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[Objective] In order to enrich the data for the study of micropyle closure in gymnosperms and to provide a reference for the phylogenetic study of gymnosperms, micropyle closure of Platycladus orientalis Franco was investigated. [Methods] Female cones of P . orientalis were sampled and examined using morphological techniques, including paraffin section and scanning electron microscopy. In addition, cluster analysis of the mode of micropyle closure was conducted for Bennettitales. [Results] (1) After pollen enters the ovule, the innermost two cell layers of the integument began to grow radially inward until the micropyle was completely closed. (2) During the micropyle closure, the innermost cells of the integument were elongated and became conical in shape, with the cell layers typically increased to 4 to 6 layers. (3) The micropyle closure of gymnosperms could be divided into four clades: One for Cycas and Ginkgo, one for Pinus and Podocarpaceae, a separate group for Bennettitales, and a cluster of P . orientalis and other species. [Conclusion] The micropyle closure of P . orientalis differs from Ginkgo and cycads, which is similar to Pinus and Bennettitales. This study suggests that there is an evolutionary relationship in micropyle closure between Bennettitales and existing conifers, providing novel morphological evidence for the understanding of evolution of the reproductive systems of gymnosperms.

The prevalence of myopia has markedly increased in East and Southeast Asia, and pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. Hence, strategies are warranted to reduce the prevalence of myopia and the progression to high myopia because this is the main modifiable risk factor for pathologic myopia. On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents. Useful clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops, in concentrations ranging between 0.01% and 0.05%, despite the side effects of a slightly reduced amplitude of accommodation, slight mydriasis, and risk of an allergic reaction; multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology using corneal gas-permeable contact lenses that are designed to flatten the central cornea, leading to midperipheral steeping and peripheral myopic defocus, during overnight wear to eliminate daytime myopia. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. The measures listed above are not mutually exclusive and are beginning to be examined in combination.

With the rapid development of economic levels, the demand for electricity usage in various industrial sectors has continued to rise. In order to adequately meet the growth in demand for electricity usage at each user end within the power system, accurate forecasting of electricity load is required. This paper uses the K-Means algorithm as the basis, combined with the Canopy algorithm, whose simple and efficient advantages can be used as the initial clustering step for demanding clustering algorithms. The PCA algorithm is used to reduce the dimensionality of the residential multidimensional electricity consumption feature set, and after optimization, the feature vector weights are calculated to obtain the appropriate selection to determine the training and testing samples. The improved K-Means algorithm carries out five clustering tests, and its average accuracy is above 97%. The average relative error is then used as an indicator to compare the algorithm with the time series method, curve extrapolation method, and WKNR method for analysis. The average relative error of the smart grid load forecasting method proposed in this paper is 0.87%, while the average relative errors of the other three algorithms are 1.64%, 1.57%, and 0.93%, respectively. The distribution of relative errors falls less than 1% more than the other methods. It can be seen that the improved K-Means algorithm has higher prediction accuracy and also makes the smart grid load testing platform more practical due to its simple implementation principle.

intraoperative hypothermia is a common complication in hepatectomy for liver cancer. This paper analyzed influencing factors of intraoperative hypothermia in hepatectomy for primary liver cancer, summarized nursing countermeasures, and provided reference for prevention of intraoperative hypothermia and its consequence in hepatectomy for primary liver cancer. (术中低体温是肝癌行肝切除术常见并发症。本研究分析导致肝癌行肝切除术术中低体温的相关因素, 总结护理干预措施, 以期为预防术中低体温以及降低术中低体温对肝癌患者造成的损伤提供参考。)