| | 2 | Author
| LudwigK. Raut, R. Üdiger, M. Ues | Requires cookie* | | | Title
| The First Biflavone Found in Liverworts and Other Phenolics and Terpenoids from Chandonanthus hirtellus ssp. giganteus and Plagiochila asplenioides  | | | | Abstract
| C handonanthus hirtellus ssp. giganteus, Plagiochila asplenioides, Liverworts, Biflavone, G ym nom itrenol A biflavone was isolated from a liverw ort (C handonanthus hirtellus ssp. giganteus) for the first time. Its stru ctu re was d eterm in ed as dicranolom in. M oreover luteolin and the new com pound vanillic acid-4-O -neohesperidoside were identified from this C handonanthus sp e cies. From Plagiochila asplenioides we isolated the new sesquiterpenoid (-)-gym nom itr-8(12)-en-9/3-ol with chair conform ation of the cyclohexane ring to g eth er with plagiochiline P and the d iterpen o id anadensin, both new to this liverwort. | | | |
Reference
| Z. Naturforsch. 54c, 6 (1999); received July 27/O ctober 6 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0006.pdf | | | | Identifier
| ZNC-1999-54c-0006 | | | | Volume
| 54 | |
| 3 | Author
| Z. | Requires cookie* | | | Title
| Rosmarinic A dd and Other Phenolic Acids in Hairy Roots of Hyssopus officinalis | | | | Abstract
| H yssopus officinalis, A grobacterium rhizogenes, T ransform ed R oots, Phenolic Acids, R osm arinic Acid H airy roots of H yssopus officinalis L. w ere induced by infection of petioles with A grobacte rium rhizogenes LBA 9402 and stu d ied for production of phenolic acids, especially rosm arinic acid (R A). The highest con ten t o f rosm arinic acid (about 6 % of dry w eight) was obtain ed in hairy roots grow n in G a m b o rg 's B5 liquid m edium containing 10% (w/v) sucrose. The level was at least 60% higher th an those found in callus, cell suspension culture and roots of one-year-old field grow n plants. A p a rt from R A , nine o th er phenolic acids w ere d etec ted in transform ed roots and quantified by gas chrom atography. | | | |
Reference
| Z. Naturforsch. 54c, 11 (1999); received July 15/Septem ber 9 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0011.pdf | | | | Identifier
| ZNC-1999-54c-0011 | | | | Volume
| 54 | |
| 5 | Author
| C. G. Rossi, O. R. Aym Ond, C. Sanlaville-Boisson, M. Jay, Si Cedric | Requires cookie* | | | Title
| Rosa Taxonomy and Hierarchy of Markers Defined by ACT STATIS | | | | Abstract
| , L ab o rato ire de Biologie M icrom oleculaire e t Phytochim ie, U niversite C laude B ernard Lyon I, 43, bd du 11 novem bre 1918, 69622 V illeurbanne C edex, France Z. N aturforsch. 54c, 2 5 -3 4 (1999); received July 10/Septem ber 7, 1998 ACT-STATIS M ethod, M arkers H ierarchy, M ultivariate Analysis, Rosa Taxonom y The A C T STATIS m ethod, a m ulti-table com parison, was applied to 62 Rosa species to be clustered into four sections (C arolinae, C innam om eae, Pim pinellifoliae and Synstylae); the d ata sets were dealing with m orphology (15 criteria), anthocyanin p a tte rn (10 com pounds), flavonol heteroside p attern (26 com pounds) and superoxide dism utase isozyme (SO D) polym orphism (11 bands). This m ethod ap p eared very pow erful to recognize the rose sections and to set up a m ark er hierarchy which places at the first level the flavonol h e tero side pattern, then the m orphological d ata, the SO D isozyme d ata and finally the anthocyanin pattern. The correlation studies betw een the m arkers underlin ed th e relatively com m on view by m eans of flavonol p attern s and the m orphological features. | | | |
Reference
| Z. Naturforsch. 54c, 25 (1999) | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0025.pdf | | | | Identifier
