Zur Empfindlichkeit der Methode der Kupferchloridkristallisation Christine Ballivet, Haijo Knijpenga, Jean-Georges Barth, Raymond Clad
The Copper chloride crystallisation in the presence of added substances is a sensitive process. The significance of its results in the different fields of application (research on food qualityand medicine, for example), is often questioned because of poor reproducibility. The questionhas thus arisen as to the significance of the experimental conditions for the pattern ofcrystallisation. In this article, this question is discussed for some experimental parameters at agiven temperature. It determines the concentration – and interfacial surface tension gradientsin the solution. But the latter are limited by the sort and quantity of the added substances andthe interaction of the solution with the crystallisation plates and rings. Furthermore, theinfluence of the cleansing procedure on this interaction is shown. This influence in its turn isdependent on the duration of evaporation and on the nature of air movement. Thus theinfluence of one factor can change the influence of the other. This labile situation underliesthe sensitive crystallisation process. In order to permit the specific influence of the addedsubstance to express itself optimally, the corresponding conditions have to be found. But thisoptimum is not an absolute one. It is dependent on what question is being asked and of thenature of the addition.
Die Kristallisation von Kupferchlorid im Beisein eines Lösungsgenossen ist ein von vielenFaktoren abhängiger empfindlicher Prozess, was die Reproduzierbarkeit der Ergebnissebeeinflusst. Die hier vorgestellten Arbeiten gehen auf verschiedene Aspekte derVersuchsbedingungen ein. Ziel ist die Identifizierung wesentlicher Parameter, um dieVersuchsbedingungen herauszuarbeiten, die zur Verbesserung der experimentellenReproduzierbarkeit und diagnostischen Aussagekraft beitragen. Die Gleichnissprache der Mathematik Gerhard Kowol
In modern science the opinion predominates that the sensible reality can be explained bymeans of smallest components (elementary particles, genes). Goethe’s view is quite opposite. He says that the simple and imperfect elements can only be understood by looking at thecomposed and perfect objects. But the stupendous results of modern science make it difficultto argue in his direction. An analogous problem can be found within mathematics, if onelooks at the axiomatics of Euclidean geometry. Up to the end of the last century, the basicelements always have been points, lines and planes, but in modern times these have beenreduced to points alone. Since the mathematical theory itself does not differ in any way, itseems that the second view is preferable according to the minimum principle. But if one takesa superior point of view, which in this case means to pass over to projective geometry, itbecomes clear that this opinion is wrong. Science as process or dogma? The case of the Peppered Moth Craig Holdrege
The example of the Peppered Moth (Biston betularia) is widely viewed and presented as aclear proof of evolution through natural selection. A study of the primary literature reveals amuch more complex picture of the phenomena and of the process of scientific investigation.
This example can teach us to be critical of ‘scientific proofs’ and help us to view science as aprocess of interaction between the observer and the observed. This has significantimplications for science education.
Industrie-Melanismus und Birkenspanner (Biston betularia) gelten im Allgemeinen alsunumstößlicher Beweis dafür, dass natürliche Selektion die Evolution der Organismen steuert. Eine kritische Untersuchung der Primärliteratur zum Thema zeigt jedoch ein viel komplexeresBild von den Phänomenen und Prozessen wissenschaftlicher Untersuchung. Das Beispiel des Birkenspanners lehrt, so genannten wissenschaftlichen Beweisen gegenüberkritisch zu bleiben, und es hilft, Wissenschaft als Interaktion zwischen einem Beobachter undseinem Untersuchungsgegenstand zu verstehen. Diese Einsicht hat bedeutende Folgen für denwissenschaftlichen Unterricht an Schulen und Universitäten.
Law Council Diversity Policy DIVERSITY POLICY This policy provides the framework by which the Law Council actively manages and encourages diversity and inclusion across the organisation. This is an organisational policy only, and does not of itself give rise to any cause of action. This policy should be read in conjunction with the Law Council’s: Company Policies, including concerni
Cell Biochem Funct 2009; 27: 205–210. Published online 2 April 2009 in Wiley InterScience(www.interscience.wiley.com) DOI: 10.1002/cbf.1557In vitro effects of 2-methoxyestradiol on cell numbers, morphology,cell cycle progression, and apoptosis induction in oesophagealcarcinoma cellsVeneesha Thaver 1,2, Mona-Liza Lottering 2, Dirk van Papendorp 2 and Annie Joubert 2*1Department of Physiology,