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  • Author: Anna Górska x
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Perception of Women in Top Managerial Positions in Poland

Abstract

Purpose: The aim of the pilot study was to find out whether the perception of candidates for leadership positions differs along with the gender of the candidate in Poland.

Methodology: In order to answer the question, the author has conducted a preliminary experiment on 50 MBA students, which were experienced in recruitment. Two identical CVs were randomly distributed among the participants, with either a male or female version of the CV. Basing on the provided information, respondents were to decide on among others hireability, likeability and offered income to the given candidate.

Findings: The experiment revealed that the female candidate for the CEO position was perceived and evaluated differently than the male candidate. Thus, the experiment indicated that gender inequality may already appear at the phase of recruitment for higher positions.

Originality: The presented study analyzed perceptions of experienced recruiters, which may suggest that such behaviors and patters may be repeated in a non-laboratory environment.

Limitations: A limitation of the pilot study is the low number of participants and therefore further research should be conducted.

Open access
Preliminary characteristics of laminations in recent sediments from lakes Kamenduł and Perty in the Suwałki Landscape Park, northeastern Poland

Abstract

Varved lake sediments are well known archives used for paleoenvironmental reconstructions. They provide continuous, high-resolution and calendar-year chronologies of past environmental changes. From lakes Kamenduł and Perty, located in the Suwałki Landscape Park, short cores of laminated sediments were collected and investigated using microfacies analysis and X-ray fluorescence (XRF) scanning. Sediments of Lake Kamenduł form biogenic (calcite) varves with pale lamina containing precipitated calcite and dark lamina composed of mixed organic and clastic material. There is a visible difference between varves in the lower and the topmost part of the core. The varve thickness and clastic material content decrease upcore. Analysed sediments of Lake Perty also show laminated structures which are biogenic varves composed of calcite laminas interbedded with layers of mixed material and dark laminas containing mostly organic material with some clastic particles. Our study shows that further analysis of sediments from these lakes may provide valuable information about past land use changes in their catchments as well as changes in the water column, i.e. mixing regimes and redox conditions.

Open access
The role of folate receptor and reduced folate carrier polymorphisms in osteoporosis development

Summary

Introduction: Osteoporosis is a chronic metabolic disease with multifactorial etiology. One of possible osteoporosis causes may be impairment of osteoclasts function which leads to increased bone resorption. This may be a result of many metabolic changes. It is believed that changes of folate-methionine metabolism in osteoporosis play an essential role in the etiology of this disease.

Objective: The aim of this study was to examine how polymorphisms of SLC19A1 and FOLR3 genes may play the key role in folate-methionine pathway and influence on the etiology of osteoporosis.

Results: The statistically overrepresentation of mutated GG genotype of FOLR3 (rs11235449) was observed in the control group compared to the osteopenia (34.9% in osteopenia vs. 37.8% in controls, p=0.025, OR=0.61). As to the SLC19A1 (rs3788200) polymorphism we have noted the statistically significant over-representation of wild-type GG genotype (35.8% vs. 26.2%, p=0.046, OR=1.57) and overrepresentation of wild-type G allele (56.9% vs. 50.2%, p=0.061, OR=1.31) in osteopenia group if compared to the controls.

Conclusions: In our study we shown the protective role of mutated GG genotype of FOLR3 (rs11235449) polymorphism to osteopenia progress and possible role of wild-type GG genotype and wild-type G allele of SLC19A1 (rs3788200) polymorphism in osteopenia development.

Open access
The effect of temperature on the efficiency of industrial wastewater nitrification and its (geno)toxicity

Abstract

The paper deals with the problem of the determination of the effects of temperature on the efficiency of the nitrification process of industrial wastewater, as well as its toxicity to the test organisms. The study on nitrification efficiency was performed using wastewater from one of Polish chemical factories. The chemical factory produces nitrogen fertilizers and various chemicals. The investigated wastewater was taken from the influent to the industrial mechanical-biological wastewater treatment plant (WWTP). The WWTP guaranteed high removal efficiency of organic compounds defined as chemical oxygen demand (COD) but periodical failure of nitrification performance was noted in last years of the WWTP operation. The research aim was to establish the cause of recurring failures of nitrification process in the above mentioned WWTP. The tested wastewater was not acutely toxic to activated sludge microorganisms. However, the wastewater was genotoxic to activated sludge microorganisms and the genotoxicity was greater in winter than in spring time. Analysis of almost 3 years’ period of the WWTP operation data and laboratory batch tests showed that activated sludge from the WWTP under study is very sensitive to temperature changes and the nitrification efficiency collapses rapidly under 16°C. Additionally, it was calculated that in order to provide the stable nitrification, in winter period the sludge age (SRT) in the WWTP should be higher than 35 days.

