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Selected AbstractsNeurofuzzy Modeling of Context,Contingent Proximity RelationsGEOGRAPHICAL ANALYSIS, Issue 2 2007Xiaobai Yao The notion of proximity is one of the foundational elements in humans' understanding and reasoning of the geographical environments. The perception and cognition of distances plays a significant role in many daily human activities. Yet, few studies have thus far provided context,contingent translation mechanisms between linguistic proximity descriptors (e.g., "near,""far") and metric distance measures. One problem with previous fuzzy logic proximity modeling studies is that they presume the form of the fuzzy membership functions of proximity relations. Another problem is that previous studies have fundamental weaknesses in considering context factors in proximity models. We argue that statistical approaches are ill suited to proximity modeling because of the inherently fuzzy nature of the relations between linguistic and metric distance measures. In this study, we propose a neurofuzzy system approach to solve this problem. The approach allows for the dynamic construction of context,contingent proximity models based on sample data. An empirical case study with human subject survey data is carried out to test the validity of the approach and to compare it with the previous statistical approach. Interpretation and prediction accuracy of the empirical study are discussed. [source] Customary Law in Common Law SystemsIDS BULLETIN, Issue 1 2001Gordon R. Woodman Summaries How can the idea of the ,rule of law' be made a reality for ordinary people in African countries where customary law still underpins popular experience of ,law as practice'? It is argued that the idea of law itself should include all non-state ,normative orders' that are known, acceptable and pre-determined, as well as state law. What is called customary law is often closer to observed social norms (practised law) than the state law imported by colonialism, and indeed evolves in line with social and economic change, particularly in the field of land tenure. Any notion of the rule of law must support the institutions of customary law. One problem, however, is that in any country there are many different bodies of customary law particular to different localities, regions, cultures. This diversity must be both researched and recognised. [source] The development of effector and memory T cells in cutaneous leishmaniasis: the implications for vaccine developmentIMMUNOLOGICAL REVIEWS, Issue 1 2004Phillip Scott Summary:,Leishmania major infections induce the development of a CD4+ T-helper 1 (Th1) response that not only controls the primary infection but also results in life-long immunity to reinfection. How that immunity is maintained is unknown, although because of the existence of infection-induced immunity, there has been an assumption that the development of a vaccine against leishmaniasis would be relatively easy. This has turned out not to be the case. One problem has been the finding that a large part of the immunity induced by a primary infection depends upon the presence of persistent parasites. Nevertheless, there are ample situations where immunologic memory persists without the continued presence of antigen, providing the prospect that a non-live vaccine for leishmaniasis can be developed. To do so will require an understanding of the events involved in the development of an effective protective T-cell response and, more importantly, an understanding of how to maintain that response. Here, we review work from our laboratory, describing how Th1 cells develop in L. major -infected mice, the nature of the memory T cells that provide protection to reinfection, and how that information may be utilized in the development of vaccines. [source] What Is Ecological Validity?INFANCY, Issue 4 2001A Dimensional Analysis Ecological validity has typically been taken to refer to whether or not one can generalize from observed behavior in the laboratory to natural behavior in the world. Although common in current discussions of research, the idea of ecological validity has a long history in psychological thought. A brief historical examination of this idea reveals that concerns with ecological validity are evident in multiple dimensions of experimental work, including the nature of the experimental setting, the stimuli under investigation, and the observer's response employed as the measure. One problem with this multidimensionality, however, is that no explicit criteria have been offered for applying this concept to an evaluation of research. One consequence of this problem is that concerns with ecological validity can be raised in most experimental situations. This article includes a discussion of some demands of ecological validity and the nature of these different dimensions, as well as a critical evaluation of research on the development of mobility with respect to these constraints. [source] Targeted delivery of salicylic acid from acne treatment products into and through skin: role of solution and ingredient properties and relationships to irritationINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2004L. Rhein Salicylic acid (SA) is a beta-hydroxy acid and has multifunctional uses in the treatment of various diseases in skin such as acne, psoriasis, and photoaging. One problem often cited as associated with salicylic acid is that it can be quite irritating at pH 