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The metal accumulation and antioxidant contents in flowers of wild specimens of European elder (Sambucus nigra L.), a famous medicinal plant and valuable component in the urban landscape, were determined. The total reflection X-ray fluorescence revealed the presence of K, Rb, Ca, Sr, Cr, Mn, Fe, Cu, and Zn associated with flowers. A typical, large, non-industrial city with considerable traffic and atmospheric pollution resulting from smog was chosen as a place of sampling. Obtained results were correlated with selected parameters of soil and the intensity of surrounding traffic. The flowers were relatively rich in elements K, Ca, Cu, Rb, and antioxidants, while it did not accumulate heavy metals potentially bioavailable in the soil. The correlation between street traffic and the content of Fe, Cr, and Zn in elderflowers was revealed; the metal quantities were below levels harmful to humans. Flowers from the city center exhibited higher antioxidant and radical scavenging capacities comparing to plants from the areas of little traffic. The antioxidant parameters were negatively correlated with the silty fraction content and positively with the potentially bioavailable levels of Ti and Mn in soils and increased with the amount of Rb in the flowers. It was proven for the first time that the urban specimens of wild S. nigra can perform as a local source of beneficial flowers providing cost-effective support in disease prevention and treatment.

Orthodontic appliances discolour over treatment time, and a yellowish plaque builds up on the contact area of the brackets, adhesive and teeth. Brilliant Blue-based plaque-staining agents (BBPSAs), which increase tooth brushing efficiency, have the potential to support the maintenance of proper oral hygiene during orthodontic treatment. However, they exhibit strong colouring properties, and their impact on the aesthetics of braces remains unclear. Therefore, the aim of this study was to investigate the influence of commercially available BBPSAs on the colour of aesthetic orthodontic materials. A light-cured, colour-changing orthodontic adhesive and new-generation, monocrystalline, sapphire brackets were chosen for the experiments. The effect of the staining agent on the tested materials was investigated in terms of the reaction temperature and time, as well as the presence of black tea-induced impurities on the materials. The CIELAB (Commission Internationale de L’éclairage L* a* b*) colour system parameters were measured, and the colour differences (ΔE*ab and ΔE00—the Commission Internationale de L’éclairage 2000 colour-difference) were determined for the materials under several experimental conditions. The braces’ green-red colour expression was positively affected by the BBPSA. Under in vitro conditions, the regular use of the BBPSA for 90 days visibly improved the unfavourable colour change caused by the black tea.

Carbon-based (nano)materials doped with transition metals, nitrogen and other heteroatoms are considered active heterogeneous catalysts in a wide range of chemical processes. Recently they have been scrutinized as artificial enzymes since they can catalyze proton-coupled electron transfer reactions vital for living organisms. Herein, interactions between Gram-positive and Gram-negative bacteria and either metal-free N and/or S doped or metal containing Fe&minus, N&minus, S co-doped porous carbons are studied. The Fe- and N-co-doped porous carbons (Fe&minus, C) exhibit enhanced affinity toward bacteria as they show the highest adsorption capacity. Fe&minus, C materials also show the strongest influence on the bacteria viability with visible toxic effect. Both types of bacteria studied reacted to the presence of Fe-doped carbons in a similar manner, showing a decrease in dehydrogenases activity in comparison to controls. The N-coordinated iron-doped carbons (Fe&minus, C) may exhibit oxidase/peroxidase-like activity and activate O2 dissolved in the solution and/or oxygen-containing species released by the bacteria (e.g., H2O2) to yield highly bactericidal reactive oxygen species. As Fe/N/ and/or S-doped carbon materials efficiently adsorb bacteria exhibiting simultaneously antibacterial properties, they can be applied, inter alia, as microbiological filters with enhanced biofouling resistance.

