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Selected AbstractsEvaluation of the PESERA model in two contrasting environmentsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2009F. Licciardello Abstract The performance of the Pan-European Soil Erosion Risk Assessment (PESERA) model was evaluated by comparison with existing soil erosion data collected in plots under different land uses and climate conditions in Europe. In order to identify the most important sources of error, the PESERA model was evaluated by comparing model output with measured values as well as by assessing the effect of the various model components on prediction accuracy through a multistep approach. First, the performance of the hydrological and erosion components of PESERA was evaluated separately by comparing both runoff and soil loss predictions with measured values. In order to assess the performance of the vegetation growth component of PESERA, the predictions of the model based on observed values of vegetation ground cover were also compared with predictions based on the simulated vegetation cover values. Finally, in order to evaluate the sediment transport model, predicted monthly erosion rates were also calculated using observed values of runoff and vegetation cover instead of simulated values. Moreover, in order to investigate the capability of PESERA to reproduce seasonal trends, the observed and simulated monthly runoff and erosion values were aggregated at different temporal scale and we investigated at what extend the model prediction error could be reduced by output aggregation. PESERA showed promise to predict annual average spatial variability quite well. In its present form, short-term temporal variations are not well captured probably due to various reasons. The multistep approach showed that this is not only due to unrealistic simulation of cover and runoff, being erosion prediction also an important source of error. Although variability between the investigated land uses and climate conditions is well captured, absolute rates are strongly underestimated. A calibration procedure, focused on a soil erodibility factor, is proposed to reduce the significant underestimation of soil erosion rates. Copyright © 2009 John Wiley & Sons, Ltd. [source] Genetic structure of Euphrasia stricta on the Baltic island of Gotland, SwedenECOGRAPHY, Issue 4 2005Anna-Karin Kolseth Genetic differentiation between and within five varieties of Euphrasia stricta (var. brevipila, var. gotlandica, var. stricta, var. suecica and var. tenuis) on Gotland was investigated, using amplified fragment length polymorphism, AFLP. The varieties are described in the literature by morphology and association to habitat type. We wanted to investigate whether the varieties are locally adapted populations to the typical habitat type for each variety or if they are preadapted to certain habitat types and have colonized Gotland in their present form. A constrained principal coordinate analysis revealed three genetically differentiated subunits within the species. The two early-flowering varieties suecica and tenuis each formed a distinct group, while the three late-flowering varieties brevipila, gotlandica and stricta together formed the third group. A phylogenetic tree confirms the partitioning into three groups. Within the group containing the late-flowering varieties there are populations that pair as each other's closest relatives, but belong to different varieties. These pairs are also geographically adjacent. The phylogenetic tree had a "star-like" appearance indicating a stronger divergence between populations than between varieties. The same pattern was seen in the partitioning of genetic diversity, with a lower amount of genetic variation occurring between varieties, FST=0.14, than between populations within the varieties, FST ranging from 0.26 to 0.60. In Euphrasia stricta the varieties suecica and tenuis and the group containing the varieties stricta/gotlandica/brevipila are likely to have a phylogeographical history outside Gotland, or an ancient and concealed local origin on the island. Within the group stricta/gotlandica/brevipila local evolutionary events seem to determine the variety identity, probably through local adaptation. [source] HOW TO CLEAR UP THE PENSIONS MESSECONOMIC AFFAIRS, Issue 3 2003David Simpson All three pillars of the British pensions system are crumbling. The basic state pension is unsustainable in its present form. Defined benefit occupational pension schemes are fast disappearing, and with them the