High Iron Content Research Articles

Study of metallisation of titanomagnetite burnt pellets

To efficiently process titanomagnetite deposits in the Urals, new technological solutions must be developed. One such solution is the production of metallized titanomagnetite pellets, followed by electric smelting. Modern electric smelting technologies have strict requirements for the materials used, including a metallization degree above 90%, high metallic iron content (>85%), low FeO content (<1%), and high compression strength. This article explores the potential for producing metallized pellets suitable for further processing into electric arc furnace smelting or for HBI production from enriched concentrates of Gusevogorsky and Pervouralsky deposits under laboratory conditions. The scheme for enriching the poor concentrate of Pervouralskydeposithas been developed. The study analyzed the chemical, phase, and mineralogical compositions of the obtained concentrates. The results showed that the total iron content after beneficiation was more than 65% for both deposits. The study concluded that titanomagnetite iron ore raw materials are suitable for the metallization process. The degree of metallization of burnt pellets, after reduction by gas of CO+N2 composition (90/10%) at exposure (240 min), reached 92% and higher.

Use of Different Iron Preparations for Prophylaxis and Effects on Iron Status in Infancy.

Aim: To evaluate using different iron preparations for iron deficiency and/or iron deficiency anemia prophylaxis in infants and their iron status. Methods: In this study, we retrospectively evaluated the electronic patient records of 651 healthy children aged 9 to 13 months who met the inclusion criteria and who were followed up in pediatric follow-up outpatient clinics between January 2023 and June 2023. Results: A total of 651 children with a mean age of 11.2 ± 1.4 months, 54.7% of whom were boys, who met the inclusion criteria were included in the study; 56.5% of the children were using Fe + 3 salt and the others were using Fe + 2 salt, microencapsulated iron, or sucrosomial iron drops. After the fifth month of prophylaxis, when the effects of the iron preparations used on the mean laboratory values were evaluated, it was found that hemoglobin, serum iron, and ferritin levels were lower in sucrosomial iron and microencapsulated iron users compared to other preparations (p = 0.001). When statistically pairwise comparisons were made between the groups, hemoglobin and serum iron values were found to be lower in the group using sucrosomial iron compared to the groups using Fe + 2 and Fe + 3 salts (p < 0.0001). Hemoglobin and ferritin levels were higher in the group using Fe + 2 salt compared to both sucrosomial iron and microencapsulated iron groups (p < 0.0001). When the infants were evaluated according to iron status, it was found that 208 (31.9%) had iron deficiency. Iron deficiency was found to be less in infants of families who defined their economic status as rich and in infants who used iron regularly (p-values 0.044 and 0.001, respectively). Iron deficiency/iron deficiency anemia was observed at a higher rate in the group using sucrosomial iron and microencapsulated iron prophylaxis (p = 0.001). Conclusions: To prevent iron deficiency, it is very important to use appropriate iron preparations for prophylaxis and to feed foods with high iron content. Although we found that families were willing to use different iron preparations other than iron salts for their infants, the results presented herein indicate that the rate of iron deficiency was lower in patients using iron salts. However, randomized controlled studies are needed to determine whether these preparations are effective in iron prophylaxis in infants.

A review on the phytochemistry and biological activities of Curculigo latifolia Dryand ex. W.Aiton