The paper presents the results of experimental studies on the synthesis and thermodynamic stability of selected Pb-apatites in terms of criteria determining termination of the experiments. Based on the case study, we indicate difficulties in analysing the obtained experimental data. Time-resolved sampling of precipitate formed during a dropwise synthesis of pyromorphite was performed and the results were compared to the literature data. It has been concluded that the Ostwald ripening time for synthesized solids depends primarily on the chemical composition of the intended Pb-apatite phase. We presented that heterogeneity of precipitate affects its dissolution in terms of repeatability of the results and equilibrating time. A unique 9-year-long experiment on vanadinite stability at a pH range from 2.0–6.0 revealed that among all tested dissolution conditions only the reactions at the pH = 3.5 can perform as the basis for some thermodynamic calculations. It has been concluded that the rate of phase transitions in the Pb-apatites group can be misleading in terms of determining the equilibrium of the system, and the experimental setup designed particularly to provide reliable controls in this aspect should be involved. Means in this respect have been proposed.

Due to the great range of the application fields for apatites, there is a strong need to complete the data set determining the properties of these minerals. In this study, Raman and Infrared spectra of the phases from pyromorphite Pb5(PO4)3Cl - vanadinite Pb5(VO4)3Cl series were investigated. Totally, 9 samples (2 end-members and 7 solid solutions of the series) were synthesized at 25°C and pH=3.5, and analyzed. In the Raman and Infrared spectra of the studied Pb-apatites, the bands typical for the vibrations in the PO4 and the VO4 tetrahedra appeared. The bands attributed to the stretching vibrations (ν1, ν3) occurred in the 1050-910cm-1 and 830-720cm-1 regions, whereas the bending vibrations (ν2, ν4) were visible at the 580-540cm-1, 430-380cm-1 and 370-290cm-1 range. The position of the bands depended on the P/(P+V) ratio in the analyzed solid, since there are differences in the ionic radii and the atomic mass of P5+ and V5+, which affect the bong lengths, bond forces and the banding energies of the substituting tetrahedra. The analysis allowed observing gradual shifts of the bands caused by the replacement of phosphorous with vanadium in the studied phases. The positions and the intensities of selected bands are proposed to serve as a semi-quantitative estimation of the chemical composition of the phases from the pyromorphite - vanadinite series.

The effects of temperature and PO4 substitutions on the solubility of a series of vanadinite (Van) Pb5(VO4)3Cl–pyromorphite (Py) Pb5(PO4)3Cl solid solutions were experimentally investigated to determine differences in dissolution mechanisms and to estimate the Ksp and thermodynamic state functions ΔH°f, ΔG°f, S°, and ΔC°p. Dissolution of Van and the selected phases from the Van–Py series at pH 2.0 was congruent at 5 °C, but it became noncongruent with precipitation of a secondary phase - chervetite Pb2V2O7 in the temperature range of 25–65 °C. The isomorphic substitution of VO4 with PO4 reduced the level of Pb released during dissolution into the equilibrium solution from approximately 207.2 mg Pb L−1 for Van to 131 mg Pb L−1 for Py (at 5 °C). This substitution, however, simultaneously caused a very strong increase in the thermodynamic solubility constant Ksp, which showed a large difference (over 14 orders of magnitude) for the end members of the series. The experimentally determined Ksp at 5 °C varied from 10−96.89±0.53 for Van to 10−80.91±0.70 for Py. The variation in Ksp was linear with substitution of VO4 with PO4 and curvilinear with change in temperature. The more the amount of vanadium in the structure, the stronger was the temperature effect. Because of the noncongruent dissolution followed by far from equilibrium state for V-reach samples at higher temperatures, the experimental determination of thermodynamic state functions was possible only for pyromorphite and some P-reach members of Py–Van solid solution series. For Py, ΔH°f = −4098 ± 5 (kJ mol−1), ΔG°f = −3763 ± 4 (kJ mol−1), S° = 667 ± 313.4 (kJ mol−1 K−1), and ΔC°p = −930.9 ± 345.2 (kJ mol−1 K−1). For Van, ΔH°f = −3796 ± 10 (kJ mol−1), ΔG°f = −3486 ± 4 (kJ mol−1), S° = 719 ± 694 (kJ mol−1 K−1), and ΔC°p = −1037 ± 605 (kJ mol−1 K−1) were estimated.

