Of the 600+ known proteases identified to date in mammals, a significant percentage is involved or implicated in pathogenic and cancer processes. The dipeptidyl peptidase IV (DPIV) gene family, comprising four enzyme members [DPIV (EC 3.4.14.5), fibroblast activation protein, DP8 and DP9] and two nonenzyme members [DP6 (DPL1) and DP10 (DPL2)], are interesting in this regard because of their multiple diverse functions, varying patterns of distribution/localization and subtle, but significant, differences in structure/substrate recognition. In addition, their engagement in cell biological processes involves both enzymatic and nonenzymatic capabilities. This article examines, in detail, our current understanding of the biological involvement of this unique enzyme family and their overall potential as therapeutic targets.

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Vitamin A deficiency is a major health problem in Africa and in many other developing countries. Biofortified staple crops that are high in pro vitamins A and adapted to local growing environment have the potential to reduce the prevalence of vitamin A deficiency. One such example is the orange-fleshed sweetpotato. However because of its distinctive orange color, which is in contrast to the white varieties that are typically consumed in Africa, it is important to assess whether consumers will accept it. It is this question that this paper attempts to address, using a choice experiment with the real product to quantify the magnitude of the premium or discount in consumers' willingness to pay that may be associated with it. In addition, it also considers the extent to which the provision of nutrition information affects valuations. Finally, it addresses whether the use of hypothetical scenarios, both with and without a cheap talk script is justified in a developing country context, and quantifies the magnitude of hypothetical bias that results as a consequence. The experiment was conducted in Uganda, which is a key target country for the dissemination of orange-fleshed sweetpotato. Our results suggest that in the absence of nutrition information, there is no difference in the willingness to pay between white and orange varieties, but there is a discount for yellow sweetpotato (which does not have any beta-carotene). The provision of nutrition information does translate into substantial premia for the orange varieties, indicating that an information campaign may be key to drive market acceptance of the new product. Finally, there is a substantial hypothetical bias in both the WTP and the marginal WTP for the new varieties, and while cheap talk mitigates this bias, it does not eliminate it.

Hunger during pre-harvest lean seasons is widespread in the agrarian areas of Asia and Sub-Saharan Africa. We randomly assign an $8.50 incentive to households in rural Bangladesh to temporarily out-migrate during the lean season. The incentive induces 22% of households to send a seasonal migrant, their consumption at the origin increases significantly, and treated households are 8-10 percentage points more likely to re-migrate 1 and 3 years after the incentive is removed. These facts can be explained qualitatively by a model in which migration is risky, mitigating risk requires individual-specific learning, and some migrants are sufficiently close to subsistence that failed migration is very costly. We document evidence consistent with this model using heterogeneity analysis and additional experimental variation, but calibrations with forward-looking households that can save up to migrate suggest that it is difficult for the model to quantitatively match the data. We conclude with extensions to the model that could provide a better quantitative accounting of the behavior.

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The protease fibroblast activation protein (FAP) is a specific marker of activated mesenchymal cells in tumour stroma and fibrotic liver. A specific, reliable FAP enzyme assay has been lacking. FAP's unique and restricted cleavage of the post proline bond was exploited to generate a new specific substrate to quantify FAP enzyme activity. This sensitive assay detected no FAP activity in any tissue or fluid of FAP gene knockout mice, thus confirming assay specificity. Circulating FAP activity was ∼20- and 1.3-fold less in baboon than in mouse and human plasma, respectively. Serum and plasma contained comparable FAP activity. In mice, the highest levels of FAP activity were in uterus, pancreas, submaxillary gland and skin, whereas the lowest levels were in brain, prostate, leukocytes and testis. Baboon organs high in FAP activity included skin, epididymis, bladder, colon, adipose tissue, nerve and tongue. FAP activity was greatly elevated in tumours and associated lymph nodes and in fungal-infected skin of unhealthy baboons. FAP activity was 14- to 18-fold greater in cirrhotic than in non-diseased human liver, and circulating FAP activity was almost doubled in alcoholic cirrhosis. Parallel DPP4 measurements concorded with the literature, except for the novel finding of high DPP4 activity in bile. The new FAP enzyme assay is the first to be thoroughly characterised and shows that FAP activity is measurable in most organs and at high levels in some. This new assay is a robust tool for specific quantitation of FAP enzyme activity in both preclinical and clinical samples, particularly liver fibrosis.

Aggregate indices like UNDP's Human Development Index (HDI) or the Centre for Global Development and Foreign Policy's Commitment to Development Index (CDI) are subject to multiple criticisms. This paper addresses concerns linked to the equal weights used in the HDI and the CDI and evaluates alternative weighting schemes. It relies on an opinion survey conducted electronically among researchers from 60 countries to assess whether or not professional judgment affects the use of equal weights. Results of the opinion survey point to a surprising result for the HDI: despite widespread criticism of equal weights, a simple scheme based on equal weights is not only convenient but also consistent with the views of experts. For some components of the CDI, however, weights derived from the survey do differ from equal weights. Nevertheless, the weights emerging from the survey are not sufficiently different from equal weights to significantly alter country rankings.

for comments. This RCT was registered in the American Economic Association Registry for randomized control trials under Trial number 2507 The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research. At least one co-author has disclosed a financial relationship of potential relevance for this research. Further information is available online at http://www.nber.org/papers/w23929.ack NBER working papers are circulated for discussion and comment purposes. They have not been peer-reviewed or been subject to the review by the NBER Board of Directors that accompanies official NBER publications.