Open access
Detection of antibiotic resistance genes in wastewater treatment plant – molecular and classical approach

Abstract

Antibiotics are a group of substances potentially harmful to the environment. They can play a role in bacterial resistance transfer among pathogenic and non-pathogenic bacteria. In this experiment three representatives of medically important chemotherapeutics, confirmed to be present in high concentrations in wastewater treatment plants with HPLC analysis were used: erythromycin, sulfamethoxazole and trimethoprim. Erythromycin concentration in activated sludge was not higher than 20 ng L−1. N-acetylo-sulfamethoxazole concentration was 3349 ± 719 in winter and 2933 ± 429 ng L−1 in summer. Trimethoprim was present in wastewater at concentrations 400 ± 22 and 364 ± 60 ng L−1, respectively in winter and summer. Due to a wide variety of PCR-detectable resistance mechanisms towards these substances, the most common found in literature was chosen. For erythromycin: erm and mef genes, for sulfamethoxazole: sul1, sul2, sul3 genes, in the case of trimethoprim resistance dhfrA1 and dhfr14 were used in this study. The presence of resistance genes were analyzed in pure strains isolated from activated sludge and in the activated sludge sample itself. The research revealed that the value of minimal inhibitory concentration (MIC) did not correspond with the expected presence of more than one resistance mechanisms. Most of the isolates possessed only one of the genes responsible for a particular chemotherapeutic resistance. It was confirmed that it is possible to monitor the presence of resistance genes directly in activated sludge using PCR. Due to the limited isolates number used in the experiment these results should be regarded as preliminary.

Open access
Impact of Panax ginseng and Ginkgo biloba extracts on expression level of transcriptional factors and xenobiotic-metabolizing cytochrome P450 enzymes

Summary

Introduction: Despite widespread use of Panax ginseng and Ginkgo biloba, the data on the safety as well as herb-drug interactions are very limited. Therefore, we postulate that P. ginseng and G. biloba may modulate the activity and content of cytochrome P450 isozymes involved in the biotransformation of diverse xenobiotic substances. Objective: The aim of our study was to determine the influence of herbal remedies on the expression level of CYP enzymes and transcriptional factors. Methods: Male Wistar rats were given standardized Panax ginseng (30 mg/kg p.o.) or standardized Ginkgo biloba (200 mg/kg p.o.) for 3 and 10 days. The expression in liver tissue was analyzed by realtime PCR method. Results: Our results showed a decrease of CYP3A1 (homologue to human CYP3A4) mRNA level after P. ginseng extract treatment. The CYP2C6 (homologue to human CYP2C9) expression was also reduced. Additionally, after 10 days of the treatment with P. ginseng an increase of CYP1A1 (homologue to human CYP1A1) and CYP1A2 (homologue to human CYP1A2) expression was observed. Moreover, G. biloba extract also caused an increase of expression level for CYP1A1, CYP2C6, CYP3A1 and CYP3A2. Conclusion: Our findings suggest that herbal extracts can modulate the expression of transcriptional factors and CYP enzymes involved in xenobiotic metabolism and chemical carcinogenesis.

Open access
Contribution of non-pollen palynomorphs to reconstructions of land-use changes and lake eutrophication: case study from Lake Jaczno, northeastern Poland

Abstract

Analysis of non-pollen palynomorphs supplemented by pollen analysis, microcharcoal analysis and geochemical data from laminated sediments from Lake Jaczno were used to establish different phases of land-use in the catchment between c.a. AD 1840 and AD 2013. The results show that during the first eighty years the vicinity of the lake was heavily deforested. During this period erosional inputs caused accumulation of abundant fungal spores, indicators of pastures and natural fertilizers (manure) as well as of corroded pollen grains and charcoal. Gradual regeneration of forest cover took place after World War II, when expansion of pioneer trees occurred (Betula, Salix, Carpinus, Populus). At the same time, a considerable increase in the lake trophy was observed, leading to the changes in phytoplankton and macrophyte communities: a decrease in the proportion of Botryococcus and an increase in the Nymphaea alba population. The non-pollen palynomorphs analyses indicate the substantial human impact that caused changing local environmental conditions, compatible with the results based on pollen analysis and geochemical data.

Open access
Comparison of antioxidant activities of fractionated extracts from seedlings and herb of Chelidonium majus L. using DPPH, ABTS and FRAP methods

Summary

Introduction: Our study is a part of a trend of studies on the antioxidative properties of Chelidonium majus extracts or their fractions suggesting that antioxidant activities may depend on total flavonoid and/or alkaloid contents.

Objective: This study focused on the examination of antioxidative activities of full water extract, non-protein fraction and protein fraction of the extract from aerial parts of mature plants and young seedlings.

Methods: Total flavonoid and alkaloid contents were evaluated by spectrometric methods. Quantitative determination of chelidonine, coptisine, sanquinarine, berberine was made by HPLC-UV. The antioxidative activities were evaluated using (1) 2,2-diphenyl-1-picrylhydrazyl (DPPH), (2) 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging and (3) ferric reducing antioxidant power (FRAP) methods.

Results: All concentrations of herb extracts exhibited higher antioxidant capacities than extract from seedlings. Two antioxidant tests (DPPH, FRAP) showed that full water extract from herb had the highest antioxidant activity, while its non-protein fraction and protein fraction showed lower antioxidant activity. It was found that the full water extract from herb contained the highest concentrations of flavonoids and alkaloids when compared with other samples.

Conclusion: Our findings suggest that chelidonine and coptisine especially could be responsible for the observed changes in the extract antioxidant activity, because these alkaloids were determined in the highest concentration in full water extract from herb. It cannot be also excluded that the observed variables values between extracts and their fractions from herb or from seedlings may also be the result of interactions between flavonoids and other chemical compounds.

Open access