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... Human transferrin (Tf) very tightly binds two ferric ions to deliver iron to cells. Fe(III)₂Tf (Fe₂Tf) binds to the Tf receptor (TfR) at pH 7.4; however, iron-free Tf (apoTf) does not. Iron uptake is facilitated by endocytosis of the Fe₂Tf-TfR complex. Tf can also bind aluminum ions, which cause toxic effects and are associated with many diseases. Since Al(III)₂Tf (Al₂Tf) does not bind to TfR, the ...
Fourier transform infrared spectroscopy; Lewis bases; aluminum; amination; ammonia; benzene; carboxylic acids; combustion; green chemistry; hydrides; isothiocyanates; lithium; nuclear magnetic resonance spectroscopy; pollen; spores; sporopollenin
Abstract:
... Sporopollenin, which is a naturally occurring and highly resilient organic polymer constituting the external shell of spores and pollen grains, has been converted into a primary amine form with a loading of 0.58 ±0.04 mmol.g⁻¹ by reductive amination with ammonia and lithium aluminium hydride successively. The presence of the amine and precursor amide groups were established by combustion elemental ...
agricultural soils; soil pH; soil solution; aluminum; chemical speciation; soil depth; soil organic matter; phytotoxicity; dissolved organic carbon; bioavailability; liming; field experimentation; climatic factors; liming materials; application rate; base saturation; soil weathering; molecular weight; organic compounds; Brazil
Abstract:
... Aluminum toxicity is one of the major soil factors limiting root growth in acidic soils. Because of the increase in organic matter content in the upper few centimeters of soils under no-till systems (NTS), most Al in soil solution may be complexed to dissolved organic C (DOC), thus decreasing its bioavailability. The aim of this study was to evaluate the effects of surface liming on Al speciation ...
... We tested the potential for arbuscular mycorrhizal fungi to mediate plant adaptation to mine soil conditions utilizing a full factorial experiment involving two fungal communities, two ecotypes of plants and two soil types. We found that plants grew larger with fungal communities derived from mine soil regardless of the soil type in which they were grown. There was no evidence that the plants suff ...
aerosols; air quality; aluminum; ammonium sulfate; cadmium; calcium; carbon; carbonates; chemical composition; combustion; heat treatment; ions; iron; lead; manganese; nickel; sodium; spring; summer; traffic; Northern Africa
Abstract:
... This study examines the chemical composition of aerosols over the Greater Istanbul Area. To achieve this 325 (PM₁₀) aerosol samples were collected over Bosphorus from November 2007 to June 2009 and were analysed for the main ions, trace metals, water-soluble organic carbon (WSOC), organic (OC) and elemental carbon (EC). PM₁₀ levels were found to be in good agreement with those measured by the Ista ...
... Aluminium (Al) toxicity and drought are the two major abiotic stress factors limiting common bean production in the tropics. Using hydroponics, the short-term effects of combined Al toxicity and drought stress on root growth and Al uptake into the root apex were investigated. In the presence of Al stress, PEG 6000 (polyethylene glycol)-induced osmotic (drought) stress led to the amelioration of Al ...
... The concept, design and performance analysis of a four-stage novel constructed wetland system (CWs) capable of enhanced and simultaneous removal of phosphorus (P) and organic matter (OM) from wastewaters is described. Alum sludge, a largely available by-product of drinking water facilities using aluminium salts as coagulant was used as the media. Under a hydraulic loading rate of 1.27m³/m² d and a ...
human diseases; hemodialysis; quantitative analysis; at-risk population; calcium; antacids; strontium; dietary exposure; aluminum; patients; mineral content; dietary mineral supplements
Abstract:
... Trace elements, most notably aluminium and strontium, have been noted for their role in the development of secondary bone disorders in haemodialysis patients. Due to the large dosages of calcium required for the maintenance of dialysis patients, this study investigated whether the source of calcium chosen for supplementation, including the form of administration (i.e. chewable forms or capsules), ...
... The negative effects of elevated concentrations of inorganic aluminium on aquatic organisms are well documented. Acid deposition is often cited as a main driver behind the mobilisation and speciation of aluminium in soils and surface waters. In the study, we tested the hypothesis that sulphur deposition is the main driver for elevated concentrations of inorganic aluminium in 114 base poor, boreal ...
