Dynamic performance of squeeze-film bearings

Earlier work has shown that oil-film forces can be modelled by linear coefficients. Identification techniques were used to generate numerical values for these coefficients. This paper has shown the invalidity of applying the perturbation techniques normally used in bearing studies to derive expressions for linearized coefficients to represent a cavitated oil-film. An alternative approach was developed based upon energy techniques to obtain estimates for linearized coefficients. Some current work being undertaken suggests that an alternative analytical approach is possible. These results will be reported in due course

Non-default Component of Sovereign Emerging Market Yield Spreads and its Determinants: Evidence from Credit Default Swap Market

This article shows that a sizable component of emerging market sovereign yield spreads is due to factors other than default risk, such as liquidity. The author estimates the non-default component of the yield spreads as the basis between the actual credit default swap (CDS) premium and the hypothetical CDS premium implied by emerging market bond yields. On average, the basis is large and positive for speculative-grade bonds and slightly negative for investment-grade bonds. The large positive basis for speculative-grade bonds supports the existence of speculation in the CDS market when the underlying's credit quality is bad. The author studies the effects of bond liquidity, liquidity in the CDS market, equity market performance, and macroeconomic variables on the non-default component of the emerging market yield spreads. The results show that bond liquidity has a significant and positive effect on the CDS–bond basis of investment-grade bonds. The results suggest that the liquid bonds of investment-grade bonds are more expensive relative to the prices implied their CDS premiums. However, the results are somewhat mixed and even contrary for the speculative-grade bond sample.Emerging Market Sovereign Bonds, Credit Risk, Credit Default Swaps, Basis, Liquidity, Emerging Market Equity Markets

The Onset of Nuclear Structure Effects in Near-Barrier Elastic Scattering of Weakly-Bound Nuclei: 6^6He and 6^6Li Compared

The elastic scattering of the halo nucleus $^6$He from heavy targets at incident energies near the Coulomb barrier displays a marked deviation from the standard Fresnel-type diffraction behavior. This deviation is due to the strong Coulomb dipole breakup coupling produced by the Coulomb field of the heavy target, a specific feature of the nuclear structure of $^6$He. We have performed Continuum Discretized Coupled Channels calculations for the elastic scattering of $^{6}$He and $^6$Li from $^{58}$Ni, $^{120}$Sn, $^{144}$Sm, $^{181}$Ta and $^{208}$Pb targets in order to determine the range of $Z_{\mathrm T}$ where this nuclear-structure specific coupling effect becomes manifest. We find that the strong Coulomb dipole breakup coupling effect is only clearly experimentally distinguishable for targets of $Z_{\mathrm T} \approx 80$.Comment: 10 pages with 3 figure

Non-default Component of Sovereign Emerging Market Yield Spreads and its Determinants: Evidence from Credit Default Swap Market

This article shows that a sizable component of emerging market sovereign yield spreads is due to factors other than default risk, such as liquidity. The author estimates the non-default component of the yield spreads as the basis between the actual credit default swap (CDS) premium and the hypothetical CDS premium implied by emerging market bond yields. On average, the basis is large and positive for speculative-grade bonds and slightly negative for investment-grade bonds. The large positive basis for speculative-grade bonds supports the existence of speculation in the CDS market when the underlying's credit quality is bad. The author studies the effects of bond liquidity, liquidity in the CDS market, equity market performance, and macroeconomic variables on the non-default component of the emerging market yield spreads. The results show that bond liquidity has a significant and positive effect on the CDS–bond basis of investment-grade bonds. The results suggest that the liquid bonds of investment-grade bonds are more expensive relative to the prices implied their CDS premiums. However, the results are somewhat mixed and even contrary for the speculative-grade bond sample

Dynamic Sources of Sovereign Bond Market Liquidity

Using 482 US Dollar and Euro denominated bonds issued by 72 sovereigns, we examine the dynamic sources of time-series and cross-sectional variations in \textit{market-wide liquidity} of sovereign bonds as a novelty in the sovereign fixed income literature. Vector autoregression analysis shows that macroeconomic fundamentals and the financial market variables play a substantial role in the movements of aggregate liquidity throughout the whole sample period (1999-2010), although their effects are stronger during the financial crisis. Specifically, US industrial production growth rate and inflation rate have significant informative powers on the sovereign bond market liquidity. An increasing shock to the TED spread (the spread between 3-Month Libor and US T-bill), a measure of distrust in the banking system, has detrimental impact, while equity market performance is positively linked to market-wide bond liquidity. Furthermore, the direction of causality from the world financial and macroeconomic variables towards the aggregate bond market liquidity is confirmed by Granger causality tests. Finally, impulse response functions show that these relationships are persistent up to one-year forecast horizon

