New Context (new + context)

Distribution by Scientific Domains


Selected Abstracts


The humerus of Panderichthys in three dimensions and its significance in the context of the fish,tetrapod transition

ACTA ZOOLOGICA, Issue 2009
Catherine A. Boisvert
Abstract The humerus of Panderichthys has been considered to represent a transitional form between that of tetrapodomorph fish such as Eusthenopteron and tetrapods such as Acanthostega. The previous description was based on flattened material and was analysed in the context of the few fossils known at the time. Since then, several new forms have been described such as Gogonasus, Tiktaalik and an isolated humerus from the Catskill Formation. The humeral morphology of Panderichthys rhombolepis and its interpretation in this new context are therefore reassessed with the help of a three-dimensional model produced with the mimics software based on a computed tomography scan of an unflattened specimen as well as comparisons with the originally described material. The humerus of Panderichthys displays a combination of primitive, derived, intermediate and unique characteristics. It is very similar to the morphology of Tiktaalik but when it differs from it, it is most often more derived despite the more basal phylogenetic position that Panderichthys occupies. What emerges from this study is a much more gradual transformation of the humerus morphology from fish to tetrapods and the ability to distinguish autapomorphies more easily. The picture is more complex than previously believed, with many morphological specializations probably reflecting the breadth of ecological specializations already present at the time. [source]


ADAPTIONISM,30 YEARS AFTER GOULD AND LEWONTIN

EVOLUTION, Issue 10 2009
Rasmus Nielsen
Gould and Lewontin's 30-year-old critique of adaptionism fundamentally changed the discourse of evolutionary biology. However, with the influx of new ideas and scientific traditions from genomics into evolutionary biology, the old adaptionist controversies are being recycled in a new context. The insight gained by evolutionary biologists, that functional differences cannot be equated to adaptive changes, has at times not been appreciated by the genomics community. In this comment, I argue that even in the presence of both functional data and evidence for selection from DNA sequence data, it is still difficult to construct strong arguments in favor of adaptation. However, despite the difficulties in establishing scientific arguments in favor of specific historic evolutionary events, there is still much to learn about evolution from genomic data. [source]


Entorhinal cortex lesions disrupt fear conditioning to background context but spare fear conditioning to a tone in the rat

HIPPOCAMPUS, Issue 2 2006
M. Majchrzak
Abstract Recent studies have shown that the integrity of the entorhinal cortex (EC) is not required for simple contextual conditioning. In background contextual conditioning, i.e., when a phasic cue is present during training, the involvement of the EC is still a matter of debate. Therefore, the present work further examines whether the EC is required for background contextual conditioning using a tone as the phasic cue. Rats sustaining either excitotoxic lesions of the EC or sham-lesions were trained with one of two procedures differing with respect to the predictive value of the tone: a paired procedure in which the tone perfectly predicts shock occurrence and overshadows context, and an unpaired procedure in which the predictive value of the tone is reduced. Conditioned fear was assessed by freezing responses during conditioning, reexposure to the training context, and reexposure to the tone in a new context. Postshock freezing was reduced in rats with entorhinal lesions. In all rats trained with the paired procedure, freezing to the context was low and freezing to the tone was high, suggesting that the tone has overshadowed the context during the conditioning session. The reverse pattern was observed with the unpaired procedure in sham-operated rats. In rats with entorhinal lesions trained with the unpaired procedure, freezing responses to the context was markedly reduced. In a new context, however, entorhinal-lesioned rats showed higher freezing scores than those of sham-lesioned rats. Freezing to the tone was unaffected by the lesion irrespective of the tone's predictive value. As a whole, these results support the notion that the EC is required for normal background contextual freezing. © 2005 Wiley-Liss, Inc. [source]


Time-dependent involvement of the dorsal hippocampus in trace fear conditioning in mice

