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Presença da Justiça nos Provérbios Portugueses e Checos
No full textO texto trata da presença da justiça nos provérbios checos e portugueses.Cílem je porovnat paremiologické zpracování spravedlnosti v portugalských a českých příslovích.The article analysis the presence of justice in Portuguese and Czech proverbs
Finding essentiality feasible: common questions and misinterpretations concerning the "essential-use" concept
No full textThe essential-use concept is a tool that can guide the phase-out of per- and polyfluoroalkyl substances (PFAS) and potentially other substances of concern. This concept is a novel approach to chemicals management that determines whether using substances of concern, such as PFAS, is truly essential for a given functionality. To assess the essentiality of a particular use case, three considerations need to be addressed: (1) the function (chemical, end use and service) that the chemical provides in the use case, (2) whether the function is necessary for health and safety and critical for the functioning of society and (3) if the function is necessary, whether there are viable alternatives for the chemical for this particular use. A few illustrative examples of the three-step process are provided for use cases of PFAS. The essential-use concept takes chemicals management away from a substance-by-substance approach to a group approach. For PFAS and other substances of concern, it offers a more rapid pathway toward effective management or phase-out. Parts of the concept of essential use have already been widely applied in global treaties and international regulations and it has also been recently used by product manufacturers and retailers to phase out substances of concern from supply chains. Herein some of the common questions and misinterpretations regarding the practical application of the essential-use concept are reviewed, and answers and further clarifications are provided
An adverse outcome pathway based in vitro characterization of novel flame retardants-induced hepatic steatosis
Get PDFA wide range of novel replacement flame retardants (nFRs) is consistently detected in increasing concentrations in the environment and human matrices. Evidence suggests that nFRs exposure may be associated with disruption of the endocrine system, which has been linked with the etiology of various metabolic disorders, including nonalcoholic fatty liver disease (NAFLD). NAFLD is a multifactorial disease characterized by the uncontrolled accumulation of fats (lipids) in the hepatocytes and involves multiple-hit pathogenesis, including exposure to occupational and environmental chemicals such as organophosphate flame retardants (OPFRs). In the present study we aimed to investigate the potential mechanisms of the nFRs-induced hepatic steatosis in the human liver cells. In this study, we employed an in vitro bioassay toolbox to assess the key events (KEs) in the proposed adverse outcome pathways (AOP) (s) for hepatic steatosis. We examined nine nFRs using AOP- based in vitro assays measuring KEs such as lipid accumulation, mitochondrial dysfunction, gene expression, and in silico approach to identify the putative molecular initiating events (MIEs). Our findings suggest that several tested OPFRs induced lipid accumulation in human liver cell culture. Tricresyl phosphate (TMPP), triphenyl phosphate (TPHP), tris(1,3-dichloropropyl) phosphate (TDCIPP), and 2-ethylhexyl diphenyl phosphate (EHDPP) induced the highest lipid accumulation by altering the expression of genes encoding hepatic de novo lipogenesis and mitochondrial dysfunction depicted by decreased cellular ATP production. Available in vitro data from ToxCast and in silico molecular docking suggests that pregnane X receptor (PXR) and peroxisome proliferator-activated receptor gamma (PPAR gamma) could be the molecular targets for the tested nFRs. The study identifies several nFRs, such as TMPP and EHDPP, TPHP, and TDCIPP, as potential risk factor for NAFLD and advances our understanding of the mechanisms involved, demonstrating the utility of an AOP-based strategy for screening and prioritizing chemicals and elucidating the molecular mechanisms of toxicity
Unfolding the interaction between microplastics and (trace) elements in water: A critical review
Get PDFPlastic and microplastic pollution is an environmental and societal concern. The interaction of plastic with organic chemicals in the environment has attracted scientific interest. New evidences have highlighted an unexpectedly high affinity of environmental plastics also for metal ions. The degree and typology of plastic ageing (including from mechanical, UV and biological degradations) appear as a pivotal factor determining such an interaction. These earlier evidences recently opened a new research avenue in the plastic pollution area. This review is the first to organize and critically discuss knowledge developed so far. Results from field and laboratory studies of metal accumulation on plastic are presented and the environmental factors most likely to control such an interaction are discussed. On the light of this knowledge, a generalist conceptual model useful for building hypotheses on the mechanisms at stake and directing future studies was elaborated and presented here. Furthermore, all available data on the thermodynamics of the plastic-metal interaction obtained from laboratory experiments are inventoried and discussed here, highlighting methodological and technical challenges that can potentially affect cross-comparability of data and their relevance for environmental settings. Finally, insights and recommendations on experimental approaches and analytical techniques that can help overtaking current limitations and knowledge gaps are proposed
A comparative study of synthetic winged peptides for absolute protein quantification
Get PDFA proper internal standard choice is critical for accurate, precise, and reproducible mass spectrometry-based proteomics assays. Synthetic isotopically labeled (SIL) proteins are currently considered the gold standard. However, they are costly and challenging to obtain. An alternative approach uses SIL peptides or SIL "winged" peptides extended at C- or/and N-terminus with an amino acid sequence or a tag cleaved during enzymatic proteolysis. However, a consensus on the design of a winged peptide for absolute quantification is missing. In this study, we used human serum albumin as a model system to compare the quantitative performance of reference SIL protein with four different designs of SIL winged peptides: (i) commercially available SIL peptides with a proprietary trypsin cleavable tag at C-terminus, (ii) SIL peptides extended with five amino acid residues at C-terminus, (iii) SIL peptides extended with three and (iv) with five amino acid residues at both C- and N-termini. Our results demonstrate properties of various SIL extended peptides designs, e.g., water solubility and efficiency of trypsin enzymatic cleavage with primary influence on quantitative performance. SIL winged peptides extended with three amino acids at both C- and N-termini demonstrated optimal quantitative performance, equivalent to the SIL protein
Raman Microspectroscopic Analysis of Selenium Bioaccumulation by Green Alga Chlorella vulgaris
Get PDFSelenium (Se) is an element with many commercial applications as well as an essential micronutrient. Dietary Se has antioxidant properties and it is known to play a role in cancer prevention. However, the general population often suffers from Se deficiency. Green algae, such as Chlorella vulgaris, cultivated in Se-enriched environment may be used as a food supplement to provide adequate levels of Se. We used Raman microspectroscopy (RS) for fast, reliable, and non-destructive measurement of Se concentration in living algal cells. We employed inductively coupled plasma-mass spectrometry as a reference method to RS and we found a substantial correlation between the Raman signal intensity at 252 cm(-1) and total Se concentration in the studied cells. We used RS to assess the uptake of Se by living and inactivated algae and demonstrated the necessity of active cellular transport for Se accumulation. Additionally, we observed the intracellular Se being transformed into an insoluble elemental form, which we further supported by the energy-dispersive X-ray spectroscopy imaging
Z nesezdaného soužití do manželství : záleží na vzdělanostní homogamii?
