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Selected AbstractsA Probabilistic Framework for Bayesian Adaptive Forecasting of Project ProgressCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2007Paolo Gardoni An adaptive Bayesian updating method is used to assess the unknown model parameters based on recorded data and pertinent prior information. Recorded data can include equality, upper bound, and lower bound data. The proposed approach properly accounts for all the prevailing uncertainties, including model errors arising from an inaccurate model form or missing variables, measurement errors, statistical uncertainty, and volitional uncertainty. As an illustration of the proposed approach, the project progress and final time-to-completion of an example project are forecasted. For this illustration construction of civilian nuclear power plants in the United States is considered. This application considers two cases (1) no information is available prior to observing the actual progress data of a specified plant and (2) the construction progress of eight other nuclear power plants is available. The example shows that an informative prior is important to make accurate predictions when only a few records are available. This is also the time when forecasts are most valuable to the project manager. Having or not having prior information does not have any practical effect on the forecast when progress on a significant portion of the project has been recorded. [source] Concepts for computer center power managementCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2010A. DiRienzo Abstract Electrical power usage contributes significantly to the operational costs of large computer systems. At the Hypersonic Missile Technology Research and Operations Center (HMT-ROC) our system usage patterns provide a significant opportunity to reduce operating costs since there are a small number of dedicated users. The relatively predictable nature of our usage patterns allows for the scheduling of computational resource availability. We take advantage of this predictability to shut down systems during periods of low usage to reduce power consumption. With interconnected computer cluster systems, reducing the number of online nodes is more than a simple matter of throwing the power switch on a portion of the cluster. The paper discusses these issues and an approach for power reduction strategies for a computational system with a heterogeneous system mix that includes a large (1560-node) Apple Xserve PowerPC supercluster. In practice, the average load on computer systems may be much less than the peak load although the infrastructure supporting the operation of large computer systems in a computer or data center must still be designed with the peak loads in mind. Given that a significant portion of the time, systems loads can be less than full peak, an opportunity exists for cost savings if idle systems can be dynamically throttled back, slept, or shut off entirely. The paper describes two separate strategies that meet the requirements for both power conservation and system availability at HMT-ROC. The first approach, for legacy systems, is not much more than a brute force approach to power management which we call Time-Driven System Management (TDSM). The second approach, which we call Dynamic-Loading System Management (DLSM), is applicable to more current systems with ,Wake-on-LAN' capability and takes a more granular approach to the management of system resources. The paper details the rule sets that we have developed and implemented in the two approaches to system power management and discusses some results with these approaches. Copyright © 2009 John Wiley & Sons, Ltd. [source] Efficient communication using message prediction for clusters of multiprocessorsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2002Ahmad Afsahi Abstract With the increasing uniprocessor and symmetric multiprocessor computational power available today, interprocessor communication has become an important factor that limits the performance of clusters of workstations/multiprocessors. Many factors including communication hardware overhead, communication software overhead, and the user environment overhead (multithreading, multiuser) affect the performance of the communication subsystems in such systems. A significant portion of the software communication overhead belongs to a number of message copying operations. Ideally, it is desirable to have a true zero-copy protocol where the message is moved directly from the send buffer in its user space to the receive buffer in the destination without any intermediate buffering. However, due to the fact that message-passing applications at the send side do not know the final receive buffer addresses, early arrival messages have to be buffered at a temporary area. In this paper, we show that there is a message reception communication locality in message-passing applications. We have utilized this communication locality and devised different message predictors at the receiver sides of communications. In essence, these message predictors can be efficiently used to drain the network and cache the incoming messages even if the corresponding receive calls have not yet been posted. The performance of these predictors, in terms of hit ratio, on some parallel applications are quite promising and suggest that prediction has the potential to eliminate most of the remaining message copies. We also show that the proposed predictors do not have sensitivity to the starting message reception call, and that they perform better than (or at least equal to) our previously proposed predictors. Copyright © 2002 John Wiley & Sons, Ltd. [source] Making the Leap from Researcher to Planner: Lessons from Avian Conservation Planning in the Dominican RepublicCONSERVATION BIOLOGY, Issue 1 2000Steven C. Latta Published accounts of national, multidisciplinary planning efforts and priority setting for avian conservation are not common. I describe the process and results of a broad-based, grassroots-oriented avian conservation planning workshop held in the Dominican Republic in which we designed a coordinated strategy for avian conservation in the country. The planning process sought to (1) increase communication and cooperation among conservationists; (2) familiarize participants with resources pertinent to avian