bluuebunny/crossref_metadata_2025_split huggingface dataset:
The separation of aluminium from beryllium by ion flotation of an oxalato‐aluminate complex
Authors: Lusher J. A. , Sebba F. 
Published: July 2010

AbstractGood recovery (∼90%) of aluminium contaminated with up to 7% beryllium from a 2:1 molar aluminium/beryllium mixture is possible by flotation of the oxalate complexes at pH 4 with long‐chain fatty amines (especially tetradecylamine).
Catalytic synthesis of n‐propyl acrylate from acetylene, carbon monoxide and n‐propanol under pressure
Authors: Bhattacharyya S. K. , Bhattacharyya D. P. 
Published: July 2010

AbstractThe high‐pressure synthesis of n‐propyl acrylate from acetylene, carbon monoxide and n‐propanol has been studied in detail. Nickel iodide–silica gel (Ni : SiO2 = 50 : 50) and nickel acetate–silica gel (Ni : SiO2 = 50 : 50) were the most active catalysts (yields 58.78%, 55.54% respectively on acetylene input basis). Besides n‐propyl acrylate, the reaction product contains acrylic acid, acetaldehyde, liquid hydrocarbons, carbon dioxide, hydrogen, ethylene and other unsaturated hydrocarbons.
The physical toxicity of chemicals. V. Interaction terms for solubilities and partition coefficients
Authors: McGowan J. C. , Atkinson P. N. , Ruddle L. H. 
Published: July 2010

AbstractThe solubilities of anisole, phenetole, 1,3‐dimethoxybenzene and benzonitrile in water at 25° have been measured, and the partition coefficients of these compounds together withp‐toluonitrile between cyclohexane and water have been determined. Aromatic ether groups interact less with water than do aliphatic ether groups. Aromatic nitriles interact with water and appear to be associated in the liquid state and in concentrated solutions. The use of partition coefficients and solubilities for interpretation and prediction of toxicities is discussed.
Separation of aluminium from beryllium in aqueous solutions by precipitate flotation
Authors: Lusher J. A. , Sebba F. 
Published: July 2010

AbstractA fluoro‐complex of aluminium is selectively precipitated by sodium ion from a dilute aqueous solution aluminium, beryllium, fluoride and potassium ions at a pH near 3. Subsequent flotation of this precipitate with long‐chain alkylamines is affected by carbon chain length, pH, concentration of fluoride ion, rate of gas flow into the flotation cell and micellar form of the collector. Temperature has little effect on recovery.
Flotation of rutile with anionic and cationic collectors
Authors: Madeley J. D. , Graham K. 
Published: July 2010

AbstractResults are presented which indicate the effect of pH and flotation‐collector type upon the flotation rates of natural rutile particles. Above pH ∼2.5, flotation rate decreases with increasing pH for anionic collectors and increases with increasing pH for a cationic collector. These results are in agreement with expectations from the known electrokinetic properties of the mineral. Also, for a fixed pH, the rate of flotation is influenced by the length of the carbon chain associated with the collecting ion, and, for any one collector, by its concentration in solution. Below pH ∼2.5, the flotation rate with anionic collectors decreases with fall in pH, whereas with the cationic type a small increase in rate is shown as pH1 is approached.
The reaction between hydrazine and oxygen in water
Authors: Gaunt H. , Wetton E. A. M. 
Published: July 2010

AbstractStudies of the reaction between hydrazine and oxygen at 25° and 70° in alkaline solution have shown that the observed rate is due to catalysis by traces of impurities. It has been found that copper(II) and manganese (II) are the most active catalysts, and, under certain conditions, the copper(II)‐catalysed reaction appears to be homogeneous. Evidence is presented that catalysis occurs by redox reactions. The copper(II)‐catalysed reaction has been studied in some detail, but only the earlier stages fit a simple kinetic equation.
Catalytic synthesis of n‐butyl acrylate from acetylene, carbon monoxide and n‐butanol under high pressure
Authors: Bhattacharyya S. K. , Bhattacharyya D. P. 
Published: July 2010

