bluuebunny/crossref_metadata_2025 huggingface dataset:
Screen-Shifting: Consumption, ‘Riskless Risks’ and the Changing Geographies of Cinema
Authors: Hubbard Phil
Published: August 2002

It is widely acknowledged that the geography of film exhibition in the urban West has changed significantly as ‘traditional’ town centre and suburban cinemas have been supplemented, and in some cases supplanted, by multiplex cinemas in out-of-town locations. In this paper I explore the reasons for this shift, using case-study data from Leicester (United Kingdom) to explore the forms of sociality played out in different sites of film exhibition. These data suggest that multiplex cinemas are frequented predominantly by consumer groups seeking an ‘exopolitan’ leisure experience that is predictable and riskless. In contrast, it appears there are many who continue to frequent city-centre and suburban cinemas because they prefer the less predictable ambience of ‘urban’ leisure. The coexistence of these different forms of cinemagoing is discussed in relation to unfolding debates about the postmodern city—a city that accommodates consumers' predilection for ‘riskless risks’ by holding different forms of sociality apart.
Opportunities for Transport Mode Change: An Exploration of a Disaggregated Approach
Authors: Dijst Martin , de Jong Tom , van Eck Jan Ritsema
Published: August 2002

Research into the effects of spatial configuration on the use of transport modes has to date dominantly been based on analyses of actual travel behaviour or prediction of future transport mode choices. However, in this research it is not made clear what choice opportunities were available for travel behaviour of the various population categories, given their desired activities and time–space opportunities. The authors describe a time–space theoretical and methodological framework based on the concept of action spaces, within which the choice opportunities of different types of households of various areas can be analysed. On the basis of a pilot study among the residents of a suburban neighbourhood in a Netherlands new town, the time–space opportunities they have to use alternative transport modes other than the car are brought into the frame. It is shown that residents have more time–space opportunities to make use of existing environmentally friendly, transport modes than had been expected. The possibilities differ between types of action spaces and types of households. Some implications for policymaking are discussed. The authors state that policymakers should be more sensitive to interpersonal differences in accessibility.
Postwar Trends, Land-Cover Changes, and Patterns of Suburban Development: The Case of Greater Seattle
Authors: Stanilov Kiril
Published: August 2002

A primary objective of this research is to enhance our understanding of the dynamic and complex patterns of suburban growth and to explore the spatial characteristics of land-use distribution during the last few decades of metropolitan expansion. Traditionally, studies of distribution of activities within metropolitan regions have been carried out on vastly aggregated spatial units of analysis based on census geography. Recent innovations in computer technology and software developoment in the field of geographic information systems have allowed much more comprehensive, high-level resolution studies to be undertaken. The study, presented in this paper, is an attempt to develop a fine-grained inspection of the evolution of suburban growth patterns through a detailed documentation of land-use-cover changes in the suburban periphery of Seattle.
Gated Housing Estates in the Arab World: Case Studies in Lebanon and Riyadh, Saudi Arabia
Authors: Glasze Georg , Alkhayyal Abdallah
Published: August 2002

The authors analyze the cultural, economic, and political background of new gated housing estates in the Arab world with the aid of case studies in Lebanon and Riyadh. Their question is to what extent these developments represent a reappearance of the fragmented settlement patterns in many of the old towns. On the one hand, new compounds of several villas and common facilities housing extended families in Riyadh may be interpreted as a revival of certain sociospatial settings in the old town, in which extended families often shared a common courtyard. The compounds for Western foreigners in Saudi Arabia follow the principle of spatial seclusion of social groups with different cultural and religious backgrounds—a principle of the sociospatial organization of many old towns in the Arab world. The emergence of gated housing estates in Lebanon, on the other hand, has obvious and specific sociopolitical origins in the 20th century. The failure of public regimentation and provision created a gap, which was partially filled by the private sector. For their mostly wealthy clientele, gated housing estates offer private small-scale solutions to nationwide problems.
Public Participation and the Art of Governance
Authors: Pløger John
Published: August 2002

Theories about communicative planning have forcefully emphasised how language and modes of communication play a key role in shaping planning practice, public dialogues, policymaking, and processes of collaboration. These days, however, discussions on planning seem to reestablish an old philosophical confrontation between Jürgen Habermas's plea for a discoursive ethic and Michel Foucault's thesis of the omnipresence of discoursive powers. Some—mostly overlooked—central themes to this controversy are the epistemological and ontological conditions of Habermas's theory of communicative action. Furthermore, theories of communicative and collaborative planning are criticised because they do not deal with questions on government and governmentality when the power of institutional discourses and the planning of legal decisional structures are discussed. In this paper, I will exemplify the controversy between the Habermasian (the ethics of participation and democratic communication) and the Foucaultian (the art of governance) planning theories, by comparing public participation in Norway with experiments on citizen involvement in Denmark.
Argumentation Maps: GIS-Based Discussion Support for On-Line Planning
Authors: Rinner Claus
Published: August 2002