conservation; (3) encourage the transfer of information between researchers and managers; (4) promote the concepts of long-term avian monitoring, avian conservation plans, and species management plans; and (5) develop a common, multidisciplinary strategy to promote the conservation of birds in the Dominican Republic. The workshop highlighted group discussions among research biologists, managers, educators, and public policy specialists to assess avian conservation needs and priorities with respect to each discipline and has since galvanized a significant portion of the conservation community around several cooperative projects involving diverse segments of the community. Avian biologists can play a significant role in conservation efforts through a willingness to work with key players in diverse fields and to envision holistic, multidisciplinary approaches to conservation issues. Resumen: Cuando los biologícos investigadores incursionan en la biología de la conservación enfrentan nuevos desafíos, especialmente en países extranjeros, al intentar prestar apoyo para esfuerzos de planificación de la conservación. Los informes publicados de esfuerzos de planificación nacional, multidisciplinaria y de establecimiento de prioridades para la conservación de aves no son comunes. Describo el proceso y los resultados de un taller nacional de planificación para conservación de aves en la República Dominicana que utilizaba un proceso fundamental de base amplia donde creamos una estrategia coordinada para la conservación de aves del país. El proceso de planeación buscaba (1) aumentar comunicación y cooperación entre conservacionistas, (2) familiarizar a los participantes con los recursos disponibles para la conservación de aves, (3) estimular la transferencia de información entre investigadores y manejadores, (4) promover los conceptos del monitoreo de aves a largo plazo, planes de conservación de especies y planes de manejo de especies y (5) desarrollar una estrategia multidisciplinaria común para promover la conservación de aves en la República Dominicana. El taller puso a relieve discusiones de grupo entre investigadores, manejadores, educadores y especialistas en política pública para evaluar las necesidaes y prioridades para la conservación de aves con respecto a cada disciplina, desde entonces se ha estimulado a una porción significativa de la comunidad conservacionista alrededor de proyectos de cooperación que involucran a diversos segmentos de la comunidad. Los ornitólogos pueden jugar un papel significativo en los esfuerzos de conservación mediante una buena disposición para trabajar con personas clave en diversas disciplinas y visualizar de una manera integral y multidisciplinaria las estrategias para abordar asuntos de conservación. [source] Incontinence in the aged: contact dermatitis and other cutaneous consequencesCONTACT DERMATITIS, Issue 4 2007Miranda A. Farage Urinary and faecal incontinence affects a significant portion of the elderly population. The increase in the incidence of incontinence is not only dependent on age but also on the onset of concomitant ageing issues such as infection, polypharmacy, and decreased cognitive function. If incontinence is left untreated, a host of dermatological complications can occur, including incontinence dermatitis, dermatological infections, intertrigo, vulvar folliculitis, and pruritus ani. The presence of chronic incontinence can produce a vicious cycle of skin damage and inflammation because of the loss of cutaneous integrity. Minimizing skin damage caused by incontinence is dependent on successful control of excess hydration, maintenance of proper pH, minimization of interaction between urine and faeces, and prevention of secondary infection. Even though incontinence is common in the aged, it is not an inevitable consequence of ageing but a disorder that can and should be treated. Appropriate clinical management of incontinence can help seniors continue to lead vital active lives as well as avoid the cutaneous sequelae of incontinence. [source] The ,pros' and ,cons' of joint EMS and group certification: a Swedish case studyCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2007Thomas Zobel Abstract Small and medium-sized enterprises (SMEs) are collectively responsible for a significant portion of the total environmental burden worldwide. A common tool used by SMEs to improve their environmental performance is the environmental management system (EMS), which has the disadvantage that it has been developed with larger organizations in mind. A common approach used by Swedish SMEs to facilitate the implementation of an EMS is joint EMS and group certification. This paper evaluates this approach by means of a case study. It is found that the approach is effective for small and micro-sized companies in achieving ISO 14001 certification as fast and cost effectively as possible. A few short cuts including joint environmental policy and objectives and insufficient environmental organization are however threatening to undermine the trustworthiness of the approach. Notwithstanding these flaws, however, it must be concluded that the joint EMS approach is a good alternative for small and micro-sized companies. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment. [source] Influences of the vegetation mosaic on riparian and stream environments in a mixed forest-grassland landscape in "Mediterranean" northwestern CaliforniaECOGRAPHY, Issue 4 2005Hartwell H. Welsh We examined differences in riparian and aquatic environments within the three dominant vegetation patch types of the Mattole River watershed, a 789-km2 mixed conifer-deciduous (hardwood) forest and grassland-dominated landscape in northwestern California, USA. Riparian and aquatic environments, and particularly microclimates therein, influence the distributions of many vertebrate species, particularly the physiologically-restricted ectotherms , reptiles and amphibians (herpetofauna), and fishes. In addition to being a significant portion of the native biodiversity of a landscape, the presence and relative numbers of these more tractable small vertebrates can serve as useful metrics of its "ecological health." Our primary objective was to determine the range of available riparian and aquatic microclimatic regimes, and discern how these regimes relate to the dominant vegetations that comprise the landscape mosaic. A