Neutron-mapping polymer flow: Scattering, flow visualization, and molecular theory

Flows of complex fluids need to be understood at both macroscopic and molecular scales, because it is the macroscopic response that controls the fluid behavior, but the molecular scale that ultimately gives rise to rheological and solid-state properties. Here the flow field of an entangled polymer melt through an extended contraction, typical of many polymer processes, is imaged optically and by small-angle neutron scattering. The dual-probe technique samples both the macroscopic stress field in the flow and the microscopic configuration of the polymer molecules at selected points. The results are compared with a recent tube model molecular theory of entangled melt flow that is able to calculate both the stress and the single-chain structure factor from first principles. The combined action of the three fundamental entangled processes of reptation, contour length fluctuation, and convective constraint release is essential to account quantitatively for the rich rheological behavior. The multiscale approach unearths a new feature: Orientation at the length scale of the entire chain decays considerably more slowly than at the smaller entanglement length.

Blunted prolactin response to D-fenfluramine in post-stroke major depression

Background: This study investigated whether patients suffering from post-stroke depressive disorder had a similar disturbance in central serotonergic function to that described in non-brain injured depressed patients. Methods: Twenty-three depressed patients (nine major, 14 minor) and 38 non-depressed patients were examined 4-8 weeks post-stroke with a structured interview, rating scales and MRI brain scans. Patients were administered 30 mg D-fenfluramine orally and plasma prolactin and D-fenfluramine concentrations were measured for 6 h post-dose. Results: The prolactin response was significantly blunted in major depression compared to minor depression and non-depressed patients as measured by both delta prolactin and area under the prolactin versus time curve. There was no significant relationship between prolactin response and lesion lateralization or any of the measured clinical characteristics. Limitations: The major limitation of the study is the relatively small number in each depressive group. Conclusions: Patients suffering from major depression in the post-stroke period have a blunted prolactin response to D-fenfluramine. This indicates a serotonergic abnormality consistent with that found in major depression where neurological disease is not present. (C) 2003 Elsevier B.V. All rights reserved.

Movement and motor development in ELBW infants at 1 year is related to cognitive and motor abilities at 4 years

A relationship between motor ability and cognitive performance has been previously reported. This study aimed to investigate the association between movement and cognitive performance at 1 and 4 years corrected age of children born less than 1000 g, and whether developmental testing of movement at 1 year is predictive of cognitive performance at 4 years. Motor development was assessed at both ages using the neurosensory motor developmental assessment (NSMDA) and motor development was classified as normal, or minimal, mild, moderate-severe dysfunction. Cognitive performance was assessed on the Griffith Mental Developmental Scale at 1 year and McCarthy Scales of Children's Abilities at 4 years. Subjects included 198 children of birthweight less than 1000 g. Of these 132 children returned for follow-up at the corrected ages of both 1 and 4 years. The 66 children not included had a slight increase in gestational age, while the mothers were younger and had a lower level of education. A significant association was found between NSMDA group classification at 1 year and cognitive performance at both 1 and 4 years (p

Effects of experimentally-induced anterior knee pain on knee joint position sense in healthy individuals

Purpose. The ability to sense the position of limb segments is a highly specialised proprioceptive function important for control of movement. Abnormal knee proprioception has been found in association with several musculoskeletal pathologies but whether nociceptive Stimulation can produce these proprioceptive changes is unclear. This study evaluated the effect of experimentally induced knee pain on knee joint position sense (JPS) in healthy individuals. Study design. Repeated measures, within-subject design. Methods. Knee JPS was tested in 16 individuals with no history of knee pathology under three experimental conditions: baseline control, a distraction task and knee pain induced by injection of hypertonic saline into the infrapatellar fat pad. Knee JPS was measured using active ipsilateral limb matching responses at 20degrees and 60degrees flexion whilst non-weightbearing (NWB) and 20degrees flexion single leg stance. During the tasks, the subjective perception of distraction and severity of pain were measured using 11-point numerical rating scales. Results. Knee JPS was not altered by acute knee pain in any of the positions tested. The distraction task resulted in poorer concentration, greater JPS absolute errors at 20degrees NWB, and greater variability in errors during the WB tests. There were no significant correlations between levels of pain and changes in JPS errors. Changes in JPS with pain and distraction were inversely related to baseline knee JPS variable error in all test positions (r = -0.56 to -0.91) but less related to baseline absolute error. Conclusion. Knee JPS is reduced by an attention-demanding task but not by experimentally induced pain. (C) 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.

