bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die pCO2-/pO2-Optode: Eine neue p CO2- bzw. pO2-Meßsonde zur Messung des pCO2 oder pO2 von Gasen und Flüssigkeiten / The pCO2-/pO2-Optode: A New Probe for Measurement of pCO2 or pO2 in Fluids and Gases
Authors: Lübbers D. W. , Opitz N. 
Published: August 2018

Abstract
To measure pO2 or pCO2 in gases or fluids the fluorescence indicators pyrene butyric acid or β-methylumbelli-feron were used, which were separated from a measuring medium by a gas-permeable membrane. For p CO2 the pH changes in NaHCO3 solution were monitored by methyl-umbelliferon. Changes in its fluorescence signal, S, were measured at λ (emission) = 445 nm. Excitation was brought about by light of wavelength λ1 = 318 nm (fluorescence signal S1) , and λ2 = 357 nm (fluorescence signal S2). Drawing lg(S2/S1) against lg(pCO2-1), one obtains a straight line between a p CO2 of 10 and 70 Torr. The response time is about 3 to 4 s (90%). For pO2 , pyrene butyric acid is used (λ (excitation) = 342 nm; λ(emission) = 395 nm). A linear increase in pO2 between 0 and 300 Torr yields a linear increase in the reciprocal fluorescence signal. The response time is about 3 s (90%).
Die Crista acustica der Tettigonioidea (Orthoptera) / The Crista acustica of the Tettigonioidea (Orthoptera)
Authors: Schumacher R. 
Published: August 2018

Abstract
The number of scolopidia of the crista acustica of the Tettigonioidea is species-specific. First electron microscopic investigations of these scolopidia show that each of them is composed of 4 cells: A bipolar sense cell, an enveloping cell, a scolopale cell and a cap cell. The dendrite of the sense cell terminates in a cilium which is anchored within the dendrite with a root, which divides into numerous rootlets. There are two basal bodies at the base of the cilium. The tip of the cilium projects into the cap of the cap cell.
A Cell for Simultaneous Measurements of Optical and Electrical Properties of Black Lipid Membranes
Authors: Noll Günter G. 
Published: August 2018

Abstract
A universal cell was constructed, which allows measurements of the resistance (d. c.), capacity, optical reflectivity, and spectral absorption of blade lipid films simultaneously. These measurements reflect different properties of the films, supplementary to each other. The purpose is to eliminate differences of experimental conditions especially in recombination experiments with proteins. The cell is totally symmetric, can be completely disassembled, and the parts are exchangeable. It allows application of several methods for film production, and is held together simply by mechanical pressure, without need of any sealing agent. The inner parts are exclusively of glass and teflon. The fluid volume of the cell is 7 -15 ml and the better than 1014 Ohms.
Mixed Monomolecular Films of Chlorophyll and Cytochromes
Authors: Chin P , Brody S. S. 
Published: August 2018

Abstract
Mixed monomolecular films of cytochrome (Cyt) and chlorophyll (Chl) were spread at a nitrogen-water interface. A large interaction is observed between reduced Cyt f and Chl a in a mixed film. Oxidized Cyt f and Chl a in a mixed film show little evidence for interaction. Mixed monomolecular films of Chl a with either reduced or oxidized Cyt c appears to result in denaturation of the protein at the surface.
A light reaction is observed only in mixed films of reduced Cyt f and Chl a.
Enzymic Capacities for Chlorophyll Biosynthesis. Activation and de novo Synthesis of Enzymes
Authors: Schneider Hansjörg A. W. 
Published: August 2018

