26 research outputs found
光通信用10Gbit/s Transponder的设计
本文分析了在高速光模块设计中介质损耗和微带结构对信号的影响,并对PCB中信号串扰模型的参数进行了计算.解决了高速光模块设计的一些关键问题,设计出满足MSA的300-pin transponder,并对模块进行了一系列性能和指标测试.测试结果表明,该模块完全满足SDH/SONET(STM-64/OC-192)以及10G Ethemet应用要求
四种水蛭抗凝血酶作用的研究
本文研究了水蛭的抗凝血酶作用,并比较了4种提取方法对抗凝作用的影响。冷浸和温浸,抗凝活性强度为菲牛蛭>日本医蛭》两种宽体金线蛭。煎煮后,前两种的活性锐碱,而两种宽体金线蛭的活性几乎不变
Effects of arbuscular mycorrhizal fungus on net ion fluxes in the roots of trifoliate orange(<i>Poncirus trifoliata</i>) and mineral nutrition in seedlings under zinc contamination
Situational evaluation method of the Chinese people’s holistic thinking characteristics and their application
创设了新的中国人思维特征的情境评估方法,初步应用于整体性思维特征与创造力倾向关系的研究并对其信效度进行了检验。新评估法选取体现典型文化意境和中国人思维特征的成语谜语作为材料,利用虚拟现实技术构建形与意、情境与语境相互转换的成语谜语文化园,记录被试游览时即景说出的成语建立成语库,并编码所录成语的思维特征类型以作为被试的整体性思维测量指标。基于测试数据的信效度分析表明整体性思维成语测试系统信效度表现良好。整体性思维与创造力倾向的相关分析表明,整体性思维与创造力倾向中的好奇性显著负相关。研究首次证实了利用虚拟现实技术来重建传统文化情境以实现对中国人思维特征的情境评估的可行性,提示基于虚拟现实技术的情境评估法在未来心理学相关研究中的应用价值。</p
Mechanomics analysis of hESCs under combined mechanical shear, stretch, and compression
Human embryonic stem cells (hESCs) can differentiate to three germ layers within biochemical and biomechanical niches. The complicated mechanical environments in vivo could have diverse effects on the fate decision and biological functions of hESCs. To globally screen mechanosensitive molecules, three typical types of mechanical stimuli,i.e.,tensile stretch, shear flow, and mechanical compression, were applied in respective parameter sets of loading pattern, amplitude, frequency, and/or duration, and then, iTRAQ proteomics test was used for identifying and quantifying differentially expressed proteins in hESCs. Bioinformatics analysis identified 37, 41, and 23 proteins under stretch pattern, frequency, and duration, 13, 18, and 41 proteins under shear pattern, amplitude, and duration, and 4, 0, and 183 proteins under compression amplitude, frequency, and duration, respectively, where distinct parameters yielded the differentially weighted preferences under each stimulus. Ten mechanosensitive proteins were commonly shared between two of three mechanical stimuli, together with numerous proteins identified under single stimulus. More importantly, functional GSEA and WGCNA analyses elaborated the variations of the screened proteins with loading parameters. Common functions in protein synthesis and modification were identified among three stimuli, and specific functions were observed in skin development under stretch alone. In conclusion, mechanomics analysis is indispensable to map actual mechanosensitive proteins under physiologically mimicking mechanical environment, and sheds light on understanding the core hub proteins in mechanobiology
Obtain the Transgenic Cucumber of the Fusion Gene of Region A of PAc Gene of Streptococcus mutans and B Subunit of
目的:经农杆菌介导将变异链球菌表面蛋白A区与霍乱毒素B亚单位嵌合基因导入黄瓜,获得转基因黄瓜植株,为转基因可食防龋疫苗的研究提供实验基础。方法:利用双元载体pCAMBIA2301构建变异链球菌表面蛋白A区与霍乱毒素B亚单位嵌合质粒(PAcA-ctxB)的植物表达载体p2355-PAcA-CTB;电转化法导入农杆菌EHA105;采用叶盘转化法转化黄瓜,转基因植物经过卡那霉素抗性筛选、GUS基因染色、PCR及Southern blot杂交分析检测目的基因鉴定。结果:成功得到转基因黄瓜植株,卡那霉素抗性筛选、GUS基因染色、PCR及Southern blot杂交分析检测证实目的基因PAcA-ctxB..
Effects of Trichoderma on nitrogen absorption and use efficiency in Lycium chinense roots under saline stress
To clarify the mechanisms underlying the improvement of Trichoderma on Chinese wolfberry (Lycium chinense) growth under saline stress,we analyzed the effects of application of organic fertilizer,Trichoderma agent and fertilizer on nitrogen uptake,assimilation,accumulation and use efficiency in Chinese wolfberry,based on a pot experiment with coastal saline soil.The organic fertilizer was the sterilization substance of Trichoderma fertilizer without viable Trichoderma,without any difference in the content of nutrients (such as nitrogen,phosphorus and potassium) between them.The results showed that the application of organic fertilizer,Trichoderma agent and fertilizer significantly increased NO_3~- and NH_4~+ influx rate in meristematic zone and NO_3~- influx rate in maturation zone of roots.The magnitude of such enhancement was greater in the application with Trichoderma fertilizer than organic fertilizer.Compared with the control,the application of Trichoderma agent and fertilizer significantly increased root,stem and leaf biomass and nitrogen content as well as plant nitrogen accumulation,strengthened root and leaf nitrate reductase,nitrite reductase and glutamine synthetase activities,and elevated nitrogen uptake efficiency,photosynthetic rate,stable carbon isotope abundance and photosynthetic nitrogen use efficiency.For all those variables,the beneficial effect was obviously stronger in the application with Trichoderma fertilizer than organic fertilizer.Therefore,Trichoderma facilitated nitrogen uptake,assimilation and accumulation in Chinese wolfberry under saline stress,improved photosynthetic carbon fixation ability and nitrogen use efficiency,and ultimately promoted plant growth
根际促生菌及木质素对持久性有机污染土壤修复的调控和酶活性的影响
近年来,持久性有机污染物对农田污染状况加剧,对人类食品安全和身体健康造成严重威胁。本实验以温室蔬菜基地中老化的有机污染土壤为目标,选取了DDTs和PAHs两种典型持久性有机污染物为去除对象,运用原位实验,研究了不同调控措施对有机污染土壤的修复效果及土壤酶活性的变化情况,并对污染物去除率与酶活性变化进行了相关性分析。结果表明,根际促生菌和木质素共同调控下的鼠李糖脂强化植物-微生物联合修复方法对有机污染物的去除效果最好,DDTs去除率为27.48%,PAHs去除率为53.26%;修复结束后,土壤多酚氧化酶、过氧化氢酶均被激活,激活程度表现为过氧化氢酶>多酚氧化酶,磷酸酶活性被抑制,使用Pearson双变量法对土壤酶活性与污染物去除率进行统计学分析发现,多酚氧化酶、磷酸酶与DDTs和PAHs去除率存在较好相关性,因此可以将这两种酶活性定义为修复过程中的一项微生态指标
