Hedonic Price Analysis of Thoroughbred Broodmares in Foal

Thoroughbred broodmares are the foundation of a successful racing operation. This study estimated the impact of breeding, racing, genetic, and market characteristics on broodmare auction prices. Data represent 298 broodmares in foal that were sold in Keeneland's 2005 sale. Prices were most responsive to the sire's stud fee and the broodmare's age, with pronounced day-of-sale effects. Overall valuation structure appeared similar to Neibergs' results using 1996 data. Out-of-sample forecasts were far superior to naive forecasts, but were not accurate enough to use in isolation from other decision aids such as visual inspection of the horse.broodmare, Thoroughbred horses, hedonic price analysis, forecasting, Demand and Price Analysis,

Hedonic Price Analysis of Thoroughbred Broodmares in Foal

Thoroughbred broodmares are the foundation of a successful racing operation. This study estimated the impact of breeding, racing, and market characteristics on broodmare auction prices. Data represent 604 in-foal broodmares sold in Keeneland’s 2005 sale. Prices were highly responsive to the sire’s stud fee, the broodmare’s age, and progeny performance in graded stakes races, with pronounced day-of-sale effects. The stud fee marginal value was substantially lower than one break-even estimate, suggesting possible disincentives for investment in stallion services. Out-of-sample forecasts were far superior to naïve forecasts but were not accurate enough to use in isolation from other decision aids.broodmare, forecasting, hedonic price analysis, Thoroughbred, Agribusiness, Livestock Production/Industries,

Validity of the linear coupling approximation in heavy-ion fusion reactions at sub barrier energies

The role of higher order coupling of surface vibrations to the relative motion in heavy-ion fusion reactions at near-barrier energies is investigated. The coupled channels equations are solved to all orders, and also in the linear and the quadratic coupling approximations. Taking $^{64}$Ni + $^{92,96}$Zr reactions as examples, it is shown that all order couplings lead to considerably improved agreement with the experimentally measured fusion cross sections and average angular momenta of the compound nucleus for such heavy nearly symmetric systems. The importance of higher order coupling is also examined for asymmetric systems like $^{16}$O + $^{112}$Cd, $^{144}$Sm, for which previous calculations of the fusion cross section seemed to indicate that the linear coupling approximation was adequate. It is shown that the shape of the barrier distributions and the energy dependence of the average angular momentum can change significantly when the higher order couplings are included, even for systems where measured fusion cross sections may seem to be well reproduced by the linear coupling approximation.Comment: Latex file, 15 pages, 6 figure

A study of event traffic during the shared manipulation of objects within a collaborative virtual environment

Event management must balance consistency and responsiveness above the requirements of shared object interaction within a Collaborative Virtual Environment (CVE) system. An understanding of the event traffic during collaborative tasks helps in the design of all aspects of a CVE system. The application, user activity, the display interface, and the network resources, all play a part in determining the characteristics of event management. Linked cubic displays lend themselves well to supporting natural social human communication between remote users. To allow users to communicate naturally and subconsciously, continuous and detailed tracking is necessary. This, however, is hard to balance with the real-time consistency constraints of general shared object interaction. This paper aims to explain these issues through a detailed examination of event traffic produced by a typical CVE, using both immersive and desktop displays, while supporting a variety of collaborative activities. We analyze event traffic during a highly collaborative task requiring various forms of shared object manipulation, including the concurrent manipulation of a shared object. Event sources are categorized and the influence of the form of object sharing as well as the display device interface are detailed. With the presented findings the paper wishes to aid the design of future systems

Decomposition of coarse woody debris in a long-term litter manipulation experiment: A focus on nutrient availability

The majority of above-ground carbon in tropical forests is stored in wood, which is returned to the atmosphere during decomposition of coarse woody debris. However, the factors controlling wood decomposition have not been experimentally manipulated over time scales comparable to the length of this process.We hypothesized that wood decomposition is limited by nutrient availability and tested this hypothesis in a long-term litter addition and removal experiment in a lowland tropical forest in Panama. Specifically, we quantified decomposition using a 15-year chronosequence of decaying boles, and measured respiration rates and nutrient limitation of wood decomposer communities.The long-term probability that a dead tree completely decomposed was decreased in plots where litter was removed, but did not differ between litter addition and control treatments. Similarly, respiration rates of wood decomposer communities were greater in control treatments relative to litter removal plots; litter addition treatments did not differ from either of the other treatments. Respiration rates increased in response to nutrient addition (nitrogen, phosphorus, and potassium) in the litter removal and addition treatments, but not in the controls.Established decreases in concentrations of soil nutrients in litter removal plots and increased respiration rates in response to nutrient addition suggest that reduced rates of wood decomposition after litter removal were caused by decreased nutrient availability. The effects of litter manipulations differed directionally from a previous short-term decomposition study in the same plots, and reduced rates of bole decomposition in litter removal plots did not emerge until after more than 6 years of decomposition. These differences suggest that litter-mediated effects on nutrient dynamics have complex interactions with decomposition over time

