bluuebunny/crossref_metadata_2025_split huggingface dataset:
The mechanism of emergenesis
Authors: Lykken D. T. 
Published: April 2006

Since each individual produced by the sexual process contains a unique set of genes, very exceptional combinations of genes are unlikely to appear twice even within the same family.E. O. Wilson (1978)
The intraclass correlations of monozygotic twins who were separated in infancy and reared apart (MZA twins) provide estimates of trait heritability, and the Minnesota Study of Twins Reared Apart [MISTRA: Bouchard et al. (1990), The sources of human psychological differences: the Minnesota study of twins reared apart, Science 250, 223–228] has demonstrated that MZA pairs are as similar in most respects as MZ pairs reared together. Some polygenic traits—e.g. stature, IQ, harm avoidance, negative emotionality, interest in sports—are polygenic‐additive, so pairs of relatives resemble one another on the given trait in proportion to their genetic similarity. But the existence and the intensity of other important psychological traits seem to be emergent properties of gene configurations (or configurations of independent and partially genetic traits) that interact multiplicatively rather than additively. Monozygotic (MZ) twins may be strongly correlated on such emergenic traits, while the similarity of dizygotic (DZ) twins, sibs or parent–offspring pairs may be much less than half that of MZ pairs. Some emergenic traits, although strongly genetic, do not appear to run in families. MISTRA has provided at least two examples of traits for which MZA twins are strongly correlated, and DZA pairs correlate near zero, while DZ pairs reared together (DZTs) are about half as similar as MZTs. These findings suggest that even more traits may be emergenic than those already identified. Studies of adoptees reared together (who are perhaps more common than twins reared apart) may help to identify traits that are emergenic, but that also are influenced by a common rearing environment.
Dynamics of Sheared Convective Boundary Layer Entrainment. Part II: Evaluation of Bulk Model Predictions of Entrainment Flux
Authors: Conzemius Robert J. , Fedorovich Evgeni 
Published: April 2006

Abstract
Several bulk model–based entrainment parameterizations for the atmospheric convective boundary layer (CBL) with wind shear are reviewed and tested against large-eddy simulation (LES) data to evaluate their ability to model one of the basic integral parameters of convective entrainment—the entrainment flux ratio. Test results indicate that many of these parameterizations fail to correctly reproduce entrainment flux in the presence of strong shear because they underestimate the dissipation of turbulence kinetic energy (TKE) produced by shear in the entrainment zone. It is also found that surface shear generation of TKE may be neglected in the entrainment parameterization because it is largely balanced by dissipation. However, the surface friction has an indirect effect on the entrainment through the modification of momentum distribution in the mixed layer and regulation of shear across the entrainment zone. Because of this effect, parameterizations that take into account the surface friction velocity but exclude entrainment zone shear may sufficiently describe entrainment when wind shear in the free atmosphere above the CBL is small. In this case, the surface shear acts as a proxy for the entrainment zone shear. Such parameterizations can be most useful if applied in situations where atmospheric data are insufficient for calculating entrainment zone shear. The importance of modeling a Richardson-number-limited, finite-depth entrainment zone is evidenced by the relatively accurate entrainment flux predictions by models that explicitly account for effects of entrainment zone shear, but predictions by these models are often adversely affected by the underestimation of TKE dissipation in the entrainment zone.
Extracting Envelopes of Nonzonally Propagating Rossby Wave Packets
Authors: Zimin Aleksey V. , Szunyogh Istvan , Hunt Brian R. , Ott Edward 
Published: April 2006

Abstract
Previously developed techniques that have been used to extract envelopes of Rossby wave packets are based on the assumption of zonally propagating waves. In this note a method that does not require such an assumption is proposed. The advantages of the new technique, both on analytical and real-world examples, are demonstrated.
A Comparison of Data Assimilation Methods Using a Planetary Geostrophic Model
Authors: Zaron Edward D. 
Published: April 2006