| ZNC-1999-54c-0025 | | | | Volume
| 54 | |
| 7 | Author
| | Requires cookie* | | | Title
| Alkylresorcinol Homologs in Pisum sativum L. Varieties | | | | Abstract
| R o b ert Z arnow ski and A rkadiusz K ozubek* D ep artm en t of Lipids and Liposom es, Institute o f B iochem istry and M olecular Biology, U niversity of W roclaw, W roclaw. Poland Z. N aturforsch. 54c, 4 4 -4 8 (1999); received A ugust 6 /O cto b er 12, 1998 Alkylresorcinols, C ardol H om ologs, Pea, P isum , Legum inaceae A cetone extracts from the seeds o f Pisum sativum L. sensu lato (L egum inoseae) separated by thin layer ch rom atography revealed the occurrence o f bands with ch rom atographic m obil ity and color reaction with Fast B lue B ch aracteristic for l,3-dihydroxy-5-alkylbenzenes. These polyketide m etabolites have b een isolated and identified by spectroscopic means. The occurrence of hom ologous series o f satu ra te d (approxim ately 70%) and enoic (m ono and diunsaturated) hom ologs with chain length of C15 to C25 has been revealed with C17 as the m ain homolog. | | | |
Reference
| Z. Naturforsch. 54c, 44 (1999) | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0044.pdf | | | | Identifier
| ZNC-1999-54c-0044 | | | | Volume
| 54 | |
| 8 | Author
| Claude Aflalo3, Wang Bingb, AlizaZ. Arkab, Sammy Boussibab | Requires cookie* | | | Title
| The Effect of the Herbicide Glufosinate (BASTA) on Astaxanthin Accumulation in the Green Alga Haematococcus pluvialis | | | | Abstract
| Haematococcus pluvialis, Astaxanthin, Glufosinate. BASTA, Methionine-S-sulfoximine (MSX), Glutamine Synthetase (GS) The addition of 2.5 mM glufosinate ammonium (BASTA), a well known plant killer, to Haematococcus pluvialis culture efficiently inhibits cell growth, blocks the activity of gluta mine synthetase (GS) and induces astaxanthin accumulation. Conversely, methionine-S-sul-foximine (MSX), a well known GS inhibitor, had no effect on neither these parameters. When GS activity was tested in vitro, MSX inhibited the activity at high concentrations (mM), while glufosinate was effective in the |.im range. We have found that in the presence of glufosinate, ammonia is excreted from the cells. Therefore, we suggest that this process enables Haematococcus cells to escape the potentially harmful effect of glufosinate. As a consequence of the inability to assimilate nitrogen, astaxanthin is accumulated. This situation resembles the response of Haematococcus cells to nitrogen starvation. | | | |
Reference
| Z. Naturforsch. 54c, 49—54 (1999); received September 18/October 19 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0049.pdf | | | | Identifier
| ZNC-1999-54c-0049 | | | | Volume
| 54 | |
| 9 | Author
| FrankI. Bohnenstengel3, KlausG. Steubeb, CorinnaM. Eyerb, BambangW. Nugroho3, PhamD. Hungc, LeC. Kietd, Peter Proksch3 | Requires cookie* | | | Title
| Structure Activity Relationships of Antiproliferative Rocaglamide Derivatives from Aglaia Species (Meliaceae) | | | | Abstract
| Eleven rocaglamide derivatives (cyclopentatetrahydrobenzofurans) and one structurally related aglain congener all isolated from different Aglaia species (Meliaceae) were tested for growth inhibiting properties using the human cancer cell lines MONO-MAC-6 and MEL-JUSO. Proliferation of both cell lines was efficiently inhibited in a dose and compound de pendent manner. Applying a MTT-Assay, the IC50 of the most active compound didesmethyl-rocaglamide (1) was observed at 0.002 and 0.006 [ig/ml (0.004 and 0.013 j.iM) depending on the cell line investigated. Bulky aminoacyl substituents at C-2, acetylation of the OH substitu ent at C-l or insertion of a OH or OMe substituent at C-3 of