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It is indefinite for research applications if prolonged freeze-stored serum from Schistosoma-infected patients is useful. We assessed − 20 ̊C freezing as a rapid and inexpensive method. A longitudinal cohort study with staggered follow-up periods evaluated the impact of cryopreservation on serum residues from 24 Schistosoma-infected Egyptian patients. Fresh serums were collected in March 2022 and assessed by the indirect haemagglutination test for Schistosoma immunoglobulin titrations and calorimetric assays for ALT, AST, total serum protein, Na+, K+, Ca++, and Mg++ (baseline values). Sera were then frozen and categorized into 4 groups (6 patients each) according to freezing duration; 3 months (group-1), 6 months (group-2), 9 months (group-3), and 12 months (group-4). Re-evaluation was performed on the Schistosoma immunoglobulin recovery rates and all other serum chemical factors. Baseline assessment showed increased mean values of Schistosoma immunoglobulins, ALT, AST, and proteins; yet, Ca++, Na+, and K+ were reduced. Mg++ showed normal values. Compared with the baselines, − 20 °C freezing showed significant deviations and increased percentage change in Schistosoma immunoglobulin titers, ALT, AST, K+, and Na+ at different time intervals of archiving (p-value ≤ 0.05). Evaluating serum factors interactions post-thawing revealed that AST correlated positively with ALT and Mg++ sera levels whereas Ca++ negatively correlated with Na+ and Schistosoma antibody titer. Analyzing baselines revealed that the parasite alters levels of immunoglobulin, ALT, AST, proteins, Ca++, Na+, and K+. − 20 °C cryopreservation did not guarantee the stability of all tK+hese serum parameters. In addition, some serum factors appeared to interact together. Assessing the efficacy of − 20 °C freezing on the next-generation sequencing is recommended. [ABSTRACT FROM AUTHOR]

Despite significant advances in prenatal medicine, spontaneous miscarriage remains one of the most common and serious pregnancy complications, affecting an increasing number of women. Since many aspects of the pathogenesis of spontaneous miscarriage remain unexplained, the aim of this study has been to assess the involvement of the NLRP3 inflammasome as a potential causative factor. The concentrations of NLRP3, IL-1β, IL-18, and cytochrome C in the serum of patients after miscarriage were measured by means of the immunoenzymatic method. In the placental tissue, the expression of NLRP3, IL-1β, IL-18, and Caspase-1 as well as that of the classical apoptosis biomarkers Fas, FasL, Bcl-2, and Ca was evaluated by means of immunohistochemistry techniques. Additionally, in whole blood, the concentrations of elements crucial for pregnancy progression, such as Ca, K, Mg, and Na, were examined by means of the ICP-OES method. Significantly higher concentrations of NLRP3 and IL-18 were demonstrated in the serum of patients with miscarriage as compared to the control group. In the placental tissue samples, a higher expression of IL-1β, IL-18, and Caspase-1 proteins was noted in women who had experienced miscarriage as compared to the control group. At the same time, a significantly lower expression of FasL and Bcl-2 proteins as well as Ca deposits was observed in women after miscarriage as compared to those with a normal pregnancy outcome. Significantly lower concentrations of Ca and K were recorded in the blood of patients with spontaneous miscarriage as compared to pregnant women. The analysis of the results x indicated a greater involvement of the inflammasome in women with spontaneous miscarriage associated with oxidative–antioxidative imbalance than in the case of miscarriage related to NET formation. Our research has provided evidence for the involvement of the inflammasome in the process of spontaneous miscarriage and identifies a new direction for diagnostics that includes NLRP3 as a preventive element in prenatal care, particularly in light of the steadily declining number of pregnancies and the increasing number of reproductive failures. [ABSTRACT FROM AUTHOR]

Solanum microdontum (mcd) is a tuber-bearing relative of commercial potato. Although wild, it has many attractive traits for breeding. Previous research has shown it has exceptional ability to sequester calcium in its tubers, a trait associated with tuber disease resistance and tuber quality. We used a set of mcd from 50 populations in the US Potato Genebank (USPG) shown to encompass most of the genetic diversity in the species, two individuals from each population. Tubers were produced in pots in the USPG greenhouse in two years, and freeze dried samples tested for calcium content. Some exceptionally high Ca accumulators were identified (especially clone mcd40B1 from PI 473166). Because other minerals were measured in the same tests, the highest accumulators for K, Mg, Zn in mcd were also identified. All the stocks tested are available in vitro from USPG for additional research and breeding. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to assess the effects of various organic materials on Dactylis glomerata yield, on the content of selected macroelements (K, Ca and Mg) and on K:Ca, K:Mg and K:(Ca + Mg) ratios. As a valuable forage plant, Dactylis glomerata (cocksfoot grass) is a common grass in Poland both in grassland and in arable fields. Its rapid spring growth and its resistance to drought, low temperatures, but also to frequent mowing and pests, makes it a common species in meadows, pastures and grassland, both permanent and alternating. In order to achieve the research goal, a three-year pot experiment was established in a greenhouse. The experiment was conducted in a completely random design, in four replications. In the autumn before the experiment, soil was mixed with organic materials (chicken manure, mushroom substrate and rye straw) and put into pots. To selected units, an additional amount of mineral N was applied in the first year and NPK fertilizers in consecutive years. Mineral fertilizers were applied at the beginning of the growing period. Compared to control, the application of mineral and organic fertilizers resulted in a significant increase in Dactylis glomerata yield. The highest biomass yield (average over the growing periods) was recorded on the unit treated with manure, straw and mineral fertilizers (27.64 g·pot-1) and on the one with mushroom substrate applied together with rye straw and mineral fertilizers (26.47 g·pot-1). The K:(Ca+Mg) ratio in the forage was normal and averaged 0.933, but mineral fertilizers, compared to other treatments, narrowed it. [ABSTRACT FROM AUTHOR]

Information on different compounds of elements, such as Na, K, Ca, Mg, Al, Fe, and Mn, contributes to our understanding of the genesis of poorly studied soils of northern coasts. The analysis has been carried out of the composition of various forms of compounds. To determine total element contents, a mixture of concentrated HF, HClO4, and HCl was used; acid-soluble forms were extracted with a mixture of concentrated HNO3 and H2O2; and acetate ammonium buffer solution was used to determine mobile forms. It is shown that the amount elements added to the tidal marsh zone is largely determined by the volume and composition of solids entering with seawater and with runoff from coastal catchments. For mineral soil horizons, a close correlation is found between the contents of clay fraction and exchangeable forms of K, Mg, and Al (R2 = 0.4–0.5), as well as between the contents of clay and highly mobile forms of these elements and Fe (R2 = 0.6–0.8). The distribution of elements along the profile of zonal soils on the highest positions of the relief is significantly influenced by the permafrost conditions and the aerial transfer of salts with seawater drops. [ABSTRACT FROM AUTHOR]

