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Łukasz Kaczmarek

Resiliency, stress appraisal, positive affect and cardiovascular activity

In accordance with the undoing hypothesis (Fredrickson, Levenson, 1998), evoked positive affect speeds up the cardiovascular system recovery in a stressful situation. An attempt was made to replicate this finding in an experimental study. Individuals characterized by high resiliency levels are capable of more efficient utilization of positive emotions in a stressful situation. Since in earlier research no relationship had been found between resiliency and a tendency to appraise stress as a challenge, this study investigated a possible mediating function of a more specific dimension of cognitive appraisal, i.e. that in terms of activity-oriented challenge appraisal (Włodarczyk, Wrześniewski, 2005). The study shows that evoked positive affect does not lead to a faster recovery. However, highly resilient individuals turned out to achieve higher levels of positive affect in a stressful situation; this effect was mediated by challenge-activity appraisals.

Open access

Lukasz Kaczmarek, Maja Stanko-Kaczmarek and Stephan Dombrowski

Adaptation and Validation of the Steen Happiness Index into Polish

Authentic happiness is a construct comprising 3 factors: pleasure, engagement, and meaning (Seligman, Parks, & Steen, 2005). Three studies involving altogether 464 participants adapted and validated the authentic happiness measure Steen Happiness Index (SHI; Seligman, Steen, Park, & Peterson, 2005) into Polish. In Study 1 the Polish version of the scale was developed and its convergence with the original SHI was assessed using bilingual response method, r = .98, p < .001. In Study 2 cluster analysis confirmed the theoretical profiles of happiness, testing the proposed 3-factor structure of the scale, χ2 (116) = 180.62, GFI = .95, CFI=.97, SRMR = .04, RMSEA = .04, RMSEA 90% CI [.25 - .45]. Test-retest reliability (Study 3) yielded satisfactory results, rtt = .87, p < .01. This is the first study providing empirical support for the structural validity of the authentic happiness construct. It also shows the cross-cultural generality of the construct. We discuss some practical applications of the scale.

Open access

Łukasz Kaczmarek and Paweł Dobak

Abstract

Localised landslide activity has been observed in the area of the plateau slope analysed, in the vicinity of the planned Warsaw Southern Ring Road. Using calculation models quantitative and qualitative evaluations of the impact of natural and anthropogenic load factors on slope stability (and hence, safety) are made. The present paper defines six stages of slope stability analysis, leading to an indication of optimum slope design in relation to the development planned. The proposed procedure produces a ranking of factors that affect slope stability. In the engineering geological conditions under consideration, the greatest factors impacting degradation and failure of slope stability are changes in soil strength due to local, periodic yielding and the presence of dynamic loads generated by intensification of road traffic. Calculation models were used to assess the impact of destabilisation factors and to obtain mutual equivalence with 3D-visualisation relations. Based on this methodology, various scenarios dedicated to specific engineering geological conditions can be developed and rapid stability evaluations of changing slope loads can be performed.

Open access

Łukasz Kaczmarek and Paweł Dobak

Abstract

Soil creep deformation refers to phenomena which take place in many areas and research in this field of science is rich and constantly developing. The article presents an analysis of the literature on soil creep phenomena. In light of the complexity of the issues involved and the wide variety of perspectives taken, this attempt at systematization seeks to provide a reliable review of current theories and practical approaches concerning creep deformation. The paper deals with subjects such as definition of creep, creep genesis, basic description of soil creep dynamics deformation, estimation of creep capabilities, various fields of creep occurrence, and an introduction to creep modeling. Furthermore, based on this analysis, a new direction for research is proposed.

Open access

Michał Ziarko, Łukasz Kaczmarek and Ewa Mojs

Mediating role of coping styles in the relationship between anxiety and health behaviors of obese adolescents

Obesity is one of the major health problems in adolescents. Health-detrimental lifestyle (i.e. lack of physical activity, inappropriate nutrition) as well as maladaptive styles of coping with stress are regarded as belonging among determinants of obesity. The aim of the study was to establish factors mediating between anxiety and diet-related health behaviors. Participants in the study were 113 adolescents with obesity whose body weight was over 97th centile. They were examined using a set of self-report questionnaires to measure anxiety, coping styles and health behaviors. Emotion-focused coping and seeking social contacts (social diversion) were found to act as mediators between adolescents' trait anxiety and their health behaviors. The findings suggest that to enhance obese adolescents' health-promoting behaviors appropriate conditions should be ensured that would not only enable them to express their emotions, but also promote their socializing with peers.

Open access

Łukasz Kaczmarek, Bartłomiej Gołdyn, Michał Czyż and Łukasz Michalczyk

First records of Isohypsibius pushkini Tumanov, 2003 (Tardigrada, Eutardigrada, Hypsibiidae) from Poland

First records of Isohypsibius pushkini from small ponds in western Poland are described. So far, these are the only records of this species apart from its type locality in Russia. We present some remarks on the ecology of the species, as well. Moreover, we present the first ever microphotographs of I. pushkini.