Information technology plays a growing role in planning procedures. A procedure step which has not been supported by specific computer tools up to now, is asynchronous discussions. Such discussions can occur in public participation as well as between planners during plan design. In this paper I introduce argumentation models as a way of structuring debates, and review existing tools for recording argumentation. A limited number of tools support design-related or map-related discussions. Their short-comings for analyzing geographically referenced arguments are discussed. Finally, the concept of ‘argumentation maps’ is described, which combine the strengths of rigorous argumentation modeling and detailed geographic location to support map-based discussions in on-line planning.
Institutional Barriers to Sustainable Construction
Authors: van Bueren Ellen M , Priemus Hugo
Published: August 2002

Sustainable construction has developed in the past few decades in the Netherlands to a mature subject of policy, research, and innovation. In the technological field the opportunities for sustainable construction seem to be unlimited. In practice, in the Netherlands, measures to give concrete form to sustainable construction are only scantily applied. The suspicion arises that it is not technical factors but institutional factors that underlie the fact that as yet sustainable construction has failed to force a definitive breakthrough. The authors review to what extent institutions that influence the decisionmaking of players in the building sector regarding whether or not to apply sustainable construction have hindered improvement in sustainable construction.
Nature, Home, and Scenery: The Official Spatialities of Swedish National Parks
Authors: Mels Tom
Published: August 2002

In this paper I explore past and present ‘official’ spatialities of the Swedish national parks, and trace ways in which rhetorical mediation secures the naturalization and nationalization of park spaces. With the help of Lefebvre's writings on space, I argue that three interrelated spatialities constitute the abstract space of Swedish national parks: empty, organic, and optical space. Empty space embodies understandings of national parks as ‘pure’ nature, external to (modern) society. Organic space circumscribes modes of representation that link nature to conceptions of ‘Swedishness’. Through a multimedia dialectic of images, texts, and maps—the optical space of visual immediacy and ‘proof’—these spatialities are maintained and policed.
Environmental Policy, Land Rights, and Conflict: Rethinking Community Natural Resource Management Programs in Burkina Faso
Authors: Gray Leslie C
Published: August 2002

In this paper I will examine the effects of the implementation of the Gestion des Terroirs approach in several villages in the cotton-growing region of southwestern Burkina Faso, an area of both extensive immigration and fast-paced socioeconomic change. Efforts to restructure land-tenure relations have failed, despite the rhetoric of participatory development, because projects misunderstand the nature of changing land rights, agricultural practices, and village social relations. Failures of efforts to zone land have been exacerbated because land has become a major site of conflict. Population growth and agricultural growth have led to land shortages, intensified competition, and overt conflict. Efforts to restructure landholding by using participatory development methods have had unintended consequences as individuals and groups manipulate meanings and representations about rights to land and land-management strategies in order to lay claim to land. On the one hand some local farmers are attempting to expel migrant farmers from land by invoking notions of who is and who is not using environmentally sound management practices. Migrant farmers, on the other hand, are fearful of leaving land fallow because they fear that the project or their local hosts will take it away from them. Both of these outcomes have increased tension among ethnic and generational groups and fostered mistrust of the motivations of environmental projects. Instead of homogeneous cooperative entities, villages are often based on conflict and competition. Projects, therefore, should focus on conflict resolution and reconciliation when attempting to restructure how natural resources are allocated.
The Seductions of Resistance: Power, Politics, and a Performative Style of Systems
Authors: Rose Mitch
Published: August 2002

Studies of resistance challenge overly structural conceptions of social systems by emphasizing the various forms of creative practice operating within hegemonic space. Yet, by illustrating the different ways that agents respond to a dominant system, resistance theory inadvertently establishes that system as a preestablished entity. Thus, although resistance theory endeavours to recognize the ongoing deconstructs of systems, it simultaneously reifies the system as primary. In response, I argue that this problem is not indicative of a flaw in resistance theory per se, but rather of a flaw in the conception of systems it operates with. Drawing upon Butler's work on performativity, I develop an alternative theory of systems that accounts for social coherence and stratified relations of power through creative forms of social practice alone. Rather than depending on sociostructural concepts such as ideology, hegemony, and normative space, a performative theory of systems situates creative social practice as the engine of social coherence. In this framework theories of resistance are redundant because creative practices are the rule of systems rather than a challenge to their stability.
Postcards and Frontier Mythologies: Sustaining Views of the Kimberley as Timeless
Authors: Waitt Gordon , Head Lesley
Published: August 2002

