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991.
As an attractive alternative to plasmid DNA, messenger RNA (mRNA) has recently emerged as a promising class of nucleic acid therapeutics for biomedical applications. Advances in addressing the inherent shortcomings of mRNA and in the development of nanoparticle-based delivery systems have prompted the development and clinical translation of mRNA-based medicines. In this review, we discuss the chemical modification strategies of mRNA to improve its stability, minimize immune responses, and enhance translational efficacy. We also highlight recent progress in nanoparticle-based mRNA delivery. Considerable attention is given to the increasingly widespread applications of mRNA nanomedicine in the biomedical fields of vaccination, protein-replacement therapy, gene editing, and cellular reprogramming and engineering.  相似文献   
992.
A thermal emitter composed of a frequency-selective surface metamaterial layer and a hexagonal boron nitride-encapsulated graphene filament is demonstrated. The broadband thermal emission of the metamaterial (consisting of ring resonators) was tailored into two discrete bands, and the measured reflection and emission spectra agreed well with the simulation results. The high modulation frequencies that can be obtained in these devices, coupled with their operation in air, confirm their feasibility for use in applications such as gas sensing.
  相似文献   
993.
Wang  Yicun  Shi  Hongxi  Dong  Shuai  Li  Yan  Wang  Meng  Huai  Yanyan  Zhang  Xintong  Chen  Xi  Mao  Chuanbin  Gao  Xiang  Wang  Li 《Nano Research》2018,11(4):2248-2255
Nano Research - Candida albicans (C. albicans) infection has a high mortality rate in immunocompromised patients. Owing to the inefficiency of the current diagnostic system and the absence of...  相似文献   
994.
Multi-walled carbon nanotubes (MWCNTs) can act not only as a support for Fe3O4 nanoparticles (NPs) but also as a coworker with synergistic effect, accordingly improving the heterogeneous Fenton-like efficiency of Fe3O4 NPs. In this study, Fe3O4 NPs were in situ anchored onto MWCNTs by a moderate co-precipitation method and the as-prepared Fe3O4/MWCNTs nanocomposites were employed as the highly efficient Fenton-like catalysts. The analyses of XRD, FTIR, Raman, FESEM, TEM and HRTEM results indicated the formation of Fe3O4 crystals in Fe3O4/MWCNTs nanocomposites prepared at different conditions and the interaction between Fe3O4 NPs and MWCNTs. Over a wide pH range, the surface of modified MWCNTs possessed negative charges. Based on these results, the possible combination mechanism between Fe3O4 NPs and MWCNTs was discussed and proposed. Moreover, the effects of preparation and catalytic conditions on the Fenton-like catalytic efficiency were investigated in order to gain further insight into the heterogeneous Fenton-like reaction catalyzed by Fe3O4/MWCNTs nanocomposites.  相似文献   
995.
Shen  Lang  Poudel  Nirakar  Gibson  George N.  Hou  Bingya  Chen  Jihan  Shi  Haotian  Guignon  Ernest  Page  William D.  Pilar  Arturo  Cronin  Stephen B. 《Nano Research》2018,11(4):2310-2314
Nano Research - We report plasmon resonant excitation of hot electrons in a photodetector based on a metal/oxide/metal (Au/Al2O3/graphene) heterostructure. In this device, hot electrons, excited...  相似文献   
996.
在分析反舰导弹比例导引控制规律的基础上,将无线传感器网络信息融合思想引入到比例导引优化辅助决策控制过程中,通过将无线传感器网络信息融合中的数据、特征、决策概念对应于比例导引的具体数学模型,构建了基于无线传感器网络的比例导引优化信息融合辅助决策架构;利用VB6.0语言对基于无线传感器网络辅助决策的反舰导弹优化信息融合制导控制规则进行了模拟仿真,命中距离缩短约37.1%,命中时间节省约10.9%;仿真实验结果实现了反舰导弹自适应优化比例系数的比例制导律,验证了该方法的有效性。  相似文献   
997.
