bluuebunny/crossref_metadata_2025 huggingface dataset:
Amygdala Kindling in Proechimys guyannensis Rat: An Animal Model of Resistance to Epilepsy
Authors: De Amorim Carvalho Reinaldo , Arida Ricardo Mario , Cavalheiro Esper A.
Published: March 2003

Summary:  Purpose: This study examined the effect of amygdala kindling development in Proechimys guayannensis rat, a common rodent of the Amazon basin.

Methods: Adult male P. guayannensis animals (n = 43) and adult male Wistar rats (n = 14) were submitted to electrical amygdala kindling.

Results: From 43 Proechimys rats submitted to the kindling process, only three animals reached stage 5 of kindling. During the kindling development (stages 4–5), these animals had behavioral alterations different from those observed in Wistar rats. A longer time spent in stages 1–3 and 5 and longer afterdischarge duration in stages 1–4 was observed in the Proechimys group compared with the Wistar group. The number of wet‐dog shakes also was reduced in the Proechimys group during the kindling process.

Conclusions: These findings suggest natural endogenous inhibitory mechanisms in this animal species.
Hot‐Water Epilepsy
Authors: Satishchandra P.
Published: March 2003

Summary: Geographically specific epilepsy syndromes are of epidemiologic interest and may assist in understanding the pathogenic mechanism of epilepsy in general. Some may have a genetic basis with added environmental influence. Among these epilepsy syndromes in India is an interesting type of reflex seizure known as hot‐water epilepsy (HWE) and single small computed tomography (CT)‐enhancing lesions (SSCTLs).
Nocturnal Sleep‐Disturbing Nicotine Craving: A Newly Described Symptom of Extreme Nicotine Dependence
Authors: Rieder Anita , Kunze Ursula , Groman E. , Kiefer Ingrid , Schoberberger R.
Published: March 2003

Summary: In our research on smoking and nicotine dependence we have noticed a sleep disturbance, which is a further symptom of extreme nicotine dependence. We call this symptom “nocturnal sleep‐disturbing nicotine craving” (NSDNC).  NSDNC is characterised by craving for cigarettes during the individual sleep times. The smoker awakes (one or several times per week) during his regular sleep time, and has to smoke a cigarette before he/she continues sleeping. This symptom can be explained by the decreasing nicotine levels during the sleep time, which results in nicotine craving. However, NSDNC should be carefully separated from other sleep disturbances, or sleep disturbing events (nycturia, medication side effects), when nicotine craving is not the main reason for awakening.
Nierenlebendspende – Auswahlkriterien, Vorbereitung und Nachsorge
Authors: König P.
Published: March 2003

Zusammenfassung: Da in Österreich die durchschnittliche Wartezeit für eine Nierentransplantation immer noch mehr als 2 Jahre beträgt, ist die Frage der Lebendspende von großer Aktualität. Wir unterscheiden zwischen verwandten und nichtverwandten LebendspenderInnen, deren Auswahl nach medizinischen Kriterien und aufgrund emotionaler Verbundenheit erfolgt. In Österreich wurden 1967 die ersten drei Verwandtenspenden durchgeführt (OEDR). Seither wurden bis zum 31. 12. 2000 insgesamt 317 Nieren von LebendspenderInnen unter Blutsverwandten übertragen. Nichtverwandte Lebendspenden wurden 1982 und 1990 je einmal, seit dem Jahr 1995 in jährlich steigender Zahl bis 31. 12. 2000 österreichweit insgesamt 47 Mal durchgeführt.  Das United Network for Organ Sharing (3) hat über einen Zeitraum von 4 Jahren (1995 – 1998) das 10‐Jahres‐Transplantatfunktionsüberleben bei über 30 000 Nierentransplantatempfängern von HLA (Human Leucocyte Antigen)‐identen Zwillingen, nichtverwandten Lebendspenden, Elternspenden und Leichennieren aufgeschlüsselt. Dabei hat sich gezeigt, dass erwartungsgemäß die HLA‐identen Zwillinge (n = 1 581) mit 81 % die besten Ergebnisse erzielten, gefolgt von den nichtverwandten SpenderInnen (n = 1 704) trotz oft schlechtem HLA‐Match mit 67 % vor den Elternspenden (n = 2 428) mit 62 % und den Leichennieren (n = 26 178) mit 50 %. Somit scheinen sowohl medizinische Aspekte wie auch Einflüsse aus dem psychosozialen Umfeld für den Transplantationserfolg ausschlaggebend zu sein. Daher kann es durchaus ratsam sein, bei der Auswahl aus mehreren möglichen LebendspenderInnen auf Grund emotionaler Gründe ein schlechteres HLA‐Match zu akzeptieren. Diese Überlegung fordert strenge Auswahlkriterien, und die Vorbereitung und Nachsorge bedarf größter Sorgfalt. Die in der vorliegenden Arbeit angeführten Kriterien sollen als Richtlinien dienen, die Entscheidungen für eine Lebendspende hilfreich zu unterstützen, ohne ein individuelles Vorgehen nach kritischer Meinungsbildung unter Einbeziehung der Betroffenen, nämlich Spender und Empfänger, sowie ihrer Berater – Nephrologe, Psychotherapeut und Transplantationschirurg – selbstverständlich auszuschließen. Zugleich darf man es auf keinen Fall unterlassen, mit größtmöglichem Einsatz weiterhin die Nutzung von Leichennieren zu intensivieren, um alle zur Verfügung stehenden Ressourcen optimal zu nutzen, dialysepflichtige Patienten mit einem Nierentransplantat zu versorgen.
Sex differences in foraging behaviour and oviposition site preference in an insect predator, Orius sauteri
Authors: Nakashima Yoshitaka , Hirose Yoshimi
Published: March 2003

