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991.
按当前网络发展的动向,引用专业垂直门户网站的概念,针对目前暖通网站的一些问题,从主页制作的步骤、常见问题、界面设计、艺术处理等方面,分别探讨了暖通网站建设要注意的问题,并提出了一些看法。 相似文献
992.
The present paper deals nine species of the genus Reticulitermes from HONG KONG, inwhich six species are new record. The key to species is given.All specimens are preserved separately in Nanjing Institute of Termite Control, Shanghai Institute of Entomology, Academia Sinica and Tai Lung Experimental Station, Agriculture and Fisheries Department, Hong Kong. 相似文献
993.
选准切入点,让北京城市绿化更加多姿多彩--北京城市园林绿化树种选择发展的思考 总被引:14,自引:0,他引:14
全面分析了北京城市绿化树种应用的现状和存在问题,对北京未来园林绿化树种的发展趋势提出了建议和对策,认为发展乡土树种,加强选种,育种工作,积极开展彩叶植物引种驯化,突出北京城市园林特色,是当前北京城市园林绿化树种选择和发展所面临的重要课题。 相似文献
994.
P. N. Buhl 《The International journal of environmental studies》2020,77(3):510-522
ABSTRACT The following five species are described as new to science: Inostemma muelleri sp. n., Metaclisis iranica sp. n., Platygaster curvistriata sp. n., Platygaster nepalica sp. n. and Prosynopeas antoni sp. n. The type material of Metaclisis ocalea (Walker) is described, and M. ocalea (Walker) and M. montagnei Maneval are synonymised with M. areolata (Haliday). 相似文献
995.
历史文化名城物种多样性初探 总被引:4,自引:0,他引:4
本文从生态学角度研究历史文化名城的文化环境。建立了城市文化生态系统的文化基因、文化物种、文化生态学的概念 ,确定了历史文化名城中有价值的文化物种 ,分析了物种在系统中的数量和变化状况。明确了城市保护应该重视城市中的各类文化物种 ,特别是稀有物种和处于衰败期的物种 ,维护城市中文化物种的多样性 ,实现城市文化生态系统的平衡与繁荣。 相似文献
996.
《Food Control》2015
Product mislabeling, adulteration, and substitution are increasing concerns in highly processed foods, including pet foods. Although regulations exist for pet foods, there is currently a lack of information on the prevalence of pet food mislabeling. The objective of this study was to perform a market survey of pet foods and pet treats marketed for domestic canines and felines to identify meat species present as well as any instances of mislabeling. Fifty-two commercial products were collected from online and retail sources. DNA was extracted from each product in duplicate and tested for the presence of eight meat species (bovine, caprine, ovine, chicken, goose, turkey, porcine, and equine) using real-time polymerase chain reaction (PCR) with SYBR Green and species-specific primers. Of the 52 tested products, 31 were labeled correctly, 20 were potentially mislabeled, and 1 contained a non-specific meat ingredient that could not be verified. Chicken was the most common meat species found in the pet food products (n = 51), and none of the products tested positive for horsemeat. In three cases of potential mislabeling, one or two meat species were substituted for other meat species, but major trends were not observed. While these results suggest the occurrence of pet food mislabeling, further studies are needed to determine the extent of mislabeling and identify points in the production chain where mislabeling occurs. 相似文献
997.
