@article{2542, abstract = {A trpE-fusion protein containing a C-terminal sequence of a rat metabotropic glutamate receptor, mGluR5, was used to produce an antibody. On immunoblot, the antibody specifically reacted with mGluR5 expressed in mammalian cells and rat brain. Immunohistochemical analysis revealed intense mGluR5-like immunoreactivity (LI) in the olfactory bulb, anterior olfactory nuclei, olfactory tubercle, cerebral cortex, hippocampus, lateral septum, striatum, nucleus accumbens, inferior colliculus, and spinal trigeminal nuclei. The distribution pattern of mGluR5-LI corresponds very well with that of mGluR5 mRNA. Electron microscope analysis of the striatum revealed dense accumulation of immunoreaction products in dendrites which were often provided with asymmetrical synapses. These results suggest that mGluR5 is predominantly located in postsynaptic elements.}, author = {Shigemoto, Ryuichi and Nomura, Sakashi and Ohishi, Hitoshi and Sugihara, Hidemitsu and Nakanishi, Shigetada and Mizuno, Noboru}, issn = {0304-3940}, journal = {Neuroscience Letters}, number = {1}, pages = {53 -- 57}, publisher = {Elsevier}, title = {{Immunohistochemical localization of a metabotropic glutamate receptor, mGluR5, in the rat brain}}, doi = {10.1016/0304-3940(93)90227-C}, volume = {163}, year = {1993}, } @article{2543, abstract = {Pituitary adenylate cyclase-activating polypeptide (PACAP) is a polypeptide hormone related to vasoactive intestinal polypeptide (VIP). Rat PACAP receptor cDNA was isolated from a brain cDNA library by cross-hybridization with rat VIP receptor cDNA. The recombinant PACAP receptor expressed in COS cells bound PACAP with about 1000 times higher affinity than VIP, and PACAP stimulated adenylate cyclase through the cloned PACAP receptor. The rat PACAP receptor consists of 495 amino acids, contains seven transmembrane segments, and has a significant similarity with other Gs-coupled receptors, such as VIP, glucagon, and secretin receptors. PACAP receptor mRNA was abundantly expressed in the brain, but not in the peripheral tissues except for the adrenal gland. In situ hybridization revealed a high level of expression of PACAP receptor mRNA in the hippocampal dentate gyrus, olfactory bulb, and cerebellar cortex.}, author = {Hashimoto, Hitoshi and Ishihara, Takeshi and Shigemoto, Ryuichi and Mori, Kensaku and Nagata, Shigekazu}, issn = {0896-6273}, journal = {Neuron}, number = {2}, pages = {333 -- 342}, publisher = {Elsevier}, title = {{ Molecular cloning and tissue distribution of a receptor for pituitary adenylate cyclase-activating polypeptide}}, doi = {10.1016/0896-6273(93)90188-W}, volume = {11}, year = {1993}, } @article{2544, abstract = {VARIOUS functions of glutamate transmission are mediated by both ionotropic and metabotropic glutamate receptors1. The metabotropic glutamate receptors (mGluRs) consist of at least six different subtypes that are classified into three subgroups, mGluR1/mGluR5, mGluR2/mGluR3, and mGluR4/mGluR6 (refs 1-5), but their physiological roles are largely unknown. Here we report the identification of a very potent agonist for mGluR2/mGluR3, DCG-IV, and the specific localization of mGluR2 in granule cell dendrites that form dendrodendritic synapses with mitral cells in the accessory olfactory bulb. Using the DCG-IV agonist for mGluR2 in combination with slice patchrecording, we demonstrate that the granule cell mGluR2 presynaptically suppresses inhibitory GABA (γ-aminobutyrate) transmission to the mitral cell. Our results indicate that mGluR2 in granule cells plays an important role in the persistent excitation of olfactory sensory transmission in the accessory olfactory bulb by relieving mitral cells from the GABA inhibition.}, author = {Hayashi, Yasunori and Momiyama, Akiko and Takahashi, Tomoyuki and Ohishi, Hitoshi and Ogawa Meguro, Reiko and Shigemoto, Ryuichi and Mizuno, Noboru and Nakanishi, Shigetada}, issn = {0028-0836}, journal = {Nature}, number = {6456}, pages = {687 -- 690}, publisher = {Nature Publishing Group}, title = {{Role of a metabotropic glutamate receptor in synaptic modulation in the accessory olfactory bulb}}, doi = {10.1038/366687a0}, volume = {366}, year = {1993}, } @article{2546, abstract = {Immunochemical characteristics of neostriatal neurons producing substance P receptor (SPR) were examined in adult rats by double- and triple-immunofluorescence methods. In the neostriatum, SPR immunoreactivity was detected in large and medium-sized aspiny neurons. Virtually all SPR-immunoreactive neurons in the neostriatum contained somatostatin (SS) or choline acetyltransferase (ChAT), but not parvalbumin. All SS- and ChAT-immunoreactive neurons in the neostriatum showed SPR immunoreactivity. The co-existence of SS and ChAT was, however, not found in single neurons expressing SPR immunoreactivity. The present results indicate that neostriatal neurons immunoreactive for SPR are segregated into 2 groups: (1) medium-sized, aspiny somatostatinergic, and (2) large, aspiny cholinergic neurons.