Band 8, Heft 2

Background In the Virtual patient system Web-SP, the case authoring is entirely delegated to faculty. An analysis of the virtual patients (VPs) authored by faculty showed that the most common practice chosen by the case authors was to provide an introductory clinical vignette including rich anamnestic data. To evaluate the influence of the vignette, a controlled trial was conducted to determine if the absence of vignette would influence the students� therapeutic decisions and their clinical reasoning. Methods This double blind controlled trial randomized 57 fourth year dentistry students into two groups. Two virtual patient cases were created with the same content in both groups, but the VPs encountered by the intervention group lacked the introductory vignette. The therapy decisions and the history taking activity were scored and analysed by the course director. A stratified analysis was undertaken, stratifying by day. Results There were no statistically significant differences between the two groups with respect to their therapeutic decision scores (p=.16). Participants in both groups were equivalent with respect to the number of relevant medical history questions asked (p=.33) and the number of irrelevant questions asked (p=.20) Conclusions This study indicates that vignettes did not have an impact on students' clinical reasoning process. The use of detailed vignettes or case introductions might not be needed. A possible reason includes students� prior exposure for a full semester to other VPs for course work and clinical reasoning. Perhaps the intervention was too subtle to impact on learners at this stage of development. Clinical vignettes might have more impact at earlier stages of student learning such as early in the semester but not as preparation for final exam. The limited number of participants may have concealed differences between the groups. We also need to investigate if the one-hour limit given the students might influence the therapeutic decisions.

The applicability of the model for protein folding process simulation is presented using as the test two homologous proteins of different fold: helical in 3BD1 and beta-structural form in 2PIJ [L. van Dorn, T. Newlove, S. Chang, W. Ingram, M. Cordes. Biochemistry 45, 10542 (2006)]. The folding process is assumed to be directed by hydrophobic core directing the hydrophobic residues toward the center of the molecule and exposing the hydrophilic residues on the surface. The fuzzy oil drop model is expressed by the 3-dimensional Gauss function which mimics the external force field. The value of Gauss function is interpreted as the hydrophobicity density calculated in any point of the space of the protein body. The accordance of idealized and observed hydrophobicity distributions (calculated according to Levitt function) measured using the Kullback-Leibler divergence entropy reveals good accordance in two homological proteins of different folds. The structural differences appeared to be easily explainable on the basis of fuzzy oil drop model.

The divergence entropy: O/T and O/R measuring the distance between observed/theoretical and observed/random distributions was applied to identify the category of protein structures in respect to the hydrophobic core in protein molecules. The naive interpretation was applied treating the proteins of O/T < O/R as the molecules of hydrophobic core accordant with the theoretically assumed. The proteins of O/T > O/R are treated as representing the hydrophobic core not accordant with the assumed one. The large scale computing was performed (PDB data set) to reveal whether other than simple inequality relation should be used for this identification. The cluster analysis was applied to identify the relation O/T versus O/R as the discrimination factor to classify the category of proteins in respect to their structural form of hydrophobic core.

This research investigates the applicability of F. Davis' Technology Acceptance Model (TAM) to OCR-based CAPTCHAs involved in a free e-mail accounts registration process. The results provide preliminary evidence that the model may be a useful tool for research focused on acceptance of CAPTCHAs. The results are especially interesting when it comes to the concept of perceived usefulness and its direct relationship to the concept of attitude toward use. This relation indicates a new area of research for CAPTCHA developers interested in improving usability and accessibility of these systems.

The paper presents the use of a diagnostics device Posturometer-S applied to examine body posture in hearing impaired children. 46 subjects from the Maria Grzegorzewska School and Education Centre for Hard-of-Hearing Children in Wrocław were examined. The research was conducted through the use of a Posturometer-S, which is an electronic, non-invasive measuring device attached to a computer. It enables not only the imaging and evaluation of frontal and sagittal curves of the spine, but also spinal mobility. Previous research has indicated that incorrect body posture was more often observed in hearing impaired children than in healthy ones. Hence, constant control over body posture in children with hearing loss seems vital. Correct body posture has a great influence on functioning of the entire body. The results obtained by using the Posturometer-S and anthropological measurements helped to determine the types of body posture and postural defects in the examined subjects. The apparatus used in research enabled to determine the occurrence of kyphotic, lordotic and balanced body postures, the results as follows: incorrect kyphotic postures - 10,9% of the subjects, incorrect lordotic postures - 6,4% and incorrect balanced postures - 10,9% of the examined subjects. Correct body postures were observed in 67,4% of the examined children. The most frequent body posture abnormalities were: thoracic scoliosis (19,6%) and shoulder asymmetry (26,1%). Due to the screening tests, some children were referred for further diagnostic evaluation and physiotherapy.

Several advanced techniques for statistical analysis of nominal data were discussed to show how interesting associations between examined variables can be obtained using correspondence analysis, logistic regression and log-linear models. All these techniques are introduced on the example of medical data connected with the patients being on the curative diet. The studied data concerns four nominal variables: breaking the diet, overcoming diseases requiring the curative diet, sex and age of patient. Applied analyses were used for searching which of factors mentioned above influence on breaking the diet. The most popular technique in this case, chi-squared test of independence, indicates that only the age and illnesses overcoming before are related with breaking the diet whereas the sex is factor which does not have any relationship with the diet breaking. However, the deeper analysis revealed that we can not omit this variable in our research. Application of more compound statistical methods show the importance of age and sex in breaking the curative diet in detail. Presented methodology can be successfully applied not only in medicine but to data coming from different branches of science as well.

The recurrent 24 hours oscillations of biological activities which are generally called circadian rhythms are considered to be a mechanism allowing synchronisation of biological processes. The oscillations are generated by operation of special clock-like intra-cell devices comprising commonly transcription-translation processes as basis of measuring the time. The clock mechanism is controlled by two cooperating working out-of-phase negative feedback loops. Directly the oscillations are driven by steering signals changing the adjustment of feedback loops. They are created de novo in each cycle by complexation of synthesized proteins after their concentration reaches suitably high values. The complexes inhibit the protein synthesis in the own system while inducing it simultaneously in the cooperating one initiating in this way the next oscillation wave. The inhibition of protein synthesis is correlated with the degradation of already synthesizes molecules allowing the return to starting point of oscillation. The alignment of the proper phase of peripheral tissue cells clocks is maintained by the central brain clock � master clock.