Abstract
Assimilating hydrographic observations into a planetary geostrophic model is posed as a problem in control theory. The cost functional is the sum of weighted model and data residuals. Model errors are assumed to be spatially correlated, and hydrographic station data are assimilated directly. Searches in state space and data space, for minimizing the cost functional, are compared to a direct matrix inversion algorithm in the data space.
State-space methods seek the minimizer of the cost functional by performing a preconditioned search in an N-dimensional space of state or control variables, where N is approximately 650 000 in the present calculations. Data-space methods solve the Euler–Lagrange equations for the extremum of the cost functional by working in an M-dimensional dual space, where M is the number of measurements. The following four solvers are compared: (i) an iterative state-space solver, with a naive diagonal matrix preconditioner; (ii) an iterative state-space solver, with a sophisticated preconditioner based on the inverse of the model’s dynamical operators; (iii) an iterative data-space solver, with no preconditioning; and (iv) a direct, M × M matrix inversion, data-space solver. The best solver is the iterative data-space solver, (iii), which is approximately 10 times faster than the sophisticated preconditioned state-space solver, (ii), and 100 times faster than the direct data-space solver, (iv).
United Kingdom Collaborative Randomized Trial of Neonatal Extracorporeal Membrane Oxygenation: Follow-up to Age 7 Years
Authors: McNally Helena , Bennett Charlotte C. , Elbourne Diana , Field David J. ,   for the UK Collaborative ECMO Trial Group
Published: April 2006

OBJECTIVE. The UK Collaborative ECMO trial provided an opportunity to describe mortality and morbidity associated with a neonatal ECMO policy compared with conventional management. The improved survival in the ECMO group was not offset by an increase in disability at 4 years, but the children were too young to assess educational and other longer-term impacts. The objective of this study was to assess the longer-term impact of these policies at age 7 years.METHODS. A psychologist assessed 90 of the 100 children available for follow-up without prior knowledge of treatment allocation. The assessments took place at the children's schools within 3 months of their 7th birthdays.RESULTS. Sixty-eight of 89 (76%) children recorded a cognitive level within the normal range. Learning problems were similar in the 2 groups, and there were notable difficulties with spatial and processing tasks. A higher respiratory morbidity and increased risk of behavioral problems among children treated conventionally persisted. Progressive sensorineural hearing loss was found in both groups.CONCLUSIONS. The underlying disease processes appear to be the major influence on morbidity at 7 years. The beneficial influence of an ECMO policy is still present at 7 years.
HYBRIDIZATION AND THE EVOLUTION OF PLANTS
Authors: Barber H. N. 
Published: April 2006

SummaryPolyploidy — both auto‐ and allo — may have dominated the short term evolution of plants because it increases “biochemical versatility” at the primary enzyme level. It actually creates new enzymes with different properties which may extend the range of environments in which normal and successful development may occur.. The new enzymes arise by oligomerisation of related polypeptides produced by related (homoeologous) genes (“hybrid” enzymes).Further study of polyploids may help us understand more about the control of development of the phenotype. There is evidence that the concentration of different isoenzymes changes with the development of tissues. Whether this denotes a causal connection between differentiation and enzyme production, we do not know. But the presence of isoenzymes generated by polyploidy may have allowed such controls to be made more refined and delicate and, thus, helped in ecological success. The determination of the actual amino‐acid sequences of such enzymes may, in the future, perhaps contribute to a further understanding of the role of enzyme hybridization for biochemical versatility as a factor in evolution.
ON THE TYPIFICATION OF HEXAGONIA POLLINI PER FR.
Authors: Donk M. A. 
Published: April 2006

