Stuck on Gold: Real Exchange Rate Volatility and the Rise and Fall of the Gold Standard

Did adoption of the gold standard exacerbate or diminish macroeconomic volatility? Supporters thought so, critics thought not, and theory offers ambiguous messages. A hard exchange-rate regime such as the gold standard might limit monetary shocks if it ties the hands of policy makers. But any decision to forsake exchange-rate flexibility might compromise shock absorption in a world of real shocks and nominal stickiness. A simple model shows how a lack of flexibility can be discerned in the transmission of terms of trade shocks. Evidence on the relationship between real exchange rate volatility and terms of trade volatility from the late nineteenth and early twentieth century exposes a dramatic change. The classical gold standard did absorb shocks, but the interwar gold standard did not, and this historical pattern suggests that the interwar gold standard was a poor regime choice.

Stuck on gold: real exchange rate volatility and the rise and fall of the gold standard, 1870-1939

Did adoption of the gold standard exacerbate or diminish macroeconomic volatility? Supporters thought so, critics thought not, and theory offers ambiguous messages. A hard exchange-rate regime such as the gold standard might limit monetary shocks if it ties the hands of policy makers. But any decision to forsake exchange-rate flexibility might compromise shock absorption in a world of real shocks and nominal stickiness. A simple model shows how a lack of flexibility can be discerned in the transmission of terms of trade shocks. Evidence on the relationship between real exchange rate volatility and terms of trade volatility from the late nineteenth and early twentieth century exposes a dramatic change. The classical gold standard did absorb shocks, but the interwar gold standard did not, and this historical pattern suggests that the interwar gold standard was a poor regime choice

Children's Perception of Speech Produced in a Two-Talker Background

This study evaluated the degree to which children benefit from the acoustic modifications made by talkers when they produce speech in noise

Oral melanoacanthoma and oral melanotic macule : a report of 8 cases, review of the literature, and immunohistochemical analysis

Oral melanoacanthoma (MA) is a rare, benign pigmented lesion, similar to cutaneous MA, characterized by hyperplasia of spinous keratinocytes and dendritic melanocytes. The pathogenesis of oral MA remains uncertain, although its clinical behavior is suggestive of a reactive origin. The most common intraoral sites are the buccal mucosa, lip, palate and gingiva. The average age of presentation is 28 years, mainly in blacks, with a strong female predilection. The oral melanotic macule (MM) is a small, well-circumscribed brown-to-black macule that occurs on the lips and mucous membranes. The etiology is not clear and it may represent a physiologic or reactive process. The average age of presentation is 43 years, with a female predilection. A biopsy is recommended to distinguish these lesions from each other and from other oral melanocytic lesions. We depict four cases each of oral MA and MM, affecting Caucasian and Latin American mestizo patients. The clinicopathological features of these cases reflect its ample spectrum, and to the best of our knowledge, it is the first example of oral MA affecting a Caucasian boy reported in the English literature. Therefore oral MA and MM should be considered in the differential diagnosis of pigmented lesions in the oral mucosa in these populations

Recombinase-based conditional and reversible gene regulation via XTR alleles

Synthetic biological tools that enable precise regulation of gene function within in vivo systems have enormous potential to discern gene function in diverse physiological settings. Here we report the development and characterization of a synthetic gene switch that, when targeted in the mouse germline, enables conditional inactivation, reports gene expression and allows inducible restoration of the targeted gene. Gene inactivation and reporter expression is achieved through Cre-mediated stable inversion of an integrated gene-trap reporter, whereas inducible gene restoration is afforded by Flp-dependent deletion of the inverted gene trap. We validate our approach by targeting the p53 and Rb genes and establishing cell line and in vivo cancer model systems, to study the impact of p53 or Rb inactivation and restoration. We term this allele system XTR, to denote each of the allelic states and the associated expression patterns of the targeted gene: eXpressed (XTR), Trapped (TR) and Restored (R)

Comparative expression of cyclooxygenase 2 and Ki67 in amelanotic and conventional oral melanomas