retirement hopes of millions of workers. A further 3 million low-income earners are not saving enough for their retirement. And uncertainty about pensions choices is widespread. In each case the primary cause of the problem is governmental or regulatory failure. The paper makes eight general and four specific proposals for restoring the system. [source] The psychological contract: A critical reviewINTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 2 2006Niall Cullinane Literature on the psychological contract has blossomed progressively over the last ten years to the extent that it is now firmly located within the lexicon of the Human Resource Management (HRM) discipline. Yet as this review indicates, the theoretical assumptions that seem to pervade the psychological contract literature are not without major deficiencies, which in turn pose serious questions around the continued sustainability of the construct as currently constituted. This paper addresses some of the central problems presently confronting the theoretical side of the psychological contract literature. In seeking to advance knowledge and understanding, this review calls for an alternative approach to studying the psychological contract on the basis of a more critical and discursive literature analysis. From this, the authors unpick the construct of the psychological contract as portrayed in much of the extant literature and argue that, in its present form, it symbolizes an ideologically biased formula designed for a particular managerialist interpretation of contemporary work and employment. [source] A validation of the Dyslexia Adult Screening Test (DAST) in a post-secondary populationJOURNAL OF RESEARCH IN READING, Issue 4 2005Allyson G. Harrison In Ontario, Canada, there is a demand for psychometrically robust screening tools capable of efficiently identifying students with specific learning disabilities (SLD), such as dyslexia. The present study investigated the ability of the Dyslexia Adult Screening Test (DAST) to discriminate between 117 post-secondary students with carefully diagnosed SLDs and 121 comparison students. Results indicated that the DAST correctly identified only 74% of the students with SLDs as ,highly at risk' for dyslexia. Although employing the cutoff for ,mildly at risk' correctly identified 85% of the students with SLDs, this also increased the percentage of students with no major history of learning problems identified as ,at risk' for dyslexia from 16% to 26%. These findings suggest that the DAST in its present form is limited in its ability to screen for SLDs. Implications for future research are discussed. [source] Surface texture characterization of injection-molded pigmented plasticsPOLYMER ENGINEERING & SCIENCE, Issue 9 2004Ingrid Ariño An appropriate description of the surface textures deliberately created on injection-molded plastic parts of interior car components is presented. A spatial wavelength-dependent analysis is used as an interesting alternative to the traditional roughness parameters. Auto-correlation functions and power spectral densities are examples of such spectral functions that include parameters both in amplitude and profile directions. Even fractal concepts can be useful descriptors. As an illustration, it is also shown how the effects on the surface topography of the plastic part of after-etching the mold can be assessed by suitable descriptors. An experimental evaluation of injection-molded plaques containing three different surface patterns was carried out using an optical profilometer, supplemented by contact stylus measurements. The ability to assess the topography of these plaques by means of a new fast photometric stereo-technique, denoted OptiTopo, was also evaluated. In its present form, however, this technique does not provide a detailed description of the topography of a pigmented plastic. Reasons for this and possible improvements are discussed. Polym. Eng. Sci. 44:1615,1626, 2004. © 2004 Society of Plastics Engineers. [source] Private tax collection,remnant of the past or a way forward?PUBLIC ADMINISTRATION & DEVELOPMENT, Issue 4 2006Evidence from rural Uganda Abstract This article examines the growing role and impacts of private tax collection under fiscal decentralisation in Uganda. Based on evidence from six rural councils, three aspects of privatised tax collection are examined: (i) the impact on the nature of fiscal corruption; (ii) the problem of overzealous collection; and (iii) the challenge of assessing revenue potentials. While possibly meeting