Expression and putative role of lactoseries carbohydrates present on NCAM in the rat primary olfactory pathway

Primary olfactory neurons project axons from the olfactory neuroepithelium lining the nasal cavity to,the olfactory bulb in the brain. These axons grow within large mixed bundles in the olfactory nerve and then sort out into homotypic fascicles in the nerve fiber layer of the olfactory bulb before terminating in topographically fixed glomeruli. Carbohydrates expressed on the cell surface have been implicated in axon sorting within the nerve fiber layer. We have identified two novel subpopulations of primary olfactory neurons that express distinct alpha-extended lactoseries carbohydrates recognised by monoclonal antibodies LA4 and KH10. Both carbohydrate epitopes are present on novel glycoforms of the neural cell adhesion molecule, which we have named NOC-7 and NOC-8. Primary axon fasciculation is disrupted in vitro when interactions between these cell surface lactoseries carbohydrates and their endogenous binding molecules are inhibited by the LA4 and KH10 antibodies or lactosamine sugars. We report the expression of multiple members of the lactoseries binding galectin family in the primary olfactory system. In particular, galectin-3 is expressed by ensheathing cells surrounding nerve fascicles in the submucosa and nerve fiber layer, where it may mediate cross-linking of axons. Galectin-4, -7, and -8 are expressed by the primary olfactory axons as they grow from the nasal cavity to the olfactory bulb. A putative role for NOC-7 and NOC-8 in axon fasciculation and the expression of multiple galectins in the developing olfactory nerve suggest that these molecules may be involved in the formation of this pathway, particularly in the sorting of axons as they converge towards their target. (C) 2004Wiley-Liss, Inc.

Quantification of the magnification and distortion effects of a pediatric flexible video-bronchoscope

Background: Flexible video bronchoscopes, in particular the Olympus BF Type 3C160, are commonly used in pediatric respiratory medicine. There is no data on the magnification and distortion effects of these bronchoscopes yet important clinical decisions are made from the images. The aim of this study was to systematically describe the magnification and distortion of flexible bronchoscope images taken at various distances from the object. Methods: Using images of known objects and processing these by digital video and computer programs both magnification and distortion scales were derived. Results: Magnification changes as a linear function between 100 mm ( x 1) and 10 mm ( x 9.55) and then as an exponential function between 10 mm and 3 mm ( x 40) from the object. Magnification depends on the axis of orientation of the object to the optic axis or geometrical axis of the bronchoscope. Magnification also varies across the field of view with the central magnification being 39% greater than at the periphery of the field of view at 15 mm from the object. However, in the paediatric situation the diameter of the orifices is usually less than 10 mm and thus this limits the exposure to these peripheral limits of magnification reduction. Intraclass correlations for measurements and repeatability studies between instruments are very high, r = 0.96. Distortion occurs as both barrel and geometric types but both types are heterogeneous across the field of view. Distortion of geometric type ranges up to 30% at 3 mm from the object but may be as low as 5% depending on the position of the object in relation to the optic axis. Conclusion: We conclude that the optimal working distance range is between 40 and 10 mm from the object. However the clinician should be cognisant of both variations in magnification and distortion in clinical judgements.