Introduction: Primary prevention of hypertension underlines the relevance of body composition abnormalities, particularly of so-called lean body mass. Increased fructose intake can lead to elevated blood pressure. Aim: The aim of this study was to assess the metabolic profile and dietary fructose intake in prehypertensive and hypertensive adolescents. Material and methods: Thirty-one patients (18 boys and 13 girls) aged 12–18 years (median: 15 years) with well controlled hypertension and prehypertension were selected for the study. The authors measured body height and weight, body mass index, waist-to-hip ratio, waist-to-height ratio as well as fat content and lean body mass using bioelectrical impedance analysis. The patients’ diet was assessed in terms of fructose intake and food energy value. Results: Forty-two per cent of children (33% of boys and 61% of girls) had abnormally high body mass index (BMI z-score > 2.0 SDS). The waist-to-height ratio was significantly higher in girls than in boys (0.53 and 0.45, respectively, p = 0.04). The results in waist circumference z-score were similar (2.82 vs. 1.13, respectively, p = 0.02). Girls had greater fat mass than boys (31% vs. 17%, respectively, p = 0.001). The energy value of girls’ diet was lower (1,967 vs. 2,683 kcal, p = 0.003), but excessive energy intake was observed in both groups (120% of requirement). Dietary fructose intake covered 11% of energy requirement. Conclusions: The study demonstrated that girls with elevated blood pressure have a greater amount fat tissue than boys and its distribution is more unfavourable. The diet of children with elevated blood pressure values is characterised by excessive energy delivery, and dietary fructose intake exceeds daily recommended intake of simple sugars.

Although vanadinite (Pb5(VO4)3Cl) occurs in abundance in various terrestrial geochemical systems of natural and anthropogenic origin and is seriously considered as a potential nuclear waste sequestering agent, its actual application is severely limited by a lack of understanding of its basic thermodynamic parameters. In this regard, the greatest challenge is posed by its incongruent dissolution, which is a pivotal hurdle for effective geochemical modeling. Our paper presents an universal approach for geochemical computing of systems undergoing incongruent dissolution which, along with unique, long-term experiments on vanadinites&rsquo, stability, allowed us to determine the mineral solubility constant. The dissolution experiments were carried out at pH = 3.5 for 12 years. Vanadinite has dissolved incongruently, continuously re-precipitating into chervetite (Pb2V2O7) with the two minerals remaining in mutual equilibrium until termination of the experiments. The empirically derived solubility constant KspV,298 = 10&ndash, 91.89 &plusmn, 0.05 of vanadinite was determined for the first time. The proposed modeling method is versatile and can be adopted to other mineral systems undergoing incongruent dissolution.

The solubility of synthetic pyromorphite Pb5(PO4)3Cl was determined in a series of dissolution experiments conducted at 5–65 °C and at pH = 2.0. The equilibrium was established within 4 months. The dissolution of pyromorphite was congruent at all the temperatures, and the measured solubility product log Ksp,298 for the dissolution reaction: Pb 5 ( PO 4 ) 3 Cl ⇔ 5 Pb 2 + + 3 PO 4 3 - + Cl - was determined to be −79.6 ± 0.15. The equilibrium ion activity product of pyromorphite increased with temperature, indicating a positive enthalpy of the dissolution reaction in the temperature range from 5 to 65 °C. The temperature dependence of the log Ksp was nonlinear: log Ksp = A − B/T + D log(T), where A = 478.77 ± 136.62, B = 29,378 ± 6215, and D = −185.81 ± 46.77. This allowed for calculation of ΔG°r = 454.0 ± 1.7 kJ·mol−1, ΔH°r = 101.8 ± 6.0 J·mol−1·K−1, ΔC°p,r = −1545 ± 388.9 J·mol−1·K−1, and ΔS°r = −1181 ± 382 J·mol−1·K−1 of the dissolution reaction. Using these values and the published standard state quantities for constituent ions, the values of ΔG°f = −3764.3 ± 3.5 kJ·mol−1, ΔH°f = −4108.4 ± 7.9 J·mol−1·K−1, S°f = 622 ± 382 J·mol−1·K−1, and C°pf = 402 ± 398 J·mol−1·K−1 were calculated for synthetic pyromorphite Pb5(PO4)3Cl.