Open access

Łukasz Dominik Kaczmarek, Yufeng Zhao, Heinz Konietzky, Tomasz Wejrzanowski and Michał Maksimczuk

Abstract

The study employs numerical calculations in the characterization of reservoir sandstone samples based on high-resolution X-ray computed microtomography. The major goals were to determine porosity through pore size distribution, permeability characterization through pressure field, and structure impact on rock strength by simulation of a uniaxial compression test. Two Miocene samples were taken from well S-3, located in the eastern part of the Carpathian Foredeep. Due to the relation between sample size and image resolution, two X-ray irradiation series with two different sample sizes were performed. In the first approach, the voxel side was 27 μm and in the second it was up to 2 μm. Two samples from different depths have been studied here. Sample 1 has petrophysical features of conventional reservoir deposits, in contrast to sample 2. The approximate grain size of sample 1 is in the range 0.1-1.0 mm, whereas for sample 2 it is 0.01-0.1 mm with clear sedimentation lamination and heterogenic structure. The porosity, as determined by μCT, of sample 1 is twice (10.3%) that of sample 2 (5.3%). The equivalent diameter of a majority of pores is less than 0.027 mm and their pore size distribution is unimodal right-hand asymmetrical in the case of both samples. In relation to numerical permeability tests, the flow paths are in the few privileged directions where the pressure is uniformly decreasing. Nevertheless, there are visible connections in sample 1, as is confirmed by the homogenous distribution of particles in the pore space of the sample and demonstrated in the particle flow simulations. The estimated permeability of the first sample is approximately four times higher than that of the second one. The uniaxial compression test demonstrated the huge impact of even minimal heterogeneity of samples in terms of micropores: 4-5 times loss of strength compared to the undisturbed sample. The procedure presented shows the promising combination of microstructural analysis and numerical simulations. More specific calculations of lab tests with analysis of variable boundary conditions should be performed in the future.

Open access

Łukasz Kaczmarek, Anna Kozłowska, Michał Maksimczuk and Tomasz Wejrzanowski

Abstract

This paper presents for the first time X-ray computed microtomography (μCT) analysis as a technique for Silurian graptolite detection in rocks. The samples come from the Jantar Bituminous Claystones Member of the Opalino core, Baltic Basin, northern Poland. Images were obtained with spatial resolution of 25 μm, which enabled the authors to create a 3-D visualization and to calculate the ratio of fissure and graptolite volume to the total sample volume. A set of μCT slices was used to create a 3-D reconstruction of graptolite geometry. These μCT slices were processed to obtain a clearly visible image and the volume ratio. A copper X-ray source filter was used during exposure to reduce radiograph artifacts. Visualization of graptolite tubaria (rhabdosomes) enabled Demirastrites simulans to be identified. Numerical models of graptolites reveal promising applications for paleontological research and thus for the recognition and characterization of reservoir rocks.

Open access

Łukasz Dominik Kaczmarek, Paweł Józef Dobak and Kamil Kiełbasiński

Abstract

The study concerns soil creep deformation in multistage triaxial stress tests under drained conditions. High resolution X-ray computed microtomography (XμCT) was involved in structure recognition before and after triaxial tests. Undisturbed Neogene clay samples, which are widespread in central Poland, were used in this study. XμCT was used to identify representative sample series and informed the detection and rejection of unreliable ones. Maximum deviatoric stress for in situ stress confining condition was equal 95.1 kPa. This result helped in the design of further multistage investigations. The study identified the rheological strain course, which can be broken down into three characterizations: decreasing creep strain rate, transitional constant creep velocity, and accelerating creep deformation. The study found that due to multistage creep loading, the samples were strengthened. Furthermore, there is a visibly “brittle” character of failure, which may be the consequence of the microstructure transformation as a function of time as well as collapse of voids. Due to the glacial tectonic history of the analyzed samples, the reactivation of microcracks might also serve as an explanation. The number of the various sizes of shear planes after failure is confirmed by XμCT overexposure.

Open access

Łukasz D. Kaczmarek, Piotr Haładziński, Lech Kaczmarek, Błażej Bączkowski, Michał Ziarko and Stephan U. Dombrowski

A comprehensive understanding of participants’ motives to complete web-based surveys has the potential to improve data quality. In this study we tested the construct validity of a scale developed to measure motivation to participate in webbased surveys. We expected that 7 different motivations observed in our previous study will form a 3-factor structure, as predicted by Self-Determination Theory. This web-based questionnaire study comprised 257 participants completing the Voluntary Participation in Online Studies Scale. Their responses to 21 items underwent a principal component analysis and confi rmatory factor analysis. As we expected, three factors were identifi ed: intrinsic motivation, extrinsic motivation and amotivation. In line with Self-Determination Theory there are three distinct groups of motives among web-surveys participants with amotivation as an understudied motivational state. We discuss the results suggesting which types of motivation might lead to higher quality of data with an emphasis on possible negative effects of amotivation.