second objective, reported in a companion paper, was to examine relationships between available microclimatic regimes and herpetofaunal distributions. Here we examined differences in the composition, structure, and related environmental attributes of the three dominant vegetation types, both adjacent to and within the riparian corridors along 49 tributaries. Using automated dataloggers, we recorded hourly water and air temperatures and relative humidity throughout the summer at a representative subset of streams; providing us with daily means and amplitudes for these variables within riparian environments during the hottest period. Although the three vegetation types that dominate this landscape each had unique structural attributes, the overlap in plant species composition indicates that they represent a seral continuum. None-the-less, we found distinct microclimates in each type. Only riparian within late-seral forests contained summer water temperatures that could support cold-water-adapted species. We evaluated landscape-level variables to determine the best predictors of water temperature as represented by the maximum weekly maximum temperature (MWMT). The best model for predicting MWMT (adj. R2=0.69) consisted of catchment area, aspect, and the proportion of non-forested (grassland) patches. Our model provides a useful tool for management of cold-water fauna (e.g. salmonids, stream amphibians) throughout California's "Mediterranean" climate zone. [source] SME Entry Mode Choice and Performance: A Transaction Cost PerspectiveENTREPRENEURSHIP THEORY AND PRACTICE, Issue 3 2004Keith D. Brouthers Although small and medium sized enterprises (SMEs) account for a significant portion of international trade, little is know about how they make international entry mode decisions. Transaction cost theory has been widely used to study entry mode selection for large firms. Here we apply the theory to SME mode choices. Further, we set out to determine if SME transaction cost mode choices provide superior performance to other mode choices. We found that transaction cost theory did a good job of explaining SME mode choice and that SMEs that used transaction cost,predicted mode choices performed significantly better than firms using other modes. [source] Nest Crypsis, Reproductive Value of a Clutch and Escape Decisions in Incubating Female Mallards Anas platyrhynchosETHOLOGY, Issue 8 2004Albrecht In cryptically coloured birds, remaining on the nest despite predator approach (risk-taking) may decrease the likelihood that the nest will be detected and current reproductive attempt lost. By contrast, flushing may immediately reveal the nest location to the predator. Escape decisions of incubating parents should therefore be optimized based on the risk-to-parent/cost of escape equilibrium. Animal prey may assess predation risk depending on a variety of cues, including the camouflage that vegetation provides against the predator. We examined interactive effects of nest crypsis and the current reproductive value of a clutch on flushing distances in incubating mallards (Anas platyrhynchos) approached by a human. Our results were consistent with predictions of parental investment theory: flushing distances were inversely correlated with measures of the reproductive value of the current clutch, namely with clutch size, stage of incubation and mean egg volume. Independently of a reproductive value of a clutch, nest concealment explained a significant portion of the variation in flushing distance among females; individual females tended to increase/decrease flushing distances according to change in nest cover. The results further suggest that vegetation concealment greatly influenced the risk of nest detection by local predators, suggesting that vegetation may act as a protective cover for incubating female. A female's ability to delay flushes according to the actual vegetation cover might thus be viewed as an antipredator strategy that reduces premature nest advertising to visually oriented predators. We argue, however, that shorter flying distances from densely covered sites might be maladaptive in areas where a predator's ability to detect incubating female does not rely on visual cues of nests. [source] The Transient Titanocene(II): Direct Synthesis from Solvated Titanium(II) Chloride and Cyclopentadienylsodium and Ensuing Interception with Diphenylacetylene as 1,1-Bis(cyclopentadienyl)-2,3,4,5-tetraphenyltitanacyclopentadiene,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2007John J. Eisch Abstract For the first time the unstable titanocene(II) has been directly synthesized by the Wilkinson metallocene approach, namely the interaction of a THF-soluble form of titanium(II) chloride with two equivalents of cyclopentadienylsodium in THF solution at 0°,25 °C. Because of the transient existence of the titanocene(II) thereby obtained, it could only be chemically trapped in high yield as 1,1-bis(cyclopentadienyl)-2,3,4,5-tetraphenyltitanacyclopentadiene by two equivalents of diphenylacetylene, if the acetylene was added at 25 °C, without removal of the by-product LiCl and NaCl. If the addition of the acetylene was delayed, in order to filter off the LiCl and NaCl from the reaction mixture, then no trace of the titanacyclopentadiene derivative was found upon hydrolytic workup. Instead, a significant portion of the acetylene was found to have undergone hydrotitanation. This finding is clear evidence that the titanocene(II) had undergone a precedented rearrangement to a known dimer having the structure of a titanocene(III) hydride with a fulvalene bridge between the titanium centers. We suggest that the LiCl and NaCl present in the unfiltered reaction mixture form a dichloro complex with titanocene(II) and thereby retard its dimerizing rearrangement to the titanocene(III) hydride. