On cylindrical container sections for a capillary free-surface experiment

Small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. These shifts can be used as a basis for accurate determination of contact angle. The authors describe container shapes, designed for a forthcoming USML-2 experiment, in the form of a circular cylinder with two diametrically opposed ``canonical proboscis`` protrusions. Computational studies indicate that these containers can be designed to have the desirable properties that sufficient liquid will participate in the shift to permit easy observation, but that the change will be abrupt enough to allow precise contact angle determination

Variety of Methodological Approach in Economics

It has been argued by some that the distinction between orthodox economics and heterodox economics does not fit the growing variety in economic theory, unified by a common methodological approach. On the other hand, it remains a central characteristic of heterodox economics that it does not share this methodological approach, but rather represents a range of alternative methodological approaches. The paper explores the evidence, and arguments, for variety in economics at different levels, and a range of issues which arise. This requires in turn a discussion of the meaning of variety in economics at the different levels of reality, methodology, method and theory. It is concluded that there is scope for more, rather than less, variety in economic methodologies, as well as within methodologies. Further, if variety is not to take the form of “anything goes”, then critical discussion by economists of different approaches to economics, and of variety itself, is required

Nonlinear Integer Programming

Research efforts of the past fifty years have led to a development of linear integer programming as a mature discipline of mathematical optimization. Such a level of maturity has not been reached when one considers nonlinear systems subject to integrality requirements for the variables. This chapter is dedicated to this topic. The primary goal is a study of a simple version of general nonlinear integer problems, where all constraints are still linear. Our focus is on the computational complexity of the problem, which varies significantly with the type of nonlinear objective function in combination with the underlying combinatorial structure. Numerous boundary cases of complexity emerge, which sometimes surprisingly lead even to polynomial time algorithms. We also cover recent successful approaches for more general classes of problems. Though no positive theoretical efficiency results are available, nor are they likely to ever be available, these seem to be the currently most successful and interesting approaches for solving practical problems. It is our belief that the study of algorithms motivated by theoretical considerations and those motivated by our desire to solve practical instances should and do inform one another. So it is with this viewpoint that we present the subject, and it is in this direction that we hope to spark further research.Comment: 57 pages. To appear in: M. J\"unger, T. Liebling, D. Naddef, G. Nemhauser, W. Pulleyblank, G. Reinelt, G. Rinaldi, and L. Wolsey (eds.), 50 Years of Integer Programming 1958--2008: The Early Years and State-of-the-Art Surveys, Springer-Verlag, 2009, ISBN 354068274

Iron and bismuth bound human serum transferrin reveals a partially-opened conformation in the N-lobe

Human serum transferrin (hTF) binds Fe(III) tightly but reversibly, and delivers it to cells via a receptor-mediated endocytosis process. The metal-binding and release result in significant conformational changes of the protein. Here, we report the crystal structures of diferric-hTF (Fe N Fe C-hTF) and bismuth-bound hTF (Bi N Fe C-hTF) at 2.8 and 2.4 Å resolutions respectively. Notably, the N-lobes of both structures exhibit unique 'partially-opened' conformations between those of the apo-hTF and holo-hTF. Fe(III) and Bi(III) in the N-lobe coordinate to, besides anions, only two (Tyr95 and Tyr188) and one (Tyr188) tyrosine residues, respectively, in contrast to four residues in the holo-hTF. The C-lobe of both structures are fully closed with iron coordinating to four residues and a carbonate. The structures of hTF observed here represent key conformers captured in the dynamic nature of the transferrin family proteins and provide a structural basis for understanding the mechanism of metal uptake and release in transferrin families. © 2012 Macmillan Publishers Limited. All rights reserved.published_or_final_versio

Pension reform, the stock market, capital formation and economic growth: a critical commentary on the World Bank's proposals

Abstract Proposing far-reaching reforms to the pension systems, the World Bank has recently suggested that the existing pay-as-you-go pension systems in many rich as well as poor countries, should be replaced by fully funded, mandatory, preferably private pensions, as the main pillars of the new system. It argues that these reforms will not only benefit the pensioners, but also enhance savings, promote capital formation and economic development. This paper provides a critical examination of the Bank's theses and concludes that it has adopted a one-sided view of the relationships between the key critical variables. The proposed reform may therefore neither protect the old nor achieve faster economic growth

Obstacles to compassion-giving among nursing and midwifery managers: an international study

Aim: To explore nursing and midwifery managers’ views regarding obstacles to compassion-giving across country cultures. Background: The benefit of compassionate leadership is being advocated, but despite the fact that health care is invariably conducted within culturally diverse workplaces, the interconnection of culture, compassion and leadership is rarely addressed. Furthermore, evidence on how cultural factors hinder the expression of compassion among nursing and midwifery managers is lacking. Methods: Cross-sectional, exploratory, international online survey involving 1 217 participants from 17 countries. Managers’ responses on open-ended questions related to barriers for providing compassion were entered and thematically analysed through NVivo. Results: Three key themes related to compassion-giving obstacles emerged across countries: 1. related to the managers’ personal characteristics and experiences; 2. system-related; and 3. staff-related. Conclusions: Obstacles to compassion-giving among managers vary across countries. An understanding of the variations across countries and cultures of what impedes compassion to flourish in health care is important. Implications for nursing practice and policy: Nursing mangers should wisely use their power by adopting leadership styles that promote culturally competent and compassionate workplaces with respect for human rights. Policymakers should identify training and mentoring needs to enable the development of managers’ practical wisdom. Appropriate national and international policies should facilitate the establishment of standards and guidelines for compassionate leadership, in the face of distorted organizational cultures and system-related obstacles to compassion-giving