Maria Curie-Sklodowska University in Lublin
Recent publications
The specific physico-chemical properties of chitosan (Ch), a biopolymer isolated from chitin, and its impact on the stability of colloidal dispersity have focused the interest of science and industry. However, in some cases chitosan alone is not enough to provide high stability to dispersions, making it necessary to add surfactant to the chitosan/oxide system, leading to superior stabilizing properties due to the association of polymer and surfactant molecules to form complexes that can modify the ability of bare chitosan for adsorbing on colloidal materials. This study explores the interactions between chitosan and alumina in the presence of three different anionic surfactants: the hydrocarbon SDS (sodium dodecyl sulfate), the fluorocarbon FS-91 (Capstone® FS-91), and the silicone A-Si (Silphos A-100). Different analytical methods evidenced chitosan adsorption on the alumina surface, forming hybrid organic-inorganic materials. This process can be enhanced by adding surfactant, with SDS leading to a strong increase of chitosan adsorption. Elemental mapping and scanning electron microscope imaging have provided a confirmation of the co-adsorption of polymer and surfactant on the alumina surface. The latter emerges as a very important finding because the results have shown that small quantities of surfactant (as low as 0.002% v/v) can strongly influence the adsorption and stability of multicomponent colloidal systems. This allows decreasing the chitosan amount required for the enhancement of the colloidal stability in relation to dispersions without added surfactants, providing the basis for reducing the production costs of colloidal dispersion, which opens new opportunities to chemical industry.
This study concerns the fabrication of CTAB- and N,N-dimethyltetradecylamine-grafted zirconia and evaluation of their ability to adsorb vanadium ions. The effectiveness of ZrO2 functionalization and the different nature of the modifiers used were confirmed by differences in the porosity (ZrO2: SBET = 347 m²/g; ZrO2-CTAB: SBET = 375 m²/g, ZrO2–NH⁺: SBET = 155 m²/g), types of functional groups, and isoelectric points (the ZrO2 and CTAB-modified samples have IEPs = 3.8 and 3.9, ZrO2–NH⁺ has IEP = 7.1) of the prepared adsorbents. The designed materials were tested in batch adsorption experiments involving the removal of vanadium ions from model wastewaters at various process parameters, among which pH proved to be the most important. Based on equilibrium and kinetic evaluations, it was proved that the sorption of V(V) ions followed pseudo-second-order and intraparticle diffusion models, and the data were better fitted to the Langmuir model, suggesting the following order of the sorbents in terms of favorability for V(V) ion adsorption: ZrO2–NH⁺ > ZrO2 > ZrO2-CTAB. The estimated maximum monolayer capacity of ZrO2–NH⁺ for V(V) (87.72 mg/g) was the highest among the tested materials. Additionally, it was confirmed that adsorption of V(V) ions onto synthesized materials is a heterogeneous, exothermic, and spontaneous reaction, as evidenced by the calculated values of thermodynamic parameters. The key goals included the transfer of experimental findings obtained using model solutions to the adsorption of V(V) ions from solutions arising from the leaching process of spent catalysts. The highest adsorption efficiencies of 70.8% and 47.5% were recorded for the ZrO2–NH⁺ material in acidic solution; this may be related to the protonization of –NH⁺ groups, which favors the sorption of V(V) ions. Based on desorption tests as well as the results of infrared and X-ray photoelectron spectroscopy, irrespective of the process conditions, the physical nature of the adsorbent/adsorbate interaction was confirmed.
