Spontaneous alternation behavior in Paramecium

Spontaneous alternating behavior (SAB), the tendency of an organism to successively turn left and right in a maze, is a standard metric of short-term memory in developmental and pyschopharmacological studies. Although SAB is perhaps the most phylogenetically widespread behavior in motile lifeforms, conflicting data on SAB exist for several sets of closely related taxa. For example, previous studies provide contradictory evidence concerning the existence of spontaneous alternation behavior in the protozoanParamecium. However, these studies tested different species, using very different experimental designs. Using a single, factorial design for both previously tested species,P. multimicronucleatum andP. caudatum, we found that, in fact, the two species do not differ in their alternation behavior; specifically, they alternate in mazes with short tracks, but not in mazes with long tracks. These results are in accord with alternation studies on other taxa, and they fully resolve the apparent contradictions in the earlier studies onParamecium. They also indicate that caution should be used in interpreting variable results across species tested with different experimental designs and suggest that, in at least some taxa, SAB may not be strictly dependent on the use of short-term memory.     

通过话轮交替模式分析《茶花女》中的人物性格

本文运用会话分析中的话轮交替模式来分析Alexandre Dumas fils的剧本《茶花女》第九章的一段对话,展示戏剧中人物性格。本文中具体分析话轮交替机制主要包括的三个方面,即话轮分配、话轮分布和话轮序列。     

Filtering methods for content-based retrieval on indexed symbolic music databases

We introduce fast filtering methods for content-based music retrieval problems, where the music is modeled as sets of points in the Euclidean plane, formed by the (on-set time, pitch) pairs. The filters exploit a precomputed index for the database, and run in time dependent on the query length and intermediate output sizes of the filters, being almost independent of the database size. With a quadratic size index, the filters are provably lossless for general point sets of this kind. In the context of music, the search space can be narrowed down, which enables the use of a linear sized index for effective and efficient lossless filtering. For the checking phase, which dominates the overall running time, we exploit previously designed algorithms suitable for local checking. In our experiments on a music database, our best filter-based methods performed several orders of a magnitude faster than the previously designed solutions.     

Training on the project: a quantifying approach to competence development

In the project ‘Competence-Driven Project Portfolio Analysis’ (CDPPA), an integrated system for supporting R&D project selection, staff assignment and activity scheduling with special consideration of the strategic development of competencies has been designed and implemented prototypically. The system has been field-tested at the Electronic Commerce Competence Center (EC3), a public–private partnership R&D enterprise. Experiences from this trial application are summarised and discussed, particularly concerning data collection and competence measurement, the benefits and limits of the chosen multi-criteria decision analysis approach, the evaluation of introduced changes to the decision-making processes, and the transparency of the formal planning model and its components.     

Harnessing collective intelligence of Web 2.0: group adoption and use of Internet-based collaboration technologies

Along with the advent of Web 2.0, mass collaboration is of paramount importance in knowledge exploration and diffusion. However, the extent to which Internet-based collaboration technologies can be used to develop new knowledge and to leverage the wisdom of crowds heavily depends on the collective willingness to adopt such tools together. In this study, the adoption and use of instant messaging has been conceptualized as a group-referent intentional social action. The concept of ‘we-intention’, which refers to one's perception of the group acting as a unit, is the focus of our interest. The cognitive, affective and social dimensions that contribute to ‘we-intention’ to adopt and use instant messaging were investigated. A survey was conducted and the findings provided empirical evidence supporting the idea that cognitive, affective and social factors jointly lead to the development of we-intention. This study is expected to provide some useful insights to both researchers and practitioners.     

