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High Cost (high + cost)
Kinds of High Cost Selected AbstractsBacterial motility: links to the environment and a driving force for microbial physicsFEMS MICROBIOLOGY ECOLOGY, Issue 1 2006James G. Mitchell Abstract Bacterial motility was recognized 300 years ago. Throughout this history, research into motility has led to advances in microbiology and physics. Thirty years ago, this union helped to make run and tumble chemotaxis the paradigm for bacterial movement. This review highlights how this paradigm has expanded and changed, and emphasizes the following points. The absolute magnitude of swimming speed is ecologically important because it helps determine vulnerability to Brownian motion, sensitivity to gradients, the type of receptors used and the cost of moving, with some bacteria moving at 1 mm s,1. High costs for high speeds are offset by the benefit of resource translocation across submillimetre redox and other environmental gradients. Much of environmental chemotaxis appears adapted to respond to gradients of micrometres, rather than migrations of centimetres. In such gradients, control of ion pumps is particularly important. Motility, at least in the ocean, is highly intermittent and the speed is variable within a run. Subtleties in flagellar physics provide a variety of reorientation mechanisms. Finally, while careful physical analysis has contributed to our current understanding of bacterial movement, tactic bacteria are increasingly widely used as experimental and theoretical model systems in physics. [source] Computer adoption and returns in transitionTHE ECONOMICS OF TRANSITION, Issue 1 2007Yemisi Kuku O; P2; J31 Abstract Across nine transition economies, it is the young, educated, English-speaking workers with the best access to local telecommunications infrastructures who work with computers. These workers earn about 25 percent more than do workers of comparable observable skills who do not use computers. Controlling for likely simultaneity between computer use at work and labour market earnings makes the apparent returns to computer use disappear. These results are corroborated using Russian longitudinal data on earnings and computer use on the job. High costs of computer use in transition economies suppress wages that firms can pay to their workers who use computers. [source] Multiple animated characters motion fusionCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 5 2002Luo Zhongxiang Abstract One of the major problems of the motion capture-based computer animation technique is the relatively high cost of equipment and low reuse rate of data. To overcome this problem, many motion-editing methods have been developed. However, most of them can only handle one character whose motions are preset, and hence cannot interact with its environment automatically. In this paper, we construct a new architecture of multiple animated character motion fusion, which not only enables the characters to perceive and respond to the virtual environment, but also allows them to interact with each other. We will also discuss in detail the key issues, such as motion planning, coordination of multiple animated characters and generation of vivid continuous motions. Our experimental results will further testify to the effectiveness of the new methodology. Copyright © 2002 John Wiley & Sons, Ltd. [source] Facilitating process control teaching and learning in a virtual laboratory environmentCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 2 2002T. Murphy Abstract The rapid pace of technological developments and the high cost of engineering equipment, pose several challenges to traditional modes of engineering education. Innovations in education are desirable. In particular, education on practical aspects of engineering and personnel training can be enhanced through the use of virtual laboratories. Such educative experiences allow a student to better understand the theoretical aspects of the discipline in addition to its integration with practical knowledge. In this work, the development, set-up and application of a virtual twin heat exchanger plant is described. The philosophy and methodology of our approach is described, including the implementation details and our experience in using it. The effectiveness of the platform in educating students and in training industrial personnel is described. © 2002 Wiley Periodicals, Inc. Comput Appl Eng Educ 10: 79,87, 2002; Published online in Wiley InterScience (www.interscience.wiley.com.); DOI 10.1002/cae.10011 [source] Towards an autonomic approach for edge computingCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 14 2007Mikael Desertot Abstract Nowadays, one of the biggest challenges for companies is to cope with the high cost of their information technologies infrastructure. Edge computing is a new computing paradigm designed to allocate on-demand computing and storage resources. Those resources are Web cache servers scattered over the ISP backbones. We argue that this paradigm could be applied for on-demand full application hosting, helping to reduce costs. In this paper, we present a J2EE (Java Enterprise Edition) dynamic server able to deploy/host J2EE applications on demand and its autonomic manager. For this, we reengineer and experiment with JOnAS, an open-source J2EE static server. Two management policies of the autonomic manager were stressed by a simulation of a worldwide ISP network. Copyright © 2006 John