Non-Tariff Barriers as a Test of Political Economy Theories

This paper provides a rough test of a broad and prominent class of political economy of trade models and finds them wanting. The class features governments with weighted social welfare functions, including the prominent model of Grossman and Helpman. Whether the government is the single domestic player or there are other players involved (as with the lobbies in the Grossman-Helpman case) the government ultimately acts as a unitary player in international dealings. Recent work has shown that such unitary actors care exclusively about terms of trade in international negotiations. This paper pursues the implication that governments' choice of trade instruments may offer a better test of the unitary government framework than existing empirical work. We use the structure of United States protection to argue that governments consistently choose instruments that sacrifice terms of trade, thus casting doubt on the unitary approach. We offer a discussion of alternative theories of political economy that could accommodate this stylized fact.Trade policy, Lobbying, Tariffs, Political Economy

Sanctions on South Africa: What Did They Do

This paper considers the economic sanctions that were applied in the mid-1980s to pressure the South African government to end apartheid. It asks what role those sanctions played in the eventual demise of the apartheid regime and concludes that the role was probably very small. An alternative explanation for the regime change is offered: the communist bloc combined to bring about the change. If one is to argue for the efficacy of sanctions, two key obstacles are their limited economic impact and the substantial lag between the imposition of sanctions and the political change. Since sanctions preceded the change of government, it is impossible to rule them out as a determinant. However, their principal effect was probably psychological. The implication is that the South African case should not serve as the lone major instance of effective sanctions.Keywords: Sanctions, South Africa, Political Economy, Trade

Untitled: A Study of Formal and Informal Property Rights in Urban Ecuador

In this paper we explore the substitutability of formal and informal property rights. We analyze new survey data from Ecuador, where households have both formal and informal claims to urban residential property. The latter come from a variety of sources, including the activity of a local boss, or organizer. We first develop a theory of the ability to sell or rent land in which a distinction is drawn between transferable property rights (e.g., title) and non-transferable claims (e.g., length of residence). We use this theory of transactions to show that the increase in price that follows the granting of title may be an overestimate of the households' utility gain. In our empirical work we find that the unconditional effect of granting title is to raise properties' value by 23.5%. However, we also find that informal property rights can substitute effectively for formal property rights, so the marginal effect of titling on the ability to transact and on prices can vary widely among communities and among households within a community. For example, the value of property owned by a newly established household with no adult males can increase by 46% with the acquisition of title. These findings suggest that titling programs should be targeted at young disorganized communities if they are to have much effect.

Induction of Metastatic Gastric Cancer by Peroxisome Proliferator-Activated Receptorδ Activation

Peroxisome proliferator-activated receptorδ (PPARδ) regulates a multiplicity of physiological processes associated with glucose and lipid metabolism, inflammation, and proliferation. One or more of these processes likely create risk factors associated with the ability of PPARδ agonists to promote tumorigenesis in some organs. In the present study, we describe a new gastric tumor mouse model that is dependent on the potent and highly selective PPARδ agonist GW501516 following carcinogen administration. The progression of gastric tumorigenesis was rapid as determined by magnetic resonance imaging and resulted in highly metastatic squamous cell carcinomas of the forestomach within two months. Tumorigenesis was associated with gene expression signatures indicative of cell adhesion, invasion, inflammation, and metabolism. Increased PPARδ expression in tumors correlated with increased PDK1, Akt, β-catenin, and S100A9 expression. The rapid development of metastatic gastric tumors in this model will be useful for evaluating preventive and therapeutic interventions in this disease

Department of Pathology, Thomas Jefferson University, Identification of conserved gene expression features between murine mammary carcinoma models and human breast tumors.

BACKGROUND: Although numerous mouse models of breast carcinomas have been developed, we do not know the extent to which any faithfully represent clinically significant human phenotypes. To address this need, we characterized mammary tumor gene expression profiles from 13 different murine models using DNA microarrays and compared the resulting data to those from human breast tumors. RESULTS: Unsupervised hierarchical clustering analysis showed that six models (TgWAP-Myc, TgMMTV-Neu, TgMMTV-PyMT, TgWAP-Int3, TgWAP-Tag, and TgC3(1)-Tag) yielded tumors with distinctive and homogeneous expression patterns within each strain. However, in each of four other models (TgWAP-T121, TgMMTV-Wnt1, Brca1Co/Co;TgMMTV-Cre;p53+/- and DMBA-induced), tumors with a variety of histologies and expression profiles developed. In many models, similarities to human breast tumors were recognized, including proliferation and human breast tumor subtype signatures. Significantly, tumors of several models displayed characteristics of human basal-like breast tumors, including two models with induced Brca1 deficiencies. Tumors of other murine models shared features and trended towards significance of gene enrichment with human luminal tumors; however, these murine tumors lacked expression of estrogen receptor (ER) and ER-regulated genes. TgMMTV-Neu tumors did not have a significant gene overlap with the human HER2+/ER- subtype and were more similar to human luminal tumors. CONCLUSION: Many of the defining characteristics of human subtypes were conserved among the mouse models. Although no single mouse model recapitulated all the expression features of a given human subtype, these shared expression features provide a common framework for an improved integration of murine mammary tumor models with human breast tumors