Curculigo latifolia Dryand. ex W. T. Aiton, from the genus Curculigo, is a medicinal plant traditionally used to treat numerous illnesses such as fever, stomach aches, jaundice, wounds, and inflammation. C. latifolia is a perennial herb that is widely found in tropical and subtropical regions, such as Southeast Asia, Southern China, Bangladesh, Australia, and the Andaman Islands. This review collates the reported studies on the different aspects of C. latifolia from its plant description, nutritional value, phytochemistry, chemical composition, and pharmacological properties. This review aims to identify gaps in the literature and provide useful references for future work on this plant. Previous studies have shown that C. latifolia contains high mineral contents of calcium, iron, and magnesium, which are essential components of human health. Moreover, the plant is rich in phytochemicals, which play a prominent role in various pharmacological activities. The most common compounds identified included curculigoside, crassifoside I, nyasicoside, and curculigine. C. latifolia demonstrated high antioxidant activity through its ability to scavenge superoxide anions, 1,1–diphenyl–2–picrylhydrazyl (DPPH) and 2,2’-azino–bis(3–ethylbenzthiazoline–6–sulfonic acid) (ABTS) radicals, reducing ferric ions to ferrous complexes, iron chelation, and B-carotene bleaching. It was also shown that the roots, stems, and leaves of C. latifolia were effective in exerting antimicrobial activity against several microbial strains, including Bacillus cereus, Bacillus subtillis, Enterobacter aerogenes, Erwinia sp., Klebsiella sp., Pseudomonas sp., Candida albicans, Salmonella choleraesuis and Staphylococcus aureus. Moreover, the root, fruit, leaf, petiole, and rhizome extracts were found to improve glucose uptake and insulin secretion in diabetic rats, suggesting their antidiabetic potential. C. latifolia presents a wide range of medicinal properties that could make it a promising functional food or source of food supplements to prevent nutrition–related or chronic diseases.

Blood from a stone: Do the trace metals of sperm whale coproliths reveal a contribution from squid haemolymph?

BackgroundAmbergris is a coprolith produced by some sperm whales (∼1 %). It has been hypothesised that the metals in ambergris derive from the haemolymph of squid in the whale diet (mainly copper). However, few data exist.We report analysis of 10 trace metals in each of 50 ambergris samples by inductively coupled plasma-mass spectrometry. Main FindingsAcid digests of the samples contained ∼5 to >6880 µg g−1 air-dried weight total metals; mainly of iron (present in ∼90 % of samples, 38), copper (∼95 % of samples, 40), zinc (93 % of samples, 39) and cadmium (∼95 % of samples, 40). ConclusionsWe suggest the variable and sometimes high concentrations of iron may reflect traces of haemoglobin or myoglobin from the whales. There may be other sources.The other major metals (Zn, Cu, Cd) are those also reported in several squid species. The distributions are unlike those of squid haemolymph alone, reportedly dominated by copper, or those of the sperm whale (e.g., skin), dominated by zinc.

Iron in Drinking Water and its Impact on Human Health –A Study in Selected Units of Jalalabad Cantonment

Background: Prevalence of diseases due to appearance of excessive amount of iron in drinking water is increasing day by day. Often people are unaware about the harmful effects of excess iron that may be present in drinking water. Sometimes they overlook minor symptoms. Adequate study was not conducted before to rule out actual scenario. The aim of this study is to represent the detrimental effect of excessive iron in drinking water as well as to create awareness to get rid of it. Methods: A cross-sectional study was carried out in 17 units of 17 Infantry Division, Jalalabad Cantonment, Sylhet covering the period of January 2019 to May 2019. Total 52 participants were selected purposively who had been suffering from various kinds of abdominal symptoms; their source of drinking water was marked. Water was collected from 5 different sources to see iron level. Again they were monitored after establishing Reverse Osmosis water filter. Iron level at drinking water was also tested each time at laboratory by Atomic Absorption spectrometry method. Informed written consent was taken from the patients. A semi-structured questionnaire was developed and data were collected by face to face interview. Analysis was done by using Statistical Package for the Social Sciences (SPSS version 25). Results: Among 52 respondents, maximum i.e. 25(48.07%) developed moderate to severe constipation followed by 16(30.76%) developed dyspepsia and while others i.e.11(21.15%) had both the symptoms. Symptoms were most severe among the persons who used to drink water having highest concentration of Iron (1.9 mg/L). After establishment of Reverse Osmosis water purifier the iron concentration in water reduced significantly and only 4(8%) had constipation and 6(12%) had dyspepsia. Conclusion: Iron is a natural constituent of drinking water. But considering the harmful impact of excessive iron present in drinking water to human health, regular monitoring should be ensured to identify the risk group. Bangladesh Armed Forces Med J Vol 56 No (2) December 2023, pp 58-64