In this paper we examine the role of postcards in disseminating and circulating Australian frontier myths. Cultural geographers have generally overlooked this mode of tourist communication. Yet, the postcard is an example par excellence of both a genre of popular art and an ephemeral cultural artefact. The ritual practice of selecting, writing, and sending a postcard is explored within the themes of souvenir, testimony, and anticipation. A report is provided of methods designed to reveal how individual tourists interpret these postcards as semiotic texts. Results suggest that postcards seem to perpetuate, almost unchallenged, experiences associated with Australian frontier mythologies. The Kimberley is experienced as a remnant of a former pristine environment and a place uninhabited or, at best, inhabited by ‘primitive’ people. This version of the Kimberley relies upon many of the categorical binaries between society and nature; human and animal; civilised and wild. The silences and priorities created by such textual imagery in the public geographical imaginary are argued to be far from trivial in a place subject to native land claims and proposed extensions to irrigation schemes.
The ‘Place’ of Land in Japan's Postwar Development, and the Dynamic of the 1980s Real-Estate ‘Bubble’ and 1990s Banking Crisis
Authors: Kerr Derek
Published: August 2002

In this paper I seek to unfold the place of landed property within Japan's postwar uneven development and the way in which this found expression in the 1980s real-estate ‘bubble’ and subsequent 1990s banking crisis. I argue that landed property was both internal to and constitutive of the social relations that marked the specificity of Japan's postwar capitalism. As a national state within the accumulation of global capital, however, Japan's specificity only existed as ‘difference-in-unity’. Furthermore, I suggest that the 1980s real-estate ‘bubble’ and 1990s banking crisis were specific and culminating expressions of changes within the form of those social relations, as mediated by Japan's changing position within the process of global uneven development. Important in this respect was the way in which credit, fictitious capital, and spatial restructuring became precarious expressions of attempts to achieve a temporal and spatial displacement of crisis.
Boundary Making and Regional Identities in a Globalized Environment: Reordering the Nariva Swamp, Trinidad
Authors: Sletto Bjørn
Published: August 2002

The recent work in critical geopolitics problematizes the notion of boundaries and interrogates the narratives, ideologies, and institutions that inform processes of boundary making, or ‘reborderings’. From the perspective of critical geopolitics, boundary making for conservation purposes is understood as an act of power embedded within a discourse of environmental geopolitics. Through reborderings, environmental geopolitics thus reflects and informs everyday practices and relations of power between local, state, and international actors. In this paper I illustrate a process of rebordering in Trinidad, the West Indies, in which local, state, and international actors engaged in a contest to define conservation boundaries and produce bounded identities within the Nariva Swamp. Rebordering in the Nariva Swamp reflected and influenced state and local practices in complex ways, altered relations of power on multiple levels, and led to the production of a bounded space that is simultaneously local and global.
Framing Corkerhill: Identity, Agency, and Injustice
Authors: Robinson Andy
Published: August 2002

The author seeks to examine the roots of community mobilisation against contested developments. By utilising the concept of collective action frames he attempts to demonstrate that ideas of injustice, identity, and agency are crucial in explaining the development of community opposition. Furthermore, he shows that spatial concepts of exclusion, segregation, and isolation are central to the development of these elements of opposition and therefore important explanatory factors when accounting for grass-roots collective action.
New Body-Geographies: The Embodied Spaces of Health and Medical Information on the Internet
Authors: Parr Hester
Published: August 2002

This paper deals with the rise of health and medical information on the Internet and considers the implications of this for a sociocultural geography of the body. The key purpose is to document how this information is communicated, consumed, and embodied, and also to evaluate how ‘healthy’ and ‘ill’ bodies constitute important geographies which are negotiated and contested in virtual space. There are two clear foci in the paper. First, using Foucauldian understandings of medicalisation, the notion of a ‘fourth spatialisation’ of the medical gaze is evaluated in the context of the Internet as a new geography of health promotion which enables human subjects to ‘self-diagnose’ and to ‘discipline’ their bodies. Second, this argument is complicated by the use of empirical examples gathered from MS chat rooms, places in which communities of people gather to discuss and to contest medical knowledges which surround the ‘ill’ body. The paper concludes with speculation on research pathways for a ‘new medical geography’.
Obtaining the ‘Due Observance of Justice’: The Geographies of Colonial Humanitarianism
Authors: Lester Alan
Published: August 2002

Within the context of contemporary discussion over geography and developmental ethics, this paper examines part of the genealogy of a modern British sense of responsibility for the plight of distant strangers. The frame of reference for this sense, known as humanitarianism, was first cast overseas through debates over the slave trade in the late 18th century, and its remit was further extended as a result of the contested processes of colonial settlement in the 1820s and 1830s. This geographically expansive discourse is analysed through a study of two exemplary statements of humane intervention: the Aborigines Committee (1835–37), and the military Court of Enquiry into the death of the African Xhosa King Hintsa (1836). Each demonstrated a new-found concern for the fate of colonised individuals. They established that the sufferings of distant others were inextricably connected to the everyday privileges enjoyed by Britons. However, they also formulated prescriptive principles targeted not only at the relief of suffering, but at the moral and material improvement of distant subjects—principles which continue to inform more recent debates over global ethics.
Induction in Variants of White's Effect: Common or Separate Mechanisms?
Authors: Spehar Branka , Clifford Colin W G , Agostini Tiziano
Published: August 2002

