bluuebunny/crossref_metadata_2025 huggingface dataset:
Świat kolorów ludzi paleolitu jako element intertekstualności „obrazów” w jaskiniach
Authors: Minta-Tworzowska Danuta
Published: July 2018

The article discusses an issue of intertextuality of “pictures” in Palaeolithic art, and colour as its constituent. An important concept in these regards appeared to be that of an open and interdisciplinary approach towards an image, derived from the anthropology of images. In my opinion, essential is an “acting” of an image, based on so called “interimaginal relations”. It is legitimate when referring to prehistory, as numerous images reveal interpenetrating traces of other representations. Either consciously or unconsciously, some solutions had been used repeatedly, copying other representations, including selection of colours as a kind of stereotype deeply rooted in cultural memory. In cave “pictures” there were one or two main colours used, rarely three or even four. It has been acknowledged that the most important features of Palaeolithic “pictures” were movement, colour, especially expressed by a contrast of black and red or yellow, and also an illusion. They were also interrelated with a sound. The world of colours of contemporary people was a significant constituent of cultural meanings and of images “acting” in “mediatisation” of important existential contents between past and present.
Weryfikacja śladów użytkowania kościanych szydeł i stilusów – studium eksperymentalne
Authors: Stelmasiak Monika
Published: July 2018

Awls have been used for perforating various types of materials from the Paleolithic to the early medieval period, until they were replaced by their metal equivalents. Though the technology of the manufacture has changed, the form remained virtually the same, containing of a handle and a shaft. Stiluses are the component of the stationery set, which also consists of the wax tablets. The latter however, very rarely preserve to our times. Bone awls and stiluses are as well the common type of relics found on the early medieval sites. Recent studies were mainly oriented on their chronological and typological classification and on determining the place of their manufacture and the place of their use. Yet, there were no attempts of conducting a use wear analysis, which leads to the appropriate characteristic of these tools, previously obtained in a very generic way, mostly basing on their morphological features which is quite misleading, due to their overall similarity. That was an impulse to undertake research on that field. Conducted experiments and use-wear analysis resulted in obtaining an accessible way to distinguish bone awls from bone stiluses, which enabled authoress to apply this method on genuine artifacts from early medieval sites.
Über die Kristallstruktur von KSc2 F7 / The Crystal Structure of KSc2 F7
Authors: Güde Klaus , Hebecker Christoph
Published: August 2018

Single crystals of KSc2F7 have been prepared from a mixture of KF and ScF3 . The samples were investigated by X-ray methods. KSc2F7 crystallizes orthorhombically with a = 10.643(2), b = 6.540(1), c = 4.030(1) Å. These data indicate a close crystallographic connection to the monoclinic unit cell of KIn2F7 [1], But in contrast to KIn2F7 , KSc2 F7 crystallizes in space group No. 65. Cmmm - D19
2h. The R-value for 341 observed independent reflections is 0.060.
Kristall- und Molekülstruktur von 2-[3-(N,N-Diethylammonium)propylimino]-2-phenyl-dithioacetat / Crystal and Molecular Structure of 2-[3-(N,N-Diethylammonium)propylimino]-2-phenyl-dithioacetate
Authors: Heinemann Frank W. , Hartung Helmut , Maier Nadja
Published: August 2018

The title compound, formed by the reaction of acetophenone with 3-diethylamino-1-propylamine and sulfur, crystallizes in the orthorhombic space group P212121 (Z = 4) with lattice constants a = 818.1(2) pm, b = 1225.1(2) pm and c = 1622.4(4) pm. The characterization of the molecule as a zwitterion is established by the observed bond parameters. Both spectroscopic investigations and the results of the X-ray structure determination show that a hydrogen atom is bonded to the amino nitrogen rather than to the imino nitrogen.
Carbon Supported Pt+Os Catalysts for Methanol Oxidation
Authors: Gökağaç Gülsün , Kennedy Brendan J.
Published: August 2018

11% Pt/C, 10% Pt + 1%Os/C, 9% Pt + 2%Os/C, 8% Pt + 3%Os/C, 7% Pt + 4%Os/C, 6% Pt + 5%Os/C and 5%Pt + 6% Os/C catalysts have been prepared for methanol oxidation reaction. Transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cyclic voltammetry have been used to understand the nature of the species present in these catalysts. 7% Pt + 4% Os/C was the most active catalyst, while 8% Pt + 3% Os/C was the least active one. It is found that the metal particle size and distribution on the carbon support, the surface composition and the oxidation states of the metal particles, the metal-metal and metal support interactions are important parameters to define the activity of the catalyst.
Cationic Ruthenium-Sulfine Complexes: Synthesis and Dynamic Behaviour
Authors: Kuhnert Nikolai , Burzlaff Nicolai , Dombrowski Eberhard , Schenk Wolfdieter A.
Published: August 2018

Cationic ruthenium sulfine complexes [CpRu(PR´3)2(O=S=CHR)]PF6 have been obtained by a variety of methods. Oxidation of the thioaldehyde complexes [CpRu(PR´3)2(S=CHR)]PF6 with either 2-tosyl-3-phenyl-oxaziridine (PR´3 = PMe3 ) or magnesium-monoperoxyphthalate (PR´3 = 1/2 dppm) gave complexes of arylsulfines (R = Ph, 3-C6H4F, 4-C6H4Cl, 4- C6H4OMe) selectively in their thermodynamically less stable E form. Siloxane elimination from the sulfinato complexes [CpRu(PMe3)2(SO2CHRSiMe3)] yielded complexes of aliphatic sulfines, [CpRu(PMe3)2(O=S=CHR)]PF6 (R =H,Me). Treatment of [CpRu(dppm)(SO2CH2R)] with acetyl chloride led to an oxygen redistribution giving complexes of thioaldehydes [CpRu(dppm)(η2-S=CH2)]PF6 and [CpRu(dppm)(η1-S=CHR)]PF6 (R = Ph, 4-C6H4Cl). The structure of the latter was determined by X-ray crystallography. The loss of oxygen can be suppressed by performing the acylation-elimination sequence in the presence of poly-(4-vinylpyridine). This provided a selective access to complexes of Z-sulfines, [CpRu(PMe3)2(O=S=CHR)]PF6 (R = Ph, 4-C6H4Cl) and [CpRu(dppm)(O=S=CHR)]PF6 (R = Ph, 4-C6H4Cl, COOEt, Cl). Complexes of the parent sulfine O=S=CH2 were also obtained by SO transfer to the methylene complex [CpRu(PMe3)2(CH2)]PF6 and methylene transfer to the sulfur monoxide complex [Cp*Ru(PMe3)2 (SO)]PF6. Most of the new sulfine complexes exhibit dynamic behaviour in solution, i. e. ligand rotation, ligand inversion, and η2 /η1 hapticity change. O-Alkylation provided the dicationic complex [CpRu(PMe3)2 (EtO-S=CHMe)](PF6)2, and S-oxidation gave the sulfene complexes [(C5R5)Ru(PMe3)2 (O2S=CH2)]PF6 (R = H, Me).
Isolation and Structure Elucidation of Two New Xanthones from Gentiana azurium Bunge (Fam. Gentianaceae)
Authors: Purev O. , Oyun Kh. , Odontuya G. , Tankhaeva A. M. , Nikolaeva G. G. , Khan Khalid M. , Ali Shah Syed Tasadaque , Voelter Wolfgang
Published: August 2018