}, author = {Kaneko, Takeshi and Shigemoto, Ryuichi and Nakanishi, Shigetada and Mizuno, Noboru}, issn = {0006-8993}, journal = {Brain Research}, number = {2}, pages = {297 -- 303}, publisher = {Elsevier}, title = {{Substance P receptor-immunoreactive neurons in the rat neostriatum are segregated into somatostatinergic and cholinergic aspiny neurons}}, doi = {10.1016/0006-8993(93)91548-7}, volume = {631}, year = {1993}, } @article{2723, abstract = {The ground-state density of the Pauli operator in the case of a nonconstant magnetic field with constant direction is studied. It is shown that in the large field limit, the naturally rescaled ground-state density function is bounded from above by the megnetic field, and under some additional conditions, the limit density function is equal to the magnetic field. A restatement of this result yields an estimate on the density of complex orthogonal polynomials with respect to a fairly general weight function. We also prove a special case of the paramagnetic inequality. }, author = {Erdös, László}, issn = {0377-9017}, journal = {Letters in Mathematical Physics}, number = {3}, pages = {219 -- 240}, publisher = {Springer}, title = {{Ground-state density of the Pauli operator in the large field limit}}, doi = {10.1007/BF00761110}, volume = {29}, year = {1993}, } @article{1945, abstract = {The effects of ultra-low (10(-18)-10(-14) M) doses (ULD) of biologically active substances have been reviewed in terms of common regularities of ULD effects and peculiarities of action of various groups of compounds. The most common and at the same time paradoxical regularities of ULD action are bi- or polymodal patterns of dose dependence, absence or presence of an inverse effect at higher doses, and instability of ULD effect. Possible mechanisms of ULD action including the mechanism based on the adaptation theory are discussed.}, author = {Sazanov, Leonid A and Zaǐtsev, Sergei}, issn = {0006-2979}, journal = {Biochemistry (Moscow)}, number = {10}, pages = {1443 -- 1460}, publisher = {Izdatel'stvo Nauka}, title = {{Effect of superlow doses (10(-18)-10-(-14) M) of biologically active substances: general rules, features, and possible mechanisms}}, volume = {57}, year = {1992}, } @article{3469, abstract = {Glutamate-operated ion channels (GluR channels) of the L-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-kainate subtype are found in both neurons and glial cells of the central nervous system. These channels are assembled from the GluR-A, -B, -C, and -D subunits; channels containing a GluR-B subunit show an outwardly rectifying current-voltage relation and low calcium permeability, whereas channels lacking the GluR-B subunit are characterized by a doubly rectifying current-voltage relation and high calcium permeability. Most cell types in the central nervous system coexpress several subunits, including GluR-B. However, Bergmann glia in rat cerebellum do not express GluR-B subunit genes. In a subset of cultured cerebellar glial cells, likely derived from Bergmann glial cells. GluR channels exhibit doubly rectifying current-voltage relations and high calcium permeability, whereas GluR channels of cerebellar neurons have low calcium permeability. Thus, differential expression of the GluR-B subunit gene in neurons and glia is one mechanism by which functional properties of native GluR channels are regulated.}, author = {Burnashev, Nail and Khodorova, Alla and Jonas, Peter M and Helm, P. and Wisden, William and Monyer, Hannah and Seeburg, Peter and Sakmann, Bert}, issn = {0036-8075}, journal = {Science}, number = {5063}, pages = {1566 -- 1570}, publisher = {American Association for the Advancement of Science}, title = {{Calcium-permeable AMPA-kainate receptors in fusiform cerebellar glial cells.}}, doi = {10.1126/science.1317970}, volume = {256}, year = {1992}, } @article{3470, abstract = {Currents activated by glutamate receptor (GluR) agonists were recorded from outside-out patches isolated from the soma of visually identified pyramidal neurones of the (CA3 and CA1 region of rat hippocampal slices. α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). L-glutamate (L-Glu), and kainate (KA) were delivered either by bath application through perfusion of the recording chamber or by rapid application via a piezo-driven two-barrelled fast application system. 