3,4, where it exhibits the highest activity in the treatment of skin diseases. We have identified strategies to control the irritation potential of salicylic acid formulations and have focused on hydroalcoholic solutions used in acne wipes. One strategy is to control the penetration of SA into the skin. Penetration of the drug into various layers of skin, i.e. epidermis, dermis, and receptor fluid, was measured using a modified Franz in vitro diffusion method after various exposure times up to 24 h. A polyurethane polymer (polyolprepolymer-15) was found to be an effective agent in controlling delivery of SA. In a dose-dependent fashion it targeted delivery of more SA to the epidermis as compared to penetration through the skin into the receptor fluid. It also reduced the rapid rate of permeation of a large dose of SA through the skin in the first few hours of exposure. A second strategy that proved successful was incorporation of known mild nonionic surfactants like isoceteth-20. These surfactants cleanse the skin, yet due to their inherent mildness (because of their reduced critical micelle concentration and monomer concentration), keep the barrier intact. Also, they reduce the rate of salicylic acid penetration, presumably through micellar entrapment (either in solution or on the skin surface after the alcohol evaporates). Cumulative irritation studies showed that targeting delivery of SA to the epidermis and reducing the rapid early rate of penetration of large amounts of drug through the skin resulted in a reduced irritation potential. In vivo irritation studies also showed that the surfactant system is the most important factor controlling irritancy. SA delivery is secondary, as formulations with less SA content reduced the rate of delivery to the receptor and yet were some of the most irritating formulations tested, presumably due to the action of the specific anionic surfactant on the barrier. Alcohol content also did not appreciably affect irritation and SA delivery; formulations with considerably low alcohol content but containing anionic versus nonionic surfactant systems exhibited considerably higher irritancy. Thus the surfactant type was again the predominant factor in those studies, although arguably alcohol plays some role (solubilization of SA). Results showed that both polymers and mild surfactants work in concert to provide the optimal formulation benefits of targeted delivery and reduced irritation. Synergistic relationships among hydroalcoholic formulation components will be discussed along with the mechanisms likely involved in controlling delivery of SA to skin. [source] Fuzzy set methods for uncertainty management in intelligence analysisINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2006Ronald R. Yager Considerable concern has arisen regarding the quality of intelligence analysis. This has been, in large part, motivated by the task of determining whether Iraq had weapons of mass destruction. One problem that made this analysis difficult was the uncertainty in much of the information available to the intelligence analysts. In this work, we introduce some tools that can be of use to intelligence analysts for representing and processing uncertain information. We make considerable use of technologies based on fuzzy sets and related disciplines such as approximate reasoning. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 523,544, 2006. [source] CREATING VALUE IN THE OIL INDUSTRYJOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2004Nick Antill In contrast with current thinking that conglomerates are inefficient, this article begins by presenting arguments in favor of the size and structure of the large integrated oil companies, also known as "the supermajors." Among the advantages are tax efficiency, information flow, political and technological know-how, broad supplier and customer relationships, scale economies, cross-business economies of scope, brand power, and the ability to coordinate strategic initiatives across businesses. These advantages all translate into a lower cost of capital. One problem, however, is that this lower cost of capital does not seem to be reflected in the target returns on capital currently set by the supermajors. Observing that the financial goal of a corporation is to maximize not its return on capital but rather the net present value of expected future cash flows and earnings, the authors argue that the majors need to make two major changes to current practice. First, their investment hurdle rates should be reduced from their current level of 14,15% to the weighted average cost of capital, which is estimated to run about 8,9%. Second, the actual returns on capital reported in published accounts are largely meaningless; and when evaluating new investments and existing operations alike, the companies must find an annual performance measure that better reflects the economic realities of the business. This paper recommends use of a performance measurement framework based on economic profit that should serve two critical purposes: it will encourage managers to undertake all value-increasing projects (not just those that will maintain or increase reported return on capital), and it will help the companies communicate their strategy and results to the investment community. [source] Satellite species in lampreys: a worldwide trend for ecological speciation in sympatry?JOURNAL OF FISH BIOLOGY, Issue 2 2003V. Salewski Amongst several theories