AbstractThe reaction of acetylene, carbon monoxide and n‐butanol to form n‐butyl acrylate has been studied with several catalysts under a wide range of operating variables. Nickel iodide‐silica gel (Ni:SiO2 = 50:50) is the most effective catalyst with 80.3% conversion of acetylene to the ester. Nickel acetate‐silica gel (Ni:SiO2 = 50:50) is also a good catalyst (63% conversion). Other reaction products found were carbon dioxide, acrylic acid, acetaldehyde, saturated and unsaturated hydrocarbons, and polymeric products.
Catalytic conversion of ethanol to butadiene by two‐step process in fluidised bed
Authors: Bhattacharyya S. K. , Avasthi B. N. 
Published: July 2010

AbstractA detailed investigation on the two‐step conversion of ethanol to butadiene has been carried out in a fluidised bed using a large number of single and binary oxide catalyst systems. Al2O3 was the best catalyst among the single oxide catalyst systems whereas Al2O3‐ZnO (60 : 40) was most active among binary oxide catalysts. A maximum conversion of 43.8% was obtained with Al2O3‐ZnO (60 : 40) at a temperatures of 375° and a feed rate of 1.0 ml per h per ml of catalyst, the mole ratio of ethanol to acetaldehyde being 2.75 : 1.
The corrosion of zinc by vapours from polyester resins
Authors: Cawthorne R. , Flavell W. , Ross N. C. 
Published: July 2010

AbstractThe corrosion of zinc metal by vapours from cured styrene‐based polyester resins has been studied. The production of corrosive vapours has been found to be greatly influenced by the curing system. Peroxides of different types have been examined, some in the presence of accelerators. Resins cured by γ‐radiation, and by azodi‐isobutyronitrile, showed very low corrosion rates. Zinc formate was present in the corrosion products. It is suggested that the corrosion is due, at least in part, to the production of formic acid through oxidation of styrene monomer by the peroxidic catalysts, and the slow release of this acid by the cured resin.
Molecular engineering and validation of an oncolytic herpes simplex virus type 1 transcriptionally targeted to midkine‐positive tumors
Authors: Maldonado Arturo R. , Klanke Chuck , Jegga Anil G. , Aronow Bruce J. , Mahller Yonatan Y. , Cripe Timothy P. , Crombleholme Timothy M. 
Published: July 2010

AbstractBackgroundExpression profile analyses of midkine (MDK), a multifunctional protein important in development but repressed postnataly, indicate that it is highly expressed in approximately 80% of adult carcinomas and many childhood cancers including malignant peripheral nerve sheath tumors (MPNST). In the present study, we sought to leverage its selective expression to develop a novel oncolytic herpes simplex virus (oHSV) capable of targeting developmentally primitive cancers that express MDK.MethodsWe sought to increase the oncolytic efficacy of the virus by fusing the human MDK promoter to the HSV type 1 neurovirulence gene, γ134.5, whose protein product increases viral replication.ResultsTissue‐specific MDK promoter activity in human tumor cells and transgene biological activity was confirmed in human MPNST tumor cells. In vitro replication and cytotoxicity in human fibroblasts and MPNST cells by plaque and MTT assays showed that oHSV‐MDK‐34.5 increased replication and cytotoxicity compared to oHSV‐MDK‐Luc. By contrast, no significant difference in cytotoxicity was detected between these viruses in normal human fibroblasts. oHSV‐MDK‐34.5 impaired in vivo tumor growth and increased median survival of MPNST tumor‐bearing nude mice.ConclusionsThe transcriptional targeting of HSV lytic infection to MDK‐expressing tumor cells is feasible. oHSV‐MDK‐34.5 shows enhanced anti‐tumor effects both in vitro and in vivo. Further studies are warranted and may lead to its use in clinical trials. Copyright © 2010 John Wiley & Sons, Ltd.
Fragmentation behavior of a thiourea‐based reagent for protein structure analysis by collision‐induced dissociative chemical cross‐linking
Authors: Müller Mathias Q. , Dreiocker Frank , Ihling Christian H. , Schäfer Mathias , Sinz Andrea 
Published: July 2010