Introduction. Difficulties in the echocardiographic assessment of single ventricle function, particularly with right ventricular morphology, prompt to use different available echocardiographic techniques. Echocardiographic evaluation of the degree of hemodynamic disturbances affecting systemic ventricular function not only allows better investigation of the cardiovascular system but also helps determine prognostic factors to guide further therapeutic decisions. The role of tissue Doppler imaging (TDI) in paediatric patients with univentricular heart has been highlighted but only few studies evaluated the utility of this method in the evaluation of systemic ventricle systolic and diastolic function after the Fontan procedure. The aim of the study was to assess the relationship between conventional echocardiographic and TDI parameters in the evaluation of the performance of a functional single right ventricle in children with hypoplastic left heart syndrome (HLHS) after the Fontan procedure. Material and methods. A total of 34 patients with HLHS after staged surgical treatment culminating in the Fontan procedure underwent evaluation, including medical interview, physical examination, electrocardiography, and transthoracic echocardiography in standard views using M-mode, two-dimensional imaging, continuous and pulsed wave Doppler, colour Doppler, and TDI. The effect of demographic and perioperative factors on selected parameters of the echocardiographic evaluation of systemic ventricular function was analysed. In addition, we evaluated relations between conventional echocardiographic and TDI parameters in the evaluation of single right ventricular function in children after Fontan procedure. Results. Statistical analysis showed no significant correlation between TDI parameters of systolic and diastolic function (E’, E’/A’) and standard echocardiographic indices (E, A, E/A). Likewise, no significant correlation was found between the myocardial performance index (MPI) obtained from TDI and conventional MPI. A significant correlation was found between the E/E’ ratio and MPI. Conclusions. No significant correlation found in children after Fontan procedure between diastolic function parameters and right ventricular MPI measured using TDI and conventional echocardiographic parameters indicates that TDI is a technique complementary to conventional echocardiography in the evaluation of single right ventricle function in children. In addition, TDI does not depend on preload, and thus it can be speculated that this technique may identify ventricular dysfunction (mostly diastolic) at a stage when conventional echocardiographic parameters are still normal. Further studies in a larger number of patients are needed to support these conclusions.

Five lead-arsenate apatites (mimetites)-Pb5(AsO4)3X&mdash, where X denotes fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and hydroxide (OH)&mdash, were synthesized via precipitation from aqueous solutions. The crystal structures were determined through Rietveld refinement of powder synchrotron X-ray data. All the compounds crystallized in the hexagonal class symmetry (space group P63/m). The Rietveld refinement indicated that mimetite-Cl, -Br, -I, and -OH had an anion deficiency at position X. Substitution of halogens in a mimetite structure brought about systematic changes in unit-cell parameters, interatomic distances, and metaprism twist angles &phi, proportional to the substituted halogen&rsquo, s ionic radius. Mimetite-OH did not follow the linear correlations determined within the series. Twist angle &phi, a useful device for monitoring changes in apatite topology, ranged from 20.34&deg, for mimetite-F to 11.42&deg, for mimetite-I. The geometric method has been proposed for determining the diameter of hexagonal channels hosting halogens in apatites. A comparison of the results with halogenated pyromorphites showed similar systematic trends: the substitutions in mimetites have comparable effect on the interatomic distances as in their phosphorous analogues.

Lead-containing (Pb-B-X)-2Hapatites encompass a number of [AF]4[AT]6[(BO4)6]X2compounds used for waste stabilization, environmental catalysis and ion conduction, but the influence of the stereochemically active lone-pair electrons of Pb2+on crystal chemistry and functionality is poorly understood. This article presents a compilation of existing structural data for Pb apatites that demonstrate paired electrons of Pb2+at both theAFandATresults in substantial adjustments to the PbFO6metaprism twist angle, φ. New structure refinements are presented for several natural varieties as a function of temperature by single-crystal X-ray diffraction (XRD) of vanadinite-2H(ideally Pb10(VO4)6Cl2), pyromorphite-2H(Pb10(PO4)6Cl2), mimetite-2H/M(Pb10(As5+O4)6Cl2) and finnemanite-2H(Pb10(As3+O3)6Cl2). A supercell for mimetite is confirmed using synchrotron single-crystal XRD. It is suggested the superstructure is necessary to accommodate displacement of the stereochemically active 6s2lone-pair electrons on the Pb2+that occupy a volume similar to an O2−anion. We propose that depending on the temperature and concentration of minor substitutional ions, the mimetite superstructure is a structural adaptation common to all Pb-containing apatites and by extension apatite electrolytes, where oxide ion interstitials are found at similar positions to the lonepair electrons. It is also shown that plumbous apatite framework flexes substantially through adjustments of the PbFO6metaprism twist-angles (φ) as the temperature changes. Finally, crystalchemical [100] zoning observed at submicron scales will probably impact on the treatment of diffraction data and may account for certain inconsistencies in reported structures.