the rocaglamide skeleton all diminished the activity of the compounds investigated. The aglain derivative 12 was inactive up to a concentration of 3 ng/ml (4.6 [ . i m) . This loss of activity is assumed to be mainly due to the presence of a pyran ring in the aglains vs. a furan ring as found in rocaglamide derivatives. Rocaglamide derivatives may act primarily by inhibition of cell proliferation as evidenced by the absence of a significant cytotoxic effect in long-term cultures of MONO-MAC-6 cells treated with high doses of didesmethylrocaglamide. O ur data suggest that rocaglamide derivatives could exert a potential role in the treatm ent of malignant diseases and are worth to be investigated in further studies of experimental medicine and pharmacology. | | | |
Reference
| Z. Naturforsch. 54c, 55—6 (1999); received September 28/October 21 1998 | | | |
Published
| 1999 | | | |
Keywords
| Aglaia spp, Meliaceae, Rocaglamide, Cyclopentatetrahydrobenzofurans, Antiproliferative Activity, Cancer Cells, M ONO-M AC-6 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0055.pdf | | | | Identifier
| ZNC-1999-54c-0055 | | | | Volume
| 54 | |
| 11 | Author
| Daniela Todorova3, Maria Tupova3, Veneta Zapreva3, Tsenka Milkova3, Atanas Kujumdjievb | Requires cookie* | | | Title
| Transformation of Aminosteroids into Pharmacologically Active Amides of Phenolic Acids | | | | Abstract
| 5ct-cholestan-3ß-yl-amine, 5a-cholestan-3a-yl-amine, 3a-and 3ß-amino-(2'-aminoethyl)-cholest-5-en. Amides of Cinnamic Acid Derivatives, Antibacterial Activity Amides of cinnamic acid derivatives with 3a-and 3ß-cholestanylamines, as well as with 3a-and 3ß-amino-(2'-aminoethyl)-cholest-5-en were synthesized using dicyclohexylcarbodiimide (DCC) and 1-hydroxy-benzotriazole as efficient additives. Their structure was determined by UV and 'H N M R . 3ß-Amino-(2'-aminoethyl)-cholest-5-en, amides of p-hydroxy-cinnamic acid 4 and 9, and N-cholest-5-en-3a-aminoethyl-di-(3',-phenyl-trans-2,'-propene)-am ide 10 showed moderate antibacterial activity against Staphylococcus aureus. | | | |
Reference
| Z. Naturforsch. 54c, 65—69 (1999); received July 28/October 14 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0065.pdf | | | | Identifier
| ZNC-1999-54c-0065 | | | | Volume
| 54 | |
| 12 | Author
| Helvi Kaatz3, Katrin Strefferb, UllaW. Ollenbergerh, MartinG. Peter3 ' | Requires cookie* | | | Title
| Inhibition of Mushroom Tyrosinase by Kojic Acid Octanoates | | | | Abstract
| Octanoic acid 2-hydroxymethyl-4-oxo-4//-pyran-5-yl ester (kojic acid 5-O-capryloate, 2), octanoic acid 4-oxo-2-(l-oxooctyloxymethyl)-4//-pyran-5-yl ester (kojic acid 5,7-di-O-di-capryloate, 3), and octanoic acid (5-hydroxy-4-oxo-4//-pyran-2-yl)-methyl ester (kojic acid 7-O-capryloate. 5) were prepared from 5-hydroxy-2-hydroxymethyl-4//-4-pyrone (kojic acid, 1) and caprylic acid. We also describe the synthesis of 11-aminoundecanoic acid (5-hydroxy-4-oxo-4//-pyran-2-yl)-methyl ester (6). In solution, the monoesters are non-competitive in hibitors of mushroom tyrosinase (EC 1.14.18.1) (2: IC50 = 107 jiM, 5: IC5 0 = 15 jam, 6 : IC50 = 20 [.im; cf. 1: IC50 = 45 [.im, mixed type inhibition). When tyrosinase is immobilized in a polyvi-nylalcohol membrane, 5 is a weaker inhibitor than 1 or 2. | | | |
Reference
| Z. Naturforsch. 54c, 70—7 (1999); received June 15/October 27 1998 | | | |
Published
| 1999 | | | |
Keywords
| Kojic Acid, Enzyme Inhibitors, Mushroom Tyrosinase, Caprylic Acid co-Aminofatty Acids | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0070.pdf | | | | Identifier
| ZNC-1999-54c-0070 | | | | Volume
| 54 | |
| 13 | Author