AbstractThe fragmentation behavior of a novel thiourea‐based cross‐linker molecule specifically designed for collision‐induced dissociation (CID) MS/MS experiments is described. The development of this cross‐linker is part of our ongoing efforts to synthesize novel reagents, which create either characteristic fragment ions or indicative constant neutral losses (CNLs) during tandem mass spectrometry allowing a selective and sensitive analysis of cross‐linked products. The new derivatizing reagent for chemical cross‐linking solely contains a thiourea moiety that is flanked by two amine‐reactive N‐hydroxy succinimide (NHS) ester moieties for reaction with lysines or free N‐termini in proteins. The new reagent offers simple synthetic access and easy structural variation of either length or functionalities at both ends. The thiourea moiety exhibits specifically tailored CID fragmentation capabilities—a characteristic CNL of 85 u—ensuring a reliable detection of derivatized peptides by both electrospray ionization (ESI) and matrix‐assisted laser desorption/ionization (MALDI) tandem mass spectrometry and as such possesses a versatile applicability for chemical cross‐linking studies. A detailed examination of the CID behavior of the presented thiourea‐based reagent reveals that slight structural variations of the reagent will be necessary to ensure its comprehensive and efficient application for chemical cross‐linking of proteins. Copyright © 2010 John Wiley & Sons, Ltd.
Mehrphasiges Wachstum von Mikroorganismen: Modellierung und Computersimulation linearer Wachstumsphasen
Authors: Knorre W. A. , Guthke R. , Bergter F. 
Published: July 2010

AbstractA phenomenological and a more causal model are developed for the multiphasic discontinuous growth. The first model distinguished between the lag‐phase, the exponential phase, the transient phase from the exponential to the linear phase, the linear phase, the transient phase from the linear to the stationary phase, and the stationary phase. The parameters are rate constants, critical values of biomass, and time constants. The parameters are estimated for experimental data of growth of Candida lipolytica under limitation of thiamine (MÜLLER et al. 1978).These data are fitted also by a more causal model. This second model is in agreement with Monod's idea that a linear growth phase may be due to an enzyme or enzyme system which has a constant activity. In the analysed case of limitation of thiamine the constancy of the dehydrogenase activity is caused by a constant level of the coenzymethiaminepyrophosphate. Thus, when such a thiamine requiring enzymatic step becomes to the „bottle‐neck”︁, bacterial culture switches over from exponential to linear growth. The end of linear phase is discussed more hypothetically by the high cooperativity of activity of dehydrogenases and the existence of a minimal specific growth rate.The results of modeling and parameter estimation are compared with experimental data of C. lipolytica. These two models are able to interpret the growth kinetic of these multiphasic growth.
Kinetics of petite mutation and thermal death in Saccharomyces cerevisiae growing at superoptimal temperatures
Authors: Simões‐Mendes B. , Madeira‐Lopes A. , van Uden N. 
Published: July 2010

AbstractMass formation of petite mutants took place in a strain of Saccharomyces cerevisiae when grown at superoptimal temperatures. After an initial period of exponential growth, a second period followed during which exponential death and net exponential petite mutation concurred with exponential growth. The specific rates of the three exponential processes were of the same order of magnitude and varied with the temperature. Net exponential petite mutation did not occur during the deathless first period of growth at superoptimal temperatures nor at any time during growth at suboptimal temperatures. Mitochondria are discussed as possible targets of thermal death in mesophilic yeasts.
Oxygen and „strictly anaerobic”︁ intestinal bacteria I. Effects of dissolved oxygen on growth
Authors: Uesugi I. , Yajima M. 
Published: July 2010

