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411.
针对传统旅游业服务模式无法跟进新的旅游发展态势的现状,依托移动增强现实、手绘地图智能导游、全景虚拟漫游、无人机航摄等技术.探索出一套集旅游信息发布、系统开发、运营管理和市场推广于一身的一体化、信息化、智能化的解决方案.以桂平市全域旅游建设为例.提出了全域旅游智慧化平台的构建模式,成果表现形式为桂平旅游门户网站、桂平旅游微信公众号、旅游wap商城、易游桂平APP、智能信息发布系统等,可以满足广大游客的旅游公共服务需求,对桂平市旅游的发展具有积极意义. 相似文献
412.
针对T形槽轨平顺度的测量、分析与调整方法进行了研究,旨在解决T形槽轨建设中难以对其平顺度进行检测和分析的问题采用自由测站测量技术在管内构建高精度三维控制网.解决了因管内环境条件限制而难以建立测量基准的问题;基于此控制网,釆用自由设站测呈与极坐标测址法相结合的技术测得槽轨上各测点的三维坐标,为槽轨平顺度的分析提供了基础数据;为对槽轨平顺度质量进行判定,运用统计分析方法将槽轨上各测点的偏差悄况量化为4项统计指标.结果表明选用的4项指标能够定量和全面地反映槽轨平顺度质量;为提高槽轨平顺度,提出了基于槽轨上各测点的偏差计算调整量和据此对槽轨进行精调的方法.结果表明该方法能显著提高槽轨平顺度。 相似文献
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Thyroid hormone is a kind of important hormone which regulates metamorphosis. Its role is well described in amphibian metamorphosis. Thyroid hormones (T3 and T4) have also been demonstrated to play a role in metamorphosis of marine invertebrates. However, the mechanism of thyroid hormone in metamorphosis of marine invertebrates remains unknown. A homolog of vertebrate thyroid hormone receptor (TR) was cloned and identified in abalone Haliotis diversicolor and was named HdTR . The mRNA expressions of HdTR , thyroid peroxidase ( TPO ), thyroid peroxidase 1 ( TPO1 ), idothyronine deiodinase Ⅲ( IDⅢ) and integrin alpha-V ( ITGAV ) had significant diff erence in metamorphosis of H . diversicolor . Metamorphosis rate and mortality rate were significantly diff erent in HdTR RNAi experiment and T3 inducing experiment. In RNAi experiment, ITGAV and CCND1 (cyclin D1) expression of dsRNA HdTR exposing group were significantly lower than those of blank control and negative control. But CTNNB (catenin beta) expression of dsRNA HdTR exposing group was higher than that those of blank control and negative control. ERK (extracellular signal regulated kinases) and PI3K (phosphoinositide-3-kinase) had no significant diff erence in RNAi experiment. Moreover, ITGAV of 1 μmol/L T3 group was significantly lower than that of 0 μmol/L T3 group, PI3K expression of 10 μmol/L T3 group was higher than that of 0 μmol/L T3 group, and the other genes expression had no significant diff erence in T3 inducing experiment. The data of genes expression suggested that CCND1 might be an eff ector gene of TR genomic action, while CTNNB might be regulated by unliganded TR. CCND1 and CTNNB may be involved in cell proliferation of metamorphosis. T3 might regulate the expression level of PI3K via nongenomic way. These results shed light on the mechanism of thyroid hormone in abalone metamorphosis. 相似文献
415.