EFFECT OF PROCESSING METHODS ON NUTRIENT ANDANTINUTRIENT COMPOSITION OF JUSTICIA SECUNDA LEAVES

Justicia secunda as a medicinal plant belongs to the family of Acanthaceae ,the leaf is an under-utilized medicinal vegetable that is believed and utilized as blood tonic by the local people and especially among the sect of some religious people that refuse blood infusion in medical conditions. This study examined the effect of processing methods on the nutrient and phytochemical composition of justicia secunda leaves. The leaves were subjected to blanching pre-treatment before sun drying for 72 hrs oven drying at 55 0C for 48 hrs and air drying for 120 hrsThe proximate, vitamins, minerals and phytochemical analysis were conducted on the samples using standard procedures. The results varied significantly (p&lt;0.05) in all the parameters measured according to the different processing treatments. Proximate composition of the samples ranged for crude protein (18.20-21.73%), crude fat (7.80-9.10%), crude fibre (12.00-14.90%), ash (15.50-17.40%), moisture (8.00-9.00%) and carbohydrate (27.98-35.50%). Mineral composition ranged for calcium (18.20-34.10 mg/100g), magnesium (47.11-54.29 mg/100g), sodium (126.43-136.47 mg/100g), potassium (425.49-453.03 mg/100g), phosphorus (135.40-145.76 mg/100g) and iron (33.07-38.94 mg/100g). Vitamin composition showed that thiamine (B1) ranged from 0.04-0.31 mg/100g, riboflavin (B2) (0.21-1.7 8mg/100g), niacin (B3) (0.49-1.89 mg/100g), vitamin C (6.31-19.48 mg/100g), while vitamin E ranged from (1.97-6.78 mg/100g). Anti-nutrient contents ranged for tannin (4.82-16.89 mg/100g), phenol (7.41-19.23 mg/100g), alkaloids (2.05-7.07 mg/100g) flavonoids (4.90-9.85 mg/100g) and saponin (3.25-8.35 mg/100g. Overall, the results revealed that air drying methods retained greater concentrations of fibre, minerals, vitamins and anti-nutrients than other processing methods. The high micro-nutrient contents of iron, anti-nutrient compounds and B group of vitamins in this processed vegetable reveals why it is used intuitively by the traditional people to boost health conditions due to the functional roles of iron, phytonutrients and B group of vitamins in heamopoisis in preventing morbidity and mortality especially among children.

Transferrin Immobilized Graphene Oxide Nanocomposite for Targeted Cancer Chemodynamic Therapy via Increasing Intracellular Labile Fe2+ Concentration.

Recently, different alternative regulated cell death (RCD) pathways, viz., necroptosis, pyroptosis, ferroptosis, cuproptosis etc., have been explored as important targets for the development of cancer medications in recent years, as these can change the immunogenicity of the tumor microenvironment (TME) and will finally lead to the inhibition of cancer progression and metastasis. Here, we report the development of transferrin immobilized graphene oxide (Tfn@GOAPTES) nanocomposite as a therapeutic strategy toward cancer cell killing. The electrostatic immobilization of Tfn on the GOAPTES surface was confirmed by different spectroscopy and microscopy techniques. The Tfn immobilization was found to be ∼74 ± 4%, whereas the stability of the protein on the GO surface suggested a robust nature of the nanocomposite. The MTT assay suggested that Tfn@GOAPTES exhibited cytotoxicity toward HeLa cells via increased lipid peroxidation and DNA damage. Western blot studies resulted in decreased expression of acetylation on lysine 40 of α-tubulin and increased expression of LC3a/b for Tfn@GOAPTES treated HeLa cells, suggesting autophagy to be the main cause of the cell death mechanism. Overall, we predict that the present approach can be used as a therapeutic strategy for cancer cell killing via selective induction of a high concentration of intracellular iron.

