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The "Asian Crisis" of 1997-98 affected all the "emerging markets" open to capital flows. Measures of corporate governance, particularly the effectiveness of protection for minority shareholders, explain the extent of depreciation and stock market decline better than do standard macroeconomic measures. A possible explanation is that in countries with weak corporate governance, worse economic prospects result in more expropriation by managers and thus a larger fall in asset prices.

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The vacuole/lysosome serves an important recycling function during starvation and senescence in eukaryotes via a process called autophagy. Here bulk cytosolic constituents and organelles become sequestered in specialized autophagic vesicles, which then deliver their cargo to the vacuole for degradation. In yeasts, genetic screens have identified two novel post-translational modification pathways remarkably similar to ubiquitination that are required for autophagy. From searches of the Arabidopsis genome, we have identified gene families encoding proteins related to both the APG8 and ؊12 polypeptide tags and orthologs for all components required for their attachment. A single APG7 gene encodes the ATP-dependent activating enzyme that initiates both conjugation pathways. Phenotypic analysis of an APG7 disruption indicates that it is not essential for normal growth and development in Arabidopsis. However, the apg7-1 mutant is hypersensitive to nutrient limiting conditions and displays premature leaf senescence. mRNAs for both APG7 and APG8 preferentially accumulate as leaves senesce, suggesting that both conjugation pathways are up-regulated during the senescence syndrome. These findings show that the APG8/12 conjugation pathways have been conserved in plants and may have important roles in autophagic recycling, especially during situations that require substantial nitrogen and carbon mobilization.Plants, like other organisms, have developed sophisticated mechanisms for recycling intracellular constituents during periods of growth, developmental remodeling, and nutrient-limiting conditions (1, 2). Especially critical is the degradation of protein, given the importance of reused amino acids to the nitrogen and carbon economy. Selective protein removal is accomplished primarily by the ubiquitin (Ub) 1 /26 S proteasome pathway (3, 4). In this pathway, the covalent attachment of Ubs is used as a signal to target specific proteins for degradation by the 26 S proteasome. Another major recycling system employs the vacuole, or its animal equivalent, the lysosome, as a lytic organelle (5, 6). Here cytosolic proteins are delivered to the vacuole and then degraded by a wide variety of vacuolar proteases. In some situations, entire organelles can be targets (7). Unlike the Ub/26 S proteasome pathway, vacuolar proteolysis is for the most part non-selective, thus targeting proteins indiscriminately. As a consequence protein turnover by the vacuole is thought to play less of a role in cellular regulation and a more prominent role under conditions when rapid remobilization and resorption of nutrients are crucial. These conditions include nutrient deprivation and environmental stress and developmental periods that require extensive cell and organ remodeling such as senescence and programmed cell death (5, 6).The vacuole degrades cytoplasm by three unique but overlapping mechanisms, chaperone-assisted import, microautophagy, and macroautophagy (6 -9). Chaperone-assisted import is activated during starvation; it employs Hsp70-related...

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We consider the problems of societal norms for cooperation and reputation when it is possible to obtain cheap pseudonyms, something that is becoming quite common in a wide variety of interactions on the Internet. This introduces opportunities to misbehave without paying reputational consequences. A large degree of cooperation can still emerge, through a convention in which newcomers "pay their dues" by accepting poor treatment from players who have established positive reputations. One might hope for an open society where newcomers are treated well, but there is an inherent social cost in making the spread of reputations optional. We prove that no equilibrium can sustain significantly more cooperation than the dues-paying equilibrium in a repeated random matching game with a large number of players in which players have finite lives and the ability to change their identities, and there is a small but nonvanishing probability of mistakes. Although one could remove the inefficiency of mistreating newcomers by disallowing anonymity, this is not practical or desirable in a wide variety of transactions. We discuss the use of entry fees, which permits newcomers to be trusted but excludes some players with low payoffs, thus introducing a different inefficiency. We also discuss the use of free but unreplaceable pseudonyms, and describe a mechanism that implements them using standard encryption techniques, which could be practically implemented in electronic transactions.

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The existence of explosive phase transitions in random (Erdős Rényi-type) networks has been recently documented by Achlioptas et al. [Science 323, 1453[Science 323, (2009] via simulations. In this Letter we describe the underlying mechanism behind these first-order phase transitions and develop tools that allow us to identify (and predict) when a random network will exhibit an explosive transition. Several interesting new models displaying explosive transitions are also presented. PACS numbers: Valid PACS appear hereThe structure and dynamics of networked models and their application to social networks is an important and active area of research encompassing many fields ranging from physics [1, 2, 3] to sociology [4] to combinations thereof [5,6,7]. Ideas from statistical mechanics have contributed greatly to our understanding of such networks and their practical uses [8,9,10]. Of particular importance is the statistical mechanical notion of the order of a phase ('percolation') transition. Phase transitions in random network models are almost always second order [11,12] or higher [12,13]. Thus, it was surprising to many when Achlioptas et al. [14] reported recently that some models of interest in social networks can display first-order (discontinuous) transitions.In that work, they described several random graph models of the Erdős Rényi (ER) variety that exhibit firstorder or what they call "explosive" phase transitions. They provide convincing numerical evidence and a useful characterization of such transitions, but no details on the mechanisms underlying them. They describe several systems which display such transitions and a general class of systems which don't.In this paper we describe the underlying mechanisms behind explosive transitions in ER-type models. We show that, somewhat surprisingly, the key to explosive transitions is not the details of the edge-addition rules at work during the actual "explosion," but rather lies in the period preceding the explosion when a type of "powder keg" develops. In effect, the importance of the rules is to create an explosive situation, which can be detonated with almost any rule. In addition, our analysis provides an understanding of which random network models will have such transitions. This allows us to construct large classes of interesting models that display this behavior. (It also allows us to rule out many other models which will not display explosive transitions.)The prototypical network percolation example is that of pure (non-preferential) ER random graphs [11]. These begin with a set of n nodes, where n is large. Edges are then added to the graph, uniformly at random. As is well known, this system exhibits a phase transition as the number of edges τ increases. For τ < 0.5n all clusters are small (∼ log(n)) while for τ > 0.5n a large cluster (∼ n) appears. In the large-n limit this transition is a secondorder phase transition, i.e., letting s(τ ) be the size of the largest cluster after τ edges have been added, the graph of s(τ )/n against τ /n is continu...