@inproceedings{4087, abstract = {This paper offers combinatorial results on extremum problems concerning the number of tetrahedra in a tetrahedrization of n points in general position in three dimensions, i.e. such that no four points are coplanar. It also presents an algorithm that in O(nlog n) time constructs a tetrahedrization of a set of n points consisting of at most 3n–11 tetrahedra.}, author = {Edelsbrunner, Herbert and Preparata, Franco and West, Douglas}, booktitle = { International Symposium on Symbolic and Algebraic Computation}, location = {Rome, Italy}, pages = {315 -- 331}, publisher = {Springer}, title = {{Tetrahedrizing point sets in three dimensions}}, doi = {10.1007/3-540-51084-2_31}, volume = {358}, year = {1989}, } @article{4088, abstract = {Anarrangement ofn lines (or line segments) in the plane is the partition of the plane defined by these objects. Such an arrangement consists ofO(n 2) regions, calledfaces. In this paper we study the problem of calculating and storing arrangementsimplicitly, using subquadratic space and preprocessing, so that, given any query pointp, we can calculate efficiently the face containingp. First, we consider the case of lines and show that with (n) space1 and (n 3/2) preprocessing time, we can answer face queries in (n)+O(K) time, whereK is the output size. (The query time is achieved with high probability.) In the process, we solve three interesting subproblems: (1) given a set ofn points, find a straight-edge spanning tree of these points such that any line intersects only a few edges of the tree, (2) given a simple polygonal path , form a data structure from which we can find the convex hull of any subpath of quickly, and (3) given a set of points, organize them so that the convex hull of their subset lying above a query line can be found quickly. Second, using random sampling, we give a tradeoff between increasing space and decreasing query time. Third, we extend our structure to report faces in an arrangement of line segments in (n 1/3)+O(K) time, given(n 4/3) space and (n 5/3) preprocessing time. Lastly, we note that our techniques allow us to computem faces in an arrangement ofn lines in time (m 2/3 n 2/3+n), which is nearly optimal.}, author = {Edelsbrunner, Herbert and Guibas, Leonidas and Hershberger, John and Seidel, Raimund and Sharir, Micha and Snoeyink, Jack and Welzl, Emo}, issn = {1432-0444}, journal = {Discrete & Computational Geometry}, number = {1}, pages = {433 -- 466}, publisher = {Springer}, title = {{Implicitly representing arrangements of lines or segments}}, doi = {10.1007/BF02187742}, volume = {4}, year = {1989}, } @article{4089, abstract = {Motivated by a number of motion-planning questions, we investigate in this paper some general topological and combinatorial properties of the boundary of the union ofn regions bounded by Jordan curves in the plane. We show that, under some fairly weak conditions, a simply connected surface can be constructed that exactly covers this union and whose boundary has combinatorial complexity that is nearly linear, even though the covered region can have quadratic complexity. In the case where our regions are delimited by Jordan acrs in the upper halfplane starting and ending on thex-axis such that any pair of arcs intersect in at most three points, we prove that the total number of subarcs that appear on the boundary of the union is only (n(n)), where(n) is the extremely slowly growing functional inverse of Ackermann's function.}, author = {Edelsbrunner, Herbert and Guibas, Leonidas and Hershberger, John and Pach, János and Pollack, Richard and Seidel, Raimund and Sharir, Micha and Snoeyink, Jack}, issn = {1432-0444}, journal = {Discrete & Computational Geometry}, number = {1}, pages = {523 -- 539}, publisher = {Springer}, title = {{On arrangements of Jordan arcs with three intersections per pair}}, doi = {10.1007/BF02187745}, volume = {4}, year = {1989}, } @inproceedings{4092, author = {Chazelle, Bernard and Edelsbrunner, Herbert and Guibas, Leonidas and Sharir, Micha}, booktitle = {16th International Colloquium on Automata, Languages, and Programming}, location = {Stresa, Italy}, pages = {179 -- 193}, publisher = {Springer}, title = {{A singly exponential stratification scheme for real semi-algebraic varieties and its applications}}, doi = {10.1007/BFb0035760}, volume = {372}, year = {1989}, } @article{4093, abstract = {This paper investigates the combinatorial and computational aspects of certain extremal geometric problems in two and three dimensions. Specifically, we examine the problem of intersecting a convex subdivision with a line in order to maximize the number of intersections. A similar problem is to maximize the number of intersected facets in a cross-section of a three-dimensional convex polytope. Related problems concern maximum chains in certain families of posets defined over the regions of a convex subdivision. In most cases we are able to prove sharp bounds on the asymptotic behavior of the corresponding extremal functions. We also describe polynomial algorithms for all the problems discussed.