Two new natural xanthones, 1,3,5-trihydroxy-8-methoxyxanthone (1) and 3,5-dihydroxy-8- methoxy-1-O-β-D-glucopyranosyl xanthone (2) were isolated along with two known xanthones from Gentiana azurium Bunge (Fam. Gentianaceae). Their structures were determined on the basis of their spectral data.
Linearly Fused Furochromones by Intramolecular Enaminone Reactions
Authors: Abdel-Rahmana Abdel-Rahman H. , Keshk Eman M. , El-Telbani Emad M.
Published: August 2018

A number of new linearly fused furochromones were synthesized. The methodology was performed starting from naturally occurring visnagin and khellin via enaminone formation using N,N-dimethyl formamide dimethylacetal followed by ring closure in acidic medium. Various reactions on the enaminone derivatives are described.
A Hydrogen Bonded Aluminium Alkoxide Hydroxide Aggregate Resulting from the Exposure of Methylaluminium Dichloride to Air
Authors: Mitzel Norbert W. , Lustig Christian
Published: August 2018

Exposure of methylaluminium dichloride to air results in the formation of a crystalline hydrolysis/ oxidation product of the composition [(MeOAlCl2)3][(MeOAlCl2)2(HOAlCl2)], which is linked by a H···Cl hydrogen bond in the solid state. Oxygen is thus inserted into the carbon-aluminium bond in the primary reaction, whereas hydrolysis plays only a minor role.
Molecular Complexes, 14. Isomeric Arene Complexes of Caffeine and 1,3,7,9-Tetramethyluric Acid Detected with Toluene. Polar Interactions Inverted with Hexafluorobenzene
Authors: Stamm Helmut , Jäkel Hannelore , Stafe Jügen
Published: August 2018

Stacking of an arene D on caffeine (1) near 7-Me and 8-H is known (1H NMR shifts, CCl4, AUS concept) to yield the same association constant K for each signal of 1. Toluene (T) and 1 now yielded the same K from 7-Me and 8-H while K from 1-Me (and 3-Me) is smaller indicating a minor stacking centre near N-1 that forms both 1T and 1T2; this 1T2 disturbs computations of K. The main stacking centre forms no 1T2 since its 1T is stabilized by dipole-dipole interaction. Diphenylmethane Dp, a substituted T that cannot form a dimer of type T2, does not form 1Dp2. Ethyl of 1-ethyltheobromine (2) is proven to stand perpendicular so that the above minor complex can only arise on one face of 2 halving Kminor and making the disturbance of computations by 2T2 insignificant; apart from this minor 2T there are cis-trans isomers of the main complex. Stacking of 1 and 2 with larger arenes is discussed in terms of relative molecular sizes under consideration of the perpendicularly placed ethyl group of 2. Stacking of D near N-3 and N-9 of 1,3,7,9-tetramethyluric acid (4) is known. 4 and T now provided K = 0.218 l mol−1 from 3-Me and 9-Me but K = 0.157 l mol−1 from 1-Me and 7-Me. This and the complex induced shifts IK indicate formation of stacking 4T + 4T2 and of two edge-on 4T standing on 3-Me and 9-Me under dipole-dipole interaction with a neighbouring oxygen. The oxygens of 4 (and probably of 1, too) form edge-on complexes with hexafluorobenzene; this underlines the importance of polar effects.
Synthesis and Tin(IV) Coordination Chemistry of the Novel Tripod N(CH2CH2CH2SH)3
Authors: Hahn F. Ekkehardt , Dittler-Klingemann Andreas , Lügger Thomas
Published: August 2018

The novel tetradentate ligand N(CH2CH2CH2SH)3, H3 - 5 was synthesized from tripropanolamine via the trichloride, subsequent reaction with potassium thioacetate and reduction with LiAlH4. Ligand H3 -5 reacts with MeSnCl3 under formation of the centrosymmetric dinuclear complex [MeSn(5)]2, 6, which was shown by X-ray structure analysis to contain two tetrahedrally coordinated tin atoms and two bridging thiolato functions.
Density Functional Theory (DFT) Calculations of Indirect Nuclear Spin-Spin Coupling Constants 1J(31P, 13C) in λ3-Phosphaalkynes
Authors: Wrackmeyer Bernd
Published: August 2018

The calculation of the spin-spin coupling constants 1J(31P,≡13C) of λ3-1-phosphaalkynes P≡C-R (R = H, Me, tBu, Ph, SiMe3 and NMe2) using density functional theory (DFT) have revealed a positive sign of this coupling constant in agreement with the experiment for P≡C-tBu. The calculations have shown that the Fermi contact (FC) contribution to this coupling is negative [in contrast to FC for 1J(14N,≡13C) in the corresponding nitriles], and that the positive sign of 1J(31P,≡13C) is the result of significant contributions arising from spin-dipole (SD) and paramagnetic spin-orbital (PSO) terms. Coupling constants were also calculated for some representative λ3-phosphorus compounds containing two- and three-coordinate phosphorus, indicating the strong dependence of the FC term on the geometry at the phosphorus atom.
Layered Double Hydroxides as Supports for Norbornene Addition Polymerisation Catalysts
Authors: Grafova Iryna A. , Grafov Andrei V. , Costantino Umberto , Marmottini Fabio , Dias Marcos L.
Published: August 2018