The effects of patch quality on the foraging behaviour of an anthocorid predator Orius sauteri (Poppius) were compared between sexes. Prior experience in patches was also studied to determine whether this was a factor affecting oviposition decisions. Patch quality affected patch residence time differently for the two sexes; females stayed much longer in a patch with prey (60 Thrips palmi larvae) than a patch without prey, while males did not remain in any patch for extended periods. Most of the females remained in or moved to patches with prey, whereas males dispersed, irrespective of patch quality. Both females released in patches with prey and females released in patches without prey deposited more eggs per hour in patches with prey than in patches without prey. Females released in patches without prey laid eggs in patches with prey at higher rates than did females released in patches with prey. Causes for the sex difference in patch residence time and allocation are discussed in relation to optimal foraging theory. The significance of selective oviposition and the role of experience in oviposition decisions within heterogeneous environments are also discussed.
Egg load and adaptive superparasitism in Anaphes nitens, an egg parasitoid of the Eucalyptus snout‐beetle Gonipterus scutellatus
Authors: Carbone Serena Santolamazza , Rivera Adolfo Cordero
Published: March 2003

We studied egg production and the occurrence of adaptive superparasitism in Anaphes nitens, an egg parasitoid of the Eucalyptus snout beetle Gonipterus scutellatus. First, we determined whether A. nitens females were synovigenic or pro‐ovigenic. Newly emerged females were allowed to lay eggs alone during 3 days on six fresh egg capsules. A first group of females (n = 25) were killed by freezing and the remaining females (n = 21) were maintained during two extra days with food, but without hosts. Their fecundity was measured by dissection of host eggs and females’ ovarioles. We found that the second group of females increased their fecundity by about 20%, suggesting they were weakly synovigenic. To test for the occurrence of adaptive superparasitism in relation to competitors’ density, we compared the oviposition behaviour of females kept alone, in pairs, or in groups of four during patch visit. Results indicated that the females superparasited significantly more often in this last treatment. Synovigeny and the ability to modulate the use of superparasitism could be mentioned as important attributes that allow A. nitens to efficiently control the pest population.
Mate location in the green capsid bug, Lygocoris pabulinus
Authors: Drijfhout Falko P. , Groot Astrid T. , Van Beek Teris A. , Visser J. Hans
Published: March 2003

Headspace extracts from female Lygocoris pabulinus (L.) (Heteroptera: Miridae) as well as female leg extracts attracted male L. pabulinus in Y‐track olfactometer bioassays. In contrast, only female leg extracts were active in the vibration bioassay. Male extracts had no activity at all in either bioassay. When the female leg extract was analysed by coupled gas chromatography‐electroantennography (Z)‐9‐pentacosene and (Z)‐7‐pentacosene were EAD‐active. (Z)‐9‐Pentacosene and sometimes (Z)‐7‐pentacosene were also observed in female headspace extracts. EAG responses could be obtained for (Z)‐9‐pentacosene. A mixture of (Z)‐9‐pentacosene and (Z)‐7‐pentacosene in the ratio 5 : 1 elicited vibration behaviour in males. The results indicate that these alkenes are important cues for male L. pabulinus in mate location behaviour.
Pruritus – Pathophysiologie, Klinik und Therapie – Eine Übersicht
Authors: Ständer Sonja , Weisshaar Elke , Steinhoff Martin , Luger Thomas A. , Metze Dieter
Published: March 2003

Pruritus ist eine unangenehme, selbständige Sinneswahrnehmung der Haut, die mit dem unstillbaren Verlangen einer mechanischen Reizbeantwortung einhergeht. Sie dient als physiologische Nozizeption dazu, schädigende Noxen wie Parasiten oder Pflanzenbestandteile von der Haut zu entfernen. Als Erkrankungssymptom vieler dermatologischer und systemischer Erkrankungen tritt Pruritus häufig in sehr quälender und therapierefraktärer Form auf. Chronischer Pruritus beeinträchtigt, ähnlich wie Schmerz, das Allgemeinbefinden des Patienten erheblich und kann im Extremfall zu physischer und psychischer Erschöpfung führen. Bis in die 90er Jahre des letzten Jahrhunderts existierte die theoretische Vorstellung, Pruritus sei ein unterschwelliger Schmerzreiz. Erst in den letzten Jahren konnte Pruritus als eigenständige, von Schmerz unabhängige Sinneswahrnehmung definiert werden mit eigenen Mediatoren, spinalen Reizleitungsbahnen und zerebralen Wahrnehmungsarealen. Diese Erkenntnisse führten zur Entwicklung neuer vielversprechender Therapien. In diesem Übersichtsartikel sollen Pathophysiologie, klinische Formen und Therapiansätze bei Pruritus dargestellt werden.
Shape optimization of critical stiffener runouts for F‐111 airframe life extension
Authors: Heller M. , Mcdonald M. , Burchill M. , Watters K. C.
Published: March 2003