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Membrane orientation of laminin binding proteinFEBS JOURNAL, Issue 18 2003An extracellular matrix bridging molecule of Leishmania donovani Earlier we presented several lines of evidence that a 67-kDa laminin binding protein (LBP) in Leishmania donovani, that is different from the putative mammalian 67-kDa laminin receptor, may play an important role in the onset of leishmaniasis, as these parasites invade macrophages in various organs after migrating through the extracellular matrix. Here we describe the membrane orientation of this Leishmania laminin receptor. Flow cytometric analysis using anti-LBP Ig revealed its surface localization, which was further confirmed by enzymatic radiolabeling of Leishmania surface proteins, autoradiography and Western blotting. Efficient incorporation of LBP into artificial lipid bilayer, as well as its presence in the detergent phase after Triton X-114 membrane extraction, suggests that it may be an integral membrane protein. Limited trypsinization of intact parasite and subsequent immunoblotting of trypsin released material using laminin as primary probe revealed that a major part of this protein harbouring the laminin binding site is oriented extracellularly. Carboxypeptidase Y treatment of the whole cell, as well as the membrane preparation, revealed that a small part of the C-terminal is located in the cytosol. A 34-kDa transmembrane part of LBP could be identified using the photoactive probe, 3-(trifluoromethyl)-3-(m -iodophenyl)diazirine (TID). Partial sequence comparison of the intact protein to that with the trypsin-released fragment indicated that N-terminal may be located extracellularly. Together, these results suggest that LBP may be an integral membrane protein, having significant portion of N-terminal end as well as the laminin binding site oriented extracellularly, a membrane spanning domain and a C-terminal cytosolic end. [source] Liquidity: Considerations of a Portfolio ManagerFINANCIAL MANAGEMENT, Issue 1 2009Laurie Simon Hodrick This paper examines liquidity and how it affects the behavior of portfolio managers, who account for a significant portion of trading in many assets. We define an asset to be perfectly liquid if a portfolio manager can trade the quantity she desires when she desires at a price not worse than the uninformed expected value. A portfolio manager is limited by both what she needs to attain and the ease with which she can attain it, making her sensitive to three dimensions of liquidity: price, timing, and quantity. Deviations from perfect liquidity in any of these dimensions impose shadow costs on the portfolio manager. By focusing on the trade-off between sacrificing on price and quantity instead of the canonical price-time trade-off, the model yields several novel empirical implications. Understanding a portfolio manager's liquidity considerations provides important insights into the liquidity of many assets and asset classes. [source] Short Selling and the Weekend Effect in Nasdaq Stock ReturnsFINANCIAL REVIEW, Issue 1 2009Stephen E. Christophe G10; G11 Abstract We examine daily short selling of Nasdaq stocks to explore whether speculative short selling causes a significant portion of the weekend effect in returns. We identify a weekend effect in speculative short selling whereby it constitutes a larger percentage of trading volume on Mondays versus Fridays. We find an opposite effect in dealer short selling, consistent with market makers adding liquidity and stability. Our main finding is that speculative short selling does not explain an economically meaningful portion of the weekend effect in returns, even among the firms most that are most actively shorted. This finding contradicts some prior studies. [source] Expected Time Value Decay of Options: Implications for Put-Rolling StrategiesFINANCIAL REVIEW, Issue 2 2008George F. Tannous G11; G12; G19; D46 Abstract Assuming the underlying asset price remains constant, previous studies show that the time value of an option decays gradually at a rate that accelerates over time and peaks at the expiration date. Thus, a significant portion of time value is lost in the four weeks leading up to expiration. This paper shows the time value of currently at- or near-the-money options should be expected to decay at a rate that decreases over time. The time values of options that are currently deep-in- or deep-out-of-the-money are expected to initially rise and then resume the normal decay pattern. [source] Work-life balance: Expatriates reflect the international dimensionGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 6 2007Sue Shortland Studies by ORC Worldwide have found that long hours, travel, and other work-related factors intrude into personal lives and create stress for a significant portion of HR professionals and expatriates around the world. But while HR professionals believe work-life balance policies have benefited their organization and themselves, expatriates believe quite the opposite. Given the cost of expatriate assignments and the potential for work-life imbalance to erode employee commitment, organizations can do more to communicate and support work-life practices outside their home country, and to better prepare the expatriate and family for life in their new location. © 2007 Wiley Periodicals, Inc. [source] Disease Progression in Hemodynamically Stable Patients Presenting to the Emergency Department With SepsisACADEMIC EMERGENCY MEDICINE, Issue 4 2010Seth W. Glickman MD Abstract Background:, Aggressive diagnosis and treatment of patients presenting to the emergency department (ED) with septic shock has been shown to reduce mortality. To enhance the ability to intervene in patients with lesser illness severity, a better understanding of the natural history of the early progression from simple infection to more severe illness is needed. Objectives:, The objectives were to 1) describe the clinical presentation of ED sepsis, including types of infection and causative microorganisms, and 2) determine the incidence, patient characteristics, and mortality associated with early progression to septic shock among ED patients with infection. Methods:, This was a multicenter study of adult ED patients with sepsis but no evidence of shock. Multivariable logistic regression was used to identify patient factors for early progression to shock and its association with 30-day mortality. Results:, Of 472 patients not in shock at ED presentation (systolic blood pressure > 90 mm Hg and lactate < 4 mmol/L), 84 (17.8%) progressed to shock within 72 hours. Independent factors associated with early progression to shock included older age, female sex, hyperthermia, anemia, comorbid lung disease, and vascular access device infection. Early progression to shock (vs. no progression) was associated with higher 30-day mortality (13.1% vs. 3.1%, odds ratio [OR] = 4.72, 95% confidence