@article{2524,
abstract = {Alpha-ketoglutamate (α-KG) reductive amination activity in rat brain was found to be mostly absorbed with an antibody against liver glutamate dehydrogenase. With this and anti-glutamine synthetase antibodies, α-KG reductive amination activity was immunocytochemically shown to coexist with glutamine synthetase activity in astrocytes. The results suggest that astrocytes de novo synthesize glutamate from α-KG and ammonia, and metabolize it to glutamine.},
author = {Kaneko, Takeshi and Ryuichi Shigemoto and Mizuno, Noboru},
journal = {Brain Research},
number = {1},
pages = {160 -- 164},
publisher = {Elsevier},
title = {{Metabolism of glutamate and ammonia in astrocyte an immunocytochemical study}},
doi = {10.1016/0006-8993(88)90069-8},
volume = {457},
year = {1988},
}
@misc{4315,
author = {Coyne, Jerry A and Nicholas Barton},
booktitle = {Nature},
pages = {485 -- 486},
publisher = {Nature Publishing Group},
title = {{What do we know about speciation ?}},
doi = {10.1038/331485a0},
volume = {331},
year = {1988},
}
@misc{4316,
author = {Nicholas Barton and Jones, Steve},
booktitle = {Nature},
pages = {597 -- 597},
publisher = {Nature Publishing Group},
title = {{Molecular evolutionary genetics}},
doi = {10.1038/332597a0},
volume = {332},
year = {1988},
}
@inbook{4317,
author = {Nicholas Barton},
booktitle = {Analytical biogeography},
editor = {Myers, Alan A and Giller, Paul S},
pages = {185 -- 218},
publisher = {Chapman Hall},
title = {{Speciation}},
year = {1988},
}
@misc{4318,
author = {Nicholas Barton and Jones, Steve and Mallet, James L},
booktitle = {Nature},
pages = {13 -- 14},
publisher = {Nature Publishing Group},
title = {{No barriers to speciation}},
doi = {10.1038/336013a0},
volume = {336},
year = {1988},
}
@article{3655,
author = {Dallas, John F and Nicholas Barton and Dover, Gabriel A.},
journal = {Molecular Biology and Evolution},
number = {6},
pages = {660 -- 674},
publisher = {Oxford University Press},
title = {{Interracial rDNA variation in the grasshopper Podisma pedestris}},
volume = {5},
year = {1988},
}
@article{4090,
abstract = {In this paper we study the problem of polygonal separation in the plane, i.e., finding a convex polygon with minimum number k of sides separating two given finite point sets (k-separator), if it exists. We show that for k = Θ(n), is a lower bound to the running time of any algorithm for this problem, and exhibit two algorithms of distinctly different flavors. The first relies on an O(n log n)-time preprocessing task, which constructs the convex hull of the internal set and a nested star-shaped polygon determined by the external set; the k-separator is contained in the annulus between the boundaries of these two polygons and is constructed in additional linear time. The second algorithm adapts the prune-and-search approach, and constructs, in each iteration, one side of the separator; its running time is O(kn), but the separator may have one more side than the minimum.},
author = {Herbert Edelsbrunner and Preparata, Franco P},
journal = {Information and Computation},
number = {3},
pages = {218 -- 232},
publisher = {Elsevier},
title = {{Minimum polygonal separation}},
doi = {10.1016/0890-5401(88)90049-1},
volume = {77},
year = {1988},
}
@article{4091,
abstract = {An X-ray probe through a polygon measures the length of intersection between a line and the polygon. This paper considers the properties of various classes of X-ray probes, and shows how they interact to give finite strategies for completely describing convex n-gons. It is shown that (3n/2)+6 probes are sufficient to verify a specified n-gon, while for determining convex polygons (3n-1)/2 X-ray probes are necesssary and 5n+O(1) sufficient, with 3n+O(1) sufficient given that a lower bound on the size of the smallest edge of P is known.},
author = {Herbert Edelsbrunner and Skiena,Steven S},
journal = {SIAM Journal on Computing},
number = {5},
pages = {870 -- 882},
publisher = {SIAM},
title = {{Probing convex polygons with X-Rays}},
doi = {10.1137/0217054 },
volume = {17},
year = {1988},
}
@inproceedings{4096,
author = {Herbert Edelsbrunner},
pages = {201 -- 213},
publisher = {Springer},
title = {{Geometric structures in computational geometry}},
doi = {10.1007/3-540-19488-6_117},
volume = {317},
year = {1988},
}
@inproceedings{4097,
abstract = {Arrangements of curves in the plane are of fundamental significance in many problems of computational and combinatorial geometry (e.g. motion planning, algebraic cell decomposition, etc.). In this paper we study various topological and combinatorial properties of such arrangements under some mild assumptions on the shape of the curves, and develop basic tools for the construction, manipulation, and analysis of these arrangements. Our main results include a generalization of the zone theorem of [EOS], [CGL] to arrangements of curves (in which we show that the combinatorial complexity of the zone of a curve is nearly linear in the number of curves), and an application of (some weaker variant of) that theorem to obtain a nearly quadratic incremental algorithm for the construction of such arrangements.},
author = {Herbert Edelsbrunner and Guibas, Leonidas and Pach, János and Pollack, Richard and Seidel, Raimund and Sharir, Micha},
pages = {214 -- 229},
publisher = {Springer},
title = {{Arrangements of curves in the plane - topology, combinatorics, and algorithms}},
doi = {10.1007/3-540-19488-6_118},
volume = {317},
year = {1988},
}
@article{2521,
