Value of using liver FDG uptake as background activity in standardizing FDG PET/CT studies

Thesis (M.A.)--Boston UniversityThe standardized uptake value (SUV) is increasingly being used for diagnosis, staging, and monitoring disease in clinical oncology. Comparing tumor SUV to background SUV is an attractive way to minimize variability and ensure the quality of scans across different institutions. The liver has been identified as a potential source for background normalization, however no studies have compared the liver to other background sites for a variety of cancers. The purpose of this study was to evaluate the use of liver uptake for the standardization of FDG PET/CT imaging. Scans from 145 patients were prospectively reviewed under the supervision of a radiologist with board certification in nuclear medicine (R.M.S. , 3 years of experience). Liver SUV values were correlated to mediastinum SUV values in lung and breast cancer patients, and internal jugular vein (IJV) SUV values in head and neck cancer patients. The independent t-test was used to determine if there was a statistically significant affect of the amount of incubation time or use of intravenous contrast on the SUV. For the lung and breast cancer patients, a strong correlation was observed between the mediastinum SUVmean and liver SUVmean (r = 0.89), whereas for the head and neck cancer patients, a weaker correlation was observed between the IJV SUVmean and the liver SUVmean (r = 0.69). Neither the amount of incubation time nor the use of IV contrast demonstrated a significant affect on the SUV. We conclude that liver SUVmean may be used to standardize FOG PET/CT studies in cancers of the lung, breast and head and neck. However, additional studies in other cancers as well as the affects of age, gender, benign disease and use of chemotherapy are still desired before widespread adoption of this standard

Pinning, de-pinning and re-pinning of a slowly varying rivulet

The solutions for the unidirectional flow of a thin rivulet with prescribed volume flux down an inclined planar substrate are used to describe the locally unidirectional flow of a rivulet with constant width (i.e. pinned contact lines) but slowly varying contact angle as well as the possible pinning and subsequent de-pinning of a rivulet with constant contact angle and the possible depinning and subsequent re-pinning of a rivulet with constant width as they flow in the azimuthal direction from the top to the bottom of a large horizontal cylinder. Despite being the same locally, the global behaviour of a rivulet with constant width can be very different from that of a rivulet with constant contact angle. In particular, while a rivulet with constant non-zero contact angle can always run from the top to the bottom of the cylinder, the behaviour of a rivulet with constant width depends on the value of the width. Specifically, while a narrow rivulet can run all the way from the top to the bottom of the cylinder, a wide rivulet can run from the top of the cylinder only to a critical azimuthal angle. The scenario in which the hitherto pinned contact lines of the rivulet de-pin at the critical azimuthal angle and the rivulet runs from the critical azimuthal angle to the bottom of the cylinder with zero contact angle but slowly varying width is discussed. The pinning and de-pinning of a rivulet with constant contact angle, and the corresponding situation involving the de-pinning and re-pinning of a rivulet with constant width at a non-zero contact angle which generalises the de-pinning at zero contact angle discussed earlier, are described. In the latter situation, the mass of fluid on the cylinder is found to be a monotonically increasing function of the constant width

A Clinical and Experimental Study of Intraperitoneal Antiprotease Therapy in Acute Pancreatitis

