bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lateral Inhibition in the Com pound Eye of the Fly, Musca
Authors: Kirschfeld K. , Lutz B. 
Published: August 2018

Abstract
Lateral Inhibition, Compound Eye, Fly Lateral inhibition is a common phenomenon in the eyes of vertebrates as well as of invertebrates. Indications of lateral inhibitory interactions in dipteran eyes have been found by means of electro-physiological techniques*' 2. It was not possible,
Gravitational Stimulations Inhibit Oscillatory Growth Movements of Plants
Authors: Johnsson Anders 
Published: August 2018

Abstract
Spontaneous oscillatory growth movements around (or across) the plumb line occur in young sunflower seedlings. The period is about 2.5 h. When such plants are tilted 90° and continuously rotated around their axis with a speed of 0.5 rpm, the oscillatory spontaneous movements cease. The findings are interpreted as supporting a previously published model for gravitationally induced plant movements.
A Comparison of the Methods of Molt Staging According to Drach and to Adelung in the Common Shore Crab, Carcinus maenas
Authors: Spindler Klaus-Dieter , Adelung Dieter , Tchernigovtzeff Catherine 
Published: August 2018

Abstract
Molt stages of juvenile Carcinus maenas were determined independently according to the methods of Drach and of Adelung. With the exception of stage DO the two systems agree rather well over the whole intermolt cycle. The molting hormone contents of animals regenerating several lim bs and whose molt stages were determined according to Drach are in the same range as the values published by Adelung.
Notizen: Spezifische Verbindungsstrukturen der Faserzellen von Trichoplax adhaerens F. E. Schulze/Special Connecting Structures between Fiber Cells of Trichoplax adhaerens F. E. Schulze
Authors: Schulze F , Schulze F , Grell Karl , Benwitz Gertrud 
Published: August 2018

Abstract
In the primitive metazoan, Trichoplax adhaerens, the fiber cells are responsible for the change of shape. Electron microscopy reveals connections between protoplasmic strands of neighbouring cells marked by an osmiophilic disc-like structure. Possible functions are discussed.
Small-Angle X-Ray Scattering Studies of 1/10-Size and 1/20-Size Molecules of Helix pomatia α-Hemocyanin
Authors: Pilz Ingrid , Walder Karin , Siezen Roland 
Published: August 2018

Abstract
The small-angle X-ray scattering of 1/10-size molecules (in 0.1 ionic strength Tris buffer pH 8.1) and 1/20-size molecules (in 0.1 ionic strength ethanolamine buffer pH 10.6) of α-hemocyanin of the snail Helix pomatia was studied.
The radii of gyration, 8.7 nm and 8.0 nm for 1/10-size and 1/20-size molecules respectively, and the shape of the scattering curves indicate that both have a very anisotropic shape. Comparison of the experimental scattering curve of 1/10-size molecules with theoretical scattering curves gives the best agreement for flat cylinders or quadratic prisms the diameter respectively side of which is about 10 times larger than the height (dimensions side = 21 nm, height 2 nm). The scattering curves of various models composed of larger and smaller subunits were calculated; the best agree­ment was found also for flat models of similar dimensions.
Die Synthese von Lipochinonen und isoprenoiden Pigmenten bei der Ergrünung von Etioplasten im Blaulicht / Synthesis of Lipoquinones and Isoprenoid Pigments during Greening of Etioplasts in Blue Light
Authors: Kleudgen Hans , Lichtenthaler Hartmut 
Published: August 2018

Abstract
Blue light induces in etioplasts of Hordeum seedlings parallel to the formation of chlorophyll an increased synthesis of carotenoids, plastidic benzoquinones and vitamin K1.
1. Blue light induces an enhanced synthesis of β-carotene, lutein, violaxanthin, and neoxanthin, while the levels of antheraxanthin and zeaxanthin are decreased.
2. In contrast to the etiolated tissue a much higher portion of total plastoquinone-9 (oxidized and reduced form) is formed in blue light than total α-tocopherol (+ α-tocoquinone), and a higher portion of the oxidized quinone forms plastoquinone-9 and α-tocoquinone.
3. The blue-light-induced changes of the isoprenoid lipid synthesis described here are similar to those obtained in continuous far-red light. It is, therefore, suggested that blue light is effective via the blue absorption bands of the phytochrome system.
4. Blue-light-induced greening of etioplasts results in a much higher synthesis rate of chlorophyll a and other isoprenoid thylakoid lipids as compared to red light. This enhancement of thylakoid lipid formation appears to be a special blue light effect.
Zur Bedeutung der "richtigen" Syntax auditiver Muster für deren vokale Beantwortung durch Amseln / On the Relevance of the "Right" Syntax of Auditory Patterns to Vocal Responses of Blackbirds
Authors: Todt Dietmar 
Published: August 2018