In the last years, there is great progress in the field of studies on the thermal transformation of wastes into valuable materials such as biochar. High-temperature processes, however, are connected with the formation of polycyclic aromatic hydrocarbons (PAHs) with confirmed toxicity. However, during pyrolysis, some derivatives containing oxygen, nitrogen, or sulfur can also be formed. Their toxicity is expected to be higher than parent PAHs. However, the key parameter in the agricultural application of carbonaceous materials is PAHs’ bioavailability. The aim of the presented studies was the determination of the effect of various feedstock (wheat straw (Triticum L.), willow (Salix viminalis), sunflower, residues from softwood and hardwood, sewage sludges, and residues from biogas production) on the formation of PAHs and their derivatives (O-, N-PAHs) in biochar and their bioavailability. The results indicated that the content of total and bioavailable PAHs in obtained biochar was rather low. The concentration of total PAHs in plant-derived biochar reached 57 ± 3 ng g⁻¹ - 181 ± 8 ng g⁻¹, whereas sewage sludge-derived biochar contained from 121 ± 6 ng g⁻¹ to 188 ± 9 ng g⁻¹ of PAHs. The highest concentration of PAHs was noted in biochar obtained from residues from biochar production – up to 202 ± 9 ng g⁻¹. The total concentration of bioavailable PAHs was lower and reached 2–4.45 ng L⁻¹ for plant-derived biochar, 3–40 ng L⁻¹ for sewage sludge-derived biochar. The highest content of bioavailable PAHs was noted in biochar obtained from residues from biogas production: 9–42 ng L⁻¹ indicating that increased attention should be paid to using this type of biochar. Among PAHs derivatives, nitronaphthalene, 1-methyl-5-nitronaphthalene, 1-methyl-6-nitronaphthalene, 9,10-anthracenedione, 4H-cyclopenta(def)phenanthrene, nitropyrene were determined at various levels and their concentrations were from below the limit of detection (LOD) to 28 ng L⁻¹ for plant-derived biochar, 3–16 ng L⁻¹ for biochar obtained from residues from biogas production, and 5–45 ng L⁻¹ for sewage sludge-derived biochar. The content of bioavailable PAHs derivatives was, generally, one order of magnitude lower than parent PAHs derivatives, and reached from below LOD up to almost 1 ng L⁻¹ for plant-derived biochar, from 0.5 to 2 ng L⁻¹ for biochar obtained from residues from biogas production, and from 0.2 to almost 5 ng L⁻¹ for sewage sludge-derived biochar confirming the safety of agricultural usage of biochar.
The ejection of a mixture of solid (soil) and liquid (water) phases is one of the aspects of the energy dissipation of the impacting drop during the soil splash phenomenon. All calculations to date have only been taking into account the ejection of solid phase material and were based on significant simplifications of the measured quantities. Therefore, the aim of the study was an improved calculation of the falling drop energy transferred to the ejected material, while considering that such material was a mixture of solid soil particles and water droplets and therefore, “two-phase”. Experimental variants included combinations of soils with different textures and initial moisture contents as well as various falling water-drop energies. Two complementary methods of i) splash cup measurements and ii) image analysis based on high-speed cameras were used for the calculation of quantities i.e. the number of ejected particles, their mass, and their ejection velocity. Based on the obtained results, it was stated that the kinetic energy of ejected particles, expressed as a percentage of falling drop energy, ranged from 1 % to 14 %. This percentage depended strongly on soil texture as well as initial moisture content. The highest values were obtained for soil with the largest amount of sand fraction and the lowest for the soil with the largest amount of finer fractions. All tested soils showed a trend of a higher drop energy transferred to the splashed particles with increasing initial soil moisture content. Taking into account the varied energy of the falling drop variants, the amount of energy transferred to ejected particles was constant.
In the chemistry of organophosphorus compounds, chirality is a well‐known and broadly discussed phenomenon. This feature of organophosphorus compounds is not only of purely academic interest. It also presents a high practical value as many organophosphorus compounds with a chirality center either at the phosphorus atom or in a side chain can be prepared and applied in various fields of chemistry, including the synthesis of pharmaceutically active ingredients, ligands for asymmetric catalysis, organocatalysts, components for material chemistry, etc. The impact of chiral organophosphorus compounds on the development of different branches of chemistry has been very strong. The recent literature data confirm this trend to be still developing in the forthcoming years.
The synthesis and characterization of polymeric cross-linked composites derived from bisphenol A glycerolate diacrylate (BPA.GDA) and N-vinyl-2–2pyrrolidone (NVP) are presented. Commercially available kraft lignin with different weight % (0, 5, and 20) was applied as an environmentally friendly filler. The composites were made by bulk polymerization using a photoinitiator (2-dimethoxy-2-phenylacetophenone) in special glass molds and cut into 10 mm × 10 mm fragments for testing. The chemical structures of the composites were confirmed by means of ATR-FTIR spectroscopy. Polymers modified with the addition of lignin were introduced into cultures of three species of white rot fungi: Cerrena unicolor, Pycnoporus sanquineus, and Abortiporus biennis. The biochemical and profilometric analyses showed clear changes both in the course of selected metabolic processes in the fungal cells and in the structure of the biomaterials. Clear changes in the activity of such enzymes as laccase, β-glucosidase, or acid proteases caused by the selected polymers were observed in the culture fluids.