... Aluminium gives beer a metallic and bitter flavour without any observations on particular aroma compound changes. Besides it has lately been implicated as one of the possible causal factors contributing to Alzheimer's disease. A highly sensitive, selective, rapid, reliable and inexpensive method has been used for direct analysis of free aluminium in thirty-nine samples of bottled lager beer. Diffe ...
... Purpose Aluminium partitioning in the solid fraction and aluminium in solution in the bulk and rhizospheric soil of different plant species colonising an abandoned Cu mine slope (Calluna vulgaris, Erica cinerea and Salix atrocinerea) and mine dump (C. vulgaris and E. cinerea) were investigated. The aim of the study was to determine the changes that the species induce in the Al forms in the rhizosp ...
... Aluminium ions (Al) have been recognized as a major toxic factor for crop production in acidic soils. This study aimed to assess the impact of Al on the activity of phosphatidylcholine-hydrolysing phospholipase C (PC-PLC), a new member of the plant phospholipase family. We labelled the tobacco cell line BY-2 and pollen tubes with a fluorescent derivative of phosphatidylcholine and assayed for patt ...
... Aluminium is well known to inhibit plant elongation, but the role in this inhibition played by water relations remains unclear. To investigate this, tobacco (Nicotiana tabacum L.) suspension-cultured cells (line SL) was used, treating them with aluminium (50 μM) in a medium containing calcium, sucrose, and MES (pH 5.0). Over an 18 h treatment period, aluminium inhibited the increase in fresh weigh ...
aluminum; catalytic activity; chemical reactions; ligands
Abstract:
... A new aluminium complex bearing a dianionic phenylene-diamine based ligand has been synthesized and shown to catalyze the intramolecular hydroamination of various aminoalkenes. ...
... Aluminium (Al) is phytotoxic when solubilized into Al³⁺ in acidic soils. One of the earliest and distinct symptoms of Al³⁺ toxicity is inhibition of root elongation. To decipher the mechanism by which Al³⁺ inhibits root elongation, the role of ethylene and auxin in Al³⁺-induced inhibition of root elongation in Arabidopsis thaliana was investigated using the wild type and mutants defective in ethyl ...
... Aluminium (Al) rhizotoxicity coincides with low pH; however, it is unclear whether plant tolerance to these two factors is controlled by the same mechanism. To address this question, the Al-resistant alr104 mutant, two Al-sensitive mutants (als3 and als5), and wild-type Arabidopsis thaliana were compared in long-term exposure (solution culture) and in short-term exposure experiments (H⁺ and K⁺ flu ...
... Humic substance could control the activity of metal as well as exchangeable aluminum(Alexch) on acid soil. The humic substance extracted from compost of agricultural waste is rarely conducted. Theobjective of research was to evaluate the effect of humic substance concentration and sources to pH and Al suspension.The research had been conducted in the Soil Laboratory of Agricultural Faculty of Jemb ...
... This study describes the aluminum (Al) accumulation in relation to macronutrient and micronutrient elements in 19 Melastomataceae species in the Guayana Region in Venezuela. The purpose was to investigate the Al accumulation in four tribes and different life forms. Aluminum accumulation was predicted in the basal tribes Miconieae and Merianieae in contrast to the derived tribes and herbs from any ...
at-risk population; bioaccumulation; Food and Drug Administration; food contamination; parenteral feeding; dietary exposure; aluminum; patients; toxicity; pharmacokinetics; United States
Abstract:
... In July 2004, the U.S. Food and Drug Administration issued a mandate that required manufacturers to include the aluminum content on the labels of the additives commonly used in the compounding of parenteral nutrition solutions. It was the hope that practitioners would use this information to minimize the amount of aluminum exposure provided by parenteral nutrition to less than the 5 mCg/kg/d, the ...
... Aluminum (Al) exists naturally in air, water, and soil, and also in our diet. Al can be absorbed into the human body and accumulates in different tissues, which has been linked to the occurrence of Alzheimer's disease and various neurological disorders. By using Vicia cytogenetic tests, which are commonly used to monitor the genotoxicity of environmental pollutants, cytogenetic effects of aluminum ...
