Search results for "TRANSFORMATION"
showing 10 items of 1634 documents
Chromatin structure of transposon Tn903 cloned into a yeast plasmid
1989
Transposon Tn903 contains the APH gene for kanamycin resistance, which is active in yeast [A. Jiménez and J. Davies (1980) Nature (London) 287, 869-871] and is flanked by two inverted repeats (IR) 1057 bp long. When plasmid pAJ50, carrying Tn903 and the 2-microns circle origin of replication, is cloned into Saccharomyces cerevisiae, nucleosomes are assembled in vivo on the prokaryotic DNA of the transposon. Indirect end labeling revealed that three nucleosomes are preferentially positioned on symmetrical sequences from both IRs. DNase I digestion also confirmed that the chromatin structure is symmetrical in both IRs. This suggests that sequence determinants are decisive for chromatin struct…
Development of an Efficient In Vivo System (P-junc-TpaseIS(1223)) for Random Transposon Mutagenesis of Lactobacillus casei
2012
ABSTRACT The random transposon mutagenesis system P junc -TpaseIS 1223 is composed of plasmids pVI129, expressing IS 1223 transposase, and pVI110, a suicide transposon plasmid carrying the P junc sequence, the substrate of the IS 1223 transposase. This system is particularly efficient in Lactobacillus casei , as more than 10,000 stable, random mutants were routinely obtained via electroporation.
Production of a Recombinant Catechol 2,3-Dioxygenase for the Degradation of Micropollutants
2017
Phenolic compounds such as catechol represent a particular type of micropollutant whose high stability prevents rapid decay and metabolization in the environment. We successfully cloned a catechol 2,3-dioxygenase (C2,3O) from Pseudomonas putida mt-2 and expressed it in Escherichia coli BER2566. The biomass isolated from shake-flask fermentations was used to partially purify the enzyme. The enzyme proved unstable in clarified liquid fractions (50 mM Tris buffer, pH 7.6) and lost more than 90% of its activity over 7 h at 25 °C. In the presence of 10% acetone, the process was slowed down and 30% residual activity was still present after 7 h incubation. Storage of the enzyme in clear liquid fr…
Species differences, influence of dose and application on biotransformation of phenol in fish.
1983
1. The metabolism of phenol in goldfish (Carassius auratus), rainbow trout (Salmo gairdneri) and goldenorfe ide (Leuciscus ideus melanotus) was compared. All three species produced phenyl sulphate, quinol sulphate and phenyl glucuronide. 2. The dose dependence of metabolism of phenol in goldfish was investigated. When the concn. of phenol was increased from 0.2 to 2 mg/l medium, that glucuronylated increased from 7 to 16% and that sulphated decreased from 63 to 47%. 3. The influence of mode of exposure on metabolism of phenol in goldfish was examined. Dietary exposure and uptake from medium was compared with i.p. injection. There was less metabolism in the order: dietary exposure greater th…
Liderazgo transformacional, capacidad de aprendizaje organizativo y felicidad en el trabajo
2013
En los últimos veinte años se ha producido un incremento de los artículos que buscan cómo mejorar el resultado económico en las empresas. No hay duda de la importancia que tiene esta variable como fin último de cualquier investigación, sin embargo, en este estudio queremos proponer una variable que consideramos de especial relevancia para la investigación en el área de organización de empresas como es la felicidad en el trabajo. La felicidad en general está directamente conectada con beneficios tan importantes como la salud física o mental, y las medidas que hasta ahora se han aproximado a la felicidad en el trabajo se han relacionado con variables tan importantes como la mejora de la motiv…
Weyl's theorem for perturbations of paranormal operators
2007
A bounded linear operator T ∈ L(X) on a Banach space X is said to satisfy "Weyl's theorem" if the complement in the spectrum of the Weyl spectrum is the set of all isolated points of the spectrum which are eigenvalues of finite multiplicity. In this paper we show that if T is a paranormal operator on a Hilbert space, then T + K satisfies Weyl's theorem for every algebraic operator K which commutes with T.
Reaching for different ends through tenure track—institutional logics in university career systems
2020
AbstractIn this study, we used the institutional logics perspective to identify the logics underpinning the tenure track career system, how the logics manifest themselves in recruitment and performance management and how academic leaders and academics negotiate between the logics. The study contributes to research on governance dynamics in academia and to universities’ organisational transformation in the context of strategic actorhood. The data comprised interviews with academic leaders (vice-rectors, deans, department heads) and academics in tenure track positions at two Finnish universities. Empirically, the study explores two key areas of human resource management: recruitment and perfo…
Automatic Reengineering in MDA Using Rewriting Logic as Transformation Engine
2005
Legacy systems are information systems that have been developed by means of methods, tools and database management systems that have become obsolete, but they are still being used due to their reliability. As time goes on, the maintenance of this software becomes more complex, expensive and painful. The MOMENT framework supports automatic formal model transformations in MDA. This model transformation approach is based on the algebraic specification of models and benefits from mature term rewriting system technology to perform model transformation using rewriting logic. In this paper, we present how we apply this formal transformation mechanism to recover a legacy relational database, obtain…
Min-max control of uncertain multi-inventory systems with multiplicative uncertainties
2001
In this note, we consider production-distribution systems with buffer and capacity constraints. For such systems, we assume that the model is not known exactly. More precisely, the entries of the matrix representing the system structure may be affine functions of some uncertain time-varying parameters that take values within assigned bounds. We give stabilizability conditions that can be checked, in principle, by solving a min-max problem on the surface of the state-space (buffer level space) unit ball. Then, we consider a special case in which each uncertain parameter affects a single column of the system matrix and is independent of all the other ones. In this case, we propose a mixed int…
Unitary transformations depending on a small parameter
2011
We formulate a unitary perturbation theory for quantum mechanics inspired by the LieDeprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained through a Magnus expansion. This ensures unitarity at every order in a small parameter. A comparison with the standard perturbation theory is provided. We work out the scheme up to order ten with some simple examples.