Investigating the role of a Web-based tool to promote collective knowledge in medical communities

The paper reports a case study where a relatively lightweight technology in the form of a Web-based questionnaire was used to support members of a real community of professionals in externalizing and sharing their good practices and achieving a better awareness of and agreement on topics of common interest. We focused on an important medical association that counts more 1000 doctors all around the world as its members. In particular, we report how this association used the occasion of the on-line survey enabled by our technology to increase the awareness of its members about the actual heterogeneity of preferences existing in their daily clinical practice, and to trigger discussion toward a better consensus on best practices, appropriate indications, and treatments of choice for their profession and practice. We also report the result of a post-hoc evaluation of the Web-based technology employed, and draw some implications for the better design of this kind of tool in order to collect and share collective knowledge in specific professional domains.     

Serum thyroglobulin antibody levels within or near to the reference range may interfere with thyroglobulin measurement

High concentration of thyroglobulin antibodies (TgAb) is a major limiting factor of thyroglobulin measurements in patients with differentiated thyroid cancer. We investigated whether thyroglobulin antibody added to serum samples could interfere with the thyroglobulin assay. Thyroglobulin levels in serum samples with different concentrations of thyroglobulin were measured by electrochemiluminescence immunoassay before and after the addition of increasing concentrations of thyroglobulin antibody using the secondary calibrator solution of the thyroglobulin assay kit containing sheep thyroglobulin antibody to reach thyroglobulin antibody levels within or near to the reference range. Thyroglobulin and thyroglobulin antibody concentrations were also measured in 134 serum samples from 27 patients after thyroid ablation. There was a strong negative association (slope = −1.179) between thyroglobulin antibody and thyroglobulin concentrations in samples with added thyroglobulin antibody (beta = −0.86; P < 0.001). Changes in thyroglobulin concentrations were described mathematically as loss of thyroglobulin% = −0.2408 × Ln(thyroglobulin antibody IU/ml) + 0.1944. Thyroglobulin concentrations were significantly lower than those calculated from experiments with added thyroglobulin antibody in 26/134 samples from patients after thyroid ablation. We conclude that if the same TgAb interference exists in the presence of naturally occurring human TgAb, our observation may prove to be useful during follow-up of patients with differentiated thyroid cancer. However, further studies are needed to explore the clinical relevance of thyroglobulin antibody levels within or near to the reference range in monitoring these patients.     

On the influence of the architecture of poly(ethylene glycol)-based thermoresponsive polymers on cell adhesion

Thermoresponsive polymer surface coatings are a promising tool for cell culture applications. They allow for a mild way of cell detachment that preserves the activity of membrane proteins—a prerequisite for reliable cell analysis. To enlarge the application range of these coatings to cells with different adhesion properties, we synthesized various novel poly(ethylene glycol)-based thermoresponsive polymers and describe how (i) their chemical structure and (ii) their surface density affect their efficiency. In order to quantify the influence of both factors, the time for cell spreading and rounding efficiency were observed. As a result, efficiency of cell rounding, which is closely correlated to cell detachment, is less affected by both factors than the time needed for cell spreading. This time can effectively be adjusted by the molecular architecture which includes the length of the polymer backbone and the side chains. Based on this work, recommendations are given for future optimization of functionality of thermoresponsive polymer coatings for cell culture applications.     

Approximation based on orthogonal and almost orthogonal functions

In this paper, we define a class of almost orthogonal rational functions of Legendre type in a new manner. Relations of these functions with classical exponentional functions orthogonal over interval (0, ∞), as well as classical polynomials orthogonal over (0, 1) are explained. Defining relations of these functions can be used for designing almost orthogonal filters. These filters are generators of orthogonal signals and can be successfully applied in finding the best signal approximation in the sense of the mean square error. The filters orthogonal property enables building of physical (in this case electrical) models of dynamical systems (the sources of signals to be approximated) either with less components for the same model accuracy or higher accuracy for the same number of components than the other known models. New filters represent further improvement of previously designed filters, by the same authors, in the sense of simplicity, higher accuracy, lesser approximation time and even a possibility to approximate signals generated by systems with built-in imperfections. Series of experiments were performed to analyze the dependence of approximation accuracy and the number of filters sections.