2. Bath application of each of the three agonists activated inward currents in all patches (n = 134) at holding potentials of -50 or -60 mV. The current amplitude increased in size between 3 to 30 μM-AMPA and 100 μM to 1 mM-KA. With this slow mode of bath application, the responses showed no apparent desensitization even at saturating concentrations of AMPA (30 μM) and KA (1 mM). 3. The ratio of currents activated by 30 μM-AMPA and 300 μM-KA showed a characteristic difference between CA3 and CA1 neurones. The ratio was 0.242 ± 0.028 (mean ± S.E.M., n = 16) for CA3 cell patches and 0.097 ± 0.012 (n = 8) for CA1 cell patches indicating that GluRs in the two cell populations are different. 4. The steady-state current-voltage relations (I-Vs) for AMPA- and KA-activated currents showed pronounced outward rectification for both cell types (when the main cations are Na+ in the bath and Cs+ in the pipette solution). The current reversed close to 0 mV and the ratio of chord conductances 80 mV on either side of the reversal potential was 2.66 for KA-activated currents in CA3 cell patches and 2.60 in CA1 cell patches. AMPA-activated currents showed a time-dependent increase after steps to positive membrane potentials and a decrease after steps to negative voltages, indicating that a gating process is responsible for outward rectification of the steady-state I-IV. 5. The permeability (P) of GluR channels was high for Na+ as compared to Cs+ for both cell types (P(Na)/P(Cs) = 0.88 and 0.84). The permeability was low for N-methyl-D-glucamine+ (P(NMG)/P(Cs) ≤ 0.03) and Ca2+ (P(Ca)/P(Cs) ≤0.05). 6. The current noise level increased during application of AMPA or KA. Apparent single-channel conductances obtained from fluctuation analysis were higher for AMPA than for KA, but similar for both cell types. In CA3 cell patches, AMPA activated channels with an apparent chord conductance of 7.2 pS, KA of 3.0 pS conductance. 7. Fast agonist application revealed desensitization of GluR channels which was dependent on the type of agonist, currents activated by AMPA and L-Glu rose rapidly to a peak and then desensitized to a steady-state current. In contrast, currents activated by fast application of KA rose to a plateau and did not desensitize. The steady state current expressed as a percentage of the peak current was higher for L-Glu than for AMPA and slightly higher for CA3 than for CA1 cell patches. For CA3 cell patches, this fraction amounted to 6.2 %, with 300 μM-L-Glu and 2.8%, with 300 μM-AMPA. For CA1 cell patches, corresponding values were 3.6 and 1.9 % 8. The dose response relations for the peak current activated by AMPA and L-Glu and the steady-state current activated by KA were similar for CA3 and CA1 cell patches. The order of potency was AMPA > L-Glu ≃ KA for both cell types EC50 values 189, 342 and 344 μM for CA3 cell patches and 183, 424 and 474 μM for CA1 cell patches). In all cases, the Hill coefficients ranged between 12 and 1.7. 8. The rise of AMPA and L-Glu-activated currents became faster with increasing agonist concentration for both cell types. With L-Glu, rise times decreased from about 3 ms at 100 μM to 500 μs at 3 mM. The delay for agonist concentrations ≥ 300 μM was described by the sum of two exponential functions. The time constant of the predominant fast component was slightly concentration dependent and decreased from about 12 ms at 300 μM to 8 ms at 3 mM-L-Glu. 10. The current voltage relations of the peak currents activated by 300 μM-AMPA were linear for both cell types with a reversal potential close to OmV. 11. It is concluded that the GluR channels in pyramidal cells of hippocampal CA3 and CA1 regions are distinet but share many pharmacological and functional properties. Comparison of the properties of native and recombinant GluRs suggests that in both CA3 and CA1 regions GluR channels are hetero-oligomers containing the GluR-B subunit.}, author = {Jonas, Peter M and Sakmann, Bert}, issn = {0022-3751}, journal = {Journal of Physiology}, pages = {143 -- 171}, publisher = {Wiley-Blackwell}, title = {{Glutamate receptor channels in isolated patches from CA1 and CA3 pyramidal cells of rat hippocampal slices}}, doi = {10.1113/jphysiol.1992.sp019294 }, volume = {455}, year = {1992}, } @article{3471, abstract = {1. Outside-out patches were isolated from granule cells of dentate gyrus and pyramidal cells of CA3 and CA1 regions of rat hippocampal slices. Patches were exposed briefly to L-glutamate using a piezo-driven double-barrelled application pipette. 