ABSTRACT Optimal rework shapes for the most critical stiffener runout fatigue locations in the F‐111 wing pivot fitting have been determined using a recently developed finite‐element‐based gradient‐less shape optimization procedure. The resulting precise free‐form shapes render the local notch stress distributions near uniform and typically provide a 30–40% reduction in peak elastic stresses as compared to the current rework shapes that exist for aircraft in service with the Royal Australian Air Force. The present numerical results are also consistent with recent preliminary experimental results, and a significant program of further validation testing is envisaged. Hence it is expected that the stress reductions predicted in the present work will be sufficient to provide a basis for extending inspection intervals by at least a factor of two; from 500 to 1000 h. Implementation of such an extension to the F‐111 fleet in service with the Royal Australian Air Force would provide a very significant maintenance cost saving. The anticipated reduction in local crack growth rates would also allow achievement of the planned withdrawal date for the aircraft.
HIV-1 Envelope Proteins Complete Their Folding into Six-helix Bundles Immediately after Fusion Pore Formation
Authors: Markosyan Ruben M. , Cohen Fredric S. , Melikyan Grigory B.
Published: March 2003

Fusion proteins of many viruses, including HIV-1 envelope protein (Env), fold into six-helix bundle structures. Fusion between individual Env-expressing cells and target cells was studied by fluorescence microscopy, and a temperature jump technique, to determine whether folding of Env into a bundle is complete by the time fusion pores have formed. Lowering temperature to 4°C immediately after a pore opened halted pore growth, which quickly resumed when temperature was raised again. HIV gp41-derived peptides that inhibit bundle formation (C34 or N36) caused the cold-arrested pore to quickly and irreversibly close, demonstrating that bundle formation is not complete by the time a pore has formed. In contrast, lowering the temperature to an intermediate value also halted pore growth, but the pore was not closed by the bundle-inhibiting peptides, and it enlarged when temperature was again elevated. This latter result shows that bundle formation is definitely required for the fusion process, but surprisingly, some (if not all) bundle formation occurs after a pore has formed. It is concluded that an essential function of the bundle is to stabilize the pore against collapse and ensure its growth.
The Fission Yeast Meiotic Regulator Mei2p Forms a Dot Structure in the Horse-Tail Nucleus in Association with thesme2Locus on Chromosome II
Authors: Shimada Tadayuki , Yamashita Akira , Yamamoto Masayuki
Published: March 2003

Fission yeast Mei2p is an RNA-binding protein essential for induction of both premeiotic DNA synthesis and first meiotic division. Mei2p forms a dot structure at an apparently fixed position in the horse-tail nucleus during meiotic prophase. This dot formation requires a meiosis-specific RNA species, meiRNA, which is indispensable for meiosis I, and the emergence of the dot is an indicator of the ability of the cell to perform meiosis I. Herein, we have sought the identity of this dot. Analyses using chromosome segregation in haploid meiosis, reciprocal translocation of chromosomes, and gene translocation have led us to conclude that the Mei2p dot is in association with the sme2 gene on the short arm of chromosome II, which encodes meiRNA. Transcripts of sme2, rather than the DNA sequence of the gene, seem to be the determinant of the localization of the Mei2p dot. However, evidence suggests that the dot may not be a simple reflection of the attachment of Mei2p to meiRNA undergoing transcription. We speculate that the Mei2p dot is a specialized structure, either to foster the assembly of Mei2p and meiRNA or to perform some unidentified function indispensable for meiosis I.
The development of the COBISS system and services in Slovenia
Authors: Seljak Marta , Seljak Tomaž
Published: March 2003

This paper presents an overview of recent developments of the Co‐operative Online Bibliographic System and Services (COBISS) system in Slovenia. The COBISS system interconnects over 250 of the largest Slovenian libraries into a uniform Slovenian library information system. Also, COBISS is used by other independent library systems in some of the countries on the territory of the former Yugoslavia. The development of the COBISS shared cataloguing system and services runs parallel with the second software generation (COBISS2) and the new, object‐oriented technological platform (COBISS3). On COBISS2 the authority control and other services were introduced, whereas on COBISS3 the development of the interlibrary loan applications, acquisitions and other services is being carried out.
EuroStudies: introducing the new European Studies Section of the Social Science Information Gateway
Authors: Woodcock Louise , Biddiscombe Richard
Published: March 2003

Outlines the reasons behind the development of the EuroStudies section the Social Science Information Gateway (SOSIG) and discusses the extent of the database coverage and the changes that have had to be made to absorb the new subject area.
Inequality, inflation, and central bank independence
Authors: Dolmas Jim , Huffman Gregory W. , Wynne Mark A.
Published: March 2003

What can account for the different contemporaneous inflation experiences of various countries, and of the same country over time? We present an analysis of the determination of inflation from a political economy perspective. We document a positive correlation between income inequality and inflation and then present a theory of the determination of inflation outcomes in democratic societies that illustrates how greater inequality leads to greater inflation, owing to a desire by voters for wealth redistribution. We conclude by showing that democracies with more independent central banks tend to have better inflation outcomes for a given degree of inequality. JEL Classification E5, H0