A previously published working model for the regulation of chlorophyll formation has been tested studying early steps of chlorophyll and porphyrin biosynthesis in developing cotyledons of Helianthus annuus. The activities of δ-aminolevulinate synthetase (ALAS), δ-aminolevulinate dehydratase (ALAD), and the porphobilinogenase complex (PBGase) at any given time have been found to be strongly associated with endogenous developmental processes. Highest activities in dark­ness have been observed at times when maximum chlorophyll formation would have occurred had the plants been exposed to light. Only in the case of ALAS was the maximum activity in light much greater than that observed in the dark.
Density labeling experiments and other data suggest that enzyme synthesis is mediated both by development and by illumination. Moreover, ALAS activity appears to be subject to inhibition, presumably by products of the porphyrin biosynthesis, as indicated by halflife experiments. Rapid enzyme degradation in the absence of light seems to be less probable. Slight ALAS activity in darkness is present as long as the plastids are not fully developed.
In contrast to findings with cell cultures of tobacco, in Helianthus cotyledons ALAS certainly plays the main role in the regulation of chlorophyll biosynthesis. Nevertheless, increasing activities of the succeeding enzymes, located in the plastids, ensure that increased concentrations of δ-aminolevulinate (ALA) are drawn into the chlorophyll biosynthetic pathway. The experiments corroborate the suggestion that chlorophyll biosynthesis is controlled by different but interdependent mechanisms. The dominant regulatory mechanism is dependent on the stage of development.
Ultrastructural Changes in in vitro Ageing Spinach Chloroplasts
Authors: Kulandaivelu G. , Hall D. O . 
Published: August 2018

Abstract
Ultrastructural changes in in vitro ageing spinach chloroplasts have been studied in detail. Prolonged storage caused swelling of the chloroplasts due to the increase in the thickness and spacing of the thylakoid membranes. The increase in the thickness of the membrane is partly accompanied by the release of lipids. Addition of crystalline bovine serum albumin was found to stabilize the membrane structures. Storage of the chloroplasts at 77 °K even though it resulted in complete breakage of the whole chloroplasts, maintained the thylakoid structures in a highly intact form.
Variations in Melanin and Riboflavin Content of Amphibian Liver under the Influence of Reserpine and Amphetamine
Authors: Kokolis Nikos 
Published: August 2018

Abstract
By means of paper chromatography, Lactobacillus casei test and the staining method with the Feulgen reaction, the effects of reserpine and amphetamine on riboflavin and melanin were studied in the liver of Triturus cristatus. It was demonstrated that the concentrations of both melanin and riboflavin can be altered by the influence of these drugs. From the results obtained it is suggested that riboflavin shows a correlation with the density of melanin.
Initiation in einem Polyribosomen-abhängigen Protein-synthetisierenden zellfreien System aus Saccharomyces / Initiation in a Polyribosome-Dependent Protein-Synthesizing Cell-Free System from Saccharomyces
Authors: Schulz-Harder Bernd , Lochmann Ernst-Randolf 
Published: August 2018

Abstract
A method to prepare polyribosomes from yeasts by using the french-press is described. The highest yield of polyribosomes was derived from late log-phase cells. These polyribosomes, incubated in a cell-free system, were able to reinitiate protein synthesis, which was shown by inhibiting aminoacid incorporation by aurintricarboxylic acid, edeine and sodiumfluoride. We developed the translational system in order to look for the optimal ion-conditions of a DNA-dependent protein-synthesizing system. We found out that at the optimal MgCL2-concentration (6 mᴍ) protein synthesis was strongly inhibited by Mangan ions which are required for transcription in yeast. If protein-synthesis was carried out with 2 mᴍ and 3 mᴍ MgCl2 maximal aminoacid incorporation was observed at 2 mᴍ and 1.5 mᴍ MnCl2.
Notizen: „Synthetische“ Aiptasia mutabilis RAPP (Coelenterata) / „Synthetical“ Aiptasia mutabilis RAPP (Coelenterata)
Authors: Czygan Franz-C. 
Published: August 2018

