20 research outputs found

    Synthesis of the System Modeling and Signal Detecting Circuit of a Novel Vacuum Microelectronic Accelerometer

    Get PDF
    A novel high-precision vacuum microelectronic accelerometer has been successfully fabricated and tested in our laboratory. This accelerometer has unique advantages of high sensitivity, fast response, and anti-radiation stability. It is a prototype intended for navigation applications and is required to feature micro-g resolution. This paper briefly describes the structure and working principle of our vacuum microelectronic accelerometer, and the mathematical model is also established. The performances of the accelerometer system are discussed after Matlab modeling. The results show that, the dynamic response of the accelerometer system is significantly improved by choosing appropriate parameters of signal detecting circuit, and the signal detecting circuit is designed. In order to attain good linearity and performance, the closed-loop control mode is adopted. Weak current detection technology is studied, and integral T-style feedback network is used in I/V conversion, which will eliminate high-frequency noise at the front of the circuit. According to the modeling parameters, the low-pass filter is designed. This circuit is simple, reliable, and has high precision. Experiments are done and the results show that the vacuum microelectronic accelerometer exhibits good linearity over -1 g to +1 g, an output sensitivity of 543 mV/g, and a nonlinearity of 0.94 %

    Exploring the effects of lysozyme dietary supplementation on laying hens: performance, egg quality, and immune response

    Get PDF
    An experiment was conducted to evaluate the dietary supplementation with lysozyme's impacts on laying performance, egg quality, biochemical analysis, body immunity, and intestinal morphology. A total of 720 Jingfen No. 1 laying hens (53 weeks old) were randomly assigned into five groups, with six replicates in each group and 24 hens per replicate. The basal diet was administered to the laying hens in the control group, and it was supplemented with 100, 200, 300, or 400 mg/kg of lysozyme (purity of 10% and an enzyme activity of 3,110 U/mg) for other groups. The preliminary observation of the laying rate lasted for 4 weeks, and the experimental period lasted for 8 weeks. The findings demonstrated that lysozyme might enhance production performance by lowering the rate of sand-shelled eggs (P < 0.05), particularly 200 and 300 mg/kg compared with the control group. Lysozyme did not show any negative effect on egg quality or the health of laying hens (P > 0.05). Lysozyme administration in the diet could improve intestinal morphology, immune efficiency, and nutritional digestibility in laying hens when compared with the control group (P < 0.05). These observations showed that lysozyme is safe to use as a feed supplement for the production of laying hens. Dietary supplementation with 200 to 300 mg/kg lysozyme should be suggested to farmers as a proper level of feed additive in laying hens breeding

    Roadmap on superoscillations

    Get PDF
    Superoscillations are band-limited functions with the counterintuitive property that they can vary arbitrarily faster than their fastest Fourier component, over arbitrarily long intervals. Modern studies originated in quantum theory, but there were anticipations in radar and optics. The mathematical understanding—still being explored—recognises that functions are extremely small where they superoscillate; this has implications for information theory. Applications to optical vortices, sub-wavelength microscopy and related areas of nanoscience are now moving from the theoretical and the demonstrative to the practical. This Roadmap surveys all these areas, providing background, current research, and anticipating future developments

    Roadmap on Superoscillations

    Get PDF
    Superoscillations are band-limited functions with the counterintuitive property that they can vary arbitrarily faster than their fastest Fourier component, over arbitrarily long intervals. Modern studies originated in quantum theory, but there were anticipations in radar and optics. The mathematical understanding—still being explored—recognises that functions are extremely small where they superoscillate; this has implications for information theory. Applications to optical vortices, sub-wavelength microscopy and related areas of nanoscience are now moving from the theoretical and the demonstrative to the practical. This Roadmap surveys all these areas, providing background, current research, and anticipating future developments

    Deep Sub–Wavelength Focusing Metalens at Terahertz Frequency

    No full text
    With the benefits of non–invasive and low radiation, terahertz radiation has shown great potential in biomedical imaging applications. However, the low spatial resolution of the imaging system significantly affects its application in these fields. Although immersion techniques and super–oscillation theory have achieved considerable success in improving the resolution of imaging systems, there are still problems with large focal spot sizes or large sidebands. Herein, a solid immersion lens based on super–oscillation is proposed to reduce the focal spot size when illuminated with circularly polarized light at a wavelength of 118.8 μm. The simulation results show that the lens can compress the full widths at half–maxima down to deep sub–wavelength scales, as small as 0.232 λ. At the same time, the maximum side–lobe ratio was 16.8%, which ensured that the device had a large field of view. The proposed method reveals new ideas in the field of super–resolution imaging

    Fabrication of Si-PDMS Low Voltage Capillary Electrophoresis Chip

    No full text

    Silencing USP19 alleviates cigarette smoke extract-induced mitochondrial dysfunction in BEAS-2B cells by targeting FUNDC1