Biochar affects base cation retention and leaching when it is used to enhance the base cation status of acidic soil. However, the details of its contribution are not yet clear. In this study, six loadings of corn straw biochar (0%, 2%, 4%, 6%, 8% and 10%, w/w) were applied to an acidic Ferralsol and incubated for 1 year. The results showed that the content of water‐soluble and exchangeable base cations of K, Na, Ca and Mg increased with increasing levels of biochar in amended soil. The percentage of water‐soluble Na, Ca and Mg of amended soil significantly decreased, while the percentage of exchangeable K, Ca and Mg increased significantly after the addition of biochar. For K and Na, biochar affected their leaching concentrations both as a source and by increasing the pH. For Ca, biochar reduced Ca leaching when the biochar loading was ≥4%, and the contribution increased from 30.8% to 100% at 4%–10% loading. For Mg, biochar reduced Mg leaching at biochar loadings 2%–10%, the reduction increasing from 22.0% to 70.5%. The results show that corn straw biochar can increase the content of the soil nutrient base cations K, Ca and Mg by increasing their exchangeable forms and enhance soil retention by decreasing their leaching. Thus, corn straw biochar can be used to effectively improve acidic soil base cation fertility. [ABSTRACT FROM AUTHOR]

Apple is grown in various parts of the world and consumed year-long in four seasons. The nutrient contents of fruit constitute the bases for several disorders experienced in storages. Although leaf analyses are used worldwide to assess the nutritional status of fruit trees, they may not yield accurate outcomes for assessment of fruit nutrient contents. Even if leaf nutrient contents are enough or quite high, various physiological disorders on fruits may be resulted from nutrient deficiencies. Fruit analyses should be performed to determine fruit nutrient contents and accordingly to improve flesh quality and to take relevant measures in early periods. In this study, fruit samples were collected for 2 years from 260 apple orchards in Isparta province of Turkey in 6 different periods covering the timeframe from June drops to harvest and fruit nutrient contents were determined from these samples. Firstly, seasonal variations of nutrients were examined. It was observed that fruit nutrient contents decreased periodically and this decreasing was quite faster through the early periods of the vegetation. Secondly, correlations between nutrient contents of the fruits sampled at the last period and the nutrient contents of the fruits sampled at earlier periods were also investigated in this study. Significant correlations revealed that fruit nutrient contents could be traced between the relevant periods and reference values could be established for these periods. Positive outcomes were observed for investigated nutrients except for N, Fe and Zn. [ABSTRACT FROM AUTHOR]

The composition of biologically active substances in the aqueous total fraction of the 95% EtOH extract of the aerial part of Alfredia cernua (L.) Cass. possessing antiamnesic properties was studied using chromatographic and mass-spectrometric methods. The total amount of N-containing compounds in the fraction was found to be 10.63 ± 1.65%. Fifteen amino acids (1.99 ± 0.11%), seven of which (0.76 ± 0.012%) were essential and included lysine, threonine, valine, isoleucine, leucine, phenylalanine, and histidine, were identified using an amino-acid analyzer. The total fraction was dominated by glutamic and aspartic acids, valine, proline, alanine, and histidine. The composition included a total of 43 elements (1.35 ± 0.1%), of which 19 were essential or conditionally essential. The predominant elements were K, Mg, Zn, Rb, P, Ca, and Mn. Carbohydrates dominated (32 ± 3.1%) the fraction. [ABSTRACT FROM AUTHOR]

The study was conducted on the Słup reservoir and the Nysa Szalona river (Poland). The material was benthic water and sediments. The aim of the study was to evaluate accumulation of Ca, Mg, Na and K in the sediments. The assessment of studied elements accumulation was based on calculations of the cumulation factor in the sediment. On this basis, an attempt was made to assess the possible impact of the compounds deposited in the sediment on the organisms living in the reservoir and on the change in the composition of water which constitutes the basis for drinking water. It was found that the studied sediments are rich in Ca, Mg and K compounds but relatively poor in sodium compounds. The level of the studied elements in the sediment and water in the annual cycle does not show strong changes and in the relatively stable conditions existing in the reservoir it does not pose a threat to organisms living there. Moreover, it does not adversely affect the composition of water which is obtained for water supply purposes. [ABSTRACT FROM AUTHOR]

Sample preparation is a crucial stage in obtaining correct results for micro- and macro-elements in soil and plants. The current study is a part of systematic research on the methods for soil and plant sample preparation for analysis of the most important macro-elements. The purpose is to determine the limits of the application of the most widely spread standardized and non-standardized methods for sample preparation and to shed more light on the possibilities of using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS) and X-ray Diffraction (XRD) in soil and plant analysis. The most common methods for extracting macro- elements in soil and plants (dry ashing, acid digestion, and microwave digestion in different variants) were compared using three certified soil samples and the Polish reference material CTR-VTL-2 (Virginia tobacco leaves). Three macro-elements (K, Ca and Mg) in the digest were analyzed using flame AAS and the insoluble fraction after digestion were analysed using XRD and SEM-EDS. It is concluded, that the degree of extraction of the elements from soil and plant materials is highly dependent on the mineralisation method. The X-ray investigation showed the formation of KClO4 when HClO4 was used as a part of the acids mixture. The use of HF at Ca and Mg determination led to the formation of CaF2 and MgF2. The result was verified by SEM-EDS. [ABSTRACT FROM AUTHOR]