short-term demands for local revenue growth and stability, the present form of private tax collection appears to transform the nature of fiscal corruption by reducing corruption at collection point and transferring the problem into the district administration. Moreover, while the charge of overzealousness permeates historical and theoretical work on privatised tax collection, the Ugandan experience casts doubt on its general validity. Instead, perverse distributional effects are the most likely cause of deteriorating state-citizen relations in rural Uganda. Finally, the article considers the merit of the prediction of private collection as a preferred contractual choice for certain indirect taxes, suggesting that problems of asymmetric information in assessing the revenue yields of most rural markets are exaggerated. Copyright © 2006 John Wiley & Sons, Ltd. [source] Recent Developments in India's Plant Variety Protection, Seed Regulation and Linkages with UPOV's Proposed MembershipTHE JOURNAL OF WORLD INTELLECTUAL PROPERTY, Issue 3 2009Prabhash Ranjan The Agreement on Trade-Related Aspects of Intellectual Property Rights of the World Trade Organization imposes an obligation on all member countries to protect plant varieties either by patents or by a sui generis regime or by a combination of both. India explored the sui generis option to provide protection to plant varieties. This legal regime recognizes the rights of commercial breeders and also grants a positive right to farmers and goes beyond the widely recognized international sui generis regime represented by the International Union for the Protection of Plant Varieties (UPOV). Notwithstanding this, India has made an application to join UPOV. However, with the present plant variety law, India's membership application to join UPOV may not be successful. The recent development of bringing the Seeds Bill, which dilutes farmers' rights provisions in the plant variety law, is important in this regard. The article argues that if the Seeds Bill is passed in its present form, it will dilute the beneficial provisions of the plant variety law and pave the way for India to join UPOV. [source] The Future of a Discipline: Considering the ontological/methodological future of the anthropology of consciousness, Part I,ANTHROPOLOGY OF CONSCIOUSNESS, Issue 1 2010Toward a New Kind of Science, its Methods of Inquiry ABSTRACT Calling for an expanded framework of EuroAmerican science's methodology whose perspective acknowledges both quantitative/etic and qualitative/emic orientations is the broad focus of this article. More specifically this article argues that our understanding of shamanic and/or other related states of consciousness has been greatly enhanced through ethnographic methods, yet in their present form these methods fail to provide the means to fully comprehend these states. They fail, or are limited, because this approach is only a "cognitive interpretation" or "metanarrative" of the actual experience and not the experience itself. Consequently this perspective is also limited because the researcher continues to assess his or her data through the lens of their symbolic constructs, thereby preventing them from truly experiencing shamanic and psi/spirit approaches to knowing since the data collection process does not "in and of itself" affect the observer. We, therefore, need expanded ethnographic methods that include within their approaches an understanding of methods and techniques to experientially encounter these states of consciousness,and become transformed by them. Our becoming transformed and then recollecting our ethnoautobiographical experiences is the means toward a new kind of science and its methods of inquiry that this article seeks to encourage. [source] Effect of RGD peptide coating of titanium implants on periimplant bone formation in the alveolar crestCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2002An experimental pilot study in dogs Abstract: The aim of the present study was to analyse the effect of organic coating of titanium implants on periimplant bone formation and bone/implant contact. Three types of implants were used: (i) Ti6Al4V implants with polished surface (control 1) (ii) Ti6Al4V implants with collagen coating (control 2) (iii) Ti6Al4V implants with collagen coating and covalently bound RGD peptides. All implants had square cross-sections with an oblique diameter of 4.6 mm and were inserted press fit into trephine burr holes of 4.6 mm in the mandibles of 10 beagle dogs. The implants of five animals each were