In White's display the gray target surrounded more by black than white appears darker than the target of the same physical luminance surrounded more by white than black. Several subsequent studies have shown that this effect occurs only when the luminance of the test regions lies between the minimum and maximum luminance values of the inducing stripes. With targets either lighter or darker than both inducing stripes, the direction of the effect is reversed and the effect is known as the ‘inverted’ White's effect. Views differ on whether the classical and inverted White's effects are mediated by common or separate underlying mechanisms. We varied the aspect ratio of the test and inducing regions in the classical and inverted White's effects. Consistent with previously reported findings, we found that the direction of the classical effect did not depend on the amount of black or white border in immediate contact with the test patch. On the other hand, perceived lightness in the inverted White's effect was affected by such variations, suggesting that induction in classical and inverted White's configurations is governed by different mechanisms. These results confirm the critical importance of the interaction between luminance and geometric relationships in induced brightness.
Cleomedes (C. 1St Century Ad) on the Celestial Illusion, Atmospheric Enlargement, and Size – Distance Invariance
Authors: Ross Helen E
Published: August 2002

Cleomedes (Kleomedes) is a little-known Greek author (c. 1st century AD) who produced what is probably the earliest extant statement of size – distance invariance. He supported the Stoic philosophy and was concerned to discredit the Epicurean position that we perceive objects as having their true size. He explained the celestial illusion (the apparent enlargement of the sun near the horizon) in two ways: partly as a refractive effect of the atmosphere similar to angular enlargement when looking into water; and partly as a linear enlargement due to increased apparent distance in a misty atmosphere. He is the earliest extant author to offer apparent distance as a clear explanation of the celestial illusion. He attributed these views to Posidonius (c. 135–50 BC). His explanations remained at the geometrical level, and he did not speculate on sensory mechanisms.
The Brain May Know More than Cognitive Theory Can Tell Us: A Reply to Ted Parks
Authors: Dresp Birgitta , Spillmann Lothar
Published: August 2002

In reply to Parks' interpretation of Rock's cognitive theory of illusory figures, we maintain our point of view that such a theory has limited heuristic and explanatory power because it fails to predict subjects' responses in psychophysical tasks. As a result, the theoretical framework defended by Parks is not appropriate for suggesting candidate mechanisms of brain – behaviour function that could underly the phenomenal emergence of such figures.
Vertical and Bisection Bias in Active Touch
Authors: Millar Susanna , Al-Attar Zainab
Published: August 2002

We investigated the conditions that underlie the vertical and bisection illusion in touch, in order to understand the basis of their similarity to visual illusions, and the means of reducing the biases in length perception by active touch. Movement, speed, and spatial reference cues were tested. Movements in scanning L-shapes in ipsilateral and contralateral (across the body midline) table-top space produced significant underestimation of the vertical line with the right hand, but not with the left hand. Right-handed scanning of L-shapes showed no significant bias when the vertical line in the figure was aligned to the body midline, suggesting that spatial cues were involved. The vertical line was overestimated in inverted T-shapes, but underestimated in rotated T-shapes, implicating line bisection. Holding scanning latencies constant reduced the vertical error for inverted T-shapes, but could not explain the bisection bias. Sectioning biases were predicted by the location of junctions on sectioned lines, showing that junction points act as misleading anchor cues for movement extents. The illusion was significantly reduced when reference information was added by instructing subjects to relate two-handed scanning of the figure to an external frame and to body-centred cues. It is argued that disparities in spatial reference (anchor) cues for movement extents are involved in vertical and bisection biases in active touch. The hypothesis that length illusions depend on disparities in spatial reference information can also account for the similarity of the tactile to the visual horizontal – vertical illusion.
Role of Chromaticity, Contrast, and Local Orientation Cues in the Perception of Density
Authors: Beaudot William H A , Mullen Kathy T
Published: August 2002

We compared the role of the red–green, blue–yellow, and luminance post-receptoral mechanisms in the perception of density. The task requires the comparison of densities between two stimuli composed of oriented bandpass elements, pseudo-randomly scattered across an area of constant size. The perception of density differences was measured by a temporal 2AFC procedure for all pairs of mechanisms and for four possible densities. We found that stimuli of identical physical densities are not perceived equally: there is a consistent bias in favour of blue-yellow stimuli which are perceived as significantly more dense than red–green and achromatic stimuli. We considered three factors that could have differentially affected the density perception of blue – yellow stimuli: an increase in the perceived size of the individual blue – yellow elements, a perceived contrast difference, and the presence of local orientation cues. We found that the increased perceived density of the blue–yellow stimuli occurred despite the fact that there was no increase in perceived size of the individual elements, and remained despite corrections for the two other factors. We conclude that the significant increase in perceived density for the blue–yellow mechanism is a global effect, associated with a perceived colour ‘melting’ of the elements in the array. Our data were fitted with the occupancy model of Allik and Tuulmets (1991, Perception & Psychophysics49 303–314) and we found that blue–yellow stimuli have a greater ‘occupancy’ than red–green or achromatic stimuli.
Active versus Passive Processing of Biological Motion
Authors: Thornton Ian M , Rensink Ronald A , Shiffrar Maggie
Published: August 2002