Biological pumping of mineral elements (root uptake from the soil and concentration at the surface via litterfall) may be an important mechanism influencing their loss from terrestrial ecosystems by accelerating transport in runoff, though few estimates exist to assess this. In the Susquehanna Shale Hills Critical Zone Observatory (a temperate forested watershed in central Pennsylvania), we compared two independent methods (litterfall‐based and transpiration flow‐based) for estimating the total uptake of elements (Ca, K, Mg, Mn, Si, Sr, and Al) by canopy trees. Elemental concentrations were measured monthly in leaf tissue and xylem sap of dominant species Quercus rubra (chestnut oak), Q. prinus (red oak), and Acer saccharum (sugar maple) for two growing seasons. Species‐specific litterfall and transpiration (estimated by eddy covariance) were used to scale concentrations to annual fluxes. For most elements, both methods generated comparable gross fluxes in the range of 53–85 (Ca), 9–19 (Mg), 14–28 (Mn), 0.2–0.6 (Al), and 0.1–0.3 (Sr) kg·ha−1·year−1. For K, litterfall‐based methods generated substantially lower estimates than transpiration, though neither accounted comprehensively for leaching from live foliage, resorption, or potential recycling within the growing season. For most elements, uptake rates were similar in magnitude to stream losses, implying a low degree of recycling. For K and Mn however, biological uptake exceeded losses by 1–2 orders of magnitude, suggesting a biological role in ecosystem retention. We conclude that litter‐ and transpiration‐based methods can be combined to broadly estimate the magnitude of biological pumping, with additional measures of wood‐/root‐based turnover necessary for more accurate budgets. Plain Language Summary: Elements such as silicon and calcium that are weathered from rocks can be moved from deep in the soil to the surface through uptake by plant roots and subsequent litterfall. At the surface, these elements are more vulnerable to being lost from an ecosystem by being eroded or washed into waterways, where they can eventually influence downstream processes such as ocean carbon uptake. It is difficult to estimate how important transport by trees is for element loss (or for recycling within the ecosystem) without good measurement methods. Here we compared two methods for estimating tree uptake of seven elements by measuring their concentrations in either leaf litter or plant sap. We measured three dominant tree species (oaks and maples) in a temperate forest catchment in central Pennsylvania and used total litterfall and sap flow to scale these concentrations into annual uptake rates. For most elements, both methods generated similar estimates that showed that the amount taken up by trees was similar to the amount lost in streams every year. However, for potassium and manganese, tree uptake was much greater than stream loss, suggesting that incorporation into tree litter helps to retain these elements within the ecosystem. Key Points: Uptake of mineral elements by trees may be a major pathway of redistribution, affecting hydrologic loss and soil formationWe compared a novel transpiration‐based method with a litterfall‐based approach to estimate watershed‐scale uptake fluxesFor most elements (excluding K), methods generated similar fluxes, and biological uptake was of comparable magnitude to hydrologic losses [ABSTRACT FROM AUTHOR]

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K and Mg codoped BST powders were prepared by a sol-gel method, and the effect of doped concentration on the dielectric performances was studied. For comparison, pure, Mg doped and K doped BST powders were studied. XRD shows all powders reveal complete diffraction peaks and ABO3 cubic perovskite polycrystalline structures. Compared to the pure BST powder, Mg doped BST powder shows a little weaker crystallization, 5%∼15% K doped BST powders exhibit stronger crystallization, and the crystallization is getting stronger with increasing K doped concentrations from 2% to 15%. BST powder shows lattice parameter of 3.963 Å, Mg doping corresponds to 3.963 Å, 2%∼20% K doping correspond to 3.963 Å∼3.967 Å, and Mg and K codoping make lattice parameters increase from 3.967 Å to 3.974 Å. Mg2+ ion and K+ ion show acceptor doped mechanisms, Mg doping makes grains refine, and K doping makes grains grow. Pure BST powder and Mg doped BST powder show uniform grains with unclear grain boundaries, K doped BST powders can obtain uniform and dispersive grains with clear grain boundaries, but Mg and K codoping makes the uniformity and dispersity of the powders getting worse. Compared to pure BST powder, Mg doped BST powder shows smaller but more stable dielectric constant and dielectric loss, K doped powders tend to reveal larger and less stable dielectric constants and dielectric losses. Mg and K codoped BST powders show less than 35 dielectric constants, and lower than 0.02 dielectric losses. Dielectric properties are strongly dependent on the crystallization, doped mechanism and morphology. Mg doped and 2% Mg 2% K and 2% Mg 5% K codoped BST powders show low and stable dielectric constants and dielectric losses, thus can meet the requirements for tunable microwave applications and other applications. [ABSTRACT FROM AUTHOR]

This work describes a quick and easy method for the quantification of a series of macroelements (Na, Mg, P, Cl, K, and Ca) and trace elements (Fe and Zn) by energy-dispersive X-ray fluorescence (ED-XRF). The method was developed and validated using commercial dehydrated bouillon and sauce base products. All samples were systematically powdered and analyzed by reference methods (i.e., potentiometry for chloride and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) for other elements) and by ED-XRF. A calibration set of 15 samples was selected to cover uniformly the concentration range of each element, and their reference method values were used to calibrate the ED-XRF device. A second validation set, composed of 26 additional samples, was then analyzed as though they were unknown samples. During this validation step, the elemental concentrations obtained by ED-XRF were systematically evaluated against those obtained from the reference methods. For the eight investigated elements, the ED-XRF method was found to be comparable to the reference one; furthermore, the bias between both methods was found to be not significantly different from 0. For the macroelements, the relative uncertainties RSD(u) were found to be lower than 20%. These results have demonstrated that ED-XRF is a quick and reliable method for the quantification of the listed elements in dehydrated bouillon and sauce base products. The capability to accurately measure trace elements (below 20 mg/kg), while also being able to measure a concentration of several tens of gram per 100 g of NaCl, makes ED-XRF a perfect tool to check the correct addition of premixes and also to ensure the correct claim of macroelements, respectively. [ABSTRACT FROM AUTHOR]

The field experiment was carried out at The Experimental Station of Plant Varieties Protection in Szczecin Dąbie. The experiment aimed at evaluating the influence of slurry with and without increasing doses of PRP FIX preparation on some soil fertility indicators after test plants harvest. The contents of determined macronutrients in the soil were higher in objects where slurry was applied with addition of 8 kg or 12 kg of PRP FIX per 1 m3 as compared to those with exclusively mineral fertilization or slurry. The soil after test plants harvest contained more N, Corg., P, K, Mg, Ca, S, and available forms of P, K, Mg and SO3, in relation to levels before experiment establishment. In general, more soil fertility indicators were recorded in objects treated with the slurry along with PRP FIX preparation and additional PK nutrition (series II) as compared to series I. Differences in macronutrients in the soil due to the fertilization system applied were diverse, however, they not always were significant. [ABSTRACT FROM AUTHOR]

