975 resultados para iodine 123


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With a view to understanding the mechanism of the formation of 6-methoxy-2,2-(tetrachloro--phenylenedioxy)-naphthalen-1 (2H)-one (IIIa) in the reaction of 6-methoxy-1-tetralone (Ia) with tetrachloro-1,2-benzoquinone (II), the reaction of (II) with various tetralones and naphthols has been studied. Reaction with either α-tetralone or α-naphthol gives 2,2-(tetrachloro-o-phenylenedioxy)naphthalen-1 (2H)-one (IIIb), whereas reaction with either β-tetralone or β-naphthol gives a mixture of (IIIb) and ,1-(tetrachloro-o-phenylenedioxy)-naphthalen-2 (1H)-one (IX), with the former predominating. Further, reactions of (II) with 7-methoxy-3,4-dihydrophenanthren- 1 (2H)-one and m-methoxyphenol gave respectively 7-methoxy- ,2-(tetrachloro-o- phenylenedioxy)phenanthren-1 (2H)-one (VII) and 3-methoxy-6,6-(tetrachloro-o- phenylenedioxy)cyclohexa-2,4-dien-1-one (VIII). Structures of all these compounds have been proved on the basis of i.r. and n.m.r. data. The pathway to the formation of the condensates (III) is discussed.

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The absolute configuration of echitamine iodide has been determined by the Bijvoet technique, making use of the intensity differences between hkl and {Mathematical expression} reflections due to the anomalous scattering of CuKa radiation by the iodine atom. The various steps in the procedure are discussed in detail in this paper.

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The extra-vacuolar nucleus is visible in a small percentage of living cells from 72–96 hour wort cultures. The vacuoles show a luminous boundary under dark ground illumination. The details observed in living nuclei could be stained with haematoxylin after fixation in iodine-formaldehyde-acetic acid mixture. The Feulgen-negative nature of the vacuole and the limitation of the Feulgen-positive material to the area bounded by the nuclear membrane would imply that the ‘centrosome’ described by Lindegren and Rafalko (1950) is the real nucleus. The nucleus ofS. bayanus conforms in its structure to those of higher organisms.

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Iodimetric estimation of dialkyl dithiocarbamate in alcoholic solution is not accurate. The method has not met with success for the water-soluble dithiocarbamates before. A simple and accurate iodimetric method has been developed for the estimation of water-soluble dithiocarbamates. The success of the method is due to the removal of the oxidation product which interferes during the titration with iodine.

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Vegetative cells and zygotes of Saccharomyces carlsbergensis fixed in iodine formaldehyde acetic acid solution and stained after acid hydrolysis in hæmatoxylin, Feulgen and Giemsa show a remarkable similarity in the size and orientation of the structures in the nuclear matrix with reference to the nuclear membrane. The nucleolus described by Guilliermond may either be the chromocenter or the nucleolar equivalent.

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tRNA isolated from Image Image , grown in the presence of radioactive sulfur was analyzed for the occurrence of thionucleotides. The analysis revealed the presence of at least five thionucleotides, of which three were identified as 4-thiouridylic acid, 5-methylaminomethyl-2-thiouridylic acid and 2-thiocytidylic acid. Iodine-oxidation affected the acceptor ability of several amino acid specific tRNAs, those for lysine and serine being affected most. The tRNA of Image Image differs from that of Image . Image both in the number and the relative proportion of thionucleotides.

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The probability that a random process crosses an arbitrary level for the first time is expressed as a Gram—Charlier series, the leading term of which is the Poisson approximation. The coefficients of this series are related to the moments of the number of level crossings. The results are applicable to both stationary and non-stationary processes. Some numerical results are presented for the response process of a linear single-degree-of-freedom oscillator under Gaussian white noise excitation.

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Salmonella typhimurium mutants have been isolated in which phage P22 failsto establish lysogeny. These appear to be defective in cAMP metabolism. A phage mutation overcoming the bacterial defect has been mapped between gene c 1 and gene

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Tlie sclxuntion and clraractcrization of vitamins Al and An nnd related compoundsby reversed-pllasc paper cliromatogrnpl~y as well as ly thin-lqxr chromategraphy have hen rcportccl carlicrl * $. Thin-lnycr chromatography has also been used for the separatinn and charncterizatio11 of carotenoids from natural sourccs3~ ‘1. I-Iowcver, 130tr.rc,1~1~ofib scrvccl that carotenoid misturcs cannot be separated on a sin& aclsorhnt with ;1 sin& solvent. The scparntion and clctermi1wtion of carotenoid alclclydes from plants, microorganisms and animnl tissues have lxxn carriecl out by nicans of thin-layer clirf.~li~ato~apI~~U. Apocarotcnals awl apocarotcnoic acid have been detected in ornnges by the same technique’*