of speciation, sympatric speciation has been the most controversial but it is now widely accepted that populations can become reproductively isolated without being separated geographically. One problem with the acceptance of the theory of sympatric speciation, however, has been the lack of supporting empirical data and it is still believed that geographical isolation is responsible for the majority of speciation events. Here the example of species pairs in lampreys suggests that sympatric speciation in a whole taxonomic group could occur throughout its worldwide range. Lampreys occur in two ecologically distinct forms: parasitic mostly anadromous species that forage on tissue and body fluids of host fishes, and non-parasitic forms that, apart from a short adult life when they cease feeding, spend their entire life as filter feeders in the substratum of stream beds. Both forms occur in sympatric species pairs throughout the range of lampreys that occur in Eurasia, North America and Australia and it is widely acknowledged that non-parasitic forms derive from parasitic forms. The larvae of both forms can be distinguished by their potential fecundity and therefore, it is argued that the mode of life is not a consequence of different ecological conditions. Furthermore, as lampreys prefer to choose mates of similar sizes and fertilization success decreases with increasing difference in body size, there is a strong disruptive selection between the two forms and they are therefore reproductively isolated. Besides theoretical aspects, the similarity of the species pairs, together with their occurrence in sympatry, the occurrence of forms with intermediate characteristics, and examples where speciation might be in progress, hints at the possibility that speciation also occurred in sympatry. The difference between lampreys and other examples of sympatric speciation is that there seems to be a trend towards sympatric speciation events throughout the worldwide range of lampreys which is neither restricted to relatively small localities nor caused by human disturbance. Species pairs in lampreys therefore offer a unique possibility of studying the process of sympatric speciation on a large scale. [source] GEOLOGICAL INTERPRETATION OF WELL TEST ANALYSIS: A CASE STUDY FROM A FLUVIAL RESERVOIR IN THE GULF OF THAILANDJOURNAL OF PETROLEUM GEOLOGY, Issue 1 2003S. Y. Zheng One problem with the inversion of transient well test data is that it can yield a non-unique solution. The uncertainty resulting from this type of approach can only be resolved by considering information from another source such as geology. Geological information will help to define the interpretation model which will ensure the correct analysis of the well test data. The results of well test analyses are of little value to reservoir characterisation and modelling unless they can be explained from a geological point of view. This last step is what we refer to here as geological interpretation. Other sources of information which can help with well test analyses come from seismic surveys and petrophysics. Modern well test interpretation therefore consists of two major steps: analysis of the well test data; and interpretation of the results. In detail, this should include the following: 1definition of an interpretation model , this requires the integration of geological, seismic and petrophysical data with transient pressure data 2analysis of the well test data based on the interpretation model defined 3geological interpretation of the results, which is necessary in order to explain or give meaning to the results. In this paper, we present a case study from a fluvial gas reservoir in the Gulf of Thailand which demonstrates these procedures. In the context of a defined geological environment, a transient pressure test has been fully analysed. Newly-developed software based on the finite element method has been used to forward model the test scenarios. This allowed the results of seismic and petrophysical analyses to be integrated into the well test model. This case study illustrates the integrated use of geological, petrophysical, well test and seismic attribute data in defining a reservoir model which respects both the reservoir geometry at some distance from the well location and also the reservoir's heterogeneity. We focus on a particular well in the Pattani Basin at which conventional well test analyses have been conducted. By considering the results of these analyses, forward modelling was carried out in which the drainage area was "cut" out of the structural map defined by seismic interpretation; also, the formation's internal heterogeneity was modelled according to well logs and petrophysical analyses. Finally, analytical and simulation results were compared with the transient pressure data. We conclude that the integration of geological, seismic, petrophysical and well test data greatly reduced uncertainties in well test interpretation. The consistency of the results and the fact that they satisfied all the relevant disciplines meant that much more confidence could be given to their interpretation. [source] Corrosion behaviour of tool steels in tannic acidsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 3 2009H. Winkelmann Abstract It is well known that cutting knifes in the wood industry often suffer from corrosion. Investigations showed that the corrosiveness of different wood types is responsible for a major part of the damage, and that