AbstractThe effects of oxygen on 29 strains of „strictly anaerobic„ bacteria, which are often found in human intestinal tracts, were studied. The initiation and rate of growth, together with the maximum extent of growth, in sealed L‐shaped tubes containing a medium through which a gas mixture containing 5% O2 had been bubbled were compared with those under anaerobic conditions. On the basis of the results, these anaerobic bacteria could be divided into three general types: Type A; strains which grew in almost the same way as under anaerobic conditions, type B; strains which grew less well than under anaerobic conditions, and type C; strains incapable of growth initiation in the initial presence of the dissolved O2. After the experiments no residual O2 was found in the medium of type A strains. The decrease in O2 concentration was small, if any, in media of type B and C strains.Using representative examples of these three types, physical changes in the culture medium accompanying growth were observed in a stirred fermenter equipped with three electrodes; Eh, oxygen, and pH. The results were as follows: Type A: Growth of Veillonella alcalescens in the fermenter started after the complete comsumption of dissolved oxygen and when Eh had dropped below ‐ 300 mV. A slight drop in pH occurred in parallel with the growth. Type B: In the culture of Bifidobacterium adolescentis, growth was simultaneous with the changes in O2 concentration, Eh, and pH. Type C: Growth of Bacteroides vulgatus was not initiated in the presence of the dissolved O2. Little change in O2 concentration, Eh or pH was observed.When bacterial cells which had grown in the medium initially containing dissolved O2 were subjected to serial transfer to similar fresh media, growth activity appeared to decrease progressively.
Suche nach pH‐abhängig wirkenden α‐L‐Arabino‐furanosidasen unter Vertretern derActinomycetales
Authors: Fleck W. , Passarge Margrit 
Published: July 2010

AbstractDie im Screening‐Programm eingesetzten Enzymsubstrate wurden ausgewählt auf Grund der Erfahrungen, wonach eine Reihe α‐l‐Arabinofuranoside cytotoxischer Phenole synthetisiert werden konnten, die wesentlich ungiftiger als die entsprechenden Aglykone sind (ARNDTu.GRAFFI1975,ARNDTY et al. 1976). Hinzu kommt, daß esSCHWABEet al.(1976) gelungen ist, ein relativ unwirksames α‐l‐Arabinofuranosid der cytotoxischen Substanz β‐Peltatin A zu synthetisieren. Im Screening‐Programm untersuchte Vertreter derActinomycetaleswurden der IMET‐Stammsammlung des Zentralinstituts für Mikrobiologie und experimentelle Therapie, Jena‐DDR, entnommen bzw. frisch aus Erdproben isoliert. Die Vorzucht der Mikroorganismen erfolgte für die Dauer von 2 Tagen bei 28 °C auf Schütteltischen in einem Flüssig‐Medium folgender Zusammensetzung: 1,5% Sojamehl, 1,5% Glucose, 0,1% CaCO3, 0,5% NaCl in Leitungswasser. Der Vorzucht folgte eine 4tägige Fermentation in einem Produktions‐Medium folgender Zusammensetzung: 2% Soja‐.
Metabolism of fructose in Thiocapsa roseopersicina
Authors: Conrad R. , Schlegel H. G. 
Published: July 2010

AbstractThiocapsa roseopersicina strain 6311 grew phototrophically in a mineral medium containing fructose as sole electron donor and carbon source with a doubling time of 11‐13 h, provided the mineral medium contained vitamine B12 (50 ng/ml), not more than 20 mM phosphate, and the culture was preincubated in the dark for 24 h. In fructose‐grown cells but not in autotrophically grown cells, the cell‐protein content was strongly reduced when vitamine B12 was growth limiting, while the carbohydrate content was increased. Growth on fructose as sole carbon source was inhibited by the addition of sulfide or thiosulfate; growth inhibition was relieved in the presence of bicarbonate. No growth on fructose was observed anaerobically in the dark; aerobic growth in the dark was poor. Analysis of enzyme activities in fructose‐ and acetate‐grown cells indicated that fructose was catabolized via fructose‐1‐phosphate and the EMBDEN‐MEYERHOF pathway. The operation of the EMBDEN‐MEYERHOF pathway was confirmed by incorporation of 1‐14C‐, 3‐14C‐, and 6‐14C‐fructose into the spirilloxanthin fraction and analysis of its specific radioactivity.
Eisenoxydierende, stäbchenförmige Bakterien II. Quantitative Untersuchungen zum Stoffwechsel und zur Eisenoxydation mit Eisen(II)‐oxalat
Authors: Kullmann K.‐H. , Schweisfurth R. 
Published: July 2010