Wiley & Sons, Ltd. [source] Pt immobilization on TiO2 -embedded carbon nanofibers using photodepositionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2010S. Kim Abstract Currently, the use of fuel cell electrodes containing Pt catalysts has been limited due to technological problems in this system, primarily the system's high cost. The improvement of Pt catalyst use has been achieved by changes in the Pt immobilization method. In this study, we have studied Pt immobilization on carbon nanofiber composites using the photodeposition method. First, we prepared the carbon nanofibers, which were homogeneously embedded TiO2 using the electrospinning technology. These TiO2 -embedded carbon nanofiber composites (TiO2/CNFs) were then immersed in a Pt precursor solution and irradiated with UV light. The obtained Pt-deposited TiO2/CNFs contained Pt that was immobilized on the carbon nanofibers, and the Pt particle size was 2-5 nm. The XPS spectra showed that the amount of Pt increased with an increasing UV irradiation time. The current densities and total charge also increased with an increase in the UV irradiation time, possibly due to an increase of active specific area by finely dispersed Pt nanoparticles. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Evaluation of a single-platform microcapillary flow cytometer for enumeration of absolute CD4+ T-lymphocyte counts in HIV-1 infected Thai patients,,CYTOMETRY, Issue 5 2007Kovit Pattanapanyasat Abstract Background: Various assays are used to enumerate peripheral blood absolute CD4+ T-lymphocytes. Flow cytometry is considered the gold standard for this purpose. However, the high cost of available flow cytometers and monoclonal antibody reagents make it difficult to implement such methods in the resource-poor settings. In this study, we evaluated a cheaper, recently developed single-platform microcapillary cytometer for CD4+ T-lymphocyte enumeration, the personal cell analyzer (PCA), from Guava® Technologies. Methods: CD4+ and CD8+ T-lymphocyte counts in whole blood samples from 250 HIV-1 infected Thais were determined, using a two-color reagent kit and the Guava PCA, and compared with the results obtained with two reference microbead-based methods from Becton Dickinson Biosciences: the three-color TruCOUNTÔ tube method and the two-color FACSCountÔ method. Statistical correlations and agreements were determined using linear correlation and Bland,Altman analysis. Results: Absolute CD4+ T-lymphocyte counts obtained using the Guava PCA method highly correlated with those obtained using TruCOUNT method (R2 = 0.95, mean bias +13.1 cells/,l, limit of agreement [LOA] ,101.8 to +168.3 cells/,l). Absolute CD8+ T-lymphocyte counts obtained using the Guava PCA method also highly correlated with those obtained with the two reference methods (R2 = 0.92 and 0.88, respectively). Conclusion: This study shows that the enumeration of CD4+ T-lymphocytes using the Guava microcapillary cytometer PCA method performed well when compared with the two reference bead-based methods. However, like the two reference methods, this new method needs substantial technical expertise. © 2007 Clinical Cytometry Society. [source] How Special Are Rural Areas?DEVELOPMENT POLICY REVIEW, Issue 4 2001The Economic Implications of Location for Rural Development Despite on-going change, rural areas remain characterised by relative abundance of natural capital, and by distance and the relatively high cost of movement. They are also home to most of the world's poor. Compared with urban areas which enjoy proximity to customers and producers, rural areas may have comparative advantage only in primary activities based on immobile natural resources and closely related activities. There are differences, however, between ,peri-urban', ,middle countryside' and ,remote' areas. In some areas, economic growth, urban expansion, and improved transport and communications create new urban-oriented opportunities for rural services and labour. Remote areas will continue to present special difficulties, however; and, in general, the potential for non-agricultural diversification is less than is sometimes argued. [source] Issues related to the diagnosis and treatment of autism spectrum disorders,DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2007Paul T. Shattuck Abstract This paper explores issues and implications for diagnosis and treatment, stemming from the growing number of children identified with autism spectrum disorders (ASDs). Recent developments and innovations in special education and Medicaid programs are emphasized. Eligibility determination policies, innovations in diagnostic practices, the cost and financing of assessment, variability among programs in diagnostic criteria, and racial/ethnic disparities in the timing of diagnosis all influence the capacity of service systems to provide diagnoses in a timely, coordinated, accurate, economical, and equitable manner. There are several barriers to the more widespread provision of intensive intervention for children with ASDs, including lack of strong evidence of effectiveness in scaled-up public programs, uncertainty about the extent of obligations to provide services under the Individuals with Disabilities Education Act, high cost of intervention, and variability among states in their willingness to fund intensive intervention via Medicaid. Innovative policy experiments with respect to financing intensive intervention through schools and Medicaid are being conducted