different woods have a different corrosive impact. It is revealed that tannin, a water-soluble acid, which can be found in all woods in different concentrations, is the most aggressive acid contained in the wood, and so it is responsible for the main part of the corrosive attack. In view of the above, the ability of different cold-work steels to resist corrosion caused by tannic acid has been investigated. Often corrosion is measured by the mass loss of the sample divided by the surface of the sample under certain conditions during a fixed period of time. One problem with this method is that there is also a weight gain caused by oxidation or by other side reactions at the samples surface. So in some cases the weight of the sample even increases during the testing time, which makes the quantification of the corrosion impossible with this method. Due to the reasons already mentioned, another method was used to quantify the test results. This method is based on inductive coupled plasma,optical emission spectral analyses (ICP-OES), where the released Fe is quantified. The results of the corrosion resistant tests get correlated to the microstructure and the elemental composition of the analysed cold-work steels. The present investigations improve the understanding of important material parameters to enhance the corrosion resistance against tannin. It is revealed that the higher the primary carbide concentration is the more Cr or other passivating elements are necessary in the matrix to show a good protection against corrosion by tannin. Three materials with different elemental compositions have been investigated, and for one of those materials the influence of different heat treatments was also analysed. The investigations could show that annealing parameters and freeze-cycle processing (FCP) have less impact on the corrosion resistance to tannin than elemental composition and austenitising temperature. [source] Finite energy solutions of self-adjoint elliptic mixed boundary value problemsMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 12 2010Giles Auchmuty Abstract This paper describes existence, uniqueness and special eigenfunction representations of H1 -solutions of second order, self-adjoint, elliptic equations with both interior and boundary source terms. The equations are posed on bounded regions with Dirichlet conditions on part of the boundary and Neumann conditions on the complement. The system is decomposed into separate problems defined on orthogonal subspaces of H1(,). One problem involves the equation with the interior source term and the Neumann data. The other problem just involves the homogeneous equation with Dirichlet data. Spectral representations of the solution operators for each of these problems are found. The solutions are described using bases that are, respectively, eigenfunctions of the differential operator with mixed null boundary conditions, and certain mixed Steklov eigenfunctions. These series converge strongly in H1(,). Necessary and sufficient conditions for the Dirichlet part of the boundary data to have a finite energy extension are described. The solutions for a problem that models a cylindrical capacitor is found explicitly. Copyright © 2009 John Wiley & Sons, Ltd. [source] Reinventing Reforms: How to Improve Program Management Using Performance Measures.PUBLIC BUDGETING AND FINANCE, Issue 3 2010Really This paper looks at the design and use of incentivized performance measures to motivate managerial efficiency and promote greater program effectiveness. It starts off by looking at recent reforms like the Government Performance and Results Act to understand why they were largely unsuccessful in altering the decision-making process of government agencies. One problem was that performance measures have been both numerous and complicated, thereby making their role in management and oversight difficult. Equally important, no external incentives were attached to program accomplishments. The paper then examines what elements would be needed to build a management system that encourages both more efficient and more effective agency behavior. The goal of performance budgeting is to develop performance measures that display the progress of a program toward its stated objectives. Assessments based on these measures may then call for rewards or punishments. As such, it also may encourage program managers toward improved performance. The paper examines the pitfalls and complexities dealt with by Congress and Office of Management and Budget in the process. For example, a performance system must distinguish between funding program needs, as warranted by sectoral indicators, and management concerns. It must also unambiguously tie incentives to performance measures to motivate agencies, while building in commitment devices for the principals. Incentivized performance measures may not be appropriate in all conditions, but may be helpful for motivating managers and improving program performance in particular circumstances. [source] Use of flubendazole as a therapeutic agent against rotifers (Brachionus plicatilis) in intensive cultures of the harpacticoid copepod Tisbe holothuriaeAQUACULTURE RESEARCH, Issue 7 2010Svend J Steenfeldt Abstract Copepods are well known to be the optimal live feed for most species of marine fish larvae. Still copepods are rarely used in marine hatcheries worldwide. Lack of efficient production techniques are among the reasons for this. Consequently, Artemia