AbstractDie von Schulze (1973) isolierten, auf Eisenoxalatmedium mit braunen Kolonien wachsenden Bakterien, St. 31 (ähnlich Pseudomonas denitrificans) und St. 68 (Protaminobacter ruber) wurden auf ihren Stoffwechseltyp hin untersucht. Dabei konnte keine autotrophe Lebensweise nachgewiesen werden. Die untersuchten Bakterien gehören zur Gruppe der heterotrophen Bakterien, die Eisen indirekt durch Verwertung der organischen Komplexbildner oxydieren, ohne die bei der Eisenoxydation freiwerdene Energie zu nutzen.Pseudomonas denitrificans gehört nach BERGEY (1974) zu den nicht identifizierten Arten und Stämmen, Protaminobacter ruber ist nach BERGEY (1974) wahrscheinlich identisch mit Bacillus extorquens (BASSALIK 1913).
Site of ATPase activity in Myxococcus xanthus: Lipid requirement for enzyme activity
Authors: Voelz H. 
Published: July 2010

AbstractTreatment of cells with lysophosphatidylcholine, lysozyme, and phospholipase D removed most of their phospholipids and reduced ATPase activity to near zero. Addition of a microdispersion of phospholipids restored enzyme activity to various degrees. Phosphatidylcholine was most effective in reconstitution experiments, less effective were phosphatidylethanolamine and phosphatidylserine. Lipid analyses of cell fractions were possible through separation of cell wall and cell membrane in a sucrose gradient after differentiated treatment of glutaraldehyde fixed cells with lysophosphatidylcholine, lysozyme, and pronase. Phosphatidylcholine was almost exclusively a component of the cell membrane, whereas phosphatidylethanolamine was that of the wall. It is concluded that lipids are necessary for in vivo function of a Mg‐dependent ATPase, and that membrane‐associated phosphatidylcholine may serve as a matrix for the enzyme. Lipid extracts made from cells or cell fractions contained plasmologens, not previously reported to occur in Gram‐negative, aerobic bacteria.
Lysinbiosynthese bei Pseudomonas aeruginosa PAO 1 I. Einfluß von Cetyl‐trimethyl‐ammoniumbromid auf P. aeruginosa PAO 1 bei der Bestimmung der DAP‐Decarboxylaseaktivität
Authors: Schröder D. , Wölfel L. , Schroeter A. , Mach F. 
Published: July 2010

AbstractMethoden zur Permeabilisierung von Bakterienzellen wurden in letzter Zeit verstärkt zur enzymatischen Charakterisierung herangezogen. Derartige Verfahren erfordern den Zusatz von Detergenzien oder anderer oberflächenwirksamer Substanzen, so daß eine normale Enzymreaktion ermöglicht wird (BARNES et al. 1969, DRAŽIČ u. VITALE 1975, VOLD et al. 1975, JACKSON u. DE MOOS 1969). Die hier beschriebenen Versuche wurden am Wildstamm von Pseudomonas aeruginosa PAO 1 durchgeführt und verfolgten das Ziel, die Einwirkung von Cetyl‐trimethylammoniumbromid (CTAB) auf die Zellen dieses Stammes bei der Untersuchung der Diaminopimelinsäure‐Decarboxylase (E.C. 4.1.1.20, meso‐2,6 diaminopimelate carboxylase) zu charakterisieren.
Ultrastructural characterization of stable L‐form cells from Erysipelothrix rhusiopathiae and of accompanying artifacts
Authors: Gumpert J. , Todorov T. , Toshkov As. 
Published: July 2010