UV-Induced Cell Death in Plants 总被引:1,自引:0,他引:1
Ganesh M. Nawkar Punyakishore Maibam Jung Hoon Park Vaidurya Pratap Sahi Sang Yeol Lee Chang Ho Kang 《International journal of molecular sciences》2013,14(1):1608-1628
Plants are photosynthetic organisms that depend on sunlight for energy. Plants respond to light through different photoreceptors and show photomorphogenic development. Apart from Photosynthetically Active Radiation (PAR; 400–700 nm), plants are exposed to UV light, which is comprised of UV-C (below 280 nm), UV-B (280–320 nm) and UV-A (320–390 nm). The atmospheric ozone layer protects UV-C radiation from reaching earth while the UVR8 protein acts as a receptor for UV-B radiation. Low levels of UV-B exposure initiate signaling through UVR8 and induce secondary metabolite genes involved in protection against UV while higher dosages are very detrimental to plants. It has also been reported that genes involved in MAPK cascade help the plant in providing tolerance against UV radiation. The important targets of UV radiation in plant cells are DNA, lipids and proteins and also vital processes such as photosynthesis. Recent studies showed that, in response to UV radiation, mitochondria and chloroplasts produce a reactive oxygen species (ROS). Arabidopsis metacaspase-8 (AtMC8) is induced in response to oxidative stress caused by ROS, which acts downstream of the radical induced cell death (AtRCD1) gene making plants vulnerable to cell death. The studies on salicylic and jasmonic acid signaling mutants revealed that SA and JA regulate the ROS level and antagonize ROS mediated cell death. Recently, molecular studies have revealed genes involved in response to UV exposure, with respect to programmed cell death (PCD). 相似文献
998.
Hüseyin
zdikmen Didem Coral ahin Neslihan Bal 《Microscopy research and technique》2020,83(10):1171-1177
A new species, Cassida alidagiense sp. nov., has been described from Kayseri province in Turkey. For the time being, the species is endemic to Turkey. Cassida alidagiense sp. nov., is related to Cassida linnavuorii Borowiec, 1986; Cassida brevis Weise, 1884; and Cassida bella Faldermann, 1837, from which it differs in the shape of the apex of cornu of the spermethaca, and it can be distinctively differentiated from these species based on color of under body and spermathecal characters especially. In addition, the paper presents ultrastructures observed by SEM of spermatheca of Cassida alidagiense sp. nov. from Turkey. 相似文献
999.
Portunid crabs of the genus Portunus: P. pelagicus, P. gladiator and P. sanguinolentus and the genus Charybdis: C. natator and C. feriatus are economically important species for many tropical countries. An ongoing problem in the crab industry is involved with food labelling or food fraud in which many food manufacturers may have substituted the cheaper crabmeat for the more expensive ones due to the difficulty of species identification after many steps of food processing. To solve this problem, a convenient and accurate multiplex PCR assay using a species-specific primer set KUGEN_PORTspec was developed based on the nucleotide variation of cytochrome b and 28S ribosomal RNA. The primer set specifically amplified fragments of 286, 348, 418, 124 and 481 bp in P. pelagicus, P. gladiator, P. sanguinolentus, C. natator and C. feriatus, respectively, as well as a 220 bp positive control fragment. Specificity and sensitivity tests showed consistency in product sizes and absence of cross-species amplification with 0.1 ng DNA template limit of detection. Validation of the multiplex PCR assay on crabmeat prepared by steaming, mixing, freezing and canning was done and visualized by either agarose gel electrophoresis or automated capillary electrophoresis. The results indicated that the multiplex PCR assay using KUGEN_PORTspec is an effective tool for portunid species identification from both high- and low-quality DNA obtained from processed food. This newly developed primer set is an effective tool for crabmeat species identification to be used in future food industry and consumer protection programs. 相似文献
1000.
为了提高沙漠区低信噪比地震资料的品质,从优化野外资料采集的激发方式出发,开展了小药量单井多次激发组合叠加方法试验。根据地质任务要求、工区表层结构条件和激发信号的优势频带宽度,通过多种激发因素的野外试验综合确定小药量单井激发的合理药量;针对克服小药量单炮能量不足,同时又利于压制干扰波的要求,对野外主炮点上小药量单井组合参数与井位布设进行合理的设计,并在后续的室内组合叠加处理时优选最佳炮数的小药量资料;通过小药量单井资料的组合叠加处理与分析,获得不同地表条件下一个主炮点上小药量单井多次激发应布设的最佳井数(激发次数)。方法试验和试生产的应用效果表明,小药量单井多次激发组合叠加技术较好地提高了沙漠区地震资料信噪比和分辨率。 相似文献