HIPPOCAMPUS, Issue 4 2005
Ilga Misane
Abstract Hippocampal and amygdaloid neuroplasticity are important substrates for Pavlovian fear conditioning. The hippocampus has been implicated in trace fear conditioning. However, a systematic investigation of the significance of the trace interval has not yet been performed. Therefore, this study analyzed the time-dependent involvement of N-methyl- D -aspartate (NMDA) receptors in the dorsal hippocampus in one-trial auditory trace fear conditioning in C57BL/6J mice. The NMDA receptor antagonist APV was injected bilaterally into the dorsal hippocampus 15 min before training. Mice were exposed to tone (conditioned stimulus [CS]) and footshock (unconditioned stimulus [US]) in the conditioning context without delay (0 s) or with CS-US (trace) intervals of 1,45 s. Conditioned auditory fear was determined 24 h after training by the assessment of freezing and computerized evaluation of inactivity in a new context; 2 h later, context-dependent memory was tested in the conditioning context. NMDA receptor blockade by APV markedly impaired conditioned auditory fear at trace intervals of 15 s and 30 s, but not at shorter trace intervals. A 45-s trace interval prevented the formation of conditioned tone-dependent fear. Context-dependent memory was always impaired by APV treatment independent of the trace interval. The results indicate that the dorsal hippocampus and its NMDA receptors play an important role in auditory trace fear conditioning at trace intervals of 15,30-s length. In contrast, NMDA receptors in the dorsal hippocampus are unequivocally involved in contextual fear conditioning independent of the trace interval. The results point at a time-dependent role of the dorsal hippocampus in encoding of noncontingent explicit stimuli. Preprocessing of long CS-US contingencies in the hippocampus appears to be important for the final information processing and execution of fear memories through amygdala circuits. © 2005 Wiley-Liss, Inc. [source]


The effect of particle shape and grain-scale properties of shale: A micromechanics approach

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 11 2010
J. A. Ortega
Abstract Traditional approaches for modeling the anisotropic elasticity response of the highly heterogeneous clay fabric in shale have mainly resorted to geometric factors such as definitions of particles shapes and orientations. However, predictive models based on these approaches have been mostly validated using macroscopic elasticity data. The recent implementation of instrumented indentation aimed at probing nano-scale mechanical behaviors has provided a new context for characterizing and modeling the anisotropy of the porous clay in shale. Nanoindentation experimental data revealed the significant contribution of the intrinsic anisotropy of the solid clay to the measured elastic response. In this investigation, we evaluate both the effects of geometric factors and of the intrinsic anisotropic elasticity of the solid clay phase on the observed anisotropy of shale at multiple length scales through the development of a comprehensive theoretical micromechanics approach. It was found that among various combinations of these sources of anisotropy, the elastic response of the clay fabric represented as a granular ensemble of aligned effective clay particles with spherical morphology and anisotropic elasticity compares satisfactorily to nanoindentation and ultrasonic pulse velocity measurements at nano- and macroscopic length scales, respectively. Other combinations of sources of anisotropy could yield comparable predictions, particularly at macroscopic scales, at the expense of requiring additional experimental data to characterize the morphology and orientations of particles. Copyright © 2009 John Wiley & Sons, Ltd. [source]


,A Garland in Place of Ashes':1Transformative Spirituality and Mission in the Post-Modern and Secular Contexts

INTERNATIONAL REVIEW OF MISSION, Issue 2 2009
Peter Cruchley-Jones
In this paper I aim to explore not what is the so-called ,post-modern and secular context' but how the church responds to it, which is predominantly to blame it for ,decline'. Yet it may not be decline, it may be something else altogether. I am reflecting on a western/UK context, but within this are theological assumptions that characterize the wider church. So, having made some remarks on how to approach decline I will then explore some transformations of spirituality and mission that are responses to the post-modern and secular context. Underlying this is an attitude to ,spirituality' which is not about how we worship or our experience of the ,ethereal' but is about our ,capacity for life'. But, I want to maintain that nothing new or transformative can emerge until the church stops resenting and despairing of the context and change we are experiencing. Further, I am not convinced the church in the UK or the West is able to adapt to the strangeness of this new context and will seek always to bring it back under church control. But, I will then offer a post-modern image for transformative spirituality and mission that could leave its mark on the church. [source]


Influence of experience of treadmill exercise on visual perception while on a treadmill

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 2 2010
YOSHIKO YABE
Abstract A firm linkage exists between a motor command and its expected feedback. When we are exposed to a conflict between expected and actual feedback in a new context, we form a new linkage between action and perception, which may be further strengthened by prolonged experience. In this paper, we attempt to identify whether the linkage between treadmill locomotion and visual processing in relation to optic flow is strengthened in experienced users of treadmills. Yabe and Taga (2008) showed that ambiguous apparent motions are perceived to be moving downward more frequently when the stimuli are shown in front of the observers' feet on a treadmill when walking compared with when standing. Here, their experimental data was reanalyzed in relation to the experience of using the treadmill. The result revealed that habitual treadmill exercise reduced the difference in perceived direction of visual motion between the walking and standing conditions. It should be noted that the treadmill users showed perceptual "downward" bias for both the standing and walking conditions. The results suggest that treadmill users tend to activate the habitual linkage between treadmill locomotion and perception of optic ground flow even when they are just standing on a treadmill. [source]