in a number of states. © 2007 Wiley-Liss, Inc. MRDD Research Reviews 2007;13:129,135. [source] Matching Response to Context in Complex Political Emergencies: ,Relief', ,Development', ,Peace-building' or Something In-between?DISASTERS, Issue 4 2000Philip White There is an ongoing debate over the value and pitfalls of the policy and practice of ,linking relief and development' or ,developmental relief' in aid responses to complex political emergencies (CPEs). Driven by concerns about relief creating dependence, sometimes doing harm and failing to address root causes of emergencies despite its high cost, pursuit of both relief and development has become a dominant paradigm among international aid agencies in CPEs as in ,natural' disasters. In CPEs a third objective of ,peace-building' has emerged, along with the logic that development can itself help prevent or resolve conflict and sustain peace. However, this broadening of relief objectives in ongoing CPEs has recently been criticised on a number of counts, central concerns being that it leads to a dilution of commitment to core humanitarian principles and is overly optimistic. This paper addresses these issues in the light of two of the CPEs studied by the COPE project: Eritrea and Somalia/Somaliland. It is argued that the debate has so far suffered from lack of clarity about what we mean by ,relief', ,development' and, for that matter, ,rehabilitation' and ,peace-building'. The wide spectrum of possible aid outcomes does not divide neatly into these categories. The relief,development divide is not always as clear-cut, technically or politically, as the critics claim. Moreover such distinctions, constructed from the point of view of aid programmers, are often of little relevance to the concerns of intended beneficiaries. Second, there has been insufficient attention to context: rather than attempting to generalise within and across CPE cases, a more productive approach would be to examine more closely the conditions under which forms of aid other than basic life support can fruitfully be pursued. This leads to consideration of collective agency capacity to respond effectively to diverse needs in different and changing circumstances. [source] Opportunities and constraints in the adaptation of technology for the diagnosis of bacterial plant diseases , experience from Tanzania,EPPO BULLETIN, Issue 3-4 2000R. Black In order to improve diagnostic services and plant quarantine capabilities in Tanzania, the techniques of semi-selective media, the BACTID system, metabolic profiling (Biolog), indirect enzyme-linked immunosorbent assays (ELISA) and polymerase chain reaction (PCR) were assessed for suitability with the existing facilities for the diagnosis and detection of plant-pathogenic bacteria of vegetables. Field-collected samples as well as farmers' own and commercial germplasm were used in studies involving Ralstonia solanacearum, Clavibacter michiganensis subsp. michiganensis and Xanthomonas campestris pv. vesicatoria in Solanaceae and X. c. pv. campestris in Brassicaceae. Each of the techniques was used successfully with one or more of the target pathogens; each had advantages depending on the speed, sensitivity and specificity required, as well as the costs of carrying out the diagnosis. However, constraints emerged relating to the use and disposal of materials such as plastic Petri dishes and toxic substances. The more familiar underlying constraints of high cost and poor availability of consumables and erratic water and electricity supply continued to present problems. These problems will be discussed in relation to the development of an integrated and sustainable approach to the provision of routine diagnostic services. [source] Spill-over effects of intermittent costs for defection in social dilemmasEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 6 2002Daniel Eek This research investigates the role of intermittent monetary costs in restraining individuals from defection in social dilemmas. In Experiment 1, 104 car owners made fictitious choices between a slow and a fast travel mode in the context of a continuous social dilemma. There were four different conditions of monetary costs for choosing the fast mode (defection): no cost, low cost, high cost to self, or high cost to others. Participants defected most when there was no cost and least when they themselves were charged a high cost. A spill-over effect was obtained such that when others were charged a high cost to defect, defection rates were lower than under no cost. Experiment 2 used 36 undergraduates as participants in an iterated decision task with real groups. The results replicated the major results of Experiment 1. Furthermore, whereas prosocials were strongly affected by intermittent costs for defection (i.e. showed large spill-over effects), proselfs seemed to be unaffected. Possible explanations of this interaction effect between social value orientation and intermittent punishment for defection are provided. Copyright © 2002 John Wiley & Sons, Ltd. [source] Non-superconducting fault current limitersEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 5 2009M. Tarafdar Hagh Abstract This paper proposes the use of non-superconducting DC reactor type fault current limiter (NSFCL) instead of superconducting fault current limiters (SFCLs) which has high cost and technology. Proposed FCL consists of three similar sets, each including a diode bridge and a single non-superconducting DC reactor. The