Aim: One of the main diagnostic problems of conventional polymerase chain reaction (PCR) is indiscrimination of low parasitic loads in soil samples. The aim of this study is to determine the genetic diversity and identification of Toxocara spp. from public areas soil inferred by loop-mediated isothermal amplification (LAMP) assay. MATERIALS AND METHODS A total of 180 soil samples were collected from various streets and public parks of northwest Iran. The DNA of recovered Toxocara eggs were extracted and amplified by PCR and LAMP following ZnSO4 flotation technique. The amplicons of internal transcribed spacer-2 gene were sequenced to reveal the heterogeneity traits of Toxocara spp. In addition, Toxocara canis sequences of southwest Iran were directly retrieved to compare gene flow between two distinct populations. RESULTS Toxocara spp. eggs were found in 57, 14 and 77 of soil samples using the microscopy, PCR and LAMP (detection limit 1-3 eggs/200 g soil), respectively. 7.7% of isolates were identified as T. canis by PCR method, while LAMP was able to detect 27.2%, 15.5% and 12.2% as Toxocara cati, T. canis and mixed infections, respectively. The kappa coefficient between LAMP and microscopy indicated a strong agreement (0.765) but indicated a faint agreement among LAMP-PCR (0.203) and PCR-microscopy (0.308) methods. A pairwise fixation index (Fst) as a degree of gene flow was generally low (0.02156) among Toxocara populations of northwest and southwest Iran. CONCLUSIONS The statistically significant Fst value indicates that the T. canis populations are not genetically well differentiated between northwest and southwest Iran. This shows that here is possibly an epidemiological drift due to the transfer of alleles. The LAMP assay because of its shorter reaction time, more sensitivity, and simultaneous detection of environmental contamination to be appears as valuable field diagnosis compared to PCR. Therefore, the detection of low Toxocara spp. loads from public area soils will help to expand epidemiological understanding of toxocariasis and establishing preventive strategies in resource-limited endemic of Iran.

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Genetic variability and discrimination of low doses of Toxocara spp. from public areas soil inferred by loop-mediated isothermal amplification assay as a field-friendly molecular tool.

This paper presents the review of design variables optimization and control strategies of a Linear Switched Reluctance Actuator (LSRA).  The introduction of various type of linear electromagnetic actuators (LEA) are compared and the advantages of LSRA over other LEA are discussed together with the type of actuator configurations and topologies. The SRA provides an overall efficiency similar to induction actuator of the similar rating, subsequently the friction and windage losses are comparable but force density is better. LSRA has the advantage of low cost, simple construction and high reliability compare to the actuator with permanent magnet. However, LSRA also has some obvious defects which will influence the performance of the actuator such as ripples and acoustic noise which are caused by the highly nonlinear characteristics of the actuator. By researching the design variables of the actuator, the influences of those design variables are introduced and the detail comparisons are analyzed in this paper.  In addition, this paper also reviews on the control strategies in order to overcome the weaknesses of LSRA.

A Review: Design Variables Optimization and Control Strategies of a Linear Switched Reluctance Actuator for High Precision Applications

Linear switched reluctance motor (LSRM) and its applications in different industries have been an interesting research topic for the past few years. LSRMs have proved to be a suitable alternative in a variety of applications requiring linear motion. However, its use is not that popular which instigated an active interest in the evolution of newer LSRM configurations. Enhancement in its propulsion force along with the reduction in force ripples, weight, acoustic noise, and vibration have been the main objectives in recently proposed LSRM designs. In this paper, recently proposed LSRM designs are reviewed and analyzed. The paper presents a one-stop introduction and a complete update to the designs, both in terms of qualitative and quantitative parameters. In addition, it takes into account the challenges in the implementation of these designs. Based on a detailed comparison of these designs as presented in this paper, an appropriate design can be chosen for a given application. 

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Review of Linear Switched Reluctance Motor Designs for Linear Propulsion Applications

A novel tubular linear switched reluctance actuator (TLSRA) without permanent magnet that has 7:7 stator-to-mover pole pairs ratio is presented in this paper. A detailed analysis of the effect of mover parameters on the performances of proposed TLSRA is presented to determine the optimized actuator parameters. As comparison, the performances of the conventional TLSRA with 7:5 stator-to-mover pole pairs ratio is also designed and compared with the proposed TLSRA using the identical dimensions. The differences between the proposed and conventional TLSRA is number of available working pole pairs. The proposed TLSRA has four working pole pairs for a three phases actuator instead of two working pole pairs for conventional TLSRA. The additional working pole pairs in the proposed TLSRA exhibit force improvement, approximate two times higher compared to the conventional TLSRA. The static force characteristics for the proposed TLSRA is calculated and computed by using the three-dimensional finite element method (FEM) with ANSYS Maxwell software.

Design of a High Force Density Tubular Linear Switched Reluctance Actuator (TLSRA) Without Permanent Magnet

High starting force with reduced volume and mass are the primary importance in most of the linear transportation applications. This paper presents a novel tilted Linear Switched Reluctance Motor (LSRM) with reduced mass, volume, force ripple and improved force profile. Three Dimensional (3-D) finite element analyses are carried out on the proposed design to estimate the performance the motor. A thorough comparison has been made between the basic and the proposed structures. Experimental results reveal that, the proposed design is well suited for high starting force applications.

A Novel Skewed Linear Switched Reluctance Motor – Analysis and Design

Linear switched reluctance motors (LSRMs) are considered for numerous applications because of its inherent properties. The force ripple and hence acoustic noise and vibration make this machine failure in compete with the existing linear induction and linear synchronous machines. In this paper a new type of stator structure is proposed and experimented. The proposed structure provides less force ripple and vibration. Parameters like force ripple and vibration are predicted using finite element analysis (FEA). Experimental results are closely correlated with the predicted results.

R. Arumugam

Papers

A Novel Skewed Linear Switched Reluctance Motor – Analysis and Design

Design and Experimental Verification of Linear Switched Reluctance Motor with Tapered Poles