Globalized Horticulture: The Formation and Global Integration of Export Grape Production in North East Brazil

JOURNAL OF AGRARIAN CHANGE, Issue 4 2010
BEN SELWYN
In horticulture contemporary globalization is associated with (at least) two connected processes , the concentration, centralization and expanding reach of global retailers and the emergence of numerous new sites of export horticulture specializing in fresh fruit and vegetable production aimed at metropolitan markets. Whilst there have been numerous studies about developmental impacts, conditions of labour, and producers' upgrading strategies within this new context, few studies give much, if any, space to explaining and analyzing the processes through which these new regions have come into being. This article provides a detailed account of the emergence and global integration of one of these new sites , the São Francisco valley grape branch in North East Brazil, within the context of the wider regional fruiticulture sector. It focuses on state activities and incentives, the provenance of grape producers and their organizations, and grape branch composition. [source]


Fish functional design and swimming performance

JOURNAL OF FISH BIOLOGY, Issue 5 2004
R. W. Blake
Classifications of fish swimming are reviewed as a prelude to discussing functional design and performance in an ecological context. Webb (1984a, 1998) classified fishes based on body shape and locomotor mode into three basic categories: body and caudal fin (BCF) periodic, BCF transient (fast-starts, turns) and median and paired fin (MPF) swimmers. Swimming performance and functional design is discussed for each of these categories. Webb hypothesized that specialization in any given category would limit performance in any other. For example, routine MPF swimmers should be penalized in BCF transient (fast-start propulsion). Recent studies offer much support for Webb's construct but also suggest some necessary amendments. In particular, design and performance compromises for different swimming modes are associated with fish that employ the same propulsor for more than one task (coupled, e.g. the same propulsor for routine steady swimming and fast-starts). For example, pike (BCF transient specialist) achieve better acceleration performance than trout (generalist). Pike steady (BCF periodic) performance, however, is inferior to that of trout. Fish that employ different propulsors for different tasks (decoupled, e.g. MPF propulsion for low-speed routine swimming and BCF motions for fast-starts) do not show serious performance compromises. For example, certain MPF low-speed swimmers show comparable fast-start performance to BCF forms. Arguably, the evolution of decoupled locomotor systems was a major factor underlying the adaptive radiation of teleosts. Low-speed routine propulsion releases MPF swimmers from the morphological constraints imposed by streamlining allowing for a high degree of variability in form. This contrasts with BCF periodic swimming specialists where representatives of four vertebrate classes show evolutionary convergence on a single, optimal ,thunniform' design. However, recent experimental studies on the comparative performance of carangiform and thunniform swimmers contradict some of the predictions of hydromechanical models. This is addressed in regard to the swimming performance, energetics and muscle physiology of tuna. The concept of gait is reviewed in the context of coupled and decoupled locomotor systems. Biomimetic approaches to the development of Autonomous Underwater Vehicles have given a new context and impetus to research and this is discussed in relation to current views of fish functional design and swimming performance. Suggestions are made for possible future research directions. [source]


Reasoning versus knowledge retention and ascertainment throughout a problem-based learning curriculum

MEDICAL EDUCATION, Issue 9 2009
Anne Collard
Context, Since 2000, problem-based learning (PBL) seminars have been introduced into the curriculum of medical studies at the University of Liège. We aimed to carry out a cross-sectional investigation of the maturational increase in biomedical reasoning capacity in comparison with factual knowledge retention throughout the curriculum. Methods, We administered a factual knowledge test (i.e. a true/false test with ascertainment degree) and a biomedical reasoning test (i.e. an adapted script concordance test [SCT]) to 104 students (Years 3,6) and a reference panel. The selected topic was endocrinology. Results, On the SCT, the students obtained higher scores in Years 5 and 6 than in Years 3 and 4. In Year 3, the scores obtained on SCT questions in a new context indicated transfer of reasoning skills. On the true/false test, the scores of Year 3 students were significantly higher than those of students in the other three year groups. A positive correlation between SCT scores and true/false test scores was observed only for students in Years 3 and 4. In each group, the ascertainment degree scores were higher for correct than for incorrect responses and the difference was calculated as an index of self-estimation of core knowledge. This index was found to be positively correlated to SCT scores in the four year groups studied. Conclusions, Biomedical reasoning skills are evidenced early in a curriculum involving PBL and further increase during training. This is accompanied by a decrease in factual knowledge retention. The self-estimation of core knowledge appears to be related to reasoning capacity, which suggests there is a link between the two processes. [source]