Abstract
After being cultivated in the dark for some months and after being fed with food free of carotenoids during the time Aiptasia mutabilis (Coelenterata) loses its symbiontic algae (rich in brown fucoxanthin) and becomes transparent white. This disarranged symbiosis may be regenerated under light cultivation by adding different species of Chlorophyceae (Chlorella, Dunaliella) and Chrysophyceae (Ochromonas, Cyclotella), but not of Cyanophyceae (Anabaena, Nostoc, Oscillatoria, Anacystis). - This changeable life system between coelenterata and algae may be a good example for further studies of the endosymbiosis problem.
Notizen: Isosativan: an Isoflavan Phytoalexin from Trifolium hybridum and other Trifolium Species
Authors: Ingham John 
Published: August 2018

Abstract
An isoflavonoid phytoalexin isolated from the fungusinfected leaves of Trijolium hybridum has been identified as 7,4′-dimethoxy-2′-hydroxyisoflavan.
Notizen: The Dorsal Eye of Cloeon dipterum (Ephemeroplera) (A Light- and Electronm icroscopical Study)
Authors: Wolburg-Buchholz Karen 
Published: August 2018

Abstract
The superposition eye of Cloeon dipterum is a clear zone type of compound eye. The central ommatidia have two rhabdomes, at different levels, a small apical and a main basal one. The number of basal rhabdomes is greater than the number of dioptric apparatuses. This and the role of the retinula cell processes is discussed with regard to super­ position or light-guide theory.
Notizen: Valine-Induced Inhibition of Growth of Haploid Tobacco Protoplasts and Its Reversal by Isoleucine
Authors: Bourgin Jean-Pierre 
Published: August 2018

Abstract
Valine-Isoleucine Interaction, Tobacco Protoplasts ʟ-valine inhibits the division of haploid tobacco mesophyll protoplasts. This inhibition is reversed by simultaneous addition of ʟ-isoleucine to the culture medium.
1H and 13C NMR Study of Proton Transfer in Azoles. Mechanism of Proton Transfer in Pyrazole in Solutions Containing bis-(Acetylacetonato) Nickel (II)
Authors: Babin V. N. , Zavelovidi E. B. , Fedin E. I. 
Published: August 2018

Abstract
Proton Transfer, Pyrazole, Outer-Sphere Coordination Proton transfer in pyrazole systems involving interaction with a paramagnetic transition metal complex has been studied with 1H and 13C NMR techniques. Kinetics of the ligand exchange in the pyrazole complex of bis-(acetylacetonato) nickel (II) has been investigated, and hyperfine coupling constants for the interaction of the nickel unpaired electron with the ligand nuclei in the complex have been determined. Catalytic admixtures of bis-(acetylacetonato) nickel (II) are shown to modify the mechanism of the proton transfer in pyrazole. The spectral data are discussed in terms of outer-sphere coordination and cooperative proton transfer effects.
MO Calculations of Some Thymine Radicals at the INDO Level
Authors: Westhof E , Van Rooten M 
Published: August 2018

Abstract
The results of MO INDO calculations of some thymine radicals are presented. These include as well as the hydrogen addition radicals the hydroxyl addition radicals to C5 and to C6 of the C5=C6 double bond of the thymine molecule. The radicals resulting from hydrogen abstraction from the methyl group and from the nitrogen N1 are also studied. Except for radicals where the main spin density is localized on nitrogen atoms, the agreement between experimental and theoretical couplings is satisfactory.
Sesquiterpene Hydrocarbons of the Liverwort, Dumortiera hirsuta
Authors: Matsuo Akihiko , Uto Seiryû , Nakayama Mitsuru , Hayashi Shûichi 
Published: August 2018

Abstract
Sesquiterpene hydrocarbons of the hexane extract from Dumortiera hirsuta were analyzed by a combining method of gas chromatography and mass spectrometry, and ten sesquiterpene hydrocarbons, (δ-elemene, α-copaene, β-bourbonene, β-elemene, γ-elemene, β-pompene, γ-muurolene, α-muurolene, bazzanene and cuparene, were identified.
Localization of the Tri-and Digalactosyl Diglyceride in the Thylakoid Membrane with Serological Methods
Authors: Radunz Alfons 
Published: August 2018