}, author = {Chazelle, Bernard and Edelsbrunner, Herbert and Guibas, Leonidas}, issn = {1432-0444}, journal = {Discrete & Computational Geometry}, number = {1}, pages = {139 -- 181}, publisher = {Springer}, title = {{The complexity of cutting complexes}}, doi = {10.1007/BF02187720}, volume = {4}, year = {1989}, } @article{4309, abstract = {Three methods for estimating the average level of gene flow in natural population are discussed and compared. The three methods are FST, rare alleles, and maximum likelihood. All three methods yield estimates of the combination of parameters (the number of migrants [Nm] in a demic model or the neighborhood size [4πDσ2] in a continuum model) that determines the relative importance of gene flow and genetic drift. We review the theory underlying these methods and derive new analytic results for the expectation of FST in stepping-stone and continuum models when small sets of samples are taken. We also compare the effectiveness of the different methods using a variety of simulated data. We found that the FST and rare-alleles methods yield comparable estimates under a wide variety of conditions when the population being sampled is demographically stable. They are roughly equally sensitive to selection and to variation in population structure, and they approach their equilibrium values at approximately the same rate. We found that two different maximum-likelihood methods tend to yield biased estimates when relatively small numbers of locations are sampled but more accurate estimates when larger numbers are sampled. Our conclusion is that, although FST and rare-alleles methods are expected to be equally effective in analyzing ideal data, practical problems in estimating the frequencies of rare alleles in electrophoretic studies suggest that FST is likely to be more useful under realistic conditions.}, author = {Slatkin, Montgomery and Barton, Nicholas H}, issn = {1558-5646}, journal = {Evolution; International Journal of Organic Evolution}, number = {7}, pages = {1349 -- 1368}, publisher = {Wiley-Blackwell}, title = {{A comparison of three methods for estimating average levels of gene flow}}, doi = {10.1111/j.1558-5646.1989.tb02587.x }, volume = {43}, year = {1989}, } @article{4312, author = {Barton, Nicholas H and Turelli, Michael}, issn = {1545-2948}, journal = {Annual Review of Genetics}, pages = {337 -- 370}, publisher = {Annual Reviews}, title = {{Evolutionary quantitative genetics: how little do we know?}}, doi = {10.1146/annurev.ge.23.120189.002005}, volume = {23}, year = {1989}, } @inbook{4313, author = {Barton, Nicholas H}, booktitle = {Speciation and its consequences}, editor = {Otte, Daniel and Endler, John}, isbn = {‎ 978-0878936571}, publisher = {Sinauer Press}, title = {{Founder effect speciation}}, year = {1989}, } @article{4314, abstract = {Polygenic variation can be maintained by a balance between mutation and stabilizing selection. When the alleles responsible for variation are rare, many classes of equilibria may be stable. The rate at which drift causes shifts between equilibria is investigated by integrating the gene frequency distribution W2N II (pq)4N mu-1. This integral can be found exactly, by numerical integration, or can be approximated by assuming that the full distribution of allele frequencies is approximately Gaussian. These methods are checked against simulations. Over a wide range of population sizes, drift will keep the population near an equilibrium which minimizes the genetic variance and the deviation from the selective optimum. Shifts between equilibria in this class occur at an appreciable rate if the product of population size and selection on each locus is small (Ns alpha 2 less than 10). The Gaussian approximation is accurate even when the underlying distribution is strongly skewed. Reproductive isolation evolves as populations shift to new combinations of alleles: however, this process is slow, approaching the neutral rate (approximately mu) in small populations.}, author = {Barton, Nicholas H}, issn = {1469-5073}, journal = {Genetical Research}, number = {1}, pages = {59 -- 78}, publisher = {Cambridge University Press}, title = {{The divergence of a polygenic system under stabilising selection, mutation and drift}}, doi = {10.1017/S0016672300028378}, volume = {54}, year = {1989}, } @inproceedings{4596, abstract = {A real-time temporal logic for the specification of reactive systems is introduced. The novel feature of the logic, TPTL, is the adoption of temporal operators as quantifiers over time variables; every modality binds a variable to the time(s) it refers to. TPTL is demonstrated to be both a natural specification language and a suitable formalism for verification and synthesis. A tableau-based decision procedure and model-checking algorithm for TPTL are presented. Several generalizations of TPTL are shown to be highly undecidable.