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Since the official registration of the word "Mechatronics" as a trademark by Yaskawa Electric Corporation in 1971, explosive growth has been observed in mechatronics research and product development activities. Nowadays, mechatronics and mechatronic design methodologies play increasingly important roles in computer, communication, control, and consumer product (4C) technologies. As such, it is fair to agree that mechatronics technology has profoundly affected almost all aspects of human life, particularly, of engineering realities ranging from rehabilitation devices to ground and underwater robots, and from unmanned aerial vehicles to intelligent manufacturing facilities, constituting a rapidly progressing frontline. [ABSTRACT FROM AUTHOR]

Previous modeling of thin-film batteries has primarily looked at simple discharge loads. This work examines modeling of midfrequency dynamic loads with large variation in current during repetitive loading cycles, a type of loading that is very common in microelectromechanical system (MEMS) applications. Here we show an extension of traditional modeling of thin-film batteries to account for switching and capacitive loading representing piezoelectric or electrostatic microactuation. This model captures behavior at both fast and slow timescales, including effects of short-duration, high-current spikes. We show validation of the model and introduce a cycle projection scheme that allows for over 94% reduction in numerical calculations over a full battery discharge which includes over a million cycles. [ABSTRACT FROM AUTHOR]

Trichloroetheylene (TRI) is an environmental pollutant that has been linked to congenital heart defects (CHD). Endothelial nitric oxide synthase (eNOS) generation of nitric oxide (NO) plays an important role in endothelial cell proliferation, which is considered essential for normal blood vessel growth and development. We hypothesized that TRI alters the balance of NO and superoxide anion (O2-) to impair endothelial cell proliferation. Proliferating endothelial cells were pretreated with TRI (5 μM) and then stimulated with the calcium ionophore, A23187 (5 μM), to determine changes in endothelial cell and eNOS function with respect to NO and O2- generation. Immunoblots of eNOS, phospho-eNOS at serine 1179 (S1179), and the levels of associated heat shock protein 90 (hsp90) were used to define the activation state of eNOS. The effects of TRI (0.05-100 μM) on vascular endothelial growth factor (VEGF, 0.58 nM) induced endothelial cell proliferation were determined from cell counts. TRI decreased A23187-stimulated nitrite + nitrate production from 1.99 ± 0.90 to 0.89 ± 0.51 pmol/mg protein (p < 0.05; n = 6). In controls, Lω-nitroargininemethylester (L-NAME) increased A23187-stimulated O2- production from 0.130 ± 0.089 to 0.214 ± 0.071 nmol/min/mg protein (p < 0.05; n = 5). In TRI-treated cultures, however, L-NAME decreased A23187-stimulated O2- production from 0.399 ± 0.121 to 0.199 ± 0.055 nmol/min/mg protein (p < 0.05; n = 5). TRI decreased hsp90 associated with eNOS by 46.7% and inhibited VEGF-stimulated endothelial cell proliferation by 12 to 35%. These data show that TRI alters hsp90 interactions with eNOS and induces eNOS to shift from NO to O2- generation. Our findings provide new insight into how TRI alters endothelial and eNOS function to impair VEGF-stimulated endothelial proliferation. Such changes in endothelial function may play an important role in the development of congenital heart defects. [ABSTRACT FROM AUTHOR]

An interactive computer system used for the visualization of a circular weft-knitting-machine head is described. The system consists of a series of computer packages, which the designer, sitting at the graphics display, uses to build up progressively information describing the weft-knitting machine. The computer packages use Fortran and the graphics language GINO-F and were designed by using a Digital Equipment Corporation PDP 10 computer. One of the most significant advantages of the system is that it enables the machine designer to change the display quickly, for example, to alter positions of the thread guide or the stitch draw. It is also possible to have a display of resulting yarn tensions that occur as the needle passes through the knitting cycle. Work is proceeding to develop the system to generate tapes for numerically controlled machining of the knitting cams. [ABSTRACT FROM AUTHOR]

It is difficult to design cams for high-speed circular weft-knitting machines. Either the yams break owing to high knitting tensions or the needles fail because of unsatisfactory dynamics. Non-linear cams offer a way out of this dilemma. This paper describes an investigation into the suitability of three non-linear profiles for inclusion in a computer-aided-design system. The profiles are evaluated according to the various knitting and dynamic requirements. By making the computer system interactive, the processing capability of the computer can complement the experience of the designer. [ABSTRACT FROM AUTHOR]