This study was conducted during 2015 and 2016 growing seasons at a private orchard at EI-Nubaria region, EI-Behira Governorate, Egypt. The objective of this study was to investigate the response of "Anna" apple trees budded on Malus rootstock to three amounts of irrigation water using drip irrigation system; I1 : like irrigation water amount the local farmers in the studied regions ( control, 15.584 m3/treelyear ) , 12 :75% from the control ( 11.657 m3 /tree/year) and I3 :50% from the control (7.792 m3/tree/year), foliar spray included four treatments :W (tap water without K and Mg ), K, Mg and K+ Mg, 4 times applications, starting after fruit set, and the others 15 days intervals (K added as potassium SUlphate at rate 2gIL , Mg added as magnesium SUlphate at rate 2g1L) and their interactions on vegetative growth, water relations, leaf chlorophyll and mineral contents, yield and fruit quality of "Anna" apple trees. The experimental trees had the same volume and shape and were grown in a sandy loam soil, spaced at 5x5 meters apart and received the normal culture practices commonly adopted for this region. The main results can be summarized as follows: Foliar application of investigated nutrients increased leaf area, specific leaf weight, leaf chlorophyll, leaf- N, P, K and Mg contents, fruit set, fruit weight, yield, fruit firmness, total soluble solids% and anthocyanin compared to the unsprayed trees in the two growing seasons. The application of K+Mg gave the highest values, the application of K alone was superior to the individual application of Mg. On the contrary, foliar spray with these nutrients didn't show a significant differences on fruit juice acidity in the two seasons. Also, it was observed that, K and (K+Mg) treatments significantly increased total water content and decreased water deficit percentage in leaves compared to Mg or control (W). Mg treatment decreased total water content compared to the control. As for the effect of irrigation rates, the results revealed that (11) treatment was superior for leaf area, total water content, leaf chlorophyll reading and leaf-N, P, K and Mg contents. Also, fruit set as well as yield and fruit weight as compared to the other treatments in the two seasons. 1 2 treatment recorded the highest values of specific leaf weight in the two seasons and total soluble solids in the second one. On the other hand, (13) treatment gave the highest significant value of water deficit, fruit firmness and anthocyanin in the two seasons, and total soluble solids in the first season for "Anna" apple. The interaction effects between the foliar application of investigated nutrient and different irrigation treatments revealed that, (K+Mg) x11 gave the highest significant mean values of leaf area, total water content and leaf-P content in the second season, fruit weight in the first one, also, leaf-N and K contents as well as yield per tree and total yield (ton/fed) in both seasons, while the interaction between (K+Mg) and 13 gave the highest significant values of total soluble solids%, fruit juice acidity and anthocyanin in the first season, and fruit firmness in the second one. It could be recommended from this study that, Potassium and magnesium fertilizers have improved vegetative growth, yield and fruit quality of "Anna" apple and increasing water use efficiency (WUE) under using a lot of water supply with no offering to water deficit condition. Sprayed "Anna" apple trees with Mg and K gave the best results as compared to the individual applications. [ABSTRACT FROM AUTHOR]

Geobotanical studies comprised soil and permanent grasslands in the valley of the Por River. The paper describes an assessment of the content of organic matter, reaction (pH) and availability of P, K and Mg in meadow soils overgrown with plant communities classified within the following syntaxonomic units: associations Phragmition and Magnocaricion, orders Molinietalia and Arrhenatheretalia, classes Scheuchzerio-Caricetea nigrae and the order Trifoliofragiferae-Agrostietalia stoloniferae. The results of chemical analyses were confronted with the limit ordinals after IUNG in Puławy (1990) and submitted to statistical analysis using the system of SAS 9.2 from Enterprise Guide 4.2. The analyzed habitats of permanent grasslands had neutral reaction and were dominated by organic soils. Mineral soils occurred in a small area. Generally, a very high or high availability of assimilable P, a low or very low availability of K and a differentiated content of Mg were found in organic soils. In mineral soils, on the other hand, a very high content of P and Mg and a very low content of K were observed. Comparative analyses of selected properties of the habitats showed very significant diversity. Variability coefficients were generally characterized by high values, which points to considerable differentiation of the analyzed properties of the soils within the distinguished syntaxonomic units. Based on our analysis of the Pearson's correlation coefficients, a number of relations, both positive and negative ones, can be noticed between the properties studied. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine and compare the content of sodium, potassium, calcium, magnesium, zinc, copper, lead, and cadmium in sheep and goat milk of different breeds from 9 farms in the Czech Republic (herds of 18-330 goat's heads and 30-380 sheep heads). Pool samples of milk were collected once a month (April - September) during lactation in the years 2011-2013. The content of minerals was determined using atomic absorption spectroscopy. Most of the analyses of the contents of Cd and Pb were below the limit of detection. Other determined values of these two contaminants were lower than maximal tolerable amount according to previously valid regulation No. 298/1997 Sb of the Ministry of Health of the Czech Republic given for cow's milk. The contents of each element in the whole of the reference period were in a relatively wide range. Determined levels of Ca, Mg, K, Na, Zn and Cu in goat milk related to the weight of lyophilized milk powder varied from 1.40-8.08 g kg-1, 0.16-1.42 g kg-1, 8.16-31.10 g kg-1, 0.72-5.43 g kg-1, 7.59-44.10 mg kg-1, and 0.21-1.46 mg kg-1 respectively. Determined levels of Ca, Mg, K, Na, Zn and Cu in sheep milk varied from 1.69-9.13 g kg-1, 0.21-1.36 g kg-1, 3.53-11.90 g kg-1, 0.65-5.05 g kg-1, 13.70-34.30 mg kg-1, and 0.15-2.10 mg kg-1 respectively. Statistically higher (P < 0.05) content of potassium was determined in goat milk in comparison with sheep milk. The contents of all followed minerals in milk samples from each farm collected during the lactation period were very variable, but it is not possible to find any direct relationship between the content of studied elements and the date of sampling. It was found that the year has statistically significant influence especially on the content of Ca and Mg in milk of small ruminants. [ABSTRACT FROM AUTHOR]

The aim of the study was to monitor milk yield and the hygienic and nutritional quality of milk of Saanen goats in the Moravian-Silesian region in Czech Republic. Milk samples were collected once a month during the lactation period. The average milk yield in the standardized lactation was 1,100 liters. The somatic cell count in pool samples ranged from 470 x 10³ to 696 x 10³. The total microorganism count ranged from 3.6 x 10³ to 1.4 x 105. The pathogen Staphylococcus aureus was proven no more than in 6.3%. The highest values of all main components of milk were achieved within a relatively short time after kidding (April 2015). The average content of fat was 3.64 ± 0.52 g 100 ml-1, 3.17 ± 0.16 g 100 ml-1 of protein, 2.60 ± 0.06 g 100 ml-1 of casein, 4.56 ± 0.24 g 100 ml-1 of lactose, and 12.02 ± 0.80 g 100 ml-1 of solids. Average content of vitamin A was 0.27 ± 0.14 mg kg-1 and average content of vitamin E was 0.60 ± 0.34 mg kg-1. Content of vitamin E increased almost continuously during the lactation, and the content of vitamin A was significantly higher at the end of lactation. In lyophilized milk powder the average trace metal contents were 7.76 ± 0.92 g kg-1 Ca, 1.62 ± 0.26 g kg-1 Mg, 15.3 ± 1.43 g kg-1 K, 789 ± 111 mg kg-1 Na, 23.2 ± 2.73 mg kg-1 Zn, and 0.85 ± 0.55 mg kg-1 Cu. Contents of minerals varied during the lactation period, but no significant trends were observed. [ABSTRACT FROM AUTHOR]