... Two common bean (Phaseolus vulgaris L.) genotypes differing in aluminum (Al) resistance, Quimbaya (Al-resistant) and VAX-1 (Al-sensitive) were grown in hydroponics for up to 25 h with or without Al, and several parameters related to the exudation of organic acids anions from the root apex were investigated. Al treatment enhanced the exudation of citrate from the root tips of both genotypes. Howeve ...
... The formation of radical species was examined in roots of soybean seedlings exposed to aluminum (Al). Electron spin resonance (ESR) spectra of root homogenates with the spin-trapping reagent 5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO) indicated the presence of carbon-centered radicals in plants not exposed to Al. Plants exposed to 50 μM Al showed a similar spectrum, with increased s ...
... The response of the antioxidant enzymes, superoxide dismutase (SOD; EC 1.15.1.1) and peroxidase (POD; EC 1.11.1.7), to Aluminum (Al) stress was studied in roots of two inbred lines of maize (Zea mays L.) differing in their tolerance to Al. In addition, the production of malondialdehyde (MDA) was measured to evaluate the level of lipid peroxidation as well as the accumulation of proline (Pro) and c ...
... Waterlogging results in high shoot concentrations of iron (Fe), aluminum (Al), and manganese (Mn) in wheat grown in acidic soil. The verification of this observation in several acidic soils, development of screening techniques, and identification of genotypes differing in tolerance made it possible to test whether tolerance of ion toxicities improves performance of wheat in waterlogged acid soils. ...
... Low-pH and Al³⁺ stresses are the major causes of poor plant growth in acidic soils. However, there is still a poor understanding of plant responses to low-pH and Al³⁺ toxicity. Low-pH or combined low-pH and Al³⁺ stress was imposed in order to measure rhizosphere pH, ion fluxes, plasma membrane potential and intracellular H⁺ concentration in distal elongation and mature zones (MZs) along the longit ...
... Several studies of fish have shown that aluminum may induce hypoxia, hypercapnia, metabolic acidosis, and respiratory failure. In lymphocytes, morphologic abnormalities and reduced immune activity have been observed. Nevertheless, there is little data on oxidative stress and such data are essential in order to identify its mechanism of action. The common carp Cyprinus carpio, an omnivorous fish co ...
aluminum; calcium; chlorides; cluster analysis; magnesium; multivariate analysis; nitrates; potassium; semiarid zones; sodium; sulfates; temporal variation; water hardness; watersheds; Brazil
Abstract:
... Entre os grandes desafios na gestão da qualidade das águas pode-se citar o elevado custo do monitoramento e a alta variabilidade espacial e temporal dos elementos determinantes da qualidade da mesma. Sendo assim, desenvolveu-se um estudo para identificar a similaridade das águas subterrâneas da bacia do Banabuiu com o objetivo de oferecer suporte ao monitoramento e a gestão da qualidade da água no ...
... In this study, freshly deposited soils were sampled from the Seyhan River (Turkey) from the exit of the Seyhan Dam to the Adana exit. Heavy metal contents were measured with X-ray fluorescence spectrometer. Multivariate statistical approach is used to identify the sources of heavy metals and other elements in soil samples. Considering the size of anomalies, metals are ranked as Co>Pb>Cr>Zn>Al. Bas ...
... Tehran is one of the megacities of the world with a population of over eight million. Its air is highly polluted mainly due to the suspended particulate matters, which encompasses a wide spectrum of chemical elements. These elements based on their type, size, and impact on the life cycle have various environmental and health risks. In this research, the neutron activation method is used to determi ...
... At present, anthropogenic contribution of heavy metals far exceeds natural input in some aquatic sediment, but the proportions are difficult to differentiate due to the changes in sediment characters. In this paper, the metal (Al, Fe, K, Mg, Ca, Cr, Cu, Ni, and Zn) concentrations, grain size, and total organic carbon (TOC) content in the surface and core sediments of Nansihu Lake Catchment (the op ...
... Background, aims, and scope Heavy metal contaminants in environment, especially in drinking water, are always of great concern due to their health impact. Due to the use of heavy metals as catalysts during plastic syntheses, particularly antimony, human exposure to metal release from plastic bottles has been a serious concern in recent years. The aim and scope of this study were to assess metal co ...