and rotifers are utilized in commercial settings. One problem in intensive production of copepods is contamination with rotifers. Rotifers have higher growth rates than copepods and consequently will compete out the copepods when accidentally introduced to the copepod production systems. Once contamination has occurred, the only cure has been to shut down production and subsequently use a therapeutic agent to eliminate all zooplankton in the system before restart with a stock culture free of rotifers. We tested flubendazole as a mean of controlling rotifers (Brachionus plicatilis) in intensive laboratory cultures of the harpacticoid copepod (Tisbe holothuria). Flubendazole was lethal to rotifers in concentrations as low as 0.05 mg L,1. There was no significant effect on the concentration of copepods, even at the highest concentration tested, i.e. 5.0 mg L,1 flubendazole. We conclude that flubendazole is an effective drug for control of B. plicatilis in T. holothuriae batch cultures. [source] The grassland farming system and sustainable agricultural development in ChinaGRASSLAND SCIENCE, Issue 1 2005Zhibiao Nan Abstract Grassland is the largest terrestrial ecosystem in China, at about 39 280 × 104 ha and covers 41% of the total land area. Grasslands not only provide forage to feed livestock, but also play a critical role in alleviating many of the most challenging environmental and ecological problems that humankind is facing. About 90% of the total usable grassland in China has been degraded to various extents and this is the number one problem facing agricultural production, rural development and environmental improvement. Research on grassland degradation has been carried out since the early 1950s. Enormous achievements have been made and theory and a technical system for pastoral agriculture have been developed. This pastoral agriculture system is a well-organized modern farming system including four production levels, that is, preplant, plant, animal and postbiotic levels, and is linked by three interfaces, including vegetation-site, grassland-animal and production-management. The system capacity and productivity could be improved by system coupling. Since it emerged, this pastoral agriculture system has been established in various ecological regions in China and significant improvements in agricultural sustainability, farmer's income and environmental stability have been obtained. In the future, it will play a more critical role in developing sustainable agriculture in China. [source] The historical development of cryogenically cooled monochromators for third-generation synchrotron radiation sourcesJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2000Donald H. Bilderback In the period of the late-1980s, before the construction of multi-GeV third-generation storage rings with their intense insertion-device sources, the perceived number one problem for X-ray instrumentation was proper cooling of the first optical element in the beamline. This article, first given as an acceptance speech for the Compton Award ceremony at the Advanced Photon Source, presents a somewhat historical and anecdotal overview of how cryogenically cooled monochromator optics have been developed to provide a monochromator cooling solution adequate for today's power levels. A series of workshops and international collaborations were the key components for the progress and final success of this development. [source] Body image and sexual problems in young women with breast cancerPSYCHO-ONCOLOGY, Issue 7 2006Pat Fobair Abstract Purpose: The purpose of this study was to determine the frequency of body image and sexual problems in the first months after treatment among women diagnosed with breast cancer at age 50 or younger. Background: Breast cancer treatment may have severe effects on the bodies of younger women. Surgical treatment may be disfiguring, chemotherapy may cause abrupt menopause, and hormone replacement is not recommended. Methods: A multi-ethnic population-based sample of 549 women aged 22,50 who were married or in a stable unmarried relationship were interviewed within seven months of diagnosis with in situ, local, or regional breast cancer. Results: Body image and sexual problems were experienced by a substantial proportion of women in the early months after diagnosis. Half of the 546 women experienced two or more body image problems some of the time (33%), or at least one problem much of the time (17%). Among sexually active women, greater body image problems were associated with mastectomy and possible reconstruction, hair loss from chemotherapy, concern with weight gain or loss, poorer mental health, lower self-esteem, and partner's difficulty understanding one's feelings. Among the 360 sexually active women, half (52%) reported having a little problem in two or more areas of sexual functioning (24%), or a definite or serious problem in at least one area (28%). Greater sexual problems were associated with vaginal dryness, poorer mental health, being married, partner's difficulty understanding one's feelings, and more body image problems, and there were significant ethnic differences in reported severity. Conclusions: Difficulties related to sexuality and sexual functioning were common and occurred soon after surgical and adjuvant treatment. Addressing these problems is essential to improve the quality of life of young women with breast cancer. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||