Inégalité, inflation et l'indépendance de la banque centrale. Quels sont les facteurs qui pourraient expliquer les expériences inflationnistes tellement différentes des divers pays dans le passé récent, et l'expérience tellement différente d'un pays donné dans le temps? Les auteurs analysent ce problème de la détermination du taux d'inflation dans une perspective d'économie politique. Ils déterminent qu'il y a une corrélation positive entre l'inégalité et l'inflation, et présentent une théorie de la détermination de l'inflation dans les sociétés démocratiques qui montre comment une inégalité plus grande entraîne une inflation plus grande à cause du désir des électeurs de demander une redistribution de la richesse. Le mémoire montre en terminant que les démocraties e´quipées de banques centrales plus indépendantes tendent à avoir de meilleurs résultats en terme d'inflation pour un degré d'inégalité donné.
Credit market imperfections and exchange rate variability
Authors: Ho Wai‐Ming
Published: March 2003

In this paper a two‐country overlapping generations model is presented in which the roles of financial factors in the international monetary transmission mechanism are studied and whether and how the two types of credit market imperfections, limited participation, and costly state verification may contribute to the high variability of exchange rates are examined. Liquidity effects generated by monetary disturbances are shown to have qualitatively similar effects on the world economy in the perfect information case and in the costly information case. However, quantitative differences provide dfferent predictions about the variability of economic variables in the world economy. JEL Classification: F31, F41

Ce mémoire présente un modèle de deux pays où les générations se chevauchent pour étudier le rôle des facteurs financiers dans le mécanisme de transmission monétaire international, et pour examiner si les deux types d'imperfection (participation limitée et contrôle étatique coûteux) peuvent contribuer à une grande variabilité des taux de change et de quelle manière. On montre que les effets de liquidité engendrés par les perturbations monétaires ont les mêmes effets qualitatifs sur l'économie mondiale que l'information soit parfaite ou coûteuse. Cependant, il y a des différences quantitatives. Ces différences suggèrent des écarts dans les prévisions quant à la variabilité des variables économiques dans l'économie mondiale.
Union bargaining power, relative wages, and efficiency in Canada
Authors: Fisher Timothy C.G. , Waschik Robert G.
Published: March 2003

We use a computable general equilibrium model incorporating trade unions, efficient Nash contracts, existing distortions, and international trade to measure the deadweight loss in Canada arising from the ability of unions to raise wages above competitive levels. The model incorporates two features new to CGE analysis: parameterization of union bargaining power and variations in union preferences. Estimates indicate the deadweight loss to be no more than 0.04 per cent of GNP. However, the small aggregate effect masks considerable adjustments at the industry level, in imports and exports, and in the distribution of income. Adjustments are also larger with employment‐oriented unions.

Pouvoir de négociation des syndicats, salaires relatifs et efficacité au Canada. Les auteurs utilisent un modèle d'équilibre général calculable qui prend en compte les syndicats ouvriers, des contrats efficients à la Nash, les distorsions existantes, et le commerce international pour mesurer les pertes de bien‐être au Canada attribuables au fait que les syndicats engendrent des niveaux de salaires au dessus des niveaux concurrentiels. Le modèle incorpore deux éléments inédits: la paramétrisation du pouvoir de négociation des syndicats et les variations dans les préférences des syndicats. Les résultats indiquent que les pertes de bien‐être ne dépassent pas 0,04 pourcent du PIB. Cependant, ce petit effet agrégé masque des ajustements substantiels au niveau de l'industrie, dans les importations et exportations, et dans la répartition des revenus. Les ajustements sont aussi plus importants quand les syndicats mettent l'accent sur l'emploi.
Needs‐based health care funding: implications for resource distribution in Ontario
Authors: Bedard Kelly , Dorland John , Gregory Allan W. , Roberts Joanne
Published: March 2003

Capitation models have been suggested as an alternative to funding methods based on historical utilization patterns. Capitation funding distributes esources to regions or programs according to their population, adjusted for the age and gender composition and relative need. The most commonly used relative needs measure is the Standardized Mortality Ratio (SMR). This paper compares the distribution of resources in Ontario implied by a variety of capitation formula. Another aspect of this research is to design a mechanism that translates the SMR into a funding allocation index. We specify a non‐linear model to capture the relationship between current expenditures and the SMR while controlling for historical utilization factors. In contrast to previous work, in which a linear relationship between expenditures and need was assumed, our estimates suggest that the relationship may actually be highly non‐linear. This non‐linearity ncreases transfers to regions of relative need relative to a linear capitation program. JEL Classification: I0, H51

On a suggéré des modèles de financement per capita des soins de santé pour remplacer les méthodes de financement fondées sur les patterns historiques d'utilisation. Cette solution de rechange distribuerait les ressources aux régions et programmes selon la population (avec des ajustements pour tenir compte de la structure 'âges, de sexes, et de besoins relatifs). La mesure la plus commune des besoins relatifs est le taux de mortalité standardisé (TMS). Ce mémoire compare la répartition des ressources en Ontario qui découlerait de l'emploi d'une variété de formules. On tente aussi de construire un mécanisme qui traduise le TMS en un indice d'allocation des fonds. Les auteurs construisent un odèle non‐linéaire qui saisit la relation entre TMS et épenses courantes tout en normalisant pour tenir compte des facteurs historiques d'utilisation. Contrairement aux résultats des travaux antérieurs qui postulaient une relation linéaire entre épenses et besoins, les résultats de cette étude uggèrent que cette relation peut être fortement non‐linéaire, et que cette non‐linéarité tend à ccroître les transferts aux régions qui ont les besoins les plus grands.
Switching costs and screening efficiency of incomplete contracts
Authors: Bac Mehmet
Published: March 2003