SummaryThe author does not agree with M. E. P. K. Fidalgo's replacement of Hexagonia mori Pollini per Fr. as the type of Hexagonia Pollini per Fr. by Hexagonia crinigera Fr. Her arguments in favour of this substitution are scrutinized below and found to be untenable. The correct name for Hexagonia sensu K. Fid. is Scenidium (Kl.) ex O.K. For Hexagonia sensu Bond. & S. (not validly published) the new name Apcxona Donk is proposed.
NOMENCLATURE OF THE SUBDIVISIONS OF THE LAMIACEAE
Authors: Sanders Roger W. , Cantino Philip D. 
Published: April 2006

SummaryA list is provided of all the legitimate names available for application to subtribes, tribes, subfamilies, and segregate families of the Lamiaceae. The names Elsholtzieae, Prunelleae and Tetrachondraceae are formally validated. Also presented are earlier generically based names which are invalid or inoperative under Art. 35.2 of the Code. Correct names are provided for the familial subdivisions recognized in three widely accepted systematic treatments of the Lamiaceae. Action by the Sydney Congress that affects nomenclature of the subdivisions of families is discussed.
Suprageneric nomenclature in the Caryophyllaceae
Authors: Rabeier Richard K. , Bittrich Volker 
Published: April 2006

SummaryRabeler, R. K. & Bittrich, V.: Suprageneric nomenclature in the Caryophyllaceae. – Taxon 42: 857‐863.1993. – ISSN 0040‐0262.All known suprageneric names within the Caryophyllaceae are listed.
A new family of life distributions
Authors: Birnbaum Z.W. , Saunders S.C. 
Published: April 2006

SummaryA new two parameter family of life length distributions is presented which is derived from a model for fatigue. This derivation follows from considerations of renewal theory for the number of cycles needed to force a fatigue crack extension to exceed a critical value. Some closure properties of this family are given and some comparisons made with other families such as the lognormal which have been previously used in fatigue studies.
Negative binomial processes
Authors: Barndorff-Nielsen Ole , Yeo G. F. 
Published: April 2006

SummaryThis paper is concerned with negative binomial processes which are essentially mixed Poisson processes whose intensity parameter is given by the sum of squares of a finite number of independently and identically distributed Gaussian processes. A study is made of the distribution of the number of points of a k-dimensional negative binomial process in a compact subset of Rk, and in particular in the case where the underlying Gaussian processes are independent Ornstein-Uhlenbeck processes when more detailed results may be obtained.
On survival probabilities and extinction times for some branching processes
Authors: Pollak Edward 
Published: April 2006

SummaryWe consider branching processes for which the first three moments of the distribution of offspring exist. Let f(t) andz be, respectively, the generating function of the distribution of offspring and the smallest positive root of the equation f(t) = t. Then if M = f'(z) and fn(t) is equal to the generating function of the distribution of nth generation descendants of a single individual, it is known that, quite generally, (z – fn(0)) / Mn tends toward a constant as n increases. A method is derived for obtaining upper and lower bounds for this constant, which gives an exact solution when there is a geometric distribution of offspring and good bounds when there are Poisson or negative binomial offspring distributions. With some further calculations, one can also obtain finite upper and lower bounds for the mean time to extinction of a line descended from an individual, given there is extinction. These bound apply even ifzis less than 1. Numerical values are given for the Poisson and negative binomial cases.
A proof of optimality for age replacement policies
Authors: Berg Menachem 
Published: April 2006

A well-known maintenance procedure for stochastically failing units is the age replacement policy (ARP). Under the ARP a unit is replaced on failure, or when it reaches a predetermined critical age.In previous papers concerned with this procedure the authors searched for the optimal critical age to minimize the objective function under discussion. The purpose of this paper is to prove that the ARP itself is the optimal decision rule amongst all reasonable policies.
On possible rates of growth of age-dependent branching processes with immigration
Authors: Grey D. R. 
Published: April 2006