device is connected in series with distribution line and it has almost no effect on the normal system operation. It is not necessary to use a control circuit and it has a simple and cheap power circuit. Design characteristics, analytical analysis and overall transient and steady-state performance of NSFCL in normal and fault conditions are presented in this paper. The comparison between experimental and simulation results indicate good agreements. The results confirm that the power loss of NSFCL is a very small percentage of distribution line power. Also, the system current and load voltage distortions due to using NSFCL is explained and simulated. Copyright © 2008 John Wiley & Sons, Ltd. [source] Certolizumab pegol: a new option for rheumatoid arthritisFUTURE PRESCRIBER, Issue 4 2009MSc Rheumatology SpR, Margaret HY Ma MBBS Rheumatoid arthritis (RA) presents a significant burden to healthcare in the UK. New biological therapies have advanced treatment but at a high cost to the NHS. Certolizumab pegol is a new TNF inhibitor, providing an additional treatment option for RA. In this article Dr Ma and Dr Choy consider the efficacy of certolizumab pegol, and where it may fit into the RA armoury. Copyright © 2009 John Wiley & Sons, Ltd. [source] How a major multinational is working to overcome the barriers to improved expatriate ROIGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 3 2008Yvonne McNulty Despite the growing use of international assignments and the high cost of expatriates, few global firms have found the key to gauging the success of their mobility program, especially their expatriate return on investment (ROI). The author reports on one global firm that has made great strides towards a practical ROI tool by targeting the fundamental systems and processes needed to manage international assignments. The author also makes the case that an assignment's purpose, relative to business and/or organizational strategies, determines the types of inputs and outcomes to measure; and that ROI determinations for expatriates must include intangible and long-term benefits and costs. © 2008 Wiley Periodicals, Inc. [source] Quantifying uncertainty in estimates of C emissions from above-ground biomass due to historic land-use change to cropping in AustraliaGLOBAL CHANGE BIOLOGY, Issue 8 2001Damian J. Barrett Abstract Quantifying continental scale carbon emissions from the oxidation of above-ground plant biomass following land-use change (LUC) is made difficult by the lack of information on how much biomass was present prior to vegetation clearing and on the timing and location of historical LUC. The considerable spatial variability of vegetation and the uncertainty of this variability leads to difficulties in predicting biomass C density (tC ha,1) prior to LUC. The issue of quantifying uncertainties in the estimation of land based sources and sinks of CO2, and the feasibility of reducing these uncertainties by further sampling, is critical information required by governments world-wide for public policy development on climate change issues. A quantitative statistical approach is required to calculate confidence intervals (the level of certainty) of estimated cleared above-ground biomass. In this study, a set of high-quality observations of steady state above-ground biomass from relatively undisturbed ecological sites across the Australian continent was combined with vegetation, topographic, climatic and edaphic data sets within a Geographical Information System. A statistical model was developed from the data set of observations to predict potential biomass and the standard error of potential biomass for all 0.05° (approximately 5 × 5 km) land grid cells of the continent. In addition, the spatial autocorrelation of observations and residuals from the statistical model was examined. Finally, total C emissions due to historic LUC to cultivation and cropping were estimated by combining the statistical model with a data set of fractional cropland area per land grid cell, fAc (Ramankutty & Foley 1998). Total C emissions from loss of above-ground biomass due to cropping since European colonization of Australia was estimated to be 757 MtC. These estimates are an upper limit because the predicted steady state biomass may be less than the above-ground biomass immediately prior to LUC because of disturbance. The estimated standard error of total C emissions was calculated from the standard error of predicted biomass, the standard error of fAc and the spatial autocorrelation of biomass. However, quantitative estimates of the standard error of fAc were unavailable. Thus, two scenarios were developed to examine the effect of error in fAc on the error in total C emissions. In the first scenario, in which fAc was regarded as accurate (i.e. a coefficient of variation, CV, of fAc = 0.0), the 95% confidence interval of the continental C emissions was 379,1135 MtC. In the second scenario, a 50% error in estimated cropland area was assumed (a CV of fAc = 0.50) and the estimated confidence interval increased to between 350 and 1294 MtC. The CV of C emissions for these two scenarios was 25% and 29%. Thus, while accurate maps of land-use change contribute to decreasing uncertainty in C emissions from LUC, the major source of this uncertainty arises from the prediction accuracy of biomass C density. It is argued that, even with large sample numbers, the high cost of sampling biomass carbon may limit the uncertainty of above-ground biomass