Map-based quantitative trait locus identification

Poultry gene mappers chose microsatellites as the main source of genetic markers for poultry genome mapping, similar to the marker type used for other farm animals, laboratory animals, and humans. Optimal strategies for applying DNA markers in poultry populations are discussed, including the number of markers to be used, genome representation, population structure, choice of markers, population size, statistical stringency for association between markers and quantitative trait loci (QTL), and biological verification of a linkage. It is shown that an efficient strategy should be based on a combination of a low stringent statistical test for the existence of linkage between a marker and QTL and an appropriate genetic test for the discrimination between true and false linkage. The source of the genetic variation to be used is discussed and, as an illustration, three types of resource populations are presented. The informativeness of different matings using various genotypes of the parents are considered and it appears that selection of markers based on the heterozygosity of the sire is the most efficient marker screening approach.     

Polynomial approximation of functions of matrices and applications

In solving a mathematical problem numerically, we frequently need to operate on a vector by an operator that can be expressed asf(A), whereA is anN ×N matrix [e.g., exp(A), sin(A), A^–-]. Except for very simple matrices, it is impractical to construct the matrixf (A) explicitly. Usually an approximation to it is used. This paper develops an algorithm based upon a polynomial approximation tof (A). First the problem is reduced to a problem of approximatingf (z) by a polynomial in z, where z belongs to a domainD in the complex plane that includes all the eigenvalues ofA. This approximation problem is treated by interpolatingf (z) in a certain set of points that is known to have some maximal properties. The approximation thus achieved is almost best. Implementing the algorithm to some practical problems is described. Since a solution to a linear systemAx=b isx=A ^–1 b, an iterative solution algorithm can be based upon a polynomial approximation tof (A)=A ^–1. We give special attention to this important problem.     

Chemical vapour depositedin-situ composites in the system Ti-Si-C

Chemical vapour deposited (CVD) SiC-ceramic composites were produced by adding TiCl₄ to the SiH₂Cl₂-C₄H₁₀-H₂ system previously used to prepare CVD -SiC. Experiments performed in a classical cold-wall reactor on a graphite substrate heated by Joule effect, were carried out at a constant hydrogen gas flow rate of 30 l h^–1, under atmospheric pressure and at a deposition temperature ranging from 1123–1373 K. Silicon, titanium and carbon elemental compositions were determined by electron probe microanalysis-wavelength dispersive spectrometry. Phase identifications were mainly performed by Auger electron spectroscopy and X-ray diffraction and additionally by Raman spectroscopy. Three- and two-phased materials were obtained: SiC-TiC-C, SiC-TiC and SiC-TiSi₂ with ratios 42<11. Temperature governed the dominance of the dispersed phases: lower for TiSi₂ and higher for TiC than TiC + C. At 1373 K, co-deposits were strongly textured, the -SiC [2 2 0] preferred orientation getting weaker as the deposition temperature decreased. Apparent crystallite size along the 2 2 0 direction decreased with temperature from about 15 nm to 10 nm. The deposition rate was almost independent of time and decreased with temperature from about 800 m h^–1 to 60 m h^–1. Arrhenius plots showed linear relationships with temperature and slope breaks at 1123 K, the temperature corresponding to the change of the dispersed phases in the SiC matrix.     

Nonperiodic Trigonometric Polynomial Approximation

The most common approach for approximating non-periodic function defined on a finite interval is based on considering polynomials as basis functions. In this paper we will address the non-optimallity of polynomial approximation and suggest to switch from powers of \(x\) to powers of \(\sin (px)\) where \(p\) is a parameter which depends on the dimension of the approximating subspace. The new set does not suffer from the drawbacks of polynomial approximation and by using them one can approximate analytic functions with spectral accuracy. An important application of the new basis functions is related to numerical integration. A quadrature based on these functions results in higher accuracy compared to Legendre quadrature.     

Recent progress in road and lane detection: a survey

The problem of road or lane perception is a crucial enabler for advanced driver assistance systems. As such, it has been an active field of research for the past two decades with considerable progress made in the past few years. The problem was confronted under various scenarios, with different task definitions, leading to usage of diverse sensing modalities and approaches. In this paper we survey the approaches and the algorithmic techniques devised for the various modalities over the last 5 years. We present a generic break down of the problem into its functional building blocks and elaborate the wide range of proposed methods within this scheme. For each functional block, we describe the possible implementations suggested and analyze their underlying assumptions. While impressive advancements were demonstrated at limited scenarios, inspection into the needs of next generation systems reveals significant gaps. We identify these gaps and suggest research directions that may bridge them.     