Abstract
Male blackbirds (Turdus merula) were confronted with recordings of normal and experimentally modified song-phrases of their own repertoire. I tested the characteristics of the equivalent vocal responses (= stimulus A → vocalization A) of the birds. As I found the "right" (= the indivi­dually known) syntax (= sequential order) of the elements (= notes) of the phrases were an essential condition for these responses. The different elements (notes) of a phrase took part in the facilitation of the vocal responses particularly (Fig. 1A) . - Phrases modified in their syntax proved to be ineffective in the above mentioned sence; even if the modification remained inside the conspecific range of individual differences between blackbirds. The onset of the ineffectiveness started at that point of the stimuli at which the syntactic modification began (Fig. 1 B, C). However, after an experimental period of 20 days most of the modified phrases (presented to the birds about 100 times per day) began to become effective, that means: to facilitate equivalent vocal responses (Fig. 2). - I concluded that the birds possess a "syntactic filter" which interacts with the genera­ tion of specific vocal reactions on the auditory stimuli. The results show that this filter can be modified.
Anthraquinones of Certain Egyptian Asphodelus Species
Authors: Hammouda F.M. , Rizk A.M. , El-Nasr M.M. Seif , Asr El-N 
Published: August 2018

Abstract
The study of the anthraquinones of Asphodelus fistulosus and A. microcarpus resulted in the isolation of chrysophanol, aloe-emodin, anhydrorugulosin, three others bianthraquinones (the cleavage products of which are either 1 ,8 -dehydroxyanthraquinone or chrysophanol) and chrysophanol-8 -mono-β-ᴅ-glucoside. The obtained results revealed a qualitative difference in the anthraquinone content of the different parts (leaves, seeds and tubers).
Bildung eines oxoäthylverzweigten Zuckers aus Thymidindiphosphatglucose und Pyruvat mit einem zellfreien. System aus Streptomyces aureofaciens / Formation of an Oxoethyl-branched Sugar from Thymidine Diphospho-ᴅ-glucose and Pyruvate with a Cell Free System from Streptomyces aureofaciens
Authors: Matern Ulrich , Grisebach Hans 
Published: August 2018

Incubation of thymidine diphospho(TDP)-ᴅ-[U-14C] -glucose with a cell-free extract from Streptomyces aureofaciens and subsequent hydrolysis of the nucleotide sugars led to the formation of 4 radioactive products (I -IV ). Addition of pyruvate to the incubation caused an increase in the amount of I I I and a decrease in that of II. Product I was identified as 4-keto-6-deoxyglucose. Product III was isolated on a preparative scale as the methylglycoside and was identified as α-methyl- 2,6-dideoxy-4-C-[1'-oxoethyl]-ʟ-lyxo-hexopyranoside (Fig. 1, 3) from its NM R spectrum and by its borate complex formation, which established the cis configuration of the hydroxyl groups at C-3 and C-4. The oxoethyl-branched sugar formed in the cell-free system is epimer at C-3 with the sugar formed in vivo by S. aureofaciens. The reason for this difference is not clear. Product II could be tentatively formulated as 4-keto-2,6-dideoxy-ʟ-lyxo-hexopyranose (6 ) on the basis of its chromatographic and chemical properties and its reduction by sodiumborohydride to two sugars. The products II - IV were also obtained when TDP-4-keto-6-deoxyglucose was the substrate of the reaction.
Addition of thiaminepyrophosphate to the incubation in the presence of pyruvate did not increase the yield of III . The increasf in the amount of III formed in the presence of pyruvate could be inhibited by addition of glyoxylic acid. After incubation of [α-14C]-hydroxethyl-thiaminepyrophosphate with TDP-glucose in the cell-free extract no radioactive III could be detected.
Bestimmung von Spurenelementen in menschlicher Haut / Determination of Trace Elements in Human Skin
Authors: Feuerstein H , Oschinski J 
Published: August 2018

Abstract
The elements Cu, Ag, Au, Cr, Fe, Zn, As, Mo and W have been determined in human skin using the neutron activation technique. The values are compared to values published in the literature. The values are scattering over a wide range, leading to the assumption of an uneven distribution of the trace elements in human skin. From the results of a special sample it is concluded that carrying a golden ring over a longer period of time will not contaminate the skin by gold or copper. The investigation of a skin sample where gold has been plated out showed a maximum of the gold concentration beneath the skin surface.
Versuche zur lysosomalen Zytolyse-Kettenreaktion der Krebszellenschädigung / Experiments to the Lysosomal Cytolysis Chain Reaction of Cancer Cells Damage
Authors: Ardenne M. von , Reitnauer P. G. 
Published: August 2018