Triangular Contests and Caucus Rhetoric at the 1885 General Election*

PARLIAMENTARY HISTORY, Issue 2 2008
JAMES OWEN
This article explores the role played by late-Victorian political associations during parliamentary election campaigns. The central hypothesis is that party organisation, known popularly as the ,caucus', is best understood as a rhetorical device used by politicians and the press to gain legitimacy in the new context created by an expanded and quasi-democratic electorate. The hypothesis is tested by examining the 1885 general election campaigns in Nottingham West and Sheffield Central. Both constituencies witnessed a triangular contest whereby an ,additional' candidate, standing on a radical platform, entered the campaign and pursued a distinctly ,anti-caucus' agenda that was aimed primarily at the local Liberal Party Association. The manner in which the ,caucus' issue was articulated by all sides involved throws new light on the role played by party organisation during this period. While all sides described their association in a way that both defended and asserted its legitimacy, they equally used ,anti-caucus' rhetoric to diminish the credibility of their opponent's organisation, even though they were emulating the deeds they were denouncing. Indeed, it was those within official Liberalism that indulged in the most virulent ,anti-caucus' rhetoric. Thus, it is suggested that, with regard to the attitude of radicals towards official Liberalism, this ,anti-caucus' rhetoric reflected not a real popular resistance against party organisation or ,party', but simply intense competition and imitation between rival ,caucuses'. [source]


IUSAM-APdeBA: A higher education institute for psychoanalytic training

THE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 5 2009
Hector Ferrari
The history of the last century shows the almost constant presence of psychoanalysis in the academic setting and, simultaneously, the incredible absence of analytic training at the universities. This paper outlines the project of the Buenos Aires Psychoanalytic Association (APdeBA) to create a higher education institution of its own (IUSAM) specifically aimed at lodging psychoanalytic training within a university setting. The project was approved by the Argentine educational authorities in 2005 and received the economic support of the International Psychoanalytical Association (IPA). The academic structure of the university is described, whose goal is broadened to the interdisciplinary field of mental health with psychoanalysis as an integrating axis. Some of the characteristics of the traditional ,university model' as well as its relationship with psychoanalysis are pointed out. With the IUSAM, psychoanalytic training is not included as a part of an already established university, it rather creates a new one, with the support of a well-known psychoanalytical association (APdeBA) which endorses its activities and guarantees its identity. IPA's requirements for analytic training (didactic analysis, supervisions and seminars) have been fully preserved in this new context. Finally, some of the advantages and disadvantages of including analytic training into an academic environment are listed. [source]


Economic voting: The effect of political context, volatility and turnout on voters' assignment of responsibility

EUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 5 2004
ÅSA BENGTSSON
Voters' assignment of responsibility for the state of the national economy is assumed to vary according to the context of the election. Building on previous research, the importance of the political context , clarity of responsibility and availability of alternatives , is analysed. The study also breaks new ground by introducing two new contexts of importance: volatility, seen from a systemic perspective, and the trend in turnout. The contextual hypothesis is confirmed. The universal economic effect as such is very weak indeed. However, given a favourable political and institutional environment (clear responsibility structure and availability of alternatives), an economic effect appears. Tests including the new contexts created on the basis of behavioural patterns in the electorate (system volatility and turnout trend) identify elections where the economic effects are even stronger. [source]


Reading and Writing the Stasi File: on the Uses and Abuses of The File as (auto)biography