Abstract
Trigalactosyl diglyceride was isolated from leaves of Urtica dioica and characterized by thin layer chromatography, infrared spectroscopy and by its fatty acid composition. An antiserum to the trigalactolipid was obtained by immunization of rabbits. By means of inhibition experiments with oligosaccharides and mono-and digalactosyl glycerol it was demonstrated that the antibodies are directed towards the α-galactosyl-(1 → 6) -α-galactosyl-(1 → 6) -β-galactosyl-(1 → 1) -glycerol con­figuration of the trigalactosyl diglyceride. Monogalactosyl diglyceride and sulfoquinovosyl diglyce­ ride do not react with this antiserum. However, a cross reaction was observed with digalactosyl diglyceride. The presence of antibodies to tri-and digalactosyl diglyceride was demonstrated in antisera to different chloroplast preparations of Antirrhinum majus and Spinacia oleracea.
The antiserum to the trigalactolipid agglutinates stroma-freed chloroplasts. Membrane fragments obtained by the ultra sonication were precipitated. The antiserum is exhausted by trigalactosyl di­glyceride but not by digalactosyl diglyceride or digalactosyl glycerol. The antiserum treated with digalactosyl glycerol and digalactosyl diglyceride also agglutinated stroma-freed chloroplasts. 1 g stroma-freed chloroplasts binds 0.17 g antibodies to trigalactolipid. Membrane fragments bind more antibodies to trigalactolipids than stroma-freed chloroplasts. From the agglutination tests it follows that the antigenic determinants of the trigalactolipid and the digalactolipid are localized in the outer surface as well as in the surface directed towards the inside of the thylakoid membrane.
Studies on Mammalian Pheromones, II. Further Compounds from the Pedal Gland of the Bontebok ( Damaliscus dorcas dorcas)
Authors: Burger B. V. , Roux Maritha le , Garbers C. F. , Bigalke R.C. , Pachler K.G.R. , Wessels P.L. , Christ V. , Maurer K. H. 
Published: August 2018

Abstract
The identification of four further major constituents of the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. α-terpineol, 2-n-heptylpyridine, m-cresol and (Z)-6-dodecen-4-olide and the investigation of the stereochemistry of the double bond in (Z) -6-dodecen-4-olide by means of iterative computer analysis are described. An improved synthesis of this compound is outlined.
Analytische Untersuchungen des Wehrsekretes von Peripatopsis moseleyi (Onychophora) / Analytical Investigations of the Defensive Secretion from Peripatopsis moseleyi (Onychophora)
Authors: Röper Harald 
Published: August 2018

The defensive secretion of Peripatopsis moseleyi (Onychophora) consists of 84% water and 16% protein and free amino acids. The secretion’s defensive effectiveness is an anti-predator “sticking” action. The secretion is flung out of the oral papillae in liquid state. It is then denaturized by the air and develops increasingly sticky white threads, probably through the devel­opment of disulfide bridges from the protein content.
The elastic properties of the secretion threads indicate a micellar structure. The defensive secretion contains no volatile organic components or carbohydrates. This was confirmed by gas- liquid chromatography and thin-layer chromatography.
After acidic hydrolysis of the secretion the following amino acids were determined quantita­tively: aspartic acid, threonine, serine, proline, glutamic acid, glycine, alanine, valine, cysteine, methionine, isoleucine, leucine, tyrosine, phenylalanine, lysine, histidine and arginine. A “rare” amino acid was not identified. Tryptophane was not present (basic secretion hydrolysis). The quantita­tive determination of free amino acids, based on the total content, showed the following results: glycine (40.9%), glutamic acid (10.8%), aspartic acid (2.65%), lysine (1.3%).
This result shows, that the secretion is stored in a watery glycine/glutaminic acid buffer in the oral papillae of Peripatopsis moseleyi.
High voltage paper electrophoreses and gel filtration experiments with dextran and agarose gels showed, that the secretion protein consists of, at least, two fractions with different molecular weight.
Inhibition of Photosystem II-Reactions in Blue-Green Algae by the Antisera to Lutein and Neoxanthin
Authors: Schmid Georg H. , List Helga , Radunz Alfons 
Published: August 2018

