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1.
Spinal muscular atrophy (SMA) is an autosomal recessive hereditary neuromuscular disease. Exon 7 and 8 of survival of motor neuron 1 (SMN1) gene or only exon 7 homology deletion leads to the failure to produce a full-length SMN gene. The copy number of SMN2 gene with high homology of SMN1 affects the degree of disease and was the target gene for targeting therapy, in which splicing silencer in intron 7 was the key to suppress the inclusion of exon 7. In this study, we projected to use CRISPR/Case 9 for the targeted editing of intronic-splicing silencer (ISS) sequence to promote the inclusion of SMN2 exon 7 and increase the production of SMN2 full-length (FL) gene expression. It happens that there was a protospacer adjacent motif (PAM) at one end of the ISS sequence according to the design of sgRNA. The recombinant vector of sgRNA HSMN2 CRISPR/Case 9 was constructed and transfected into HEK293 cells. Sequencing results showed that the ISS sequence could be edited accurately and targeting in the predicted direction, in which deleting small fragments, inserting small amounts and mutation. Quantitative analysis of RT-PCR products by restriction enzyme of DdeI digestion showed that the FL of SMN2 increased by 8% (P < 0.05). In the primary cultured chondrocytes of SMA mice, in which sgRNA HSMN2 CRISPR/Case9 recombinant vector transfection could increase the SMN2 FL gene by 23% (P < 0.05) and significantly improve SMN protein levels (P < 0.05). CRISPR/Case 9 is an effective tool for gene editing and therapy of hereditary diseases, but it is rarely reported in the treatment of SMA diseases. This study shows that CRISPR/Case 9 was first used for the precision target of ISS sequence editing, which can effectively promote the production of SMN2 FL gene expressions, in which there was an important clinical reference value.  相似文献   
2.
In this paper, the problem of output consensus for multiple non-holonomic systems in chained form has been investigated. First, an output consensus controller under the strongly connected communication topology is devised by two steps, where a time-varying control strategy and the backstepping design technique are employed. Then, the results are extended to the general directed topology case via graph decomposition, in which the input-to-state stability theory plays a critical role. We prove that the proposed controller can achieve the semi-global output consensus among multiple non-holonomic systems, provided that the interaction graph contains a spanning tree. Finally, numerical examples are provided to illustrate the effectiveness of the designed controller.  相似文献   
3.
Automated visual inspection (AVI) attracts increasing interest in product quality control both academic and industrial communities, particularly on mass production processes, because product qualities of most types can be characterized with their corresponding surface visual attributes. However, many product images in AVI systems are comprised of stochastically accumulative fragmentations (particles) of local homogeneity, without distinctive foregrounds and backgrounds, which brings great challenges in computer analysis, e.g., rice images, fabric images, and consequently, in the intelligent identification of the product qualities. A method of Weibull distribution (WD)-based statistical modeling of image spatial structures (ISSs) to inspect automatically the product quality is presented. The ISS, obtained with multi-scale and omnidirectional Gaussian derivative filters (OGDFs), was demonstrated to be subject to a representative WD model of integral form based on the theory of sequential fragmentation in advance. The WD-model parameters (WD-MPs) of the ISS, with essential human perceptual significance, were extracted as the visual features for product quality identification. The classification performance of the proposed product quality inspection method, namely, the proposed WD-MP features integrated with an introduced spline regression (SR) classifier in this study, was verified on two case studies in the field of the AVI of product quality, namely, automated rice quality classification, and intelligent fabric quality assessment in the corresponding assembly lines of industrial scale. Experimental results indicate that the proposed WD-MP features can effectively characterize the statistical distribution profiles of ISS of complex grain images, piled with a large number of stochastically accumulative fragmentations. The proposed method provides an effective tool for grain image modeling and analysis and consequently lays a foundation for the intelligent perception of product qualities on assembly lines.  相似文献   
4.
赵朋朋  张军  刘毅 《中州煤炭》2016,(10):138-141
槽波勘探技术具有能量强、信噪比高、探测距离长、勘探精度高等特点,在隐蔽致灾因素探测方面发挥了重要作用。在单一巷道中解决工作面内部的构造问题只能依靠槽波反射法勘探,因为槽波反射勘探可以将激发点和接收点布置在同一条巷道,受空间限制程度较小,在实际应用中有一定的优势和实用价值。结合实例介绍了槽波反射勘探的基本原理,详细说明了此次槽波反射勘探的施工工艺、数据处理流程等。经过验证对比,地质效果良好。只要观测系统合理,槽波反射勘探在解决工作面内部小构造问题方面有一定优势。  相似文献   
5.