2. Applications of glutamate (1 mM) of 1 ms duration activated patch currents which rose and decayed rapidly. The 20-80% rise time of these glutamate receptor (GluR)-mediated currents was usually 0.2-0.6 ms. At -50 mV the peak current varied from 10 to 500 pA in different patches. 3. The peak current-voltage relation for brief pulses of 1 mM glutamate was virtually linear in normal extracellular solution for patches from the three cell types (-100 to 60 mV). 4. The permeability of GluR channels activated at the peak to Ca2+, relative to K+, was less than 0.1 for all three cell types (under bi-ionic conditions with Ca2+ on the extracellular side and K+ on the intracellular side of the membrane). 5. The offset decay time constant of the current following 1 ms pulses of 1 mM glutamate was brief, with mean values of 3.0 +/- 0.8, 2.5 +/- 0.7, and 2.3 +/- 0.7 ms for dentate, CA3 and CA1 cell patches, respectively. Offset time constants were independent of membrane potential and independent of glutamate concentration (200 microM and 1 mM) for the three cell types. 6. Applications of 1 mM glutamate of 100 ms duration showed that glutamate responses desensitized rapidly. The time constants for desensitization were 9.4 +/- 2.7, 11.3 +/- 2.8, and 9.3 +/- 2.8 ms for patches from dentate, CA3 and CA1 cells respectively. Desensitization time constants were only weakly dependent on glutamate concentration (200 microM and 1 mM) for the three cell types. Thus offset time constants are about four times faster than desensitization time constants for both glutamate concentrations. 7. Double pulse application of glutamate indicated that even a 1 ms pulse of 1 mM glutamate causes partial (about 60%) desensitization of GluR channels. The time course of recovery from desensitization was slower in dentate gyrus granule cell patches than in CA3 or CA1 pyramidal cell patches. 8. Desensitization was studied at equilibrium by exposing patches to low glutamate concentrations for at least 15 s before a 1 ms test pulse of 1 mM glutamate.}, author = {Colquhoun, D. and Jonas, Peter M and Sakmann, Bert}, issn = {0022-3751}, journal = {Journal of Physiology}, pages = {261 -- 287}, publisher = {Wiley-Blackwell}, title = {{Action of brief pulses of glutamate on AMPA/kainate receptors in patches from different neurones of rat hippocampal slices}}, doi = {10.1113/jphysiol.1992.sp019417}, volume = {458}, year = {1992}, } @article{3472, abstract = {A novel potassium-selective channel which is active at membrane potentials between -100 mV and +40 mV has been identified in peripheral myelinated axons of Xenopus laevis using the patch-clamp technique. At negative potentials with 105 mM-K on both sides of the membrane, the channel at 1 kHz resolution showed a series of brief openings and closings interrupted by longer closings, resulting in a flickery bursting activity. Measurements with resolution up to 10 kHz revealed a single-channel conductance of 49 pS with 105 mM-K and 17 pS with 2.5 mM-K on the outer side of the membrane. The channel was selective for K ions over Na ions (PNa/PK = 0.033). The probability of being within a burst in outside-out patches varied from patch to patch (> 0.2, but often > 0.9), and was independent of membrane potential. Open-time histograms were satisfactorily described with a single exponential (tau o = 0.09 msec), closed times with the sum of three exponentials (tau c = 0.13, 5.9, and 36.6 msec). Sensitivity to external tetraethylammonium was comparatively low (IC50 = 19.0 mM). External Cs ions reduced the apparent unitary conductance for inward currents at Em = -90 mV (IC50 = 1.1 mM). Ba and, more potently, Zn ions lowered not only the apparent single-channel conductance but also open probability. The local anesthetic bupivacaine with high potency reduced probability of being within a burst (IC50 = 165 nM). The flickering K channel is clearly different from the other five types of K channels identified so far in the same preparation. We suggest that this channel may form the molecular basis of the resting potential in vertebrate myelinated axons.