Performance of the Norwegian version of AUSCAN - a disease-specific measure of hand osteoarthritis

Objective: To examine the performance of the Norwegian version of the AUSCAN Index as a disease-specific health status measure in patients with hand osteoarthritis (OA). Methods: One hundred and ninety-nine patients with clinical hand OA (mean (SD) age 61.7 (5.7) years, 18 (9%) males) underwent a comprehensive examination including joint status, examination of grip strength and completion of several self-reported health status questionnaires. The Australian/Canadian OA hand index (AUSCAN) captures three different dimensions of hand OA: pain (5 items), stiffness (1 item), and difficulties with daily activities (9 items). Our pre-study hypothesis was to identify AUSCAN as a specific hand measure with strong correlations to hand measures and lower correlations to other general measures of health. Results: Patient completion of the AUSCAN Index was similar or better than other measures. The internal consistency of the AUSCAN was excellent. The pain and physical dimension of AUSCAN correlated substantially to, each other and moderately to the stiffness scale. The AUSCAN physical scale correlated moderately to substantially to other measures, the highest correlation being seen with the Arthritis Impact Measurement Scale (AIMS) 2 hand and finger function scale (r= 0.73). The standardised differences between patients with and without radiographic abnormalities were numerically larger for the AUSCAN pain and physical scales than for other measures. Conclusion: The Norwegian version of the AUSCAN has an acceptable clinimetric performance and is a suitable tool for assessment of hand OA. (C) 2005 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Randomized controlled trial of an educational intervention for managing fatigue in women receiving adjuvant chemotherapy for early-stage breast cancer

Purpose To evaluate the efficacy of a psychoeducational intervention in improving cancer-related fatigue. Patients and Methods This randomized controlled trial involved 109 women commencing adjuvant chemotherapy for stage I or II breast cancer in five chemotherapy treatment centers. Intervention group patients received an individualized fatigue education and support program delivered in the clinic and by phone over three 10- to 20-minute sessions 1 week apart. Instruments included a numeric rating scale assessing confidence with managing fatigue; 11-point numeric rating scales measuring fatigue at worst, average, and best; the Functional Assessment of Cancer Therapy-Fatigue and Piper Fatigue Scales; the Cancer Self-Efficacy Scale; the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30; and the Hospital Anxiety and Depression Scale. For each outcome, separate analyses of covariance of change scores between baseline (T1) and the three follow-up time points (T2, T3, and T4) were conducted, controlling for the variable's corresponding baseline value. Results Compared with the intervention group, mean difference scores between the baseline (T1) and immediate after the test (T2) assessments increased significantly more for the control group for worst and average fatigue, Functional Assessment of Cancer Therapy-Fatigue, and Piper fatigue severity and interference measures. These differences were not observed between baseline and T3 and T4 assessments. No significant differences were identified for any pre- or post-test change scores for confidence with managing fatigue, cancer self-efficacy, anxiety, depression, or quality of life. Conclusion Preparatory education and support has the potential to assist women to cope with cancer-related fatigue in the short term. However, further research is needed to identify ways to improve the potency and sustainability of psychoeducational interventions for managing cancer-related fatigue.

Adaptive management and its role in managing Great Barrier Reef water quality

Adaptive management is the pathway to effective conservation, use and management of Australia’s coastal catchments and waterways. While the concepts of adaptive management are not new, applications involving both assessment and management responses are indeed limited at the national and regional scales. This paper outlines the components of a systematic framework for linking scientific knowledge, existing tools, planning approaches and participatory processes to achieve healthy regional partnerships between community, industry, government agencies and science providers to overcome institutional barriers and uncoordinated monitoring. The framework developed by the Coastal CRC (www.coastal.crc.org.au/amf/amf_index.htm) is hierarchical in the way it displays information to allow associated frameworks to be integrated, and represents a construct in which processes, information, decision tools and outcomes are brought together in a structured and transparent way for adaptive catchment and coastal management. This paper proposes how an adaptive management approach could be used to benefit the implementation of the Reef Water Quality Protection Plan (RWQPP).

