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Independent Groups (independent + groups)
Selected AbstractsThe local lymph node assay and the assessment of relative potency: status of validationCONTACT DERMATITIS, Issue 2 2007David A. Basketter For the prediction of skin sensitization potential, the local lymph node assay (LLNA) is a fully validated alternative to guinea-pig tests. More recently, information from LLNA dose,response analyses has been used to assess the relative potency of skin sensitizing chemicals. These data are then deployed for risk assessment and risk management. In this commentary, the utility and validity of these relative potency measurements are reviewed. It is concluded that the LLNA does provide a valuable assessment of relative sensitizing potency in the form of the estimated concentration of a chemical required to produce a threefold stimulation of draining lymph node cell proliferation compared with concurrent controls (EC3 value) and that all reasonable validation requirements have been addressed successfully. EC3 measurements are reproducible in both intra- and interlaboratory evaluations and are stable over time. It has been shown also, by several independent groups, that EC3 values correlate closely with data on relative human skin sensitization potency. Consequently, the recommendation made here is that LLNA EC3 measurements should now be regarded as a validated method for the determination of the relative potency of skin sensitizing chemicals, a conclusion that has already been reached by a number of independent expert groups. [source] French adaptation and preliminary validation of a questionnaire to evaluate understanding of informed consent documents in phase I biomedical researchFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2006Adeline Paris Abstract The content of informed consent documents (ICD) is a crucial element in the process of providing information to participants in biomedical research. Clear comprehension of the information, i.e. the ability to understand its meaning and its consequences, is of utmost importance. The objective of this study was to describe the different steps in the French adaptation and preliminary validation of the Qualité de Compréhension des Formulaires d'information et de consentement (QCFic) questionnaire (http://www.lyon.inserm.fr/cic-grenoble) based on the American Quality of Informed Consent (QuIC) questionnaire. Adaptation and preliminary validation of the QuIC for use in France was composed of five principal steps: translation, scientific validation, lexical validation, edition of gold-standard answers and a pilot study. Each stage was conducted by independent groups of experts, under the coordination of the study board. Thirteen questions were added and one was suppressed. Two steps were required for the scientific validation and for lexical validation, 21 modifications were proposed. Relative to gold-standard answers, the three experts gave the same answer for 24 questions and for nine other questions, two of the three gave identical answers, which were validated by the study board. Results of a pilot study showed a global QCFic score of 88.99 (84.13,90.92) and no specific commentary was made about the content of the questions, so no more modification needed to be made. A preliminary validated French questionnaire, the QCFic, is now available to evaluate the quality of an informed consent document in phase I clinical trials. It is quick and easy to use. [source] A stochastic modelling approach to describing the dynamics of an experimental furunculosis epidemic in Chinook salmon, Oncorhynchus tshawytscha (Walbaum)JOURNAL OF FISH DISEASES, Issue 2 2007H Ogut Abstract A susceptible-infected-removed (SIR) stochastic model was compared to a susceptible-latent-infectious-removed (SLIR) stochastic model in terms of describing and capturing the variation observed in replicated experimental furunculosis epidemics, caused by Aeromonas salmonicida. The epidemics had been created by releasing a single infectious fish into a group of susceptible fish (n = 43) and progress of the epidemic was observed for 10 days. This process was replicated in 70 independent groups. The two stochastic models were run 5000 times and after every run and every 100 runs, daily mean values of each compartment were compared to the observed data. Both models, the SIR model (R2 = 0.91), and the SLIR model (R2 = 0.90) were successful in predicting the number of fish in each category at each time point in the experimental data. Moreover, between-replicate variability in the stochastic model output was similar to between-replicate variability in the experimental data. Generally, there was little change in the goodness of fit (R2) after 200 runs in the SIR model whereas 500 runs were necessary to have stable predictions with the SLIR model. In the SIR model, on an individual replicate basis, ,80% of 5000 simulated replicates had R2 = 0.7 and above, whereas this ratio was slightly higher (82%) with the SLIR model. In brief, both models were equally effective in predicting the observed data and its variance but the SLIR model was advantageous because it differentiated the latent, i.e. infected but not having the ability to discharge pathogen, from the infectious fish. [source] An unsupervised classification method of uterine electromyography signals: Classification for detection of preterm deliveriesJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2009M. O. Diab Abstract Aim:, This article proposes an unsupervised classification method that can be applied to the electromyography signal of uterine contractions