive strength of the composite also reached their optimal values, which were 94.3%, 136 HV, 190.5 MPa, and 248.9 MPa, respectively. When the addition of Nd2Fe14B reached 20 wt.%, the magnetic properties of the composite were slightly better than those of 15 wt.% Nd2Fe14B addition. However, based on the goal of preparing a high-magnetic and high-performance aluminum-based composite, considering the microstructure, mechanical properties, and magnetic properties comprehensively, it is believed that 15 wt.% is the optimal addition amount of Nd2Fe14B.

In micro-production technology (MPT), the demand for ultra-precise machine tools has been steadily increasing. Conventional guideway systems, such as hydrostatic or aerostatic bearings, often face limitations in terms of compactness, media supply, and susceptibility to external disturbances, which restrict their applicability in next-generation precision manufacturing. In order to address these challenges, this paper presents a novel media-free, contactless, and active three-degree-of-freedom (DOF) planar positioning (guiding) system that integrates ultrasonic actuators with electromagnetic actuators. The hybrid concept combines the high load capacity and self-stabilization of double-acting ultrasonic actuators and pronounced controllability of the electromagnetic actuators. A prototype system was developed and experimentally validated. Ultrasonic actuators successfully established a stable levitation state, while electromagnetic actuators provided fine adjustment of the levitation height in the micrometer range. Load tests demonstrated that the system maintained stable levitation under an external load of 30 N. These results confirm the feasibility of the proposed approach for robust and precise positioning. The developed hybrid system therefore represents the potential for next-generation precise manufacturing machines in MPT, offering high accuracy and robustness against external disturbances.

Microelectromechanical systems (MEMSs) are increasingly used for both industrial and consumer applications. To improve the accuracy and efficiency of MEMS fabrication and to overcome the limitations of conventional contactless positioning systems, this study introduces a novel positioning concept that combines ultrasonic levitation with electromagnetic actuation. Squeeze-film effects generated by high-frequency ultrasonic transducers enable levitation, while fast-response reluctance forces from electromagnets govern the positioning dynamics without requiring bulky mounting frames. The focus of this paper is on proposing a novel double-acting ultrasonic transducer with a Gaussian profile horn, ensuring an approximately uniform vibration distribution and increased levitation force. The double-acting design enables levitation on both surfaces, simplifying the mounting and thermal compensation of the transducer’s expansion while reducing interactions among transducers. A model-based control strategy ensures resonant operation and constant vibration amplitude. Experiments demonstrate levitation forces up to 343 N, with a total levitation height of 25 µm, resulting from two levitation air gaps. Comprehensive performance characterization validates the feasibility of this transducer design for integration into the proposed positioning system.

In order to study surface roughness, surface morphology, surface microhardness, and surface residual stress, single-factor and central combination high-speed milling testing of SiCp/Al composites was carried out using a PCD tool under cryogenic liquid nitrogen cooling conditions. The test results show that the surface roughness value gradually increases with an increase in feed or milling depth, and the interaction between the two can make this phenomenon more serious. When the milling speed changes at 200~360 m/min, the surface microhardness and surface residual stress first increase, and then, become smaller, so it is recommended to use a speed above 240 m/min for milling under cryogenic liquid nitrogen cooling conditions. With an increase in milling depth and feed, the degree of surface microhardness is significantly improved, and the residual compressive stress also has a tendency to convert to residual tensile stress. In addition, it can be seen from the simulation results that as the milling depth and feed per tooth increase, the interference effect of the SiC particles on internal residual stress transfer also increases. Therefore, it is not recommended to use both high milling depths and high feed per tooth.

BackgroundThis study aimed to evaluate the ensiling characteristics, bacterial community structure, co-occurrence networks, and their predicted functionality and pathogenic risk in high-moisture oat (Avena sativa L.) silage. The oat harvested at heading stage (224 g/kg fresh weight) was spontaneously ensiled in plastic silos (10 L scale). Triplicate silos were opened after 1, 3, 7, 15, 30 and 60 days of fermentation, respectively. The bacterial community structure on day 3 and 60 were investigated using high-throughput sequencing technology, and 16S rRNA-gene predicted functionality and phenotypes were determined by PICRUSt2 and BugBase tools, respectively.ResultsAfter 60 days, the oat silage exhibited moderate fermentation quality, as indicated by large amounts of acetic acid (~ 50.4 g/kg dry matter (DM)) and lactic acid (~ 55.4 g/kg DM), relatively high pH (~ 4.79), acceptable levels of ammonia nitrogen (~ 75.2 g/kg total nitrogen) and trace amounts of butyric acid (~ 3.36 g/kg DM). Psychrobacter was prevalent in fresh oat, and Enterobacteriaceae and Lactobacillus dominated the bacterial community on day 3 and 60. Ensilage reduced the complexity of bacterial community network at the initial stage of fermentation. The bacterial functional pathways in fresh and ensiled oat are primarily characterized by the metabolism of carbohydrate and amino acid. During ensiling, the elevated pyruvate kinase and 1-phosphofructokinase levels were correlated with the lactic acid production, and the increased levels of 6-phosphogluconate dehydrogenase and ribulose-5-phosphate 3-epimerase may be responsible for the abundant acetic acid contents. Greater (P < 0.01) proportions of “Potentially Pathogenic” were observed in the bacterial community of oat silage compared to fresh oat.ConclusionsAltogether, the findings indicated that the high-moisture oat silage exhibited moderate fermentation quality, and the potential for microbial contamination and pathogens remained after 60 days of ensiling. Therefore, some effective chemical and microbial additives are recommended to ensure the quality, hygiene, and safety in high-moisture oat silage production.