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The PI3-kinase pathway is the target of inactivation in achieving better cancer chemotherapy. Here, we report that p53-mediated transcription is inhibited by pharmacological inhibitors and a dominant-negative mutant of PI3-kinase, and this inhibition was relieved by a constitutively active mutant of PI3-kinase. Akt/PKB and mTOR, the downstream effectors of PI3-kinase, were also found to be essential. LY294002 (PI3-kinase inhibitor) pre-treatment altered the post-translational modifications and the sub-cellular localization of p53. Although LY294002 increased the chemosensitivity of cells to low concentrations of adriamycin (adriamycin-low), it protected the cells from cytotoxicity induced by high concentrations of adriamycin (adriamycin-high) in a p53-dependent manner. Further, we found that LY294002 completely abolished the activation of p53 target genes (particularly pro-apoptotic) under adriamycin-high conditions, whereas it only marginally repressed the p53 target genes under adriamycin-low conditions; in fact, it further activated the transcription of NOXA, HRK, APAF1 and CASP5 genes. Thus, the differential effect of PI3-kinase on p53 functions seems to be responsible for the differential regulation of DNA damage-induced cytotoxicity and cell death by PI3-kinase. Our finding becomes relevant in the light of ongoing combination chemotherapy trials with the PI3-kinase pathway inhibitors and underscores the importance of p53 status in the careful formulation of combination chemotherapies. Oncogene (2010) 29, 3605-3618; doi: 10.1038/onc.2010.123; published online 26 April 2010

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Several researchers are of the opinion that there are many benefits in using the object-oriented paradigm in information systems development. If the object-oriented paradigm is used, the development of information systems may, for example, be faster and more efficient. On the other hand, there are also several problems with the paradigm. For example, it is often considered complex, it is often difficult to make use of the reuse concept and it is still immature in some areas. Although there are several interesting features in the object-oriented paradigm, there is still little comprehensive knowledge of the benefits and problems associated with it. The objective of the following study was to investigate and to gain more understanding of the benefits and problems of the object-oriented paradigm. A review of previous studies was made and twelve benefits and twelve problems were established. These benefits and problems were then analysed, studied and discussed. Further a survey and some case studies were made in order to get some knowledge on what benefits and problems with the object-oriented paradigm Finnish software companies had experienced. One hundred and four companies answered the survey that was sent to all Finnish software companies with five or more employees. The case studies were made with six large Finnish software companies. The major finding was that Finnish software companies were exceptionally positive towards the object-oriented information systems development and had experienced very few of the proposed problems. Finally two models for further research were developed. The first model presents connections between benefits and the second between problems.

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This report presents a new theory of internal marketing. The thesis has developed as a case study in retrospective action research. This began with the personal involvement of the author in an action research project for customer service improvement at a large Australian retail bank. In other words, much of the theory generating ‘research’ took place after the original project ‘action’ had wound down. The key theoretical proposition is that internal marketing is a relationship development strategy for the purpose of knowledge renewal. In the banking case, exchanges of value between employee participants emerged as the basis for relationship development, with synergistic benefits for customers, employees and the bank. Relationship development turned out to be the mediating variable between the learning activity of employee participants at the project level and success in knowledge renewal at the organisational level. Relationship development was also a pivotal factor in the motivation and customer consciousness of employees. The conclusion reached is that the strength of relationship-mediated internal marketing is in combining a market focused commitment and employee freedom in project work to achieve knowledge renewal. The forgotten truth is that organisational knowledge can be renewed through dialogue and learning, through being trustworthy, and by gaining the trust of employees in return.

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We report on the dielectric proper-ties of bismuth aluminate and gallate with Bi:AI(Ga) ratio of 1: 1 and 12:1 prepared at high temperature and ambient pressure. These compounds crystallize in a noncentrosymmetric body-centered cubic structure (space group 123) with a similar to 10.18 angstrom rather than in the perovskite structure.This cubic phase is related to the gamma-Bi2O3 structure which has the actual chemical formula Bi-24(3+) (Bi3+Bi5+)O40-delta. In the aluminates and gallates studied by us, the Al and Ga ions are distributed over the 24f and 2a sites. These compounds exibit ferroclectric hysteresis at room temperature with a weak polarization. (c) 2006 Elsevier Ltd. All rights reserved.

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An application of Artificial Neural Networks for predicting the stress-strain response of jointed rocks under different confining pressures is presented in this paper. Rocks of different compressive strength with different joint properties (frequency, orientation and strength of joints) are considered in this study. The database for training the neural network is formed from the results of triaxial compression tests on different intact and jointed rocks with different joint properties tested at different confining pressures reported by various researchers in the literature. The network was trained using a three-layered network with the feed-forward back propagation algorithm.About 85% of the data was used for training and the remaining 15% was used for testing the network. Results from the analyses demonstrated that the neural network approach is effective in capturing the stress-strain behaviour of intact rocks and the complex stress-strain behaviour of jointed rocks. A single neural network is demonstrated to be capable of predicting the stress-strain response of different jointed rocks, whose intact strength varies from 11.32 MPa to 123 MPa, spacing of joints varies from 10 cm to 100 cm. and confining pressures range from 0 to 13.8 MPa. (C) 2010 Elsevier Ltd. All rights reserved.