Interviewing Matching in Random Markets

In many centralized labor markets candidates interview with potential employers before matches are formed through a clearinghouse One prominent example is the market for medical residencies and fellowships, which in recent years has had a large increase in the number of interviews. There have been numerous efforts to reduce the cost of interviewing in these markets using a variety of signalling mechanisms, however, the theoretical properties of these mechanisms have not been systematically studied in models with rich preferences. In this paper we give theoretical guarantees for a variety of mechanisms, finding that these mechanisms must properly balance competition. We consider a random market in which agents' latent preferences are based on observed qualities, personal taste and (ex post) interview shocks and assume that following an interview mechanism a final stable match is generated with respect to preferences over interview partners. We study a novel many-to-many interview match mechanism to coordinate interviews and that with relatively few interviews, when suitably designed, the interview match yields desirable properties. We find that under the interview matching mechanism with a limit of $k$ interviews per candidate and per position, the fraction of positions that are unfilled vanishes quickly with $k$. Moreover the ex post efficiency grows rapidly with $k$, and reporting sincere pre-interview preferences to this mechanism is an $\epsilon$-Bayes Nash equilibrium. Finally, we compare the performance of the interview match to other signalling and coordination mechanisms from the literature

Differential Metabolisms of Green Leaf Volatiles in Injured and Intact Parts of a Wounded Leaf Meet Distinct Ecophysiological Requirements

Almost all terrestrial plants produce green leaf volatiles (GLVs), consisting of six-carbon (C6) aldehydes, alcohols and their esters, after mechanical wounding. C6 aldehydes deter enemies, but C6 alcohols and esters are rather inert. In this study, we address why the ability to produce various GLVs in wounded plant tissues has been conserved in the plant kingdom. The major product in completely disrupted Arabidopsis leaf tissues was (Z)-3-hexenal, while (Z)-3-hexenol and (Z)-3-hexenyl acetate were the main products formed in the intact parts of partially wounded leaves. 13C-labeled C6 aldehydes placed on the disrupted part of a wounded leaf diffused into neighboring intact tissues and were reduced to C6 alcohols. The reduction of the aldehydes to alcohols was catalyzed by an NADPH-dependent reductase. When NADPH was supplemented to disrupted tissues, C6 aldehydes were reduced to C6 alcohols, indicating that C6 aldehydes accumulated because of insufficient NADPH. When the leaves were exposed to higher doses of C6 aldehydes, however, a substantial fraction of C6 aldehydes persisted in the leaves and damaged them, indicating potential toxicity of C6 aldehydes to the leaf cells. Thus, the production of C6 aldehydes and their differential metabolisms in wounded leaves has dual benefits. In disrupted tissues, C6 aldehydes and their α,β-unsaturated aldehyde derivatives accumulate to deter invaders. In intact cells, the aldehydes are reduced to minimize self-toxicity and allow healthy cells to survive. The metabolism of GLVs is thus efficiently designed to meet ecophysiological requirements of the microenvironments within a wounded leaf

Imagining an Imperial Modernity: Universities and the West African Roots of Colonial Development

© 2016 Informa UK Limited, trading as Taylor & Francis GroupThis article takes the formation and work of the ‘Elliot’ Commission on Higher Education in West Africa (1943–45) to reconsider the roots of British colonial development. Late colonial universities were major development projects, although they have rarely been considered as such. Focusing particularly on the Nigerian experience and the controversy over Yaba Higher College (founded 1934), the article contends that late colonial plans for universities were not produced in Britain and then exported to West African colonies. Rather, they were formed through interactions between agendas and ideas with roots in West Africa, Britain and elsewhere. These debates exhibited asymmetries of power but produced some consensus about university development. African and British actors conceptualised modern education by combining their local concerns with a variety of supra-local geographical frames for development, which included the British Empire and the individual colony. The British Empire did not in this case forestall development, but shaped the ways in which development was conceived

Distinct cellular pathways select germline-encoded and somatically mutated antibodies into immunological memory

One component of memory in the antibody system is long-lived memory B cells selected for the expression of somatically mutated, high-affinity antibodies in the T cell–dependent germinal center (GC) reaction. A puzzling observation has been that the memory B cell compartment also contains cells expressing unmutated, low-affinity antibodies. Using conditional Bcl6 ablation, we demonstrate that these cells are generated through proliferative expansion early after immunization in a T cell–dependent but GC-independent manner. They soon become resting and long-lived and display a novel distinct gene expression signature which distinguishes memory B cells from other classes of B cells. GC-independent memory B cells are later joined by somatically mutated GC descendants at roughly equal proportions and these two types of memory cells efficiently generate adoptive secondary antibody responses. Deletion of T follicular helper (Tfh) cells significantly reduces the generation of mutated, but not unmutated, memory cells early on in the response. Thus, B cell memory is generated along two fundamentally distinct cellular differentiation pathways. One pathway is dedicated to the generation of high-affinity somatic antibody mutants, whereas the other preserves germ line antibody specificities and may prepare the organism for rapid responses to antigenic variants of the invading pathogen