Electrolytes in serum are important biomarkers for skeletal and cellular health. The levels of electrolytes are monitored by measuring the K, Ca, Mg and Na in blood serum. An accurate method for the determination of K, Ca and Mg in serum by taking advantage of the “cold” plasma mode and collision reaction cell of the isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) was developed. The three kinds isotope of 41K, 42Ca and 25Mg were added at the same time, while the contents of K, Ca and Mg were also measured. The proposed method can eliminate the need for a slow and tedious sample digestion procedure, and also can avoid the molecular ions interference. The national institute of standards and technology standard reference material 956c inorganic components in frozen human serum was analyzed by the method, and the measured elements values were in good accord with the standard values. [ABSTRACT FROM AUTHOR]

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Taken Feizixiao litchi fruits as tested materials, the effects of Ca and Mg applied in foliar nutrients on the pericarp ' s coloring by different treatments (including spraying the concentrations of 0.5 % KC1 (K) , 0.3 % CaCl2(Ca) , 1.5 % MgCl2(Mg) solutions and their mixtures) were studied, and spraying clean water was used as the check(CK). The results showed that with the growth and development of fruits under different treatments and CK # the values of h, the contents of the chlorophyll in pericaip and the acid in flesh decreased generally. The contents of the soluble sugar in flesh increased generally before May 19th. From May 19th to May 22th，the contents of the soluble sugar in flesh with the treatments of Ca + Mg and K + Ga + Mg presented no significant difference, while those with other, treatments were significantly decreased. The values of a > the contents of anthocyanin in pericaip and the ratio of sugar/acid in flesh increased generally. During the fruit mature period, the value of h in pericarp of the treatment Mg dropped to the bottom and was significantly lower than those of CK and the other treatments on May ，and the content of the soluble sugar in flesh of the treatment Ca + Mg maintained the highest content and was significantly higher than that of CK on May 22th , while k value of the treatment Ca + Mg made no significant difference from that of CK and was significantly lower than those of other treatments. So the synchronization of the values of h in pericarp and the contents of the soluble sugar in flesh of the treatments Mg and Ca + Mg achieved the best on May 19th and 22th，respectively. The treatment Mg successfully solved the problem that the peel kept green when the content of the soluble sugar in flesh rise to the top, and the treatment Ca + Mg successfully solved the problem that the content of the soluble sugar in flesh dropped when the pericarp color was full. [ABSTRACT FROM AUTHOR]

Introduction: To assess the salivary composition of proteins and minerals in smokers compared with non-smokers. Materials and Methods: In this study we compared the total protein and Ca, Na, K, Mg, Pb of whole saliva in two groups of men (28 smokers and 31 nonsmokers) aged between 29-41 years. Results: Fifty-nine participants were evaluated. The mean age was 33.14±5.32 years among smokers and 32.15±5.12 years among non-smokers (P>0.05). The mean concentration of total protein, Ca, Pb, and Zn of whole saliva in smokers was lower than that in non-smokers, but the difference was not statistically significant (P>0.05). The mean concentration of Na, K, Mg in whole saliva was not significantly different between smokers and non-smokers (P>0.05). Conclusion: We specified that smoking reduced the value of total protein, Ca and Pb of saliva, however it did not have an impact on Na, K, and Mg of saliva. [ABSTRACT FROM AUTHOR]

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Copyright of Archives of Environmental Protection is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. [ABSTRACT FROM PUBLISHER]

Abstract: K and Mg substituted perovskite catalysts La1−xKxCo1−yMgyO3 (x=0–0.4, y=0–0.2) for soot combustion were prepared by citric acid complexation and characterized by XRD, FT-IR, SEM, TEM, EDS, H2-TPR, XPS and TG. Soot combustion was remarkably accelerated when K was introduced into LaCoO3. Then Mg was doped into the K substituted LaCoO3, soot combustion was further improved for the restrained growth of Co3O4 phase. K/Mg substitutions were responsible for enhancing activity of catalysts by improving reducibility as suggested by H2-TPR studies. Among all the catalysts, La0.6K0.4Co0.9Mg0.1O3 exhibited the highest activity. [Copyright &y& Elsevier]

The relationship between alternate bearing and the variation of mineral nutrient content in the leaves and stems of ‘Kinnow’ mandarin trees (Citrus reticulataBlanco) and the effects of these relationships on flower bud formation were investigated. Mineral content was determined in the leaves and stems of “on” and “off”-year trees at 1-month intervals from November until March, coinciding with the floral bud formation stages of citrus trees. The results showed that the presence of fruits consistently inhibited flower bud formation, decreased the number of sprouting buds, and reduced the vegetative growth of trees. Fruiting state had a significant effect on the content of P, K, and Mg in both leaves and stems, but did not affect the amount of N in these two organs. Leaf and stem P and K contents were greater in “off” than in “on” trees, but Mg content was higher in “on” than in “off” trees. Mandarin fruits were acting as very strong sinks for potassium and phosphorous. Thus, K and P levels in “on” trees decreased to deficient levels, and therefore, a sufficient supply of these two elements is a key to a successful commercial annual production. Seasonal variations in leaf and stem micronutrient contents were neither uniform nor affected by the fruiting state of trees. [ABSTRACT FROM AUTHOR]

Tartary buckwheat ( Fagopyrum tataricum Gaertn.) contains protein of high nutritional value, polyphenols, vitamins and minerals. It is one of the most important minor crops in China and has a great potential as a health and functional food. However, information on the elemental mineral composition of its seeds remains limited. The concentrations of Cu, Zn, Fe, K, and Mg in seeds of 123 tartary buckwheat accessions from the same cultivation were studied by means of flame atomic absorption spectrometry. The results revealed that the average concentrations of Cu (x), Zn (x), Fe (x), K (x), and Mg (x) elements in the accessions are 19.49 (with a range of 5.74-36.01 mg/kg), 27.41 (8.44-66.63 mg/kg), 656.24 (21.8-3,990 mg/kg), 3,639.23 (1,737-5,831 mg/kg), and 1,523.89 mg/kg (729-3,104 mg/kg) respectively. Among them, Fe concentration has the highest coefficient of variation (114.7 %). The results also revealed five significant positive correlations among Cu, Zn, Fe, K, and Mg concentrations. Therefore, distinct genotypes with high concentration of mineral elements should be effective for the development of special buckwheat varieties and improvement of its food nutritional quality. [ABSTRACT FROM AUTHOR]