ISS高密度地震采集是以干扰炮相对有效炮为随机信号的基本理念对地震数据进行采集的方法,其大部分有效信号会淹没于噪声之中。基于此,本文提出-种在十字排列域或检波点域进行矢量中值滤波方法,并针对理论模型简要分析了不同空间滤波参数对保持有效信号和压制干扰信号的影响及处理中应注意的问题;实际单炮地震数据的处理和叠加成像结果表明,该方法在有效压制相干炮噪声的同时,能够较好地保持有效信号,提高资料信噪比,显著优于常规去噪方法的处理效果。  相似文献   
6.
The paper describes BIC 3, the latest prototype of inertial balance made at INRIM (former IMGC–CNR) in view of its possible use on board the International Space Station. The main characteristic of this instrument is its ability to work both in weightless conditions and on Earth surface with metrological performances comparable to those of a laboratory-level classic balance. BIC 3, although still based on the same centrifugal method adopted in the two previous prototypes, widely differs from them as regards configuration (constant speed), main motor characteristics (here a stepping motor is used), force transducer (the integral beam of a commercially-available balance), and consequently shows metrological performances considerably improved. The main constructional features are described and the metrological characteristics resulted from on-Earth tests are reported and discussed. A test made of 175 measurements in the range 0–150 g showed an expanded uncertainty of 4.1 mg.  相似文献   
7.
A detailed analysis of the As-exposed Si (112) and subsequent Te exposure was performed. X-ray photoelectron spectroscopy shows that the Te- and As-exposed Si (112) surface had 70% As and 27% Te coverage, respectively. Direct surface coverage measurement with ion scattering spectroscopy (ISS) shows that the Si (111) surface is completely covered by As, and that of the Si (112) had about 78% and 20% coverage of As and Te, respectively. Finally, using ISS shadowing effects, it was found that the Te atoms were positioned mainly on the step edges.  相似文献   
8.
分析了欧洲自动转移飞行器。首先介绍其研制概况、货运能力,然后分析其总体结构和飞行任务,探讨其发展潜力、总结其设计特色,最后展望其未来应用。  相似文献   
9.
The three main methods for oxidation of metallic substrates, thermal, anodic and plasma have been applied to a copper, titanium, and zirconium alloy and its corresponding binaries (Cu–33Ti–33Zr, Cu–50Ti, Cu–50Zr and Ti–50Zr). Polished polycrystalline samples of these alloys were examined before treatment, after vacuum thermal annealing at 100°C and heating in 20 mTorr oxygen at 100, 200, and 300°C. ISS depth profiles were taken of selected samples. The least-noble component oxidizes first, but at high temperatures and with plasma oxidation the noble component segregates to the surface. A comparison of the resulting structures on the ternary and binary alloys with different oxidation methods is used to explore the physico-chemical processes during oxidation. Results from these three methods are discussed in terms of physical/chemical parameters that influence the chemical nature and structure of the resulting oxides. The electrochemical processes that occur during the materials reaction with a chosen environment are used to discuss the physical and chemical mechanisms involved. Intrinsic (thermal and plasma oxidation) and extrinsic (electrochemical oxidation) electric fields are shown to influence the chemical and structural nature of the resulting oxide structures. The influence of transport phenomena is discussed.  相似文献   
10.
MPC or model predictive control is representative of control methods which are able to handle inequality constraints. Closed-loop stability can therefore be ensured only locally in the presence of constraints of this type. However, if the system is neutrally stable, and if the constraints are imposed only on the input, global asymptotic stability can be obtained; until recently, use of infinite horizons was thought to be inevitable in this case. A globally stabilizing finite-horizon MPC has lately been suggested for neutrally stable continuous-time systems using a non-quadratic terminal cost which consists of cubic as well as quadratic functions of the state. The idea originates from the so-called small gain control, where the global stability is proven using a non-quadratic Lyapunov function. The newly developed finite-horizon MPC employs the same form of Lyapunov function as the terminal cost, thereby leading to global asymptotic stability. A discrete-time version of this finite-horizon MPC is presented here. Furthermore, it is proved that the closed-loop system resulting from the proposed MPC is ISS (Input-to-State Stable), provided that the external disturbance is sufficiently small. The proposed MPC algorithm is also coded using an SQP (Sequential Quadratic Programming) algorithm, and simulation results are given to show the effectiveness of the method.  相似文献   
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