Theoretical and numerical analysis of large-scale heat transfer problems with temperature-dependent pore-fluid densities

Purpose - In many scientific and engineering fields, large-scale heat transfer problems with temperature-dependent pore-fluid densities are commonly encountered. For example, heat transfer from the mantle into the upper crust of the Earth is a typical problem of them. The main purpose of this paper is to develop and present a new combined methodology to solve large-scale heat transfer problems with temperature-dependent pore-fluid densities in the lithosphere and crust scales. Design/methodology/approach - The theoretical approach is used to determine the thickness and the related thermal boundary conditions of the continental crust on the lithospheric scale, so that some important information can be provided accurately for establishing a numerical model of the crustal scale. The numerical approach is then used to simulate the detailed structures and complicated geometries of the continental crust on the crustal scale. The main advantage in using the proposed combination method of the theoretical and numerical approaches is that if the thermal distribution in the crust is of the primary interest, the use of a reasonable numerical model on the crustal scale can result in a significant reduction in computer efforts. Findings - From the ore body formation and mineralization points of view, the present analytical and numerical solutions have demonstrated that the conductive-and-advective lithosphere with variable pore-fluid density is the most favorite lithosphere because it may result in the thinnest lithosphere so that the temperature at the near surface of the crust can be hot enough to generate the shallow ore deposits there. The upward throughflow (i.e. mantle mass flux) can have a significant effect on the thermal structure within the lithosphere. In addition, the emplacement of hot materials from the mantle may further reduce the thickness of the lithosphere. Originality/value - The present analytical solutions can be used to: validate numerical methods for solving large-scale heat transfer problems; provide correct thermal boundary conditions for numerically solving ore body formation and mineralization problems on the crustal scale; and investigate the fundamental issues related to thermal distributions within the lithosphere. The proposed finite element analysis can be effectively used to consider the geometrical and material complexities of large-scale heat transfer problems with temperature-dependent fluid densities.

Species accumulation curves and their applications in parasite ecology

Species accumulation curves (SACs) chart the increase in recovery of new species as a function of some measure of sampling effort. Studies of parasite diversity can benefit from the application of SACs, both as empirical tools to guide sampling efforts and predict richness, and because their properties are informative about community patterns and the structure of parasite diversity. SACs can be used to infer interactivity in parasite infra-communities, to partition species richness into contributions from different spatial scales and different levels of the host hierarchy (individuals, populations and communities) or to identify modes of community assembly (niche versus dispersal). A historical tendency to treat individual hosts as statistically equivalent replicates (quadrats) seemingly satisfies the sample-based subgroup of SACs but care is required in this because of the inequality of hosts as sampling units. Knowledge of the true distribution of parasite richness over multiple host-derived and spatial scales is far from complete but SACs can improve the understanding of diversity patterns in parasite assemblages.

Developing a categorisation system for rapists' speech

Case linkage, the linking of crimes into series, is used in policing in the UK and other countries. Previous researchers have proposed using rapists' speech in this practice; however, researching this application requires the development of a reliable coding system for rapists' speech. A system was developed based on linguistic theories of pragmatics which allowed for the categorization of an utterance into a speech act type (e.g. directive). Following this classification, the qualitative properties of the utterances (e.g. the degree of threat it carried) could be captured through the use of rating scales. This system was tested against a previously developed system using 188 rapists' utterances taken from victims' descriptions of rape. The pragmatics-based system demonstrated higher inter-rater reliability whilst enabling the classification of a greater number of rapists' utterances. Inter-rater reliability for the subscales was also tested using a sub-sample of 50 rapists' utterances and inter-item correlations were calculated. Seventy-six per cent of the subscales had satisfactory to high inter-rater reliability. Based on these findings and the inter-item correlations, the classification system was revised. The potential use of this system for the practices of case linkage and offender profiling is discussed.