}, author = {Alur, Rajeev and Henzinger, Thomas A}, booktitle = {30th Annual Symposium on Foundations of Computer Science}, isbn = {0-8186-1982-1}, issn = {1558-0814}, location = {Research Triangle Park, NC, USA}, pages = {164 -- 169}, publisher = {IEEE}, title = {{A really temporal logic}}, doi = {10.1109/SFCS.1989.63473}, year = {1989}, } @article{2479, abstract = {Distribution of putative glutamatergic neurons in the lower brainstem and cerebellum of the rat was examined immunocytochemically by using a monoclonal antibody against phosphate-activated glutaminase, which has been proposed to be a major synthetic enzyme of transmitter glutamate and so may serve as a marker for glutamatergic neurons in the central nervous system. Intensely-immunolabeled neuronal cell bodies were densely distributed in the main precerebellar nuclei sending mossy fibers to the cerebellum; in the pontine nuclei, pontine tegmental reticular nucleus of Bechterew, external cuneate nucleus, and lateral reticular nucleus of the medulla oblongata. Phosphate-activated glutaminase-immunoreactive granular deposits were densely seen in the brachium pontis and restiform body, suggesting the immunolabeling of mossy fibers of passage. In the cerebellum, neuropil within the granule cell layer of the cerebellar cortex displayed intense phosphate-activated glutaminase-immunoreactivity, and that within the deep cerebellar nuclei showed moderate immunoreactivity. These results indicate that many mossy fiber terminals originate from phosphate-activated glutaminase-containing neurons and utilize phosphate-activated glutaminase for the synthesis of transmitter glutamate. Intensely-immunostained neuronal cell bodies were further observed in other regions which have been reported to contain neurons sending mossy fibers to the cerebellum; in the dorsal part of the principal sensory trigeminal nucleus, dorsomedial part of the oral subnucleus of the spinal trigeminal nucleus, interpolar subnucleus of the spinal trigeminal nucleus, paratrigeminal nucleus, supragenual nucleus, regions dorsal to the abducens nucleus and genu of the facial nerve, superior and medial vestibular nuclei, cell groups f, x and y, hypoglossal prepositus nucleus, intercalated nucleus, nucleus of Roller, reticular regions intercalated between the motor trigeminal and principal sensory trigeminal nuclei, linear nucleus, and gigantocellular and paramedian reticular formation. Neuronal cell bodies with intense phosphate-activated glutaminase-immunoreactivity were also found in other brainstem regions, such as the paracochlear glial substance, posterior ventral cochlear nucleus, and cell group e. Although it is still controversial whether all glutamatergic neurons use phosphate-activated glutaminase in a transmitter-related process and whether phosphate-activated glutaminase is involved in other metabolism-related processes, the neurons showing intense phosphate-activated glutaminase-immuno-reactivity in the present study were suggested to be putative glutamatergic neurons.}, author = {Kaneko, Takeshi and Itoh, Kazuo and Shigemoto, Ryuichi and Mizuno, Noboru}, issn = {1873-7544}, journal = {Neuroscience}, number = {1}, pages = {79 -- 98}, publisher = {Elsevier}, title = {{Glutaminase-like immunoreactivity in the lower brainstem and cerebellum of the adult rat}}, doi = {10.1016/0306-4522(89)90109-7}, volume = {32}, year = {1989}, } @article{2525, abstract = {This paper describes the amino acid sequence of the rat substance P receptor and its comparison with that of the rat substance K receptor on the basis of molecular cloning and sequence analysis. From a rat brain cDNA library constructed with an RNA expression vector, we identified a cDNA mixture containing a functional substance P receptor cDNA by examining electrophysiologically a receptor expression following injection of the mRNAs synthesized in vitro into Xenopus oocytes. A receptor cDNA clone was then isolated by cross-hybridization with the bovine substance K receptor DNA. The clone was confirmed by selective binding of substance P to the cloned receptor expressed in mammalian COS cells. The deduced amino acid sequence (407 amino acid residues) possesses seven putative membrane spanning domains and shows a sequence similarity to the members of G-protein-coupled receptors. The rat substance P and substance K receptor are very similar in both size and amino acid sequences, particularly in the putative transmembrane similarity is in marked contrast to the sequence divergence in the amino- and carboxyl-terminal regions and the third cytoplasmic loop. The observed sequence similarytity and divergence would thus contribute to the expression of similar but pharmacological regions and the first and second cytoplasmic loops. This distinguishable activities of the two tachykinin receptors.