Peritoneal exudate appears to be toxic in experimental pancreatitis, possibly as a result of overwhelming of its antiprotease defences by proteolytic enzymes released from the pancreas. Removal of this exudate by peritoneal lavage has been a uniformly successful therapy. In contrast, the role of the protease-antiprotease balance in peritoneal exudate in human acute pancreatitis, and its relationship with the early "shock-like" illness which may complicate severe attacks, has not been clearly defined and the efficacy of peritoneal lavage is unproven. This thesis has addressed 3 main issues. The nature and extent of the problem presented by acute pancreatitis has been investigated, as have means for monitoring and predicting the severity of the illness. The major part of the thesis has examined aspects of the protease-antiprotease balance in the peritoneal exudate that complicates severe acute pancreatitis, and the efficacy of treatment by the administration of intraperitoneal antiproteases in experimental pancreatitis and in man. Incidence and mortality The incidence and mortality trends of acute pancreatitis in Scotland have been reviewed between 1961 and 1985 using data from the Scottish Hospital In-patient Statistics. Over this 25 year period the number of patients discharged with a diagnosis of acute pancreatitis increased 11-fold in males and 4-fold in females and may be largely explained by an increased frequency of diagnosis (diagnostic rate), due to greater clinical awareness and more frequent diagnostic testing. The absolute mortality rate has increased slightly although, because of the marked increase in incidence, the case mortality rate has fallen from 17.8% to 5.6%. The incidence and mortality trends were also examined in Glasgow Royal Infirmary between 1974 and 1984, over which period the diagnostic rate was thought to have been unchanged. Despite a 23% fall in the catchment population the annual number of admissions remained relatively constant, suggesting a true increase in local incidence. Amongst the fatal attacks, 42% had the diagnosis first made at post mortem, the fall in overall mortality from 14.9% to 10.8% reflecting a reduction in the numbers first diagnosed at post mortem. Mortality amongst patients diagnosed in life was unchanged at 9% throughout, thus when the effect of an increased diagnostic rate is excluded, improvements in therapy do not appear to have influenced the mortality rate. Prediction of outcome Investigation of invasive or expensive therapies requires that patients with severe pancreatitis and at risk of a complicated attack, are identified accurately, early in their illness. There is also a need to develop means to objectively monitor the course of the illness and any response to therapy, which might aid their management. Simple clinical assessment was shown to have the highest overall accuracy in predicting outcome but, even 48 hours post-admission, detected under 50% of those developing complications. Multiple factor scoring systems provided a useful prediction of outcome, particularly for attacks associated with alcohol abuse, but provided a "once only" prediction and failed to allow for sequential monitoring of the course of an attack. Sequential monitoring of 5 different complement factors was of no value in discriminating complicated from uncomplicated attacks. Serum antiproteases demonstrated a falling alpha2macroglobulin concentration and a rising alpha1antiprotease concentration in complicated attacks, both providing useful discrimination. C-reactive protein provided better discrimination but peak levels (>210mg/1 on the 2nd, 3rd or 4th day), while providing equivalent accuracy to the multiple factor scoring systems incurred a similar delay. C-reactive protein concentrations fell with clinical improvement, persistently high levels (>120mg/1 on day 7) indicating an increased risk of complication. The APACHE II scoring system provided a prediction of outcome within a few hours of admission. The peak score recorded in the first 3 days provided greater accuracy, equivalent to the multiple factor scoring systems, but incurred a similar delay. The APACHE II was objective, reproducible and appeared to reflect improvement or deterioration in the patient's clinical condition and may permit sequential monitoring of the course of the illness. None of the scoring systems or factors examined was able to predict complicated attacks earlier and more accurately than multiple factor scoring systems. C-reactive protein and APACHE II both appear to be of value, C-reactive protein for its simplicity and both for objective monitoring during the course of an attack. Intraperitoneal antiprotease therapy Retrograde intraductal injection of sodium taurocholate produced a severe pancreatitis in rats, death usually occurring within 24 hours. Only a small proportion of patients die of such a fulminant, rapidly fatal illness but it is this early "shock-like" illness which therapy aims to ameliorate and, therefore, this model appeared an appropriate one to study. (Abstract shortened by ProQuest.)

Partial ownership arrangements in the Japanese automobile industry; 1990-2000

The end of the 1990’s saw a number of foreign automobile manufacturers become the largest shareholders in several Japanese automobile manufacturers. It seems logical to conclude that a firm only enters into a partial ownership arrangement (POA) if it is profit maximizing. However, research to date has treated POAs as if exogenous to the model. This paper develops a model that assumes POAs are determined endogenously. Data for the Japanese automobile industry are then used to investigate the factors that determine whether a firm enters into a POA, and the effects a POA has on the price-cost margin. The findings of this paper suggest that while both foreign and domestic firms take an interest in product mix when exploring POAs in the Japanese market, they have differing profit incentives. Furthermore, the level of ownership has a positive effect on POAs.partial ownership arrangements, price-cost margin, technology transfers

Marketing Pastimes: Comparing the Brand Strengths of Real Madrid & The New York Yankees