It is shown that if ϕ is a given function out of a large class satisfying a certain regularity condition, then a supercritical age-dependent branching process {Z(t)} exists with deterministic immigration and given life-length and family-size distributions such that Z(t)/(eat ϕ(t)) converges in probability to a non-zero constant, a being the appropriate Malthusian parameter.As an easy corollary one discovers the asymptotic behaviour of some processes with random immigration.
A limit theorem for patch sizes in a selectively-neutral migration model
Authors: Sawyer Stanley 
Published: April 2006

Assume a population is distributed in an infinite lattice of colonies in a migration and random mating model in which all individuals are selectively equivalent. In one and two dimensions, the population tends in time to consolidate into larger and larger blocks, each composed of the descendants of a single initial individual. Let N(t) be the (random) size of a block intersecting a fixed colony at time t. Then E[N(t)] grows like √t in one dimension, t/log t in two, and t in three or more dimensions. On the other hand, each block by itself eventually becomes extinct. In two or more dimensions, we prove that N(t)/E[N(t)] has a limiting gamma distribution, and thus the mortality of blocks does not make the limiting distribution of N(t) singular. Results are proven for discrete time and sketched for continuous time.If a mutation rate u > 0 is imposed, the ‘block structure' has an equilibrium distribution. If N(u) is the size of a block intersecting a fixed colony at equilibrium, then as u → 0 N(u)/E[N(u)] has a limiting exponential distribution in two or more dimensions. In biological systems u ≈ 10–6 is usually quite small.The proofs are by using multiple kinship coefficients for a stepping stone population.
A representation for the limiting random variable of a branching process with infinite mean and some related problems
Authors: Cohn Harry , Pakes Anthony G. 
Published: April 2006

It is known that for a Bienaymé– Galton–Watson process {Zn} whose mean m satisfies 1 < m < ∞, the limiting random variable in the strong limit theorem can be represented as a random sum of i.i.d. random variables and hence that convergence rate results follow from a random sum central limit theorem.This paper develops an analogous theory for the case m = ∞ which replaces ‘sum' by ‘maximum'. In particular we obtain convergence rate results involving a limiting extreme value distribution. An associated estimation problem is considered.
The limiting behaviour of the maximal spacing generated by an i.i.d. sequence of Gaussian random variables
Authors: Deheuvels Paul 
Published: April 2006

Let Mn be the maximal spacing generated in the sample's range by Χ1,· ··, Χ n, independent and identically distributed Gaussian N(0, 1) random variables. We obtain the limiting distribution of and show that according to whether ε> 0 or ε < 0.
A note on the probability of extinction in a class of population-size-dependent Galton-Watson processes
Authors: Höpfner R. 
Published: April 2006

In a class of population-size-dependent Galton-Watson processes where extinction does not occur with probability 1 we describe the rate of decay of qi (the probability that the process starting from i ancestors will become extinct) as the number i of ancestors increases.The results are related to the asymptotic behavior of the Green's function of the critical Galton-Watson process with immigration.
Modelling the flow of coalescing data streams through a processor
Authors: Anantharam V. 
Published: April 2006

In a data processing network, two data streams A and B arrive at a node independently at the same Poisson rate λ. Service at exponential rate µ can take place iff there is at least one of each of A and B present. The output is the combined processed data AB. We consider models of this situation with finite buffers, with infinite buffers and with finite buffers for the excess of each input type over the other. We apply the filtering theory for point process functionals of a Markov chain to study whether the output flow is Poisson in equilibrium. The motivation is to examine, if the output is to subsequently be processed by a queueing system, whether it can be treated as an independent Poisson input to that system.A result of independent interest is that a subset of transitions of a countable-state Markov process does not yield a Poisson process when counted, if the rate matrix of counted transitions is nilpotent, and we prove a generalization of Pakes' lemma for countable-state Markov chains.
Approximate distributions of Student's t-statistics for autoregressive coefficients calculated from regression residuals
Authors: Durbin J. 
Published: April 2006

