Relative indexing on the basis of users' profiles

Principles for determining the profile of a system user have been presented. These principles are based on the analysis of co-occurrence of index terms in queries and pertinent documents. Moreover, a procedure for determining index term weights on the basis of user profiles has been introduced. The information value of the index term weights depends on the degree of homogeneity of the system users.     

Job satisfaction and temperament structure of gifted people

This article focuses on the problems of adults who in secondary school were high ability learners. The main point of interest of the research presented here is job satisfaction among gifted people and their temperament structure. The authors are interested whether there exist correlations between the investigated variables both in the entire group of gifted individuals as well as in the subgroup of those gifted in the humanities and in the control group. The research results show that between the group of gifted people and the control group there appear significant differences in vigorousness (VG) and activity (AC). The studied groups differ as to the kind and extent of the fulfilment of expectations concerning professional career. Gifted individuals, in comparison to the control group, are more satisfied with their jobs.     

Teaching the nation: history and nationalism in Polish school history education

This article aims to analyse Polish history teachers’ understanding of the role of teaching history. Drawing on the results of qualitative research conducted in Wroclaw, we argue that teachers see history education through the prism of nationalism. Teachers construct the past in equivocally nationalist terms. They regard nationalist representations of the past as taken for granted. Moreover, teachers reproduce a dominant nationalist discourse by using history to promote the idea of the homogeneous nation. We argue that teachers see their role primarily in terms of imposing the dominant structures of collective memory on the pupils. We also discuss the differences between teachers pertaining to the understanding of the concept of the nation, the way of teaching Polish history and the type of obligation towards the nation. We also demonstrate that teachers do not see a contradiction between history defined as an objective science and history understood as a ‘nationalising’ tool.     

Education policy in Poland: The impact of PISA (and other international studies)

The impact of the PISA study on Polish education policy has been significant, but probably different from any other country. Poland has not experienced the so‐called ‘PISA shock’, but its education system has been benefiting considerably from PISA. For experts and policy makers, it has been a useful and reliable instrument that has made it possible to measure the effects of consecutive reforms of the school education system. Moreover, PISA and other international studies have influenced the perception of education policy in Poland. The latter has shifted from an ideology‐driven, centralised policy to an evidence‐informed policy, developed with the involvement of multiple stakeholders, although this has mostly affected the thinking of experts and policy makers rather than the general public. The new government (in power from 2015), following public opinion polls, has reversed most of the previous education reforms, eliminating lower secondary schools introduced in 1999.     

Dynamics of a periodically driven chain of coupled nonlinear oscillators

A 1D chain of coupled oscillators is considered, including the Duffing-type nonlinearity, viscous damping, and kinematic harmonic excitation. The equations of motion are presented in a non-dimensional form. The approximate equations for the vibrational amplitudes and phases are derived by means of the classical averaging method. A simple analysis of the resulting equations allows one to determine the conditions for the two basic synchronous steady-states of the system: the in-phase and anti-phase motions. The relations between the required excitation frequency and the natural frequencies of the abbreviated (linear) system are discussed. The validity of these predictions is examined by a series of numerical experiments. The effect of the model parameters on the rate of synchronization is analyzed. For the purpose of systematic numerical studies, the cross-correlation of time-series is used as a measure of the phase adjustment between particular oscillators. Finally, some essential issues that arise in case of the mechanical system with dry friction are indicated.     

Overweight and obesity versus concentrations of VEGF-A,sVEGFR-1, and sVEGFR-2 in plasma of patients with lower limb chronic ischemia

Objective

Being overweight or obese comprises a significant risk factor for atherosclerosis. Fat tissue also generates factors stimulating angiogenesis, the process by which new blood vessels form. The purpose of this paper is to assess concentrations of the vascular endothelial growth factor A (VEGF-A) and its soluble type-1 and type-2 receptors (sVEGFR-1 and sVEGFR-2) in plasma of patients with peripheral arterial disease (PAD) depending on the level of nutrition according to body mass index (BMI).

Methods

The study group included patients suffering from symptomatic PAD (n=46) in Fontaine classes IIa–IV without any history of neoplastic disease and who have a normal BMI (n=15), are overweight (n=21) or are obese (n=10). The control group (n=30) consisted of healthy non-smoking volunteers who were neither overweight nor obese. Venous blood plasma samples were collected from both groups at rest in the morning to determine plasma concentrations of VEGF-A, sVEGFR-1, and sVEGFR-2 using the enzymelinked immunosorbent assay (ELISA) method.

Results

The group of patients with PAD co-existent with being overweight or obese tended to have higher mean concentration levels of VEGF-A and sVEGFR-2 when compared with patients suffering from PAD with normal BMI. A statistically significant positive correlation was obtained between BMI and average plasma concentrations of sVEGFR-2 (R=0.37, P=0.0103). However, no significant correlation was noticed between BMI and VEGF-A or sVEGFR-1 concentrations.

Conclusions

A positive correlation determined between the level of antiangiogenic factor and BMI value may be indicative of the linearly growing prevalence of some antiangiogenic factors in patients with metabolic disorders, which may be one of numerous factors contributing to incomplete efficiency of collateral circulation development in patients with PAD.

     

Propolis modulates vitronectin, laminin, and heparan sulfate/heparin expression during experimental burn healing

Objective

This study was aimed at assessing the dynamics of vitronectin (VN), laminin (LN), and heparan sulfate/heparin (HS/HP) content changes during experimental burn healing.

Methods

VN, LN, and HS/HP were isolated and purified from normal and injured skin of domestic pigs, on the 3rd, 5th, 10th, 15th, and 21st days following thermal damage. The wounds were treated with apitherapeutic agent (propolis), silver sulfadiazine (SSD), physiological salt solution, and propolis vehicle. VN and LN were quantified using an immunoenzymatic assay and HS/HP was estimated by densitometric analysis.

Results

Propolis treatment stimulated significant increases in VN, LN, and HS/HP contents during the initial phase of study, followed by a reduction in the estimated extracellular matrix molecules. Similar patterns, although less extreme, were observed after treatment with SSD.

Conclusions

The beneficial effects of propolis on experimental wounds make it a potential apitherapeutic agent in topical burn management.