interval [CI] = 2.01 to 11.1; p , 0.001). Among 379 patients with uncomplicated sepsis (i.e., no evidence of shock or any end-organ dysfunction), 86 (22.7%) progressed to severe sepsis or shock within 72 hours of hospital admission. Conclusions:, A significant portion of ED patients with less severe sepsis progress to severe sepsis or shock within 72 hours. Additional diagnostic approaches are needed to risk stratify and more effectively treat ED patients with sepsis. ACADEMIC EMERGENCY MEDICINE 2010; 17:383,390 © 2010 by the Society for Academic Emergency Medicine [source] Hepatitis C virus infection and its clearance alter circulating lipids: Implications for long-term follow-up,HEPATOLOGY, Issue 4 2009Kathleen E. Corey Hepatitis C associated hypolipidemia has been demonstrated in studies from Europe and Africa. In two linked studies, we evaluated the relationship between hepatitis C infection and treatment with lipid levels in an American cohort and determined the frequency of clinically significant posttreatment hyperlipidemia. First, a case-control analysis of patients with and without hepatitis C was performed. The HCV Group consisted of 179 infected patients. The Uninfected Control Group consisted of 180 age-matched controls. Fasting cholesterol, low density lipoprotein (LDL), high density lipoprotein and triglycerides were compared. Next was a retrospective cohort study (Treated Hepatitis C Group) of 87 treated hepatitis C patients with lipid data before and after therapy was performed. In the case-control analysis, the HCV Group had significantly lower LDL and cholesterol than the Uninfected Control Group. In the retrospective cohort, patients in the Treated Hepatitis C Group who achieved viral clearance had increased LDL and cholesterol from baseline compared to patients without viral clearance. These results persisted when adjusted for age, sex, and genotype. 13% of patients with viral clearance had increased LDL and 33% experienced increases in cholesterol to levels warranting lipid lowering therapy. Conclusion: Hepatitis C is associated with decreased cholesterol and LDL levels. This hypolipidemia resolves with successful hepatitis C treatment but persists in nonresponders. A significant portion of successfully treated patients experience LDL and cholesterol rebound to levels associated with increased coronary disease risk. Lipids should be carefully monitored in persons receiving antiviral therapy. (HEPATOLOGY 2009;50:1030,1037.) [source] A feedback suppression algorithm for reliable satellite multicast based on spatial,temporal prediction of the satellite channelINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 2 2009Markos P. Anastasopoulos Abstract The major problem limiting the scalability of large-scale multicast satellite networks is feedback implosion that arises whenever a large number of users simultaneously transmit feedback messages (FBMs) through the network, thus occupying a significant portion of satellite system resources. In satellite networks operating above 10,GHz, attenuation due to rain constitutes the dominant fading mechanism deteriorating the quality of service. In this paper, a novel scheme for providing large-scale reliable multicast services through a star-based geostationary satellite topology is presented incorporating accurate channel modeling of the propagation phenomena. The new protocol is based on the selection of an area representative that provides quick FBMs aiming at suppressing FBMs originating from the rest of the network users. The scheme provides a timely reaction to changes of either the channel conditions or the network topology by properly updating the selection of representatives. Through appropriate simulations, comparisons and examples it is demonstrated that the new approach suppresses FBMs very effectively. Copyright © 2009 John Wiley & Sons, Ltd. [source] How do Individual, Institutional, and Foreign Investors Win and Lose in Equity Trades?INTERNATIONAL REVIEW OF FINANCE, Issue 3-4 2006Evidence from Japan ABSTRACT We investigate the gains and losses from equity trades of individual investors, various institutional investors, and foreign investors in the Tokyo Stock Exchange. We develop a trade-weighted performance measure and examine the impact of trading intervals, price spreads, and market timing on performance. We find that different investor types gain or lose from different sources. For example, we discover that individual investors have poor market timing ability but potentially gain during short-run trading intervals as their average sell price is consistently higher than the average purchase price. In contrast, we find that foreign investors consistently generate gains from trade due to good market timing, although their average sell price is lower than the average purchase price. Also, we find that foreign investors extract significant portion of their gains by trading against Japanese institutional investors when Japanese investors trade before their fiscal-year end. [source] Aggregate Earnings and Asset PricesJOURNAL OF ACCOUNTING RESEARCH, Issue 5 2009RAY BALL ABSTRACT A principal-components analysis demonstrates that common earnings factors explain a substantial portion of firm-level earnings variation, implying earnings shocks have substantial systematic components and are not almost fully diversifiable as prior literature has concluded. Furthermore, the principal components of earnings and returns are highly correlated, implying aggregate earnings risks and return risks are related. In contrast to previous studies, the correlation we report between the systematic components of earnings and returns is stable over time. We also show that the earnings factors are priced, in the sense that the sensitivities of securities' returns to the earnings factors explain a significant portion of the cross-sectional variation in returns, even controlling for return risk. This suggests earnings performance is an underlying source of priced risk. Our evidence that the information sets of returns and earnings are jointly determined implies cash flow risk and return risk are not fully separable, and raises the possibility that it is the common variation of earnings and returns that is priced. [source] The Philippine Land Reform in Comparative Perspective: Some Conceptual and Methodological ImplicationsJOURNAL OF AGRARIAN CHANGE, Issue 1 