After explaining the significance of a cytolysis chain reaction within the set of problems encountered in cancer therapy, all our previous studies on the lysosomal chain reaction and its problems are summarized. It follows a report on a new fundamental in vitro test showing that, at pH = 5.8, T = 42 °C and in cell suspensions with high cell volume portion (ƐZ = 4 0 · 10-3), EMAC cells are damaged very much quicker than in suspensions of only low cell volume (ƐZ = 2·10-3). Furthermore, there is an increase in acidic phosphatase in the suspension milieu of high cell densities. In addition, it can be pointed out that the observed damaging of cells is closely linked with the complete inhibition of glucose metabolism.
The described findings are to be taken as a strong circumstantial evidence for the efficiency of cell damaging chain reactions.
Serotonine-Nucleotide Interaction Studied by PMR. Explanation of the Variability in Association Constants Obtained from Chemical Shifts of Different Protons
Authors: Lawaczeck R , Wagner K 
Published: August 2018

Abstract
A study of the association of serotonine with 5'-AMP by PM R spectroscopy is described. The association constants obtained from the chemical shift of non-equivalent protons show considerable variation outside experimental error, a fact which wT as reported by several authors. To support the suppositon that small amounts of complexes of different stoichiometry, — which in general can hardly be detected — , are responsible for this phenomenon, computer simulation of various hypo­ thetical systems were investigated. The results clearly demonstrate that the neglect of minor fractions of complexes of different stoichiometries lead to significant variation in the association constants calculated for different protons, provided that these protons experience different magnetic enviro-ments in the different complexes.
Chlorophyll a and Cytochrome c at a Heptane-Water Interface
Authors: Karan Jeffrey , Brody Seymour Steven 
Published: August 2018

Abstract
The surface pressure was measured as a function of area/molecule for chlorophyll a (Chl) and cytochrome c (Cyt) at a heptane-water interface. At a surface pressure of 6 dyn/cm the area per molecule of Chl(A6) = 113 ± 6 Å2, for reduced Cyt c (red. Cyt) the A6 = 5000 ± 300 Å2 and for oxidized Cyt c (ox. Cyt) A6= 4100 ± 250 Å2. Cyt appears to denature at the interface. Irradiation results in a decrease of the A6 for Chl to A6= 100 ± 5 Å2. There appears to be interaction between Chi and red. Cyt in a mixed film no interaction is observed between Chi and ox. Cyt
Involvement of the Superoxide Free Radical Ion in Photosynthetic Oxygen Reduction
Authors: Elstner Erich F. , Heupel Adelheid 
Published: August 2018

Abstract
Photosynthetic oxygen reduction by isolated chloroplast lamellar systems has been studied with the aid of superoxide dismutase. Two mechanisms of oxygen reduction by illuminated chloroplast lamellar systems can be differentiated:
1. In the presence of low potential electron acceptors like AQ or MV the superoxide free radical ion is the product of autooxidation of the reduced acceptor. Addition of superoxide dismutase has no influence on the initial rates of oxygen reduction.
2. Stimulation of photosynthetic oxygen reduction by o-diphenols is only observed in the absence of superoxide dismutase and ascorbate; apparently the superoxide free radical ions is involved in both initiation and propagation of a chain reaction.
If the ferredoxin-stimulated photosynthetic oxygen reduction is measured, both ascorbate and superoxide dismutase are active as inhibitors. By heating suspensions of chloroplast lamellar systems, a substance is released into the supernatant which exhibits the activity of an oxygen reducing factor (ORF) with properties similar to o-diphenols: The stimulation of photosynthetic oxygen reduction is reversed by addition of either SDM or ascorbate. A reaction sequence for photosynthetic oxygen reduction in the presence of ferredoxin is considered, which is initiated by the superoxide free radical ion produced by autooxidation of reduced ferredoxin; the superoxide free radical ion "activates" an endogenous oxygen reducing factor, which in this "active" state can reduce oxygen to O2·-. The presence of either superoxide dismutase or ascorbate yields in chain termination by scavenging the superoxide free radical ion
Gamma Irradiation of Uridine and Uridylic Acid in Aerated A queous Solutions: Identification of the Major Product
Authors: Ducolomb R , Cadet J , Teoule R 
Published: August 2018

