AN ANALYSIS OF THE PROFILES AND MOTIVATIONS OF HABITUAL COMMODITY SPECULATORS

The focus of this study is the habitual speculator in commodity futures markets. The speculator's activity broadens a market, creates essential liquidity, and performs an irreplaceable pricing function. Working knowledge of the profiles and motivations of habitual speculators is essential to both market theorist and policy makers. Responses to a 73 question survey were collected directly from retail commodity brokers with offices in Alabama. Each questionnaire recorded information on an individual commodity client who had traded for an extended period of time. The typical trader studied is a married, white male, age 52. He is affluent and well educated. He is a self-employed business owner who can recover from financial setbacks. He is a politically right wing conservative involved in the political process. He assumes a good deal of risk in most phases of his life. He is both an aggressive investor and an active gambler. This trader does not consider preservation of his commodity capital to be a very high trading priority. As a result, he rarely uses stop loss orders. He wins more frequently than he loses (over 51% of the time) but is an overall net loser in dollar terms. In spite of recurring trading losses, he has never made any substantial change in his basic trading style. To this trader, whether he won or lost on a particular trade is more important than the size of the win or loss. Thus he consistently cuts his profits short while letting his losses run. He also worries more about missing a move in the market by being on the sidelines than about losing by being on the wrong side of a market move; i.e., being in the action is more important than the financial consequences. Participating brokers confirmed that for the majority of the speculators studied, the primary motivation for continuous trading is the recreational utility derived largely from having a market position.Marketing,

An Experimental Study of Effects of Overlaying Tissues on HIFU Lesion

Understanding the effect of overlaying tissues on HIFU lesion is crucial for estimating HIFU dose distribution at a target tissue. We have run a series of experiments to systematically observe the effects of the overlaying tissues on the HIFU beam and ultimately the lesion created in the target tissue. First, we mapped out the HIFU transducer beam (in low power) under water without and with different overlaying tissue layers. Then, we performed a series of experiments in high power to create lesions in target tissues (e.g., liver) without and with overlaying tissues (e.g. muscle). The lesions are characterized by slicing the tissues and reconstructing the 3D lesion from calibrated pictures of the target tissue slices. The low power beam measurements show significant effects in terms of severe beam wave‐field amplitude distortion due to phase aberration introduced by velocity inhomogeneity in the overlaying tissues. These results compare well qualitatively with the computational models. The results from the high power HIFU lesions in a similar setup using various tissues, including liver and muscle, provide understanding of the significance of phase aberration in overlaying tissues and could prove useful towards high precision HIFU therapy

Radiologic and Histologic Findings of Locally Advanced Mucoepidermoid Carcinoma Managed with Total Surgical Excision

The present case report provides images from computed tomography and histology of a patient with a salivary gland neoplasm consistent with mucoepidermoid carcinoma

Estimating the Effects of Part Size on Direct Laser Deposition Parameter Selection via a Thermal Resistance Network Approach

A mathematical model for heat transfer during the Directed Energy Deposition (DED) process is proposed. The model employs the thermal resistance network analogy and is developed to aid one in predicting part size effects on its temperature distribution during manufacture, and in how to compensate such effects via suitable process parameter selection. The model predicts a pseudo steady-state temperature response in the melt pool. The temperature variation along the heat affected zone of a thin-walled part is estimated while assuming deposition is occurring far from the substrate. Predicted melt pool and bulk part temperatures are validated against Laser Engineering Net Shaping (LENSTM) experimental data obtained via a dual-wavelength pyrometer and in-chamber infrared camera, respectively. Results demonstrate that the model may be used to predict an average melt pool temperature. Bulk, calculated temperature distribution needs to be further investigated to find a more suitable heat transfer coefficient surrounding the part.Mechanical Engineerin

Timing Noise in SGR 1806-20

We have phase connected a sequence of RXTE PCA observations of SGR 1806-20 covering 178 days. We find a simple secular spin-down model does not adequately fit the data. The period derivative varies gradually during the observations between 8.1 and 11.7 * 10^-11 s/s (at its highest, ~40% larger than the long term trend), while the average burst rate as seen with BATSE drops throughout the time interval. The phase residuals give no compelling evidence for periodicity, but more closely resemble timing noise as seen in radio pulsars. The magnitude of the timing noise, however, is large relative to the noise level typically found in radio pulsars. Combining these results with the noise levels measured for some AXPs, we find all magnetar candidates have \Delta_8 values larger than those expected from a simple extrapolation of the correlation found in radio pulsars. We find that the timing noise in SGR 1806-20 is greater than or equal to the levels found in some accreting systems (e.g., Vela X-1, 4U 1538-52 and 4U 1626-67), but the spin-down of SGR 1806-20 has thus far maintained coherence over 6 years. Alternatively, an orbital model with a period P_orb = 733 days provides a statistically acceptable fit to the data. If the phase residuals are created by Doppler shifts from a gravitationally bound companion, then the allowed parameter space for the mass function (small) and orbital separation (large) rule out the possibility of accretion from the companion sufficient to power the persistent emission from the SGR.Comment: 11 pages, accepted for publication in ApJ Letter