GERMAN LIFE AND LETTERS, Issue 4 2003
Alison Lewis
The opening of the Stasi files in 1992, made possible by the Stasi Documents Legislation, was an important symbolic act of reconciliation between victims and perpetrators. For victims, reading their file provided a means of re-appropriating stolen aspects of their lives and rewriting their life histories. This article argues that the Stasi file itself can be viewed as a form of hostile biography, authored by an oppressive state apparatus, that constituted in GDR times an all-powerful written ,technology of power'. The analogy of secret police files to literary genres enables us to pose a number of questions about the current uses to which the files are being put by victims and perpetrators. Are victims and perpetrators making similar use of their Stasi file in the writing of their autobiographies? What happens when the secret police file is removed from its original bureaucratic context and ,regime of truth' and starts to circulate as literary artefact in new contexts, for instance, as part of victims' and perpetrators' autobiographies? How is the value of the Stasi file now being judged? Is the file being used principally in the services of truth and reconciliation, as originally intended in the legislation, or does it now circulate in ,regimes of value' that place a higher premium on accounts of perpetrators, as can be witnessed in the publication of the fictitious ,autobiography' of the notorious secret police informer, Sascha Anderson? [source]


Contested Mythologies: The Architectural Deconstruction of a Totalitarian Culture

JOURNAL OF ARCHITECTURAL EDUCATION, Issue 4 2001
Roann Barris
One question facing post-totalitarian countries such as Romania would appear to be the extent to which the creation of a political theocracy is rooted in place or in person, and the extent to which revision of the built environment can deconstruct this. This "political spirituality" may, perhaps, be better described as a network of mythologies, some of which are contemporary myths and memories created to explain or assimilate contemporary events and some of which are more archaic or folkloric but reattached to new contexts of meaning. The 1996 architectural competition, the Bucuresti 2000, in its attempt to reframe the urban and architectural interventions imposed by Ceausescu before his deposition, illuminates the complexity of this goal and the ways in which the entire competition process was informed by the histories and mythologies of Bucharest,in particular, the reality and mythology of trauma. [source]


Learning the Dynamic Processes of Color and Light in Interior Design

JOURNAL OF INTERIOR DESIGN, Issue 2 2009
Tiiu Poldma Ph.D.
ABSTRACT Interior environments and their design are profoundly influenced by how designers integrate color and light with form and space. In our increasingly global world, new lighting technologies are changing our perception of color and light and subsequently our interrelationships with one another and with interior space. This alters the choices that we have as designers when we make both color and light decisions. Traditional light and color theories are being challenged with new lighting approaches that are complex, dynamic, and that are changing people's immediate experiences within spaces. Currently, new light technologies alter our perceptual relationships with people and forms, as light, its spectral color, and the forms its affects are more interactive and modulated in real time. Usually, in interior design coursework, students learn about color and light as static theories that they are then asked to apply within the interior design of spaces in subsequent design studios. Through a presentation and examination of the course "Color and Light in Interior Design," this paper proposes considering integrating color and light theories with new contexts of dynamic, integrated human experiences of color and light in interior space. Students acquire learning experiences that integrate theory and practice by understanding the complex interrelationships of light, color, and objects in interior spaces as interactive, and by exploring design concepts in actual environments as a laboratory where they can test theories and their own ideas. The course structure is described and the theories underlying the course goals are explored. Color and light theories are considered in the context of emerging technologies and how phenomenological approaches affect our perceptions and experiences in spaces. Student examples of two of the four course projects are presented as these put theories into practice. The discussion shows that light and color theory, when explored in this way, stimulates both comprehensive and creative responses that integrate new technology with aesthetic theory and functional aspects of well-designed light/color solutions. The integrating of practice into theory stimulates reflective thinking and an understanding of situated contexts in interior design problem solving. The course develops emerging necessities of understanding dynamic color/light concepts that contribute to broadening interior design applied knowledge. [source]


Rhotacization and the ,Beijing Smooth Operator': The social meaning of a linguistic variable1

JOURNAL OF SOCIOLINGUISTICS, Issue 2 2008
Qing Zhang
Recent sociolinguistic studies on style have focused much attention on the construction of social meaning in situated discursive practices. Despite a general recognition that the linguistic resources used are often already imbued with social meanings, little research has been done on what these meanings may be. Focusing on rhotacization, a sociolinguistic variable in Beijing Mandarin, this article explores its imbued social meanings and sociocultural associations. I demonstrate that rhotacization takes on semiotic saliency through co-occurrence with key Beijing cultural terms and frequent use in written representations of authentic Beijing-ness. Furthermore, this feature is associated with the ,Beijing Smooth Operator,' a salient male local character type, and is ideologically construed as reflecting its characterological attributes. The findings of this study shed light on the meaning potential of a linguistic variable, rhotacization in this case, which can enhance understanding of the possibilities and constraints for its use and meaning in new contexts. [source]