In March of 2012, Forbes Magazine ranked the most valuable brands in all of sports. Trailing only Manchester United’s $2.235 billion valuation, the next most valuable franchises are Spain’s Real Madrid of La Liga BBVA, and Major League Baseball’s New York Yankees. As the two of the three most dominant brands in all of sports, Real Madrid and the New York Yankees are frequently mentioned in the same context as one another, but rarely discussed through more extensive market research comparing their brand management strategies. By utilizing Kevin Keller’s acclaimed Customer-Based Brand Equity model, the relative strength of the brands for Real Madrid and the New York Yankees will be assessed based on their ability to successfully integrate six core components within their brand: brand salience, brand performance, brand imagery, brand judgments, brand feelings, and brand resonance. Through a combination of these indicators of brand strength, this paper will investigate which brand is stronger at the domestic and international levels, as both a sports team and commercial enterprise. Awarded by FIFA in 2008 as the “Best Club of the 20th Century,” Real Madrid’s remarkable history is unparalleled by any other team in the world’s most popular sport: soccer. With a record 31 LIGA BBVA and 9 UEFA Champions League titles, Real Madrid’s sporting excellence is matched only by its brand equity, with a valuation of$1.877 billion. Owned by a coalition of members, known as “Madridistas,” Real Madrid has capitalized on its brand loyalty, translating recent team performances into $214 million in operating income, thereby establishing the club as the most profitable brand in all of team sports in 2011. Valued slightly below Real Madrid at$1.85 billion, the New York Yankees are the most storied franchise in all of American sports. As the most acclaimed brand in America’s favorite pastime, the New York Yankees have won an incredible 27 World Series Champions - 16 more than the 2nd place St. Louis Cardinals and 3 more than any other North American sports franchise, in the NHL’s Montreal Canadiens. As a true sports enterprise, the New York Yankees generate the most revenue of all sports teams worldwide and represent a core component of Yankee Global Enterprises LLC (YGE), with a collective valuation of $5.1 billion. Though typically discussed in conjunction with the other, Real Madrid and the New York Yankees have each reached their respective valuations and positioning as global brands in very distinct ways. With its commercial business model roughly only a decade old, Real Madrid’s brand resonance, and subsequent brand equity, is derivative of the universal nature of soccer, taking advantage of the captivation of audiences worldwide and its presence as a truly global brand. The New York Yankees, have embraced this model since 1973 under the direction of George Steinbrenner, and have amassed such brand strength through its attentiveness in its domestic market and the salience of YGE. With virtually equal brand valuations, Real Madrid has maintained a more effective positioning as a global sports brand, with the New York Yankees utilizing its domestic strength to influence global markets. Ultimately, due to their longer season and greater local population, the Yankees are a stronger domestic brand, with Real Madrid’s global appeal catering to soccer fans enabling them to become the stronger global brand

X-rays from Compton scattering around accreting black holes

Compton scattering is one of the most important radiation processes from accreting compact objects. Hard X-rays can be produced by Compton upscattering of soft seed photons from the accretion disk. Here we use both theoretical and observational methods to investigate the hard X-ray emission around accreting Black Holes. We attempt to observationally constrain the geometry of the accretion flow using the observed spectra from the outburst of a transient black hole. The rapid rise of the hard X-ray flux is almost certainly associated with most of the disk mass moving inwards, so the optically thick disk should not extend down to the last stable orbit until the outburst peak. The low/hard state is seen at the start of the rise showing that this is probably associated with a truncated disk. Attempts to derive the inner disk radius from reflection model parameters are inconclusive due to the effects of ionization. We describe a new approach to numerically modelling Compton scattering around accreting sources by solving the distribution functions. This approach (based on work by Guilbert 1981) involves breaking the scattering into individual segments of space and time. We show how a coarse angle grid can be adapted to mimic an arbitrarily fine grid with very little increase in run-time. The resulting code automatically includes time dependent behaviour. We extend the code to calculate the time dependent, self consistent electron distribution resulting from the Compton cooling. This can be used even where the Compton cooling time is shorter than the light crossing time. We show that any system in which the seed photons are dominated by reprocessing should produce soft lags of the order of the light crossing time. Future observations, with more sophisticated satellites, may be able to identify this lag

Importer Loyalty in International Wheat Markets

International Relations/Trade,