AbstractThe stable L‐form of Erysipelothrix rhusiopathiae is a typical protoplast type L‐form. Cells are surrounded by a trilamellar cytoplasmic membrane only. They grow in form of aggregations in liquid media and their diameters vary between 0.1 and 2 μm. Always a large portion of cells undergoes lysis. It seems to be characteristic for L‐form cultures of E. rhusiopathiae that always many artifact structures are formed. The artifacts are spherical particles with diameters of 0.1 μm to more than 3 μm. They can be differentiated from L‐form cells only by electron microscopy. The artifacts consist of electron dense amorphous material and their surface is irregular without a clear boundary line. Obviously, these artifacts are produced from protein components of the medium and from cytoplasmatic components of the lysing L‐form cells.
Elektronenoptische Untersuchungen zur Wirkung von 1‐[p‐(Methylnitrosamino)‐benzylidenamino]‐adamantan auf das Fowl‐Plague‐Virus (FPV) in Zellkultur
Authors: Zöpel P. , Tonew E. , Ulbericht H. 
Published: July 2010

AbstractThe adamantanamine derivative 1‐[p‐(methylnitrosamino)‐benzylidenamino]‐adamantane (MBAA) at a concentration of 40 μg/ml demonstrated no effect on adsorption of fowl plague virus (FPV) on chick embryonal cells. The penetration of the virions took place by means of pinocytosis. In the final stages of penetration the virions became gradually disintegrated. Under the influence of MBAA, after break‐down of the membrane of pinocytic vesicles a swollen part of the virus core remained in cytoplasm. The morphologically visible replication stages were completely blocked by MBAA. From these results it was concluded that the antiviral action of MBAA most probably depends on a block of virus replication between the final stages of the penetration process and the beginning of production of virus specific structural antigens.
Roll der Formiat‐Dehydrogenase in „Serinweg‐Bakterien”︁
Authors: Babel W. , Mothes Gisela 
Published: July 2010

AbstractDie Formiat‐Dehydrogenase (E. C. 1.2.1.2.) kommt in allen — bisher untersuchten — „Serinweg‐Bakterien”︁ vor, und sie wird induziert durch Methanol und durch Formiat auch bei Bakterienstämmen mit konstitutiver Methanol‐Dehydrogenase, obwohl der von der Formiat‐Dehydrogenase katalysierte Schritt außerhalb des Assimilationszyklus liegt.Die Formiat‐Dehydrogenase ist bei hinreichend hoher Carbonatkonzentration im Wachstums‐medium für biosynthetische Reaktionen ohne Bedeutung. Sie ist für den Energiehaushalt dieser Bakterien wesentlich. Darauf weist hin, daß die energetisch negative Bilanz des Assimilationszyklus durch Einbeziehung der Formiat‐Dehydrogenase‐Reaktion positiver wird. Gegenüber ATP ist die Formiat‐Dehydrogenase — aus Pseudomonas methylica — unempfindlich. Da dieses Enzym mit der induktiven biosynthetischen Formyltetrahydrofolat‐Synthetase (E.C. 6.3.4.3.) um Formiat konkurriert und letzteres Enzym ATP als Substrat hat, kann ATP trotzdem das Gleichgewicht von Assimilation und Dissimilation allein via Massenwirkungsgesetz wirksam kontrollieren. Bei niedriger ATP‐Konzentration ist die bioenergetische Formiat‐Dehydrogenase begünstigt und bei hoher wird Formiat bevorzugt assimiliert. Aber wesentlicher für die Lage des Gleichgewichts scheint das NAD+/NADH‐Verhältnis, genauer gesagt, die NADH‐Konzentration zu sein, denn NADH hemmt die Formiat‐Dehydrogenase kompetitiv gegenüber NAD+ und nicht‐kompetitiv gegenüber Formiat.NADH spielt also im methylotrophen Stoffwechsel nicht nur die für andere Ernährungstypen (z. B. aerobe chemoorganoheterotrophe Ernährung) übliche Rolle, sondern es ist außerdem Substrat für biosynthetische Reaktionen und zentrale Regelgröße.