Johansson's point-light walker figures remain one of the most powerful and convincing examples of the role that motion can play in the perception of form (Johansson, 1973 Perception & Psychophysics14 201–211; 1975 Scientific American232(6) 76–88). In the current work, we use a dual-task paradigm to explore the role of attention in the processing of such stimuli. In two experiments we find striking differences in the degree to which direction-discrimination performance in point-light walker displays appears to rely on attention. Specifically, we find that performance in displays thought to involve top – down processing, either in time (experiment 1) or space (experiment 2) is adversely affected by dividing attention. In contrast, dividing attention has little effect on performance in displays that allow low-level, bottom – up computations to be carried out. We interpret these results using the active/passive motion distinction introduced by Cavanagh (1991 Spatial Vision5 303–309).
The Temporal Course of Suppression during Binocular Rivalry
Authors: Norman Hideko F , Norman J Farley , Bilotta Joseph
Published: August 2002

Orthogonally oriented sinusoidal luminance gratings were dichoptically presented to the observers' left and right eyes. During the subsequent binocular rivalry, a small target was briefly presented (4AFC) to probe the strength of interocular suppression at various temporal latencies. Both stationary and moving rivalrous patterns were investigated. The purpose of experiment 1 was to compare the temporal characteristics of stationary and motion rivalry (0 and 1.2 deg s−1), while that of experiment 2 was to examine rivalry suppression for higher speeds (2 and 4 deg s−1). In all cases, it was found that the strength of suppression remained essentially constant throughout a single phase of binocular rivalry. The results of the investigation also revealed that moving rivalrous patterns lead to greater magnitudes of interocular suppression than static patterns. Despite these differences in the strength of suppression, the results of both experiments show that the temporal characteristics of motion and static rivalry are essentially identical.
A Double Neon Colour Illusion
Authors: van Lier Rob
Published: August 2002

A new visual illusion is presented. When two neon-coloured illusory bands overlap each other, the filling-in at the region of overlap is perceived as different from those of the overlapping bands, resulting in an additional illusory shape at the region of overlap. An experiment with ten naive participants was performed to measure the illusory percept. The results show that illusory surfaces may interact with each other, and, to a certain extent, create new illusory percepts.
Is There a Linear or a Nonlinear Relationship between Rotation and Configural Processing of Faces?
Authors: Collishaw Stephan M , Hole Graham J
Published: August 2002

Research suggests that inverted faces are harder to recognise than upright faces because of a disruption in processing their configural properties. Reasons for this difficulty were explored by investigating people's ability to identify faces at intermediate angles of rotation. Participants were asked to discriminate blurred famous and unfamiliar faces presented at nine angles. Blurred faces were used to minimise featural processing strategies, and to assess the effects of rotation that are specific to configural processing. The results indicate a linear relationship between angle of rotation and recognition accuracy. It appears that configural processing becomes gradually more disrupted the further a face is oriented away from the upright. The implications of these findings for competing explanations of the face-inversion effect are discussed.
The Eye as an Optical Instrument: From Camera Obscura to Helmholtz's Perspective
Authors: Wade Nicholas J , Finger Stanley
Published: August 2002

The era of modern vision research can be thought of as beginning in the seventeenth century with Johannes Kepler's understanding of the optics of the camera obscura with a lens and its relation to the eye. During the nineteenth century, Helmholtz used “The eye as an optical instrument” as the title for one of his Popular Lectures, and such a conception of the eye is now accepted as a fundamental feature of visual science. In analysing the optics of the eye, Helmholtz constructed some novel optical instruments for studying the eye. The development of optometers, ophthalmometers, and ophthalmoscopes is presented historically, with emphasis on how these instruments and camera analogies helped scientists to understand the functions of the eye, especially the enigma of accommodation.
Selective Attention to Stimulus Features Modulates Interocular Suppression
Authors: Sasaki Hiroyuki , Gyoba Jiro
Published: August 2002

Psychological and neurophysiological studies have shown that attention modulates various sorts of perceptual processing. Here, we report that attention affects the perceptual dominance of binocular rivalry. Experiments using a dichoptic masking paradigm revealed that when an observer was attending to one of the two orientations of the elements of a monocular texture, a texture briefly presented to the opposite eye suppressed the perception of the elements with the attended orientation, while the elements with the orientation which was ignored sustained their dominance. Moreover, subsequent experiments indicated that the suppression depended on the orientation of the texture elements constituting the mask, but was independent of their locations. These results suggest that attention to specific features modulates interocular suppression in a mode which is different from that found in a previous study [Ooi and He, 1999 Perception28 551–574].
Motion versus Position in the Perception of Head-Centred Movement
Authors: Freeman Tom C A , Sumnall Jane H
Published: August 2002

