Cracking the Conundrum

From 2004 to 2006, the FOMC raised the target federal funds rate by 4.25%, yet long-maturity yields and forward rates fell. We consider several possible explanations for this "conundrum." The most likely, in our view, is a fall in the term premium, probably associated with some combination of diminished macroeconomic and financial market volatility, more predictable monetary policy, and the state of the business cycle.

The use of isotopic carbon in a study of the metabolism of anthanilic acid in Neurospora

The finding by Tatum, Banner, and Beadle (l), that the tryptophanless Neurospora mutant strain 10575 accumulates anthranilic acid, which in turn can be utilized for growth of strain 40008, has provided evidence that anthranilic acid is a biochemical precursor of tryptophan in this organism. It has been further established that indole is an intermediate in this conversion (2-5). More recent work with a number of mutants of Neurospora (6-8) has established that tryptophan is a biochemical precursor to niacin with kynurenine and hydroxyanthranilic acid as intermediates. The accumulated evidence has indicated the existence in the mold of the following series of reactions: → Anthranilic acid → indole → tryptophan → kynurenine → 3-hydroxyanthranilic acid → nicotinic acid In the light of this evidence the present work was undertaken to trace the carbon in the carboxyl group of anthranilic acid in order to estimate its contribution as a structural unit in the formation of niacin and tryptophan. The organism chosen for this investigation was a biochemical mutant strain of Neurospora designated as strain 40008. This mutant utilizes anthranilic acid, indole, or tryptophan for growth. The mutant was grown in the presence of anthranilic acid containing Cl4 in the carboxyl group. Niacin and tryptophan were isolated from the mold mycelium and tested for radioactivity

Modeling river delta formation

A new model to simulate the time evolution of river delta formation process is presented. It is based on the continuity equation for water and sediment flow and a phenomenological sedimentation/ erosion law. Different delta types are reproduced using different parameters and erosion rules. The structures of the calculated patterns are analyzed in space and time and compared with real data patterns. Furthermore our model is capable to simulate the rich dynamics related to the switching of the mouth of the river delta. The simulation results are then compared with geological records for the Mississippi river

Better together? A hospitality case for umbrella branding

While the topic of ‘umbrella branding’ (UB) strategies for manufacturers' products in the business-to business literature has received attention, much less has been written about UB strategies in the hospitality industry. With the aid of a theoretical framework this paper explores three types of behavioural characteristics: alliance attribute; communication behaviour; and alliance management to examine cost and service benefits for alliance success within one umbrella organisation in the German hospitality industry. The theoretical framework of the paper built on the model of Vanpoucke and Vereecke (2010), incorporating a top management perspective to test and extend an umbrella brand. Design/methodology: Semi-structured interviews with a sample of senior managers were undertaken in Germany at the headquarters of Ringhotels v.E. Content analysis of the data collected was implemented to increase understanding of the research phenomenon with regard to relationships and the conceptual framework applied. The results were presented in the tables with discussions about the qualitative research Findings: The results of the study showed that behavioural characteristics played a significant role in explaining overall alliance success on cost and service benefits. A good level of quality presented in Ringhotels’ services, marketing, risk and coordination were found to be a better predictor of success when absence of management and lack of trust hampered good performance. Originality/Contribution: The study offers insights into the management of relationships within Ringhotels v.E. and how these can be better managed. The main contribution of the work fills in a gap currently existing in the literature about umbrella branding within the hospitality industry

Control of unstable steady states by time-delayed feedback methods

We show that time-delayed feedback methods, which have successfully been used to control unstable periodic ortbits, provide a tool to stabilize unstable steady states. We present an analytical investigation of the feedback scheme using the Lambert function and discuss effects of both a low-pass filter included in the control loop and non-zero latency times associated with the generation and injection of the feedback signal.Comment: 8 pages, 11 figure