... Aluminum (Al) toxicity is a major worldwide constraint to crop productivity on acidic soils. Al becomes soluble at low pH, inhibiting root growth and severely reducing yields. Maize is an important staple food and commodity crop in acidic soil regions, especially in South America and Africa where these soils are very common. Al exclusion and intracellular tolerance have been suggested as two impor ...
... Stomatal pores formed by a pair of guard cells in the leaf epidermis control gas exchange and transpirational water loss. Stomatal closure is mediated by the release of potassium and anions from guard cells. Anion efflux from guard cells involves slow (S‐type) and rapid (R‐type) anion channels. Recently the SLAC1 gene has been shown to encode the slow, voltage‐independent anion channel component i ...
aerosols; air; aluminum; ammonia; ammonium nitrate; atmospheric deposition; biogeochemistry; chemical composition; ions; lead; mass transfer; seawater; sodium; summer; zinc; Korean Peninsula; Sea of Japan
Abstract:
... Atmospheric deposition of different types of aerosols over the southern East Sea has received little attention in terms of seawater biogeochemistry. We investigated the concentrations of water-soluble ions (NO₃ ⁻, NH₄ ⁺ and nss-SO₄ ²⁻) in the aerosols associated with air mass transport patterns arriving at the east coast of Korea, adjacent to the southern East Sea, in order to determine source reg ...
... Soil acidity can have a potent influence on soil microbial composition and function, but it remains unclear if this influence is a direct response to the concentration of H⁺ or an indirect response caused by the influence of pH on other soil chemical properties. We hypothesized that the composition and function of soil microorganisms would shift in response to decreases in the availability of inor ...
alkalinity; aluminum; aluminum oxide; ammonium chloride; application rate; buffering capacity; ecosystems; fractionation; hydrochloric acid; iron; leaching; nutrient availability; pH; phosphorus; sand; sodicity; sodium hydroxide; temperature; wastes; water content; water holding capacity; Western Australia
Abstract:
... Background, aim and scope The production of alumina involves its extraction from bauxite ore using sodium hydroxide under high temperature and pressure. This process yields a large amount of residue wastes, which are difficult to revegetate due to their inherent hostile properties—high alkalinity and sodicity, poor water retention and low nutrient availability. Although phosphorus (P) is a key ele ...
... α-Amylase activity was screened in the peel, as waste fruit, of 13 species and cultivars of Egyptian citrus. The species Citrus sinensis cv. Abosora had the highest activity. α-Amylase AI from Abosora peel was purified to homogeneity using anion and cation-exchange, and gel filtration chromatographies. Molecular weight of α-amylase AI was found to be 42 kDa. The hydrolysis properties of α-amylase ...
... This paper discusses the synthesis of biodiesel catalyzed by solid base of K₂CO₃/HT using Jatropha curcas oil as feedstock. Mg-Al hydrotalcite was prepared using co-precipitation methods, in which the molar ratio of Mg to Al was 3:1. After calcined at 600 °C for 3 h, the Mg-Al hydrotalcite and K₂CO₃ were grinded and mixed according to certain mass ratios, in which some water was added. The mixture ...
... The solid base catalyst KF/Ca–Al hydrotalcite was obtained from Ca–Al layered double hydroxides and successfully used in the transesterification of methanol with palm oil to produce biodiesel. With the load of KF, the activity of Ca–Al mixed-oxides had been improved much. For the mass ratio 80 wt.%(KF·6H2O to Ca–Al mixed-oxides) catalyst, under the optimal condition: 338 K, catalyst amount 5%(wt./ ...
... In this paper, the cadmium distribution in Certej River sediments in an area seriously affected by intense mining activities has been studied. The main objective of this study was the evaluation of partition of this metal into different operational defined fractions by sequential extractions. Community Bureau of Reference (BCR) sequential extraction was used to isolate different fractions. The sed ...