Observers can recover motion with respect to the head during an eye movement by comparing signals encoding retinal motion and the velocity of pursuit. Evidently there is a mismatch between these signals because perceived head-centred motion is not always veridical. One example is the Filehne illusion, in which a stationary object appears to move in the opposite direction to pursuit. Like the motion aftereffect, the phenomenal experience of the Filehne illusion is one in which the stimulus moves but does not seem to go anywhere. This raises problems when measuring the illusion by motion nulling because the more traditional technique confounds perceived motion with changes in perceived position. We devised a new nulling technique using global-motion stimuli that degraded familiar position cues but preserved cues to motion. Stimuli consisted of random-dot patterns comprising signal and noise dots that moved at the same retinal ‘base’ speed. Noise moved in random directions. In an eye-stationary speed-matching experiment we found noise slowed perceived retinal speed as ‘coherence strength’ (ie percentage of signal) was reduced. The effect occurred over the two-octave range of base speeds studied and well above direction threshold. When the same stimuli were combined with pursuit, observers were able to null the Filehne illusion by adjusting coherence. A power law relating coherence to retinal base speed fit the data well with a negative exponent. Eye-movement recordings showed that pursuit was quite accurate. We then tested the hypothesis that the stimuli found at the null-points appeared to move at the same retinal speed. Two observers supported the hypothesis, a third partially, and a fourth showed a small linear trend. In addition, the retinal speed found by the traditional Filehne technique was similar to the matches obtained with the global-motion stimuli. The results provide support for the idea that speed is the critical cue in head-centred motion perception.
Global Interference: The Effect of Exposure Duration That is Substituted for Spatial Frequency
Authors: Hibi Yuko , Takeda Yuji , Yagi Akihiro
Published: August 2002

In this study, participants were required to identify hierarchically structured patterns that appeared at either global or local level. Paquet and Merikle (1984 Canadian Journal of Psychology381 45–53) showed that global interference is affected by exposure duration in the processing of a hierarchical structure. They showed that only global-to-local interference occurred at short exposure durations. In contrast, global-to-local as well as local-to-global interference was observed at long exposure durations. They suggested that the effect of exposure duration with global interference depends on the high-spatial-frequency versus low-spatial-frequency channel. In the present study, exposure duration (short or long) was varied randomly from trial to trial (experiment 1), or held constant (experiment 2). In experiment 1, global-to-local interference occurred at both short and long exposure durations, even though the same physical properties existed as in experiment 2. In experiment 2, both global-to-local and local-to-global interference occurred at only long exposure durations, in line with the results reported by Paquet and Merikle. This suggests that the effect of exposure duration on global interference is explained not only by spatial-frequency channels, but also by attentional shift.
A Planar and a Volumetric Test for Stereoanomaly
Authors: van Ee Raymond , Richards Whitman
Published: August 2002

Stereoanomaly is the failure to see differences in depth when the viewer is presented with stimuli having different magnitudes of stereoscopic disparity. In the absence of eye movements, everyone suffers from stereoanomaly for extremely large disparities. Typically, such disparities are seen at the same depth as monocular stimuli. However, about 30% of the population exhibit some form of stereoanomaly even for very small disparities, provided eye movements are avoided. In some cases, the sign of the disparity will be confused, and the perceived depth will be incorrectly seen as ‘behind’ rather than ‘in front of’ the fixation point, for example. Because anomalies provide useful information about perceptual mechanisms, tests that measure and quantify the extent of a blindness are important investigative tools for research. Here we offer two easy-to-administer tests for stereoanomaly. The first test is based on depth judgments of two bars relative to a fixation point. The second test involves judgments of volumetric stimuli, seen stereoscopically. In each case, subjects indicate depth by setting a rectangle (with fixed base) to match the perceived depth. Although both tests are correlated, some differences in stereo processing are seen, depending upon whether or not the stimuli are presented near the point of fixation.
Path Integration from Optic Flow and Body Senses in a Homing Task
Authors: Kearns Melissa J , Warren William H , Duchon Andrew P , Tarr Michael J
Published: August 2002

We examined the roles of information from optic flow and body senses (eg vestibular and proprioceptive information) for path integration, using a triangle completion task in a virtual environment. In two experiments, the contribution of optic flow was isolated by using a joystick control. Five circular arenas were used for testing: (B) both floor and wall texture; (F) floor texture only, reducing information for rotation; (W) wall texture only, reducing information for translation; (N) a no texture control condition; and (P) an array of posts. The results indicate that humans can use optic flow for path integration and are differentially influenced by rotational and translational flow. In a third experiment, participants actively walked in arenas B, F, and N, so body senses were also available. Performance shifted from a pattern of underturning to overturning and exhibited decreased variability, similar responses with and without optic flow, and no attrition. The results indicate that path integration can be performed by integrating optic flow, but when information from body senses is available it appears to dominate.
Oil concentration and composition of olives during fruit maturation in south-western New South Wales
Authors: Ayton J. , Mailer R. J. , Robards K. , Orchard B. , Vonarx M.
Published: August 2002