Objective: The objective of this study was to evaluate the effect of biogas slurry application on biomass production and the silage quality of corn.Methods: A field experiment was conducted in which corn was grown using different biogas slurry application rates. The effect of 25% to 500% biogas slurry nitrogen replacement (T1 to T14) on the yield and quality indices of corn were studied by field plot experiments.Results: The results revealed that biogas slurry application improved the stem diameter and relative feed value of corn silage in treatments T13 and T11. Moreover, the fermentation quality of corn silage was improved due to an increase in lactic acid content; in comparison with the chemical synthetic fertilizer (CF) group. The crude protein contents of corn silage had no obvious change with increasing biogas slurry application. However, the forage quality index of acid detergent fiber was decreased (p<0.05) in the T11 group compared with the CF group. In addition, higher (p<0.05) 30 h in vitro dry matter digestibility and 30 h in vitro neutral detergent fiber digestibility were observed in the T11 and T13 groups than in the CF group.Conclusion: Based on these results, it was concluded that the optimum biogas slurry application rate for corn was approximately 350% to 450% biogas slurry nitrogen replacement under the present experimental conditions.

This study aimed to assess the fermentation characteristics, bacterial community structure, co-occurrence networks, and their predicted functionality and pathogenic risk in high-moisture Italian ryegrass (IR; Lolium multiflorum Lam.) silage. The IR harvested at heading stage (208 g dry matter (DM)/kg fresh weight) was spontaneously ensiled in plastic silos (10 L scale). Triplicated silos were opened after 1, 3, 7, 15, 30, and 60 days of fermentation, respectively. The bacterial community structure on days 3 and 60 were investigated using high-throughput sequencing technology, and 16S rRNA-gene predicted functionality and phenotypes were determined by PICRUSt2 and BugBase tools, respectively. After 60 days, the IR silage exhibited good ensiling characteristics indicated by large amounts of acetic acid (~58.7 g/kg DM) and lactic acid (~91.5 g/kg DM), relatively low pH (~4.20), acceptable levels of ammonia nitrogen (~87.0 g/kg total nitrogen), and trace amounts of butyric acid (~1.59 g/kg DM). Psychrobacter was prevalent in fresh IR, and Lactobacillus became the most predominant genus after 3 and 60 days. The ensilage process reduced the complexity of the bacterial community networks in IR silage. The bacterial functional pathways in fresh and ensilaged IR are primarily characterized by the metabolism of carbohydrate and amino acid. The pyruvate kinase and 1-phosphofructokinase were critical in promoting lactic acid fermentation. A greater (p < 0.01) abundance of the “potentially pathogenic” label was noticed in the bacterial communities of ensiled IR than fresh IR. Altogether, the findings indicated that the high-moisture IR silage exhibited good ensiling characteristics, but the potential for microbial contamination and pathogens still remained after ensiling.

To assess the genetic diversity and population structure of species, we used 32 nuclear simple sequence repeat (SSR) markers and 7 cytoplasmic gene markers to analyze a total of 357 individuals from 162 accessions of 9 species. This survey revealed a high level of polymorphism, with an average number of alleles per locus of 23.59 and 5.29 and an average PIC-value of 0.83 and 0.54 for nuclear SSR markers and cytoplasmic gene markers, respectively. Analysis of molecular variance (AMOVA) revealed that 16.27 and 16.53% of the total variation was due to differences among species, with the remaining 56.35 and 83.47% due to differences within species and 27.39 and 0% due to differences within individuals in 32 nuclear SSR markers set and 6 chloroplast gene markers set, respectively. The 32 nuclear SSR markers detected three subpopulations among 357 individuals, whereas the 6 chloroplast gene markers revealed three subpopulations among 160 accessions in the STRUCTURE analysis. In the clustering analysis, the three inbred species clustered into a single group, whereas the outbreeding species were clearly divided, especially according to nuclear SSR markers. In addition, almost all populations were clustered into group C4, which could be further divided into three subgroups, whereas populations primarily clustered into two groups (C2 and C3), with a few lines that instead grouped with (C4) or (C6). Together, these results will useful for the use of germplasm for improvement and increase the effectiveness of ryegrass breeding.

Lung cancer is the most common type of malignant tumor worldwide. Plasma-activated medium (PAM) is an innovative cancer treatment method that has received considerable scientific attention. The objective of this study is to evaluate the effects of PAM on the anti-tumor characteristics of non-small cell lung cancer (NSCLC) cells in two-dimensional (2D) and three-dimensional (3D) cultures. The effects of PAM treatment on the proliferative and migratory capabilities of A549 cells in 2D and 3D cultures were assessed using MTT, migration, invasion assays, and cell cycle, respectively. The study also investigated the impact of PAM treatment on the changes in the content of intracellular and extracellular reactive species and analyzed protein expression using the Western Blot method. PAM treatment inhibited the viability, migration, and invasion abilities of A549 cells in both 2D and 3D cultures, suppressed the epithelial–mesenchymal transition (EMT) process, and downregulated the expression of the RAS/ERK signaling pathway, which effectively inhibited tumor spheroid formation. Additionally, the effect of PAM on A549 cells was mediated through ROS-induced oxidative reactions, and PAM treatment exhibited greater cytotoxicity in 2D culture compared to 3D culture. As compared to 2D, the 3D cell culture model provides a viable in vitro cell model for studying the mechanisms of PAM treatment in lung cancer. PAM represents an effective new treatment for NSCLC.