An antiserum to lutein agglutinates thylakoids of Nostoc muscorum and Oscillatoria chalybea. From this it follows that lutein is located in the outer surface of the thylakoid membrane of these blue-green algae. The same result is obtained for an antiserum to neoxanthin. As neoxanthin is supposed not to occur in blue-green algae it follows that in this case the antibody action should be directed towards a carotenoid with allenic structure. The antisera to lutein and neoxanthin inhibit in both investigated algal species photosynthetic electron transport on the oxygen-evolving side of photosystem II. Moreover, the inhibition sites of both antisera are identical in Nostoc muscorum and are located between the sites of electron donation of the artificial electron donors tetramethyl benzidene and diphenylcarbazide. In the case of the blue-green alga Oscillatoria chalybea the inhibition sites of both antisera differ. Whereas the inhibition site of the antiserum to neoxanthin lies again between the sites of electron donation of tetramethyl benzidine and di­phenylcarbazide, the inhibition site of the antiserum to lutein appears to be situated at least partially beyond the site of electron donation of tetramethyl benzidine.
The degree of inhibition of electron transport reactions with Nostoc muscorum is for both antisera 50 - 60 per cent and is pH-dependent. The pH-optimum lies at pH 7.2 for the antiserum to neoxanthin and at 7.8 for the antiserum to lutein.
In comparison to this data the same antisera inhibit electron transport in chloroplasts from higher plants only by 20%. This low degree of inhibition in higher plants is apparently due to the fact that the surfaces of the thylakoids are not accessible to antibodies within the grana. In contrast to this the thylakoid surfaces of blue-green algae are fully accessible because the thylakoids are unstacked.
The thylakoids of Oscillatoria chalybea have the tendency towards aggregation. Therefore, the results concerning the accessibility of the carotenoids to antibodies are not so clear cut as with Nostoc muscorum.
Multiple Effects of Amobarbital on Ehrlich Ascites Tumor Cells. Inhibition of Pyruvate Dehydrogenase
Authors: Postius Stefan , Schneider Friedhelm 
Published: August 2018

Abstract
The inhibition of the proliferation of hyperdiploid Ehrlich ascites tumor cells in suspension cultures by amobarbital is coupled to an increased glycolytic activity as shown by lactic acid pro­ duction and glucose consumption; higher concentrations of amobarbital than 1 mᴍ enhance the ATP/ADP ratio of the total cell. The actual activity of pyruvate dehydrogenase of intact cells is completely inhibited in the presence of 2 mᴍ amobarbital as was shown by the 14CO2 evolution from [1-14C] pyruvate or the incorporation of 14CO2 into the total lipid fraction of the cells from [U-14C] pyruvate or from [U-14C] lactate. The pyruvate dehydrogenase complex from Ehrlich ascites tumor cells is completely inhibited by 1 mᴍ amobarbital in vitro. The activity of α-oxoglutarate dehydrogenase is inhibited by amobarbital, too, as was shown by measuring the 14CO2 evolution from [1-14C] glutamate with intact cells.
It is suggested that the inhibition of pyruvate dehydrogenase in the presence of amobarbital is the result of a direct action on the enzyme as well as the consequence of a change in the cellular redox state or its energy charge.
99.26 per cent Water Content in the Fresh-water Medusa Craspedacusta sowerbii
Authors: Ludwig Herbert W. 
Published: August 2018

Abstract
The fresh-water medusa Craspedacusta sowerbii (Hydrozoa: Limnomedusae) contains 99.26% water, 0.67% organic matter, and 0.07% inorganic materials. Its cation concentrations are compared to those of Aurelia aurita, sea-water, and habitat water.
Determination of the Liquid Scintillation Counting Efficiency of 3H and/or 14C Labelled Samples Independently of the Degree of Colour and/or Chemical Quenching
Authors: Atallah Khaled , Rauschenbach Peter , Simon Helmut , Berthold Fritz , Kolbe Wolfgang 
Published: August 2018

