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111.
Plant laccase genes belong to a multigene family, play key roles in lignin polymerization, and participate in the resistance of plants to biotic and abiotic stresses. Switchgrass is an important resource for forage and bioenergy production, yet information about the switchgrass laccase gene family is scarce. Using bioinformatic approaches, a genome-wide analysis of the laccase multigene family in switchgrass was carried out in this study. In total, 49 laccase genes (PvLac1 to PvLac49) were identified; these can be divided into five subclades, and 20 of them were identified as targets of miR397. The tandem and segmental duplication of laccase genes on Chr05 and Chr08 contributed to the expansion of the laccase family. The laccase proteins shared conserved signature sequences but displayed relatively low sequence similarity, indicating the potential functional diversity of switchgrass laccases. Switchgrass laccases exhibited distinct tissue/organ expression patterns, revealing that some laccases might be involved in the lignification process during stem development. All five of the laccase isoforms selected from different subclades responded to heavy metal. The immediate response of lignin-related laccases, as well as the delayed response of low-abundance laccases, to heavy-metal treatment shed light on the multiple roles of laccase isoforms in response to heavy-metal stress.  相似文献   
112.
With the development of laser technologies,nuclear reactions can happen in high-temperature plasma environments induced by lasers and have attracted a lot of at...  相似文献   
113.
《精细化工工艺》课程教学改革的研究   总被引:1,自引:0,他引:1  
文章论述了合理组织教材以突出教材的重点,凸显知识体系的规律性;精讲教材内容,使学生抓住精细化工的实质;课堂教学与实验内容相结合以增强学生对精细化工理论和实验的理解;把科研内容引入教学中以激起学生的学习兴趣及对科学知识探求的热情;充分利用外部教学条件,把教学与精细化工生产实际结合起来,以培养学生的实际技能等方面的内容。  相似文献   
114.
同轴式双空心抽油杆加热系统可有效解决高凝油井井筒易结蜡、稠油井产液黏度较高的问题,但考虑油井生产效率、开采成本及综合的经济效益,需要计算出最佳的抽油杆下入深度。以井口出油温度最优为目标,同轴式双空心抽油杆下入深度、循环水进口温度为约束条件,建立了井口出油温度C计算模型。利用该模型进行求解时,先用迭代法进行同轴式双空心抽油杆下入深度优化,然后在优化结果基础上进行抽油机载荷校核。建立的井口出油温度计算模型及同轴式双空心抽油杆下入深度确定方法,在现场13口油井进行了应用。结果表明,该方法避免了以前设计人员凭经验确定抽油杆下深的弊端,可靠性更高,且有效时率平均提高14.1百分点,既满足了生产需要又节省了油井开发成本。   相似文献   
115.
116.
As one of the most important factors in alternative splicing (AS) events, serine/arginine-rich (SR) proteins not only participate in the growth and development of plants but also play pivotal roles in abiotic stresses. However, the research about SR proteins in cotton is still lacking. In this study, we performed an extensive comparative analysis of SR proteins and determined their phylogeny in the plant lineage. A total of 169 SR family members were identified from four Gossypium species, and these genes could be divided into eight distinct subfamilies. The domain, motif distribution and gene structure of cotton SR proteins are conserved within each subfamily. The expansion of SR genes is mainly contributed by WGD and allopolyploidization events in cotton. The selection pressure analysis showed that all the paralogous gene pairs were under purifying selection pressure. Many cis-elements responding to abiotic stress and phytohormones were identified in the upstream sequences of the GhSR genes. Expression profiling suggested that some GhSR genes may involve in the pathways of plant resistance to abiotic stresses. The WGCNA analysis showed that GhSCL-8 co-expressed with many abiotic responding related genes in a salt-responding network. The Y2H assays showed that GhSCL-8 could interact with GhSRs in other subfamilies. The subcellular location analysis showed that GhSCL-8 is expressed in the nucleus. The further VIGS assays showed that the silencing of GhSCL-8 could decrease salt tolerance in cotton. These results expand our knowledge of the evolution of the SR gene family in plants, and they will also contribute to the elucidation of the biological functions of SR genes in the future.  相似文献   
117.
介绍了某型导弹发控盒电路板综合测试系统的硬件和软件设计,该系统以PC计算机为平台,采用总线式设计思想,实现了对电路板检测的自动化、快速化和智能化.  相似文献   
118.
汽车已经成为现代物质文明的一种象征和人类生活中不可缺少的部分,而汽车在一个国家的普及程度,也成为衡量其工业化的重要标志.本文论述了国内外汽车产品发展状况和汽车产品的开发体系.  相似文献   
119.
Medication adherence—taking medication as prescribed—is critical for successful self-care, especially among older adults. Adherence depends on developing and implementing plans for taking medications. Age-related cognitive declines that affect adherence may be mitigated using external tools that support patient-provider collaboration needed to develop these adherence plans. We tested the effectiveness of structured collaborative medication tools to support better medication planning and adherence practices. Evidence for benefits of collaborative tools has been mixed in terms of their usefulness for medication-scheduling tasks, perhaps because the tools have not been explicitly designed to support patient-provider collaboration. A total of 144 community-dwelling older adults participated in pairs and performed the role of a patient or provider in a simulated patient-provider medication-scheduling task. Each pair worked with a structured (MedTable? and e-MedTable) or unstructured (Medcard) scheduling tool and completed four problems (2 simple and 2 complex). Performance was measured using the following: problem-solving (medication schedule) accuracy, problem-solving time, solution (schedule) optimality, tool usability, collaborative effectiveness, and subjective workload involved in creating the medication schedules. Participants using structured tools produced more accurate and optimal schedules. They also rated subjective workload as lower and thought that the structured tools were easier to use, reduced subjective workload associated with creating the schedules. There was also suggestive evidence that participants using the structured tools rated more highly the quality of their collaboration. Structured medication-scheduling tools have the potential to improve medication adherence among older adults because they support collaborative planning and reduce the cognitive load involved in creating these adherence plans.  相似文献   
120.
男同性恋群体的城市空间分布及文化生产:以沈阳为例   总被引:3,自引:0,他引:3  
富晓星  吴振 《工程研究》2010,2(1):38-52
From the pespective of space-culture, this paper explores how gay people's body, behavior and social relations are organized, represented and understood in Shenyang city by adopting participating observation, in-depth individual interview and historical literature review. Through the interaction between the urban space and the gay groups' inner characteristics, this paper finds out that the urban space constructs a dynamic platform for the mobilization of homosexual behavior, emotion and identity.  相似文献   
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