Electrolytes in serum are important biomarkers for skeletal and cellular health. The levels of electrolytes are monitored by measuring the Ca, Mg, K, and Na in blood serum. Many reference methods have been developed for the determination of Ca, Mg, and K in clinical measurements; however, isotope dilution thermal ionization mass spectrometry (ID-TIMS) has traditionally been the primary reference method serving as an anchor for traceability and accuracy to these secondary reference methods. The sample matrix must be separated before ID-TIMS measurements, which is a slow and tedious process that hindered the adoption of the technique in routine clinical measurements. We have developed a fast and accurate method for the determination of Ca, Mg, and K in serum by taking advantage of the higher mass resolution capability of the modern sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). Each serum sample was spiked with a mixture containing enriched Ca, Mg, and K, and the Ca:Ca, Mg:Mg, and K:K ratios were measured. The Ca and Mg ratios were measured in medium resolution mode (m/Δm ≈ 4 500), and the K ratio in high resolution mode (m/Δm ≈ 10 000). Residual ArH interference was still observed but the deleterious effects of the interference were minimized by measuring the sample at K > 100 ng g. The interferences of Sr at the two Ca isotopes were less than 0.25 % of the analyte signal, and they were corrected with the Sr intensity by using the Sr:Sr ratio. The sample preparation involved only simple dilutions, and the measurement using this sample preparation approach is known as dilution-and-shoot (DNS). The DNS approach was validated with samples prepared via the traditional acid digestion approach followed by ID-SF-ICP-MS measurement. DNS and digested samples of SRM 956c were measured with ID-SF-ICP-MS for quality assurance, and the results (mean ± expanded uncertainty in mg dL unit) for Ca (DNS = 10.14 ± 0.13, digested = 10.11 ± 0.10), Mg (DNS = 2.093 ± 0.008, digested = 2.098 ± 0.007), and K (DNS = 15.48 ± 0.11, digested = 15.50 ± 0.28) were in good agreement with the certified values (Ca = 10.17 ± 0.06, Mg = 2.084 ± 0.023, K = 15.55 ± 0.13). Major sources of uncertainty are sample measurement, spike calibration, and instrument factor including mass discrimination of the spectrometer and the detector deadtime. [ABSTRACT FROM AUTHOR]

Biological apatite is the main mineral phase of bone tissue and of numerous calcified pathological deposits. Mg, Na, and K are usually absent in the structure of pure apatite and are present in such biominerals in significant concentrations. In present work the approach was tested for the determination of predominant location of these elements through separation of apatite and non-apatitic components of bone tissue mineral. The preparation procedures include the annealing and subsequent ultrasonication of powdered material in aqueous medium; concentrations of elements were determined by atomic spectrum analysis. The results suggest that Mg and Na in bone apatite can be both in the structurally bounded (substituting calcium in lattice) and in the labile state (being localized on the crystal surface), while K is not able to join the apatite structure in significant amount or be chemically bounded to it. [ABSTRACT FROM AUTHOR]

Copyright of Listy Cukrovarnicke a Reparske is the property of VUC Praha a.s. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mineral imbalance in the body may significantly contribute to the development and course of hypertension. In this paper, blood pressure figures have been linked to the levels of Fe, Ca, Mg, Zn, Cu, Na and K in hair. The research sample was composed of young men ( n = 91) aged 13-21, from the town of Mafinga, Iringa District, Tanzania. The data collected included their age, tribal background and weekly diet. Based on body mass index, the participants were categorised into pre-defined subgroups. To examine how the minerals in question affect blood pressure, correlation analysis and multiple ridge regression analysis were performed. Analysis of ridge regression findings for the researched group ( n = 91) shows that the minerals under scrutiny account for systolic blood pressure variation in 13 % and in 15 % for diastolic blood pressure variation. After including two additional variables-calendar age and body mass index-in regression analysis, the ultimate coefficient of determination ( R) changes for systolic blood pressure and remains the same for diastolic blood pressure ( R = 0.194 and R = 0.156, respectively). Nutritional analysis shows that the students included in the study received insufficient calories per day (1,500-2,200 kcal). The group of students with abnormal blood pressure were not aware of their poor health. Research findings may result from progressive environmental changes and poor nutrition in terms of food quantity and quality, which had an impact on the subjects' blood pressure. Hair analysis used to determine mineral content in the body may be an auxiliary tool in identifying the links between factors leading to the development of hypertension. [ABSTRACT FROM AUTHOR]

Abstract: A fast and straightforward pre-concentration procedure based on solid phase extraction with a strongly acidic cation-exchanger Dowex 50W×8–400 was proposed to determine traces of Ca, K, Mg and Na in white sugar samples by means of flame atomic absorption spectrometry. For this purpose, 20% (m/v) white sugar solutions (100ml) were driven through resin beds at 10mlmin−1 to retain Ca, K, Mg and Na ions and to separate sucrose that passed through unretained. Thereafter, columns were rinsed with water and elements of interest were recovered prior to measurements using 5ml of a 2moll−1 HCl solution. Detection limits of 0.04, 0.05, 0.02 and 0.01μgg−1 for Ca, K, Mg and Na, respectively, and precision of measurements within 1–3% were achieved. The proposed method enabled to determine Ca, K, Mg and Na in samples of white sugar within corresponding ranges: 0.66–0.99μgg−1 (Ca), 2.9–12.2μgg−1 (K), 0.53–1.57μgg−1 (Mg) and 0.06–0.30μgg−1 (Na). Accuracy of this sample pre-treatment procedure and analysis method was assessed by performing spikes and recovery experiments. Recoveries of added Ca, K, Mg and Na were found to be within 97–102%, demonstrating good reliability of results. [Copyright &y& Elsevier]

Threshold levels of sodium, potassium, calcium, and magnesium that define the distribution range of roach in fresh water are 0.015-0.019, 0.012-0.015, 0.006-0.009, and 0.002-0.003 mmol/L, respectively. A reduction in water mineralization is accompanied by a significant decrease in the concentration gradient of cations between the organism of a fish and the environment and by the increased stress on the systems responsible for salty exchange. Many reservoirs are characterized by lower concentrations of potassium in the water than is needed for the success of the roach population. The survival of roach in these waterbodies depends on the amount of potassium consumed by fish with their food. A comparative analysis is performed to assess the threshold levels of cations for roach, two bivalve mollusk species, crayfish, and the filamentous algae Spirogyra. [ABSTRACT FROM AUTHOR]

