Uncertainty, Price Stabilization, and Welfare

This paper investigates whether a small country facing foreign price instability benefits from active stabilization of the domestic price of the importable. For example, the European Community can be treated as a small open economy facing price instability of agricultural products originating in the United States. A tariff is out of the question because it is not optimal for a small open economy. However, the European Community may stabilize the domestic price of the importable. It is shown that, if the random tariff revenue ex post, domestic price stabilization increases income instability and nonintervention is optimal. If an ex ante rebating scheme is employed, a small country can benefit from domestic price stabilization and there exists a partial stabilization policy that dominates free trade. Partial stabilization of the domestic price with the ex ante rebate requires a variable import levy inversely related to the foreign price of the importable. However, complete stabilization of domestic price, which requires setting a target price and a variable import levy as currently used in the European Community, is not optimal

Demand Uncertainty and Price Stabilization

Price stabilization is an important policy goal of government intervention in competitive markets. These policies are primarily directed at raising producer income and stabilizing market prices at levels acceptable to consumers and producers (Fox 1956, Turnovsky 1978, Newbery and Stiglitz 1979). Many of the stabilization policy results have been developed from the study of agricultural commodity markets. In these markets, prices tend to be highly variable due to uncertain and inelastic supply and demand (Schultz 1945, Gardner 1981)

BAC-FISH assays delineate complex chromosomal rearrangements in a case of post-Chernobyl childhood thyroid cancer

Structural chromosome aberrations are known hallmarks of many solid tumors. In the papillary form of thyroid cancer (PTC), for example, activation of the receptor tyrosine kinase (RTK) genes, RET and neurotrophic tyrosine kinase receptor type I (NTRK1) by intra- and interchromosomal rearrangements has been suggested as a cause of the disease. However, many phenotypically similar tumors do not carry an activated RET or NTRK-1 gene or express abnormal ret or NTRK- 1 transcripts. Thus, we hypothesize that other cellular RTK-type genes are aberrantly expressed in these tumors. Using fluorescence in situ hybridization-based methods, we are studying karyotype changes in a relatively rare subgroup of PTCs, i.e., tumors that arose in children following the 1986 nuclear accident in Chernobyl, Ukraine. Here, we report our technical developments and progress in deciphering complex chromosome aberrations in case S48TK, an aggressively growing PTC cell line, which shows an unusual high number of unbalanced translocations

CMS Pixel Telescope Addition to T-980 Bent Crystal Collimation Experiment at the Tevatron

An enhancement to the T-980 bent crystal collimation experiment at the Tevatron has been completed. The enhancement was the installation of a pixel telescope inside the vacuum-sealed beam pipe of the Tevatron. The telescope is comprised of six CMS PSI46 pixel plaquettes, arranged as three stations of horizontal and vertical planes, with the CAPTAN system for data acquisition and control. The purpose of the pixel telescope is to measure beam profiles produced by bent crystals under various conditions. The telescope electronics inside the beam pipe initially were not adequately shielded from the image current of the passing beams. A new shielding approach was devised and installed, which resolved the problem. The noise issues encountered and the mitigating techniques are presented herein, as well as some preliminary results from the telescope.Comment: 9 pp. 2nd International Conference on Technology and Instrumentation in Particle Physics 2011: TIPP 2011. 9-14 Jun 2011. Chicago, Illinoi

Rapid mapping of chromosomal breakpoints: from blood to BAC in 20 days

Structural chromosome aberrations and associated segmental or chromosomal aneusomies are major causes of reproductive failure in humans. Despite the fact that carriers of reciprocal balanced translocation often have no other clinical symptoms or disease, impaired chromosome homologue pairing in meiosis and karyokinesis errors lead to over-representation of translocations carriers in the infertile population and in recurrent pregnancy loss patients. At present, clinicians have no means to select healthy germ cells or balanced zygotes in vivo, but in vitro fertilization (IVF) followed by preimplantation genetic diagnosis (PGD) offers translocation carriers a chance to select balanced or normal embryos for transfer. Although a combination of telomeric and centromeric probes can differentiate embryos that are unbalanced from normal or unbalanced ones, a seemingly random position of breakpoints in these IVF-patients poses a serious obstacle to differentiating between normal and balanced embryos, which for most translocation couples, is desirable. Using a carrier with reciprocal translocation t(4;13) as an example, we describe our state-of-the-art approach to the preparation of patient-specific DNA probes that span or 'extent' the breakpoints. With the techniques and resources described here, most breakpoints can be accurately mapped in a matter of days using carrier lymphocytes, and a few extra days are allowed for PGD-probe optimization. The optimized probes will then be suitable for interphase cell analysis, a prerequisite for PGD since blastomeres are biopsied from normally growing day 3 – embryos regardless of their position in the mitotic cell cycle. Furthermore, routine application of these rapid methods should make PGD even more affordable for translocation carriers enrolled in IVF programs

Gene expression profiles in developing nephrons using Lim1 metanephric mesenchyme-specific conditional mutant mice

BACKGROUND: Lim1 is a homeobox gene that is essential for nephrogenesis. During metanephric kidney development, Lim1 is expressed in the nephric duct, ureteric buds, and the induced metanephric mesenchyme. Conditional ablation of Lim1 in the metanephric mesenchyme blocks the formation of nephrons at the nephric vesicle stage, leading to the production of small, non-functional kidneys that lack nephrons. METHODS: In the present study, we used Affymetrix probe arrays to screen for nephron-specific genes by comparing the expression profiles of control and Lim1 conditional mutant kidneys. Kidneys from two developmental stages, embryonic day 14.5 (E14.5) and 18.5 (E18.5), were examined. RESULTS: Comparison of E18.5 kidney expression profiles generated a list of 465 nephron-specific gene candidates that showed a more than 2-fold increase in their expression level in control kidney versus the Lim1 conditional mutant kidney. Computational analysis confirmed that this screen enriched for kidney-specific genes. Furthermore, at least twenty-eight of the top fifty (56%) candidates (or their vertebrate orthologs) were previously reported to have a nephron-specific expression pattern. Our analysis of E14.5 expression data yielded 41 candidate genes that are up-regulated in the control kidneys compared to the conditional mutants. Three of them are related to the Notch signaling pathway that is known to be important in cell fate determination and nephron patterning. CONCLUSION: Therefore, we demonstrate that Lim1 conditional mutant kidneys serve as a novel tissue source for comprehensive expression studies and provide a means to identify nephron-specific genes

Metallic 1T Phase, 3d1 Electronic Configuration and Charge Density Wave Order in Molecular Beam Epitaxy Grown Monolayer Vanadium Ditelluride.

We present a combined experimental and theoretical study of monolayer vanadium ditelluride, VTe2, grown on highly oriented pyrolytic graphite by molecular-beam epitaxy. Using various in situ microscopic and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X-ray and angle-resolved photoemission, and X-ray absorption, together with theoretical analysis by density functional theory calculations, we demonstrate direct evidence of the metallic 1T phase and 3d1 electronic configuration in monolayer VTe2 that also features a (4 × 4) charge density wave order at low temperatures. In contrast to previous theoretical predictions, our element-specific characterization by X-ray magnetic circular dichroism rules out a ferromagnetic order intrinsic to the monolayer. Our findings provide essential knowledge necessary for understanding this interesting yet less explored metallic monolayer in the emerging family of van der Waals magnets