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Long-term Information (long-term + information)
Selected AbstractsRISK FACTORS FOR RECURRENT BILE DUCT STONES AFTER ENDOSCOPIC PAPILLARY BALLOON DILATION: LONG-TERM FOLLOW-UP STUDYDIGESTIVE ENDOSCOPY, Issue 2 2009Akira Ohashi Background:, Little is known about the long-term results of endoscopic papillary balloon dilation (EPBD) for bile duct stones. Methods:, Between 1995 and 2000, 204 patients with bile duct stones successfully underwent EPBD and stone removal. Complete stone clearance was confirmed using balloon cholangiography and intraductal ultrasonography (IDUS). Long-term outcomes of EPBD were investigated retrospectively in the year 2007, and risk factors for stone recurrence were multivariately analyzed. Results:, Long-term information was available in 182 cases (89.2%), with a mean overall follow-up duration of 9.3 years. Late biliary complications occurred in 22 patients (12.1%), stone recurrence in 13 (7.1%), cholangitis in 10 (5.5%), cholecystitis in four, and gallstone pancreatitis in one. In 11 of 13 patients (84.6%), stone recurrence developed within 3 years after EPBD. All recurrent stones were bilirubinate. Multivariate analysis identified three risk factors for stone recurrence: dilated bile duct (>15 mm), previous cholecystectomy, and no confirmation of clean duct using IDUS. Conclusion:, Approximately 7% of patients develop stone recurrence after EPBD; however, retreatment with endoscopic retrograde cholangiopancreatography is effective. Careful follow up is necessary in patients with dilated bile duct or previous cholecystectomy. IDUS is useful for reducing stone recurrence after EPBD. [source] Long-term information, short-lived securitiesTHE JOURNAL OF FUTURES MARKETS, Issue 5 2006Dan Bernhardt The authors explore strategic trade in short-lived securities by agents who have private information that is potentially long-term, but do not know how long their information will remain private. Trading short-lived securities is profitable only if enough of the private information becomes public prior to contract expiration; otherwise the security will worthlessly expire. How this results in trading behavior fundamentally different from that observed in standard models of informed trading in equity is highlighted. Specifically, it is shown that informed speculators are more reluctant to trade shorter-term securities too far in advance of when their information will necessarily be made public, and that existing positions in a shorter-term security make future purchases more attractive. Because informed speculators prefer longer-term securities, this can make trading shorter-term contracts more attractive for liquidity traders. The conditions are characterized under which liquidity traders choose to incur extra costs to roll over short-term positions rather than trade in distant contracts, providing an explanation for why most longer-term derivative security markets have little liquidity and large bid-ask spreads. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:465,502, 2006 [source] Web Discovery and Filtering Based on Textual Relevance Feedback LearningCOMPUTATIONAL INTELLIGENCE, Issue 2 2003Wai Lam We develop a new approach for Web information discovery and filtering. Our system, called WID, allows the user to specify long-term information needs by means of various topic profile specifications. An entire example page or an index page can be accepted as input for the discovery. It makes use of a simulated annealing algorithm to automatically explore new Web pages. Simulated annealing algorithms possess some favorable properties to fulfill the discovery objectives. Information retrieval techniques are adopted to evaluate the content-based relevance of each page being explored. The hyperlink information, in addition to the textual context, is considered in the relevance score evaluation of a Web page. WID allows users to provide three forms of the relevance feedback model, namely, the positive page feedback, the negative page feedback, and the positive keyword feedback. The system is domain independent and does not rely on any prior knowledge or information about the Web content. Extensive experiments have been conducted to demonstrate the effectiveness of the discovery performance achieved by WID. [source] Diet reconstruction and historic population dynamics in a threatened seabirdJOURNAL OF APPLIED ECOLOGY, Issue 4 2007D. RYAN NORRIS Summary 1For the overwhelming majority of species, we lack long-term information on the dynamics of populations. As a consequence, we face considerable uncertainty about how to discriminate among competing hypotheses of population decline and design conservation plans. 