Addition polymerisation of norbornene with transition metal catalysts activated by methylaluminoxane was first realised on heterogeneous catalytic systems. Advanced inorganic functional polymers possessing anion-exchange properties - layered double hydroxides of Al and Zn of hydrotalcitetype - were applied as supports. They possess high polarity and are selective towards polar molecules like organometallic compounds. The activity of immobilised nickel catalysts was found to be higher than that of the homogeneous one. A certain catalytic activity was also found for group 4 phthalocyanines. The polynorbornenes obtained were characterised by gel permeation chromatography and SEM microimaging. The support’s morphology influences the shape, density, and dimensions of the resulting polymer particles.
Diastereoselectivity in the Synthesis of Unnatural α-Amino Acid Esters by Phase Transfer Catalysis
Authors: Lins Francisco Furtado Tavares , da Cunha Lázaro Pereira , Pouliquen Yvone Brígido Memória , Lemos Telma Leda Gomes , de Mattos Marcos Carlos
Published: August 2018

Two unnatural α-amino acid esters were prepared in good yields via phase transfer catalyzed Michael addition of ethyl N-acetylaminocyanoacetate to chalcone and benzalketone. For both α- enones, a progressive increase in product diastereomeric excess (d.e.) was observed during the course of reaction, even in the absence of quaternary ammonium salt. However, for a fixed reaction time, higher d.e. values were obtained under phase transfer catalytic condition. Analogous reactions were performed using S-aryl thiocinnamates as Michael acceptors, affording a 2-pyrrolidinone in good yield but low d.e. These results were interpreted on the basis of the reversibility of the Michael reaction
Crystal Structure and Magnetic Properties of a Novel CuIINdIII Heterodinuclear Schiff Base Complex
Authors: Elmali Ayhan , Elerman Yalçın
Published: August 2018

The crystal structure of L’Cu(Me2CO)Nd(NO3)3 (L’ = N,N’-bis(2-hydroxy-3-methoxybenzylidene)- ethylenediamine) was determined and the magnetic properties of the complex were investigated. (C18H18N2O4)Cu(C3H6O)Nd(NO3)3, monoclinic, space group P21/c, with a = 9.8792(9), b = 18.904(4), c = 15.667(2) Å , β = 95.360(10)°, V = 2913.1(8) Å3, Z = 4. The central region of the complex is occupied by CuII and NdIII ions which are bridged by two phenolato oxygen atoms of the ligand. The copper ion adopts a square-based 4+1 coordination made, the basal N2O2 donors being afforded by the ligand while the axial position is occupied by the oxygen atom of the acetone molecule. The NdIII ion is deca-coordinated. In addition to the two phenolate oxygen atoms, the coordination sphere contains two oxygen atoms of the OMe side arms of L and six oxygen atoms from the three bidentate nitrate ions. The Cu···Nd separation is 3.466(2) Å . The χT versus T plots, χ being the molar magnetic susceptibility per CuIINdIII unit and T the temperature, has been measured in the 4.5 - 299.6 K temperature range. The magnetic properties of the investigated compound are dominated by the crystal field effect on the NdIII site, masking the magnetic interaction between the paramagnetic centers.
Synthesis and Characterization of Cl2HSi-O-NMe2
Authors: Vojinović Krunoslav , Mitzel Norbert W. , Foerster Thomas , Rankin W. H.
Published: August 2018

O-(Dichlorosilyl)-N,N-dimethylhydroxylamine, Cl2HSiONMe2, was synthesised by the reaction of O-lithio-N,N-dimethylhydroxylamine with an excess of trichlorosilane. The compound was characterised by multinuclear NMR spectroscopy (1H, 13C, 15N, 29Si), gas-phase IR spectroscopy and mass spectrometry. The structure of Cl2HSiONMe2 was determined by gas-phase electron diffraction. It exists as two conformers in the vapour, named anti and gauche after the position of the SiH hydrogen atom relative to the SiON skeleton. The anti:gauche ratio in the vapour was determined to be 40:60. The anti conformer shows only a weak attractive interaction between the geminal donor and acceptor centres N and Si [angle Si-O-N 111.1(20)­°], whereas these interactions are stronger in the gauche conformer [angle Si-O-N 98.8(12)°]. Further structure-determining forces from weak hydrogen bridges of the Si-Cl ···H-C type and van der Waals repulsive forces are also discussed. The experimental results are in reasonable agreement with ab initio calculations at the MP2/6-311++G** level of theory.
Synthesis, Crystal Structure, and Spectroscopic and Magnetic Properties of a Dinuclear Iron(III) Complex Asymmetrically Bridged by a Phenoxo and a Methoxo Group
Authors: Zeyrek C. T. , Elmali A. , Elerman Y.
Published: August 2018

A new dinuclear iron(III) derivative Fe2L(OCH3)Cl2 (L = 1,3-bis[N-(5-chloro-2-hydroxybenzylidene)- 2-aminoethyl]-2-(5-chloro-2-hydroxyphenyl)imidazolidine) has been synthesized, it crystal structure determined and magnetically characterized. The two iron(III) ions are asymmetrically bridged by a phenoxo and a methoxo group and separated by 3.150(2)Å . The magnetic susceptibility of the complex was measured over the range 5 - 349.3 K and the observed data were successfully simulated by the equation based on the spin-Hamiltonian operator

, indicating very weak antiferromagnetic coupling between the iron ions with J = −11.3 cm−1. The magnetic and structural parameters of the compound and the nature of the magnetic super-exchange interaction are discussed and compared with data of similar dinuclear iron(III) complexes.
5,5-Diethylbarbiturate Complexes of Silver with 2,2’-Bipyridine and 3-(2-Pyridyl)propanol: Syntheses, Crystal Structures, Spectroscopic, Thermal and Antimicrobial Activity Studies August 28, 2007
Authors: Yilmaz Fatih , Yilmaz Veysel T. , Karakaya Haydar , Büyükgüngör Orhan
Published: August 2018

