In this paper, a CMOS OTA with a wide input voltage range and linearly tunable transconductance gain (gm) is presented. To achieve the linear control of transconductance, the bias current (IB) is squared by using the current squarer circuit before applying it into the main CMOS OTA. In addition, the source degeneration technique is used to extend the input voltage range. The frequency response ...

The subject of the research is the application of the methods of fluorescence anisotropy measurements to study the interaction between human serum albumin (HSA) and toxins and selected medicines (ibuprofen, warfarin, flurbiprofen). Optical spectroscopic methods are useful tools for the study of biologically active compounds. Determining binding intensity of ochratoxin A (OTA) to albumin may be ...

Ochratoxin A (OTA) is a naturally occurring fungal metabolite produced by some species of Aspergillus and Penicillium. OTA being nephrotoxic, carcinogenic, hepatotoxic and immunosuppressive imparts many human and animal health hazards. In this study OTA production was observed at different temperatures (5oC, 10oC, 20oC, 30oC and 40oC) in three substrates (corn, rice and wheat) by A. ochraceus a...

Aspergillus steynii and Aspergillus westerdijkiae are the main ochratoxin A (OTA) producing species of Aspergillus section Circumdati. Due to its recent description, few data are available about the influence of ecophysiological factors on their growth and OTA production profiles. In this work, the effect of temperature (20, 24 and 28 °C) and water activity (aw) (0.928, 0.964 and 0.995) on grow...

The operational amplifiers (OPAMP) are basic building blocks in implementing a variety of analog circuits such as amplifiers, filters, integrators, differentiators, summers, oscillators etc. OPAMPs work well for lowfrequency applications, such as audio and video systems. For higher frequencies, however, OPAMP designs become difficult due to their frequency limit. At those high frequencies, oper...

The aims of the current study were to determine the half-lethal concentration of ochratoxin A (OTA) as well as the levels of lactate dehydrogenase release and DNA fragmentation induced by OTA in primary porcine fibroblasts, and to examine the role of α-tocopherol in counteracting its toxicity. Cells showed a dose-, time- and origin-dependent (ear vs. embryo) sensitivity to ochratoxin A. Pre-inc...

this paper investigates the relationship between the lagos megacity and ota township, a small township onits periphery. the study examines linkages between and lagos in terms of growth, urban development as well as mobility. 553 questionnaires were administered to household heads across the 12 residential districts of ota township. survey was carried out by systematic random sampling. classifie...

In order to manage risk of ochratoxin A (OTA) in foods, we re-evaluated the tolerable daily intake (TDI), derived the negligible cancer risk intake (NCRI), and conducted a probabilistic risk assessment. A new approach was developed to derive 'usual' probabilistic exposure in the presence of highly variable occurrence data, such as encountered with low levels of OTA. Canadian occurrence data wer...

An impedimetric label-free immunosensor on disposable screen-printed carbon electrodes (SPCE) for quantitative determination of Ochratoxin A (OTA) has been developed. After modification of the SPCE surface with gold nanoparticles (AuNPs), the anti-OTA was immobilized on the working electrode through a cysteamine layer. After each coating step, the modified surfaces were characterized by cyclic ...

Several over-the-air (OTA) test methods have been proposed to characterize the radiated performance of multiple input multiple output (MIMO) devices. Knowing that antenna gain and spatial correlation are important factors to system performance, it has become necessary to include OTA testing of MIMO antenna performance. This paper will discuss three predominant OTA test methods including the two...