Different doses of treosulfan plus fludarabine have shown advantage over reduced intensity regimens. However, data comparing higher doses of treosulfan to myeloablative busulfan are limited. Thus, we compared outcomes between FT14 (fludarabine 150/160 mg/m2 and treosulfan 42 g/m2, or FT14) over FB4 (fludarabine 150/160 mg/m2 and busulfan 12.8 mg/kg). We retrospectively studied patients from European Society for Blood and Marrow Transplantation registry: a) adults diagnosed with acute myeloid leukemia (AML), b) recipients of first allogeneic hematopoietic stem cell transplantation (HSCT) from unrelated or sibling donor (2010–2020), c) HSCT at first or second complete remission, d) conditioning with FT14 or FB4. FT14 recipients (n = 678) were older, with higher rates of secondary AML, unrelated donors, peripheral blood grafts, and adverse cytogenetics, but lower percentage of female donor to male recipient compared to FB4 (n = 2025). Analysis was stratified on age. In patients aged < 55 years, FT14 was associated with higher relapse incidence (RI) and lower Leukemia-Free Survival (LFS). In patients aged≥55 years, acute GVHD CI was higher in FB4, without significant differences in other outcomes. Although FT14 has been used for higher-risk HSCT patients, our large real-world multicenter study suggests that FB4 is associated with better outcomes compared to FT14 in younger patients.
In the wide range of products containing hemp ingredients, cannabinoid oils are the most popular. They have gained popularity not only among people struggling with various health ailments, but also those who search for a neutral way of taking care of their body and mind. The antioxidant activities of cannabinoid oils differing in the type of their main cannabinoid [i.e., Cannabigerol (CBG), Cannabidiol (CBD), Δ9-Tetrahydrocannabinol (Δ9-THC), Cannabigerolic acid (CBGA), Cannabidiolic acid (CBDA) or Δ9-Tetrahydrocannabinolic acid (Δ9-THCA)] are compared and discussed in the paper. The oils with the same concentration of their main cannabinoid but prepared in different ways were applied in the experiments. Following the presented results, cannabinoid oils obtained from the plant extracts are characterized by evidently greater antioxidant activity than those prepared from pure cannabinoids. The essential difference in the antioxidant activity of the oils containing the neutral or acidic form of a given cannabinoid is observed only in the case of THC and THCA oils.
This article, through the use of a case study focused on Frederick W. Taylor, shows how the issue of mastery with people engaged in their work can be a significant factor connecting a person’s work and leisure worlds. As a labourer, then gang boss in a steel mill, Taylor “developed” stratagems piecemeal to solve the problems that he faced in working in industrial factories. The issue of time became fundamental in his thinking and led to his becoming a manager and “The father of Scientific Work Management”. Concurrently his leisure pursuits grew from nightly runs to becoming a champion tennis player, to becoming an Olympic golfer, to fashioning his own tennis racket and golf clubs while experimenting over years with many varieties of seeds in an attempt to create “the one best” type of grass for putting greens. His work life never stopped. There is not time and then spare time, J. B. Priestley wrote and Taylor became adept at “Managing all his Time”. His life experience may be seen as an illustrative case of how work (of an engaged nature) and what mindset one comes to embrace at work can be replicated in one’s leisure time physical activities.