    No full text
    Chronic obstructive pulmonary disease (COPD) is commonly caused by smoking. FUN14 domain-containing protein 1 (FUNDC1) plays a fundamental role in mitochondrial autophagy and apoptosis in cigarette smoke extract (CSE)-treated BEAS-2B cells. The present study investigated the mechanism of action of FUNDC1 in mitochondrial dysfunction and apoptosis in CSE-treated BEAS-2B cells. The interaction between ubiquitin-specific peptidase 19 (USP19) and FUNDC1 was analyzed using co-immunoprecipitation. Effects of USP19 knockdown and/or FUNDC1 overexpression on the survival, apoptosis, mitochondrial membrane potential, and oxygen consumption rate (OCR) of BEAS-2B cells treated with 15% CSE were determined. In BEAS-2B cells, CSE inhibited cell survival, promoted apoptosis, increased the expression of USP19 and FUNDC1, increased the ratio of LC3 II to LC3 I (LC3 II/I), and decreased mitochondrial membrane potential and TOM20 levels. In CSE-treated BEAS-2B cells, USP19 knockdown reduced FUNDC1 and LC3 II/I, increased the levels of TOM20, improved cell survival, mitochondrial membrane potential, and OCR, and inhibited apoptosis. USP19 deubiquitinates FUNDC1. FUNDC1 overexpression inhibited the effect of USP19 knockdown in CSE-treated BEAS-2B cells. Overall, decreasing USP19 expression alleviates CSE-induced mitochondrial dysfunction in BEAS-2B cells by downregulating FUNDC1, providing novel insights into the molecular mechanism of FUNDC1 regulation in COPD

    Abrupt Dietary Change and Gradual Dietary Transition Impact Diarrheal Symptoms, Fecal Fermentation Characteristics, Microbiota, and Metabolic Profile in Healthy Puppies

    No full text
    Dietary changes are inevitable for pets, yet little is known about the impact of different dietary change methods on the gastrointestinal response. The current comparative study evaluated the effects of different dietary changes on the diarrheal symptoms, fecal fermentation characteristics, microbiota, and metabolic profile of healthy puppies. A total of 13 beagle puppies were randomly divided into two groups; puppies in the abrupt change (AC) group were given 260 g of a chicken- and duck-based extruded diet (CD)daily for the one-week transition period, whereas puppies in the gradual transition (GT) group were fed according to a gradual transition ratio of a salmon-based extruded diet (SA) and a CD diets with a difference of 40 g per day for seven consecutive days. Serum samples were collected on D7, and fecal samples were collected on D0 and D7. The results indicated that GT reduced the incidence of diarrhea in puppies throughout the trial period. Dietary change methods had no influence on serum inflammatory factors or fecal SCFAs, but isovaleric acid was significantly reduced after GT. Meanwhile, 16S rRNA sequencing showed that the fecal microbiota was changed after different dietary changes. Compared with the bacterial changes after AC, the relative abundances of beneficial bacteria (i.e., Turicibacter and Faecalibacterium) in feces were increased after GT in puppies. Additionally, both GT and AC caused changes in amino acid metabolism, while AC also altered lipid metabolism. AC increased fecal histamine and spermine concentrations, but decreased concentrations of metabolites such as 5-hydroxyindoleacetic acid and serotonin. Our findings indicated that GT most likely reduced the diarrhea rate in puppies by modulating the composition and metabolism of the gut microbiota

    Effects of Softening Dry Food with Water on Stress Response, Intestinal Microbiome, and Metabolic Profile in Beagle Dogs

    No full text
    Softening dry food with water is believed to be more beneficial to the intestinal health and nutrients absorption of dogs by some owners, but there appears to be little scientific basis for this belief. Thus, this study aimed to compare feeding dry food (DF) and water-softened dry food (SDF) on stress response, intestinal microbiome, and metabolic profile in dogs. Twenty healthy 5-month-old beagle dogs were selected and divided into two groups according to their gender and body weight using a completely randomized block design. Both groups were fed the same basal diet, with one group fed DF and the other fed SDF. The trial lasted for 21 days. The apparent total tract digestibility (ATTD) of nutrients, inflammatory cytokines, stress hormones, heat shock protein-70 (HSP-70), fecal microbiota, short-chain fatty acids (SCFAs), branch-chain fatty acids (BCFAs), and metabolomics were measured. Results showed that there was no significant difference in body weight, ATTD, and SCFAs between the DF and SDF groups (p > 0.05), whereas feeding with SDF caused a significant increase in serum cortisol level (p p = 0.062) and HSP-70 (p = 0.097) levels. Fecal 16S rRNA gene sequencing found that the SDF group had higher alpha diversity indices (p Streptococcus, Enterococcus, and Escherichia_Shigella, and lower levels of Faecalibacterium (p p < 0.05). Overall, feeding with SDF caused higher cortisol level and generated effects of higher intestinal microbial diversity in dogs, but it caused an increase in some pathogenic bacteria, which may result in intestinal microbiome disturbance and metabolic disorder in dogs. In conclusion, feeding with SDF did not provide digestive benefits but caused some stress and posed a potential threat to the intestinal health of dogs. Thus, SDF is not recommended in the feeding of dogs
    corecore