Origami-based metamaterials have widespread application prospects in various industries including aerospace, automotive, flexible electronics, and civil engineering structures. Among the wide range of origami patterns, the fourfold tessellation known as Miura-ori is of particular attraction to engineers and designers. More specifically, researchers have proposed different 3D structures and metamaterials based on the geometric characteristics of this classic origami pattern. Herein, a computational modeling approach for the design and evaluation of 3D cellular solids with the Miura-ori metamaterial geometry which can be of zero or nonzero thicknesses is presented. To this end, first, a range of design alternatives generated based on a numerical parametric model is designed. Next, their mechanical properties and failure behavior under quasistatic axial compressive loads along three perpendicular directions are analyzed. Then, the effects of various geometric parameters on their energy absorption behavior under compression in the most appropriate direction are investigated. The findings of this study provide a basis for future experimental investigations and the potential application of such cellular solids for energy-absorbing purposes.  相似文献   
998.
Flush toilets waste a significant amount of water every day due to the unavoidable adhesions between human waste and the toilet surfaces. Super-slippery surfaces can repel complex fluids and various viscoelastic solids, however, are easily broken by mechanical abrasions. Herein, the fabrication of an abrasion-resistant super-slippery flush toilet (ARSFT) is reported using a selective laser sintering 3D printing technology. Unlike traditional super-slippery surfaces with limited thicknesses which can be easily worn away, the powder-sintered strategy endows the ARSFT not only with a self-supporting 3D complex shape but also with a porous structure that can accommodate considerable lubricants for an abrasion-resistant super-slippery property. As a result, the as-prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids. Besides liquids, the ARSFT exhibits a high resistance to sticky synthetic feces. Notably, even after being abraded to 1,000 cycles of abrasion using sandpaper, the ARSFT maintains its record-breaking super-slippery capability. The concept of the 3D-printed object with a superior abrasion-resistant slippery ability will improve the development of super-slippery materials and further save water consumption in the human society.  相似文献   
999.
Along with the booming development of communication technology and electronic equipment, higher requirements of flame-retardant and EMI shielding performances for electromagnetic interference (EMI) shielding materials are put forward. Herein, the ultralight and porous silver nanowires (AgNWs)-melamine formaldehyde (MF) hybrid composite with unique micro-/nanostructure is developed by a facile dip-coating method, which uses the AgNWs as 1D conductive coating and MF foam (MF foam) as 3D skeleton template. Benefiting from the unique porous micro-/nanostructure, the resultant hybrid composite displays low density, excellent EMI shielding performances, and superior flame-retardant property. The EMI shielding effectiveness (SE) and specific EMI SE (SSEt) of the hybrid composite in X-band (8.2–12.4 GHz) can be up to 77 dB and 26971.4 dB cm−2 g−1, respectively. At the same time, the hybrid composite also passes the vertical burning test and shows an increased LOI value of 40.6%. The combination of flame-retardant and EMI shielding performances for EMI shielding materials makes the AgNWs-MF hybrid composite great application potential in civil and military fields. This work provides a new guide for the design of multifunctional high-performance EMI shielding materials.  相似文献   
1000.
In the era of big data, traditional regression models cannot deal with uncertain big data efficiently and accurately. In order to make up for this deficiency, this paper proposes a quantum fuzzy regression model, which uses fuzzy theory to describe the uncertainty in big data sets and uses quantum computing to exponentially improve the efficiency of data set preprocessing and parameter estimation. In this paper, data envelopment analysis (DEA) is used to calculate the degree of importance of each data point. Meanwhile, Harrow, Hassidim and Lloyd (HHL) algorithm and quantum swap circuits are used to improve the efficiency of high-dimensional data matrix calculation. The application of the quantum fuzzy regression model to small-scale financial data proves that its accuracy is greatly improved compared with the quantum regression model. Moreover, due to the introduction of quantum computing, the speed of dealing with high-dimensional data matrix has an exponential improvement compared with the fuzzy regression model. The quantum fuzzy regression model proposed in this paper combines the advantages of fuzzy theory and quantum computing which can efficiently calculate high-dimensional data matrix and complete parameter estimation using quantum computing while retaining the uncertainty in big data. Thus, it is a new model for efficient and accurate big data processing in uncertain environments.  相似文献   
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