2,511 research outputs found

    Calorific values and ash contents of different organs of Masson pine (Pinus massoniana) in southern China

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    Calorific values of plants are important indices for evaluating and reflecting material cycle and energy conversion in forest ecosystems. Based on the data of Masson Pine (Pinus massoniana) in southern China, the calorific values (CVs) and ash contents (ACs) of different plant organs were analyzed systematically using hypothesis test and regression analysis in this paper. The results show: (i) the CVs and ACs of different plant organs are almost significantly different, and the order by AFCV (ash-free calorific value) from the largest to the smallest is foliage (23.55 kJ/g), branches (22.25 kJ/g), stem bark (21.71 kJ/g), root (21.52 kJ/g) and stem wood (21.35 kJ/g); and the order by AC is foliage (2.35%), stem bark (1.44%), root (1.42%), branches (1.08%) and stem wood (0.33%); (ii) the CVs and ACs of stem woods on top, middle and lower sections are significantly different, and the CVs are increasing from top to lower sections of trunk while the ACs are decreasing; (iii) the mean GCV (gross calorific value) and AFCV of aboveground part are larger than those of belowground part (roots), and the differences are also statistically significant; (iv) the CVs and ACs of different organs are related, to some extent, to diameter, height and origin of the tree, but the influence degrees of the factors on CVs and ACs are not the same

    Long-term results of clear lens extraction combined with piggyback intraocular lens implantation to correct high hyperopia

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    <b>AIM:</b> To assess the refractive outcome of clear lensectomy combined with piggyback intraocular lens implantation in highly hyperopic patients.<b>METHODS:</b> This case review included 19 eyes of 10 patients with high hyperopia and axial length less than 21mm. Intraocular lens power was calculated for emmetropia using the Holladay II formula in 17 eyes, and SRK/T formula in 2 eyes following clear lens extraction and piggyback intraocular lens implantation. Patients were examined periodically over 24 months for visual acuity and spherical equivalent (SE).<b>RESULTS:</b> The mean postoperative SE at 24 months was 0.20±1.39D (range, -3.00 to 2.50D), better than preoperative 9.81±2.62D (range, +6.00 to +14.50D) (<i>P</i><0.001). Five eyes had SE within ±0.5D of emmetropia and 11 eyes within ±1.00D at postoperative 24 months. The mean postoperative uncorrected visual acuity (UCVA) at 24 months was 0.60±0.36, significantly improved compared to preoperative 1.39±0.33 (<i>P</i><0.001). The mean best-corrected visual acuity (BCVA) at 24 months was 0.49±0.35, not statistically different compared to preoperative 0.38±0.30 (<i>P</i>=0.34). Twelve eyes maintained and 1 gained 1 or more Snellen line of BCVA, 4 eyes lost 1 line, and 2 eyes lost 2 lines at 24 postoperative months. Twelve eyes best-corrected near visual acuity (BCNVA) achieved J1 at postoperative 24 months compared to preoperative 7 eyes and the other 7 eyes better than J3.<b>CONCLUSION:</b> Clear lens extraction combined piggyback intraocular lens implantation appears to be an effective procedure to correct high hyperopia but mild overcorrection and intralenticular opacification may require secondary procedure

    Potential of Constraining Propagation Parameters of Galactic Cosmic Rays with the High Energy cosmic-Radiation Detection facility onboard China's Space Station

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    Precise measurements of the spectra of secondary and primary cosmic rays are crucial for understanding the origin and propagation of those energetic particles. The High Energy cosmic-Radiation Detection (HERD) facility onboard China`s Space Station, which is expected to operate in 2027, will push the direct measurements of cosmic ray fluxes precisely up to PeV energies. In this work, we investigate the potential of HERD on studying the propagation of cosmic rays using the measurements of boron, carbon, and oxygen spectra. We find that, compared with the current results, the new HERD measurements can improve the accuracy of the propagation parameters by 8\% to 40\%. The constraints on the injection spectra at high energies will also be improved.Comment: 10 pages, 4 figure

    The use of selected bacteria and yeasts to control vibrio spp. in live food

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    Vibrio species are a significant causative of mass mortality in mariculture worldwide, which can quickly accumulate in live food and transmit into the larval gut. With restrictions on the use of antibiotics in aquaculture, finding a proper solution to reduce the risk of Vibriosis is vital. This study aimed to evaluate the susceptibility of Vibrio harveyi, V. campbellii, V. anguillarum, and V. parahaemolyticus to twenty-six bacterial and yeast strains and use the beneficial ones to enrich live food (Branchiopod, Artemia franciscana, rotifer, Brachionus plicatilis and copepod, Tigriopus japonicus). Thus, a modified disk diffusion method was applied. After a susceptibility assay, the bacteria and yeast beneficial in suppressing the Vibrio species were labeled by fluorescent stain and used to measure the accumulation potential in different live foods. Also, the beneficial bacteria and yeast were used to enrich live foods, and then the count of loaded Vibrio was estimated after 5, 10, 15, and 20 h by the serial dilution method. From the total bacteria and yeast strains that were used, Candida parapsilosis, Pseudoalteromonas flavipulchra, Lactobacillus sakei, Bacillus natto, and B. amyloliquefaciens inhibited all four Vibrio species. The results of microbial labeling showed that L. sakei in Artemia, C. parapsilosis in rotifers, and V. harveyi in copepods had the highest accumulation rate. The results of the estimation of loaded Vibrio in different live foods also showed that the use of beneficial bacteria and yeast each significantly reduced the count of Vibrio. Application of bacteria and yeast to suppress pathogenic Vibrio maybe a sustainable method for preventing this pathogen from harmfully invading aquaculture and may also aid in reducing the chances of antibiotic resistance in pathogenic Vibrio
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