to about a CV of 25%. [source] Prophylactic recombinant factor VIIa in haemophilia patients with inhibitorsHAEMOPHILIA, Issue 3 2005G. Young Summary., Prevention of bleeding, especially into joints, with prophylactic factor infusions is the most effective treatment for severe haemophilia patients. Approximately 15,30% of patients with factor VIII deficiency and 3,5% of patients with factor IX deficiency develop neutralizing antibodies (inhibitors) to factor precluding their use. Such patients often have significant bleeding complications including life- and limb-threatening bleeds and severe joint disease. Prophylaxis for such patients is not generally considered because of the fact that the standard (bypassing) agents for such patients are not as effective as natural factor replacement, because of concerns for thrombotic complications and also because of the very high cost of bypassing agents. We treated two patients with high titre inhibitors with prophylactic recombinant factor VIIa (rFVIIa). The first patient was treated as a result of development of a target joint and to reduce the use of agents that can lead to anamnesis of his inhibitor. The second patient had multiple severe bleeds and was hospitalized 20% of the time over a 2-year period. He had a very poor quality of life. Both patients had shown good responses previously to rFVIIa for treatment of bleeds. Both patients had an outstanding response to prophylaxis albeit at a very high cost. Prophylaxis with rFVIIa can be an effective approach in select inhibitor patients with severe complications related to bleeding. [source] Thawed cryoprecipitate stored for 6 h at room temperature: a potential alternative to factor VIII concentrate for continuous infusionHAEMOPHILIA, Issue 6 2004L. M. B. Pesquera-Lepatan Summary., Continuous infusion (CI) of factor VIII concentrates has been demonstrated to be cost-effective method in maintaining stable levels of FVIII activity in haemophilia A patients with major bleeding or undergoing major surgery. Cryoprecipitates remain the major source of FVIII in developing countries-like the Philippines because of limited availability and high cost of concentrates. To support the use of cryoprecipitate as alternative to FVIII concentrate for CI in centres with no factor concentrates, FVIII levels in 37 bags of random cryoprecipitate were measured at 0, 2, 4 and 6 h after thawing, kept at room temperature with bacteriological culture studies performed on the sixth hour. The mean FVIII content at hour 0 was 108.10 U per bag. Type ORh+ blood had lower FVIII content (±78.91 U per bag) compared with blood types ARh+ (±121.64 U per bag) and BRh+ (±117.04 U per bag). The units stored <6 months had higher FVIII content (±117.74 U per bag) compared with those stored for over 6- but <12-months (±66.77 U per bag). The mean rate of decline of FVIII activity at 2, 4 and 6 h was statistically significant at 10.35% (P = 0.000), 21.49% (P = 0.000) and 29.41% (P = 0.000) from baseline, respectively, using the paired t-test. Similar finding was found across different blood types and storage duration. Only one of 37 bags grew Staphylococcus aureus on day 10 of incubation. [source] Valuing reductions in on-the-job illness: ,presenteeism' from managerial and economic perspectivesHEALTH ECONOMICS, Issue 4 2008Mark V. Pauly Abstract This paper reports on a study of manager perceptions of the cost to employers of on-the-job employee illness, sometimes termed ,presenteeism,' for various types of jobs. Using methods developed previously, the authors analyzed data from a survey of more than 800 US managers to determine the characteristics of various jobs and the relationship of those characteristics to the manager's view of the cost to the firm of absenteeism and presenteeism. Jobs with characteristics that suggest unusually high cost (relative to wages) were similar in terms of their ,absenteeism multipliers' and their ,presenteeism multipliers.' Jobs with high values of team production, high requirements for timely output, and high difficulties of substitution for absent or impaired workers had significantly higher indicators of cost for both absenteeism and presenteeism, although substitution was somewhat less important for presenteeism. Copyright © 2007 John Wiley & Sons, Ltd. [source] Liver transplantation for the sequelae of intra-operative bile duct injuryHPB, Issue 3 2002E De Santibañes Background Intra-operative bile duct injuries (IBDI) are potentially severe complications of the treatment of benign conditions, with unpredictable long-term results. Multiple procedures are frequently needed to correct these complications. In spite of the application of these procedures, patients with severe injuries can develop irreversible liver disease. Liver transplantation (LT) is currently the only treatment available for such patients, but little information has been published concerning the results of LT. Methods Eight patients with LT for end-stage liver disease for IBDI were studied retrospectively. They had failure of multiple previous treatments and experienced recurrent episodes of cholangitis, oesophageal variceal bleeding, severe pruritus, refractory ascites and spontaneous peritonitis. Results Mean recipient hepatectomy time was of 243 minutes (range 140,295 min), the complete procedure averages 545 minutes (260,720) and intraoperative red-blood-cells consumption was 6.5 units (1,7). One patient required reoperation due to perforation of a Roux-en-Y