Comparative study of 3D flux electrical machines with soft magnetic composite cores

This paper compares two types of three-dimensional (3D) flux electrical machines with soft magnetic composite (SMC) cores, namely claw pole and transverse flux machines. 3D electromagnetic field analysis is conducted for the computation of some important parameters and optimization of the machine structures. An Equivalent electric circuit is derived to calculate the machine performances. The analysis methods are validated by experimental results of a single phase claw pole permanent magnet machine with a SMC core. Useful conclusions are drawn from the evaluation and comparison of two machines with soft magnetic composite cores

Does prohibitin expression regulate sperm mitochondrial membrane potential, sperm motility, and male fertility?

Prohibitin (PHB) is a highly conserved major sperm mitochondrial membrane protein whose absence in somatic cells is associated with mitochondrial membrane depolarization and increased generation of reactive oxygen species (ROS). Our recent findings suggest that high levels of oxidants in human semen may contribute to male infertility and that sperm motility could be the earliest and most sensitive indicator of oxidative damage. Based on PHB's roles in mitochondrial sub-compartmentalization and respiratory chain assembly, we examine sperm PHB expression and mitochondrial membrane potential (MITO) in infertile men with poor sperm motility (asthenospermia, A) and/or low sperm concentrations (oligoasthenospermia, OA). Here, we demonstrate that MITO is significantly lower in sperm from A and OA subjects than in normospermic (N) subjects; the decrease is more severe for OA than for A subjects. PHB expression is also significantly lower in sperm from A and OA subjects. Significantly positive correlations are found among PHB expression, MITO, and sperm motility in normospermic, asthenospermic, and oligoasthenospermic subjects. Collectively, our observations lead to the hypothesis that PHB expression is an indicator of sperm quality in infertile men, and that it regulates sperm motility via an alteration in MITO and increased ROS levels. © Copyright 2012, Mary Ann Liebert, Inc.published_or_final_versio

Low-Cost Battery Monitoring by Converter-Based Electrochemical Impedance Spectroscopy

The use of batteries and other electrochemical devices in modern power systems is rapidly increasing, with stricter requirements in terms of cost, efficiency and reliability. Innovative monitoring solutions are therefore urged to allow a successful development of a wide range of emerging applications, including electric vehicles and large-scale energy storage to support renewable energy generation. Presently, a huge gap still exists between the accurate and sophisticated monitoring techniques commonly employed in laboratory tests, on the one hand, and the simple and rough solutions available in most commercial applications, on the other hand. The objective of this paper is therefore to contribute to the development of low-cost but accurate solutions for commercial battery condition monitoring, by proposing an embedded system that combines real-time digital signal processing with the high computational power and user friendly interface of a modern computer, at a cost comparable to a simple micro-controller. In more detail, the paper focuses on electrochemical impedance spectroscopy on a battery performed by a DC-DC power converter, and it explains how the proposed low-cost off-the-shelf hardware can control the converter, acquire the measurement signals, accurately process them in the time and frequency domains, and estimate the result uncertainty in real-time, which is necessary to promptly and reliably detect any variation in the battery condition

Case study in six sigma methadology : manufacturing quality improvement and guidence for managers

This article discusses the successful implementation of Six Sigma methodology in a high precision and critical process in the manufacture of automotive products. The Six Sigma define–measure–analyse–improve–control approach resulted in a reduction of tolerance-related problems and improved the first pass yield from 85% to 99.4%. Data were collected on all possible causes and regression analysis, hypothesis testing, Taguchi methods, classification and regression tree, etc. were used to analyse the data and draw conclusions. Implementation of Six Sigma methodology had a significant financial impact on the profitability of the company. An approximate saving of US$70,000 per annum was reported, which is in addition to the customer-facing benefits of improved quality on returns and sales. The project also had the benefit of allowing the company to learn useful messages that will guide future Six Sigma activities

The Teleost Retina as a Model for Developmental and Regeneration Biology

Retinal development in teleosts can broadly be divided into three epochs. The first is the specification of cellular domains in the larval forebrain that give rise to the retinal primordia and undergo early morphogenetic movements. The second is the neurogenic events within the retina proper—proliferation, cell fate determination, and pattern formation—that establish neuronal identities and form retinal laminae and cellular mosaics. The third, which is unique to teleosts and occurs in the functioning eye, is stretching of the retina and persistent neurogenesis that allows the growth of the retina to keep pace with the growth of the eye and other tissues. The first two events are rapid, complete by about 3 days postfertilization in the zebrafish embryo. The third is life-long and accounts for the bulk of retinal growth and the vast majority of adult retinal neurons. In addition, but clearly related to the retina's developmental history, lesions that kill retinal neurons elicit robust neuronal regeneration that originates from cells intrinsic to the retina. This paper reviews recent studies of retinal development in teleosts, focusing on those that shed light on the genetic and molecular regulation of retinal specification and morphogenesis in the embryo, retinal neurogenesis in larvae and adults, and injury-induced neuronal regeneration.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63365/1/zeb.2004.1.257.pd

The p38 MAPK-regulated PKD1/CREB/Bcl-2 pathway contributes to selenite-induced colorectal cancer cell apoptosis in vitro and in vivo

AbstractSupranutritional selenite has anti-cancer therapeutic effects in vivo; however, the detailed mechanisms underlying these effects are not clearly understood. Further studies would broaden our understanding of the anti-cancer effects of this compound and provide a theoretical basis for its clinical application. In this study, we primarily found that selenite exposure inhibited phosphorylation of cyclic adenosine monophosphate (cAMP)-response element binding protein (CREB), leading to suppression of Bcl-2 in HCT116 and SW480 colorectal cancer (CRC) cells. Moreover, the selenite-induced inhibitory effect on PKD1 activation was involved in suppression of the CREB signalling pathway. Additionally, we discovered that selenite treatment can upregulate p38 MAPK phosphorylation, which results in inhibition of the PKD1/CREB/Bcl-2 survival pathway and triggers apoptosis. Finally, we established a colorectal cancer xenograft model and found that selenite treatment markedly inhibits tumour growth through the MAPK/PKD1/CREB/Bcl-2 pathway in vivo. Our results demonstrated that a supranutritional dose of selenite induced CRC cell apoptosis through inhibition of the PKD1/CREB/Bcl-2 axis both in vitro and in vivo