At A Crossroad: The U.S. Economy

The U.S. economy stands at a crossroad.  Which path will it take – the one that leads to sustainable growth, recession or inflation?  This paper will examine market imbalances which may indicate the future economic direction

Sub-Prime Mortgages And The Big Bang

Delinquencies and failures of sub-prime mortgages provide evidence that the housing bubble has burst.  This study traces the creation of the housing bubble and examines the impact of the sub-prime debacle on world financial markets

he Global Impact Of Chinas Currency Policy: U.S. And Beyond

Since the yuan is pegged to the dollar, the U.S. and Chinese economies have become inter-connected in a myriad of ways. This study examines the global implications of this relationship

Credit Default Swaps: The Good, The Bad And The Ugly

Credit Default Swaps have been a major cause of problems to financial institutions during the current economic downturn.  What is a CDS?  Why was it developed?  What went wrong?  This paper discusses these questions

The optical variability of the narrow line Seyfert 1 galaxy IRAS 13224-3809

We report on a short optical monitoring programme of the narrow-line Seyfert 1 Galaxy IRAS 13224-3809. Previous X-ray observations of this object have shown persistent giant variability. The degree of variability at other wavelengths may then be used to constrain the conditions and emission processes within the nucleus. Optical variability is expected if the electron population responsible for the soft X-ray emission is changing rapidly and Compton-upscattering infrared photons in the nucleus, or if the mechanism responsible for X-ray emission causes all the emission processes to vary together. We find that there is no significant optical variability with a firm upper limit of 2 per cent and conclude that the primary soft X-ray emission region produces little of the observed optical emission. The X-ray and optical emission regions must be physically distinct and any reprocessing of X-rays into the optical waveband occurs some distance from the nucleus. The lack of optical variability indicates that the energy density of infrared radiation in the nucleus is at most equal to that of the ultraviolet radiation since little is upscattered into the optical waveband. The extremely large X-ray variability of IRAS 13224-3809 may be explained by relativistic boosting of more modest variations. Although such boosting enhances X-ray variability over optical variability, this only partially explains the lack of optical variability.Comment: 5 pages with 8 postscript figures. Accepted for publication in MNRA

Systematic review of topical treatments for fungal infections of the skin and nails of the feet

OBJECTIVE: To identify and synthesise the evidence for efficacy and cost effectiveness of topical treatments for superficial fungal infections of the skin and nails of the feet. DESIGN: Systematic review. INTERVENTIONS: Topical treatments for superficial fungal infections. MAIN OUTCOME MEASURES: Cure confirmed by culture and microscopy for skin and by culture for nails in patients with clinically diagnosed fungal infections. RESULTS: Of 126 trials identified in 121 papers, 72 (57.1%) met the inclusion criteria. Placebo controlled trials yielded pooled relative risks of failure to cure skin infections: allylamines (0.30, 95% confidence interval 0.24 to 0.38); azoles (0.54, 0.42 to 0.68); undecenoic acid (0.28, 0.11 to 0.74); and tolnaftate (0.46, 0.17 to 1.22). Although meta-analysis of 11 trials comparing allylamines and azoles showed a relative risk of failure to cure of 0.88 (0.78 to 0.99) in favour of allylamines, there was evidence of language bias. Seven reports in English favoured allylamines (0.79, 0.69 to 0.91), but four reports in foreign languages showed no difference between the two drugs (1.01, 0.90 to 1.13). Neither trial of nail infections showed significant differences between alternative topical treatments. CONCLUSIONS: Allylamines, azoles, and undecenoic acid were efficacious in placebo controlled trials. There are sufficient comparative trials to judge relative efficacy only between allylamines and azoles. Allylamines cure slightly more infections than azoles but are much more expensive than azoles. The most cost effective strategy is first to treat with azoles or undecenoic acid and to use allylamines only if that fails