for the detection of preterm birth. Methods:, The frequency content of the electromyography changes from one woman to another, and during pregnancy, so wavelet decomposition is first used to extract the parameters of each contraction, and an unsupervised statistical classification method based on Fisher's test is used to classify the events. A principal component analysis projection is then used as evidence of the groups resulting from this classification. Another method of classification based on a competitive neural network is also applied on the same signals. Both methods are compared. Results:, Results show that uterine contractions may be classified into independent groups according to their frequency content and according to term (either at recording or at delivery). [source] The relationship between risk and insight in a high-security forensic settingJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 5 2003P. WOODS RMN phDDip Health Care Research It is often intimated amongst practitioners in mental healthcare that clients who display poor insight either into their mental health or behaviour present a greater risk either to themselves or others. This paper reports relationships found between the risk and insight subscales of the Behavioural Status Index. This is an instrument designed specifically for healthcare practitioners to measure health functioning amongst mental health clients, in particular those in forensic mental healthcare. Data were collected, using a repeated measures method by primary nurses, from a sample of 503 patients in two high-security mental health hospitals. Seven factors emerged through factor analysis. The first of these contained all the insight items. Significant differences were found on a number of factors between independent groups. Generally, results indicate that patients on lower dependency wards scored more normatively on the factors, adding to instrument validity. Men were found to score more normatively than women. Clinical practice implications and ongoing European studies examining the use of the instrument in clinical practice and its association with treatment planning are discussed. [source] Azimuthally symmetric theory of gravitation , I. On the perihelion precession of planetary orbitsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2010G. G. Nyambuya ABSTRACT From a purely non-general relativistic standpoint, we solve the empty space Poisson equation (,2,= 0) for an azimuthally symmetric setting (i.e. for a spinning gravitational system like the Sun). We seek the general solution of the form ,=,(r, ,). This general solution is constrained such that in the zeroth-order approximation it reduces to Newton's well-known inverse square law of gravitation. For this general solution, it is seen that it has implications on the orbits of test bodies in the gravitational field of this spinning body. We show that to second-order approximation, this azimuthally symmetric gravitational field is capable of explaining at least two things: (i) the observed perihelion shift of solar planets; (ii) the fact that the mean Earth,Sun distance must be increasing (this resonates with the observations of two independent groups of astronomers, who have measured that the mean Earth,Sun distance must be increasing at a rate between about 7.0 ± 0.2 m century,1 and 15.0 ± 0.3 m cy,1). In principle, we are able to explain this result as a consequence of the loss of orbital angular momentum; this loss of orbital angular momentum is a direct prediction of the theory. Further, we show that the theory is able to explain at a satisfactory level the observed secular increase in the Earth year (1.70 ± 0.05 ms yr,1). Furthermore, we show that the theory makes a significant and testable prediction to the effect that the period of the solar spin must be decreasing at a rate of at least 8.00 ± 2.00 s cy,1. [source] Oscillations in growth of multicellular tumour spheroids: a revisited quantitative analysisCELL PROLIFERATION, Issue 4 2010A. S. Gliozzi Objectives:, Multicellular tumour spheroids (MTS) provide an important tool for study of the microscopic properties of solid tumours and their responses to therapy. Thus, observation of large-scale volume oscillations in MTS, reported several years ago by two independent groups (1,2), in our opinion represent a remarkable discovery, particularly if this could promote careful investigation of the possible occurrence of volume oscillations of tumours ,in vivo'. Materials and methods:, Because of high background noise, quantitative analysis of properties of observed oscillations has not been possible in previous studies. Such an analysis can be now performed, thanks to a recently proposed approach, based on formalism of phenomenological universalities (PUN). Results:, Results have provided unambiguous confirmation of the existence of MTS volume oscillations, and quantitative evaluation of their properties, for two tumour cell lines. Proof is based not only on quality of fitting of the experimental datasets, but also on determination of well-defined values of frequency and amplitude of the oscillations for each line investigated, which would not be consistent with random fluctuation. Conclusions:, Biological mechanisms, which can be directly responsible for observed oscillations, are proposed, which relates also to recent work on related topics. Further investigations, both at experimental and at modelling levels, are also suggested. Finally, from a methodological point of view, results obtained represent further confirmation of applicability and usefulness of the PUN approach. [source] | ||||||||||