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.     

Charakterisierung und Störstoffanalyse von rückgewonnenen Stoffströmen aus Wärmedämmverbundsystemen

Due to the growing energy requirements, the proportion of external thermal insulation composite systems (ETICS) installed has increased significantly during the past 50 years. Due to the longevity of these systems, ETICS waste is currently accumulating. Owing to the complex construction as well as a multitude of differently installed materials and substances of the past generations, there are many uncertainties and problems with the clean and low-pollutant processing of such systems. In the frame of this work, the ETICS were processed and sorted before being screened for ingredients or pollutants as well as for the purity of the recovered material fractions.     

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.

Orthographic Structure Versus Morphological Structure: Principles of Lexical Organization in a Given Language.

Most models of visual word recognition in alphabetic orthographies assume that words are lexically organized according to orthographic similarity. Support for this is provided by form-priming experiments that demonstrate robust facilitation when primes and targets share similar sequences of letters. The authors examined form-orthographic priming effects in Hebrew, Arabic, and English. Hebrew and Arabic have an alphabetic writing system but a Semitic morphological structure. Hebrew morphemic units are composed of noncontiguous phonemic (and letter) sequences in a given word. Results demonstrate that form-priming effects in Hebrew or Arabic are unreliable, whereas morphological priming effects with minimal letter overlap are robust. Hebrew bilingual subjects, by contrast, showed robust form-priming effects with English material, suggesting that Semitic words are lexically organized by morphological rather than orthographic principles. The authors conclude that morphology can constrain lexical organization even in alphabetic orthographies and that visual processing of words is first determined by morphological characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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)     

Mechanical characterisation of a bone defect model filled with ceramic cements

Ceramic bone substitute materials are often used to fill defects in comminuted articular fractures. In an in vivo study [1], calcium phosphate cements have been injected into highly loaded slot defects in the proximal tibial metaphysis. During healing, cracks were formed mostly in the proximal anterior aspect of the implanted cement and wedge-like gaps formed between the tibial plateau and the cement. Mechanical ex vivo tests were done to investigate the mechanical competence of the bone cement in such a defect situation. Entirely filled defects were loaded with up to 4.5 kN until they failed. Cyclic loading of the proximal tibiae caused micro fragmentation of the cement after 1000 cycles at 1.5-2.0 kN load. This aspect was comparable to cement fragmentation observed in vivo. Large defects in highly loaded areas should therefore additionally be stabilised with metallic implants. The ceramic cement can only be used as a filler material, which can be replaced by new bone upon resorption.