Dynamic Sources of Sovereign Bond Market Liquidity

Using 482 US Dollar and Euro denominated bonds issued by 72 sovereigns, we examine the dynamic sources of time-series and cross-sectional variations in \textit{market-wide liquidity} of sovereign bonds as a novelty in the sovereign fixed income literature. Vector autoregression analysis shows that macroeconomic fundamentals and the financial market variables play a substantial role in the movements of aggregate liquidity throughout the whole sample period (1999-2010), although their effects are stronger during the financial crisis. Specifically, US industrial production growth rate and inflation rate have significant informative powers on the sovereign bond market liquidity. An increasing shock to the TED spread (the spread between 3-Month Libor and US T-bill), a measure of distrust in the banking system, has detrimental impact, while on the other side equity market performance is positively linked to market-wide bond liquidity. Furthermore, the direction of causality from the world financial and macroeconomic variables towards the aggregate bond market liquidity is confirmed by Granger causality tests. Finally, impulse response functions show that these relationships are persistent up to one-year forecast horizon

Selective intraarterial radionuclide therapy with Yttrium-90 (Y-90) microspheres for unresectable primary and metastatic liver tumors

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to evaluate the success of selective intraarterial radionuclide therapy (SIRT) with Yttrium-90 (Y-90) microspheres in liver metastases of different tumors. We also interpreted the contribution of SIRT to survival times according to responder- non responder and hepatic- extra hepatic disease.</p> <p>Methods</p> <p>The clinical and follow-up data of 124 patients who were referred to our department for SIRT between June 2006 and October 2010 were evaluated retrospectively. SIRT has been applied to 78 patients who were suitable for treatment. All the patients had primary liver tumor or unresectable liver metastasis of different malignancies. The treatment was repeated at least one more time in 5 patients to the same or other lobes. Metabolic treatment response evaluated by fluorine-18 fluorodeoxyglucose (F18-FDG) positron emission tomography/computed tomography (PET/CT) in the 6^thweek after treatment. F18-FDG PET/CT was repeated in per six weeks periods. The response criterion had been described as at least 20% decrease of SUV value. Also in patients with neuroendocrine tumor serial Gallium-68 (Ga-68) PET/CT was used for evaluation of response. Patients were divided into 2 groups according to their treatment response.</p> <p>Results</p> <p>68 patients received treatment for the right lobe, seven patients received treatment for the left lobe and 3 patients for both lobes. The mean treatment dose was estimated at 1.62 GBq. In the evaluation of treatment response; 43(55%) patients were responder (R) and 35 (45%) patients were non-responder (NR) in the sixth week F18-FDG PET/CT. Mean pretreatment SUVmax value of R group was 11.6 and NR group was 10.7. While only 11 (31%) out of 35 NR patients had H disease, 30 (69%) out of 43 R patients had H disease (p < 0.05). The mean overall survival time of R group was calculated as 25.63 ± 1.52 months and NR group's 20.45 ± 2.11 (p = 0.04). The mean overall survival time of H group was computed as 25.66 ± 1.52 months and EH group's 20.76 ± 1.97 (p = 0.09).</p> <p>Conclusions</p> <p>SIRT is a useful treatment method which can contribute to the lengthening of survival times in patients with primary or metastatic unresectable liver malignancies. Also F18-FDG PET/CT is seen to be a successful imaging method in evaluating treatment response for predicting survival times in this patient group.</p

De novo Transcriptome Assemblies of Rana (Lithobates) catesbeiana and Xenopus laevis Tadpole Livers for Comparative Genomics without Reference Genomes

In this work we studied the liver transcriptomes of two frog species, the American bullfrog (Rana (Lithobates) catesbeiana) and the African clawed frog (Xenopus laevis). We used high throughput RNA sequencing (RNA-seq) data to assemble and annotate these transcriptomes, and compared how their baseline expression profiles change when tadpoles of the two species are exposed to thyroid hormone. We generated more than 1.5 billion RNA-seq reads in total for the two species under two conditions as treatment/control pairs. We de novo assembled these reads using Trans-ABySS to reconstruct reference transcriptomes, obtaining over 350,000 and 130,000 putative transcripts for R. catesbeiana and X. laevis, respectively. Using available genomics resources for X. laevis, we annotated over 97% of our X. laevis transcriptome contigs, demonstrating the utility and efficacy of our methodology. Leveraging this validated analysis pipeline, we also annotated the assembled R. catesbeiana transcriptome. We used the expression profiles of the annotated genes of the two species to examine the similarities and differences between the tadpole liver transcriptomes. We also compared the gene ontology terms of expressed genes to measure how the animals react to a challenge by thyroid hormone. Our study reports three main conclusions. First, de novo assembly of RNA-seq data is a powerful method for annotating and establishing transcriptomes of non-model organisms. Second, the liver transcriptomes of the two frog species, R. catesbeiana and X. laevis, show many common features, and the distribution of their gene ontology profiles are statistically indistinguishable. Third, although they broadly respond the same way to the presence of thyroid hormone in their environment, their receptor/signal transduction pathways display marked differences