An essential problem connected with plant production is the effectiveness of P, K, Ca, Mg and N uptake by plants from mineral fertilizers. It is a very significant problem because mineral components are an element contributing to the creation of the highest yields. One of the methods used to improve nitrogen and other mineral component utilization by plants from a mineral fertilizer dose is the use of "stay-green" maize cultivars. Cultivars of the "stay-green" type utilize nitrogen from mineral fertilizers to a higher degree compared to a traditional hybrid. The aim of this study was to determine the hierarchy of macro-elements in the creation of a generative yield supplied by the grain of two different maize cultivars. The results showed that higher contents of phosphorus and potassium in the dry matter of grain and a greater uptake with the grain dry matter yield were found with regard to nitrogen, phosphorus, potassium, magnesium and calcium for the hybrid LG 2244 "stay-green" type, in comparison to the traditional cultivar, Anjou 258. [ABSTRACT FROM AUTHOR]

Land use management is important to maximize nutrients use efficiency and reduce losses, especially on sandy soils. Nutrient cycling in pastoral systems is different as the grazing animals are excreting back to the pasture most of the ingested nutrients. The objective of this study was to evaluate N, P, K, Ca, Mg, and Na by monitoring elements' concentrations in soil solution from bahiagrass ( Paspalum notatum Flugge) pastures continually-stocked with cattle (CP) and rotationally-grazed by goats (GP) in comparison with arable land (AL). Samples were obtained by suction cup lysimeters randomly installed at three depths in an Ultisol of North Florida, USA. To evaluate nutrients in atmospheric deposition, surface and ground waters, samples from rain, nearby spring, lake and three wells on the farm were also analyzed. The results confirmed that land-use management had an effect on soil-solution N, P, K, Ca, Mg, and Na concentrations reflecting managerial and climatic conditions. The means of these nutrients ranged widely from 0.64 to 11.14 mg L for N, 0.03-0.45 mg L for P, 0.12-6.97 mg L for K, 0.37-33.91 mg L for Ca, 0.47-7.39 mg L for Mg, and 1.28-4.37 mg L for Na. The soil-solution N was higher from March through August (wet seasons) and lower and relatively constant between September and February (dry seasons). The N from shallow depth (0.6 m) of CP was fourfold higher than the deep (1.8 m) one and exceeded the maximum permissible level (MPL) of 10 mg L. A 1.5-fold increase by depth of AL was detected, and a leaching of 53-98 kg N ha was identified for both AL and CP during the wet season vs. 4-5 kg ha leachable N from GP. Also, a 1-3 kg P ha may be leached from CP during the wet season. The nutrients in the soil solutions tended to be higher than those in rain, lake, sprint, well, and tap waters. In groundwater however, there were episodically N concentrations as high as those in the soil solution. [ABSTRACT FROM AUTHOR]

nondestructive X-ray fluorescence technique has been developed to determine Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, Ba, and Pb in plants. The line element intensities were measured by an S4 Pioneer X-ray sequence spectrometer (Bruker AXS, Germany). The inversely proportional relationship was obtained between the analyte line intensity and mass of the plant, pressed on boric acid backing, for elements with an atomic number 11 < Z < 20. It was found that reduction of plant mass from 6 to 1 g leads to an increase in element determination sensitivity. The detection limits for 1 g of pressed plant were evaluated as μg/g: 5-20 (Na, Mg, Al); 1-4 (Si, P, S, Cl, K, Ca, Ti, Ba, Pb); 0.4-0.8 (Cr, Mn, Fe, Ni, Br, Cu, Zn, Rb and Sr). This technique was applied to determine the element composition of violets of Violaceae family, which are used in medicine. [ABSTRACT FROM AUTHOR]

Out of 100 microliters of capillary blood of 32 normotonic and 55 hypertonic (RR at least 140/100) diabetic patients, the following parameters were determined at 09:00 a.m.: pH, pCO2, baseexcess, HCO3, PO2, O2sat., Na, Ca, Mg, K, lactate and blood glucose. Group averages of the normotonic and hypertonic patients did not show any sign ificant differences in the parameters mentioned. But when we split the 2 groups along their glucose averages, forming 4 subgroups with higher and lower glucose levels, significant differences between Mg and K in the respective groups were evident, pointing towards an increase in electrolyte metabolism due to both hyperglycemia and hypertonia. Linear regressions between Mg, glucose and pH within the four groups increased circumstantial evidence for our supposition of increased electrolyte metabolism being attributable to both hyperglycemia and hypertonia, considerably. It turned out that high blood glucose alone already increases electrolyte metabolism, shown by positive correlations with Mg and glucose and negative correlations between Mg and pH which culminates in the highest Mg values along with highest glucose and lowest pH values in patients with combined hyperglycemia and hypertonia. Although we partly drew similar conclusions in a former paper [14], the step forward in the present work is that results won by comparison of parameter changing (delta values) between two sampling events can be confirmed by using the directly determined data of just a single sample. Thus, appropriately processed data and comparatively simple mathematical operations like implementation of linear regressions do not only detect significant differences hidden behind similar group averages, but also considerably curtail the necessary diagnostic blood sampling. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Elementology is the property of Journal of Elementology - issued by Polish Magnesium Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Temporal changes in the influent municipal sewage in the pH, Electric Conductivity, TDS, TSS, cations - Calcium (Ca), Magnesium (Mg), Hardness, Sodium (Na), monovalent Potassium (K) and anions - Chlorides (Cl-), Bicarbonates (HCO3 -) and alkalinity, assessed during Secondary Treatment in an extended aeration Activated Sludge Treatment Process (STP) plants at Kalpakkam (Tamil Nadu), a small town on the east coast of Indian peninsula, revealed that the average values of the aforesaid parameters were 6.5, 1320 (μs/cm), 560, 352, 31, 31, 193, 134, 38, 297, 178, 1.3 and 127 mg/L in the influent Raw Sewage (RS). These parameters, except CO32-) and alkalinity, assessed during Secondary Treatment in an extended aeration Activated Sludge Treatment Process (STP) plants at Kalpakkam (Tamil Nadu), a small town on the east coast of Indian peninsula, revealed that the average values of the aforesaid parameters were 6.5, 1320 (μs/cm), 560, 352, 31, 31, 193, 134, 38, 297, 178, 1.3 and 127 mg/L in the influent Raw Sewage (RS). These parameters, except CO3 and alkalinity increased by 40% and 22% in AT and by 63% and 44% in SC respectively. Some of these parameters showed significant spatial (pH, conductivity and Ca) and temporal (conductivity, TSS, Mg, hardness, K and Cl2- and alkalinity, were reduced with a Removal Efficiency (RE) of 7, 10, 27, 18, 13, 19, 24, 13, 18, 18 and 21% respectively at the Aeration Tank (AT) and by 12, 26, 35, 80, 32, 39, 24, 46, 53, 52 and 47% respectively in the Secondary Clarifier (SC) Treated Effluent (TE) of the STP. The CO3 2- and alkalinity increased by 40% and 22% in AT and by 63% and 44% in SC respectively. Some of these parameters showed significant spatial (pH, conductivity and Ca) and temporal (conductivity, TSS, Mg, hardness, K and Cl-) variations across different seasons in the influent RS and at AT and SC in the STP. [ABSTRACT FROM AUTHOR]