We study the role of switching costs in a dynamic buyer‐seller relationship where quality is not contractible and the sellers retain private information about their quality‐relevant abilities. In this environment buyer switching costs increase the seller's bargaining power in negotiations for the second contract, but they also induce the seller to improve quality during the first ontract, in signalling his type. The overall effect is to enhance efficiency and ncrease the buyer's welfare. This beneficial effect stems from the link between quality, the buyer's posterior beliefs, and ex post distribution of bargaining power as a function of the switching cost. JEL Classification: L14

L'auteur étudie le rôle des coûts de commutation dans une relation dynamique acheteur‐vendeur où la qualité de la prestation ne peut être partie du contrat, et où les vendeurs peuvent rationner l'information quant à leurs compétences à livrer un produit de qualité. Dans ce contexte, les coûts de commutation de l'acheteur accroissent le pouvoir de marchandage du vendeur dans la négociation du second contrat, mais ils peuvent aussi inciter le vendeur à améliorer la qualité au cours du premier contrat pour signaler ses compétences à l'acheteur. L'effet global est d'améliorer l'efficacité et d'accroître le bien‐être de l'acheteur. Cet effet bénéfique émerge du lien entre la qualité, les croyances de l'acheteur a posteriori, et la répartition du pouvoir de négociation ex post en tant que fonction des coûts de commutation.
Restructuring Appalachian Manufacturing in 1963–1992: The Role of Branch Plants
Authors: Jensen J. Bradford , Glasmeier Amy K.
Published: March 2003

This paper uses the Longitudinal Research Database (LRD),a unique, detailed, plant‐level database that covers the entire U.S. manufacturing sector in five‐year intervals to examine how the manufacturing sector in Appalachia has evolved over the past thirty years (from 1963 to 1992). The research focuses on three questions:1) Is the Appalachian Region attracting new manufacturing plants at the same rate as the rest of the country? 2) Does Appalachian manufacturing employment exhibit low wage, low productivity characteristics, compared with the rest of the country? 3) Is Appalachia still heavily reliant on branch plants? The results show the manufacturing base of Appalachia in 1992 looks very much the same as it did in 1967. Compared to the rest of the country, Appalachian manufacturing is still more reliant on branch plants and is characterized by lower wage and lower productivity establishments. This result is not due to a lack of entry—manufacturing plant entry rates and manufacturing job formation associated with entrants in Appalachia are only slightly lower than for the U.S. as a whole. Job destruction rates caused by exits are actually lower than in the U.S. as a whole.
Multimodal Interaction for Information Access: Exploiting Cohesion
Authors: Zancanaro Massimo , Stock Oliviero , Strapparava Carlo
Published: March 2003

Multimodality is a powerful concept for dealing with dialogue cohesion in a human–computer natural language (NL)‐centered system. This work is a modest step toward more effective exploitation of the potentially large bandwidth of communication provided by this situation. The relations between exploration, navigation, and NL‐based communication are discussed in general and with reference to two prototypes. Light cognitive load feedback and direct manipulation are proposed so that user and system can cooperate in mutually establishing the structure of the ongoing dialogue. The main points are: (i) use of an appropriate dialogue structure to constrain inference in the anaphora resolution process; (ii) use of a graphical representation of the structure, to limit the problem of opacity; (iii) allowance for the possibility of direct manipulation on this representation, to avoid the necessity of operating linguistically at the metalevel. The context of the work is within NL‐centered multimodal information access systems, in which basic entities are pairs (most commonly question and answer). A dialogue model is provided by a modified version of the centering model; it is both sufficiently simple to be displayed in an intuitive fashion on the screen, and sufficiently powerful to give accurate results. An extension of the discourse model, oriented to the treatment of deixis, is also proposed. Finally, steps toward an overall approach to the integration of navigational and mediated aspects of interaction are discussed.
Representing and Reasoning about Motion in a Two‐Dimensional World
Authors: Pang Wanlin , Trudel Andrè
Published: March 2003

We present a point‐based spatiotemporal first‐order logic for representing the qualitative and quantitative spatial temporal knowledge needed to reason about motion in a two‐dimensional space. A feature of the logic is the uniform treatment of space and time. The knowledge of a simplified world, a two‐dimensional street network with active traffic lights, is represented, and the reasoning problem of how a robot moves from one place to another in the world is formalized with the proposed logic.
The Foundations of Taxonomic Encoding
Authors: Fall Andrew
Published: March 2003