Improved high-temperature resistant matrix resins

A study was performed with the objective of developing matrix resins that exhibit improved thermo-oxidative stability over state-of-the-art high temperature resins for use at temperatures up to 644 K (700 F) and air pressures up to 0.7 MPa (100 psia). The work was based upon a TRW discovered family of polyimides currently licensed to and marketed by Ethyl Corporation as EYMYD(R) resins. The approach investigated to provide improved thermo-oxidative properties was to use halogenated derivatives of the diamine, 2, 2-bis (4-(4-aminophenoxy)phenyl) hexafluoropropane (4-BDAF). Polyimide neat resins and Celion(R) 12,000 composites prepared from fluorine substituted 4-BDAF demonstrated unexpectedly lower glass transition temperatures (Tg) and thermo-oxidative stabilities than the baseline 4-BDAF/PMDA polymer

Fetal Medicine Foundation fetal and neonatal population weight charts

Objective: To develop fetal and neonatal population weight charts. The rationale for this objective is that while reference ranges of estimated fetal weight (EFW) are representative of the whole population, the traditional approach of deriving birth-weight (BW) charts is misleading because a high proportion of babies born preterm arises from pathological pregnancies. We propose that the reference population for BW charts, as in the case of EFW charts, should be all babies at a given gestational age including those still in utero. Patients: Two sources of data were used for this study and in both the inclusion criteria were singleton pregnancy, dating by fetal crown-rump length at 11+0 to 13+6 weeks’ gestation, ultrasonographic measurements of fetal head circumference (HC), abdominal circumference (AC) and femur length (FL), and livebirth of phenotypically normal neonate. Dataset 1, comprised a sample of 5,163 paired measurements of EFW and BW; the ultrasound scans were carried out at 22-43 weeks’ gestation and birth occurred within 2 days of the ultrasound examination. The EFW was derived from the measurements of HC, AC and FL using the formula reported by Hadlock et al. in 1985. Dataset 2, comprised a sample of 95,579 pregnancies with EFW obtained by routine ultrasonographic fetal biometry at 20+0 to 23+6 weeks’ gestation (n=45,034), or at 31+0 to 33+6 weeks (n=19,224) or at 35+0 to 36+6 weeks (n=31,321); for the purpose of this study we included data for only one of the three visits. Methods: In the development of reference ranges of EFW and BW with gestational age the following assumptions were made: first, the EFW and BW have a common median, dependent on gestational age and second, deviations from the median occur in both EFW and BW and these deviations are correlated with different levels of spread for EFW and BW, dependent on gestational age. We adopted a Bayesian approach to inference combining information from the two datasets using Markov Chain Monte–Carlo sampling (MCMC). The fitted model assumed that the mean log transformed measurements of EFW and BW are related to gestational age according to a cubic equation and that deviations about the mean follow a bivariate Gaussian distribution. Results: In the case of EFW in dataset 2 there was a good distribution of values 90th, >95th and >97th percentiles of the reference range of EFW with gestational age throughout the gestational age range of 20+0- 36+6 weeks. In the case of BW there was a good distribution of values only for the cases born at >39 weeks’ gestation. For preterm births, particularly at 27-36 weeks, the BW was below the 3rd, 5th and 10th percentiles in a very high proportion of cases and this was particularly marked for cases of iatrogenic birth. The incidence of SGA fetuses and neonates in the respective EFW and BW charts was higher in women of Black than White racial origin. Conclusion: We established a BW chart for the population of all babies at a given gestational age, including those still in utero, which overcomes the problem of underestimation of growth restriction in preterm births. The BW and EFW charts have a common median but they differ in the levels of spread from the median

Impact of new definitions of pre-eclampsia on incidence and performance of first-trimester screening