Despite the fact that urban areas have existed for millennia, no single, universal, supranational, and fully accepted definition of a city/town has been developed to date. The aim of this article is to review the criteria for identifying cities/towns in the world and their spatial differentiation. 233 territorial entities that are sovereign states or territories belonging to other states were surveyed. The analysis was based on a query from a list provided by the Department of Economic and Social Affairs of the United Nations Population Division, which contains the definitions of cities/towns adopted by individual countries or territories when collecting data in censuses. The research carried out shows that single-or multicriteria definitions, referring to quantitative or (and) qualitative elements from the group of legal-administrative, demographic, infrastructural-spatial, and functional criteria, are most often used to distinguish cities/towns from villages. More than half of the surveyed territorial entities use only one criterion mentioned, and this is usually a legal-administrative criterion or a demographic criterion. In the process of identifying cities/towns, just over two-fifths of the surveyed entities apply a minimum population threshold (as the only or one of many criteria), set most often at 2,000 or 5,000 inhabitants. East Africa is the most diverse region in the world in terms of the criteria adopted, while Central Asia, Australia, and New Zealand are the least. ----------------------------------------------------------------------------------------- Pomimo tego, że skupiska miejskie istnieją od tysiącleci, do dziś nie udało się wypracować jednej, powszechnej, uniwersalnej, ponadnarodowej i w pełni akceptowanej definicji miasta. Celem artykułu jest przegląd kryteriów identyfikacji miast na świecie i ich przestrzennego zróżnicowania. Badaniu poddano 233 jednostki będące suwerennymi państwami lub terytoriami przynależącymi do innych państw. Analiza została oparta na kwe-rendzie listy udostępnionej przez Wydział Ludności Departamentu Spraw Gospodarczych i Społecznych organizacji Narodów Zjednoczonych, zawierającej definicje miast przyjmowane przez poszczególne państwa lub terytoria przy zbieraniu danych w spisach powszechnych. Z przeprowadzonych badań wynika, że do odróżnienia miasta od wsi najczęściej wykorzystuje się jednokryterialne lub złożone definicje, odwołujące się do ilościowych lub (i) jakościowych elementów z grupy kryteriów prawno-administracyjnych, demograficznych, infrastrukturalno--przestrzennych i funkcjonalnych. Ponad połowa badanych jednostek wykorzystuje tylko jedno wymienione kryterium, przy czym jest to zwykle kryterium prawno-administracyjne lub kryterium demograficzne. W procesie identyfikacji skupisk miejskich nieco ponad dwie piąte badanych jednostek stosuje minimalny próg ludnościowy (jako jedyne lub jedno z wielu kryteriów), ustalony najczęściej na poziomie 2000 lub 5000 mieszkańców. Najbardziej zróżnicowanym regionem na świecie pod względem przyjmowanych kryteriów jest Afryka Wschodnia, najmniej zaś Azja Środkowa oraz Australia i Nowa Zelandia.
Carbon adsorbents were obtained by carbonization of polyimide polymer with and without the presence of phosphoric acid at temperatures in the range of 400–1000 °C. Carbons produced in the presence of phosphoric acid have been demonstrated to contain up to 13.2% phosphorus. The structure of phosphorus-containing compounds was investigated by XPS and 31P MAS NMR methods. Deconvolution of the P 2p peak with variable binding energy showed the presence of only phosphates/polyphosphates. However, a low value of the O/P ratio is an indirect indication of the possible presence of phosphonates. A 31P MAS NMR study revealed the existence of several kinds of phosphates as well as a minor quantity (1–9%) of phosphonates. All discovered phosphorus-containing compounds are acidic and therefore give carbon the ability to absorb metal cations. The study of copper ion adsorption demonstrated that phosphorus-containing carbon shows a significant adsorption capability even in extremely acidic conditions. At pH 3–6, phosphorus-containing carbon may completely remove copper from the aqueous solution. Phosphorus-containing carbon has a higher adsorption capacity for copper ions than ion exchange resins with carboxyl or sulfo groups.