Abstract
The major product of uridine gamma irradiation in aerated aqueous solution (10-3 ᴍ, pH ~6) has been identified: N-(β-ᴅ-ribofuranosyl) -formamide. Thin-layer silica gel chromatography and spectroscopic methods (mass spectrometry. NMR, IR, optical rotation) enabled us to isolate and characterize this product.
It may be assumed that this substance resulted from the hydrolytic degradation of unstable hydroxy-hydroperoxides. It was also prepared by uridine oxydation with pertrifluoracetic acid.
A similar major compound in the radiolysis of uridylic acid has been found
Influence of the pH in the OH Radical Attack on the Pyrimidic Ring
Authors: Teoule R , Cadet J 
Published: August 2018

Abstract
The attack of OH radical on pyrimidic ring preferential­ ly took place at position 5 at neutral pH and at position 6 at low acidic pH. The trans isomers were always the major products. These conclusions arose from studies involving comparison with synthetic peroxides: c£s-6-hydroperoxy-5-hydroxy-5,6-dihydrothymine (1), as-5-hydroperoxy-6-hydro-xy-5,6-dihydrothymine (2) , frans-6-hydroperoxy-5-hydroxy-5.6-dhydrothymine (3) and ?rans-5-hydroperoxy-6-hydroxy-5.6-dihydrothymine (4) .
The NMR coupling constants of the OH-6 proton with H-6 allowed us to assign unambiguously the structures of these peroxides in agreement with 18O mass spectrometry results. G radiolytic values and NMR data are given
Charge Transfer Interactions between Isonicotinic Acid Hydrazide and Cupric Ions
Authors: Hillerbrand M. , Lohmann W. , Penka V. , Ehling U. 
Published: August 2018

Abstract
The interaction of Cu2+ with isonicotinic acid hydrazide (INH) and some of its derivatives has been investigated by means of electron spin resonance, nuclear magnetic resonance, and optical absorption studies. It could be shown that an interaction exists between the metal ions and the hydrazine side chain in addition to the very weak interaction with the ring nitrogen. The results obtained indicate the formation of a charge transfer complex.
Electronic Structure and Spatial Arrangement of C2v-Coordinated Ferric Iron in Metmyoglobin, Metmyoglobin Fluoride, and Methemoglobin
Authors: Eicher Hermann 
Published: August 2018

Abstract
Electronic Structure, Metmyoglobin, Metmyoglobin Fluoride, Methemoglobin The electronic term scheme of ferric iron in metmyoglobin, metmyoglobin fluoride, and met­ hemoglobin is evaluated by a Hamiltonian which involves the Coulomb repulsion of the 3d electrons, their interaction with the C2v-coordinated ligands, and spin-orbit coupling. The adjustable parameters of the theory were determined by a least squares fit to experimental EPR, susceptibility, and far-infrared data reported in the literature. According to these results, the structural properties of the ferric ion and its neighboring ligands were discussed by means of group theoretical arguments: An increasing out of plane position of the ferric ion is found in the sequence metHb- metMb -MbF which corresponds to an increasing binding strength with the axial ligands.
Gas Chromatographie Determination of Subnanogram Amounts of the Juvenile Hormone Methyl (2E, 6E)-10,ll-epoxy-3,7,ll-tri- methyl-2,6-dodecadienoate (JH III) in Insect Material by Electron Capture Detection
Authors: Van Broekhoven L , Van Der Kerk A , Hoof -Van , Salemink C 
Published: August 2018

Abstract
Using an electron capture detector, a sensitive gas chromatographic method has been developed for the determination of the juvenile hormone methyl(2E, 6E)-10, 11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate (JH III) in insect material. The sensitivity in electron capture detection of the bisheptafluorobutyrate was determined. The work-up procedure was checked by adding known amounts of JH III to insect material. The method seems equally applicable to all three juvenile hormones.
Ribose Conformations in the Common Purine(ß)ribosides, in Some Antibiotic Nucleosides, and in Some Isopropylidene Derivatives: A Comparison
Authors: Westhof Eric , Röder Oskar , Croneiss Ingrid , Lüdemann Hans-Dietrich 
Published: August 2018

