Mildred S. Seelig, ’ M.D., M.P.H., and H. Alexander Heggtveit,2 M.D. Magnesium ions are essential for the main-tenance of the functional and structural integ-rity of the myocardium. Experimental mag-nesium deficiency induces cardiac necrosis and enhances susceptibility to cardiotoxic agents

Bereitstellung der hervorragenden experimentellen Bedingungen. Allen Mitgliedern des Arbeitskreises möchte ich für das ausgezeichnete Arbeitsklima und die tolle Zusammenarbeit danken. Mein besonderer Dank gilt meinen aktuellen und ehemaligen Kollegen Martin Breugst, Alexander Tishkov, Erik Bräuer

This essay looks at the historical significance of two APS classic papers that are freely available online: Pitts RF and Alexander RS. The nature of the renal tubular mechanism for acidifying the urine. Am J Physiol 144: 239–254, 1945

& The mapping of cognitive functions to neural systems is a central goal of cognitive neuroscience. On the basis of homology with lesion and physiological studies in nonhuman primates, Brodmann’s area (BA) 46/9 in the middle frontal gyrus (MFG) has been proposed as the cortical focus for both the storage as well as processing components of working memory in the human brain, but the evidence on the segregation of these components and their exact areal localization has been inconsistent. In order to study this issue and increase the temporal resolution of functional mapping, we disambiguated the storage component of working memory from sensory and motor responses by employing functional magnetic resonance imaging (fMRI) in spatial delayed-response (DR) tasks with long delay intervals and different conditions of demand. We here show that BA 46 can support a sustained mnemonic response for as long as 24 sec in a high-demand task and the signal change in this area exceeded that in the other prefrontal areas examined. Our findings support a conservation of functional architecture between human and nonhuman primate in showing that the MFG is prominently engaged in the storage of spatial information. &

We investigate how competing logics facilitate resistance to institutional change, focusing on banking professionals ’ resistance to large, national banks ’ acquisitions of smaller, local banks. Acquisitions led to new bank foundings, particularly when out-of-town banks were the acquirers and a community’s local population of bank professionals was large. We argue that the national banks ’ efforts to introduce a banking logic emphasizing efficiencies of geographic diversification triggered new forms of professional entrepreneurialism intended to preserve a community logic of banking. Contributions to a synthesis of ecological and institutional perspectives and to research on entrepreneurship and resistance to institutional change are discussed. Over the past few years, institutionalists have shifted attention away from the study of isomor-phic diffusion to develop more nuanced ap-proaches to the study of organizational variation

Improvements in the CHARMM all-atom force field for atomic-level molecular simulations of lipids are reported. Substantial adjustments have been made to the Lennard-Jones (LJ) hydrocarbon and torsional parameters and to the partial atomic charges and torsional parameters of the phosphate moiety. These changes were motivated by a combination of unexpected simulation results and recent high-level ab initio quantum mechanical calculations. The parameter optimization procedure is described, and the resulting energy function validated by an 11 ns molecular dynamics simulation of a hydrated phospholipid bilayer. Of note is the influence of the hydrocarbon LJ parameters on the conformational properties of the aliphatic tails, emphasizing the importance of obtaining the proper balance between the bonded and nonbonded portions of the force field. Compatibility with the CHARMM all-atom parameter sets for proteins and nucleic acids has been maintained such that high quality simulations of biologically interesting membranes are possible. The complete force field is included as Supporting Information and is available from www.pharmacy.umaryland.edu/alex.

■ Converging evidence from humans and nonhuman pri-mates is obliging us to abandon conventional models in favor of a radically different, distributed-network paradigm of corti-cal memory. Central to the new paradigm is the concept of memory network or cognit—that is, a memory or an item of knowledge defined by a pattern of connections between neu-ron populations associated by experience. Cognits are hi-erarchically organized in terms of semantic abstraction and complexity. Complex cognits link neurons in noncontiguous cortical areas of prefrontal and posterior association cortex. Cognits overlap and interconnect profusely, even across hier-archical levels (heterarchically), whereby a neuron can be part of many memory networks and thus many memories or items of knowledge. ■

, in the first place. The first great era in the history of the Coast Survey ended with the death of Alexander Dallas Bache in 1867. Bache, the second superintendent and successor to Ferdinand Hassler, the founder of the Survey, left an organization which had begun to realize the potential that Hassler had

Abstract. Although the Semantic Web was originally designed as a “web for machines”, the growing wealth of information in Linked Open Data has become interesting for human users as well. Consequently, quite a few browsers for Linked Open Data have recently been developed. However, despite being developed for the semantic web, those browsers often present alphabetically ordered lists of facts, without respecting the semantics of the data. In our submission to the Semantic Web Challenge, we present a semantic browser for the semantic web 1, which aims at presenting facts from Linked Open Data in semantically coherent groups. This paper introduces the main algorithms as well as an evaluation of the browser with end users.

Abstract not found