| IvankaG. Stankova3, M. Ario, F. Simeonovb, Vera Maximova0, AngelS. Galabov0, EvgenyV. Golovinskyd | Requires cookie* | | | Title
| Synthesis and Anti-Virus Activity of Some Nucleosides Analogues | | | | Abstract
| New 3'-, 5'-, 5-bromo-2'-deoxyuridine (3 a -g) and 3'-, 5'-thymidine (4 a -i) analogues with amino acid and peptide residues were synthesized and evaluated for antiviral activity. The influence of long peptide chains, essential amino acids and the effect of this structural modifi cation on the antiviral activity has been also reported. Three 5-bromo-2'-deoxyuridine derivatives containing glycyl-, glycyl-glycyl-and glycyl-gly-cyl-glycyl-residues (3a, 3b, 3c) showed a strong activity against the herpes virus PsRV and a moderate one vs. HSV-1. The corresponding thymidine analogues were considerably less effective, and only com pounds 4d and 4h showed a borderline effect against PsRV. | | | |
Reference
| Z. Naturforsch. 54c, 75—83 (1999); received August lO/October 20 1998 | | | |
Published
| 1999 | | | |
Keywords
| 5-Bromo-2'-Deoxyuridine, Thymidine, Amino Acids, Peptides, Antiherpes Activity | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0075.pdf | | | | Identifier
| ZNC-1999-54c-0075 | | | | Volume
| 54 | |
| 14 | Author
| Hans Eckstein, Birgit Flügge | Requires cookie* | | | Title
| Guanosine 3':5'-Cyclic Monophosphate -Dependent Particulate Protein Kinase Activity from Yeast (Saccharomyces cerevisiae) | | | | Abstract
| Protein Kinase. cGMP. Yeast Continuing our studies on cGMP in growing yeast we detected a particulate cGMPdepen-dent protein kinase (Pk-G), which was solubilized by detergents and NaCl. It achieves maxi mum activity at 25 °C and pH = 6 .8 , high concentrations of substrate proteins or cGMP produce saturation. Casein and histones are appropriate substrates, phosphatase-pretreated histone H-2a provokes outstandingly high activity. Pk-G differs from cAM P-dependent pro tein kinase (Pk-A) with respect to pH optimum, tem perature tolerance above 50 °C, and stability. Partial purification is achieved by chromatography with DEAE-cellulose, Sepharose, and cGMP-substituted Sepharose. The latter step also markedly removes Pk-A. At least three proteins with Pk-G-activity and high cGMP-affinity are separated by polyacrylamide-gel-electrophoresis. Their apparent molecular masses, as deduced from comigrating marker proteins, differ considerably from those of other Pk-G's. but also of Pk-A's. | | | |
Reference
| Z. Naturforsch. 54c, 84—93 (1999); received O ctober 6 /O ctober 27. 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0084.pdf | | | | Identifier
| ZNC-1999-54c-0084 | | | | Volume
| 54 | |
| 15 | Author
| Satoshi Nishino, Teruyuki Kobayashi, Mami Kunita, Sayo Ito, Yuzo Nishida | Requires cookie* | | | Title
| Structural Variety of Copper(II)-Peroxide Adducts and Its Relevance to D N A Cleavage | | | | Abstract
| Copper(II)-peroxide Adduct, DNA Cleavage, Effect of Peripheral Group The reactivity of copper(II) compounds with several tetradentate ligands towards some spin-trapping reagents was studied in the presence of hydrogen peroxide. The compounds used in this study are roughly divided into two groups based on the reactivity towards 2 ,2 ,6 ,6 -tetramethyl-4-piperidinol(and also 2,2,6,6-tetramethyl-4-piperidone), which are trapping agents for singlet oxygen, 10 2 (1 Ag); The A-group compounds exhibited a high activity to form the corresponding nitrone radical, which was detected by ESR spectroscopy, but corre sponding activity of the B-group compounds was very low. The A-group compounds defined as above exhibited high activity for cleavage of DNA(supercoiled Form I) in the presence of hydrogen