Taxonomies (partially ordered sets and lattices) are important in many areas of computing science, particularly object‐oriented languages, machine learning, and knowledge representation. Taxonomic encoding strives to enhance the efficiency of taxonomic representation and use, which becomes increasingly important as the size of taxonomies grows. In this paper, we describe a formal structure, called a spanning set, in which taxonomic encoding techniques can be characterized. Any taxonomic encoding scheme implements a mapping from the original ordered set into a structure, such as the lattice of bit‐vectors or logical terms, in which operations can be performed efficiently. We analyze the fundamental properties any such mapping must satisfy in order to preserve subsumption, joins, or meets. Spanning sets are an abstract framework within which we portray and compare existing encoding techniques, and provide a context in which new encoding problems can be analyzed, leading to existing, related algorithms or, using other results we develop in this paper, guiding the development of new algorithms. We also explore the limits of minimal‐sized encodings, proving a lower bound for simple forms of encoding and showing that, in general, finding minimal‐sized encodings is NP‐hard. This paper can thus be viewed as both a synthesis of current research in taxonomic encoding and a repository of new results and directions for encoding as viewed from the perspective of spanning sets.
Retrieving Domain‐Specific Collocations by Co‐occurrences and Word Order Constraints
Authors: Shimohata Sayori , Sugio Toshiyuki , Nagata Junji
Published: March 2003

In this paper, we describe a method for automatically retrieving collocations from large text corpora. This method comprises the following stages: (1) extracting strings of characters as units of collocations, and (2) extracting recurrent combinations of strings as collocations. Through this method, various types of domain‐specific collocations can be retrieved simultaneously. This method is practical because it uses plain text with no specific‐language‐dependent information, such as lexical knowledge and parts of speech. Experimental results using English and Japanese text corpora show that the method is equally applicable to both languages.
Constructing and Utilizing a Model of User Preferences in Collaborative Consultation Dialogues
Authors: Carberry Sandra , Chu‐Carroll Jennifer , Elzer Stephanie
Published: March 2003

A natural language collaborative consultation system must take user preferences into account. A model of user preferences allows a system to appropriately evaluate alternatives using criteria of importance to the user. Additionally, decision research suggests both that an accurate model of user preferences could enable the system to improve a user's decision‐making by ensuring that all important alternatives are considered, and that such a model of user preferences must be built dynamically by observing the user's actions during the decision‐making process. This paper presents two strategies: one for dynamically recognizing user preferences during the course of a collaborative planning dialogue and the other for exploiting the model of user preferences to detect suboptimal solutions and suggest better alternatives. Our recognition strategy utilizes not only the utterances themselves but also characteristics of the dialogue in developing a model of user preferences. Our generation strategy takes into account both the strength of a preference and the closeness of a potential match in evaluating actions in the user's plan and suggesting better alternatives. By modeling and utilizing user preferences, our system is able to fulfill its role as a collaborative agent.
Experimentation‐Driven Knowledge Acquisition for Planning
Authors: Tae Kang Soo , Cook Diane J. , Holder Lawrence B.
Published: March 2003

Knowledge engineering for planning is expensive and the resulting knowledge can be imperfect. To autonomously learn a plan operator definition from environmental feedback, our learning system WISER explores an instantiated literal space using a breadth‐first search technique. Each node of the search tree represents a state, a unique subset of the instantiated literal space. A state at the root node is called a seed state. WISER can generate seed states with or without utilizing imperfect expert knowledge. WISER experiments with an operator at each node. The positive state, in which an operator can be successfully executed, constitutes initial preconditions of an operator. We analyze the number of required experiments as a function of the number of missing preconditions in a seed state. We introduce a naive domain assumption to test only a subset of the exponential state space. Since breadth‐first search is expensive, WISER introduces two search techniques to reorder literals at each level of the search tree. We demonstrate performance improvement using the naive domain assumption and literal‐ordering heuristics. To learn the effects of an operator, WISER computes the delta state, composed of the add list and the delete list, and parameterizes it. Unlike previous systems, WISER can handle unbound objects in the delta state. We show that machine‐generated effects definitions are often simpler in representation than expert‐provided definitions.
Constraint Reasoning about Repeating Events: Satisfaction and Optimization
Authors: Morris Robert A. , Khatib Lina
Published: March 2003

Effective manipulation of temporal information about periodic events is required for solving complex problems such as long‐range scheduling or querying temporal information. Furthermore, many problems involving repeating events involve the optimization of temporal aspects of these events (e.g., minimizing make‐span in job‐shop scheduling). In this paper, a constraint‐based formulation of reasoning problems with repeating events is presented, and its complexity is analyzed for a range of problems. Optimization constraints are interpreted formally using the Semiring CSPs (SCSP) representation of optimization in constraint reasoning. This allows for familiar algorithms such as branch‐and‐bound to be applied to solving them.
Interactive, Text‐Based Summarization of Multiple Documents
Authors: Stein Gees C. , Strzalkowski Tomek , Wise G. Bowden
Published: March 2003

This paper describes a system for the summarization of multiple text‐only news‐like documents. We address two main issues: clustering of documents in order to find the main topics that should be mentioned in the multidocument summary and organization of the information in order to create a summary that presents the information in a logical way and is easy to read. The system is based on a single‐document summarizer that uses text‐extraction.
Competence Models and the Maintenance Problem
Authors: Smyth Barry , McKenna Elizabeth
Published: March 2003