loop, and three developed minor complications (2 wound infections, 1 inguinal lymphocele). One patient died due to nosocomial pneumonia (mortality rate 12.5%). One patient required retransplantation due to delayed hepatic artery thrombosis. At follow-up 75% of patients are alive with normal graft function and an excellent quality of life. Conclusions LT represents a safe curative treatment for end-stage liver disease after IBDI, albeit a major undertaking in the context of a surgical complication in the treatment of benign disease. The complications of the surgical procedure and the long-standing immunosupression impart a high cost for resolutions of these sequelae but LT represents the only long-term effective treatment for these selected patients. [source] The role of algorithm and result comprehensibility of automated scheduling on complacencyHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 6 2008Julien Cegarra Several studies have stressed that even expert operators who are aware of a machine's limits could adopt its proposals without questioning them (i.e., the complacency phenomenon). In production scheduling for manufacturing, this is a significant problem, as it is often suggested that the machine be allowed to build the production schedule, confining the human role to that of rescheduling. This article evaluates the characteristics of scheduling algorithms on human rescheduling performance, the quality of which was related to complacency. It is suggested that scheduling algorithms be characterized as having result comprehensibility (the result respects the scheduler's expectations in terms of the discourse rules of the information display) or algorithm comprehensibility (the complexity of the algorithm hides some important constraints). The findings stress, on the one hand, that result comprehensibility is necessary to achieve good production performance and to limit complacency. On the other hand, algorithm comprehensibility leads to poor performance due to the very high cost of understanding the algorithm. © 2008 Wiley Periodicals, Inc. [source] A sequential equilibrium for the army's targeted selective reenlistment bonus programHUMAN RESOURCE MANAGEMENT, Issue 1 2007Scott E. Carrell Wecompute a sequential equilibrium for the U.S.Army'sTargeted Selective Reenlistment Bonus Program in whichtheArmy offers a bonus, soldiers with a low cost of serving in an undesirable location accept the bonus and are sent to an undesirable location, and soldiers with a high cost of serving in an undesirable location reenlist but decline the bonus.Wefind that this program benefits both theArmy and soldiers, increases retention, increases the number of soldierswho serve in an undesirable location, and better matches soldiers to assignments. We discuss implications of our model on human resource management practices for theArmy in its administration of the bonus program and its application to other large organizations that set wages through a rules-based mechanism. © 2007 Wiley Periodicals, Inc. [source] Combining the Filtered Evaluation Function With Coevolutionary Shared Niching in Genetic AlgorithmsINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 3 2001Keiji Suzuki In this paper, we propose the combination of filtered evaluation and coevolutionary shared niching (CSN) for extending the search ability of genetic algorithms (GA). The proposed scheme can overcome the problems of the filtering GA (FGA) and the CSN. The successful optimization ability of the FGA is supported by the filtered evaluation method that can modify the landscape for escaping local optima. However, the problem of the FGA is the relatively high cost to maintain the filter. The CSN can autonomously maintain the shared distance using the coevolution between two populations (called customers and businessmen). However, the escaping ability from local optima of the CSN is still insufficient. Therefore, the combination of the filtered evaluation and the CSN is proposed, to reduce the cost of the FGA filter. The effectiveness of the proposed scheme is confirmed through test problems. [source] Relationship between Carbon Isotope Discrimination, Mineral Content and Gas Exchange Parameters in Vegetative Organs of Wheat Grown under Three Different Water RegimesJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2010L. Zhu Abstract Carbon isotope discrimination (,) has been proposed as an indirect selection criterion for transpiration efficiency and grain yield in wheat. However, because of high cost for , analysis, attempts have been made to identify alternative screening criteria. Ash content (ma) has been proposed as an alternative criterion for , in wheat and barley. A pot experiment was conducted to analyse the relationship between ,, mineral content and gas exchange parameters in seedlings and leaves of bread wheat (Triticum aestivum L.). Plants of 10 genotypes were cultivated under three different water regimes corresponding to moderate (T3), intermediate (T2) and severe drought (T1) stress obtained by maintaining soil humidity at 75 %, 55 % and 45 % of the humidity at field capacity respectively. , and ma in seedlings and leaves showed significant differences among the three water treatments. Significant positive correlations were found between , and ma in seedlings and leaves at elongation and anthesis stages in severe drought stress (T1). , was negatively associated with potassium (K) content in intermediate drought stress (T2) and positively