Multiple spots on paper chromatograms

Zusammenfassung Bei der papierchromatographischen Prüfung bestimmter reiner Stoffe wurde die Bildung mehrerer Flecken beobachtet. Derartige ?ghost?-Flecken entstehen mit gewissen herzaktiven Glykosiden und auch mit dem Antibiotikum Monamycin.      

An adaptor for the beckman spectrophotometer for the reading of chromatograms and electropherograms

Riassunto Viene descritto un accessorio applicabile allo spettrofotometro diBeckman per la lettura di cromatogrammi e di elettroferogrammi. La luce proveniente dallo spettrofotometro viene trasformata, per mezzo di due lenti cilindriche, in una lunga e stretta banda che permette di risolvere anche righe tra loro vicine. Le letture possono essere praticate alla lunghezza d'onda desiderata. Esiste in tali condizioni una relazione diretta tra la quantità di sostanza in esame e l'area sottesa dalla curva ottenuta ponendo in grafico i valori di densità ottica nei vari punti della striscia in esame.     

An apparatus for the measurement of small tensions

Zusammenfassung Ein Apparat zur Messung von kleinen Spannungen in biologischem Material wird beschrieben. Das System wurde konstruiert, um Störungen durch Milieufaktoren sowie durch Temperatur- und Feuchtigkeitsvariationen und Vibrationen zu eliminieren.     

Quantitative analysis of absorption spectra and application to the characterization of ligand binding curves

The spectrum of a chromophore may change as a result of perturbations in its environment. The spectral changes resulting from the perturbation are often followed by measurements at just one or two wavelengths but it is usually no more difficult to collect entire spectra. The problem comes in analysing the data from such a series of spectra. In this paper we will suggest a simple procedure in which the spectrum observed under any particular set of conditions may be considered to consist of the sum of two distinct spectral forms. The method, which is free of any assumptions regarding the quantitative relationship between the perturbation and the extent of spectral change, defines any given spectrum in terms of an apparent molar fraction of the contributing spectral forms. The variation of this apparent molar fraction provides information from which a quantitative relationship can be developed to describe the dependence of the spectral change on the perturbant. The method is illustrated using the model system of phenol red protonation and is applied to the characterization of the binding of azide ions to cobalt-substituted carbonic anhydrase.     

Quantitative analysis of absorption spectra and application to the characterization of ligand binding curves

Summary The spectrum of a chromophore may change as a result of perturbations in its environment. The spectral changes resulting from the perturbation are often followed by measurements at just one or two wavelengths but it is usually no more difficult to collect entire spectra. The problem comes in analysing the data from such a series of spectra. In this paper we will suggest a simple procedure in which the spectrum observed under any particular set of conditions may be considered to consist of the sum of two distinct spectral forms. The method, which is free of any assumptions regarding the quantitative relationship between the perturbation and the extent of spectral change, defines any given spectrum in terms of an apparent molar fraction of the contributing spectral forms. The variation of this apparent molar fraction provides information from which a quantitative relationship can be developed to describe the dependence of the spectral change on the perturbant. The method is illustrated using the model system of phenol red protonation and is applied to the characterization of the binding of azide ions to cobalt-substituted carbonic anhydrase.     

An alternative decomplementation method for the measurement of the survival of human erythrocytes transfused into rats

Summary An alternative technique for measuring the survival of⁵¹Cr-labelled human erythrocytes transfused into rats is described, in which aggregated human gamma-globulin is substituted for cobra venom factor as a decomplementing agent.Acknowledgments. This work was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo and Conselho Nacional de Desenvolvimento Cientifico e Tecnológico.     

Scenario planning: An investigation of the construct and its measurement

Scenario‐planning academicians and practitioners have been observing for more than three decades the importance of this method in dealing with environmental uncertainty. However, there has been no valid scale that may help organizational leaders to act in practice. Our review of prior studies identifies some problems related to conceptualization, reliability, and validity of this construct. We address these concerns by developing and validating a measure of scenario planning based on Churchill's paradigm (Journal of Marketing Research, 1979, 16, 64–73). Our data analysis follows from a sample of 133 managers operating in the healthcare field in France. To validate our scale, we used three approaches: first, an exploratory factor analysis; second, an examination of psychometric proprieties of all dimensions; and third, a confirmatory factor analysis. The results of this study indicate that scenario planning is a multidimensional construct composed of three dimensions: information acquisition, knowledge dissemination, and scenario development and strategic choices.     

Preparation of serum for paper electrophoresis from small animals

Zusammenfassung 1 bis 2 Tropfen Blut werden in einer Kapillare 10 min bei 10 000 U/min zentrifugiert. Die Kapillare wird an der Schichtgrenze zerschnitten. Das Serum kann so leicht auf die Papierstreifen zur Elektrophorese aufgetragen werden.     

Detection of dipeptides and dipeptidase activity on paper

Riassunto Viene descritto un metodo rapido e sensibile per la rilevazione delle dipeptidasi su carta.