Risk news in the world of Internet newsgroups

JOURNAL OF SOCIOLINGUISTICS, Issue 1 2001
Kay Richardson
The coming of the Internet has provided those who are able to benefit from it new ways of giving and seeking information. These new contexts of communication include newsgroups, very much a text-based form of interaction with little visual enhancement. In the new era of ,risk society' (Beck 1992) people make use of newsgroups to talk about the risks which now confront the world, in their pursuit of trustworthy information and informants. Using the affair of Mad Cow Disease (BSE), with particular reference to the crisis in 1996, this article explores the dynamics of news exchange via the newsgroups as a process which is Interactive, International, Interested and Intertextual. These characteristics result in a form of discourse through which participants engage in the interpersonal social construction of risk. The credibility of the proposition that BSE poses a health risk to humans is the focus of their discussions: they are concerned with the nature of the evidence for that proposition and with the reliability of the sources responsible for endorsing it. [source]


Discrepant Feeling Rules and Unscripted Emotion Work: Women Coping With Termination for Fetal Anomaly

AMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 4 2009
Judith L. M. McCoyd PhD
The sociology of emotion is rapidly evolving and has implications for medical settings. Advancing medical technologies create new contexts for decision-making and emotional reaction that are framed by "feeling rules." Feeling rules guide not only behavior, but also how one believes one should feel, thereby causing one to attempt to bring one's authentic feelings into line with perceived feeling rules. Using qualitative data, the theoretical existence of feeling rules in pregnancy and prenatal testing is confirmed. Further examination extends this analysis: at times of technological development feeling rules are often discrepant, leaving patients with unscripted emotion work. Data from a study of women who interrupted anomalous pregnancies indicate that feeling rules are unclear when competing feeling rules are operating during times of societal and technological change. Because much of this occurs below the level of consciousness, medical and psychological services providers need to be aware of potential discrepancies in feeling rules and assist patients in identifying the salient feeling rules. Patients' struggles ease when they can recognize the discrepancies and assess their implications for decision-making and emotional response. [source]


Is ,new' anti-Semitism really ,new'?,

PSYCHOTHERAPY AND POLITICS INTERNATIONAL, Issue 2 2006
George Halasz
Abstract The paper considers whether the ,new' anti-Semitism identified by, for example, Bauer, Pipes and Sacks is in fact a new phenomenon. It considers several key moments in the history of anti-Semitism, together with a series of meetings facilitated by Volkan between psychotherapists affected by the Holocaust. The conclusion is that the ,new' manifestations are ,old' processes reactivated in new contexts. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Coherence versus fragmentation in the development of the concept of force

COGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 6 2004
Andrea A. DiSessa
Abstract This article aims to contribute to the literature on conceptual change by engaging in direct theoretical and empirical comparison of contrasting views. We take up the question of whether naïve physical ideas are coherent or fragmented, building specifically on recent work supporting claims of coherence with respect to the concept of force by Ioannides and Vosniadou [Ioannides, C., & Vosniadou, C. (2002). The changing meanings of force. Cognitive Science Quarterly 2, 5,61]. We first engage in a theoretical inquiry on the nature of coherence and fragmentation, concluding that these terms are not well-defined, and proposing a set of issues that may be better specified. The issues have to do with contextuality, which concerns the range of contexts in which a concept (meaning, model, theory) applies, and relational structure, which is how elements of a concept (meaning, model, or theory) relate to one another. We further propose an enhanced theoretical and empirical accountability for what and how much one needs to say in order to have specified a concept. Vague specification of the meaning of a concept can lead to many kinds of difficulties. Empirically, we conducted two studies. A study patterned closely on Ioannides and Vosniadou's work (which we call a quasi-replication) failed to confirm their operationalizations of "coherent." An extension study, based on a more encompassing specification of the concept of force, showed three kinds of results: (1) Subjects attend to more features than mentioned by Ioannides and Vosniadou, and they changed answers systematically based on these features; (2)We found substantial differences in the way subjects thought about the new contexts we asked about, which undermined claims for homogeneity within even the category of subjects (having one particular meaning associated with "force") that best survived our quasi-replication; (3) We found much reasoning of subjects about forces that cannot be accounted for by the meanings specified by Ioannides and Vosniadou. All in all, we argue that, with a greater attention to contextuality and with an appropriately broad specification of the meaning of a concept like force, Ioannides and Vosniadou's claims to have demonstrated coherence seem strongly undermined. Students' ideas are not random and chaotic; but neither are they simply described and strongly systematic. [source]