52 research outputs found

    Enhanced photocatalytic reduction of carbon dioxide in optical fiber monolith reactor with transparent glass balls

    Get PDF
    Photocatalytic reduction of carbon dioxide to produce methanol is a promising approach to restrain greenhouse gases emissions and mitigate energy shortage, which attracts extensive concerns in recent years. The optical fiber monolith reactor with solid glass balls for photocatalytic carbon dioxide reduction is proposed in this work to increase the product concentration, and the glass balls are transparent and coated with photocatalysts evenly to absorb light. The photocatalytic reduction of carbon dioxide in optical fiber monolith reactor is numerically investigated, by which the effects of glass ball number, location, circle and layer on the production are analyzed. The results show that in the single-circle and single-layer model, the outlet methanol concentration increases with increasing the ball number. The closer to the fiber and reactor inlet the balls keep, the higher the methanol production is. As the circle and layer numbers increase, the methanol concentration also increases. The outlet methanol average concentration of the optical fiber monolith reactor with 3-circle and 5-layer balls gets 11.43% higher than the case without glass balls

    Memory-enhancing effect of Rhodiola rosea L extract on aged mice

    Get PDF
    Purpose: The memory-enhancing effects of Rhodiola rosea L. extract (RRLE) on normal aged mice were assessed.Methods: In the open-field test, the effect of RRLE (150 and 300 mg/kg) on mouse locomotive activities was evaluated by investigating the extract’s influence on CAT and AchE activities in the brain tissue of mice.Results: Compared with aged group, high dose of RRLE reduced the total distance (3212.4 ± 123.1 cm, p < 0.05) significantly, increased catalase (CAT) activity (101.4 ± 12.2 U/mg pro, p < 0.05), and inhibited acetyl cholinesterase (AChE) activity (0.94 ± 0.12 U/mg pro, p < 0.05) in the brain tissue of aged mice.Conclusion: The results show that RRLE improves the memory functions of aged mice probably by increasing CAT activity while decreasing AChE activity.Keywords: Rhodiola rosea, Memory function, Catalase, Acetyl cholinesterase, Open-field tes

    Efficacy of early prone or lateral positioning in patients with severe COVID-19: a single-center prospective cohort

    Get PDF
    Abstract Background Position intervention has been shown to improve oxygenation, but its role in non-invasively ventilated patients with severe COVID-19 has not been assessed. The objective of this study was to investigate the efficacy of early position intervention on non-invasively ventilated patients with severe COVID-19. Methods This was a single-center, prospective observational study in consecutive patients with severe COVID-19 managed in a provisional ICU at Renmin Hospital of Wuhan University from 31 January to 15 February 2020. Patients with chest CT showing exudation or consolidation in bilateral peripheral and posterior parts of the lungs were included. Early position intervention (prone or lateral) was commenced for &amp;gt; 4 hours daily for 10 days in these patients, while others received standard care. Results The baseline parameters were comparable between the position intervention group (n = 17) and the standard care group (n = 35). Position intervention was well-tolerated and increased cumulative adjusted mean difference of SpO2/FiO2 (409, 95% CI 86 to 733) and ROX index (26, 95% CI 9 to 43) with decreased Borg scale (−9, 95% CI −15 to −3) during the first 7 days. It also facilitated absorption of lung lesions and reduced the proportion of patients with high National Early Warning Score 2 (≥ 7) on days 7 and 14, with a trend toward faster clinical improvement. Virus shedding and length of hospital stay were comparable between the two groups. Conclusions This study provides the first evidence for improved oxygenation and lung lesion absorption using early position intervention in non-invasively ventilated patients with severe COVID-19, and warrants further randomized trials. </jats:sec

    The genome sequence of the orchid Phalaenopsis equestris

    Get PDF
    Orchidaceae, renowned for its spectacular flowers and other reproductive and ecological adaptations, is one of the most diverse plant families. Here we present the genome sequence of the tropical epiphytic orchid Phalaenopsis equestris, a frequently used parent species for orchid breeding. P. equestris is the first plant with crassulacean acid metabolism (CAM) for which the genome has been sequenced. Our assembled genome contains 29,431 predicted protein-coding genes. We find that contigs likely to be underassembled, owing to heterozygosity, are enriched for genes that might be involved in self-incompatibility pathways. We find evidence for an orchid-specific paleopolyploidy event that preceded the radiation of most orchid clades, and our results suggest that gene duplication might have contributed to the evolution of CAM photosynthesis in P. equestris. Finally, we find expanded and diversified families of MADS-box C/D-class, B-class AP3 and AGL6-class genes, which might contribute to the highly specialized morphology of orchid flowers. (Résumé d'auteur

    Ginkgo biloba Extract in Alzheimer’s Disease: From Action Mechanisms to Medical Practice

    Get PDF
    Standardized extract from the leaves of the Ginkgo biloba tree, labeled EGb761, is one of the most popular herbal supplements. Numerous preclinical studies have shown the neuroprotective effects of EGb761 and support the notion that it may be effective in the treatment and prevention of neurodegenerative disorders such as Alzheimer’s disease (AD). Despite the preclinical promise, the clinical efficacy of this drug remains elusive. In this review, possible mechanisms underlying neuroprotective actions of EGb761 are described in detail, together with a brief discussion of the problem of studying this herb clinically to verify its efficacy in the treatment and prevention of AD. Moreover, various parameters e.g., the dosage and the permeability of the blood brain barrier (BBB), impacting the outcome of the clinical effectiveness of the extract are also discussed. Overall, the findings summarized in this review suggest that, a better understanding of the neuroprotective mechanisms of EGb761 may contribute to better understanding of the effectiveness and complexity of this herb and may also be helpful for design of therapeutic strategies in future clinical practice. Therefore, in future clinical studies, different factors that could interfere with the effect of EGb761 should be considered

    Fluid Characteristics Analysis of the Lubricating Oil Film and the Wear Experiment Investigation of the Sliding Bearing

    No full text
    The sliding bearing is an important component in machines. The characteristics of the oil film fluid of the sliding bearing is the key factor affecting lubrication, which will affect the wear and reliability of the sliding bearing. Herein, the lubricating oil of the sliding bearing is studied, the oil film flow model considering the cavitation effect is established, the pressure and temperature distribution of the oil film under different rotational speeds is explored, and its influence on oil film pressure and temperature are analyzed. Furthermore, wear tests are carried out to measure the wear amount of the bearing bush under different rotational speeds, and the influence of the fluid characteristics of the lubricating oil film on bearing wear is explored. The simulation and experimental study in this paper can provide a reference for the design of sliding bearings

    Development of Subsea Pipeline Buckling, Corrosion and Leakage Monitoring

    No full text
    Oil and gas exploration is a sector which drives the global economy and currently contributes significantly to global economic development. The safety of subsea pipelines is deeply affected by factors such as pipeline buckling, corrosion and leakage. Once a subsea pipeline is seriously leaking or damaged, it will cause a lot of waste of resources at light level, and it will cause explosions in severe cases, resulting in heavy casualties and huge economic losses, and at the same time, seriously damaging the surrounding ecological environment. Therefore, it is necessary to pay attention to problems related to the buckling, corrosion and leakage of submarine pipelines. This paper consists of a literature review of the latest research about buckling, corrosion and leak detection
    corecore