Characterization and control of a pneumatic microactuator with an integrated inductive position sensor

As the intelligence and the functionality of microrobots increase, there is a growing need to incorporate sensors into these robots. In order to limit the outer dimensions of these microsystems, this research investigates sensors that can be integrated efficiently into microactuators. Here, a pneumatic piston-cylinder microactuator with an integrated inductive position sensor was developed. The main advantage of pneumatic actuators is their high force and power density at microscale. The outside diameter of the actuator is 1.3 mm and the length is 15 mm. The stroke of the actuator is 12 mm, and the actuation force is 1 N at a supply pressure of 1.5 MPa. The position sensor consists of two coils wound around the cylinder of the actuator. The measurement principle is based on the change in coupling factor between the coils as the piston moves in the actuator. The sensor is extremely small since one layer of 25 μm copper wire is sufficient to achieve an accuracy of 10 μm over the total stroke. Position tests with a PI controller and a sliding mode controller showed that the actuator is able to position with an accuracy up to 30 μm. Such positioning systems offer great opportunities for all devices that need to control a large number of degrees of freedom in a restricted volume. © 2007 Elsevier B.V. All rights reserved.

Subcellular localization and inductive expression of the dsRNA-dependent protein kinase PKR from Japanese flounder, Paralichthys olivaceus

The double-stranded RNA (dsRNA)-dependent protein kinase (PKR) belongs to the eIF2 alpha kinase family and plays a critical role in interferon (IFN)-mediated antiviral response. Recently, in Japanese flounder (Paralichthys olivaceus), a PKR gene has been identified. In this study, we showed that PoPKR localized to the cytoplasm, and the dsRNA-binding motifs (dsRBMs) played a determinative role in protein localization. In cultured FEC cells, PoPKR was detected at a low level of constitutive expression but was highly induced after treatment with UV-inactivated grass carp hemorrhagic virus, active SMRV and Poly I:C although with different expression kinetics. In flounder, PoPKR was ubiquitously distributed in all tested tissues, and SMRV infection resulted in significant upregulation at mRNA and protein levels. In order to reveal the role of PoPKR in host antiviral response, its expression upon exposure to various inducers was characterized and further compared with that of PoHRI, which is another eIF2 alpha kinase of flounder. Interestingly, expression comparison revealed that all inducers stimulated upregulation of PoHRI in cultured flounder embryonic cells and fish, with a similar kinetics to PoPKR but to a less extent. These results suggest that, during antiviral immune response, both flounder eIF2 alpha kinases might play similar roles and that PoPKR is the predominant kinase. (C) 2009 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

Inductive transcription and protective role of fish heme oxygenase-1 under hypoxic stress

Heme oxygenase-1 is the rate-limiting enzyme in the degradation of heme into biliverdin, carbon monoxide and free divalent iron. In this study, we cloned heme oxygenase isoform 1 (CaHO-1) from a hypoxia-tolerant teleost fish Carassius auratus. The full-length cDNA of CaHO-1 is 1247 bp and encodes a protein of 272 amino acids. RT-PCR and real-time PCR analysis indicated that CaHO-1 was predominantly transcribed in posterior kidney, head kidney, gill and intestine, and induction of gene transcription was observed predominantly in posterior kidney under hypoxic stress. Moreover, the hypoxia-induced transcription was confirmed in goldfish larvae and in in vitro cultured CAB cells. Fluorescence of the HO-1-GFP fusion protein revealed a cytoplasmic and plasma membrane localization, which was consistent with the putative transmembrane structure. Subsequently, we established a stably transfected CAB/pcDNA3.1-HO-1 cell line and a control CAB/pcDNA3.1 cell line, and found that the number of dead cells was obviously reduced in the pcDNA3.1-HO-1-transfected group following 4 days of hypoxic (1% O-2) treatment in comparison with numerous detached dead cells in the control pcDNA3.1-transfected cells. Furthermore, a significant cell viability difference between the two kinds of transfected cells during hypoxia-reoxygenation was revealed. Therefore, the data suggest that fish HO-1 might play a significant protective role in cells in response to hypoxic stress.

Molecular characterisation and inductive expression of a fish protein arginine methyltransferase 1 gene in response to virus infection

Protein arginine methyltransferase 1 (PRMT1) is currently thought as an effector to regulate interferon (IFN) signalling. Here Paralichthys olivaceus PRMT1 (PoPRMT1) gene was identified as a vitally induced gene from UV-inactivated Scophthalmus maximus Rhabdovirus (SMRV)-infected flounder embryonic cells (FEC). PoPMRT1 encodes a 341-amino-acid protein that shares the conserved domains including post-I, motif I, II and III. Homology comparisons show that the putative PoPMRT1 protein is the closest to zebrafish PMRT1 and belongs to type I PRMT family (including PRMT1, PRMT2, PRMT3, PRMT4, PRMT6, PRMT8). Expression analyses revealed an extensive distribution of PoPMRT1 in all tested tissues of flounder. In vitro induction of PoPRMT1 was determined in UV-inactivated SMRV-infected FEC cells, and under the same conditions, flounder Mx wash also transcriptionally up-regulated, indicating that an IFN response might be triggered. Additionally, live SMRV infection of flounders induced an increased expression of PoPRMT1 mRNA and protein significantly in spleen, and to a lesser extent in head kidney and intestine. Immunofluorescence analysis revealed a major cyptoplasmic distribution of PoPRMT1 in normal FEC but an obvious increase occurred in nucleus in response to UV-inactivated SMRV. This is the first report on in vitro and in vivo expression of fish PRMT1 by virus infection, suggesting that PoPRMT1 might be implicated in flounder antiviral immune response. (c) 2006 Elsevier Ltd. All rights reserved.