author = {Nishimura, Masaki and Ryuichi Shigemoto and Matsubayashi, K and Mimori, Y and Kameyama, Masakuni},
journal = {Clinical Neurology},
number = {11},
pages = {1441 -- 1444},
publisher = {Societas Neurologica Japonica},
title = {{Meningoencephalitis during the pre-icteric phase of hepatitis A - a case report}},
volume = {27},
year = {1987},
}
@article{4319,
abstract = {The grasshopper Podisma pedestris contains two chromosomal races, which differ by a Robertsonian fusion between the sex chromosome and an autosome, and which meet in a narrow hybrid zone in the Alpes Maritimes. DNA content variation across this hybrid zone was investigated by optical densitometry of Feulgen stained spermatids. Spermatids from males with the unfused sex chromosome stain more strongly than those from males with the fused chromosome. The difference between the karyotypes is greater in the centre of the hybrid zone, suggesting that it is not a pleiotropic effect of the fusion itself, but is due instead to differences at closely linked loci.},
author = {Westerman, Michael and Nicholas Barton and Hewitt, Godfrey M},
journal = {Heredity},
pages = {221 -- 228},
publisher = {Nature Publishing Group},
title = {{Differences in DNA content between two chromosomal races of the grasshopper Podisma pedestris}},
doi = {10.1038/hdy.1987.36},
volume = {58},
year = {1987},
}
@article{4320,
abstract = {Bosonic field theories may be formulated in terms of stochastic differential equations. The characteristic long term behaviour of these systems is a decay into the global minimum of their Hamiltonian. If local minima exist, the rate of this decay is determined by instanton effects. We calculate the decay rate and perform computer simulations on a 1 + 1 dimensional model to test the instanton approximation. We find the instanton approximations to be in very good agreement with the simulation results.
Copyright © 1987 Published by Elsevier B.V.},
author = {Rouhani, Shahin and Nicholas Barton},
journal = {Physica A},
number = {1-2},
pages = {220 -- 226},
publisher = {Elsevier},
title = {{Instantons and stochastic quantization}},
doi = {10.1016/0378-4371(87)90064-1},
volume = {143},
year = {1987},
}
@article{4322,
abstract = {A method is developed for calculating the probability of establishment of an allele which is favoured in some places, but not others, in a large subdivided population. This method is quite general, and could be used to calculate the chance that any system which is linear near an absorbing boundary will move away from that boundary. The results are applied to a population distributed along one dimension. Only mutants which arise within a distance σ/ √2s of the region in which they are favoured stand an appreciable chance of establishment. The net chance of establishment of mutations distributed randomly across the habitat will be decreased by gene flow if selection against them is sufficiently strong. However, if the mutations are only weakly deleterious outside some limited region, gene flow may increase the net chance of establishment.},
author = {Nicholas Barton},
journal = {Genetical Research},
number = {1},
pages = {35 -- 40},
publisher = {Cambridge University Press},
title = {{The probability of establishment of an advantageous mutation in a subdivided population}},
doi = {10.1017/S0016672300023314},
volume = {50},
year = {1987},
}
@inproceedings{3514,
abstract = {We consider the problem of obtaining sharp (nearly quadratic) bounds for the combinatorial complexity of the lower envelope (i.e. pointwise minimum) of a collection of n bivariate (or generally multi-variate) continuous and "simple" functions, and of designing efficient algorithms for the calculation of this envelope. This problem generalizes the well-studied univariate case (whose analysis is based on the theory of Davenport-Schinzel sequences), but appears to be much more difficult and still largely unsolved. It is a central problem that arises in many areas in computational and combinatorial geometry, and has numerous applications including generalized planar Voronoi diagrams, hidden surface elimination for intersecting surfaces, purely translational motion planning, finding common transversals of polyhedra, and more. In this abstract we provide several partial solutions and generalizations of this problem, and apply them to the problems mentioned above. The most significant of our results is that the lower envelope of n triangles in three dimensions has combinatorial complexity at most O(n2α(n)) (where α(n) is the extremely slowly growing inverse of Ackermann's function), that this bound is tight in the worst case, and that this envelope can be calculated in time O(n2α(n)).},
author = {Herbert Edelsbrunner and Pach, János and Schwartz, Jacob T and Sharir, Micha},
pages = {27 -- 37},
publisher = {IEEE},
title = {{On the lower envelope of bivariate functions and its applications}},
doi = {10.1109/SFCS.1987.44},
year = {1987},
}
@article{3656,
abstract = {We have analysed the role of sampling drift in inducing shifts between alternative adaptive peaks, in small and rapidly growing populations. Using a simple model of disruptive selection on a polygenic character, we calculate the net probabilityofapeakshift. If the growth rate is high, theprobabilityofashiftina growing population is insensitive to selection on the character. Assuming that the character is effectively neutral during the brief initial increase, we find that theprobabilityofapeakshift is given by theprobabilityof finding a standard normal variate greater than √2ΔV where ΔV is the reduction in additive genetic variance during the growth period. This result holds for arbitrary pattern of increase in size, provided that the rate of increase is high enough for selection to be negligible, and the character depends on a large number of loci. Comparing theprobabilityofpeakshiftsin founding populations with the rate ofshiftsin static and allopatric populations it appears that although strongly selected shifts are only likely to occur ina growing population, a static population is a more congenial setting for adaptive shifts.},