}, author = {Koh, Duk and Jonas, Peter M and Bräu, Michael and Vogel, Werner}, issn = {0022-2631}, journal = {Journal of Membrane Biology}, pages = {149 -- 162}, publisher = {Springer}, title = {{A TEA-insensitive flickering potassium channel active around the resting potential in myelinated nerve}}, doi = {10.1007/BF00231893}, volume = {130}, year = {1992}, } @article{3581, abstract = {A number of rendering algorithms in computer graphics sort three-dimensional objects by depth and assume that there is no cycle that makes the sorting impossible. One way to resolve the problem caused by cycles is to cut the objects into smaller pieces. In this paper we address the problem of estimating how many such cuts arc always sufficient. We also consider a few related algorithmic and combinatorial geometry problems. For example, we demonstrate that n lines in space can be sorted in randomized expected time O(n4’st’), provided that they define no cycle. We also prove an 0(n7’4) upper bound on the number of points in space so that there are n lines with the property that for each point there are at least three noncoplanar lines that contain it. }, author = {Chazelle, Bernard and Edelsbrunner, Herbert and Guibas, Leonidas and Pollack, Richard and Seidel, Raimund and Sharir, Micha and Snoeyink, Jack}, issn = {0925-7721}, journal = {Computational Geometry: Theory and Applications}, number = {6}, pages = {305 -- 323}, publisher = {Elsevier}, title = {{Counting and cutting cycles of lines and rods in space}}, doi = {10.1016/0925-7721(92)90009-H}, volume = {1}, year = {1992}, } @article{3645, abstract = {Three components of mating call (pulse duration, cycle length, and fundamental frequency) were measured and six diagnostic enzyme loci scored across the hybrid zone between the toads Bombina bombina and B. variegata. All three call components differ significantly, but only cycle length is diagnostic. The clines in call coincide with those for enzymes, and have similar widths. This suggests that there is no strong selection on any of these characters. There are significant correlations between electrophoretic markers and call components, but these are no stronger than would be expected if the electrophoretic loci and the genes causing mating call were neutral. The selection differential on the call is no greater than 6% of the difference in mean cycle length between the two taxa. There is a substantial increase in the variance of cycle length in the center of the zone, suggesting that a small number of loci are involved (≈ three). Recombination between these loci will hinder the evolution of reinforcement and may partly be responsible for the lack of premating isolation between B. bombina and B. variegata.}, author = {Sanderson, Neil and Szymura, Jacek and Barton, Nicholas H}, issn = {0014-3820}, journal = {Evolution}, number = {3}, pages = {595 -- 607}, publisher = {Wiley-Blackwell}, title = {{Variation in mating call across the hybrid zone between the fire-bellied toads Bombina bombina and B. variegata}}, doi = {10.1111/j.1558-5646.1992.tb02068.x}, volume = {46}, year = {1992}, } @article{4043, abstract = {It is shown that a triangulation of a set of n points in the plane that minimizes the maximum angle can be computed in time O(n2 log n) and space O(n). The algorithm is fairly easy to implement and is based on the edge-insertion scheme that iteratively improves an arbitrary initial triangulation. It can be extended to the case where edges are prescribed, and, within the same time- and space-bounds, it can lexicographically minimize the sorted angle vector if the point set is in general position. Experimental results on the efficiency of the algorithm and the quality of the triangulations obtained are included.}, author = {Edelsbrunner, Herbert and Tan, Tiow and Waupotitsch, Roman}, issn = {1095-7111}, journal = {SIAM Journal on Scientific Computing}, number = {4}, pages = {994 -- 1008}, publisher = {Society for Industrial and Applied Mathematics }, title = {{An O(n^2 log n) time algorithm for the MinMax angle triangulation}}, doi = {10.1137/0913058}, volume = {13}, year = {1992}, } @article{4046, abstract = {The main contribution of this work is an O(n log n + k)-time algorithm for computing all k intersections among n line segments in the plane. This time complexity is easily shown to be optimal. Within the same asymptotic cost, our algorithm can also construct the subdivision of the plane defined by the segments and compute which segment (if any) lies right above (or below) each intersection and each endpoint. The algorithm has been implemented and performs very well. The storage requirement is on the order of n + k in the worst case, but it is considerably lower in practice. To analyze the complexity of the algorithm, an amortization argument based on a new combinatorial theorem on line arrangements is used.