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91.
肿瘤细胞增殖与骨吸收之间的恶性循环加剧了骨肿瘤的进展和转移风险.为此,我们设计并制备了聚乙二醇-阿仑膦酸钠修饰的聚多巴胺(PPA)纳米粒子,并在其表面负载自噬抑制剂氯喹(CQ),期望利用该治疗载体(PPA/CQ)打破肿瘤细胞增殖与骨吸收之间的恶性循环,从而有效地治疗骨肿瘤.实验证明,PPA/CQ可以有效地富集到骨组织,...  相似文献   
92.
Sclerotinia head rot (HR), caused by Sclerotinia sclerotiorum, is an economically important disease of sunflower with known detrimental effects on yield and quality in humid climates worldwide. The objective of this study was to gain insight into the genetic architecture of HR resistance from a sunflower line HR21 harboring HR resistance introgressed from the wild perennial Helianthus maximiliani. An F2 population derived from the cross of HA 234 (susceptible-line)/HR21 (resistant-line) was evaluated for HR resistance at two locations during 2019–2020. Highly significant genetic variations (p < 0.001) were observed for HR disease incidence (DI) and disease severity (DS) in both individual and combined analyses. Broad sense heritability (H2) estimates across environments for DI and DS were 0.51 and 0.62, respectively. A high-density genetic map of 1420.287 cM was constructed with 6315 SNP/InDel markers developed using genotype-by-sequencing technology. A total of 16 genomic regions on eight sunflower chromosomes, 1, 2, 10, 12, 13, 14, 16 and 17 were associated with HR resistance, each explaining between 3.97 to 16.67% of the phenotypic variance for HR resistance. Eleven of these QTL had resistance alleles from the HR21 parent. Molecular markers flanking the QTL will facilitate marker-assisted selection breeding for HR resistance in sunflower.  相似文献   
93.
The spatiotemporal evolution of hairpin vortex structures in a fully developed turbulent boundary layer is investigated qualitatively and quantitatively by usin...  相似文献   
94.
High concentrations of defects are introduced into nanoscale ZnO through non‐equilibrium processes and resultant blue emissions are comprehensively analyzed, focusing on defect origins and broad controls. Some ZnO nanoparticles exhibit very strong blue emissions, the intensity of which first increase and then decrease with annealing. These visible emissions exhibit strong and interesting excitation dependences: 1) the optimal excitation energy for blue emissions is near the bandgap energy, but the effective excitation can obviously be lower, even 420 nm (2.95 eV < Eg = 3.26 eV); in contrast, green emissions can be excited only by energies larger than the bandgap energy; and, 2) there are several fixed emitting wavelengths at 415, 440, 455 and 488 nm in the blue wave band, which exhibit considerable stability in different excitation and annealing conditions. Mechanisms for blue emissions from ZnO are proposed with interstitial‐zinc‐related defect levels as initial states. EPR spectra reveal the predominance of interstitial zinc in as‐prepared samples, and the evolutions of coexisting interstitial zinc and oxygen vacancies with annealing. Furthermore, good controllability of visible emissions is achieved, including the co‐emission of blue and green emissions and peak adjustment from blue to yellow.  相似文献   
95.
水利工程模型试验计算机测量与控制系统   总被引:1,自引:0,他引:1  
采用计算机测量与控制系统应用于水利工程模型试验,设计应用先进的水流循环系统、电磁流量计、电子式电动调节阀、控制接口和软件组成计算机流量闭环自动控制系统;计算机测量与控制系统通过实际使用运行,证明达到了设计指标的要求,大大提高了模型试验测量与控制的精度和工作效率,缩短了模型试验周期,有利于水利工程研究成果质量和科研水平的提高.  相似文献   
96.
已有砖砌体房屋底层常因功能改变而需要更大的使用空间,部分承重墙体的抽除必将导致传力途径的改变,故需对原有结构进行加固。阐述了托换技术在房屋改造加固中的应用,同时对托换技术的各设计阶段,包括基础设计、结构设计等作了分析。  相似文献   
97.
To study the influence of an anisotropic parabolic potential(APP)on the properties of a quantum dot(QD)qubit,we obtain the eigenenergies and eigenfunctions of the ground and first excited state of an electron,which is strongly coupled to the bulk longitudinal optical(LO)phonons,in a QD under the influence of an APP by the celebrated Lee–Low–Pines(LLP)unitary transformation and the Pekar type variational(PTV)methods.Then,this kind of two-level quantum system can be excogitated to constitute a single qubit.When the electron locates at the superposition state of its related eigenfunctions,we get the time evolution of the electron’s probability density.Finally,the influence of an APP on the QD qubit is investigated.The numerical calculations indicate that the probability density will oscillate periodically and it is a decreasing function of the effective confinement lengths of theAPPindifferentdirections.Whereasitsoscillatoryperiodisanincreasingoneandwilldiminishwithenhancing the electron–phonon(EP)coupling strength.  相似文献   
98.
Perovskite solar cells (PSCs) emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from ...  相似文献   
99.
Ambient Media describe media environments, where the medium is embedded within the natural environment. They follow the anytime, anywhere, and anyhow principle for media access. The Nokia Ubimedia MindTreks Awards have been established a few years ago to explore the potential of ambient media. In this article we analyze the total project portfolio submitted to the 4th Nokia Ubimedia MindTrek Awards in 2010 according to their business value, innovativeness, and use of ambient media. The aim of this article is to gain insights into the general characteristics of ambient media, their properties, and business functions. The article rounds up in providing a substantial framework and guidelines for ambient media developers in their product designs.  相似文献   
100.
在统计分析了近10年来全国电网运行各类故障的基础上,对当前电网事故发生的特点和规律进行了分析总结,指出了制约电网安全运行的主要因素,并提出了相应的对策。  相似文献   
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