with magnesium (Mg) content in T2 and T3 (moderate drought stress) in flag leaf at anthesis. There were negative correlations between , and single-leaf intrinsic water-use efficiency (WT) in T2 and T3 at anthesis stage. Stronger positive associations were noted between , and stomatal conductance (gs) in T1 and T2 than in T3 at anthesis. These results suggested that , is a good trait as an indirect selection criterion for genotypic improvement in transpiration efficiency, while ma is a possible alternative criterion of , in wheat vegetative organs, especially in stressed environments. Significant association was found between , and K, Mg and Ca contents that would merit being better investigated. [source] Relationship between Carbon Isotope Discrimination and Mineral Content in Wheat Grown under Three Different Water RegimesJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2008L. Zhu Abstract Carbon isotope discrimination (,) has been proposed as an indirect selection criterion for transpiration efficiency and grain yield in wheat. However, because of the high cost for , analysis, attempts have been carried out to identify alternative screening criteria. Ash content (ma) has been proposed as an alternative criterion for , in wheat and barley. A pot experiment was conducted to analyse the relationship between , and ma in flag leaf and grain. Plants of 10 genotypes were cultivated under three different water regimes corresponding to moderate, intermediate and severe drought stress obtained by maintaining soil humidity at 75 %, 55 % and 45 % of the humidity at field capacity, respectively. , and ma in flag leaf and grain showed significant differences between the moderate, intermediate and severe drought stress levels. Significant correlations were found among genotypes for , and ma in flag leaf under severe drought stress, and for , and ma in grain under intermediate and moderate drought stress. In flag leaf at anthesis, , was negatively associated to K content and positively to Mg content. At maturity, , in grain was negatively correlated with Mg and Ca contents in flag leaf and grain, respectively. These results suggested that these traits may be potentially useful traits, which could be surrogates for ,. [source] Bulky Achiral Triarylphosphines Mimic BINAP in Ru(II)- Catalyzed Asymmetric Hydrogenation of KetonesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2005Qing Jing Abstract In the present work, we report on catalysis of the enantioselective hydrogenation of ketones with Ru(II) complexes composed of cheap achiral monodentate phosphine ligands in combination with an enantiopure 1,2-diamine, affording a variety of optically active secondary alcohols with high efficiency and enantioselectivity. The steric impact of achiral monophosphine ligands in Ru complexes was found to be a critical factor for the high enantioselectivity of the reaction. This finding throws some light on a long-standing challenge, the high cost of chiral bisphosphine ligands, associated with an industrial application of the asymmetric hydrogenation of ketones. [source] Negotiation of parental care when the stakes are high: experimental handicapping of one partner during incubation leads to short-term generosityJOURNAL OF ANIMAL ECOLOGY, Issue 1 2010Karen L. Wiebe Summary 1. Most game theoretical models of biparental care predict that a reduction in care by one partner should not be fully compensated by increased work of its mate but this may not be true for incubating birds because a reduction in care could cause the entire brood to fail. 2. I performed the first handicapping experiment of both males and females during incubation, by placing small lead weights on the tails of male and female northern flickers Colaptes auratus, a woodpecker in which males do most of the incubation. 3. Females responded to the acute stressor (handling and handicapping) by tending to abandon more readily than males and staying away from the nest longer in the first incubation bout. Among pairs that persisted, both males and females compensated fully for a handicapped partner, keeping the eggs covered nearly 100% of the time. 4. Partners did not retaliate by forcing their handicapped mate to sit on the eggs with a long incubation bout length subsequent to having a long bout length themselves. Instead, during the 24 h immediately after handicapping, males behaved generously by relieving handicapped females early. 5. Such generosity was probably not energetically sustainable as these male partners took on less incubation in the 72 h following handicapping compared to female partners of handicapped males. Males and females are probably generous in the short-term because of the high cost of nest failure during incubation but maintaining increased work loads in the longer term is probably limited by body condition and abandonment thresholds consistent with game theory models. [source] Small and large anemonefishes can coexist using the same patchy resources on a coral reef, before habitat destructionJOURNAL OF ANIMAL ECOLOGY, Issue 5 2002Akihisa Hattori Summary 1According to meta-population models, a superior competitor and a superior disperser can coexist in a patchy environment. The two anemonefishes, a large aggressive Amphiprion clarkii Bennett and a small less-aggressive A. perideraion Bleeker, use the same host anemone Heteractis crispa Ehrenberg on a coral reef, Okinawa, Japan, where most of the hosts disappeared after the coral bleaching in 1998. Their microhabitat (host) use and coexistence, and the quality and quantity of microhabitats were investigated in 1988, 1989, 1999 and 2000 on the coral reef. Their interspecific interaction was also examined. 