2006SATURNINO M. BORRAS JR Using empirical evidence from the Philippine land reform (1972,2005), this paper examines land reform theory and practice, and argues that convention has a priori excluded a significant portion of actually existing land-based production and distribution relationships, while it has inadvertently included in its definition and analysis land transfers that do not constitute real redistributive reform. This problematic framing of ,exclusion,inclusion' has led to incorrect accounting and analysis of the nature, scope, pace and direction of change/reform that have occurred (or not) in the agrarian structure of a particular setting. This problem has prevented the emergence of nuanced comparative land reform studies, with possible further implications for studies that attempt to trace causal relationships between land redistribution and agrarian transformation. [source] Quality and Outcomes of Heart Failure Care in Older Adults: Role of Multidisciplinary Disease-Management ProgramsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2002Ali Ahmed MD, FACP PURPOSE: To determine whether the management of heart failure by specialized multidisciplinary heart failure disease-management programs was associated with improved outcomes. BACKGROUND: The advent of angiotensin-converting enzyme inhibitors, beta-blockers, and spironolactone has revolutionized the management of heart failure. Randomized double-blind studies have demonstrated survival benefits of these drugs in heart failure patients. Nevertheless, in spite of these advances, heart failure continues to be a syndrome of poor outcomes.1,4 There is also evidence that a significant portion of heart failure patients does not receive this evidence-based therapy that reduces morbidity and mortality.5,7 Various disease-management programs have been proposed and tested to improve the quality of heart failure care. Most of these programs are specialized multidisciplinary heart failure clinics lead by cardiologists or heart failure specialists and conducted by nurses or nurse practitioners. Similar to the Department of Veterans Affairs (VA) multidisciplinary geriatric assessment clinics, these clinics also use many other services, including pharmacists, dietitians, physical therapists, and social workers. Some of these programs also have an affiliated home health service. Several observation studies, using mostly pre- and postcomparison designs, have demonstrated the effectiveness of these programs in the process of care, resource use, healthcare costs, and clinical outcomes in patients with heart failure.8 Risk of hospitalization was reduced by 50% to 85% in six of the studies.8 Subsequently, several randomized trials were conducted to determine the effectiveness of these programs. The purpose of this systematic review was to determine the effectiveness of these programs on mortality and hospitalization rates of heart failure patients. METHODS: Published articles on human randomized trials involving specialized heart failure disease-management programs in all languages were searched using Medline from 1966 to 1999 and other online databases using the following terms and Medical Subject Headings: case management (exp); comprehensive health care (exp); disease management (exp); health services research (exp); home care services (exp); clinical protocols (exp); patient care planning (exp); quality of health care (exp); nurse led clinics; special clinics; and heart failure, congestive (exp). In addition, a manual search of the bibliographies of searched articles was performed to identify articles otherwise missed in the above search. Personal communications were made with three authors to obtain further data on their studies. Using a data abstraction tool, two of the investigators separately abstracted data from the selected articles. Data from the selected studies were combined using the DerSimonian and Laird random effects model and the Mantel-Haenszel-Peto fixed effects model. Meta-Analyst 0.998 software (J. Lau, New England Medical Center, Boston, MA) was used to determine risk ratios (RRs) with 95% confidence intervals (CIs) of mortality and hospitalization for patients receiving care through these specialized programs compared with those receiving usual care. The Cochran Q test was used to test heterogeneity among the studies, and sensitivity analyses were performed to examine the effect of various covariates, such as duration of intervention, and other characteristics of the disease-management programs. RESULTS: The original search resulted in 416 published articles, of which 35 met preliminary selection criteria. Of these, 11 were randomized trials and were selected for the meta-analysis. Studies that were not randomized trials, did not involve heart failure patients or disease-management programs, or had missing outcomes were excluded. Of the 11 studies selected, nine involved specialized follow-up using multidisciplinary teams and the remaining two involved follow-up by primary care physicians and telephone. These studies involved 1,937 heart failure patients with a mean age of 74. The follow-up period ranged from no follow-up (one study) to 1 year (one study). Patients receiving care from specialized heart failure disease-management programs had a 13% lower risk of hospitalization than those receiving usual care (summary RR = 0.87; 95% CI = 0.79,0.96), but the Cochran Q test demonstrated significant heterogeneity among the studies (P = .003). Subgroup analysis of the nine studies using specialized follow-up by a multidisciplinary team showed similar results (summary RR = 0.77, 95% CI = 0.68,0.86; test of heterogeneity, P> .50). Seven of the nine studies did not show any significant association between intervention and reduced hospitalization, but the two studies that used follow up by primary care physicians and telephone failed to show any significant reduction in hospitalization (summary RR = 0.94, 95% CI = 0.75,1.19). In fact, one of the studies demonstrated a higher risk of hospitalization for patients receiving intervention (RR = 1.26, 95% CI = 1.04,1.52). Of the 11 studies, only six reported mortality as an outcome. None of these studies found any association between intervention and mortality (summary RR = 1.15, 95% CI = 0.96,1.37; test of heterogeneity, P> .15). Five of the studies used quality of life or functional status as