1. The leaf litter of tropical forests serves as a carbon sink, slows soil erosion and leaching, and is home to a large fraction of the forest's biodiversity. Standing leaf litter reflects the balance of litterfall and decomposition; both rates may be limited by element availability. We propose a mechanism for this regulation that assumes phosphorus limits metabolism in tropical soils, and that phosphorus limitation is more pronounced in faster growing organisms. 2. Leaf litter depth varied 16-fold (1·4–22·4 cm) across 28 forest stands in Panama and Peru and was deeper on sand vs. clay soils. Of five elements tested (N, P, K, Mg and Ca), the concentration of P in decomposing litter best predicted litter depth ( r2 = 0·76, C : P1·90). This relationship broke down in the most impoverished sandy soils. 3. These data are consistent with the hypothesis that the weathering of tropical soils limits the metabolism of microbes first and trees second, with decomposition and litterfall co-limiting litter depth in ecosystems with the least available phosphorus. This has implications for the dynamics of weathering: nutrient leaching may be regulated through negative feedback if deeper litter buffers soil from rainfall. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Elementology is the property of Journal of Elementology - issued by Polish Magnesium Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To explore the importance of 12 elements in litter production and decomposition, we fertilized 36 1600 m2-plots with combinations of N, P, K, or micronutrients (i.e. B, Ca, Cu, Fe, Mg, Mn, Mo, S, Zn) for 6 years in a lowland Panamanian forest. The 90% of litter falling as leaves and twigs failed to increase with fertilization, but reproductive litter (fruits and flowers) increased by 43% with N. K enhanced cellulose decomposition; one or more micronutrients enhanced leaf-litter decomposition; P enhanced both. Our results suggest tropical forests are a non-Liebig world of multiple nutrient limitations, with at least four elements shaping rates of litterfall and decomposition. Multiple metallomic enzymes and cofactors likely create gradients in the break down of leaf litter. Selection favours individuals that make more propagules, and even in an N-rich forest, N is a non-substitutable resource for reproduction. [ABSTRACT FROM AUTHOR]

This article presents the results from a study of the comparison of 2 lowland rivers: the Olobok and the Pilawa in southwest Poland polluted by urban, agricultural, and textile industry sewages. pH and concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Zn, nitrate, nitrite, ammonia, phosphate, and sulfate were measured in water samples and concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, N, Na, Ni, P, Pb, S, and Zn were measured in stream bottom sediments and in the aquatic macrophytes Elodea canadensis, Callitriche verna, Potamogeton crispus, Potamogeton natans, and Ceratophyllum demersum from the river Olobok and Elodea canadensis, Polygonum amphibium, Potamogeton crispus, and Veronica beccabunga from the river Pilawa. The matrix of concentrations of 16 elements in 27 plant samples of 7 species from 15 sampling sites of 2 rivers and concentrations of 15 elements and pH in water samples and 16 elements and pH in bottom sediment samples of these sites was submitted to numerical classification, which revealed that sampling sites from the rivers were differentiated by the value of factor 1 of principal component analysis (PCA), which was related to the pH of water, Ca, Cu, Mg, Mn, and Ni in water and Cd, Cr, Cu, Fe, K, Mg, Na, Ni, P, and S in bottom sediments. More polluted parts of both rivers were differentiated from less polluted parts by the value of factor 2 of PCA, which was related to Pb, Zn, and sulfates in water and Ca and Zn in bottom sediments. Macrophytes from the Olobok and Pilawa rivers were differentiated by the value of factor 1, which was related to Ca, Co, Cr, Cu, Fe, Mg, Ni, N, Na, Pb, and S. Groups of macrophytes of more and less polluted parts of both rivers differed by the value of factor 2, which was related to P, K, and Mn. Downstream of the sewage outputs in both rivers, a significantly increased level of pollution occurs with elements correlated with factor 1: Among others were Cu and Cr, typical for the textile industry along the river Pilawa, and among others were Mn and Ni, typical for the urban and agricultural activities in the river Olobok. [ABSTRACT FROM AUTHOR]

The objective of the experiment was to compare the concentration of some elements (Cu, Mn, Zn, Ca, Mg, K, Na, Fe) in chosen organs (liver, stomach, muscle, heart, lungs, kidneys, brain) in tree species of carnivorous fur animals (Polar foxes, Silver foxes, Raccoon dog). Elements were determined by the method of atomic absorption spectral photometry. Concentration of elements was assessed in milligram per kilogram dry matter (mg.kg-1). Obtained results were processed mathematically and statistically (SAS/STAT 1999&3x2013;2001). We compare concentration of each element between sexes within species. The most number of significant differences in all chosen organs were in Cu concentration. The lowest were in Mn and Fe concentration. The concentration of certain elements is higher in female or male in the definite organ and certain species in comparison with other species of the same family (e.g. liver, Cu concentration in female polar foxes was significant higher 23.77 mg.kg-1 than in the male ones 15.17 mg.kg-1 of the same species. On the other hand, liver, Cu silver foxes is higher in male 37.73 mg.kg-1 than in female ones 16.17 mg.kg-1 .In raccoon dog more Cu is found in male liver 25.50 mg.kg-1 than in female one 25.05 mg.kg-1. The difference is not significant. The significant differences in concentration of certain elements in all three species only were in Cu concentration in muscle, when higher concentration was in female of foxes species (polar fox female -9.73 mg.kg-1, polar fox male - 7.90 mg.kg-1 , silver fox female - 8.97 mg.kg-1 , silver fox male -7.63 mg.kg-1) and opposite situation was in raccoon dog - higher Cu concentration was in male (7.64 mg.kg-1) than in female one (7.44 mg.kg-1). [ABSTRACT FROM AUTHOR]