Modeling and verification of a telecommunication application using live sequence charts and the Play-Engine tool

We apply the scenario-based approach to modeling, via the language of live sequence charts (LSCs) and the Play-Engine tool to a real-world complex telecommunication service, . It allows a user to call for help from a doctor, the fire brigade, a car maintenance service, etc. These kinds of services are built on top of an embedded platform, using both new and existing service components, and their complexity stems from their distributed architecture, the various time constraints they entail, and their rapidly evolving underlying systems. A well known problem in this class of telecommunication applications is that of feature interaction, whereby a new feature might cause problems in the execution of existing features. Our approach provides a methodology for high-level modeling of telecommunication applications that can help in detecting feature interaction at early development stages. We exhibit the results of applying the methodology to the specification, animation and formal verification of the Depannage service.

Expert judgment: Some necessary conditions and an example.

Studied characteristics of expertise in situations where judges deal with multidimensional information. Psychometric criteria were advocated as being indicative of expert judgment: (a) Experts should tend to cluster variables in the same way when identifying and organizing cues; (b) expert judgment should be highly reliable (intrajudge reliability), show both convergent and discriminant validity, and be relatively free of judgmental bias when measuring cues; and (c) experts should weight and combine information in similar ways. These criteria were applied to data obtained when 3 medical pathologists rated the amount of histological signs in biopsy slides. Results show that these experts generally met the criteria, although they did not seem to weigh information similarly. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chronic in vivo nerve electrical recordings of Aplysia californica using a boron-doped polycrystalline diamond electrode

Custom diamond electrodes for in vivo, passive electrical nerve recording were developed and implanted in an intact, freely behaving Aplysia californica. A diamond electrode may have advantages for electrical recording because of its chemical stability, higher signal-to-noise ratio, and reduced biological fouling relative to traditional nerve-recording electrode materials. For example, thin stainless steel electrodes used for chronic extracellular recording in Aplysia typically last on the order of seven days in vivo. We have developed a first-generation diamond electrode with a flexible lead to withstand the complicated movements of Aplysia and to enable direct comparison with implanted stainless steel electrodes.Boron-doped polycrystalline diamond was grown onto tungsten wire substrates by hot filament chemical vapor deposition. The wires were pre-shaped into a hook (for nerve recording) or a loop (for a ground wire) and masked for selective growth on only 2–3 mm of the wire. After diamond growth, the uncoated portion of the wire substrates was removed and the intact diamond-coated hook or loop attached to a stainless steel electrical lead with conductive epoxy. After epoxy curing, these electrodes were insulated and implanted in the animal.The diamond and stainless steel electrodes were attached extracellularly to buccal nerve 2, a primary nerve for the feeding behavior of A. californica. The two electrodes were implanted adjacent to each other so that the recordings would be nearly synchronous. In vivo recordings were successfully obtained on a diamond hook electrode during a feeding behavior for up to 9 days after the implantation. The electrode remained intact for a total of 28 days in the animal and upon retrieval.     

Temporal perspective on individual driver behavior using electronic records of undesirable events

This paper explores In-Vehicle Data Recorders (IVDRs) information about the count of undesirable driving events (such as hard braking, lane changing, and sharp turning) of 148 individuals. The information was logged over three years and included time stamp information about the occurrence of undesirable driving events in each trip (N = 573,238). The objective was to gain deeper understanding about the heterogeneity among drivers with respect to behavior change over time, the effect of trip duration and the distribution of events count. Our findings show that in some respects drivers are similar: for all drivers, the variance of the events count was larger than the mean, indicating that the negative binomial distribution is suitable to model the distribution of events count per trip. Most drivers (95%) had lower events rate during longer trips, suggesting that a ‘simple’ events rate index is problematic when comparing between those driving longer trips and drivers driving short trips. In addition, most drivers (87%) improved their driving behavior throughout the measurement period. However, there are important differences among drivers in terms of the frequency of behavior change and the trends in behavior over time. These findings demonstrate the need for personalized examination of individual drivers. Several tools for such personalized examination were developed and discussed in this study.     

Analysis of the instabilities related to the multiselective injection and withdrawal procedures of the advanced solar pond

This paper concerns the development of instabilities stemming from the multiselective injection and withdrawal procedures which create the stratified thermal layer of the advanced solar pond (ASP). A cascade of thin plates models the Entrance Unit, and a line sink models the Exit Unit. Two flow patterns are identified: A transient pattern and a steady state. The transient pattern may destroy the steady state flow. However, proper operations of the ASP injection and withdrawal ports may reduce or cancel the potentially destructive flow instabilities. Other topics concerned in this paper refer to the decay of turbulence in the ASP stratified layers, and differences between types of instability developed in the ASP subject to field conditions, and those developed in the ASP laboratory simulator.