outcomes, and, of them, only one demonstrated significant positive association. The results of the sensitivity analyses were negative for any significant association with duration of intervention or follow-up or year of study. Eight studies performed cost analyses and seven demonstrated cost-effectiveness of the intervention. CONCLUSIONS: The authors concluded that specialized disease-management programs were cost-effective, and heart failure patients cared for by these programs were more likely to undergo fewer hospitalizations, but the study did not provide any conclusive association between these programs and quality of care or mortality. The authors recommend that disease-management programs involve patient education and specialized follow-up by a multidisciplinary team including home health care. [source] Phylogenetic analysis of intestinal bacteria in the Chinese mitten crab (Eriocheir sinensis)JOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2007K. Li Abstract Aims:, To identify the dominant intestinal bacteria in the Chinese mitten crab, and to investigate the differences in the intestinal bacteria between pond-raised and wild crabs. Methods and Results:, The diversity of intestinal bacteria in the Chinese mitten crabs was investigated by denaturing gradient gel electrophoresis (DGGE) fingerprinting, 16S rRNA gene clone library analysis and real-time quantitative PCR. The principal component analysis of DGGE profiles indicated that substantial intersubject variations existed in intestinal bacteria in pond-raised crab. The sequencing of 16S rRNA genes revealed that 90,95% of the phylotypes in the clone libraries were affiliated with Proteobacteria and Bacteroidetes. Some genera were identified as unique in wild crabs and in pond-raised crabs, whereas Bacteroidetes was found to be common in all sampled crab groups. Real-time quantitative PCR indicated that the abundance of Bacteroides and the total bacterial load were approximately four-to-10 times higher in pond-raised crabs than in wild crabs. A significant portion of the phylotypes shared low similarity with previously sequenced organisms, indicating that the bacteria in the gut of Chinese mitten crabs are yet to be described. Conclusions:, The intestinal bacteria of pond-raised crabs showed higher intersubject variation, total diversity and abundance than that observed in wild crabs. The high proportion of the clones of Proteobacteria and Bacteroidetes in the clone library is an indication that these bacteria may be the dominant population in the gut of the Chinese mitten crab. Significance and Impact of the Study:, This study demonstrated obvious differences in the intestinal bacterial composition of pond-raised crabs and wild crabs. This knowledge will increase our understanding of the effects of aquaculture operations on bacterial community composition in the crab gut and provide necessary data for the development of probiotic products for crab cultivation. [source] Option Market Efficiency and Analyst RecommendationsJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 5-6 2010James S. Doran Abstract:, This paper examines the information content in option markets surrounding analyst recommendation changes. The sample includes 6,119 recommendation changes for optionable stocks over the period January 1996 through December 2005. As expected, mean underlying asset returns are positive (negative) on days of recommendation upgrades (downgrades). However, volatility levels and shifts prior to recommendation changes explain a significant portion of underlying asset price responses. Ex-ante price and volatility responses in option markets are linked to increased jump uncertainty risk premia. Our findings suggest information in option markets leads analyst recommendation changes, implying revisions contain less information than previously thought. [source] Anatomy and Physiology of the Right Interganglionic Nerve: Implications for the Pathophysiology of Inappropriate Sinus TachycardiaJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2008JING ZHOU M.D. Objective: To simulate inappropriate sinus tachycardia (IST) in experimental animals. Background: We recently found that epinephrine injected into the anterior right ganglionated plexi (ARGP) adjacent to the sinoatrial (SA) node induced an arrhythmia simulating IST. Methods: In 19 anesthetized dogs, via a right thoracotomy, the course of the interganglionic nerve (IGN) from the right stellate ganglion along the superior vena cava to the heart was delineated. High-frequency stimulation (HFS; 0.1 msec duration, 20 Hz, 4.5,9.3 V) was applied to IGN at the junction of innominate vein and SVC. Results: HFS of the IGN significantly increased the sinus rate (SR) (baseline: 156 ± 19 beats/minutes [bpm], 4.5 V: 191 ± 28 bpm*, 8.0 V: 207 ± 23 bpm*, 9.3 V: 216 ± 18 bpm*; *P < 0.01 compared to baseline) without significant changes in A-H interval or blood pressure. P-wave morphology, ice mapping, and noncontact mapping indicated that this tachycardia was sinus tachycardia. In 8 of 19 dogs, injecting hexamethonium (5 mg), a ganglionic blocker, into the ARGP attenuated the response elicited by IGN stimulation (baseline: 160 ± 21 bpm, 4.5 V: 172 ± 32 bpm, 8.0 V: 197 ± 32 bpm*, 9.3 V: 206 ± 26 bpm*; *P < 0.05 compared to baseline). In 19 of 19 animals, after formaldehyde injection into the ARGP, SR acceleration induced by IGN stimulation was markedly attenuated (baseline: 149 ± 17 bpm, 4.5 V: 151 ± 21 bpm, 8.0 V: 155 ± 23 bpm, 9.3 V: 167 ± 24 bpm*; *P < 0.05 compared to baseline). Conclusions: HFS of the IGN caused a selective and significant acceleration of the SR. A significant portion of IGN traverses the ARGP or synapses with the autonomic ganglia in the ARGP before en route to the SA node. Dysautonomia involving the IGN and/or ARGP may play an important role in IST. [source] Investigation of multiphase hydrogenation in a catalyst-trap microreactorJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 3 2009S. McGovern BACKGROUND: Multiphase hydrogenation plays a critical role in the pharmaceutical industry. A significant portion of the reaction steps in a typical fine chemical synthesis are catalytic hydrogenations, generally limited by resistances to mass and heat transport. To this end, the small-scale and large surface-to-volume ratios of microreactor technology would greatly benefit chemical processing