Two silver 5,5-diethylbarbiturate (barb) complexes with 2,2'-bipyridine (bpy) and 3-(2-pyridyl) propanol (pypr), [Ag(barb)(bpy)] (1) and [Ag(barb)(pypr)] (2), have been prepared and characterized by elemental analysis, IR spectroscopy, thermal analysis, and single crystal X-ray diffraction. Both complexes crystallize in the triclinic space group P1 with Z = 2. The barb ligand in 1 is N-coordinated and the bpy ligand acts as a bichelating ligand leading to an AgN3 tricoordination. Crystals of 1 feature a three-dimensional network based on N-H···O hydrogen bonding, π(bpy)···π(bpy), C-H···π(bpy) and π(bpy)-Ag interactions. In 2, the pypr and barb ligands behave as monodentate ligands through their N atoms, forming a distorted linear AgN2 coordination. Molecules of 2 are doubly bridged by N-H···O hydrogen bonds and further connected via O-H···O hydrogen bonds and aromatic π(pypr)···π(pypr) stacking interactions into a supramolecular network. Both complexes exhibit similar thermal decomposition behavior in air. The first stage corresponds to removal of the co-ligands such as bpy or pypr while the degradation of the barb moiety occurs at higher temperatures to give Ag2O. Like the barb, bpy and pypr ligands, 2 does not show any significant antimicrobial activity, but 1 is active against bacteria and fungi
Double-Keggin-type Anion-templated Synthesis of a 3D Porous Coordination Polymer of Eu(III) Ions and dpdo Ligands
Authors: Wei Mei Lin , Sun Rui Ping , Jiang Kai
Published: August 2018

A porous coordination polymer, {[Eu(dpdo)4(H2O)3]H(SiMo12O40)(dpdo)0.5(CH3CN)0.5(H2O)4}n (1), (where dpdo is 4,4′-bipyridine-N,N′-dioxide) templated by double-Keggin-type polyanions has been synthesized through the self-assembly of Eu(III) ions and dpdo in acetonitrile/water solution and structurally characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The X-ray structure analysis reveals that compound 1 exhibits a 3D non-interwoven framework with large cavities housing centro-symmetrically related shoulder-by-shoulder double-Keggin anions as guests. The result of a thermogravimetric analysis suggests that the metal-organic framework has high thermal stability.
Val-Geninthiocin: Structure Elucidation and MSn Fragmentation of Thiopeptide Antibiotics Produced by Streptomyces sp. RSF18
Authors: Sajid Imran , Shaaban Khaled A. , Frauendorf Holm , Hasnain Shahida , Laatscha Hartmut
Published: August 2018

Val-Geninthiocin (2), a new member of thiopeptide antibiotics, was isolated from the mycelium of Streptomyces sp. RSF18, along with the closely related geninthiocin (1) and the macrolide, chalcomycin. By intensive NMR and MS studies, Val-geninthiocin (2) was identified as desoxygeninthiocin, a thiopeptide, containing several oxazole and thiazole units and a number of unusual amino acids. Compound 2 shows potent activity against Gram-positive bacteria and minor antifungal activity, while it is not effective against Gram-negative bacteria or microalgae. Here we describe the fermentation, isolation and structure elucidation as well as the biological activity of 2.
Enzymatic Hydrolysis of Poly-ᴅʟ-Lysine
Authors: Darge W. , Sass R. , Thiemann W.
Published: August 2018

The condensation of racemic lysine to poly-ᴅʟ-lysine produces a great number of distinguishable molecules. Following merely statistical reasoning the number of “pure peptides“ - consisting of only one sort of enantiomers - should be extremely low. The hydrolysis of poly-ᴅʟ-lysine by pronase and taka-diastase shows that a content of about 3% “pure“ poly-peptide is found in the product, which emphasises the preferential sythesis of identical enantiomers within the polymer diain.
Die Epidermis von Tenebrio molitor L. Puppen als Zielorgan für das Juvenilhormonanaloge 10.11-Epoxy-6.7-trans-2.3-trans-farnesylpropenyläther / The Epidermis of the Pupae of Tenebrio molitor L. as Target Organ for the Juvenile Hormone Analogue 10,11-Epoxy-6,7-trans-2,3-trans-farnesylpropenylether
Authors: Schmialek Peter , Borowski Marina , Geyer Astrid , Miosga Verena , Nündel Michael , Rosenberg Eckhard , Zapf Burger
Published: August 2018

In vivo tests give evidence that the epidermis is the target organ for the juvenile hormone of insects. A study of the distribution of injected 10,11-epoxy-6,7-trans-2,5-trawi-farnesyl-propenylether and of its metabolic products in epidermis, lymphae, and other organs demonstrated that the unaltered ether accumulates in the epidermis against a concentration gradient and is more slowly metabolised there than in the non-target organs.
A Sensitive Method for Identification of DNA Dependent DNA Polymerases in Acrylamide Gels after Seperation by Micro Disc Electrophoresis
Authors: Zöllner E. Jürgen , Müller Werner E.G. , Zahn Rudolf K.
Published: August 2018

DNA polymerase, disc electrophoresis, template affinity Two sensitive methods are described for detection of DNA dependent DNA polymerase activities in polyacrylamide gels after their fractionation by micro-disc electrophoresis.