Remediation of lead (Pb)-contaminated sites with phosphate amendments is one of the best studied and cost-effective methods for in situ immobilization. In this treatment, a very stable mineral, pyromorphite Pb5(PO4)3Cl, is formed. Several studies propose to improve this treatment method with the addition of phosphate-solubilizing bacteria (PSB). The effect of bacteria on solubilization of pyromorphite is unknown. In this study, the effect of the soil microorganisms on the stability of pyromorphite Pb5(PO4)3Cl has been investigated in a set of batch solution experiments. The mineral was reacted with Pseudomonas putida, a common soil microorganism. Dissolution of pyromorphite was enhanced by the presence of P. putida, resulting in an elevated Pb concentration in the solution. This occurred even when the bacteria were provided with an additional source of phosphate in the solution. Pyromorphite has been shown to be a potential source of nutrient phosphorus for common soil bacteria. Thus, the use of PSB in remediation treatments of Pb contaminated sites may have adverse long-term impacts on Pb immobilization. Conscious phosphate management is suggested for long-term sustainability of the in situ Pb immobilization by pyromorphite formation.

Pyromorphite Pb 5 (PO 4 ) 3 Cl and vanadinite Pb 5 (VO 4 ) 3 Cl belong to the apatite supergroup. They are secondary minerals formed in the oxidation zones of lead ore deposits. Both crystallize in hexagonal symmetry with the space group P6 3 /m (Dong et al. 2002). The crystal structure of these two minerals allows to accommodate both metal cations and anionic complexes. It is the reason, why pyromorphite and vanadinite forms solid solution series. Isovalent replacement of P with V is one of the most common anionic substitution. Lead apatites are one of the least soluble along apatites group minerals and characterized by high thermal stability (Dong et al. 2002, Flis et al. 2011). Characteristic properties of apatite structure cause that these minerals are successfully used in many fields, especially for the immobilization of toxic waste and lead-contaminated soil (Ma et al. 1993, Chen et al. 1997, Dong et al. 2002, Kim et al. 2005). So far, pyromorphite and mimetite are the most known and used for the immobilization of lead. Pyromorphite and mimetite are isostructural with vanadinite, therefore it has been predicted that this mineral is also important for the environment. Accordingly, the aim of this study was to characterize of the pyromorphite-vanadinite solid solution series. This research present systematic changes in the structure of these minerals. Pure pyromorphite and vanadinite and minerals with intermediate compositions Pb 5 (TO 4 ) 3 Cl, where T = P + V, of various P/V ratios were synthesized from aqueous solutions at 298 K and pH = 3.5. Synthetic solids were analyzed by X-Ray diffraction (XRD), infrared absorption spectroscopy (FTIR) and Raman spectroscopy. Based on the X-Ray analysis, it was found that synthetic precipitates represent homogeneous phases of pyromorphite and vanadinite, which have intermediate chemical composition. Diffraction peaks of pyromorphite-vanadinite solid solution series were shifted due to replacement of PO 4 by VO 4 . Replacement of PO 4 by VO 4 anions is causing changes in the structure of apatite and hence these shifts. Unit cell parameters of studied solid solutions show a linear variation. In the FTIR and Raman spectra of pyromorphite-vanadinite solid solutions series, the bands which are characteristic for vibrations of P-O bonds of the PO 4 tetrahedra as well as vibrations of V-O bonds of the VO 4 tetrahedra appeared. Analysis of Mid-IR spectra and Raman spectra also allowed to observe correlation between the band positions and the extent of the anionic substitution among the studied series. The structure of pyromorphite and vanadinite is generally similar, although they vary in chemical composition. Causes of variability are probably connected with the properties of individual ions. The project was financed with resources of the National Science Centre, Poland, granted based on decision no. DEC-2013/09/N/ST10/00677.