Danger Zones Dead Ahead For The U.S. And China: Prospects And Challenges

To be successful and remain independent, every country must create a prosperous economy, keep peace among its people, maintain political stability, and ensure the security of the people and the country from internal and external threats. Doing all four at the same time is never easy and in a time of economic volatility, change, and uncertainty juggling all four becomes more difficult.  This is when countries enter the danger zone where hidden cracks and fissures in a country’s organization and structure could become destabilizing. In this paper we will compare the challenges and prospects for the United States and China as both countries enter the danger zone.  The purpose of this paper is to examine how each country’s unique attributes are likely to impact its ability to succeed.  We will examine their political, economic and legal systems to determine the strengths and weaknesses of each.  We will also assess the role of corruption in each society. Both the United States and China have serious economic, social, political and security issues on the horizon.  To solve the problems will require serious sacrifices and pain for a large portion of the populations in both countries.  Which form of government will best be able to adapt quickly to the constantly changing environment?  Will a serious economic slowdown topple the Communist dictatorship in China?  Will gridlock and distrust in the U.S. prevent Americans from adapting fast enough to make the necessary changes in time to save its financial system and economy?  Time will tell

Effects of carbon dioxide on the searching behaviour of the root-feeding clover weevil <i>Sitona lepidus</i> (Coleoptera: Curculionidae)

The respiratory emission of CO2 from roots is frequently proposed as an attractant that allows soil-dwelling insects to locate host plant roots, but this role has recently become less certain. CO2 is emitted from many sources other than roots, so does not necessarily indicate the presence of host plants, and because of the high density of roots in the upper soil layers, spatial gradients may not always be perceptible by soil-dwelling insects. The role of CO2 in host location was investigated using the clover root weevil Sitona lepidus Gyllenhall and its host plant white clover (Trifolium repens L.) as a model system. Rhizochamber experiments showed that CO2 concentrations were approximately 1000 ppm around the roots of white clover, but significantly decreased with increasing distance from roots. In behavioural experiments, no evidence was found for any attraction by S. lepidus larvae to point emissions of CO2, regardless of emission rates. Fewer than 15% of larvae were attracted to point emissions of CO2, compared with a control response of 17%. However, fractal analysis of movement paths in constant CO2 concentrations demonstrated that searching by S. lepidus larvae significantly intensified when they experienced CO2 concentrations similar to those found around the roots of white clover (i.e. 1000 ppm). It is suggested that respiratory emissions of CO2 may act as a ‘search trigger’ for S. lepidus, whereby it induces larvae to search a smaller area more intensively, in order to detect location cues that are more specific to their host plant.<br/

Repression of CIITA by the Epstein-Barr virus transcription factor Zta is independent of its dimerization and DNA binding

Repression of the cellular CIITA gene is part of the immune evasion strategy of the γherpes virus Epstein-Barr virus (EBV) during its lytic replication cycle in B-cells. In part this is mediated through down regulation of MHC class II gene expression via the targeted repression of CIITA, the cellular master regulator of MHC class II gene expression. The repression is achieved through a reduction in CIITA promoter activity initiated by the EBV transcription and replication factor Zta (BZLF1, EB1, ZEBRA). Zta is the earliest gene expressed during the lytic replication cycle. Zta interacts with sequence specific elements in promoters, enhancers and the replication origin (ZREs) and also modulates gene expression through interaction with cellular transcription factors and co-activators. Here we explore the requirements for Zta-mediated repression of the CIITA promoter. We find that repression by Zta is specific for the CIITA promoter and can be achieved in the absence of other EBV genes. Surprisingly, we find that the dimerization region of Zta is not required to mediate repression. This contrasts with an obligate requirement of this region to correctly orientate the DNA contact regions of Zta to mediate activation of gene expression through ZREs. Additional support for the model that Zta represses the CIITA promoter without direct DNA binding comes from promoter mapping that shows that repression does not require the presence of a ZRE in the CIITA promoter