One technique is based on the increase in fluorescence of the ethidium bromide complex with template polydeoxyribonucleotides brought about by the action of the polymerases. The sensitivity of the previously described technique has been enhanced. Another method, 14 fold as sensitive, uses radioactive precursors in the enzyme assay after electrophoretic separation; washing, slicing and counting allows to evaluate incorporation into acid insoluble polymer, requiring 3* 10" 2 units corresponding to approx. 0.02 /μg of E. coli DNA polymerase I preparation. Differing activities of polymerase species and differing template preferences may be investigated with these techniques.
Der Einfluß der Diffusion bei der Kontrastierung von Schnitten für die Elektronenmikroskopie / The Influence of Diffusion on the Change of Contrast in Sections for Electron Microscopy
Authors: Lippert Werner
Published: August 2018

The influence of diffusion on the site of biological objects in sections is estimated. In experiments it is shown that the penetration of fluid in the embedding material depends on the fluid, the embedding material, the temperature, and the time. The hardness of the embedding material becomes smaller by the fluid.
Ion Uptake and Transport through Barley Seedlings: Differential Effect of Cycloheximide
Authors: Läuchli André , Lüttge Ulrich , Pitman Michael G.
Published: August 2018

Cycloheximide inhibits transport of K through barley roots without affecting K uptake and accumulation in the root cells. The inhibitor acts upon protein synthesis but does not appear to uncouple respiration. Requirement of protein synthesis for ion transport through roots is possibly due to involvement of symplasmic transport or vesicular secretion into the xylem.
DNA Turnover in Growing Yeast after X-Irradiation
Authors: Eckstein Hans
Published: August 2018

Growing yeast cells incorporate radioactivity from labeled nucleotides, deoxynucleotides, deoxyadenosine, and deoxycytidine into acid-insoluble material. Most of these compounds are in­ corporated predominantly into RNA, only dTMP and dTTP serve as effective and selective DNA precursors.

When yeast is prelabeled with dTMP, “specific” radioactivity of DNA decreases in the growing cells due to DNA augmentation. In X-irradiated yeast, “specific” radioactivity of DNA again decreases remarkably, though DNA augmentation of the growing giant cells in delayed. Simultaneously, radioactivity is rendered acid-soluble. Vice versa, X-irradiated unlabeled yeast incorporates radioactivity from labeled precursors into DNA, even if the DNA content of the cells does not increase.

When growing yeast cells are treated with cycloheximide, protein synthesis and DNA augmen­ tation are inhibited completely with 5·10-6 ᴍ cycloheximide. The decrease of “specific” radioactivity of DNA in X-irradiated cells, however, proves independent on an intact protein synthesis, even with 1·10-4 ᴍ cycloheximide.

The data provide clear evidence on DNA turnover in growing yeast after X-irradiation.
The Influence of Hydrogen Donors on Breakage of Parental DNA Strands and on Biological Activity of Transforming BrU-DNA of B. subtilis after 302/313 nm Radiation
Authors: Köhnlein Wolfgang
Published: August 2018

Long wavelength UV irradiation (302/313 nm) of hybrid and bifilarly labeled BrU-DNA of B. subtilis results in a degradation of the molecular weight of BrU and of parental thymine con­ taining DNA strands. Hydrogen donors present during UV irradiation are able to prevent these “primary” and “secondary” strand breaks. The protection factors are especially large for secondary breaks in parental normal DNA. Through the action of protective agents the biological activity could not be restored. The generation of these primary and secondary strand breaks due to BrU incorporation and the action of hydrogen donors discussed.
Studies on the Melting of DNA
Authors: Das Gokul Chandra
Published: August 2018

The thermal denaturation of the native DNA in solvents of varying salt concentrations was studied by viscometric and spectrophotometric methods. It was observed that within the molarity range of 0.02 ᴍ to 0.3 ᴍ, the melting temperatures obtained by the two independent methods agreed well, but that at lower ionic strength the agreement was not satisfactory. Both the visco­metric and the spectrophotometric measurements showed an increase of the melting temperature with increasing counterion concentration and a levelling off effect in the neighbourhood of 0.3 ᴍ.
Viscometric Studies on the Stability of DNA-Proflavine Complex-II
Authors: Das G. C. , Das N. N.
Published: August 2018

The binding of proflavine to native DNA increased its stability against thermal denaturation as measured by viscometric method. Up to a moderate ionic strength of 0.058 ᴍ, the melting temperature of the complex increased almost linearly with the increase of dye concentrations and a saturation was reached when one proflavine molecule was added per four to five DNA-Phosphates (D/P≅0.2). The extent of stabilization (ΔTm) produced by dye binding decreased gradually with the increase of ionic strength and no stabilization effect was observed at an ionic strength of about 0.3 ᴍ. The maximum melting temperature attained by Proflavine binding was almost independent of the ionic strength of the medium. The same maximum value was reached as obtained simply by increasing the sodium ion concentration.
Zur Chemotaxonomie der Corviden, II. Die Bürzelsekrete von Eichelhäher (Garrulus glandariusJ, Elster (Pica pica), Alpendohle (Pyrrhocorax graculus) und Kolkrabe ( Corvus corax) / Chemotaxonomy of Corvidae, II. The Uropygial Gland Secretion from the Jay (Garrulus glandarius), Magpie (Pica pica), Alpine Chough (Pyrrhocorax graculus), and Raven (Corvus corax)
Authors: Poltz Jens , Jacob Jürgen
Published: August 2018

The uropygial gland fats from four species of the family Corvidae are found to be mainly mono­ ester waxes, which consist of mono-, di-, and trimethyl substituted fatty acids and n- and methyl-branched alcohols. The positions of all methyl brandlings are even-numbered, the 2-position is preferred.

About 2 - 40% of the secretions consist of triester waxes: Alkyl-hydroxy-malonic acids esterified with n-fatty acids and n-alcohols. Waxes of this type are very common in the uropygial gland fats of birds and therefore, in opposite to the monoester waxes, they are not usable for a chemotaxo­ nomy of birds.
Acid-Soluble Deoxynucleotides and DNA Synthesis in Growing Yeast after X-Irradiation, II. Synthesis of Deoxynucleoside Tri- and Monophosphates in Synchronized and Asynchronously Growing Cells
Authors: Eckstein Hans , Ahnefeld Sybille , Albietz-Loges Karin
Published: August 2018

The behaviour of acid-soluble DNA precursors in synchronized and asynchronously growing yeast after X-irradiation is investigated by labeling techniques with 32Pi and by enzymic estimation. In prelabeled synchronized growing cells, radioactivity associated with deoxynucleoside triphosphates increases to maximum values shortly before each DNA replication, followed by a drastic decrease during S-phase. Radioactivity associated with monophosphates fluctuates, too, but with an opposite rhythm. These fluctuations apparently reflect quantitative changes of the DNA precursor pool during a cell cycle, as judged from the following findings: 1. Acid-soluble phosphorus is augmented stepwise. 2. "Specific" radioactivity from acid-soluble phosphorus compounds decreases steadily, indicating a continuous dilution of the labeled phosphorus pool with "cold" phosphorus. 3. Radioactivity associated with ribonucleotides fluctuates, too, but with a divergent rhythm.

