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.     

Efficient Learning of Relational Object Class Models

We present an efficient method for learning part-based object class models from unsegmented images represented as sets of salient features. A model includes parts’ appearance, as well as location and scale relations between parts. The object class is generatively modeled using a simple Bayesian network with a central hidden node containing location and scale information, and nodes describing object parts. The model’s parameters, however, are optimized to reduce a loss function of the training error, as in discriminative methods. We show how boosting techniques can be extended to optimize the relational model proposed, with complexity linear in the number of parts and the number of features per image. This efficiency allows our method to learn relational models with many parts and features. The method has an advantage over purely generative and purely discriminative approaches for learning from sets of salient features, since generative method often use a small number of parts and features, while discriminative methods tend to ignore geometrical relations between parts. Experimental results are described, using some bench-mark data sets and three sets of newly collected data, showing the relative merits of our method in recognition and localization tasks.     

Complications after extracorporeal shock wave lithotripsy (ESWL) and methods of management of such cases

The authors presented the complications which occurred in patients after extracorporeal shock wave lithotripsy (ESWL), and discussed the methods of management of such patients. It was found that the most common complications were: renal colic, fever, "calculus route", and, less frequently, subcapsular and perirenal haematomas. In most patients conservative treatment was adequate. Some of these patients required admission to hospital and proper specialized management.     

Continuous input nonlocal games

We present a family of nonlocal games in which the inputs the players receive are continuous. We study three representative members of the family. For the first two a team sharing quantum correlations (entanglement) has an advantage over any team restricted to classical correlations. We conjecture that this is true for the third member of the family as well.