Specific aspartate residues in FET3 control high-affinity iron transport in Saccharomyces cerevisiae

Site-directed mutagenesis was performed on a set of six aspartate residues of Fet3, the multicopper ferroxidase involved in high-affinity iron transport in Saccharomyces cerevisiae, in order to comprehend the molecular determinants of the protein function. Asp312, Asp315, Asp319 and Asp320 were predicted by homology modelling to be located in a negatively charged surface-exposed loop of the protein. Other two aspartate residues (Asp278 and Asp279) are placed close to the type 1 copper- and iron-binding sites, possibly linking these sites to the negatively charged region. In vivo results showed that mutation of Asp319 and Asp320 to yield D319N and D320N derivatives strongly impairs the ability of the yeast to grow under iron-limiting conditions. In particular, substitution of Asp320 with asparagine essentially abolished the Fet3-dependent iron transport activity. All other mutants (D278Q, D279N, D312N and D315I) behaved essentially as the wild-type protein. The electron paramagnetic resonance spectrum of the soluble forms of D319N and D320N showed significant changes of the copper sites' geometry in D319N but not in D320N. At variance with the membrane-bound forms, soluble D319N and D320N derivatives were highly susceptible to proteolytic degradation, suggesting that replacement of Asp319 or Asp320 locally modifies the structure of Fet3, making the protein sensitive to proteolysis when it is not protected by the membrane environment. In turn, this might be evidence of a shielding role of the permease Ftr1, which could interact with Fet3 at the level of the aspartate-rich negatively charged region.     

"On the possible psychophysical laws" revisited: Remarks on cross-modal matching.

A nonrelational theory of cross-modal matching, including magnitude estimation, is proposed for the general class of 1-dimensional measurement structures that have real-unit (ratio and interval scale) representations. A key feature of these structures is that each point of the structure can be mapped into each other point by a translation, which is the structural analogue of ratio scale transformations of the representation. Let M denote a 1:1 matching relation between 2 (not necessarily distinct) unit structures. The major assumption is that for each translation τ of one structure, there is a translation ?τ of the other such that if xMs, then τ(x)M?τ(s). This property is shown to be equivalent to a power law holding between the unit representations. A concept of similar relations is taken from dimensional analysis, and 2 matching relations are shown to be similar if and only if their power laws differ only in the unit (modulus), not the exponent. A relation R between pairs in each system is said to be a ratio relation relative to a matching relation M satisfying the above condition provided that (x,y)R(s,t) obtains if and only if for some translation τ both τ(x)Ms and τ(y)Mt. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Review of A World of Difference: Gender Roles in Perspective.

Reviews the book, A World of Difference: Gender Roles in Perspective by Esther R. Greenglass (1982). In A World of Difference, Esther Greenglass has given us an excellent social-psychological perspective on sex, gender, and sex-role differences. Greenglass clearly analyses current research on these topics with the perspective of the culture in which gender-based behaviour occurs. Equally important, however, is the discussion of the social and cultural context of the research itself. Aside from this important and useful discussion of the research in its social context, there is a very thorough review of contemporary issues relating to gender roles. This is a very readable book for students. The collection of pictures and cartoons depicting contemporary male and female roles illustrates the issues while showing their humorous side. Throughout the book, there are examples of Canadian data and Canadian research which will make the book particularly appealing to those who find that U.S. texts are too chauvinistic about the American experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Concept design for quality in virtual environment

The early identification of the optimal concept is a critical task of the design process in order to increase the chances of satisfying customers. The challenging aspect of the approach proposed in this work relies in the quality evaluation of virtual prototypes of new industrial products (i.e. concept designs) by adopting a statistical procedure previously applied to service industries. Following this approach, the optimal concept design is defined at the end of a process consisting of five phases: identification of the quality elements of the concept design, classification of the quality elements, generation and quality evaluation of product concepts and, finally, definition of the optimal concept. Currently, virtual reality (VR) environment offers the opportunity to evaluate the characteristics of different virtual prototypes by involving experts and/or customers, overcoming the need for several physical prototypes. On the other side, the dynamics of simulation and the stereoscopic visualization in VR environment provides a more realistic and impressive interaction with virtual prototypes than in CAD environment.

The proposed methodology is fully exploited through two case studies: the choice of the optimal design for a traditional Neapolitan coffee maker, addressed by the Italian designer Riccardo Dalisi, and for a subassembly of a new minicar.     

Collaborative eScience libraries

In the context of collaborative eScience, digital libraries are one of many distributed, interoperable resources available to scientists that facilitate both human and machine collaboration: machine collaboration in the form of standards such as the Open Archives Initiative Protocol for Metadata Harvesting and human collaboration in the form of collaborative workspaces. This paper describes a set of collaborative workspaces created at the Los Alamos National Laboratory Research Library, initial patterns of use, and additional user requirements determined based on these initial patterns of use.     

Major events and urban development: exploring the spatial impact of China's expositions in the early twentieth century

ABSTRACT

Urban developments steered by major events have a long history. Already from the second half of the nineteenth century, World Expositions were mobilized as opportunities for urban upgrading. This article highlights the spatial effects of three Chinese major expositions on their host cities in the early twentieth century (1906–1929). It will in particular highlight the impact on urban development and planning, such as the construction of modern public complexes, the promotion of new urban districts, and the catalysis of structural urban transitions. Considering the significant historical, political, and social analogies, we argue in this article that expositions were adopted under the influence of foreign examples as a model of planning interventions to prompt the modernization of the host cities in China. However, while there was an important transfer of spatial concepts and models, we contend that Chinese authorities played a leading role in importing and exploiting these expositions as strategic instruments. They did so by actively and consciously mobilizing multiple urban actors such as social elites, but also civil society leaders and merchants. This article based on archival research on three expositions, provides novel insights into the urban history of the host cities during the exposition period.