This paper reports on an observational study of the oil and moisture content,
and fatty acid profile, of olives (Olea europaea) for 15
tree groupings with groups consisting of trees with similar DNA patterns.
Observations were taken at 2 sites (Wagga Wagga and Yanco) in south-western
New South Wales, over 2 seasons. These sites represent the largest gene pool
of developed olive trees in Australia. Differences in oil and moisture content
were identified at both the Wagga Wagga and Yanco sites. At the former site,
group 12 (˜cv. Tarascoa) had the highest oil content at full colour
development in both 1998 and 1999 (50.1 and 45.5% dry weight,
respectively) while at Yanco, group 15 (˜cv. Verdale) had the
highest oil content in both years with 51.6 and 45.3%,
respectively. The fatty acid profile was shown to be highly dependent upon
tree group (i.e. cultivar), and with further study may be used as a method for
discriminating among cultivars.
The pattern of development of oil, moisture and fatty acids (palmitic,
palmitoleic, stearic, oleic, linoleic and linolenic acids) is also detailed
for 4 trees in the Wagga Wagga grove over the ripening season in 1998 and
1999. For these trees, oil content (dry weight basis) increased rapidly in the
first 15 weeks (January–April) while moisture declined except for a
small increase at around 10 weeks (mid-March). Fatty acid development showed
similar trends between the trees over the length of the study.
A Low-Cost Smart Measurement System for Resistive (Bridge) or Capacitive Sensors
Authors: Wang Guijie , Meijer Gerard C. M. , van der Goes Frank M. L. , Li Xiujun , Kerkvliet Harry M. M.
Published: August 2002

A low-cost smart measurement system for resistive (bridge) or capacitive sensors is presented. The measurement system consists of three main parts: the sensor element, a universal transducer interface (UTI) and a microcontroller. The Universal Transducer Interface (UTI) is equipped with front-ends for many types of resistive (bridge) and capacitive sensors. It is a sensor-signal-to-time converter, based on a period-modulated oscillator, which generates a microcontroller-compatible output signal. The microcontroller performs data acquisition of the output signals from the UTI, controls the operating conditions and communicates with a personal computer. Continuous auto-calibration is applied to eliminate the influences of offset and gain errors. According to the experimental results the accuracy and resolution amounts to 13 bits and 16 bits, respectively, for a measurement time of about 100 ms.
Modeling the Influence of pH, Temperature and Culture Medium Composition on the Kinetics of Growth and Cysteine Proteinase Production by Micrococcus sp. INIA 528 in Batch Culture
Authors: Mohedano A. F. , Casas J. A. , Fernández J. , García-Ochoa F. , Nuñez M.
Published: August 2002

Kinetics of biomass and cysteine proteinase formation during growth of Micrococcussp. INIA 528 in batch cultivation were studied. Modeling of cultivation data was carried out using an unstructured model. The logistic equation was found to be adequate to describe microbial growth. Production of cysteine proteinase was described by means of an equation including biomass and substrate concentrations. An overall model based on an equation of substrate consumption dependent on biomass formation and proteinase production was postulated. The kinetic parameters (specific growth rate, maximum biomass, proteinase production rate and proteinase formation yield) were obtained taking into account the influence of pH (6.0–8.0), temperature (28–41 ºC) and the addition of different supplements to the basal culture medium [yeast extract, MgSO 4,glucose, K2HPO4 and (NH4)2SO4]. Kinetic parameters were calculated by fitting experimental data by a nonlinear technique using the algorithm of Marquardt coupled to a fourth-order Runge-Kutta subroutine.
Control of Transient Thermoelastic Displacement in a Piezoelectric Based Intelligent Plate
Authors: Ashida Fumihiro , Noda Naotake
Published: August 2002

The present paper deals with an intelligent solid state actuator which can control a distribution of thermoelastic displacement at submicron order, in the case where unknown transient heating temperature acts on the actuator. The intelligent actuator consists of an isotropic structural layer onto which two piezoceramic layers of crystal class 6 mm are perfectly bonded. First, by analyzing an inverse problem of transient piezothermoelasticity, the unknown heating temperature acting on the structural layer is inferred from the electric potential induced in the middle piezoceramic layer. Next, analysis of a control problem leads to a transient electric potential applied to the top piezoceramic layer which gives the desired elastic displacement distribution on the free surface of the structural layer. Finally, numerical results are illustrated graphically.
Photolithographic Synthesis of Intelligent Microgels
Authors: Ito Yoshihiro
Published: August 2002