Hypertension and lipid disorders are two of the main cardiovascular risk factors. Both risk factors - if detected early enough - can be controlled and treated with modern, effective drugs, devoid of significant side effects, available in four countries as different as Italy, Spain, Poland, and Uzbekistan. The aim herein, was to develop this TIMES TO ACT: consensus to raise the awareness of the available options of the modern and intensified dyslipidemia and arterial hypertension treatments. The subsequent paragraphs involves consensus and discussion of the deleterious effects of COVID-19 in the cardiovascular field, the high prevalence of hypertension and lipid disorders in our countries and the most important reasons for poor control of these two factors. Subsequently proposed, are currently the most efficient and safe therapeutic options in treating dyslipidemia and arterial hypertension, focusing on the benefits of single-pill combination (SPCs) in both conditions. An accelerated algorithm is proposed to start the treatment with a PCSK9 inhibitor, if the target low-density-lipoprotein values have not been reached. As most patients with hypertension and lipid disorders present with multiple comorbidities, discussed are the possibilities of using new SPCs, combining modern drugs from different therapeutic groups, which mode of action does not confirm the "class effect". We believe our consensus strongly advocates the need to search for patients with cardiovascular risk factors and intensify their lipid-lowering and antihypertensive treatment based on SPCs will improve the control of these two basic cardiovascular risk factors in Italy, Spain, Poland and Uzbekistan.
The article deals with the issue of spatial plans at the local level. The aims of this paper are (1) extracting the characteristics of local spatial plans that can be compared more broadly (2) identifying, on this basis, the role of spatial plans at the local level in the countries of Central and Eastern Europe (CEE). In achieving these aims, the authors have critically examined spatial plans and their performance, as well as the planning systems they belong to. Hence, they have investigated the types of local plans in each country, their legal features, and the layout of their content. This examination has revealed a host of problems in the workings of the CEE planning systems. The article highlights those spatial planning issues that could be the subject of more in-depth international comparisons. The study provides additional evidence that in countries where spatial plans are legislated, there are more (mutually differentiated) legal problems in their application. Such problems have been analyzed. Besides procedural problems, discrepancies between the contents of different types of plans (e.g., general plans and detailed plans) are very often a problem. The paper also proposes a novel method for detailed comparisons of selected aspects of spatial plans. It can be applied to a large number of countries and also to other aspects of spatial planning. Last but not least, the paper emphasizes the need for a detailed multi-stage consultation of each aspect to be compared.
Introduction: This systematic review and meta-analysis of 19 studies, was conducted to evaluate the role of copeptin in diagnosis and outcome prediction in HF patients. Materials and Methods: A systematic literature search for clinical trials reporting copeptin levels in HF patients was performed using EMBASE, PubMed, Cochrane Register of Controlled Trials, and Google Scholar. Articles from databases published by January 2nd, 2022, that met the selection criteria were retrieved and reviewed. The random effects model was used for analyses. Results: Pooled analysis found higher mean copeptin levels in HF vs. non-HF populations (43.6 ± 46.4 vs. 21.4 ± 21.4; MD= 20.48; 95%CI: 9.22 to 31.74; p < 0.001). Pooled analysis of copeptin concentrations stratified by ejection fraction showed higher concentrations in HFrEF vs. HFpEF (17.4 ± 7.1 vs. 10.1 ± 5.5; MD= -4.69; 95%CI: -7.58 to -1.81; p = 0.001). Copeptin level was higher in patients with mortality/acute HF-related hospitalization vs. stable patients (31.3 ± 23.7 vs. 20.4 ± 12.8; MD= -13.06; 95%CI: -25.28 to -0.84; p = 0.04). Higher copeptin concentrations were associated with mortality and observed in all follow-up periods (p <0.05). Discussion and Conclusions: Present meta-analysis showed that elevated copeptin plasma concentrations observed in HF patients are associated with increased risk of all-cause mortality, thus copeptin may serve as predictor of outcome in HF.
Vitamin K is one of the many health-promoting substances whose impact on the human body has been underestimated until recently. However, recently published research results have changed this situation, prompting some researchers to consider it a new panacea for diseases of old age. The result is a significant increase in interest in the accurate analysis of vitamin K in various types of samples, ranging from food, through dietary supplements, to biological matrices and clinical trials, both observational and interventional. This review summarizes the current state of knowledge about the proven and speculated biological activity of vitamin K and its importance for the world’s aging societies, including the methods used for its isolation and analysis in various matrices types. Of all the analytical methods, the currently preferred methods of choice for the direct analysis of vitamin K are chromatographic methods, in particular liquid chromatography-tandem mass spectrometry. This technique, despite its sensitivity and selectivity, requires an appropriate stage of sample preparation. As there is still room for improvement in the efficiency of these methods, especially at the sample preparation stage, this review shows the directions that need to be taken to make these methods faster, more efficient and more environmentally friendly.
