Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Tax Perception - An Empirical Survey

This paper gives a survey of the experimental literature on the perception (bias) of individuals with respect to their own tax burden and its effect on economic decisions. Six strands of literature are discussed: (1) perception of marginal tax rates, (2) influence of tax complexity on tax perception, (3) taxation and incentives to work, (4) tax salience, (5) tax morale and fairness and (6) money illusion, perceived inflation and fiscal drag. The literature discussed contains more evidence for than against a perception bias

Hybrid fibre-optic voltage sensor for remote monitoring of electrical submersible pump motors

We report on the design and experimental evaluation of the hybrid fiber Bragg grating (FBG) piezoelectric voltage sensor developed specifically for remote monitoring of electrical submersible pump (ESP) motors. Unlike a previously reported transducer based on a single piezoelectric element, the voltage rating of the presented device could be as low as 500 V due to the use of a multilayer piezoelectric stack as the primary voltage-to-strain transducer. This enables the use of such sensors across a wider range of ESP applications, which often have subkilovolt voltage ratings. In addition to the design details, we present details of the full characterization of the device, including the hysteresis and temperature-dependence characteristics and discuss ways of eliminating or reducing these effects. We also demonstrate that the sensor can be used to simultaneously measure voltage and temperature. ¦#169;2005 Society of Photo-Optical Instrumentation Engineers

Hybrid fiber-optic current sensor for remote monitoring of electrical submersible plant

This paper gives details of the design, construction and experimental evaluation of the optical current sensor developed specifically to monitor electrical submersible pumps operating several tens of km away from an oil rig. The proposed sensor is of a hybrid construction, and uses an optical voltage-to-strain transducer to monitor a specially designed current transformer. In this application, the voltage-to-strain transducer is realized using a novel approach: it employs a fiber Bragg grating (FBG) bonded to a stack of multiple piezoelectric elements, with their respective electrodes connected in parallel. This approach greatly increases the measurement sensitivity; thus, the FBG can be interrogated using a classic scanning filter configuration rather than the interferometric technique. Moreover, since the absolute wavelength information is preserved, this brings the advantage of the simultaneous temperature measurement capability and enables the straightforward multiplexing of several sensors on one optical fiber

Temperature compensation for a piezoelectric fiber-optic voltage sensor

In this paper we demonstrate a temperature compensation technique for the previously developed hybrid voltage sensor that employs a single fiber Bragg grating (FBG) bonded to a piezoelectric stack element. The FBG is used to measure voltage-induced strain within the piezoelectric transducer, and its wavelength readings can be calibrated to recover the instantaneous voltage value. Since only the ac voltage measurement is required in the given application, the local temperature is recovered by way of discriminating between the semi-static temperature signal and the dynamic voltage signal in frequency domain using low-pass filtering. Knowing the thermal behavior of the voltage sensor, voltage readings are readily corrected using the local temperature information. The transducer was thermally cycled between 20 and 100degC, and the proposed method provided compensation of temperature induced errors from 2%/100degC down to the experimental error below 0.5% (full scale output

Design and evaluation of a pre-prototype hybrid fiber-optic voltage sensor for a remotely interrogated condition monitoring system

In this paper we give details of the design and laboratory evaluation of the pre-prototype hybrid fiber Bragg grating piezoelectric voltage sensor for a remotely interrogated condition monitoring system, such as the measurement system used for monitoring of electrical submersible pump (ESP) motors. The proposed sensor design is directed towards the upper voltage rating (5 kV) of ESP motors

Hysteresis compensation for a piezoelectric fiber optic voltage sensor

We present details of numerical techniques developed to compensate the effects of hysteresis experienced by a hybrid piezoelectric fiber optic voltage sensor. The techniques, implemented using a real-time signal processing system, are tested and their effectiveness evaluated experimentally. The best of the proposed algorithms provides phase error compensation from approximately 7 to nearly 0 deg, and allows us to perform sensor calibration to achieve accuracy better than 0.5% (full scale output)