New Shape (new + shape)

Distribution by Scientific Domains

Selected Abstracts

New shapes to shift: war, parks and the hunting person in modern West Africa

Melissa Leach
The deployment of Mande hunters' brotherhoods in environmental defence around Guinea's national parks, and in civil defence in Sierra Leone's war, represent two cases where international and fragmented state interests are interlocking transformatively with ,traditional' organizations in modern West Africa. Emphasizing the embeddedness of hunting in ideas and practices linking social and ecological processes, this article explores how the construction and representation of gender and authority domains are negotiated in articulation with larger political-economic processes in these two cases. Important parallels and interconnections include the ambiguous basis of hunters' identity, distinctiveness, and sociality in the region; the reproduction of both hierarchies and ambiguities in gender relations; potent linkages between environmental protection and conflict, and the ways apparently technocratic or peace-building initiatives can serve to fuel oppositional politics and the creation of armed ethnic regionalisms. [source]

Polymers Move in Response to Light

Y. Jiang
Abstract Significant advances have recently been made in the development of functional polymers that are able to undergo light-induced shape changes. The main challenge in the development of such polymer systems is the conversion of photoinduced effects at the molecular level to macroscopic movement of working pieces. This article highlights some selected polymer architectures and their tailored functionalization processes. Examples include the contraction and bending of azobenzene-containing liquid-crystal elastomers and volume changes in gels. We focus especially on light-induced shape-memory polymers. These materials can be deformed and temporarily fixed in a new shape. They only recover their original, permanent shape when irradiated with light of appropriate wavelengths. Using light as a trigger for the shape-memory effect will extend the applications of shape-memory polymers, especially in the field of medical devices where triggers other than heat are highly desirable. [source]

Professor Ludwig M. Lachmann (1906-1990): Scholar, Teacher, and Austrian School Critic of Late Classical Formalism in Economics

Stephan Boehm
Ludwig M. Lachmann was born in Berlin in 1906 and died in Johannesburg in 1990. For more than forty years, until his retirement in 1972, Lachmann established himself as a prominent South African economist and for a time served as head of the economics department at the University of Witwatersrand. From 1974 to 1987, he worked with Professor Israel Kirzner in New York City to give new shape and life to the older Austrian school of economics. Lachmann influenced a small army of modern Austrians to discard the elaborate formalisms of orthodox economics for a "radical subjectivism" that had its roots in the teachings of the founder of the Austrian school, Carl Menger. Here a small platoon of scholars offer their thoughts about Lachmann, his contributions to economic reasoning, and his eccentric but engaging character. First hand reports explain what their mentor taught and what his students took away. Lavoie makes the case that Lachmann's "radical subjectivism" took a rhetorical turn toward the end of Lachmann's career in New York City. In addition, Kirzner reports on his long and most productive relationship with Lachmann and provides additional insights about the seminal role of the Austrian Economics Seminar at New York University from 1985 to 1987 in giving shape to the modern Austrian revival. This article is the written version of a "Remembrance and Appreciation Session" held on June 28, 1999 at the History of Economics Society meeting at the University of North Carolina in Greensboro. It is one of an ongoing series that appears in the July issues of this journal. [source]

Coding repeats and evolutionary "agility"

BIOESSAYS, Issue 6 2005
Sandrine Caburet
The rapid generation of new shapes observed in the living world is the result of genetic variation, especially in "morphological" developmental genes. Many of these genes contain coding tandem repeats. Fondon and Garner have shown that expansions and contractions of these repeats are associated with the great diversity of morphologies observed in the domestic dog, Canis familiaris.1 In particular, they found that the repeat variations in two genes were significantly associated with changes in limb and skull morphology. These results open the possibility that such a mechanism contributes to the diversity of life. BioEssays 27:581,587, 2005. 2005 Wiley Periodicals, Inc. [source]

Rational shape engineering of the filamentous protein , prefoldin through incremental gene truncation

BIOPOLYMERS, Issue 6 2009
Timothy A. Whitehead
Abstract An enticing possibility in nanotechnology is to use proteins as templates for the positioning of molecules in regular patterns with nanometer precision over large surface areas. However, the ability to redesign protein quaternary structure to construct new shapes remains underdeveloped. In the present work, we have engineered the dimensions of a filamentous protein, the , prefoldin (, PFD) from the hyperthermophile Methanocaldococcus jannaschii, and have achieved controllable attachment of filaments in a specific orientation on a carbon surface. Four different constructs of , PFD were generated in which the coiled coils extending from the association domain are progressively truncated. Three of the truncation constructs form well-defined filaments with predictable dimensions according to transmission electron microscopy. Two of these constructs had 2D persistence lengths similar to that of , PFD at 300,740 nm. In contrast, the 2D persistence length of the shortest truncation mutant was 3500 nm, indicating that the filament adsorbs along a different axis than the other constructs with its two rows of coiled coils facing out from the surface. The elastic moduli of the filaments range from 0.7,2.1 GPa, similar to rigid plastics and within the lower limit for proteins whose primary intermolecular interaction is hydrogen bonding. These results demonstrate a versatile approach for controlling the overall dimensions and surface orientation of protein filaments, and expand the toolbox by which to tune two overall dimensions in protein space for the creation of templated materials over a wide variety of conditions. 2009 Wiley Periodicals, Inc. Biopolymers 91: 496,503, 2009. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at [source]