42 research outputs found
Molecular analysis of Trypanosoma cruzi isolates obtained from raccoons in Warren and Barren counties of Kentucky
Molecular Analysis of \u3ci\u3eTrypanosoma cruzi\u3c/i\u3e Isolates Obtained from Raccoons (\u3ci\u3eProcyon lotor\u3c/i\u3e) in Warren and Barren Counties of Kentucky
Trypanosoma cruzi, the etiologic agent of Chagas disease, infects a variety of wild mammals in the southern United States, but it has only recently been isolated from raccoons trapped in the state of Kentucky. The purpose of the present study was to use a molecular genotyping approach, followed by DNA sequencing to determine the genotypes (type I, or types IIa-IIe) of 15 of the Kentucky isolates. DNA samples were prepared from 15 T. cruzi- isolates using a Qiagen mini kit, and PCR amplification was performed using published primers for the 24S α rDNA sequence (D71 and D72), the non-transcribed spacer of the mini-exon genes (TC, TC1, and TC2), the 18S rDNA sequence (V1 and V2), and TCZ1 and TCZ2 primers that amplify a 188-base pair segment of the repetitive 195-bp nuclear DNA sequence of T. cruzi. DNA sequencing (ABI 3130 Genetic Analyzer) was performed on all amplification products obtained from the PCR analysis of the RW2 and RB12 isolates (randomly selected to represent both Warren and Barren counties of Kentucky; the number started with an “R” which stood for raccoon, a “W” for Warren County or a “B” for Barren County, followed by a number which represented the order in which animal was trapped). The resulting sequences were edited before analysis using the BLAST database of the National Center for Biotechnology Information (NCBI) Genbank. All 15 isolates were positively confirmed as T. cruzi based upon PCR amplification of a 195 bp repetitive genomic DNA sequence, and all 15 isolates showed identical PCR amplification results with all 4 sets of T. cruzi-specific primers. Two positive PCR samples were randomly selected for further DNA sequence analysis, and all samples were positively identified as the type IIa genotype of T. cruzi with max identities ranging from 94%-99%. The results of this study confirm that all hemoculture isolates obtained from raccoons trapped in Warren and Barren counties of Kentucky are T. cruzi. Furthermore, all BLAST comparisons of amplicon DNA sequences showed high sequence identity to type IIa strains of T. cruzi. The type IIa strain of T. cruzi is the most commonly reported genotype from raccoons trapped in the U.S.A
Engine knock detection and intensity evaluation based on sparse maximum correlation kurtosis devonvolution
Make Safe Decisions in Power System: Safe Reinforcement Learning Based Pre-decision Making for Voltage Stability Emergency Control
The high penetration of renewable energy and power electronic equipment bring
significant challenges to the efficient construction of adaptive emergency
control strategies against various presumed contingencies in today's power
systems. Traditional model-based emergency control methods have difficulty in
adapt well to various complicated operating conditions in practice. Fr emerging
artificial intelligence-based approaches, i.e., reinforcement learning-enabled
solutions, they are yet to provide solid safety assurances under strict
constraints in practical power systems. To address these research gaps, this
paper develops a safe reinforcement learning (SRL)-based pre-decision making
framework against short-term voltage collapse. Our proposed framework employs
neural networks for pre-decision formulation, security margin estimation, and
corrective action implementation, without reliance on precise system
parameters. Leveraging the gradient projection, we propose a security
projecting correction algorithm that offers theoretical security assurances to
amend risky actions. The applicability of the algorithm is further enhanced
through the incorporation of active learning, which expedites the training
process and improves security estimation accuracy. Extensive numerical tests on
the New England 39-bus system and the realistic Guangdong Provincal Power Grid
demonstrate the effectiveness of the proposed framework.Comment: 11 page
Calibration method of three-dimensional plane array laser radar based on space-time transformation
As a measurement system that can realize target detection and optical imaging, the accuracy of three-dimensional laser radar is a main performance index, which makes calibration an extremely important work. Traditional calibration methods have many disadvantages, such as harsh environment requirements, complex and tedious calibration processes, and inaccurate calibration results. To solve these problems, we propose a calibration method so that the relative position of the cooperative target and the detection sensor is fixed. The principle of space-time transform is used to simulate distance, and the synchronous control of distance is realized by controlling the delay module. In addition, a simple and practical calibration device is designed. In the actual measurement, the average absolute error is 0.0019 m, and the relative error is 0.0678% in the range of 0.5–25 m. The experimental results show that this method is stable and accurate, and it can calibrate the plane array laser radar quickly and accurately.</jats:p
Noise Source Identification of a Gasoline Engine Based on Parameters Optimized Variational Mode Decomposition and Robust Independent Component Analysis
Optical Butting of Plane Array Sensors for PA-LiDAR
In order to expand the field of view and improve the resolution, a method of optical butting was proposed for two plane array sensors using beam splitter prism in this paper. The principle of optical butting, the optical design, calibration and focusing technology, and alignment method were presented and analyzed. In addition, the gray image stitch and point cloud data registration were also realized. To prove the concept of the optical butting method, we built a prototype system for experiment. The splicing of two sensors of plane array laser imaging detection and ranging (PA-LiDAR) was implemented. After optical butting, the total effective pixel number was , the total effective area was mm, and the field of view was . Compared with the conventional laser radar system, the optical butting system can improve the field of view and resolution by a factor about . This method had the advantages of simple constitution, easy accomplishment, small space and high assembly precision which guaranteed the operating requirement of the PA-LIDAR sensor