Hydrogels having microscopic structures were synthesized by a photolithographic method. First a photoreactive pH or thermo-sensitive polymer was synthesized by chemical coupling of poly(acrylic acid) and poly(N-isopropylacrylamide-co-acrylic acid) with azidoaniline. Sub-sequently, the polymer was coated on a polystyrene plate or a glass plate and the coated plate was photo-irradiated through photomasks having prescribed patterns. pH or thermo-responsive microgels whose structures corresponded to the photomask patterns were constructed. They rapidly swelled and contracted by changing pH or temperature. The pH or temperature-induced structural change was reversible.
Swelling Properties of Various Polymers Used in Controlled Release Systems
Authors: Vlachou M. , Naseef H. , Efentakis M. , Tarantili P. A. , Andreopoulos A. G.
Published: August 2002

The effect of powder packing and porosity of specimens on the swelling properties of polymeric materials was studied, in various swelling liquids, such as distilled water and 0.1 N hydrochloric acid solution. Capsules, tablets and films of hydroxypropyl methylcellulose, poly(ethylene oxide) and sodium alginate were prepared, and their weight uptake after immersion into the above solutions was recorded as a function of time, in order to assess the swelling process. Measurements of some characteristics of the as-received powders were also performed in an attempt to classify the specimens prepared according to their porosity.

Within the experimental conditions of this work, it was shown that the porosity of polymeric specimens is a dominant factor that controls their swelling behaviour. Increased porosity leads to fast initial rates of weight uptake and high extent of equilibrium swelling. On the other hand, dissolution and possible degradation of polymers susceptible to acid hydrolysis results in some variations from the above mentioned behaviour.

With respect to the application in controlled release systems, theoverall delivery rate from a polymeric specimen is expected to be a function of both swelling and disintegration characteristics of a specimen, and therefore, the weight uptake can be considered a measure of the release only in the case of polymers with low water solubility and increased stability to hydrolysis.
Significant Toxicities Associated with Antiretroviral Therapy
Authors: Kanmaz Tina J. , Lee Nancy J.
Published: August 2002

Use of at least three potent antiretroviral agents has become the standard of care in the management of HIV infection. The potential toxicities associated with highly active antiretroviral therapy (HAART) however, may limit a patient’s ability to adhere to and tolerate these agents. Although a comprehensive discussion of all toxicities associated with HAART is beyond the scope of this article, selected short-term and long-term significant toxicities will be reviewed. Short-term toxicities that will be discussed include abacavir-induced hypersensitivity reactions, efavirenz-associated central nervous system side effects and rash associated with the non-nucleoside reverse transcriptase inhibitors (NNRTIs) and the protease inhibitor (PI) amprenavir. Several long-term toxicities associated with the nucleoside reverse transcriptase inhibitors (NRTIs) are hypothesized to be due to mitochondrial toxicity. These toxicities include myositis and lactic acidosis with hepatic steatosis, pancreatitis and peripheral neuropathy. Some experts also hypothesize that mitochondrial toxicity is responsible for the lipodystrophy syndrome, which includes hyperglycemia, abnormal fat redistribution and dyslipidemia. Finally, indinavir-associated nephrolithiasis, which may present with either short term or long term use will be discussed. This article will provide the practicing pharmacist with a review of these significant toxicities, the implicated agents, incidence, usual clinical presentation, and recommendations for management.
Shape Memory Elements in Bending: Influence of the Shape of their Cross-Section
Authors: Kafka Vratislav , Vokoun David
Published: August 2002

The effect of the shape of the cross-section of a bent prismatic bar on its shape memory recovery moment is investigated. The analysis is based on the mathematical model of the first author (Kafka, 1994a, 1994b, 2001). The area of the cross-section of the bar is assumed to be constant, the shape of the cross-section is varied. The investigated shapes are rectangles with various relations of their sides, and a circular cross-section. It is assumed that the rod is bent above elastic limit and unloaded at room temperature, which results in macroscopic residual stresses giving zero bending moment, and in residual internal variables descriptive of the change of the state of the material. Then, the resulting form is held fixed and temperature of the rod is raised. Due to the increase of temperature there arise recovery stresses resulting in recovery moments. These moments—depending on the shape of the cross-section—are calculated, and in this way the effectiveness of the shape of the cross-section is evaluated. In the case of a rectangular cross-section the effect of the relation of the sides is strongly non-linear, the effect of the circular cross-section is lower by 20% than that of a square cross-section.
Assessment of Metallocene Propylene Polymers for Cast Film Applications
Authors: Lin C. Y. , Chen M. C. , Mehta A. K.
Published: August 2002

The entry of metallocene-based products into polypropylene (pp) cast film is at a stage where their potential in various markets is now being assessed. This study reviews the structural features of some metallocene polymers and reports on resulting potential benefits in cast film applications through their use—and also with their use—in blends with Ziegler-Natta based PP.