In X-irradiated synchronice growing yeast, the fluctuations of the deoxynucleotide-associated 32P are disturbed only little. Maximum values appear nearly at the same time as in the control, they decrease to minor values even if DNA augmentation is delayed. This decrease is less drastic, however, than that during DNA replication in unirradiated yeast, yielding a slightly increased aver­ age label per generation time. At the same sime a rapid augmentation of monophosphate label is observed.

A pronounced increase of deoxynucleotide-32P is seen with X-irradiated asynchronously growing yeast, pointing to distinct radiosensitivities of the DNA/DNA precursor system in different cell stages. Neither 32P-fluctuations nor 32P-accumulation during DNA delay can be explained by cor­ responding observations with acid-soluble phosphorus or with ribonucleotide pools. Studies on 32P-incorporation also exclude radiation effects on cellular phosphorus uptake. Enzymic estimations of the deoxynucleoside triphosphate pools from asynchronously growing yeast rather exhibit a considerable increase of these substances during the radiation-induced delay of DNA augmentation. This accumulation of DNA precursors probably is caused by undisturbed synthesis, but reduced incorporation into DNA. The possible role of DNA repair in this system is discussed.
Die Röntgenstrukturanalyse von 2-(m-Brombenzyl-4.7.8.9- tetra-O-acetyl-N-acetyl-α -ᴅ-neuraminsäure * / X-Ray-Structure-Analysis of 2-(m-Br-benzyl) -4,7,8,9-tetra-O-acetyl-N-acetyl- α-ᴅ-neuraminic Acid
Authors: Wawra H
Published: August 2018

The structure of 2-(m-Br-benzyl) -4,7,8,9-tetra-O-acetyl-N-acetyl-α-ᴅ-neuramine acid was solved by heavy-atom methods using three-dimensional X-ray data. Known biochemical properties of the molecule allow to determine the absolute configuration.
Trägergebundenes Analog des Actinomycins C1 (D) und Affinitäts­ chromatographie von Nucleinsäuren / Resin Linked Analogue of Actinomyein C1(D) and Affinity Chromatography of Nucleic Acids
Authors: Seela Frank
Published: August 2018

A biospecific adsorbent for the separation of different nucleic acids was prepared by covalent attachment of a chromophore analog of actinomycin C1 (D) to Sepharose 4 B. The immobilized chromophor-derivative was obtained by condensation of 2-nitro-3-hydroxy-4-methylbenzoic acid with N6-(6-aminohexyl)-Sepharose 4 B, reduction of the nitro group and oxidative coupling with 2-amino-3-hydroxy-4-methylbenzoyl-β-(N,N-diethylamino) -ethylamide. Since the chromophore of actinomycin has a high affinity to DNA. DNA/RNA-mixtures were separated by retardation of DNA on this resin
Solubilisierung, Anreicherung und Separierung zweier 17β-HSDAktivitäten nach Phospholipase-Behandlung / Microsome-Associated 17β-Hydroxysteroid Dehydrogenases of Human Placenta, I Solubilization, Enrichment and Separation of Two 17β-HSD-Activities after Phospholipase-Treatment
Authors: Pollow Kunhard , Runge Wilfried , Pollow Barbara
Published: August 2018

Treatment of human placenta microsomes with phospholipase A or D inhibits the 17β-hydroxysteroid dehydrogenase [17β-HSD] activity, parallel with the hydrolysis of membrane phospholipids.

The 17β-HSD activity of phospholipase treated microsomes is reactivated by synthetic phospholipids. The distribution of 17β-HSD activity in subfractions of original microsomes and of phospholipase treated microsomes obtained by zonal centrifugation was studied.

Solubilization of the microsomal 17β-HSD was achieved by phospholipase A treatment. Two 17β-HSD were solubilized from human placenta microsomes by phospholipase A treatment and were further purified by ammonium sulphate precipitation, gel filtration on BioGel A-0.5 m, DEAESephadex chromatography and by isoelectric focusing. The enzymes were purified 25.8 and 17.4 times. The isoelectric points and molecular weights of the two 17β-HSD were determined.

Both enzymes are of a 17β-HSD type. One of the 17β-HSD, however, was sensitive to estradiol- 17β, the other to testosterone. The question of whether the two enzymes constitute a monomer and a dimer of the same 17β-HSD or are completely different enzymes, is discussed.
Kinetische Untersuchungen und Charakterisierung der solubilisierten Oestradiol-bzw. Testosteron-"sensitiven" 17 β-HSD-Aktivitäten / Microsome-Associated 17β-Hydroxysteroid Dehydrogenases of Human Placenta, II Kinetic Studies and Characterization of the Solubilized Estradioland Testosterone-“Sensitive” 17β-HSD-Activities
Authors: Pollow Kunhard , Runge Wilfried , Pollow Barbara
Published: August 2018

Detailed enzyme kinetic parameters of the reactions catalyzed by the two 17β-hydroxysteroid dehydrogenases (17β-HSD), which were solubilized from the microsomes of human placenta by treatment with phospholipase A, followed by enrichment and separation were determined.

Both enzymes are strictly substrate specific. The most active substrate of one of the 17β-HSD (fraction A) is estradiol-17β, the other 17β-HSD (fraction B) is sensitive to testosterone. Both NAD and NADP can serve as hydrogen transferring coenzymes, the latter giving about one-third of the initial rate of the former. With respect to the influence of temperature, different buffers and pH values, Michaelis constants [Km] with estradiol-17β and testosterone as substrates, the solubilized and separated microsomal 17β-HSD behave like those isolated from the cytoplasmic fraction.

The two 17β-HSD, after solubilization from the microsomal fraction of human placenta, enrichment and separation from each other, show only a little activity for the transfer of hydrogen between C17 of estradiol-17β and C17 of androstenedione. On the other hand, intact microsomes and an integrated system prepared by recombination of the 17β-enzymes by preincubation in phosphate buffer are able to catalyse very actively the transfer of hydrogen between estradiol-17β and androstenedione.