Case‐based reasoning (CBR) systems solve problems by retrieving and adapting the solutions to similar problems that have been stored previously as a case base of individual problem solving episodes or cases. The maintenance problem refers to the problem of how to optimize the performance of a CBR system during its operational lifetime. It can have a significant impact on all the knowledge sources associated with a system (the case base, the similarity knowledge, the adaptation knowledge, etc.), and over time, any one, or more, of these knowledge sources may need to be adapted to better fit the current problem‐solving environment. For example, many maintenance solutions focus on the maintenance of case knowledge by adding, deleting, or editing cases. This has lead to a renewed interest in the issue of case competence, since many maintenance solutions must ensure that system competence is not adversely affected by the maintenance process. In fact, we argue that ultimately any generic maintenance solution must explicitly incorporate competence factors into its maintenance policies. For this reason, in our work we have focused on developing explanatory and predictive models of case competence that can provide a sound foundation for future maintenance solutions. In this article we provide a comprehensive survey of this research, and we show how these models have been used to develop a number of innovative and successful maintenance solutions to a variety of different maintenance problems.
Dynamics of Social Policy Change: A Korean Case Study from a Comparative Perspective
Authors: Joo Jaehyun
Published: March 2003

Most of the existing literature on dynamics of social policy change was developed against the background of the Western liberal democratic political regimes. This study examines the application of these existing studies to the experience of the East Asian newly industrialized countries. Special attention is paid to two social policy problems of South Korea—the problems of low wage levels and compensation for pollution victims. Because of authoritarian government and a strongly autonomous state, the Korean cases show a pattern of policy changes primarily driven by a particular set of interests—the state elites' perceived political survival needs and their reputation in international society, with environmental factors and policy legacies playing a supplementary role. Also, in spite of state elites' reluctance to adopt social policy measures, the Korean cases show a pattern of policy developments away from the residual towards the institutional model. The results of this study suggest that, despite some differences between the social policy systems of the East Asian countries, the existing literature on social policy change has considerable potential for application to those countries. At the same time, however, the literature has a limited capacity for fully accommodating the East Asian experience, which stimulates political scientists to develop generalizations in a wider international context.
Global Governance through Private Organizations
Authors: Ronit Karsten , Schneider Volker
Published: March 2003

Governance at international and global levels is not only provided through states and markets but also through a variety of private organizations. The business world is well represented through this kind of organization and contributes to global governance through self‐regulation across a number of industries. This article examines these efforts in the encompassing organization of global commerce, in the pharmaceutical industry and among dye stuffs producers. Smaller organizations are generally better suited to monitor compliance and impose sanctions on members violating the codes and norms behind self‐regulation. Even small organizations, however, are confronted with problems and there is also evidence of large and very complex organizations having established effective mechanisms as alternatives to public regulation. These experiences can be built into theories on self‐regulation as a form of global governance.
Enterprise Reorganization and Social Insurance Reform: The Development of Early Retirement in France and Germany
Authors: Mares Isabela
Published: March 2003

What explains the decline in the labor force participation rates of elderly workers at the end of their working lives? Why have governments been unable to revert towards early exit from the labor market? This paper provides an actor‐centered analysis of the development of early retirement, highlighting the political negotiation among unions, employers, and governments over the distribution of the costs of these measures and the division of control over the initiation of these policies. By analyzing developments in France and Germany, the paper points to the failure of these negotiations to arrive at policy outcomes that close off the labor shedding of large firms.
Part‐time Nurses: The Effect of Work Status Congruency on Job Attitudes
Authors: Mantler Keil Janet , Armstrong‐Stassen Marjorie , Cameron Sheila , Horsburgh Martha
Published: March 2003

Nous avons mene´ 2 e´tudes (N=204 et N=251) pour examiner comment la congruence de statut au travail (pre´fe´rence pour le travail a` temps partiel par opposition au travail a` temps plein) influence les attitudes vis a` vis de l’emploi et les re´actions aux changements organisationnels des infirmie`res a` temps partiel employe´es dans le cadre d’un hôpital. Les re´sultats de l’analyse discriminante ont indique´ un effet important de la congruence de statut au travail pour les deux e´chantillons. Compare´es aux infirmie`res qui ont un statut non congruent (c’est a` dire une pre´fe´rence pour le travail a` temps plein), les infirmie`res qui ont un statut au travail congruent (pre´fe´rence pour le travail a` temps partiel) e´taient plus age´es et plus satisfaites des re´compenses financie`res de leurs emplois. Inversement, les infirmie`res dont le statut au travail e´tait non congruent signalaient une plus grande satisfaction relative au travail qu’elles accomplissaient. Il n’y avait pas de diffe´rence notable quant a` la satisfaction globale de leur emploi, quant a` la recherche d’un coping de fuite et l’intention de changer d’emploi. Enfin, il y avait des diffe´rences entre les deux e´chantillons concernant l’inse´curite´ de l’emploi et l’utilisation de strate´gies visant a` controler la situation, ce qui e´tait probablement due aux changements du syste`me de sante´ relatifs au moment de ces e´tudes.