peroxide, yielding DNA Form II (relaxed circular) or Form III (linear duplex) under our experimental conditions ([Cu(II)]=0.1 —0.5 mM). On the other hand, the B-group compounds effected complete degradation of the DNA (double-strand scission) under the same experimental conditions, formation of Form II or Form III DNA was negligible. Two different DNA cleavage patterns observed for A-and B-group compounds were elucidated by the different structural property of the copper(II)-peroxide adducts, which is controlled by the interaction through both DNA and the peripheral group of the ligand system. | | | |
Reference
| Z. Naturforsch. 54c, 94—99 (1999); received August 4/October 16 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0094.pdf | | | | Identifier
| ZNC-1999-54c-0094 | | | | Volume
| 54 | |
| 16 | Author
| Celso Caruso-Neves3, Marcelo Einicker-Lamasb, Carlos Chagas3, Mecia Maria, Adalberto Vieyrac, AnfbalGil Lopes3 | Requires cookie* | | | Title
| Ouabain-Insensitive Na+-ATPase Activity in Trypanosoma cruzi Epimastigotes | | | | Abstract
| N a+-ATPase, T. cruzi, ATPase, Epimastigote, Furosemide In the present paper, the presence of a ouabain-insensitive N a+-stimulated, Mg2 +-depen-dent ATPase activity in T. cruzi epimastigotes CL14 clone and Y strain was investigated. The increase in N a+ concentration (from 5 to 170 mM), in the presence of 2 mM ouabain, increases the ATPase activity in a saturable manner along a rectangular hyperbola. The was 18.0 ± 1.0 and 21.1 ± 1.1 nmoles Pi x mg-1 x m in-1 and the half-activation value (K50) for Na+ was 34.3 ± 5.8 mM and 37.7 ± 5.3 in CL14 clone and in Y strain, respectively. The N a+-stimulated ATPase activity was inhibited by 5-[aminosulfonyl]-4-chloro-2-[(2-furanylmethyl)-amino] benzoic acid (furosemide) in a dose-dependent manner. The half-inhibition value (I50) was 0.22 ± 0.03 and 0.24 ± 0.07 mM, and the Hill num ber (n) was 0.99 ± 0.2 and 2.16 ± 0.29 for CL14 clone and Y strain, respectively. These data indicate that both cell types express the ouabain-insensitive Na+-ATPase activity, which might be considered the bio chemical expression of the second Na+ pump. | | | |
Reference
| Z. Naturforsch. 54c, 100—104 (1999); received Septem ber 22/October 27 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0100.pdf | | | | Identifier
| ZNC-1999-54c-0100 | | | | Volume
| 54 | |
| 17 | Author
| Narayanan Rajendran | Requires cookie* | | | Title
| Identification and Cloning of a Gene Locus Encoding Peptide Synthetase of Pseudomonas fluorescens by Two Sets of PCR Primers | | | | Abstract
| A chromosomal locus encoding biosynthetic genes for a putative peptide synthetase of Pseudomonas fluorescens was identified and cloned. To achieve this, two sets of degenerated oligonucleotide primers KAGGA:SGTTG and TG D :LG G were used in PCR. These primers were selected based on highly conserved units of known peptide synthetases involved in adenylation and thiolation regions of Bacillus subtilis. The discrete amplified bands from PCR ca. 300 bp for KAGGA:SGTTG and ca. 500 bp for TGDrLGG proved to be integral part of the genomic DNA of P. fluorescens were cloned and sequenced. Sequence alignments of both fragments confirmed the putative peptide synthetase genes in P. fluorescens. The present study describes the identification and cloning of peptide synthetase genes of P. flu o rescens, which can be used to identify a genetic locus encoding peptide synthetase in other microbial species. | | | |
Reference
| Z. Naturforsch. 54c, 105—109 (1999); received August 26/September 21 1998 | | | |
Published
| 1999 | | | |
Keywords