2Before the habitat destruction, the two species coexisted. Although A. clarkii was behaviourally dominant over A. perideraion in a cohabiting group, A. perideraion was a superior competitor in terms of site displacement, because A. perideraion could displace a microhabitat. Adult A. clarkii emigrated from a cohabiting group probably due to the high cost of interactions with adult A. perideraion . Although it is easier to defend a small area for a larger species, sharing a host with adult A. perideraion may not pay for A. clarkii because A. clarkii needs a larger area. 3A. clarkii was not only a superior disperser, which was able to find a vacated host, but also a pioneer species that was able to use newly settled small hosts. Larval A. clarkii settled on such a small host because they were able to move to larger hosts for future reproduction, while A. perideraion did not settle on a small host because of low mobility after settlement. Microhabitat (host) with various sizes might have promoted their coexistence. 4After the habitat destruction, the superior competitor A. perideraion went extinct locally due probably to lack of small host utilization ability. The present study implies that the difference in body size between the two competitors plays an important role in their coexistence, because species with different body sizes can have different mobility and require different amounts of resources. [source] Methods of detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythensis in periodontal microbiology, with special emphasis on advanced molecular techniques: a reviewJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2004Mariano Sanz Abstract Background: Certain specific bacterial species from the subgingival biofilm have demonstrated aetiological relevance in the initiation and progression of periodontitis. Among all the bacteria studied, three have shown the highest association with destructive periodontal diseases: Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Tannerella forsythensis (Tf). Therefore, the relevance of having accurate microbiological diagnostic techniques for their identification and quantification is clearly justified. Aim: To evaluate critically all scientific information on the currently available microbial diagnostic techniques aimed for the identification and quantification of Aa, Pg and Tf. Summary: Bacterial culturing has been the reference diagnostic technique for many years and, in fact, most of our current knowledge on periodontal microbiology derives from cultural data. However, the advent of new microbial diagnostics, mostly based on immune and molecular technologies, has not only highlighted some of the shortcomings of cultural techniques but has also allowed their introduction as easy and available adjunct diagnostic tools to be used in clinical research and practice. These technologies, mostly polymerase chain reaction (PCR), represent a field of continuous development; however, we still lack the ideal diagnostic to study the subgingival microflora. Qualitative PCR is still hampered by the limited information provided. Quantitative PCR is still in development; however, the promising early results reported are still hampered by the high cost and the equipment necessary for the processing. Conclusion: Quantitative PCR technology may have a major role in the near future as an adjunctive diagnostic tool in both epidemiological and clinical studies in periodontology. However, culture techniques still hold some inherent capabilities, which makes this diagnostic tool the current reference standard in periodontal microbiology. [source] Basal replication of hepatitis C virus in nude mice harboring human tumorJOURNAL OF MEDICAL VIROLOGY, Issue 3 2002Patrick Labonté Abstract Hepatitis C virus (HCV) can infect and propagate in humans and chimpanzees. Whereas the chimpanzee has been used as an animal model for infection, ethical considerations, conservation, and the prohibitively high cost preclude progress for experimental research on the biology of the virus. The development of a small animal model for HCV infection is thus desirable to facilitate studies on the infectious cycle of the virus and for the evaluation of drugs for the treatment of HCV infections in humans. As an alternative to the chimpanzee model, we have established a model based on ex vivo infection of orthotopically-implanted human hepatocellular carcinoma cells (HCC) in athymic nude mice. The results show that up to 42 days post-infection, HCV RNA was present in the tumor cells as well as in the liver and serum of infected mice. Furthermore, a direct correlation between size of the tumor and the presence of HCV RNA in the liver was observed, which is concordant with the finding that HCV RNA was detectable only in mice harboring human tumor. Immunohistochemistry analysis of infected liver specimens showed cells expressing the HCV encoded NS5B protein. A few mice developed a humoral response against the nonstructural viral proteins, providing further evidence for expression of these proteins during viral infection. In summary, these results suggest that mice harboring orthotopic tumors support a basal level of HCV replication in vivo. J. Med. Virol. 66:312-319, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||