876 research outputs found
A formal development framework and its use to manage software production
Within an ESPRIT project called FORMAST the authors devised the concept of a ƒorm to bring together all aspects of the development of a 'module' (i.e. specification, design and verification) within a distributed asynchronous system. The use of ƒorms can be extended to other compositional system development scenarios. Using ƒorms in a top-down fashion means that the logical interaction between the modules already designed and the formal specifications of modules required to complete the implementation can readily be ascertained. Moreover, this can be done at any stage of development. Thus one can maintain an overall view of the entire system design and use this to monitor the progress of program construction. This then provides a notion of traceability from a management standpoint
INTER-TRIAL VARIABILITY IN KINEMATIC DESCRIPTORS OF GAIT
The purpose of this study was to determine the inter-trial variability of kinematic descriptors of human gait. A case study subject with spastic hemiplegic gait following traumatic event was analyzed for kinematic differences pertreatment, 1-week post-treatment and 4-weeks post-treatment. The treatment protocol included a focal dennervation of the spastic gastrocnemius muscle on the affected side of the body. Data was collected via three 60 Hz S-VHS camcorders set at a shutter speed of 11100 second. Each camera was placed at approximately a 30 degree angle with respect to the optical axis of the other two cameras. Ten trials of walking gait at a self-selected pace were recorded for both the affected and unaffected sides for two complete strides. Kinetic data was recorded during a single stance phase simultaneous with the kinematic data. The three views were synchronized using a single pulse from a standard flash unit. The three planer views were transformed to three-dimensional coordinates using a Direct Linear Transformation (DLT) as part of the Ariel Performance Analysis System (APAS). Each joint center location as smoothed individually by selecting the proper cutoff frequency of a double-pass recursive Butterworth filter via an inspection of the joint center's power spectrum. Joint angular displacements of the ankle, knee and hip were compared across the ten trials for each leg individually using a univariate analysis of variance (ANOVA). The pre-treatment and two post-treatment conditions were analyzed separately. Non-significant inter-trial differences were found for each variable and each leg across the data collection periods. Given the proliferation and gait analysis as a clinical tool, as well as a research device for exercise and sport, demonstration of the efficacy and reliability of this analysis is essential
Characterization of metal ion-induced [3H]inositol hexakisphosphate binding to rat cerebellar membranes
The binding of [3H]inositol hexakisphosphate ([3H] InsP6) to rat cerebellar membranes has been characterized with the objective of establishing the role, if any, of a membrane protein receptor. In the presence of EDTA, we have previously identified an InsP6-binding site with a capacity of approximately 20 pmol/mg protein (Hawkins, P. T., Reynolds, D. J. M., Poyner, D. R., and Hanley, M. R. (1990) Biochem. Biophys. Res. Commun. 167, 819-827). However, in the presence of 1 mM Mg2+, the capacity of [3H]InsP6 binding to membranes was increased approximately 9-fold. This enhancing effect of Mg2+ was reversed by addition of 10 microM of several cation chelators, suggesting that the increased binding required trace quantities of other metal cations. This is supported by experiments where it was possible to saturate binding by addition of excess membranes, despite not significantly depleting radioligand, pointing to removal of some other factor. Removal of endogenous cations from the binding assay by pretreatment with chelex resin also prevents the Mg(2+)-induced potentiation. Consideration of the specificity of the chelators able to abolish this potentiation suggested involvement of Fe3+ or Al3+. Both these ions (but not several others) were able to increase [3H]InsP6 binding to chelex-pretreated membranes at concentrations of 1 microM. It is possible to demonstrate synergy between Fe3+ and Mg2+ under these conditions. We propose that [3H]InsP6 may interact with membranes through non-protein recognition possibly via phospholipids, in a manner dependent upon trace metals. The implications of this for InsP6 biology are considered
Differences in location and electrophyslologic properties of atrial tachycardias in structurally normal and abnormal hearts
Structural, item, and test generalizability of the psychopathology checklist - revised to offenders with intellectual disabilities
The Psychopathy Checklist–Revised (PCL-R) is the most widely used measure of psychopathy in forensic clinical practice, but the generalizability of the measure to offenders with intellectual disabilities (ID) has not been clearly established. This study examined the structural equivalence and scalar equivalence of the PCL-R in a sample of 185 male offenders with ID in forensic mental health settings, as compared with a sample of 1,212 male prisoners without ID. Three models of the PCL-R’s factor structure were evaluated with confirmatory factor analysis. The 3-factor hierarchical model of psychopathy was found to be a good fit to the ID PCL-R data, whereas neither the 4-factor model nor the traditional 2-factor model fitted. There were no cross-group differences in the factor structure, providing evidence of structural equivalence. However, item response theory analyses indicated metric differences in the ratings of psychopathy symptoms between the ID group and the comparison prisoner group. This finding has potential implications for the interpretation of PCL-R scores obtained with people with ID in forensic psychiatric settings