}, author = {Chazelle, Bernard and Edelsbrunner, Herbert}, issn = {1557-735X}, journal = {Journal of the ACM}, number = {1}, pages = {1 -- 54}, publisher = {ACM}, title = {{An optimal algorithm for intersecting line segments in the plane}}, doi = {10.1145/147508.147511}, volume = {39}, year = {1992}, } @article{4047, abstract = {Arrangements of curves in the plane are fundamental to many problems in 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 Edelsbrunner (1986) and Chazelle (1985) 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 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}, issn = {0304-3975}, journal = {Theoretical Computer Science}, number = {2}, pages = {319 -- 336}, publisher = {Elsevier}, title = {{Arrangements of curves in the plane - topology, combinatorics, and algorithms}}, doi = {10.1016/0304-3975(92)90319-B}, volume = {92}, year = {1992}, } @article{4048, abstract = {Given a sequence of n points that form the vertices of a simple polygon, we show that determining a closest pair requires OMEGA(n log n) time in the algebraic decision tree model. Together with the well-known O(n log n) upper bound for finding a closest pair, this settles an open problem of Lee and Preparata. We also extend this O(n log n) upper bound to the following problem: Given a collection of sets with a total of n points in the plane, find for each point a closest neighbor that does not belong to the same set.}, author = {Aggarwal, Alok and Edelsbrunner, Herbert and Raghavan, Prabhakar and Tiwari, Prasoon}, issn = {1872-6119}, journal = {Information Processing Letters}, number = {1}, pages = {55 -- 60}, publisher = {Elsevier}, title = {{Optimal time bounds for some proximity problems in the plane}}, doi = {10.1016/0020-0190(92)90133-G}, volume = {42}, year = {1992}, } @inproceedings{4049, abstract = {The edge-insertion paradigm improves a triangulation of a finite point set in R2 iteratively by adding a new edge, deleting intersecting old edges, and retriangulating the resulting two polygonal regions. After presenting an abstract view of the paradigm, this paper shows that it can be used to obtain polynomial time algorithms for several types of optimal triangulations.}, author = {Bern, Marshall and Edelsbrunner, Herbert and Eppstein, David and Mitchell, Stephen and Tan, Tiow}, booktitle = {1st Latin American Symposium on Theoretical Informatics}, editor = {Simon, Imre}, isbn = {978-3-540-55284-0}, location = {São Paulo, Brazil}, pages = {46 -- 60}, publisher = {Springer}, title = {{Edge insertion for optimal triangulations}}, doi = {10.1007/BFb0023816}, volume = {583}, year = {1992}, } @article{4050, author = {Edelsbrunner, Herbert}, journal = {Discrete & Computational Geometry}, number = {1}, pages = {217 -- 217}, publisher = {Springer}, title = {{Guest editor's foreword}}, doi = {10.1007/BF02293046}, volume = {8}, year = {1992}, } @article{4053, abstract = {We show that the maximum number of edges bounding m faces in an arrangement of n line segments in the plane is O(m2/3n2/3+nα(n)+nlog m). This improves a previous upper bound of Edelsbrunner et al. [5] and almost matches the best known lower bound which is Ω(m2/3n2/3+nα(n)). In addition, we show that the number of edges bounding any m faces in an arrangement of n line segments with a total of t intersecting pairs is O(m2/3t1/3+nα(t/n)+nmin{log m,log t/n}), almost matching the lower bound of Ω(m2/3t1/3+nα(t/n)) demonstrated in this paper.}, author = {Aronov, Boris and Edelsbrunner, Herbert and Guibas, Leonidas and Sharir, Micha}, issn = {0209-9683}, journal = {Combinatorica}, number = {3}, pages = {261 -- 274}, publisher = {Springer}, title = {{The number of edges of many faces in a line segment arrangement}}, doi = {10.1007/BF01285815}, volume = {12}, year = {1992}, } @article{4195, abstract = {The effects of tri-iodothyronine (T3), which are known to affect cerebellar development, were tested on neuronal survival and differentiation of cultured cerebellar granule neurons. T3 in physiological concentrations increased both granule neuron survival after three days in culture and synaptic vesicle protein formation, as shown by immunostaining with antibodies against synaptophysin. Likewise, T3 increased the mRNA level for synapsin(I), but not that for GAP43 in granule neurons. Antibodies against microtubule associated protein Tau, which is expressed in developing neurites, showed that T3 also enhanced neurite formation.}, author = {Heisenberg, Carl-Philipp J and Thoenen, Hans and Lindholm, Dan}, issn = {1473-558X}, journal = {Neuroreport}, number = {8}, pages = {685 -- 688}, publisher = {Lippincott, Williams & Wilkins}, title = {{Triiodothyronine Regulates Survival and Differentiation of Rat Cerebellar Granule Neurons}}, doi = {10.1097/00001756-199208000-00008 }, volume = {3}, year = {1992}, }