Get PDFČlánek se zabývá tím, jaká je asociace mezi vzdělanostní homogamií partnerů v nesezdaných soužitích a přechodem do manželství. Předchozí studie obohacuje o komparativní rozměr a zkoumá, zda a jak se asociace liší v zemích s různými významy kohabitací – v Rakousku, Polsku a Česku. Mimo to se článek zaměřuje na to, zda a jak se asociace mezi tranzicí do manželství a vzdělanostní homogamií v čase mění. Výsledky analýzy dat z první vlny výzkumu Generations and Gender Survey (GGS) ukazují, že na poměru vzdělání partnerů při přechodu do manželství závisí jen v zemích, v nichž se od sebe manželství a kohabitace hodně liší – v Polsku a Česku. Vzdělanostní hypergamie a hypogamie s tranzicí nejsou asociovány stejně. Zatímco v nesezdaných soužitích se vzdělanějším mužem je pravděpodobnost manželství o polovinu nižší než v homogamních soužitích, kohabitace se vzdělanější ženou se od homogamních z hlediska vstupu do manželství významně neliší. V čase se asociace mezi relativním vzděláním partnerů a tranzicí do manželství neměnila.This article examines the association between cohabiting partners’ educational homogamy and transition to marriage. This paper enriches previous studies with its comparative dimension to find out if and how the association differs in countries with different meanings of cohabitation– in Austria, Poland, and the Czech Republic. It also examines if and how the association between the transition to marriage and educational homogamy is changing over time. Using data from the first wave of the Generations and Gender Survey (GGS), the analysis shows that the transition to marriage depends on partners’ relative education only in countries where cohabitation and marriage are two very different institutions– Poland and the Czech Republic. Educational hypergamy and hypogamy are not associated with the transition in the same way. In cohabitations where the man is more educated, the probability of marriage is half that compared to homogamous cohabitations, whereas cohabitations with a more educated woman are not significantly different from homogamous cohabitations. Over time, the association between relative education and the transition to marriage has not changed
Modelling a scale-based strontium isotope baseline for Hungary
Get PDFStrontium isotope analysis has recently proven to be a useful tool to elucidate population movements and subsistence strategies in ecological and archaeological sciences. The interpretation depends on the size, type, availability, and preservation of the sample and the reliability of the produced strontium isotope baseline. However, collecting quantitatively and qualitatively suitable baseline samples is considered a challenging task in archaeological research. To meet these challenges, we introduce an innovative analytical technique, which enables the analysis of small sample sizes from heterogeneous site distribution and environmental settings. This article integrates multivariate environmental modelling and bioarchaeological data of 49 sites to establish the first scale-based differentiation between site-specific and micro-regional strontium isotope baselines with various sample sizes in Hungary. In future mobility studies, this approach will allow distinguishing human and faunal movement ranges on different geographical scales.Strontium isotope analysis has recently proven to be a useful tool to elucidate population movements and subsistence strategies in ecological and archaeological sciences. The interpretation depends on the size, type, availability, and preservation of the sample and the reliability of the produced strontium isotope baseline. However, collecting quantitatively and qualitatively suitable baseline samples is considered a challenging task in archaeological research. To meet these challenges, we introduce an innovative analytical technique, which enables the analysis of small sample sizes from heterogeneous site distribution and environmental settings. This article integrates multivariate environmental modelling and bioarchaeological data of 49 sites to establish the first scale-based differentiation between site-specific and micro-regional strontium isotope baselines with various sample sizes in Hungary. In future mobility studies, this approach will allow distinguishing human and faunal movement ranges on different geographical scales
Permakultura a její inspirace pro oblast společného (inkluzivního) vzdělávání
Get PDFText je kratším zamyšlením nad podněty, které může přinést permakultura do inkluzivního vzdělávání. Rozvíjí myšlenku různorodosti, která se projevuje na úrovni druhů, pohledů a přístupů, nebo funkcí. Tato diverzita přispívá ke stabilitě celku.The text is a shorter reflection on the inspirations that permaculture can bring to inclusive education. It works withthe idea of diversity, which manifests itself at the level of species, views and approaches, or functions. This diversity contributes to the stability of the whole