Abstract
With the use of PMR the ribose conform ations have been studied in the tem perature range - 60 to + 40 °C in ND3 solutions of adenosine (A), guanosine (G), inosine (I), xanthosine (X), purineriboside (P R), 2-am inopurineriboside (2am P R), N6-isopentenyladenosine (N6ipA), 8-bromo-adenosine (8-BrA), 8-bromoguanosine (8-BrG), formycin B (F), tubercidin (T), isopropylidene-adenosine (iA), and isopropylideneguanosine (iG). The analysis is based on the two-state S ⇄ N model of the ribose m oiety proposed by Altona and Sundaralingam . The compounds studied can be classified into two groups: 1. A, I, G, X, PR , 2am PR, N6ipA, and T show a small tem perature dependence of the S ⇄ N equilibrium and [ S ] ~ 0 .6 ; 2. 8-BrA, 8-BrG, and F have a stronger tem perature dependence and [S] ~ 0 .8 . W ithin these two groups the sim ilarities observed are greater than observed in the solid state. Some therm odynam ic conclusions about the S ⇄ N and the syn ⇄ anti equilibria are presented. The results support the previously proposed correlation of the S state of the ribose with the syn conform ation of the base and of the N state of the ribose with the anti conform ation of the base. Furtherm ore, it is derived that the gg rotam er is correlated with the S state of the ribose and therefore stabilizes the syn conformation of the base.
Temperature Sensitive Events between Photoreceptor and Circadian Clock?
Authors: Hamm Ursula , Aroli M , Chandrashekaran K , Olfgang Engelmann W 
Published: August 2018

Abstract
The phase shifting action of low temperature pulses of 6 °C and 2 h duration administered to the various phases of the Drosophila pseudoobscura circadian rhythm and the action of light pulses given 30 min after the beginning of these low temperature pulses have been investigated. The phase response curve obtained from experiments with light pulses during low temperature cannot be ex­ plained on the basis of a straightforward and sequential phase shifting of the oscillation by the various transitions in the pulses. The response curve, after the slight phase shifting action of the temperature pulses is corrected for, resembles the standard phase response curve 4 for light pulses (at 20 °C) in its wave form but not in its time course. Our curve is shifted in time in a manner that indicates that the light pulses accompanying the low temperature pulses arrived at phase points 1.5 h later than the actual phases at which they were given. We attribute this delay to a slowing down of the information that is apparently transmitted by a process that is temperature dependent.
Poncimarin, a New Coumarin from Poncirus trifoliata L.
Authors: Guiotto A. , Rodighiero P. , Quintily U. 
Published: August 2018

Abstract
A new coumarinic derivative (Poncimarin; C19H22O5; m.p. 140 °C) was isolated from unripe fruits of Poncirus trifoliata L. which from spectroscopic evidences was formulated as 7-(2,3-epoxy-3-methyl butyloxy)-8-(2,3-epoxy-3-me-thyl butyl) coumarin.
Bariumanreicherung in den Müllerschen Körperchen der Loxodidae (Ciliata, Holotricha) / Accumulation of Barium in Müller's Bodies of the Loxodidae (Ciliata, Holotricha)
Authors: Hubert G. , Rieder N. , Schmitt G. , Send W. 
Published: August 2018

Abstract
It is shown by energy-dispersive x-ray analysis that the Müller’s bodies of Loxodidae consist of BaSO4. Therefore statocyst function can be assumed for these bodies. The route of biosyntheses is not yet investigated.
Over-Production of Porphyrins and Heme in Heterotrophic Bacteria
Authors: Philipp-Dormston W. K. , Doss M. 
Published: August 2018

Abstract
In Escherichia coli, Pseudomonas aeruginosa, and A chromobacter metalcaligenes δ-aminolevulinic acid synthase and δ-aminolevulinic acid dehydratase appear to be the rate limiting enzymes of porphyrin and hemebiosynthesis. Bypassing of these enzymes by addition of 6-aminolevulinic acid or porphobilinogen results in overproduction of tetrapyrroles.
Binding of Antibodies onto the Thylakoid Membrane I. Maximal Antibody Binding and Adsorption of Antibodies to Lipids
Authors: Radunz Alfons 
Published: August 2018

Abstract
The binding of antibodies onto the lamellar system of Antirrhinum majus was determined in dependence on the serum addition. The unspecific adsorption of serum proteins was taken into account or eliminated. The binding of antibodies as a function of the amount of serum added is seen from a saturation curve. From an antiserum obtained by hyperimmunization with stroma-freed chloroplasts, the chloroplasts bind maximally 1 gram antibodies per gram stroma-freed chloro­ plasts. From an antiserum to the proteins of the thylakoid membrane prepared in the same way an equal amount of antibodies is adsorbed. It is assumed that with this amount the surface of the lamellar system accessible to antibodies is completely covered by antibodies. For an antiserum to monogalactosyl diglyceride a maximal antibody binding of 0.16 g, for sulphoquinovosyl diglyceride 0.12 g and for phosphatidyl glycerol 0.13 g of antibodies per gram stroma-freed chloroplasts are obtained. The significance of these results with respect to the molecular surface structure of the thylakoid membrane is discussed.