We conducted two studies (N=204 and N=251) to examine how work status congruency (preference to work part‐time versus full‐time) influences the job attitudes and reactions to organisational restructuring of part‐time nurses employed in a hospital setting. The discriminant function analysis results indicated a significant effect for work status congruency for both samples. Compared with nurses with an incongruent work status (i.e. who would have preferred to work full‐time), nurses with a congruent work status (i.e. preferred to work part‐time) were older and more satisfied with the financial rewards of their jobs. Conversely, nurses with an incongruent work status reported greater satisfaction with the kind of work they were performing. There were no significant differences for overall job satisfaction, escape coping, and turnover intention. Finally, there were differences between the samples for job insecurity and use of control‐oriented coping strategies, most likely related to changes in the health‐care system at the time of the second study.
Procrastination: Self‐regulation in Initiating Aversive Goals
Authors: Van Eerde Wendelien
Published: March 2003

Procrastination is a common phenomenon that is easily recognised as one of the behaviours involved in not doing and avoiding work. However, work motivation theories have not devoted much attention to why people don’t do things at work. Just as the study of abnormal behaviour is used to understand normal behaviour, so can the study of procrastination enhance the understanding of self‐regulation. In this paper, procrastination is defined as the avoidance of the implementation of an intention. It is characterised by the avoidance of the intention and the preference for behaviour or thoughts that distract from the aversiveness of the intention. Individual difference variables, processes, and conditions are identified. Strategies to overcome procrastination are suggested.
Effective Leadership and Culture in Iran: An Empirical Study
Authors: Dastmalchian Ali , Javidan Mansour , Alam Kamran
Published: March 2003

On analyse dans cet article les caractéristiques du leadership efficace en Iran, puis on envisage les liens possibles entre ce profil de leadership et les dimensions culturelles du pays. A partir des données fournies par 300 managers provenant de plus de 60 organisations relevant de trois secteurs industriels, on commence par utiliser les dimensions du projet GLOBE pour évaluer la culture iranienne dont les scores sont comparés à ceux d’autres pays. S’appuyant à la fois sur l’emic et l’etic du leadership, les auteurs développent sept dimensions du leadership: encourageant, dictatorial, visionnaire, familial, modeste, loyal et réceptif. Ils soutiennent que certaines de ces dimensions traduisent les aspects universels (ou etic) du leadership (éncourageant, dictatorial), alors que d’autres procèdent de l’emic, c’est‐à‐dire de la spécificité culturelle du leadership (modeste, familial, loyal). Les résultats sont discutés en terme de positionnement de la culture iranienne entre des entrelacements fondamentaux et des traditions culturelles complexes. On aborde enfin la question des retombées sur les recherches à venir.
Lessons from Research on the Consequences of German Uniﬁcation: Continuity and Discontinuity of Self‐Efﬁcacy and the Timing of Psychosocial Transitions
Authors: Silbereisen Rainer K. , Wiesner Margit
Published: March 2003

La réuniﬁcation de l’Allemagne a offert une opportunité unique d’étudier les effets de changements sociaux radicaux sur le développement individuel. Dans cet article, nous présentons les principaux résultats de nos études sur les conséquences de la réuniﬁcation de l’Allemagne, ces recherches ayant utilisé des données provenant de larges échantillons à quota. Les résultats portent sur des aspects spéciﬁques du développement social et de la personnalité chez l’adolescent et le jeune adulte, soit l’efﬁcacité personnelle scolaire et l’âge à laquelle diverses transitions psychosociales ont lieu. Les résultats de nos études indiquent que les changements sociaux radicaux en Allemagne ont affecté plusieurs dimensions du développement social et de la personnalité, spécialement celles sujettes à l’inﬂuence de changement institutionnel. Cependant, les effets ont émergé plus tard qu’anticipé, ce qui est consistent avec la notion de “loose coupling” entre les contextes et les individus changeants (Elder, 1998a, 1998b). Des recherches plus détaillées sur les mécanismes de médiation et les facteurs modérateurs sont nécessaires dans le futur.

German uniﬁcation offered a unique opportunity to study the effects of radical societal change on individual development. In this article, we provide an overview of the central ﬁndings from our studies on the consequences of German uniﬁcation, which used data from large quota samples. Findings are reported for speciﬁc aspects of social and personality development in adolescence and young adulthood, namely, academic self‐efﬁcacy and the age at which various psychosocial transitions were accomplished. Our studies showed that the transformations in Germany affected several dimensions of social and personality development, especially those subject to the inﬂuence of institutional change. The effects, however, emerged later than anticipated, consistent with the notion of “loose coupling” between changing contexts and individuals (Elder, 1998a, 1998b). More in‐depth investigations of the mediating mechanisms and the moderating factors are needed in the future.
Property vs. Control: The State and Forest Management in the Indian Himalaya
Authors: Rangan Haripriya
Published: March 2003

The latest orthodoxy to emerge in environmental literature centres on the notion that state ownership of forests results in poor management and ecological degradation. Depending on their political persuasion, scholars, policy‐makers and activists either advocate privatization of state forests, or demand their transferral to local communities as solutions for promoting sustainable forest management. This article argues that such proposals are flawed because they assume that ownership status determines the ways in which resources are used and managed. It argues that an analytical distinction needs to be made between property and control for understanding the complex interplay of social, economic, political and ecological factors that influence forest stock, composition and quality. Through a historical analysis of the development of state forestry in the Indian Himalaya, the article shows how state ownership of forests does not result in the monolithic imposition of proprietary rights, but emerges instead as an ensemble of access and management regimes.