The effect of temperature and time on the recombination of the two enriched and separated microsomal enzyme activities and the determination of the pH-optimum of the hydrogen transfer reaction are described. Finally it is proposed that the hydrogen transfer between steroid hormones represents an aspect of the true reaction mechanism of steroid hormones: Steroid hormones function as hydrogen transferring coenzymes by forming part of a chain of hydrogen carriers.
Einfluß von Cytoplasma-und Serumfaktoren auf den [3H]Thymidintriphosphat-Einbau isolierter Leberzellkerne / Effect of Cytoplasmic and Serum Factors on the Uptake of [3H]Thymidinetriphosphate (TTP) by Isolated Nuclei of Liver Cells
Authors: Volm M. , Merz G.
Published: August 2018

The actions of cytoplasm (ultracentrifuged supernatant 105 000 x g) and of serum on the DNA synthesis (uptake of [3H]TTP) by isolated nuclei of liver cells were studied. Cytoplasm from liver cells obtained at various intervals after partial hepatectomy revealed a variable effect only with isolated nuclei of liver cells from partially hepatectomized rats. Cytoplasm obtained from liver cells eight hours after p artial hepatectomy failed to show the usual inhibitory effect. Presum ably the inhibitory substances norm ally present in cytoplasm are inactivated within a certain time after partial hepatectomy.

Serum of partially hepatectomized anim als enhanced the uptake of [3H]TTP by nuclei of normal liver cells and those from partially hepatectom ized animals. The stim ulating effect was present only in the serum obtained between four and twelve hours after partial hepatectomy. It remains unclear whether the effects described are growth factors specific for the liver.
Synthesis of Further Substrates of NAD(P)-Linked Dehydrogenases of High Specific Tritium Content
Authors: Alizade Miguel , Simon Helmut , Bressler Rubin , Brendel Klaus
Published: August 2018

Stereospecific, Hydrogen Labeled The preparation of (R) and (S) [2-3H] lactate as well as (S) [2-3H] glutam ate via the coupled exchange reaction catalyzed by NAD linked dehydrogenases and NADH : lipoam ide oxidoreductase (diaphorase) is described. The specific radioactivity of the hydrogen ions of the 3HOH /H2O can be obtained in the substrates (100% exchange) if equilibrium isotope effects are disregarded. By the exchange procedure substrates w ith higher specific radioactivity are obtained from positionally [3H] labeled racem ic m ixtures prepared by chemical reductions with [3H] labeled hydrides. The tritium content of one of the enantiom eres is “washed out” into water. As examples are presented the preparation of (R) [2-3H] (S) [2-H] malate as well as the corresponding carnitine, glutam ate and (R) and (S) lactate.
Charakterisierung von RNA aus synchron wachsender Bäcker-Hefe ( Saccharomyces cerevisiae) bei Trennung mit der Methylalbumin-Kieselgur(MAK)-Säule / Characterisation of RNA from Synchronously Growing Yeast Cells (Saccharomyces cerevisiae) as Separated by Columns of Methylated Albumin on Kieselgur (MAK)
Authors: Braun R.
Published: August 2018

Total RNA, extracted from synchronously growing yeast cells by the method of Georgiev-Mantieva, was separated by columns of methylated albumin on Kieselgur (MAK). By comparison with definited RNA’s in discelectrophorese and after pulse labelling with [3H] methionine the following fractions are identified: t-RNA, 5.8S RNA, m-RNA, 18S and 25S r-RNA and their precursors 20S, 27S and 35S. High molecular fractions of RNA between 40S and 70S were also found
Inhibition of Excision Repair without Influence upon UV-Sensitivity and UV-Mutability in Escherichia coli B/r Hcr+
Authors: Balgavý Pavel , Turek Robert
Published: August 2018

Pre-irradiation starvation of exponentially growing Escherichia coli B/r Hcr+ thy-trp- strain for thymine and tryptophan causes inhibition of pyrimidine dimer excision from ultraviolet damaged cells DNA. This inhibition of excision repair has not resulted in increasing ultraviolet sensitivity nor in increasing frequency of ultraviolet induced tryptophan revertants. The possible mechanisms of the non-excision repair in the prestarved cells, which is at least as accurate and effective as the whole dark repair in exponentially growing cells, are discussed.
Chemical Constituents of the Essential Oils of Aroliaceae and Lauraceae Families
Authors: Hayashi Nanao , Yokochyô Kôki , Komae Hisashi
Published: August 2018

In the course of the chemosystematic study of Aroliaceae and Lauraceae families, the leaf oils of some plants were investigated. The leaf oils were obtained by steam distillation of the fresh leaves. The individual constituents were isolated by column chromatography followed by preparative gas chromatography, and identified by gas chromatography and by infrared spectra.
Gaschromatographisch-massenspektrometrische Analyse neutraler und saurer Oligosaccharide der Frauenmilch als Trimethylsilyläther / Gas Chromatographic Mass Spectrometric Analysis of Neutral and Acid Oligosaccharides from Human Milk as Their Trimethylsilyl Derivatives
Authors: Nicolai Hubertus von , Egge Heinz , Zilliken Fritz
Published: August 2018

Gas chromatography and the 20 eV mass spectra of the human milk oligosaccharides fucosido-galactose, fucosido-lactose, di-fucosido-lactose, 3'-N-acetylneuraminyl-lactose, 6'-N-acetylneuraminyl-lactose and of N-acetyllactosamine as pertrimethylsilyl (TMS) ethers are described.

The gas chromatographic separation of the L-fucose containing oligosaccharides was performed on Silicone SE 30. The sialic acid containing sugars were separated on DEXSIL 300.