evaluated after a healing period of 1 month and 3 months, during which sequential fluorochrome labelling of bone formation was performed. Bone formation was evaluated by morphometric measurement of the newly formed bone around the implant and the percentage of implant bone contact. After 1 month there was only little bone/implant contact, varying between 2.6 and 6.7% in the cortical bone and 4.4 and 5.7% in the cancellous bone, with no significant differences between the three types of implants. After 3 months, implants with polished surfaces exhibited 26.5 and 31.2% contact in the cortical and cancellous bone, respectively, while collagen-coated implants had 19.5 and 28.4% bone contact in these areas. Implants with RGD coating showed the highest values with 42.1% and 49.7%, respectively. Differences between the surface types as such were not significant, but the increase in bone/implant contact from 1 to 3 months postoperatively was significant only in the group of RGD-coated implants (P = 0.008 and P = 0.000). The results of this pilot study thus provide only weak evidence that coating of titanium implants with RGD peptides in the present form and dosage may increase periimplant bone formation in the alveolar process. The results therefore require further verification in a modified experimental setting. Résumé Le but de l'étude présente a été d'évaluer l'effet d'un recouvrement organique des implants en titane sur la formation osseuse paro?mplantaire et le contact os/implant. Trois types d'implants ont été utilisés: 1) implants Ti6AI4V avec surface polie (contrôle 1), 2) implants Ti6AI4V avec recouvrement de collagène (contrôle 2), 3) implants Ti6aI4V avec recouvrement de collagène et des peptides RGD accrochés de manière covalente. Tous les implants avaient une section carrée avec un diamètre oblique de 4.6 mm et étaient insérés dans des trous percés à l'aide de trépans de 4.6 mm dans la mandibule de dix chiens beagle. Les implants de cinq animaux ont étéévalués après une période de guérison d'un mois et de trois mois durant laquelle un marquage fluochrome séquentiel de la néoformation osseuse a été effectué. La formation osseuse a étéévaluée par mesure morphométrique de l'os néoformé autour de l'implant et par pourcentage de contact os/implant. Après un mois, il n'y avait que peu de contact os/implant, variant entre 2.6 et 6.7% dans l'os cortical et 4.4 et 5.7% dans l'os spongieux, sans aucune différence significative entre les trois types d'implants. Après trois mois, les implants avec les surfaces polies montraient respectivement 26.5 et 31.2% d'os cortical et spongieux, tandis que les implants recouverts de collagène avaient 19.5 et 28.4% de contact osseux dans ces zones. Les implants avec le recouvrement RGD avaient les valeurs les plus importantes avec respectivement 42.1% et 49.7%. Les différences entre les types de surface n'étaient pas significatives mais l'augmentation du contact os/implant de 1 à 3 mois après l'opération n'était significative que dans le groupe RGD (P=0.008 et P=0.0000). Les résultats de cette ewtude pilote n'ont donc mis en évidence qu'une maigre preuve que les recouvrements des implants en titane par les petpides RGD sous la forme présente et le dosage présent, pouvaient augmenter la formation osseuse paro?mplantaire dans le processus alvéolaire. Ces résultats requièrent donc davantage de vérifications dans un système expérimental modifié. Zusammenfassung Es war das Ziel dieser Untersuchung, den Einfluss einer organischen Beschichtung von Titanimplantaten auf die periimplantäre Knochenformation und auf den KnochenImplantatkontakt zu analysieren. Drei Typen von Implantaten wurden verwendet: i) Ti6AI4V Implantate mit polierter Oberfläche (Kontrolle 1), ii) Ti6AI4V Implantate mit Kollagenbeschichtung (Kontrolle 2), iii) Ti6AI4V Implantate mit Kollagenbeschichtung und kovalent gebundenen RGD-Peptiden. Alle Implantate hatten einen quadratischen Querschnitt mit einem Querdurchmesser von 4.6 mm. Sie wurden in die Unterkiefer von zehn Beaglehunden in zylindrische Bohrungen mit einem Durchmesser von 4.6 mm mit Pressitz eingesetzt. Die Implantate von je funf Tieren wurden nach einer Helungszeit von einem bzw. drei Monaten ausgewertet. Während der gesamten Zeit wurden sequentielle Fluorochrommarkierungen der Knochenbildung durchgeführt. Die Knochenbildung wurde durch morphometrische Messungen des neugebildeten Knochens um die Implantate und durch Messungen der prozentualen Anteile des Knochen-/Implantatkontakts ausgewertet. Nach 1 Monat war nur wenig Knochen-/Implantatkontakt