Genetic diversity at the FMR1 locus in the Indonesian population

We report an analysis of allelic diversity at short tandem repeat polymorphisms within the fragile XA locus in 1069 male volunteers from twelve Indonesian sub-populations. An odd numbered allele of DXS548 was found at high frequency in all Indonesian populations. Greater allelic diversity was identified at the loci under study than has been previously reported for an Asian population. These differences distinguish the Indonesian population from all previously reported Asian, European and African populations. A high frequency of small premutation alleles, 4/120 (3.3%, 95% CI 0.9–8.3%), was identified in the Moluccan population of Hiri Island

Importance of Non-Linear Couplings in Fusion Barrier Distributions and Mean Angular Momenta

The effects of higher order coupling of surface vibrations to the relative motion on heavy-ion fusion reactions at near-barrier energies are investigated. The coupled channels equations are solved to all orders, and also in the linear and the quadratic coupling approximations. It is shown that the shape of fusion barrier distributions and the energy dependence of the average angular momentum of the compound nucleus can significantly change when the higher order couplings are included. The role of octupole vibrational excitation of ^{16}O in the ^{16}O + ^{144}Sm fusion reaction is also discussed using the all order coupled-channels equations.Comment: 8 pages, 6 figures, To be published in the Proceedings of the FUSION 97 Conference, South Durras, Australia, March 1997 (J. Phys. G

On the coexistence of stellar-mass and intermediate-mass black holes in globular clusters

In this paper, we address the question: What is the probability of stellar-mass black hole (BH) binaries co-existing in a globular cluster with an intermediate-mass black hole (IMBH)? Our results suggest that the detection of one or more BH binaries can strongly constrain the presence of an IMBH in most Galactic globular clusters. More specifically, the detection of one or more BH binaries could strongly indicate against the presence of an IMBH more massive than $\gtrsim 10^3$ M$_{\rm \odot}$ in roughly 80\% of the clusters in our sample. To illustrate this, we use a combination of N-body simulations and analytic methods to weigh the rate of formation of BH binaries against their ejection and/or disruption rate via strong gravitational interactions with the central (most) massive BH. The eventual fate of a sub-population of stellar-mass BHs (with or without binary companions) is for all BHs to be ejected from the cluster by the central IMBH, leaving only the most massive stellar-mass BH behind to form a close binary with the IMBH. During each phase of evolution, we discuss the rate of inspiral of the central BH-BH pair as a function of both the properties of the binary and its host cluster.Comment: 16 pages, 8 figures, 1 table, accepted for publication in MNRA

Incisions and reconstruction approaches for large sarcomas

Large intraabdominal, retroperitoneal, and abdominal wall sarcomas provide unique challenges in treatment due to their variable histology, potential considerable size at the time of diagnosis, and the ability to invade into critical structures. Historically, some of these tumors were considered inoperable if surgical access was limited or the consequential defect was unable to be closed primarily as reconstructive options were limited. Over time, there has been a greater understanding of the abdominal wall anatomy and mechanics, which has resulted in the development of new techniques to allow for sound oncologic resections and viable, durable options for abdominal wall reconstruction. Currently, intra-operative positioning and employment of a variety of abdominal and posterior trunk incisions have made more intraabdominal and retroperitoneal tumors accessible. Primary involvement or direct invasion of tumor into the abdominal wall is no longer prohibitive as utilization of advanced hernia repair techniques along with the application of vascularized tissue transfer have been shown to have the ability to repair large area defects involving multiple quadrants of the abdominal wall. Both local and distant free tissue transfer may be incorporated, depending on the size and location of the area needing reconstruction and what residual structures are remaining surrounding the resection bed. There is an emphasis on selecting the techniques that will be associated with the least amount of morbidity yet will restore and provide the appropriate structure and function necessary for the trunk. This review article summarizes both initial surgical incisional planning for the oncologic resection and a variety of repair options for the abdominal wall spanning the reconstructive ladder