X-ray diffraction; alkalinity; aluminum; apatite; biocompatible materials; body fluids; calcium; calcium hydroxide; calcium silicate; energy-dispersive X-ray analysis; in vitro studies; nuclear magnetic resonance spectroscopy; osteoblasts; polymers; scanning electron microscopy; silicon; stable isotopes; transcription (genetics); tricalcium phosphate
Abstract:
... In vitro studies are reported of the behaviour of potassium aluminosilicate inorganic polymers containing 10 wt% Ca(OH)₂, nanostructured calcium silicate and Ca₃(PO₄)₂ exposed to simulated body fluid (SBF). Heating to 600 °C lowers the alkalinity of Ca₃(PO₄)₂-containing samples, but their X-ray powder diffraction characteristics, ²⁷Al, ²⁹Si and ⁴³Ca MAS NMR spectra are unchanged by heating. Exposu ...
Acacia mangium; aluminum; cerrado; coma; exchangeable aluminum; farms; forestry; humidity; pH; particle size; phosphorus; savannas; sodium; soil density; soil organic matter; soil water content; water content; Brazil
Abstract:
... Os quarenta mil quilômetros quadrados de savana (cerrado) em Roraima vêm sendo substituídos por agricultura, pecuária e florestamento, portanto, objetivou-se avaliar o efeito da conversão da savana nativa para plantios de Acacia mangium, com diferentes idades, em diferentes classes de solos e profundidades dos solos nas características químicas, físicas e no teor de água do solo. O trabalho foi co ...
sediments; chemical concentration; manganese; nuclear magnetic resonance spectroscopy; soil mineralogy; calcium; iron; EDTA (chelating agent); soil analysis; pretreatment; aluminum; extraction; phosphorus; mineral content; chemical structure
Abstract:
... Pretreatment with chemicals such as ethylenediaminetetraacetic acid (EDTA) is often used to improve the analysis of sediment P with solution P-31 nuclear magnetic resonance spectroscopy (³¹P-NMR), but there is a lack of a comprehensive assessment of the methodology. In this study, the effects of EDTA pretreatment on sediment P extracted using a mixture of 0.25 mol L⁻¹ NaOH and 50 mmol L⁻¹ EDTA (Na ...
... High bulk extracellular phosphatase activity (PA) suggested severe phosphorus (P) deficiency in plankton of three acidified mountain lakes in the Bohemian Forest. Bioavailability of P substantially differed among the lakes due to differences in their P loading, as well as in concentrations of aluminum (Al) and its species, and was accompanied by species-specific responses of phytoplankton. We comb ...
... Biochar properties can be significantly influenced by feedstock source and pyrolysis conditions; this warrants detailed characterisation of biochars for their application to improve soil fertility and sequester carbon. We characterised 11 biochars, made from 5 feedstocks [Eucalyptus saligna wood (at 400°C and 550°C both with and without steam activation); E. saligna leaves (at 400°C and 550°C with ...
... Heat stress relief for sows in hot and humid climates remains a challenge. This study investigates a cooling method that is intended to enhance heat dissipation from sows. The experimental device was an aluminium cover (1.5 m long by 0.65 m wide and either 0.8 m or 0.95 m high) fitted with water-cooled pipes (25 mm diameter, spaced at 100 mm, 150 mm or 200 mm) and attached to the frame of the gest ...
... The concentrations of aluminium, barium, calcium, copper, iron, magnesium, manganese, nickel, phosphorus, potassium, sodium, strontium, sulphur and zinc in white, green, black, Oolong and Pu-erh teas have been determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Samples were microwave-digested and the performance characteristics of the method were verified by analysing ...
Achyrocline satureioides; aerial parts; aluminum; cluster analysis; common names; discriminant analysis; emissions; food plants; functional foods; iron; magnesium; medicinal properties; mineral content; principal component analysis; raw materials; spectroscopy; sulfur
Abstract:
... Introduction - The chemometric characterisation of two plants frequently used as food and medicinal species, Achyrocline satureioides and Achyrocline venosa (Asteraceae: Gnaphalieae), was carried out based on their mineral composition. Both species, known by the common name of ‘marcelas', are very similar in their morphological features but they have different medicinal and food properties. Object ...
... As of 2007, of the 2,000 United States foundries, 93% produce ferrous or aluminum castings, generating 9.4 million tons of non-hazardous spent foundry sand (SFS) annually. Only 28% of the SFS is beneficially used. The U.S. EPA Resource Conservation Challenge identifies SFS as a priority material for beneficial use, with soil blending as a potential reuse option. The objectives of this work were to ...