The Dilemma of Using Sward Height as a Management Tool for Intensively Grazed Sheep Pasture in Spring

Sward height is often used as a tool for both animal and pasture management, especially when continuously grazing pasture. For example, sward height has been used to define the conditions for optimal feed intake of multiple-bearing ewes, both before and after lambing (Everett-Hincks et al.2005; Morris and Kenyon 2004). Sward height is easily applied by the grazier and so becomes an effective tool. However, changes in the leaf distribution and relative species makeup of the sward both seasonally (Thomson et al. 2001) and in response to grazing management (Webby and Pengelly 1986) mean that the amount of pasture per unit height will change. When these changes occur a dilemma is presented to the grazier. How do they manage the trade-off between a simple indicator for management decisions and the lost opportunity of harvesting pasture mass that may be accumulating below the assigned sward height? This paper presents data from an experiment that investigated the impacts of defoliation strategies on sward of differing starting masses, with defoliation management based on height rather than mass. The paper quantifies the accumulation of herbage below defoliation height and highlights the dilemma of using sward height as a management tool when aiming to maximise the utilisation of our pasture resource

Background reionization history from omniscopes

The measurements of the 21-cm brightness temperature fluctuations from the neutral hydrogen at the Epoch of Reionization (EoR) should inaugurate the next generation of cosmological observables. In this respect, many works have concentrated on the disambiguation of the cosmological signals from the dominant reionization foregrounds. However, even after perfect foregrounds removal, our ignorance on the background reionization history can significantly affect the cosmological parameter estimation. In particular, the interdependence between the hydrogen ionized fraction, the baryon density and the optical depth to the redshift of observation induce nontrivial degeneracies between the cosmological parameters that have not been considered so far. Using a simple, but consistent reionization model, we revisit their expected constraints for a futuristic giant 21-cm omniscope by using for the first time Markov Chain Monte Carlo (MCMC) methods on multiredshift full sky simulated data. Our results agree well with the usual Fisher matrix analysis on the three-dimensional flat sky power spectrum but only when the above-mentioned degeneracies are kept under control. In the opposite situation, Fisher results can be inaccurate. We show that these conditions can be fulfilled by combining cosmic microwave background measurements with multiple observation redshifts probing the beginning of EoR. This allows a precise reconstruction of the total optical depth, reionization duration and maximal spin temperature. Finally, we discuss the robustness of these results in presence of unresolved ionizing sources. Although most of the standard cosmological parameters remain weakly affected, we find a significant degradation of the background reionization parameter estimation in presence of nuisance ionizing sources.Comment: 22 pages, 18 figures, uses RevTex. References added, matches published versio

Inflammation in benign prostate tissue and prostate cancer in the finasteride arm of the Prostate Cancer Prevention Trial

BACKGROUND: A previous analysis of the placebo arm of the Prostate Cancer Prevention Trial (PCPT) reported 82% overall prevalence of intraprostatic inflammation and identified a link between inflammation and higher-grade prostate cancer and serum PSA. Here we studied these associations in the PCPT finasteride arm. METHODS: Prostate cancer cases (N=197) detected either on a clinically indicated biopsy or on protocol-directed end-of-study biopsy, and frequency-matched controls (N=248) with no cancer on an end-of-study biopsy were sampled from the finasteride arm. Inflammation in benign prostate tissue was visually assessed using digital images of H&E stained sections. Logistic regression was used for statistical analysis. RESULTS: In the finasteride arm, 91.6% of prostate cancer cases and 92.4% of controls had at least one biopsy core with inflammation in benign areas; p < 0.001 for difference compared to placebo arm. Overall, the odds of prostate cancer did not differ by prevalence (OR=0.90, 95% CI 0.44-1.84) or extent (P-trend=0.68) of inflammation. Inflammation was not associated with higher-grade disease (prevalence: OR=1.07, 95% CI 0.43-2.69). Furthermore, mean PSA concentration did not differ by the prevalence or extent of inflammationin either cases or controls. CONCLUSION: The prevalence of intraprostatic inflammation was higher in the finasteride than placebo arm of the PCPT, with no association with higher-grade prostate cancer. IMPACT: Finasteride may attenuate the association between inflammation and higher-grade prostate cancer. Moreover, the missing link between intraprostatic inflammation and PSA suggests that finasteride may reduce inflammation-associated PSA elevation