LI Peng JIA Chengzao JIN Zhijun LIU Quanyou BI He ZHENG Min WU Songtao HUANG Zhenkai 《《地质学报》英文版》2020,94(2):219-232
Pore distribution and micro pore-throat structure characteristics are significant for tight oil reservoir evaluation, but their relationship remains unclear. This paper selects the tight sandstone reservoir of the Chang 7 member of the Xin’anbian Block in the Ordos Basin as the research object and analyzes the pore size distribution and micro pore-throat structure using field emission scanning electron microscopy(FE-SEM), high-pressure mercury injection(HPMI), highpressure mercury injection, and nuclear magnetic resonance(NMR) analyses. The study finds that:(1) Based on the pore size distribution, the tight sandstone reservoir is characterized by three main patterns with different peak amplitudes. The former peak corresponds to the nanopore scale, and the latter peak corresponds to the micropore scale. Then, the tight sandstone reservoir is categorized into three types: type 1 reservoir contains more nanopores with a nanopore-to-micropore volume ratio of 82:18;type 2 reservoir has a nanopore-to-micropore volume ratio of 47:53;and type 3 reservoir contains more micropores with a nanopore-to-micropore volume ratio of 35:65.(2) Affected by the pore size distribution, the throat radius distributions of different reservoir types are notably offset. The type 1 reservoir throat radius distribution curve is weakly unimodal, with a relatively dispersed distribution and peak ranging from 0.01 μm to 0.025 μm. The type 2 reservoir’s throat radius distribution curve is single-peaked with a wide distribution range and peak from 0.1 μm to 0.25 μm. The type 3 reservoir’s throat radius distribution curve is single-peaked with a relatively narrow distribution and peak from 0.1 μm to 0.25 μm. With increasing micropore volume, pore-throat structure characteristics gradually improve.(3) The correlation between micropore permeability and porosity exceeds that of nanopores, indicating that the development of micropores notably influences the seepage capacity. In the type 1 reservoir, only the mean radius and effective porosity have suitable correlations with the nanopore and micropore porosities. The pore-throat structure parameters of the type 2 and 3 reservoirs have reasonable correlations with the nanopore and micropore porosities, indicating that the development of these types of reservoirs is affected by the pore size distribution. This study is of great significance for evaluating lacustrine tight sandstone reservoirs in China. The research results can provide guidance for evaluating tight sandstone reservoirs in other regions based on pore size distribution. 相似文献
416.
Viruses of thermophiles are of great interest due to their roles in gene transfer, global geochemical cycle and evolution of life on earth. However, the thermophilic bacteriophages have not been studied extensively. In this investigation, a typical bacteriophage BV1 was obtained from a thermophilic bacterium Geobacillus sp. 6k512, which was isolated from an inshore hot spring in Xiamen of China. The BV1 contained a double-stranded linear DNA of 35 055 bp, which encodes 54 open reading frames (ORFs). Interestingly, eight of the 54 BV1 ORFs shared sequence similarities to genes from human disease-relevant bacteria. Seven proteins of the purified BV1 virions were identified by proteomic analysis. Determination of BV1 functional genomics would facilitate the better understanding of the mechanism for virus-thermophile interaction. 相似文献
417.
418.
高密度、集约化水产养殖业的发展导致疾病不断发生并呈现日趋严重之势,同时,由于细菌对传统抗生素产生耐药性而使抗生素的使用受到越来越多的限制,世界各国科学家都在致力于研究替代抗生素的新疗法。噬菌体因为可以特异性地杀死某些细菌,对动、植物以及环境都没有副作用,因此,在水产养殖病害防治中呈现良好的应用前景。本文从噬菌体的特异性、安全性、赋形方法以及对环境的影响等方面对国内外水产养殖中的噬菌体治疗研究现状和存在的主要问题进行了简要论述,为了解学科进展,促进噬菌体在治疗中的成功使用提供了理论依据。 相似文献
419.
分析了石鲈科4属10种鱼类S7核糖体蛋白基因内含子1部分序列特征,采用MP法和NJ法构建系统发育树.结果表明,在分子系统树上,10种石鲈科(Haemulidae)鱼类共组成两大类群,其中髭鲷属(Hapalogenys)鱼类和胡椒鲷属(Plectorhynchus)鱼类聚成一类群,石鲈属(Pomadasys)鱼类和仿石鲈属(Haemulon)鱼类聚成一类群,两类群再聚成一支,10种石鲈科鱼类构成单一分支类群.髭鲷属鱼类跟胡椒鲷属鱼类的亲缘关系较近.基于遗传距离分析表明,相对于石鲈属,髭鲷属鱼类跟仿石鲈属鱼类的遗传距离较小.因此,研究结果支持髭鲷属的分类地位是介于胡椒鲷属和仿石鲈属之间,未能从石鲈科中独立出来形成髭鲷科(Hapalogeniidae). 相似文献
420.