Use of metakaolin with a low surface area and rich in quartz and iron as a precursor in the production of structural alkali-activated concrete

Pumpable and machineable alkali-activated structural concretes are made using low-reactivity metakaolin with high quartz and iron contents. The effects and interaction of alkaline concentration (NaOH - 8, 10, 12, 14, and 16 M) and ratio of alkaline reagents (Na2SiO3/NaOH - 1.0, 1.5, 2.0, 2.5, and 3.0) on their properties were accessed using 2k complete factorial design. Higher concentrations of alkaline solutions resulted in faster hardening, decreased material deformation, and increased mechanical strength, with higher elastic modulus, lower damping, lower water absorption, and porosity. With time, the elastic modulus increased, and the dynamic damping decreased, suggesting the homogeneous formation of alkaline-activated products, confirming the proper configuration of the hardening process. The factorial design allowed for determining the ideal dosage for producing the material, indicating that the alkaline concentration (NaOH) should be 10 M and the Na2SiO3/NaOH ratio should be 2.5. They analyzed the possible combinations that allowed obtaining a material with adequate characteristics for the structural application.

Influence of intermetallic phase (TiFe) on the microstructural evolution and mechanical properties of as-cast and quenched Ti–Mo–Fe alloys

This study presents the phase analysis, microstructural characteristics, and mechanical property evaluation of the as-cast and quenched Ti–15Mo–xFe alloys with high iron content ranging from 4 to 12 weight percent. All the four alloys were produced in a vacuum-arc melting furnace. Heat treatment in the form of solution treatment was performed in a muffle furnace at a temperature of 1100 °C, with 1-h holding time and the samples were rapidly quenched in ice-brine. X-ray diffractometer (XRD) was used to analyses the phases present in each alloy whereas the optical microscope (OM) was employed to track the microstructural evolution and percentage porosity. The mechanical properties of the alloys were evaluated using a tensile test and compression test method while the micro-Vickers hardness measurements were conducted to evaluate hardness of the alloys. The XRD patterns of as-cast showed peaks belonging to the β and α″ phases and intermetallic B2 TiFe phases. The as quenched XRD peaks illustrated β phase only and Fe·Ti·O2 phases. The as-cast OM micrographs revealed equiaxed β grains, substructures, dendritic structure, and pores forming around the grain boundaries. The quenched OM showed only β equiaxed grains with pores throughout the grain boundaries. The tensile properties such as ultimate tensile strength (UTS) and elastic modulus (E) of as-cast TMF0 were 264 MPa and 79 GPa respectively and these properties changed upon quenching to 411 MPa and 66 GPa respectively. The elastic modulus of TMF1 in as-cast condition was 74 GPa. The UTS and E of TMF1, TMF2, and TMF3 in as-cast and quenched conditions were not recorded due to the fragility of the samples that failed prior to yielding any useful data. The compressive strength in as-cast and in quenched condition decreased with an increase in Fe content. The micro-Vickers hardness in as-cast and quenched conditions showed a similar trend with hardness increasing slightly upon quenching for TMF0, TMF1, and TMF3 alloys but slightly decreased in the case of TMF2. The fracture surfaces of all the as-cast and quenched alloys were comprised of ductile and brittle fracture.

Efficient adsorption of NO onto K, Na-embedded porous carbon material prepared by using zinc-bearing dust as activator

The increasingly generation of NO-containing flue gases and zinc-bearing dusts has posed huge pressure to the environment. A green process of integration of reduction of zinc-bearing dusts and preparation of porous carbon material with high NO adsorption capacity was developed and its mechanism was clarified in this paper. The reduced dusts with high content of iron (70.52 %) and low contents of harmful elements (0.017 % Zn, 0.015 % K and 0.026 % Na) could be used as high-quality raw material for ironmaking while the K, Na-embedded porous carbon material (APC) with surface area of 390.38 m2/g can be used as effective adsorbent for NO pollution control. The adsorption property and mechanism of NO on APC was investigated. It was found that the maximal removal rate of NO could reach 96.15 %, and the K, Na on porous carbon material could promote the chemisorption process of NO and increase the NO adsorption efficiency of APC. The hazardous waste was successfully utilized to treat the flue gas in this work.