2The marbled murrelet Brachyramphus marmoratus is a small seabird that nests in coastal old-growth forest but feeds year-round in near-shore waters of the north-eastern Pacific. Although a decline in nesting habitat is the primary reason why marbled murrelets are listed as threatened in Canada, nest predation and food availability may also influence population abundance. To examine the hypothesis that murrelet populations are influenced by variation in diet quality, we analysed stable-carbon and -nitrogen isotopes in feathers of museum specimens collected in the Georgia Basin, British Columbia. 3Between 1889 and 1996, we found a decline in stable isotopic signatures that was approximately equal to a 62% drop in trophic feeding level. We also found that the estimated proportion of fish in murrelet diet was related closely to murrelet abundance over the past 40 years, as estimated from volunteer surveys. Using these isotopic data, we modelled population size as a function of variation in reproductive rate due to changes in diet quality and found that our model matched closely the 40-year field estimates. We then applied our 107-year isotopic record to the model to back-cast estimates of population growth rate to 1889. 4Our results suggest that, up to the 1950s, murrelet populations in the Georgia Basin were capable of growing and were probably limited by factors other than diet quality. After this period, however, our results imply that murrelets were often, but not solely, limited by diet quality. 5Synthesis and applications. Protecting nesting habitat may not be sufficient to rebuild populations of this highly secretive and threatened seabird and recovery might also require the restoration of marine habitat quality, as well as a better understanding of how ocean climate affects prey abundance and reproductive rate. Combined with contemporary demographic data, stable isotope analysis of historic samples provides a unique opportunity to reconstruct population histories for species where we lack long-term information. [source] Aqueous chloramine diffusion into elastomersJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010Raja M. Nagisetty Abstract Aqueous chloramine diffusion into styrene butadiene rubber (SBR) and natural rubber was analyzed using approximate analytical and numerical solutions of Fick's second law of diffusion to develop long-term mass intake prediction curves. Diffusion coefficients were calculated for 1 mg/L chloramine concentration at three temperatures (23, 45, and 70°C) and also for 23°C at three chloramine concentrations (1, 30, and 60 mg/L). The reasonableness of using increased temperature and/or chloramine concentration to accelerate the diffusion process to obtain long-term information was discussed. For 1 mg/L chloramine concentration, the activation energy for the diffusion of chloramines into SBR and natural rubber were computed to be 51.13 and 77.29 kJ/mol, respectively. Also, concentration profiles were developed to understand the extent of penetration through the elastomer thickness over time and temperature. Considering the reports of elastomeric compound failure in chloramine disinfectant water distribution systems because of swelling, this study will be helpful in understanding the performance of the elastomeric compounds in the system. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Moult speed affects structural feather ornaments in the blue titJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2009M. GRIGGIO Abstract Growing evidence suggests that structural feather colours honestly reflect individual quality or body condition but, contrary to pigment-based colours, it is not clear what mechanism links condition to reflectance in structural feather colours. We experimentally accelerated the moult speed of a group of blue tits (Cyanistes caeruleus) by exposing them to a rapidly decreasing photoperiod and compared the spectral characteristics of their structural feather colours with those of control birds. Blue tits were sexually dimorphic on the UV/blue crown and on the white cheek feathers. Moult speed, however, dramatically reduced brightness and the saturation only on the UV/blue crown feathers, whereas structural white on the cheek feathers was basically unaffected by moult speed. Given that the time available for moulting is usually confined to the period between the end of the breeding season and migration or wintering, UV/blue colours, but not structural white, may convey long-term information about an individual's performance during the previous breeding season. The trade-off between fast moulting and structural colour expression may represent a previously unrecognized selective advantage for early-breeding birds. [source] High-protein Weight-loss Diets: Are They Safe and Do They Work?NUTRITION REVIEWS, Issue 7 2002A Review of the Experimental, Epidemiologic Data Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. [source] | |||||||||||||