The primal sketch revisited: locating and representing edges in human vision via Gaussian-derivative filtering

Marr's work offered guidelines on how to investigate vision (the theory - algorithm - implementation distinction), as well as specific proposals on how vision is done. Many of the latter have inevitably been superseded, but the approach was inspirational and remains so. Marr saw the computational study of vision as tightly linked to psychophysics and neurophysiology, but the last twenty years have seen some weakening of that integration. Because feature detection is a key stage in early human vision, we have returned to basic questions about representation of edges at coarse and fine scales. We describe an explicit model in the spirit of the primal sketch, but tightly constrained by psychophysical data. Results from two tasks (location-marking and blur-matching) point strongly to the central role played by second-derivative operators, as proposed by Marr and Hildreth. Edge location and blur are evaluated by finding the location and scale of the Gaussian-derivative `template' that best matches the second-derivative profile (`signature') of the edge. The system is scale-invariant, and accurately predicts blur-matching data for a wide variety of 1-D and 2-D images. By finding the best-fitting scale, it implements a form of local scale selection and circumvents the knotty problem of integrating filter outputs across scales. [Supported by BBSRC and the Wellcome Trust]

Spatial and temporal dependencies of cross-orientation suppression in human vision.

A well-known property of orientation-tuned neurons in the visual cortex is that they are suppressed by the superposition of an orthogonal mask. This phenomenon has been explained in terms of physiological constraints (synaptic depression), engineering solutions for components with poor dynamic range (contrast normalization) and fundamental coding strategies for natural images (redundancy reduction). A common but often tacit assumption is that the suppressive process is equally potent at different spatial and temporal scales of analysis. To determine whether it is so, we measured psychophysical cross-orientation masking (XOM) functions for flickering horizontal Gabor stimuli over wide ranges of spatio-temporal frequency and contrast. We found that orthogonal masks raised contrast detection thresholds substantially at low spatial frequencies and high temporal frequencies (high speeds), and that small and unexpected levels of facilitation were evident elsewhere. The data were well fit by a functional model of contrast gain control, where (i) the weight of suppression increased with the ratio of temporal to spatial frequency and (ii) the weight of facilitatory modulation was the same for all conditions, but outcompeted by suppression at higher contrasts. These results (i) provide new constraints for models of primary visual cortex, (ii) associate XOM and facilitation with the transient magno- and sustained parvostreams, respectively, and (iii) reconcile earlier conflicting psychophysical reports on XOM.

The contextual evaluation of research on sexually explicit materials

This thesis criticises many psychological experiments on 'pornography' which attempt to demonstrate how 'pornography' causes and/or equals rape. It challenges simplistic definitions of 'pornography', arguing that sexually explicit materials (SEM) are constructed and interpreted in a number of different ways; and demonstrates that how, when and where materials are depicted or viewed will influence perceptions and reactions. In addition, it opposes the overreliance on male undergraduates as participants in 'porn' research. Theories of feminist psychology and reflexivity are used throughout the thesis, and provide a detailed contextual framework in a complex area. Results from a number of interlinking studies which use a variety of methodological approaches (focus groups, questionnaires and content analysis), indicate how contextual issues are omitted in much existing research on SEM. These include the views and experiences participants' hold prior to completing SEM studies; their opinions about those who 'use' 'pornography'; their understanding of key terms linked with SEM (eg: pornography and erotica); and discussions of sexual magazines aimed at male and female audiences. Participants' reactions to images and texts associated with SEM presented in different contexts are discussed. Three main conclusions are drawn from this thesis. Firstly, images deemed 'pornographic' differ through historical and cultural periods' and political, economic and social climates, so 'experimental' approaches may not always be the most appropriate research tool. Secondly, there is not one definition, source, or factor which may be named 'pornography'; and thirdly the context and presentation of materials influence how images are perceived and reacted to. The thesis argues a number of factors influence view of 'pornography', suggesting SEM may be 'in the eye of the beholder'.