Inductive expression and characterization analysis of Paralichthys olivaceus pigment epithelium-derived factor in a virally infected cell line

Pigment epithelium-derived factor (PEDF) is acknowledged to be a non-inhibitory member of the serine protease inhibitor (serpin) superfamily, with antiangiogenesis, and neuroprotective and immumoregulatory function, mainly in the tissues of nervous system. Here, A PEDF gene homolog, Paralichthys olivaceus PEDF (PoPEDF), was isolated from flounder embryonic cells (FEC) treated with UV-inactivated Grass carp hemorrhage virus (GCHV) and subsequently identified as a differentially expressed gene. The full length of PoPEDF cDNA is 1803 bp with an open reading frame of 1212 bp encoding a 403-amino-acid protein. This deduced protein contains an N-terminal signal peptide, a glycosylation site, a consensus serpin motif, and a 34-mer and a 44-mer fragment, all of which are very conserved in the PEDF family. PoPEDF gene exhibits a conserved exon-intron arrangement with 8 exons and 7 introns. This conserved evolutionary relationship was further confirmed by a phylogenetic analysis, where fish PEDFs and mammalian members formed a well-supported clade. Constitutive expression of PoPEDF was widely detected in many tissues. In response to UV-inactivated GCHV or poly(I:C), PEDF mRNA was upregulated in FEC cells with time. This is the first report on the transcriptional induction of PEDF in virally infected cells. (C) 2005 Elsevier Inc. All rights reserved.

Application of Inductive Logic Programming to Structure-Based Drug Design

Enot, D. and King, R. D. (2003) Application of Inductive Logic Programming to Structure-Based Drug Design. 7th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD '03). Springer LNAI 2838 p156-167

An Empirical Study of the Use of Relevance Information in Inductive Logic Programming

Srinivasan, A., King, R. D. and Bain, M.E. (2003) An Empirical Study of the Use of Relevance Information in Inductive Logic Programming. Journal of Machine Learning Research. 4(Jul):369-383

Structure based drug design with inductive logic programming

David P. Enot and Ross D. King (2003). Structure based drug design with inductive logic programming. The ACS National Meeting Spring 2003, New Orleans

The use of Inductive Logic Programming in drug design

David P. Enot and Ross D. King (2002) The use of Inductive Logic Programming in drug design. Proceedings of the 14th EuroQSAR Symposium (EuroQSAR 2002). Blackwell Publishing, p247-250

Resonant power conversion topologies for inductive charging of electrical vehicle batteries

This thesis is concerned with inductive charging of electric vehicle batteries. Rectified power form the 50/60 Hz utility feeds a dc-ac converter which delivers high-frequency ac power to the electric vehicle inductive coupling inlet. The inlet configuration has been defined by the Society of Automotive Engineers in Recommended Practice J-1773. This thesis studies converter topologies related to the series resonant converter. When coupled to the vehicle inlet, the frequency-controlled series-resonant converter results in a capacitively-filtered series-parallel LCLC (SP-LCLC) resonant converter topology with zero voltage switching and many other desirable features. A novel time-domain transformation analysis, termed Modal Analysis, is developed, using a state variable transformation, to analyze and characterize this multi-resonant fourth-orderconverter. Next, Fundamental Mode Approximation (FMA) Analysis, based on a voltage-source model of the load, and its novel extension, Rectifier-Compensated FMA (RCFMA) Analysis, are developed and applied to the SP-LCLC converter. The RCFMA Analysis is a simpler and more intuitive analysis than the Modal Analysis, and provides a relatively accurate closed-form solution for the converter behavior. Phase control of the SP-LCLC converter is investigated as a control option. FMA and RCFMA Analyses are used for detailed characterization. The analyses identify areas of operation, which are also validated experimentally, where it is advantageous to phase control the converter. A novel hybrid control scheme is proposed which integrates frequency and phase control and achieves reduced operating frequency range and improved partial-load efficiency. The phase-controlled SP-LCLC converter can also be configured with a parallel load and is an excellent option for the application. The resulting topology implements soft-switching over the entire load range and has high full-load and partial-load efficiencies. RCFMA Analysis is used to analyze and characterize the new converter topology, and good correlation is shown with experimental results. Finally, a novel single-stage power-factor-corrected ac-dc converter is introduced, which uses the current-source characteristic of the SP-LCLC topology to provide power factor correction over a wide output power range from zero to full load. This converter exhibits all the advantageous characteristics of its dc-dc counterpart, with a reduced parts count and cost. Simulation and experimental results verify the operation of the new converter.

Magnetic superlens-enhanced inductive coupling for wireless power transfer

Mitsubishi Electric Research Laboratories, USA

An inductive reasoning model in linear and quadratic sequences

Presentamos algunos resultados de una investigación más amplia cuyo objetivo general es describir y caracterizar el razonamiento inductivo que utilizan estudiantes de tercero y cuarto de Secundaria al resolver tareas relacionadas con sucesiones lineales y cuadráticas (Cañadas, 2007). Identificamos diferencias en el empleo de algunos de los pasos considerados para la descripción del razonamiento inductivo en la resolución de dos de los seis problemas planteados a los estudiantes. Describimos estas diferencias y las analizamos en función de las características de los problemas.