Selective removal of chromium from laterite residue with high content of iron by the co-operation of phosphoric acid and oxalic acid

With the rising demand for nickel and cobalt, laterite residue containing chromium is extensively generated through the laterite hydrometallurgical process, posing a significant burden on environmental protection and the sustainable development of the nickel industry. This study presents a novel and environmentally friendly method for selectively extracting chromium from laterite residue and yielding iron phosphate concentrate. In this method, iron, as the major component, is simultaneously transformed into iron phosphate as solid state, while chromium is extracted into solution by a minimal amount of phosphoric acid. The effects of phosphoric acid and oxalic acid usage, temperature, liquid-to-solid ratio, and leaching time on the transformation and removal were investigated. Thermodynamic analysis and experimental results indicated that the addition of oxalic acid promoted chromium extraction with minimal impact on the transformation of hematite and iron phosphate. The results of SEM, XPS, and XRD revealed the conversion of laterite residue to iron phosphate. At an oxalic acid dosage of 10 %, almost 90 % of the iron remained in the residue as iron phosphate, while over 60 % of the chromium was extracted into the solution, resulting in a chromium concentration of 1.1 g/L. The solution underwent a two-step treatment process, primarily to recycle the soluble iron species. The extracted chromium was captured by adding calcium hydroxide at pH ∼ 3.0 in the form of phosphate.

On the influence of iron and silicon content on the phase composition of the Al-Fe-Si system

Increasing interest in intermetallic phases of the Al-Fe-Si system is associated with their high specific strength, corrosion and wear resistance, as well as the low cost of their production. To exhibit the most successful combination of properties, it is necessary to impart a specific compact morphology to the precipitated intermetallic phases. It is important to create an alloy with a composition capable of accepting plastic deformation. The purpose of the work is to develop the composition of an Al-Fe-Si system alloy capable of withstanding plastic deformation and determining the corresponding deformation interval. Based on computer modeling, an alloy composition capable of accepting plastic deformation was developed and the corresponding deformation interval was determined. The simulation was carried out in the ThermoCalc software package, TCAL8 database. It has been revealed that alloys with a high content of both silicon and iron are not characterized by the formation of a single-phase region, however, with a certain combination of alloy components, it is possible to achieve a quasi-single-phase structure, when the content of one phase is observed to be more than 90%. The solidus temperatures for different alloy compositions and the boundary conditions for the existence of phases have been determined. The α phase is present in the system from a temperature of 770°C up to a temperature of 446°C. In composition, it is found in the range from 5 to 35% iron with an amount of silicon of 10% and from 0 to 15% silicon with an iron content of 30%. The maximum amount of α phase was obtained for the Al60-65 alloy; Fe30-32; and Si5-10%, deformation temperature range is 600-450°C. Deformation in this region will ensure processing in a quasi-single-phase region without melting.

Baddeleyite U-Pb age and whole-rock geochemical characteristics of ∼ 1670 Ma diabase dyke in the Shennongjia area: Implications for the tectonic setting of northern Yangtze Craton during the late Paleoproterozoic

The Shennongjia Group in the northern margin of the Yangtze Craton consists mainly of thick carbonate rocks interlayered with some intervals of volcanic and terrigenous clastic rocks. With the geochronological achievements in recent years, the depositional age of this group can be constrained into the time span of 1400–1000 Ma at present, belonging to the Mesoproterozoic Ectasian period. It is also a potential candidate interval for the “Undefined System/Period” in the Regional Chronostratigraphic Chart of China. According to the 1:200,000-scale conventional regional geological survey in the ‘1960–1970 s’, at the northwest side of the dominant peak of the Mt. Shennongding, it shows a ring-shaped gabbro-diabase dyke intruded in these Ectasian formations. However, due to the lack of comprehensive studies, there are lots of controversy both about the intrusion time and the tectonic setting of the mafic dyke.In this study, by means of the LA-ICP-MS and SHRIMP method successfully, the baddeleyite from the Banbiyan gabbro-diabase dyke yielded gained the weighted average 207Pb/206Pb age 1668.3 ± 5 Ma (MSWD = 1, N = 53) and 1667.8 ± 7 Ma (MSWD = 0.7, N = 23), respectively. It represents an unambiguous late Paleoproterozoic Statherian Period magmatic event in northern Yangtze Craton. Further, for the first time, it indicates the existence of the geological records prior to ∼ 1.67 Ga in the Shennongjia area.In addition, Banbiyan gabbro-diabase samples have relatively concentrated SiO2 (48.33 % to 49.65 %) and high whole iron content (10.25 % to 12.78 %). They show Na2O + K2O ranging from 2.9 % to 4.64 % and TiO2 from 1.36 % to 1.62 %. All samples are enriched in LILE, e.g., Rb, K, and Ba. The REE pattern shows a moderately right-inclined curve between E-MORB and OIB. These geochemiacal characteristics are agreed with contemporaneous magmatic event in the southwestern Yangtze Craton, indicating a within-plate rifting background and should correspond to the rifting of the Columbia Supercontinent.