Oral melanomas have some histopathological resemblance with its cutaneous counterpart; however, an aggressive behavior is more common in tumors that occur in the oral cavity. Several markers have been suggested as indicative of tumoral progression and aggressiveness, such as cyclooxygenase 2 (COX-2) and Ki67. In this study, we have compared the expression of COX-2 and Ki67 in a series of amelanotic (n=7) and melanotic oral melanomas (n=22). The cases were selected from 4 pathology laboratories and submitted to the immunohistochemical (IHC) reactions. We analyzed the IHC staining based on a qualitative ? using visual scores; and a computer-assisted method (quantitative) using scanned slides and software for digital analysis. COX-2 was expressed in all oral melanomas; however, its intensity was significantly higher in the amelanotic ones (P<0.001). Similarly, a high Ki67-positivity index was observed in the amelanotic than melanotic ones (P<0.001). Based on these results, we suggest that amelanotic oral melanomas have marked pro-inflammatory and high-proliferative phenotype, justifying their more aggressive behavior compared with the melanotic ones

Stage-specific sensitivity to p53 restoration during lung cancer progression

2011 May 25Tumorigenesis is a multistep process that results from the sequential accumulation of mutations in key oncogene and tumour suppressor pathways. Personalized cancer therapy that is based on targeting these underlying genetic abnormalities presupposes that sustained inactivation of tumour suppressors and activation of oncogenes is essential in advanced cancers. Mutations in the p53 tumour-suppressor pathway are common in human cancer and significant efforts towards pharmaceutical reactivation of defective p53 pathways are underway1, 2, 3. Here we show that restoration of p53 in established murine lung tumours leads to significant but incomplete tumour cell loss specifically in malignant adenocarcinomas, but not in adenomas. We define amplification of MAPK signalling as a critical determinant of malignant progression and also a stimulator of Arf tumour-suppressor expression. The response to p53 restoration in this context is critically dependent on the expression of Arf. We propose that p53 not only limits malignant progression by suppressing the acquisition of alterations that lead to tumour progression, but also, in the context of p53 restoration, responds to increased oncogenic signalling to mediate tumour regression. Our observations also underscore that the p53 pathway is not engaged by low levels of oncogene activity that are sufficient for early stages of lung tumour development. These data suggest that restoration of pathways important in tumour progression, as opposed to initiation, may lead to incomplete tumour regression due to the stage-heterogeneity of tumour cell populations.National Cancer Institute (U.S.) (Cancer Center Support Grant P30-CA14051)American Cancer Society (New England Area Fellow)Leukemia & Lymphoma Society of America (Fellow)Massachusetts Institute of Technology. Undergraduate Research Program (John Reed Fund)Damon Runyon Cancer Research Foundation (Merck Fellow)Genentech, Inc. (Postdoctoral Fellow)Howard Hughes Medical Institut

Geography, policy, or productivity? Regional trade in five South American countries, 1910-50

Regional trade in South America since independence has long been much smaller than would be expected if geography were the only constraint on trade. Several potential explanations exist, including low technological and demand complementarities; low productivity; and high natural and policy barriers to trade. Focusing on the latter explanations, policy makers have long advocated a South American/Southern Cone Free Trade Area¿proposed as early as 1889. Would reductions in trade costs have been sufficient to raise trade significantly, or was trade low for other reasons? We study bilateral trade between 1910 and 1950, when large external shocks altered global supply and demand. These shocks help us show that intra-regional trade could have been boosted by reductions in trade costs. Trade among Argentina, Bolivia, Brazil, Chile, and Peru could have benefited from more benign trade policies or better infrastructure. Regional trade in textiles, which took off from the 1930s, supports our argument that trade improved when trade costs fell

Analysis of the interaction with the hepatitis C virus mRNA reveals an alternative mode of RNA recognition by the human La protein

Human La protein is an essential factor in the biology of both coding and non-coding RNAs. In the nucleus, La binds primarily to 3′ oligoU containing RNAs, while in the cytoplasm La interacts with an array of different mRNAs lacking a 3′ UUUOH trailer. An example of the latter is the binding of La to the IRES domain IV of the hepatitis C virus (HCV) RNA, which is associated with viral translation stimulation. By systematic biophysical investigations, we have found that La binds to domain IV using an RNA recognition that is quite distinct from its mode of binding to RNAs with a 3′ UUUOH trailer: although the La motif and first RNA recognition motif (RRM1) are sufficient for high-affinity binding to 3′ oligoU, recognition of HCV domain IV requires the La motif and RRM1 to work in concert with the atypical RRM2 which has not previously been shown to have a significant role in RNA binding. This new mode of binding does not appear sequence specific, but recognizes structural features of the RNA, in particular a double-stranded stem flanked by single-stranded extensions. These findings pave the way for a better understanding of the role of La in viral translation initiation