Due to great value of the time constant of the integrator circuit, a hardware defined PWM (Pulse Width Modulation) signal makes it possible to build a Digital to Analog Converter (DAC) characterized by a relatively long response time. An attempt at creating the software defined PWM signal leads to increased response time of the DAC converter with a coefficient several hundred times longer than ...

The increasing use of microarray technologies is generating a large amount of data that must be processed to extract underlying gene expression patterns. Existing clustering methods could suffer from certain drawbacks. Most methods cannot automatically separate scattered, singleton and mini-cluster genes from other genes. Inclusion of these types of genes into regular clustering processes can i...

BACKGROUND Renal cell carcinoma (RCC) is one of the most common kidney cancers and is highly resistant to chemotherapy. We previously demonstrated that 5-aza-2'-deoxycytidine (DAC) could significantly increase the susceptibility of renal cell carcinoma (RCC) cells to paclitaxel (PTX) treatment in vitro, and showed the synergy of DAC and PTX against RCC. The purpose of this study is to investiga...

Microsomal arylacetamide deacetylase (DAC) competes against the activity of cytosolic arylamine N-acetyltransferase, which catalyzes one of the initial biotransformation pathways for arylamine and heterocyclic amine carcinogens in many species and tissues. Activity determination and immunoblot analysis of DAC in human target tissues for arylamine carcinogens revealed that in extrahepatic tissu...

In this paper an event-driven (ED) digital signal processing system (DSP), Analog-to-digital converter (ADC) and Digital-to-analog converter (DAC) operating in continuous-time (CT) with smart dust as the target application is presented. The benefits of the CT system compared to its conventional counterpart are lower in-band quantization noise and no requirement of a clock generator and anti-ali...

Despite the popularity of digital devices, real world signals are typically represented by analog signals. Digital control systems process real world analog signals by using an analog-to-digital converter (ADC) to convert analog signals to digital. Conversions back to analog signals are accomplished using a digital-toanalog converter (DAC). Maxim offers a complete line of precision DACs from 8 ...

Proper organ patterning depends on a tight coordination between cell proliferation and differentiation. The patterning of Drosophila retina occurs both very fast and with high precision. This process is driven by the dynamic changes in signaling activity of the conserved Hedgehog (Hh) pathway, which coordinates cell fate determination, cell cycle and tissue morphogenesis. Here we show that duri...

This paper presents the design and experimental results of a continuous-time (CT) sigma-delta (ΣΔ) modulator with data-weighted average (DWA) technology for WiMAX applications. The proposed modulator comprises a third-order active RC loop filter, internal quantizer operating at 160 MHz and three DAC circuits. A multi-bit quantizer is used to increase resolution and multi-bit non-return-to-zero ...

We have cloned a chick homologue of Drosophila dachshund (dac), termed Dach1. Dach1 is the orthologue of mouse and human Dac/Dach (hereafter referred to as Dach1). We show that chick Dach1 is expressed in a variety of sites during embryonic development, including the eye and ear. Previous work has demonstrated the existence of a functional network and genetic regulatory hierarchy in Drosophila ...

alpha1-Adrenergic agonists inhibit hyperventilation-induced bronchoconstriction (HIB) in dogs. We tested the hypothesis that alpha-agonists inhibit HIB by reducing bronchovascular leakage and edema that theoretically could cause airway obstruction. Peripheral airways were isolated by using a bronchoscope; pretreated with either methoxamine (Mx), norepinephrine (NE), or saline aerosol; and then ...