A New Type of Hydraulic Clutch with Magnetorheological Fluid: Theory and Experiment.

This paper presents a new type of hydraulic clutch operating by means of magnetorheological (MR) fluids and the results achieved from both theoretical analysis and experimental measurement. A hydraulic clutch system with MR working fluid and a rotating magnetic field located was designed. The clutch was based on the principle of using a rotating magnetic field created by an alternating current electromagnet to set the MR fluid in motion. To test the hydraulic clutch with a rotating magnetic field, MR fluids were produced by our laboratory, consisting of solid iron particles of various diameters mixed with a silicone oil. With MR working fluid and a rotating magnetic core was designed. The rheological properties of the MR fluids were assessed on the basis of tests carried out with a Brookfield DV2T rheometer equipped with a magnetic device for generating a magnetic field. The characteristics of the hydraulic clutch were tested on a specially built test stand. It was found that the torque transmitted by the clutch increased with the rotational speed of the magnetic field and with a lower rotational speed of the beaker in which the working fluid was placed. It was also found that the greatest torque occurred with the working fluid with the highest iron content. Based on the analysis of the structure and characteristics of the clutch in which the magnetic field is used, it has been shown that the design of the developed clutch is similar to that of an induction clutch, and its characteristics correspond to the characteristics of the eddy current clutch. Therefore, the proposed new clutch with MR fluid and rotating magnetic field can be applied to stationary power transmission systems in a manner similar to an eddy current clutch.

Slow drawdown, fast recovery: Stream macroinvertebrate communities improve quickly after large dam decommissioning

Abstract Dam removal is increasingly considered as a river restoration tool for impoundments that harm the environment or have exceeded their lifespan. However, few studies report the ecological consequences of large dam removal. We performed a multiple before‐after/control‐impact (mBACI) study to investigate the consequences of the decommissioning of a large dam (42 m high) on instream habitat and invertebrate communities in a temperate, forested catchment of northern Spain. Before decommissioning, lack of fine sediments and high concentrations of manganese and iron occurred below the dam but decreased downstream. Invertebrate taxa richness and diversity were reduced, and pollution‐sensitive taxa were missing just below the dam. The drawdown of the reservoir, the first step towards its decommissioning, mobilized stored sediments causing frequent turbidity peaks downstream, which nevertheless, caused no detrimental effects on macroinvertebrate communities. One year after drawdown, the communities downstream from the dam, as well as those in the newly formed stream in the area formerly impounded by the reservoir, became very similar to those in control reaches, showing a successful restoration project. Synthesis and applications. Dam decommissioning helps restore instream habitats and facilitates the recovery of invertebrate communities in a very short time frame if there are nearby sources of potential colonizers. Slow drawdown reduces the transport of the sediments accumulated in the reservoir and their potential downstream impacts, even more if prior to drawdown the reservoir is kept full for years to promote the deposition of sediments in marginal areas that will later be readily colonized by trees.