Music in advertising and consumer identity: The search for Heideggerian authenticity
This study discusses netnographic findings involving 472 YouTube postings categorized to identify themes regarding consumers’ experience of music in advertisements. Key themes relate to musical taste, musical indexicality, musical repetition and musical authenticity. Postings reveal how music conveys individual taste and is linked to personal memories and Heidegger’s coincidental time where moments of authenticity may be triggered in a melee of emotions, memories and projections. Identity protection is enabled as consumers frequently resist advertisers’ attempts to use musical repetition to impose normative identity. Critiques of repetition in the music produce Heideggerian anxiety leading to critically reflective resistance. Similarly, where advertising devalues the authenticity of iconic pieces of music, consumers often resist such authenticity transgressions as a threat to their own identity. The Heideggerian search for meaning in life emphasizes the significance of philosophically driven ideological authenticity in consumers’ responses to music in advertisements
A computationally tractable version of the collective model
A computationally tractable version of the Bohr-Mottelson collective model is
presented which makes it possible to diagonalize realistic collective models
and obtain convergent results in relatively small appropriately chosen
subspaces of the collective model Hilbert space. Special features of the
proposed model is that it makes use of the beta wave functions given
analytically by the softened-beta version of the Wilets-Jean model, proposed by
Elliott et al., and a simple algorithm for computing SO(5) > SO(3) spherical
harmonics. The latter has much in common with the methods of Chacon, Moshinsky,
and Sharp but is conceptually and computationally simpler. Results are
presented for collective models ranging from the sherical vibrator to the
Wilets-Jean and axially symmetric rotor-vibrator models.Comment: 16 pages, 9 figure
Predicting specific impulse distributions for spherical explosives in the extreme near-field using a Gaussian function
Accurate quantification of the blast load arising from detonation of a high explosive has applications in transport security, infrastructure assessment and defence. In order to design efficient and safe protective systems in such aggressive environments, it is of critical importance to understand the magnitude and distribution of loading on a structural component located close to an explosive charge. In particular, peak specific impulse is the primary parameter that governs structural deformation under short-duration loading. Within this so-called extreme near-field region, existing semi-empirical methods are known to be inaccurate, and high-fidelity numerical schemes are generally hampered by a lack of available experimental validation data. As such, the blast protection community is not currently equipped with a satisfactory fast-running tool for load prediction in the near-field. In this article, a validated computational model is used to develop a suite of numerical near-field blast load distributions, which are shown to follow a similar normalised shape. This forms the basis of the data-driven predictive model developed herein: a Gaussian function is fit to the normalised loading distributions, and a power law is used to calculate the magnitude of the curve according to established scaling laws. The predictive method is rigorously assessed against the existing numerical dataset, and is validated against new test models and available experimental data. High levels of agreement are demonstrated throughout, with typical variations of <5% between experiment/model and prediction. The new approach presented in this article allows the analyst to rapidly compute the distribution of specific impulse across the loaded face of a wide range of target sizes and near-field scaled distances and provides a benchmark for data-driven modelling approaches to capture blast loading phenomena in more complex scenarios
Учебная история болезни по внутренним болезням и военно-полевой терапии
ВНУТРЕННИЕ БОЛЕЗНИВОЕННО-ПОЛЕВАЯ ТЕРАПИЯИСТОРИЯ БОЛЕЗНИМЕТОДИЧЕСКИЕ УКАЗАНИЯМетодические указания учат студентов правильно оформлять историю болезни пациента
A cell cycle model for somitogenesis: mathematical formulation and numerical simulation
After many years of research, the mechanisms that generate a periodic pattern of repeated elements (somites) along the length of the embryonic body axis is still one of the major unresolved problems in developmental biology. Here we present a mathematical formulation of the cell cycle model for somitogenesis proposed in Development105 (1989), 119–130. Somite precursor cells in the node are asynchronous, and therefore, as a population, generate continuously pre-somite cells which enter the segmental plate. The model makes the hypothesis that there exists a time window within the cell cycle, making up one-seventh of the cycle, which gates the pre-somite cells so that they make somites discretely, seven per cycle. We show that the model can indeed account for the spatiotemporal patterning of somite formation during normal development as well as the periodic abnormalities produced by heat shock treatment. We also relate the model to recent molecular data on the process of somite formation
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