Objective: The traditional definition of pre-eclampsia (PE) is based on the development of hypertension and proteinuria. This has been revised recently to include cases without proteinuria but with evidence of renal, hepatic or hematological dysfunction. The aim of this study was to examine the impact of new definitions of PE on, first, the incidence and severity of the disease and, second, the performance of the competing-risks model for first-trimester assessment of risk for PE. Methods: This was a retrospective study of 66 964 singleton pregnancies that were classified as having PE, gestational hypertension (GH) or no PE or GH, according to the traditional criteria of the International Society for the Study of Hypertension in Pregnancy (ISSHP-old), which defines PE as the presence of both hypertension and proteinuria. We reviewed the records of pregnancies with GH, and those cases with high creatinine or liver enzymes or low platelet count were reclassified as having PE, according to the new criteria of ISSHP (ISSHP-new) and the new criteria of the American College of Obstetricians and Gynecologists (ACOG). The groups of PE according to the traditional and new criteria were compared for, first, gestational age at delivery, birth-weight percentile and incidence of a small-for-gestational-age (SGA) neonate with birth weight < 10th percentile and perinatal death, and, second, the predictive performance for preterm PE of the competing-risks model based on the combination of maternal risk factors, uterine artery pulsatility index, mean arterial pressure and serum placental growth factor at 11-13 weeks' gestation (triple test). Results: According to ISSHP-old, 1870 (2.8%) cases had PE, 2182 (3.3%) had GH and 62 912 (94.0%) had no PE or GH. The incidence of PE according to ACOG was 3.0% (2029/66 964) and ISSHP-new was 3.4% (2301/66 964). Median gestational age at delivery in the extra cases of PE according to ACOG (difference, 1.3 weeks; 95% CI, 0.71-1.71 weeks) and in the extra cases of PE according to ISSHP-new (difference, 1.5 weeks; 95% CI, 1.29-1.71 weeks) was higher than in cases with PE according to ISSHP-old (38.4 weeks). The incidence of a SGA neonate in the extra cases of PE according to ACOG (relative risk, 0.57; 95% CI, 0.42-0.79) and in the extra cases of PE according to ISSHP-new (relative risk, 0.52; 95% CI, 0.42-0.65) was lower than in the cases of PE according to ISSHP-old (33.64%). In first-trimester screening for preterm PE by the triple test, the detection rate, at a 10% false-positive rate, was 75.9% (95% CI, 70.8-80.6%) for ISSHP-old, 74.3% (95% CI, 69.2-79.0%) for ACOG and 74.0% (95% CI, 68.9-78.6%) for ISSHP-new. Conclusions: The new definitions of PE resulted in, first, an increase in pregnancies classified as having PE but the additional cases had milder disease, and, second, a non-significant decrease in the performance of first-trimester screening for PE

Interferometric Detection of Linear Polarization from Sagittarius A* at 230 GHz

We measured the linear polarization of Sagittarius A* to be 7.2 +/- 0.6 % at 230 GHzusing the BIMA array with a resolution of 3.6 x 0.9 arcsec. This confirms the previously reported detection with the JCMT 14-m antenna. Our high resolution observations demonstrate that the polarization does not arise from dust but from a synchrotron source associated with Sgr A*. We see no change in the polarization position angle and only a small change in the polarization fraction in four observations distributed over 60 days. We find a position angle 139 +/- 4 degrees that differs substantially from what was found in earlier JCMT observations at the same frequency. Polarized dust emission cannot account for this discrepancy leaving variability and observational error as the only explanations. The BIMA observations alone place an upper limit on the magnitude of the rotation measure of 2 x 10^6 rad m^-2. These new observations when combined with the JCMT observations at 150, 375 and 400 GHz suggest RM =-4.3 +/- 0.1 x 10^5 rad m^-2. This RM may be caused by an external Faraday screen. Barring a special geometry or a high number of field reversals, this RM rules out accretion rates greater than ~ 10^-7 M_sun y^-1. This measurement is inconsistent with high accretion rates necessary in standard advection dominated accretion flow and Bondi-Hoyle models for Sgr A*. It argues for low accretion rates as a major factor in the overall faintness of Sgr A*.Comment: accepted for publication in ApJ, 18 pages, 4 figure