Abstract
A value R is obtained by the ratio of the summed, coincident pulses of both photomultipliers to the coincident pulses of one photomultiplier in the same selected range of the external standard puls height spectrum. This value R together with the external standard channel ratio (ESCR) show the extent of chemical and/or colour quenching in a field described by a set of calibration samples with increasing chemical or colour quenching (Fig. 3). The counting efficiency of samples with different and unknown proportion of chemical and/or colour quenching can be determined much more accurate than by any calibration approach using the ESCR only (Table VI). The method can be used for 3H samples with a counting efficiency ≧10% and 14C samples of ≧5%, respectively. The new correction procedure is also applicable for 3H and 14C double-labelled compounds.
The Solubility of Insect Juvenile Hormone in Aqueous Solutions and Its Adsorption by Glassware and Plastics
Authors: Giese Ch. , Spindler K. D. , Emmerich H. 
Published: August 2018

Abstract
The C18 juvenile hormone of insects can be dissolved in aqueous solutions up to a concentration of 2.5 - 3.0 × 10-5 M; changes in pH, buffer composition and ionic strength hardly affect this solu­bility. The hormone is salted out gradually by increasing ammonium sulphate concentrations. The juvenile hormone is bound to proteins such as bovine serum albumin or goat immunoglobulin G and can be kept in solution by these proteins up to 10-3 M. The hormone is strongly absorbed by many commonly used plastic materials but only to a lesser extent by glass and teflon.
Schwermetalle in höheren Pilzen Cadmium, Zink und Kupfer Heavy Metals in Higher Fungi Cadmium, Zinc, and Copper
Authors: Meisch Hans-Ulrich , Schmitt Johannes A. , Reinle Wolfgang 
Published: August 2018

Abstract
In a series of 190 samples, higher fungi, especially from the genus Agaricus, were analyzed by atomic absorption spectroscopy on their content of the trace metals cadmium, zinc, and copper. Cd was found to be present in high concentrations in some Agaricus species belonging to special taxonomic groups. In relation to soil concentrations, Cd is highly enriched in some Agaricus spec., the enrichment being a taxonomic criterion of special value. Among the remaining genera of higher fungi, only Leucoagaricus and Amanita showed similiar enrichment properties for cadmium. The chemically related metals Zn and Cu were found to be relative uniformely distributed in all analyzed fungi. No synergistic or antagonistic relationship between Cd and the other two metals could be detected in the mushrooms.
Activation of Chromatin-Bound DNA-Dependent RNA Polymerase (E.C. 2.7.7.6.) in Plant Storage Tissue Slices
Authors: Kahl Günter , Wechselberger Manfred 
Published: August 2018

Abstract
Chromatin, RNA Polymerase, Potato Tuber Tissue, Aging Phenomenon The synthesis of RNA by chromatin-bound RNA polymerase (E.C. 2.7.7.6.) from white potato tubers proceeds at a low rate, which is enhanced after slicing the tissue, however. Concomitantly DNA template availability as measured with saturating amounts of Escherichia coli polymerase is diminished drastically. Nearest neighbor frequency analysis proved that the RNA synthesized on chromatin of intact tubers is different from that synthesized on chromatin of sliced tissue.
The RNA polymerase of white potato tubers is dependent on all four ribonucleoside triphos­ phates and a divalent metal ion such as Mg2+ or Mn2+ and totally inhibited by the presence of pyrophosphate. Actinomycin D blocks the formation of the RNA product, which could be shown to be a heteropolymer by nearest neighbour frequency technique. The Km of the chromatin-bound enzyme with regard to ATP, GTP, CTP and UTP was 5.1 X10-5 M, 1.6X10-5 M, 0.9X10-5 M and 0.45 X 10-5
M/1 respectively, α-amanitin inhibits the overall activity to about 50%, which indicates the presence of equal amounts of polymerase I and polymerase If.