The correlations between oligosaccharide structures and mass spectrometric fragmentation pat­ terns are discussed.
Molecular Size of the Diapause Hormone of the Silkworm Bombyx mori
Authors: Kubota Ichiro , Isobe Minoru , Goto Toshio , Hasegawa Kinsaku
Published: August 2018

The diapause hormone (D H) responsible for arrested development of the silkworm Bombix mori consists of two active principles of peptide (A and B) . Since both hormones form aggregates in aqueous phases, the molecular weights were determined by gel permeation chromatography of Merckogel OR 6000 using methanol-dichloromethane mixture as the developing agent. Gramicidins and modified peptides soluble in the organic solvents were used as the standard markers for the molecular weight measurements of the hormones. The molecular weights of DH -A and -B are estimated to be 3300 ± 400 and 2000 ± 200, respectively.
6.7-Dihydroxycumarin (Aesculetin) als Substrat der Catechol-O-Methyltransferase / 6,7-Dihydroxycoumarin (Aesculetin) as a Substrate for Catediol-O-methyltransferase
Authors: Müller-Enoch D. , Seidl E. , Thomas H.
Published: August 2018

6,7-Dihydroxycoumarin (Aesculetin) was found to be a substrate of rat liver Catechol-O-methylfransferase (COMT) (EC 2.1.1.6).

Incubation of this substrate with S-Adenosyl-ʟ-[methyl-14C] methionine and/or S-Adenosyl- methionin-hydrogensulfate in the presence of COMT yields the highly fluorescent compounds 7-hydroxy-6-methoxycoumarin (Scopoletin) and 6-hydroxy-7-methoxycoumarin (Isoscopoletin) in the ration of about 2:1. The O-methylated products obtained from Aesculetin were identified after separation by thin layer chromatographpy mainly by the reversed isotope dilution technique.

The fluorescence of the isolated methylethers was proportional to concentration within the range from 10-5 - 10-7M. A reciprocal plot of activity versus substrate concentration gives a Km of 1 × 10-6 M.
Notizen: Hohe 3-Indolylessigsäure- und Phenylessigsäure- Konzentrationen in den Pygidialdrüsen von Wasserkäfern (Dytiscidae)/ High 3-Indoleacetic Acid- and Phenylacetic Acid- Concentrations in the Pygidial Glands of Water Beetles (Dytiscidae)
Authors: Dettner Konrad , Schwinger Gerhard
Published: August 2018

In pygidial-glands of water beetles (Dytiscidae) 3-indoleacetic acid and phenylacetic acid have been identified by mass-spectroscopical methods and estimated by UV-spectrometry.
Erster Nachweis von freien Cilien im Mitteldarm von Arthropoden / Discovery of Cilia in the Mid-Gut of Arthopoda
Authors: Rieder Norbert , Schlecht Friedrich
Published: August 2018

Cells bearing two cilia are found in the mid-gut of the Phyllopod Leptestheria dahalacensis. These cells seem to be sensory cells. They may be in contact with the muscle cells of the mid-gut.
Untersuchungen zur Biogenese der Cardenolide in Convallaria majalis L.: Umwandlungen auf der Geninstufe / Cardenolide Biogenesis in Convallaria majalis L.
Authors: Kopp Brigitte , Löffelhardt Wolfgang , Kubelka Wolfgang
Published: August 2018

[19-3H ] Strophanthidol, fed to leaves of whole plants of Convallaria majalis L., was translocated to the rhizomes and roots. Oxidation to [19-3H] strophanthidin took place in the leaves only. No labelled glycosides of strophanthidol and strophanthidin were found; thus, the aglycones are not precursors of the respective glycosides. It is assumed that the first glycosidation occurs at the C-21 level.
Dependence of Cellular Surface Area on Growth Density of 3T3 and SV40-3T3 Cells
Authors: Seher J.-P. , Adam G.
Published: August 2018

The cell surface areas of 3T3 and SV40-3T3 cells both for suspended and for flat cells growing on the culture substrate have been determined in dependence on growth density. The surface areas of flat 3T3 and SV40-3T3 cells turn out to be independent of growth density over a wide range. For 3T3 cells the surface area of flat cells com pares well with that determined by Collard and Temmink for suspended 3T3 cells taking the surface area of their coverlayer of microvilli into account. This indicates that upon suspension of flat 3T3 cells the surplus surface area is disposed of in the form of microvilli. For SV40-3T3 cells we obtained a surface area of flat cells which differs by a factor of about two from that of suspended cells as determined by Collard and Temmink including the surface area of microvilli.

Microscopical diameters and electrical (“Coulter”) volumina of suspended 3T3 and SV40-3T3 cells depend only little on cell density in the range investigated.
Verbreitung von Iridoiden in der Gattung Verbena und einigen anderen Verbenoideae / Iridoids in Verbena and Some Other Verbenoideae
Authors: Milz Sabine , Rimpler Horst
Published: August 2018

12 species of the genus Verbena and one Citharexylum species have been examined for iridoids. Besides the known compounds verbenaline, hastatoside, griselinoside, lamiide, ipolamiide and brasoside, two new iridoids, pulchelloside I (1) [2] and pulchelloside II (2) [3] have been isolated from Verbena species. The structures and absolute configurations of pulchelloside I and II have been determined by spectroscopical methods and some chemical reactions. Citharexylum solanaceum has been shown to contain lamiide and durantoside I. The distribution of the iridoids is in excel­ lent agreement with the taxonomic treatment of the genus Verbena by Schauer. The taxonomic significance of our data and some data from the literature regarding the classification of the sub­ family Verbenoideae is discussed.
Incorporation of 5-Bromo-2-deoxyuridine into the Chloroplast DNA of Anemia phyllitidis
Authors: Šonka J. , Schraudolf H.
Published: August 2018

5-Bromo-2-deoxyuridine, DNA, Chloroplasts, Fern 5-Bromo-2-deoxyuridine (BUdR) is incorporated into chloroplast DNA of Anemia phyllitidis. A possible connection between previously published effects of BUdR and on chloroplast ultrastructure and transitions caused by the base analogue in the DNA is referred to.
Complex Influence of Cytochalasin B on Actin Polymerization
Authors: Dancker P. , Low I.
Published: August 2018

In the presence of very low concentrations (about 2 x 10-7 ᴍ) of cytochalasin B (CB) the time course of actin polymerization is much more sigmoidal when followed by viscosity measurements than when followed by light scattering measurements. This suggests that under these conditions actin polymers do not immediately reach their final length but only via short ”bent“ polymers which can be detected only by light scattering but not by viscosity measurements. At higher CB concentrations (about equimolar to those of actin) CB reduces the average degree of polymerization and favors the nucleation step necessary for polymerization.