}, author = {Yokota, Yoshifumi and Sasai, Yoshiki and Tanaka, Kohichi and Fujiwara, Tsutomu and Tsuchida, Kunihiro and Shigemoto, Ryuichi and Kakizuka, Akira and Ohkubo, Hiroaki and Nakanishi, Shigetada}, issn = {1083-351X}, journal = {Journal of Biological Chemistry}, number = {30}, pages = {17649 -- 17652}, publisher = {American Society for Biochemistry and Molecular Biology}, title = {{Molecular characterization of a functional cDNA for rat substance P receptor}}, doi = {doi.org/10.1016/S0021-9258(19)84619-7}, volume = {264}, year = {1989}, } @article{2526, abstract = {When WGA-HRP (wheat germ agglutinin-horseradish peroxidase conjugate) or HRP was injected into the regions around the superior central and/or the dorsal raphe nuclei in the cat, cell bodies of a number of non-pyramidal neurons were labeled in Ammon's horn. Thus the existence of direct projections from non-pyramidal neurons in Ammon's horn to the rostral raphe regions in the brainstem was suggested in the cat.}, author = {Ino, Tadashi and Itoh, Kazuo and Kamiya, Hiroto and Kaneko, Takeshi and Shigemoto, Ryuichi and Akiguchi, Ichiro and Mizuno, Noboru}, issn = {1872-6240}, journal = {Brain Research}, number = {1}, pages = {157 -- 161}, publisher = {Elsevier}, title = {{Direct projections from Ammon's horn to the rostral raphe regions in the brainstem of the cat}}, doi = {10.1016/0006-8993(89)91346-2}, volume = {479}, year = {1989}, } @article{2527, author = {Akimoto, Masumi and Shigemoto, Ryuichi and Kawamura, Makiko and Yamagata, Hideharu and Kurihara, Takeshi and Takata, S and Miwa, Yoko and Akagami, N and Katsu, Kenichi and Yamauchi, D}, journal = {Japanese Journal of Gastroenterology}, number = {11}, pages = {2627}, publisher = {Japanese Society of Gastroenterology}, title = {{Effect of endothelin on gastric mucosal blood flow in rat}}, doi = {10.11405/nisshoshi1964.86.2627}, volume = {86}, year = {1989}, } @article{1941, author = {Sazanov, Leonid A and Karavaev, V A and Kukushkin, A K}, issn = {1990-7923}, journal = {Russian Journal of Physical Chemistry B}, pages = {3351 -- 3354}, publisher = {Elsevier}, title = {{Mathematical model of photosynthesis regulation accounts for the effects of changes in external conditions and observed oscillations}}, volume = {52}, year = {1988}, } @article{3655, abstract = {The structural basis and distribution of variation in the ribosomal RNA multigene family ( rDNA) was studied in the X0 and neo-XY races of the Alpine grasshopper Podisma pedestris. Restriction-enzyme sites in the gene region of the rDNA repeat were identical in both races and homogeneous in the rDNA family. In contrast, sites for Hind111 and PvuII in the intergenic spacer (IGS) region showed racial divergence and variation within the rDNA family and within populations. A short insertion in the 28s gene region was present in a minority of repeats in both races. The distributions of four polymorphic IGS Hind111 fragments were surveyed at 43 locations in and around the hybrid zone. Two of these fragments appear to be distributed as clines, one of which is strongly associated with the neo-X chromosome. The other two fragments show considerable variation in both races and show negative association. It is proposed that the clinally distributed variants arise from processes of amplification and divergence of IGS sequence variants and that such divergence may contribute to hybrid inviability. }, author = {Dallas, John and Barton, Nicholas H and Dover, Gabriel}, issn = {1537-1719}, journal = {Molecular Biology and Evolution}, number = {6}, pages = {660 -- 674}, publisher = {Oxford University Press}, title = {{Interracial rDNA variation in the grasshopper Podisma Pedestris}}, doi = {10.1093/oxfordjournals.molbev.a040528}, 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 = {Edelsbrunner, Herbert and Preparata, Franco}, issn = {0890-5401}, 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 = {Edelsbrunner, Herbert and Skiena, Steven}, issn = {1095-7111}, 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 = {Edelsbrunner, Herbert}, booktitle = {15th International Colloquium on Automata, Languages and Programming}, isbn = {978-3-540-19488-0}, location = {Tampere, Finland}, 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 = {Edelsbrunner, Herbert and Guibas, Leonidas and Pach, János and Pollack, Richard and Seidel, Raimund and Sharir, Micha}, booktitle = {15th International Colloquium on Automata, Languages and Programming}, isbn = {978-3-540-19488-0}, keywords = {line segment, computational geometry, Jordan curve, cell decomposition, vertical tangency}, location = {Tampere, Finland}, 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}, }