Feammox bacterial biofilm formation in HFMB

Nitrogen pollution has been increasing with the development of industrialization. Consequently, the excessive deposition of reactive nitrogen in the environment has generated the loss of biodiversity and eutrophication of different ecosystems. In 2005, a Feammox process was discovered that anaerobically metabolizes ammonium. Feammox with the use of hollow fiber membrane bioreactors (HFMB), based on the formation of biofilms of bacterial communities, has emerged as a possible efficient and sustainable method for ammonium removal in environments with high iron concentrations. This work sought to study the possibility of implementing, at laboratory scale, an efficient method by evaluating the use of HFMB. Samples from an internal circulation reactor (IC) incubated in culture media for Feammox bacteria. The cultures were enriched in a batch reactor to evaluate growth conditions. Next, HFMB assembly was performed, and Feammox parameters were monitored. Also, conventional PCR and scanning electron microscopy (SEM) analysis were performed to characterize the bacterial communities associated with biofilm formation. The use of sodium acetate presented the best performance for Feammox activity. The HFMB operation showed an ammonium (NH4+) removal of 50%. SEM analysis of the fibers illustrated the formation of biofilm networks formed by bacteria, which were identified as Albidiferax ferrireducens, Geobacter spp, Ferrovum myxofaciens, Shewanella spp., and Anammox. Functional genes Archaea/Bacteria ammonia monooxygenase, nrxA, hzsB, nirS and nosZ were also identified. The implementation of HFMB Feammox could be used as a sustainable tool for the removal of ammonium from wastewater produced because of anthropogenic activities.

Investigation of the accuracy of a portable 109Cd XRF system for the measurement of iron in skin

We have previously reported the design of a portable 109Cd x-ray fluorescence (XRF) system to measure iron levels in the skin of patients with either iron overload disease, such as thalassemia, or iron deficiency disease, such as anemia. In phantom studies, the system was found to have a detection limit of 1.35 μg Fe per g of tissue for a dose of 1.1 mSv. However, the system must provide accurate as well as precise measurements of iron levels in the skin in order to be suitable for human studies. The accuracy of the system has been explored using several methods. First, the iron concentrations of ten pigskin samples were assessed using both the portable XRF system and ICP-MS, and the results were compared. Overall, it was found that XRF and ICP-MS reported average values for iron in skin that were comparable to within uncertainties. The mean difference between the two methodologies was not significant, 2.5 ± 4.6 μg Fe per g. On this basis, the system could be considered accurate. However, ICP-MS measurements reported a wider range of values than XRF, with two individual samples having ICP-MS results that were significantly elevated (p < 0.05) compared to XRF. Synchrotron μXRF maps of iron levels in pigskin were acquired on the BioXAS beam line of the Canadian Light Source. The μXRF maps indicated two important features in the distribution of iron in pigskin. First, there were small areas of high iron concentration in the pigskin samples, that were predominantly located in the dermis and hypodermis at depths greater than 0.5 mm. Monte Carlo modelling using the EGS 5 code determined that if these iron ‘hot spots’ were located towards the back of the skin at depths greater than 0.5 mm, they would not be observed by XRF, but would be measured by ICP-MS. These results support a hypothesis that iron levels in the two samples that reported significantly elevated ICP-MS results compared to XRF may have had small blood vessels at the back of the skin. Second, the synchrotron μXRF maps also showed a narrow (approximately 100μm thick) layer of elevated iron at the surface of the skin. Monte Carlo models determined that, as expected, the XRF system was most sensitive to these skin layers. However, the simulations found that the XRF system, when calibrated against homogenous water-based phantoms, was found to accurately measure average iron levels in the skin of normal pigs despite the greater sensitivity to the surface layer. The Monte Carlo results further indicated that with highly elevated skin surface iron levels, the XRF system would not provide a good estimate of average skin iron levels. The XRF estimate could, with correction factors, provide a good estimate of the iron levels in the surface layers of skin. There is limited data on iron distribution in skin, especially under conditions of disease. If iron levels are elevated at the skin surface by diseases including thalassemia and hemochromatosis, this XRF device may prove to be an accurate clinical tool. However, further data are required on skin iron distributions in healthy and iron overload disease before this system can be verified to provide accurate measurements.

Trace Elements in Alzheimer's Disease and Dementia: The Current State of Knowledge.