Cereals are often contaminated with fumonisins, which are the toxic byproducts of mold. The aim of the study was to determine the effect of maternal exposure to fumonisins on the development and the liver function of the offspring at weaning. Two doses of fumonisins (60 and 90 mg/kg b.w.) were tested. The changes in the basal blood morphology, the biochemical parameters, the absolute and relative weights of the vital organs, and the changes in the cardiac and biceps brachii muscle histology were studied. The liver damage was assessed by evaluating the liver morphology and the common clinical liver panel. Maternal fumonisin intoxication caused a decrease in the body weight at birth and an increase in the heart, liver, kidney, lungs, ovaries, and testes weights. The cytokines and hormones, as well as the red blood cell counts and hemoglobin levels, were elevated in a dose-dependent manner following the exposure to fumonisins. Maternal exposure caused degenerative morphological and structural changes in the liver, as well as inflammation in the striated muscles, such as the heart and biceps brachii, and disproportionate development of the rat offspring in a dose-dependent manner. Moreover, FB exposure resulted in the disproportional development of the rat offspring in a dose-dependent manner, which was probably caused by the bodily hormonal dysregulation. Prenatal fumonisin exposure can be a pathological precursor for serious diseases, such as obesity and diabetes, later in life.
Hemocompatibility is one of the major criteria for the successful cardiovascular applicability of novel biomaterials. In this context, monolayers of certain biomolecules can be used to improve surface biocompatibility. To this end, biocoatings incorporating a phospholipid (1,2-dioleoyl-sn-glycero-3-phosphocholine, DOPC), an immunosuppressant (cyclosporine A, CsA), and an antioxidant material (lauryl gallate, LG) were fabricated by depositing Langmuir films onto gold or mica substrates using the Langmuir-Blodgett (LB) technique. These LB monolayers were thoroughly characterized by means of quartz crystal microbalance (QCM), atomic force microscopy (AFM), cyclic voltammetry (CV), and contact angle (CA) measurements. The obtained results indicate that the properties of these LB films are modulated by the monolayer composition. The presence of LG in the three-component systems (DOPC-CsA-LG) increases the molecular packing and the surface coverage of the substrate, which affects the wettability of the biocoating. From the different compositions studied here, we conclude that DOPC-CsA-LG monolayers with a DOPC/CsA ratio of 1:1 and LG molar fractions of 0.50 and 0.75 exhibit improved surface biocompatible characteristics. These results open up new perspectives on our knowledge and better understanding of phenomena at the biomaterial/host interface.
Ageing is accompanied by dramatic changes in chromatin structure organization and ge-nome function. Two essential components of chromatin, the linker histone Hho1p and actin-related protein 4 (Arp4p), have been shown to physically interact in Saccharomyces cerevisiae cells, thus maintaining chromatin dynamics and function, as well as genome stability and cellular morphology. Disrupting this interaction has been proven to influence the stability of the yeast genome and the way cells respond to stress during chronological ageing. It has also been proven that the abrogated interaction between these two chromatin proteins elicited premature ageing phenotypes. Alterations in chromatin compaction have also been associated with replicative ageing, though the main players are not well recognized. Based on this knowledge, here, we examine how the interaction between Hho1p and Arp4p impacts the ageing of mitotically active yeast cells. For this purpose, two sets of strains were used-haploids (WT(n), arp4, hho1Δ and arp4 hho1Δ) and their heterozygous diploid counterparts (WT(2n), ARP4/arp4, HHO1/hho1Δ and ARP4 HHO1/arp4 hho1Δ)-for the performance of extensive morphological and physiological analyses during replicative ageing. These analyses included a comparative examination of the yeast cells' chromatin structure, proliferative and reproductive potential, and resilience to stress, as well as polysome profiles and chemical composition. The results demonstrated that the haploid chromatin mutants arp4 and arp4 hho1Δ demonstrated a significant reduction in replicative and total lifespan. These findings lead to the conclusion that the importance of a healthy interaction between Arp4p and Hho1p in replicative ageing is significant. This is proof of the concomitant importance of Hho1p and Arp4p in chronological and replicative ageing.
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