A Banach space $X$ has Pełczyński's property (V) if for every Banach space $Y$ every unconditionally converging operator $T\colon X\to Y$ is weakly compact. H. Pfitzner proved that $C^*$-algebras have Pełczyński's property (V). In the preprint (Krulišová, (2015)) the author explores possible quantifications of the property (V) and shows that $C(K)$ spaces for a compact Hausdorff space $K$ enjoy a quantitative version of the property (V). In this paper we generalize this result by quantifying Pfitzner's theorem. Moreover, we prove that in dual Banach spaces a quantitative version of the property (V) implies a quantitative version of the Grothendieck property., Hana Krulišová., and Obsahuje bibliografii
While fertility rates in Western countries are low and the number of people who will remain voluntarily childless is increasing, more and more couples are seeking medical treatment for infertility. Fertility problems transcend the boundaries of medicine and challenge the traditional positivistic understanding of health and illness and the authority of scientific and objective medicine. The circumstances for coping with infertility are not universal and depend instead on the given society and on cultural values. Studying infertility means studying every important institution of our society: the institutions of marriage and the family, the institution of parenthood, medicine, and so on. While American and other Western social scientists have studied social aspects of infertility for many years, in the Czech Republic the topic remains the domain of medicine. This article focuses on basic concepts employed in the study of infertility and involuntary childlessness in sociology. It presents and summarises relevant concepts such as stigmatisation, social exclusion, identity problems, and gender differences in the response to infertility. It presents the debate over explaining the terms of infertility and (involuntary and voluntary) childlessness. It shows how the position of involuntary childlessness has been changing as the problem has increasingly come to be dealt with in medical terms and as high-tech medical treatments for infertility have been developed. Finally, the article opens up the topic for debate and raises the question of potential methods of research.