author = {Rouhani, Shahin and Nicholas Barton},
journal = {Journal of Theoretical Biology},
number = {1},
pages = {51 -- 62},
publisher = {Elsevier},
title = {{The probability of peak shifts in a founder population}},
doi = {10.1016/S0022-5193(87)80100-5},
volume = {126},
year = {1987},
}
@article{3657,
abstract = {Shifts between adaptive peaks, caused by sampling drift, are involved in both speciation and adaptation via Wright's “shiftingbalance.” We use techniques from statistical mechanics to calculate the rate of such transitions for apopulation in a single panmictic deme and for apopulation which is continuously distributed over one- and two-dimensional regions. This calculation applies in the limit where transitions are rare. Our results indicate that stochastic divergence is feasible despite free gene flow, provided that neighbourhood size is low enough. In two dimensions, the rate of transition depends primarily on neighbourhood size N and only weakly on selection pressure (≈sk exp(− cN)), where k is a number determined by the local population structure, in contrast with the exponential dependence on selection pressure in one dimension (≈exp(− cN √s)) or in a single deme (≈exp(− cNs)). Our calculations agree with simulations of a single deme and a one-dimensional population.},
author = {Rouhani, Shahin and Nicholas Barton},
journal = {Theoretical Population Biology},
number = {3},
pages = {465 -- 492},
publisher = {Academic Press},
title = {{Speciation and the "shifting balance" in a continuous population}},
doi = {10.1016/0040-5809(87)90016-5},
volume = {31},
year = {1987},
}
@article{3658,
abstract = {Females of the grasshopper Podisima pedestris were collected from the middle of a hybrid zone between two chromosomal races in the Alpes Maritimes. They had already mated in the field, and could therefore lay fertilised eggs in the laboratory. The embryos were karyotyped, and found to contain an excess of chromosomal homozygotes. No evidence of assortative mating was found from copulating pairs taken in the field. The excess appears to have been caused by a combination of multiple insemination and assortative fertilisation. The genetics of the assortment, and the implications for the evolution of reproductive isolation are discussed.},
author = {Hewitt, Godfrey M and Nichols, R. A. and Nicholas Barton},
journal = {Heredity},
number = {3},
pages = {457 -- 466},
publisher = {Nature Publishing Group},
title = {{Homogamy in a hybrid zone in the alpine grasshopper Podisma pedestris}},
doi = {10.1038/hdy.1987.156},
volume = {59},
year = {1987},
}
@article{3659,
author = {Charlesworth, Brian and Coyne, Jerry A and Nicholas Barton},
journal = {American Naturalist},
number = {1},
pages = {113 -- 146},
publisher = {University of Chicago Press},
title = {{The relative rates of evolution of sex chromosomes and autosomes.}},
volume = {130},
year = {1987},
}
@article{3660,
abstract = {The maintenance of polygenic variability by a balance between mutation and stabilizing selection has been analysed using two approximations: the ‘Gaussian’ and the ‘house of cards’. These lead to qualitatively different relationships between the equilibrium genetic variance and the parameters describing selection and mutation. Here we generalize these approximations to describe the dynamics of genetic means and variances under arbitrary patterns of selection and mutation. We incorporate genetic drift into the same mathematical framework.
The effects of frequency-independent selection and genetic drift can be determined from the gradient of log mean fitness and a covariance matrix that depends on genotype frequencies. These equations describe an ‘adaptive landscape’, with a natural metric of genetic distance set by the covariance matrix. From this representation we can change coordinates to derive equations describing the dynamics of an additive polygenic character in terms of the moments (means, variances, …) of allelic effects at individual loci. Only under certain simplifying conditions, such as those derived from the Gaussian and house-of-cards approximations, do these general recursions lead to tractable equations for the first few phenotypic moments. The alternative approximations differ in the constraints they impose on the distributions of allelic effects at individual loci. The Gaussian-based prediction that evolution of the phenotypic mean does not change the genetic variance is shown to be a consequence of the assumption that the allelic distributions are never skewed. We present both analytical and numerical results delimiting the parameter values consistent with our approximations.},
author = {Nicholas Barton and Turelli, Michael},
journal = {Genetical Research},
number = {2},
pages = {157 -- 174},
publisher = {Cambridge University Press},
title = {{Adaptive landscapes, genetic distance, and the evolution of quantitative characters}},
doi = {10.1017/S0016672300026951},
volume = {49},
year = {1987},
}