in the pharmaceutical and other industries. A silicon microreactor has been developed to investigate mass transfer in a catalytic hydrogenation reaction. The reactor design is such that solid catalyst is suspended in the reaction channel by an arrangement of catalyst traps. The design supports the use of commercial catalyst and allows control of pressure drop across the bed by engineering the packing density. RESULTS: This paper discusses the design and operation of the reactor in the context of the liquid-phase hydrogenation of o-nitroanisole to o-anisidine. A two-phase ,flow map' is generated across a range of conditions depicting three flow regimes, termed gas-dominated, liquid-dominated, and transitional, all with distinctly different mass transfer behavior. Conversion is measured across the flow map and then reconciled against the mass transfer characteristics of the prevailing flow regime. The highest conversion is achieved in the transitional flow regime, where competition between phases induces the most favorable gas,liquid mass transfer. CONCLUSION: The results are used to associate a mass transfer coefficient with each flow regime to quantify differences in performance. This reactor architecture may be useful for catalyst evaluation through rapid screening, or in large numbers as an alternative to macro-scale production reactors. Copyright © 2008 Society of Chemical Industry [source] Ophthalmically Administered , Blockers and Their Cardiopulmonary EffectsJOURNAL OF CLINICAL HYPERTENSION, Issue 3 2001Domenic A. Sica MD Early clinical studies revealed that timolol and other topical , blockers were effective in reducing intra-ocular pressure, without the side effects associated with other antiglaucoma agents. However, because persons with cardiovascular or respiratory diseases were generally excluded from many of these early studies, the risk of serious cardiovascular and respiratory side effects was seriously underestimated. Once these drugs were made available to the general population, reports of systemic side effects began to proliferate. Very quickly, adverse effects from topical , blockade became "old news." Despite this recognition, many treating physicians remained unaware of the potential for systemic , blockade from topically applied , blockers. A significant portion of a topically administered dose of a , blocker can be absorbed and thereby affect systemic , blockade. Sensitivity to systemic , blockade can be quite dramatic in certain highly susceptible patients, particularly those with either cardiac or pulmonary abnormalities. Careful review of patients' medications will generally lessen, but not completely eliminate, the risk of undesired complications attributable to topical P blockade. [source] Evidence of an Interaction Involving Complexity and Coupling as Predicted by Normal Accident TheoryJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 3 2007Frederick Wolf This paper describes a test of the principle hypothesis of Normal Accident Theory. It posits and tests for the existence of an interaction involving interactive complexity and coupling associated with in an important class of manufacturing organizations. Ninety four (n=94) petroleum refineries located in the United States during the five-year period 1993,97 were examined. The dependent variable in this test was the ratio of Reportable Quantity accidental hazardous chemical releases per unit of production. Refinery capacity and age were included as control variables. This study identified a statistically significant interaction involving interactive complexity and coupling, as predicted by Normal Accident Theory. The interaction appears to be consistent with an important core hypothesis of normal accident theory over a significant portion of its domain. The nature of this interaction and its potential relevance to organizational sense making is discussed. Additional opportunities for quantitative research involving Normal Accident Theory are identified. [source] Appropriate utilization of hospital beds in internal medicine: evaluation in a tertiary care hospitalJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2007Ömer Dizdar MD Abstract Aim, To assess the appropriateness of utilization of beds in the internal medicine department of a university hospital. Methods, The appropriateness of hospital stay was evaluated using the Appropriateness Evaluation Protocol. A random sample of 402 days of stay was assessed. Results, One hundred and thirty-nine days of stay (34.6%) were classified as inappropriate. The inappropriate stays were mostly secondary to hospital-related factors. The two major factors for inappropriate stays were ,inappropriate timing/delay in diagnostic procedures/consultations' (27%) and ,delay in obtaining test results' (27%). None of the factors including age, gender, residence and inpatient period was significantly related to inappropriate stay in univariate analysis. Conclusion, This study indicated that a significant portion of stays were inappropriate. Efforts to decrease particularly hospital-related factors associated with inappropriate stay are needed. [source] Equity Valuation and Current Cost Disclosures: the Case of MexicoJOURNAL OF INTERNATIONAL FINANCIAL MANAGEMENT & ACCOUNTING, Issue 3 2001Paquita Y. Davis-Friday This study uses an accounting-based valuation model to investigate the relation between the market value of publicly traded Mexican firms and their disclosures of price-level adjusted accounting information. The model is estimated on a sample of Mexican companies during 1987,1990, when annual inflation rates in Mexico decreased from 130 per cent to 20 per cent. The results indicate that general price level-adjusted and current cost disclosures explain a significant portion of the cross-sectional variation in the market-to-book ratios of the sample firms. Further, the explanatory power of holding gains is robust to decreases in the general level of inflation, which suggests that current cost and constant peso disclosures are relevant for determining firm value over a wide range of inflation rates. These results are particularly important now since the Mexican Institute of CPAs has proposed eliminating the measurement of holding gains in order to make Mexican financial statements more comparable to US and Canadian GAAP. [source] | ||||||||||||||||||||||||||||||||||||||||||||||