Structural Determinants of Workforce Participation after Retirement in Poland

In this paper, we aim to analyse selected structural determinants of workforce participation after retirement in Poland. By structural determinants we mean characteristics of one’s socio-economic position that (a) result from the interplay of social conditions (mechanisms of power, differentiated access to resources) and individual agency, and (b) restrict or facilitate individuals’ choices. We conceptualise workforce participation as engaging in either part- or full-time paid employment despite receiving the old-age pension. Our general hypothesis is that working in older age is not only a matter of motivation or psychological traits but also a complex interplay of structural characteristics, accumulated by individuals during their life course. In the paper, we test a number of hypotheses about the role of specific components of socio-economic status (SES), i.e. occupational prestige, education, and wealth, for workforce participation among retirees. We argue that, in case of retirees, the prestige of the last job before retirement is a more reliable measure of the social position than education. Hence, we conduct a more detailed analysis of the role of occupational prestige for the chances of being employed after retirement. The analysis was based on data gathered in the years 2013–2014 within the sixth wave of the Polish Panel Survey POLPAN (www.polpan.org). We extracted a subsample of retirees from this dataset and used logistic regression to test the hypotheses described above. We found that both occupational prestige of the last job before retirement and educational attainments are strong predictors of being in paid work after retirement, however the impact of occupational prestige varies across the groups with the lowest and higher level of retirement pension. We also found that there are horizontal differences in the occupational structure of the chances for workforce participation after retirement and additionally found that being a farm owner increases the propensity to engage in economic activity after retirement. The paper contributes to the field of studies on the relationship between SES and workforce participation after retirement in line with the cumulative advantage/disadvantage theory and shows that resources that individuals have accumulated during the life course can determine their chances of working after retirement just as individual motivations or organisational characteristics do.     

An assessment of natural concentrations of selected metals in the bone tissues of the femur head

The study was aimed at assessing the natural concentrations of copper, iron, potassium, lead and cadmium in the femur head using regression analysis. The material was collected during the operation of total hip arthroplasty from patients of southern and central Poland suffering from diagnosed coxarthrosis. In total, 197 samples were collected, including 68 samples of spongious bone, 59 samples of cortical bone and 70 samples of cartilage surface. After wet microwave digestion, the metal content in the samples was measured by atomic absorption spectrophotometry. The average concentrations of metals in the femur head were 67.30 microgFe/g, 760.58 microgK/g, 0.07 microgCd/g, 0.81 microgCu/g and 2.76 microgPb/g. A comparison of metal concentrations in bone tissues assessed by regression analysis to the findings of other authors revealed that the technique can be used to assess the natural concentration of elements in tissues and the results may provide a basis for the evaluation of metal concentrations in the human organism.     

Diagnosing double regular systems

We consider the problem of testing sequentially the components of a multi-component system, when the testing of each component is costly. We propose a new testing policy, that can be executed in polynomial time in the input size, and show that it is cost-minimal in the average case sense, for certain double regular systems that include regular (in particular, threshold) systems with identical components. This result generalizes known results for series, parallel, and, more generally, for k-out-of-n systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

From Primary MSC Culture of Adipose Tissue to Immortalized Cell Line Producing Cytokines for Potential Use in Regenerative Medicine Therapy or Immunotherapy

For twenty-five years, attempts have been made to use MSCs in the treatment of various diseases due to their regenerative and immunomodulatory properties. However, the results are not satisfactory. Assuming that MSCs can be replaced in some therapies by the active factors they produce, the immortalized MSCs line was established from human adipose tissue (HATMSC1) to produce conditioned media and test its regenerative potential in vitro in terms of possible clinical application. The production of biologically active factors by primary MSCs was lower compared to the HATMSC1 cell line and several factors were produced only by the cell line. It has been shown that an HATMSC1-conditioned medium increases the proliferation of various cell types, augments the adhesion of cells and improves endothelial cell function. It was found that hypoxia during culture resulted in an augmentation in the pro-angiogenic factors production, such as VEGF, IL-8, Angiogenin and MCP-1. The immunomodulatory factors caused an increase in the production of GM-CSF, IL-5, IL-6, MCP-1, RANTES and IL-8. These data suggest that these factors, produced under different culture conditions, could be used for different medical conditions, such as in regenerative medicine, when an increased concentration of pro-angiogenic factors may be beneficial, or in inflammatory diseases with conditioned media with a high concentration of immunomodulatory factors.     

A Comparative Study on Nickel Binding to Hpn-like Polypeptides from Two Helicobacter pylori Strains

Combined potentiometric titration and isothermal titration calorimetry (ITC) methods were used to study the interactions of nickel(II) ions with the N-terminal fragments and histidine-rich fragments of Hpn-like protein from two Helicobacter pylori strains (11637 and 26695). The ITC measurements were performed at various temperatures and buffers in order to extract proton-independent reaction enthalpies of nickel binding to each of the studied protein fragments. We bring up the problem of ITC results of nickel binding to the Hpn-like protein being not always compatible with those from potentiometry and MS regarding the stoichiometry and affinity. The roles of the ATCUN motif and multiple His and Gln residues in Ni(II) binding are discussed. The results provided the possibility to compare the Ni(II) binding properties between N-terminal and histidine-rich part of Hpn-like protein and between N-terminal parts of two Hpn-like strains, which differ mainly in the number of glutamine residues.     

Physicochemical characteristics,proximate analysis and mineral composition of ostrich meat as influenced by muscle

The influence of muscle on the physicochemical characteristics, proximate analysis, and mineral composition of meat from 10 ostriches (10–12 months old), slaughtered according to commercial abattoir procedures, were evaluated. Muscle had no influence (p > 0.05) on L*-values (32.5), a*-values (11.9), water-holding capacity (11.9%), final pH (pH₂₄) values (6.07), and ash contents (1.12 g/100 g edible meat). However, intramuscular lipid contents varied (p < 0.05) from 0.88 (M. fibularis longus) to 1.44 (M. flexor cruris lateralis) g/100 g edible meat, at a mean value of 1.16 g/100 g edible meat for 10 different muscles. Sodium (34.7 mg/100 g edible meat) and iron (3.14 mg/100 g edible meat) contents, both influenced (p < 0.05) by muscle, possessed substantially lower and higher values, respectively, than values reported for beef and chicken.     

Towards standardizing retinal optical coherence tomography angiography:a review

The visualization and assessment of retinal microvasculature are important in the study,diagnosis,monitoring,and guidance of treatment of ocular and systemic di...