We consider a multiple regression model in which the regressors are Fourier cosine vectors. These regressors are intended as approximations to ‘slowly changing' regressors of the kind often found in time series regression applications. The errors in the model are assumed to be generated by a special type of autoregressive model defined so that the regressors are eigenvectors of the quadratic forms occurring in the exponent of the probability density of the errors. This autoregression is intended as an approximation to the usual stationary autoregression. Both approximations are adopted for the sake of mathematical convenience.Student's t-statistics are constructed for the autoregressive coefficients in a manner analogous to ordinary regression. It is shown that these statistics are distributed as Student's t to the first order of approximation, that is with errors in the density of order T−1/2, where T is the sample size, while the squares of the statistics are distributed as the square of Student's t to the second order of approximation, that is with errors in the density of order Τ–1.
Distribution of the number of alleles in multigene families
Authors: Griffiths R. C. 
Published: April 2006

The distribution of the number of alleles in samples fromrchromosomes is studied. The stochastic model used includes gene conversion within chromosomes and mutation at loci on the chromosomes. A method is described for simulating the distribution of alleles and an algorithm given for computing lower bounds for the mean number of alleles.A formula is derived for the expected number of samples fromrchromosomes which contain the allele type of a locus chosen at random.
Shape measurements of live pigs using 3-D image capture
Authors: McFarlane N. J. B. , Wu J. , Tillett R. D. , Schofield C. P. , Siebert J. P. , Ju X. 
Published: April 2006

AbstractA photogrammetric stereo imaging system was used to capture 3-D models of live pigs, and quantitative shape measurements were extracted from cross sections of the models. Stereo images were captured of 32 pigs, divided into high-lysine and low-lysine diet groups, and 3-D models were built from the images. Each pig was imaged once per week for 14 weeks. After slaughter, 10 of the pigs were dissected for muscle and fat measurements. A sequence of algorithms was applied to the 3-D models: differential geometry to reveal surface curvature features and detect the spine; manual landmark placement; fitting a curve to the spine; determining the vertical axis of the body; placing a slice plane across the abdomen close to the P2 position; extracting a cross section; and fitting a shape model to the cross section. Differential geometry revealed many qualitative features of the musculature. The spine was a line of minimum curvature along the back. The high-lysine pigs had higher height-to-width ratios and flatter backs than the low-lysine pigs. The dissected total muscle mass had a -0·66 correlation with the flatness-of-back shape parameter, and a 0·64 correlation with weight.
A study on associations between PrP genotypes and meat traits in French sheep breeds
Authors: Vitezica Z. G. , Moreno C. R. , Bouix J. , Barillet F. , Perret G. , Elsen J. M. 
Published: April 2006

AbstractIn this study the potential association of PrP genotypes with meat traits has been investigated. The data included young rams from individual testing stations of three breeds: Ile de France, Préalpes du Sud and Blanc du Massif Central. These breeds were chosen due to their large number of available animals (with performance records and PrP genotypes) and their differential ARR haplotype frequency. Two analyses differing in the PrP genotype classes considered were carried out. Firstly, animals were categorized into three classes: ARR homozygous, ARR heterozygous, and animals without the ARR haplotype. The data for this analysis included 725, 534 and 832 animals for Ile de France, Préalpes du Sud and Blanc du Massif Central breeds, respectively. Secondly, as the two predominant haplotypes in these breeds are ARR and AR- (and AR- includes ARQ and ARH haplotypes), the effect of substituting 1 or 2 ARR haplotypes for AR- haplotypes was studied. These comparisons involved three genotype classes: ARR homozygous, ARR/AR-, and AR-homozygous. The data for this analysis included 532, 509 and 620 animals of Ile de France, Préalpes du Sud and Blanc du Massif Central breeds, respectively. Meat traits were analysed using an animal model (where the PrP genotype was included as a fixed effect) and they included growth rate, ultrasonic fat depth, and ultrasonic muscle depth. The results of this study indicate no evidence of association between PrP genotypes and the meat traits studied in these sheep breeds.