| Oligonucleotide Primers, Pseudomonas fluorescens, Peptide Synthetase, Identification | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0105.pdf | | | | Identifier
| ZNC-1999-54c-0105 | | | | Volume
| 54 | |
| 18 | Author
| JamesE. Flanigan, G. Erd Gäde | Requires cookie* | | | Title
| On the Release of the Three Locust (Locusta migratoria) Adipokinetic Hormones: Effect of Crustacean Cardioactive Peptide and Inhibition by Sugars | | | | Abstract
| A dipokinetic horm one. C rustacean cardioactive peptide. C orpora cardiaca. Locust. A n existing test to m o n ito r the rate of adipokinetic horm one release from the c o rp o ra cardiaca (C C) of Locusta migratoria in vitro was im proved, so th at a constant basal rate of release was achieved and the am o u n t of released L om -A K H -I, II and III could be qu an tified by H PLC . This test system was subsequently used to dem onstrate th at a small peptide, which has b een found in a few insect species including L. migratoria, crustacean cardioactive p e p tide (C C A P), induces release o f all th ree AKH s. M oreover, 80 mM trehalose reduces C C A P -induced release of A K H s in vitro, and 160 mM glucose reduces this release even fu rth er. G lucose also had a g reater inhibitory effect than trehalose on the spontaneous release and inhibited the high potassium -stim ulated release of A K H from the CC in vitro. E ighty mM sucrose, on the o th e r hand, had no effect on the release of A K H . The effect of treh alo se and glucose could be due to th eir use as an energy source, with trehalose first having to be co nverted to glucose. W hatever the stim ulus, the three A K H s are released in the sam e p ro portions as they are found in the CC, which in vivo would m ake L om -A K H -I, th e m ost ab u n d an t A K H , the m ajor effector of the biological effects of A K H s in adult locusts. | | | |
Reference
| Z. Naturforsch. 54c, 110 (1999); received June 3/A ugust 21 1998 | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0110.pdf | | | | Identifier
| ZNC-1999-54c-0110 | | | | Volume
| 54 | |
| 20 | Author
| Thomas Burger, ElmarW. Lang | Requires cookie* | | | Title
| An Incremental Hebbian Learning Model of the Primary Visual Cortex with Lateral Plasticity and Real Input Patterns | | | | Abstract
| R egensburg, G erm any Z. N aturforsch. 54c, 1 2 8 -1 4 0 (1999); received A ugust 3/Septem ber 25, 1998 N eural N etw ork. H eb b ian L earning, Visual C ortex, L ateral Plasticity, S elf-O rganization We presen t a sim plified b inocular n eural netw ork m odel of the prim ary visual cortex w ith sep arate O N /O F F -pathw ays and m odifiable afferent as well as intracortical synaptic c o u plings. R andom as well as n atu ral im age stim uli drive the weight a d ap ta tio n which follows H ebbian learning rules stabilized with constant norm and constant sum constraints. The sim u lations consider the dev elo p m en t of o rien tatio n and ocular dom inance m aps un d er d ifferen t conditions concerning stim ulus p attern s and lateral couplings. W ith random input p a tte rn s realistic o rien tatio n m aps with ± 1 /2 -vortices m ostly develop and plastic lateral couplings self-organize into m exican hat type structures on average. U sing natural greyscale im ages as input patterns, realistic o rien tatio n m aps develop as well and the lateral coupling profiles of the cortical n eu ro n s rep resen t the tw o point correlations of the input im age used. | | | |
Reference
| Z. Naturforsch. 54c, 128 (1999) | | | |
Published
| 1999 | | | |
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| default:Reihe_C/54/ZNC-1999-54c-0128.pdf | | | | Identifier
| ZNC-1999-54c-0128 | | | | Volume
| 54 | |
|