vorhanden. Er variierte zwischen 2.6 und 6.7% im kortikalen Knochen und zwischen 4.4 und 5.7% im spongiösen Knochen. Zwischen den drei Implantattypen bestanden keine signifikanten Unterschiede. Nach drei Monaten zeigten die Implantate mit polierten Oberflächen 26.5% Knochenkontakt im kortikalen bzw. 31.2% im spongiösen Knochen, während die kollagenbeschichteten Implantate 19.5% und 28.4% Knochenkontakt in diesen Regionen zeigten. Implantate mit RGD-Beschichtung zeigten mit 42.1% bzw. 49.7% die höchsten Werte. Zwischen den Oberflächentypen bestanden keine signifikanten Unterschiede. Nur in der Gruppe mit RGD-beschichteten Implantaten nahm der Knochen-/Implantatkontakt zwischen 1 bis 3 Monaten nach Chirurgie signifikant zu (P=0.008 und P=0.000). Die Resultate dieser zeigen nur mit schwacher Evidenz, dass die Beschichtung von Titanimplantaten mit RGD-Peptiden in der vorliegenden Form und Dosierung die periimplantäre Knochenformation im Alveolarkamm erhöht. Die Resultate müssen daher in einem modifizerten experimentellen Aufbau verifiziert werden. Resumen La intención del presente estudio fue analizar el efecto de la cobertura orgánica de implantes de titanio en la formación de hueso y contacto hueso/implante. Se usaron tres tipos de implantes: i) implantes de Ti6AI4V con superficie pulida (control 1), ii) implantes Ti6AI4V con cubierta de colágeno (control 2), iii) implantes de Ti6AI4V con cubierta de colágeno y péptidos RGD con unión convalente. Todos los implantes tenían secciones cuadradas con un diámetro oblicuo de 4.6 mm y se insertaron a presión en orificios trepanados de 4.6 mm en las mandíbulas de 10 perros beagle. Se evaluaron los implantes de 5 animales tras un periodo de cicatrización de un mes y tres meses los otros cinco, durante este tiempo se llevó a cabo marcado secuencial con fluorocromo de la formación de hueso. La formación de hueso se evaluó mediante mediciones morfométricas del hueso neoformado alrededor del implante y el porcentaje de contacto hueso implante. Tras 1 mes existió muy poco contacto hueso/implante variando entre 2.6 y 6.7% en el hueso cortical y 4.4 y 5.7% en el hueso esponjoso sin diferencias significativas entre los tres tipos de implantes. Tras tres meses, los implantes con superficies pulidas exhibieron un 26.5 y 31.2% en el hueso cortical y esponjoso, respectivamente, mientras que los implantes con cubiertas de colágeno tuvieron un 19.5 y un 28.4% de contacto óseo en estas áreas. Los implantes con cubiertas de RGD mostraron los valores más altos con un 42.1 y un 49.7% respectivamente. Las diferencias ente tipos de superficie como tales no fueron significativas pero el incremento de contacto hueso/implante de 1 a 3 meses tras la operación fue significativo solo en el grupo de implantes con cubierta RGD (P=0.008 y P=0.000). Los resultados de este estudio piloto aunque han mostrado solo una débil evidencia, que la cobertura de implantes de titanio con péptidos RGD en la forma y dosis presente pueden incrementar la formación de hueso periimplantario en el proceso alveolar. Los resultados, por lo tanto, requieren una posterior verificación en una situación experimental modificada. [source] Intelligent interaction design: the role of human-computer interaction research in the design of intelligent systemsEXPERT SYSTEMS, Issue 1 2001Ann BlandfordArticle first published online: 16 DEC 200 As more intelligent systems are introduced into the marketplace, it is becoming increasingly urgent to consider usability for such systems. Historically, the two fields of artificial intelligence (AI) and human- computer interaction (HCI) have had little in common. In this paper, we consider how established HCI techniques can usefully be applied to the design and evaluation of intelligent systems, and where there is an urgent need for new approaches. Some techniques - notably those for requirements acquisition and empirical evaluation - can usefully be adopted, and indeed are, within many projects. However, many of the tools and techniques developed within HCI to support design and theory-based evaluation cannot be applied in their present forms to intelligent systems because they are based on inappropriate assumptions; there is consequently a need for new approaches. Conversely, there are approaches that have been developed within AI - e.g. in research on dialogue and on ontologies - that could usefully be adapted and encapsulated to respond to this need. These should form the core of a future research agenda for intelligent interaction design. [source] | |||||||||||||