Animals use sensory information and memory to build internal representations of space. It has been shown that such representations extend beyond the geometry of an environment and also encode rich sensory experiences usually referred to as context. In mammals, contextual inputs from sensory cortices appear to be converging on the hippocampus as a key area for spatial representations and memory.
View Article and Find Full Text PDFRecent progress in the field of microsystems on flexible substrates raises the need for alternatives to the stiffness of classical actuation technologies. This paper reports a top-down process to microfabricate soft conducting polymer actuators on substrates on which they ultimately operate. The bending microactuators were fabricated by sequentially stacking layers using a layer polymerization by layer polymerization of conducting polymer electrodes and a solid polymer electrolyte.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
July 2013
In this work we simultaneously aim at addressing the design and fabrication of microelectromechanical systems (MEMS) for biological applications bearing actuation and readout capabilities together with adapted tools dedicated to surface functionalization at the microscale. The biosensing platform is based on arrays of silicon micromembranes with piezoelectric actuation and piezoresistive read-out capabilities. The detection of the cytochrome C protein using molecularly imprinted polymers (MIPs) as functional layer is demonstrated.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
September 2012
The advantage of using lead zirconate titanate (PbZr(0.54)Ti(0.46)O(3)) ceramics as an active material in nanoelectromechanical systems (NEMS) comes from its relatively high piezoelectric coefficients.
View Article and Find Full Text PDFIEEE Trans Ultrason Ferroelectr Freq Control
July 2009
SU-8, an epoxy-based photoresist, was introduced as the acoustical matching layer between silicon and water for lab-on-chip applications integrating acoustic characterization. Acoustical performances, including the acoustic longitudinal wave velocity and attenuation of the SU-8-based matching layer, were characterized at a frequency of 1 GHz at room temperature. The gain in echo characterization with a SU-8/SiO2 bilayer and with different nanocomposite monolayers made of SU-8 and TiO2 nanoparticles (size around 35 nm) between silicon and water was characterized as being above 10 dB in each case.
View Article and Find Full Text PDFIEEE Trans Syst Man Cybern B Cybern
October 2012
Biological vision systems explore their environment via allocating their visual resources to only the interesting parts of a scene. This is achieved by a selective attention mechanism that controls eye movements. The data thus generated is a sequence of subimages of different locations and thus a sequence of features extracted from those images - referred to as attentional sequence.
View Article and Find Full Text PDFThe purpose of this examination was to observe the effects of folic acid (FA) on methotrexate (MTX)-induced derangements in the fallopian tubes. Investigators in this study sought to explore whether MTX-induced dysfunction in the fallopian tubes would be lessened by the addition of FA to MTX treatment. For this study, 18 albino Wistar rats were randomly divided into 6 groups, each of which comprised 3 rats; 0.
View Article and Find Full Text PDFEnviron Monit Assess
July 2007
Objective: This study was done to estimate whether heavy metals in the air may affect endometrial chemical composition.
Materials And Methods: A total of 30 albino Wistar rats were employed and randomly divided into three groups. The rats of Group 1 and 2 were acutely and sub-chronically exposed to the gas form of heavy metals, respectively.
Eur J Obstet Gynecol Reprod Biol
August 2006
Objective: The following study was designed to examine possible DNA damage levels in peripheral blood leukocytes, using the alkaline Comet assay, isolated from postmenopausal women undergoing osteoporosis treatment.
Study Design: Thirty-two postmenopausal women were randomized into two groups of 16. A dosage of 2.
The aim of this study was to evaluate the effect of insulin on the release of vWf in vivo during an oral glucose tolerance test (OGTT) performed in normal, glucose-intolerant and diabetic subjects and in vitro on human endothelial cells. Twenty-eight subjects exhibiting risk factors for diabetes underwent an OGTT: 11 subjects proved to be normal, 7 were glucose-intolerant and 10 diabetic. In each group, the vWf and PAI-1 plasmatic levels were measured at t = 0, 30 min and 180 min after the beginning of the test.
View Article and Find Full Text PDFThe growth of Streptococcus mutans ATCC 25 175 has been studied in the presence of various sugars (sorbitol, mannitol, lycasin, sorbose and xylitol) and compared to sucrose, glucose and fructose, added to a complex and a synthetic culture medium. In these two media, the decrease in pH was related to the bacterial growth; this fact was confirmed by the dosages of the liberated lactic acid. In the complex medium, the different sugars influenced only slightly the bacterial growth, whereas in the synthetic medium the micro-organisms did not grow in the presence of sorbose, xylitol or lycasin 80/55.
View Article and Find Full Text PDF