Changes in trace element concentrations are being wildly considered when it comes to neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease. This study aims to present the role that trace elements play in the central nervous system. Moreover, we reviewed the mechanisms involved in their neurotoxicity. Low zinc concentrations, as well as high levels of copper, manganese, and iron, activate the signalling pathways of the inflammatory, oxidative and nitrosative stress response. Neurodegeneration occurs due to the association between metals and proteins, which is then followed by aggregate formation, mitochondrial disorder, and, ultimately, cell death. In Alzheimer's disease, low Zn levels suppress the neurotoxicity induced by β-amyloid through the selective precipitation of aggregation intermediates. High concentrations of copper, iron and manganese cause the aggregation of intracellular α-synuclein, which results in synaptic dysfunction and axonal transport disruption. Parkinson's disease is caused by the accumulation of Fe in the midbrain dopaminergic nucleus, and the pathogenesis of multiple sclerosis derives from Zn deficiency, leading to an imbalance between T cell functions. Aluminium disturbs the homeostasis of other metals through a rise in the production of oxygen reactive forms, which then leads to cellular death. Selenium, in association with iron, plays a distinct role in the process of ferroptosis. Outlining the influence that metals have on oxidoreduction processes is crucial to recognising the pathophysiology of neurodegenerative diseases and may provide possible new methods for both their avoidance and therapy.

Humic acid enhances phosphorus transport in soil and uptake by maize

AbstractBackgroundMost of the phosphorus (P) applied to low fertility, acidic tropical soils with high iron and aluminum oxide contents end up adsorbed to soil colloids and not available to crops. Diffusion of P from fertilizers was found to be facilitated by coating with humic substances and by soil moisture.AimHowever, there is still controversy on the effect of humic substances on soil P forms and diffusion, and there is a gap in the knowledge of how coating the fertilizer interacts with soil water.MethodsWe studied P diffusion and availability from a conventional single superphosphate and a humic acid‐coated superphosphate in Petry dishes as affected by soil moisture and the effect of the distance of the fertilizer to the roots using a root‐matt methodology.ResultsCoating single superphosphate with humic substances from leonardite (0.5%) and increasing water moisture resulted in improved P diffusion in the soil and plant P uptake. Maize dry matter increased by humic acid‐coated phosphate from 3% to 26%, depending on the distance from the fertilizer to the roots. Therefore, there is evidence of a lower P adsorption to soil colloids. The coated fertilizer increased labile P by 76% around the fertilizer granule, while higher levels of less labile P were observed with the use of conventional single superphosphate.ConclusionAll this resulted in facilitated P transport from the soil to the roots, which is important mainly in double‐cropped systems where the second crop is usually exposed to temporary drought.

Iron silicate perovskite and postperovskite in the deep lower mantle

Ferromagnesian silicates are the dominant constituents of the Earth's mantle, which comprise more than 80% of our planet by volume. To interpret the low shear-velocity anomalies in the lower mantle, we need to construct a reliable transformation diagram of ferromagnesian silicates over a wide pressure-temperature (P-T) range. While MgSiO3 in the perovskite structure has been extensively studied due to its dominance on Earth, phase transformations of iron silicates under the lower mantle conditions remain unresolved. In this study, we have obtained an iron silicate phase in the perovskite (Pv) structure using synthetic fayalite (Fe2SiO4) as the starting material under P-T conditions of the lower mantle. Chemical analyses revealed an unexpectedly high Fe/Si ratio of 1.72(3) for the Pv phase in coexistence with metallic iron particles, indicating incorporation of about 25 mol% Fe2O3 in the Pv phase with an approximate chemical formula (Fe2+0.75Fe3+0.25)(Fe3+0.25Si0.75)O3. We further obtained an iron silicate phase in the postperovskite (PPv) structure above 95 GPa. The calculated curves of compressional (VP) and shear velocity (VS) of iron silicate Pv and PPv as a function of pressure are nearly parallel to those of MgSiO3, respectively. To the best of our knowledge, the iron silicate Pv and PPv are the densest phases among all the reported silicates stable at P-T conditions of the lower mantle. The high ferric iron content in the silicate phase and the spin-crossover of ferric iron at the Si-site above ~55 GPa should be taken into account in order to interpret the seismic observations. Our results would provide crucial information for constraining the geophysical and geochemical models of the lower mantle.