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Previous studies have detected abnormal serum ferritin levels in patients with depression; however, the results have been inconsistent. This study used quantitative susceptibility mapping (QSM) for the first time to examine brain iron concentration in depressed patients and evaluated whether it is related to severity. We included three groups of age- and gender-matched participants: 30 patients with mild-moderate depression (MD), 14 patients with major depression disorder (MDD) and 20 control subjects. All participants underwent MR scans with a 3D gradient-echo sequence reconstructing for QSM and performed the 17-item Hamilton Depression Rating Scale (HDRS) test. In MDD, the susceptibility value in the bilateral putamen was significantly increased compared with MD or control subjects. In addition, a significant difference was also observed in the left thalamus in MDD patients compared with controls. However, the susceptibility values did not differ between MD patients and controls. The susceptibility values positively correlated with the severity of depression as indicated by the HDRS scores. Our results provide evidence that brain iron deposition may be associated with depression and may even be a biomarker for investigating the pathophysiological mechanism of depression. [ABSTRACT FROM AUTHOR]

It is important to develop an accurate assessment of fundamental data of lanthanides in high temperature molten salts to enable an efficient application of pyroprocessing. This requires a careful consideration of uncertainties in the reported results. In this study, cyclic voltammetry (CV) tests of LaCl3 in KCl-LiCl molten salt were conducted at low concentration levels in the molten salt at 723 K and at several scan rates. The CV signals were subsequently analyzed through the conventional CV analysis and using a BET-based model through a nonlinear least-squares fitting procedure. It was determined that the parameters of the model were strongly correlated and the support plane procedure was implemented to assign joint confidence intervals for the diffusivity of lanthanum. Accounting for the correlations led to a significant increase in the uncertainty of the reported diffusivity which led to better agreement with the literature. Accounting for the correlations may be important for higher concentration levels. [ABSTRACT FROM AUTHOR]

Features of the wear of mating parts of ball valves made of heat-resistant cast alloy ZhS-6U and cermet based on uncoated titanium carbide TiC-ZhS6U and with wear-resistant TiN and Zr-Ti-N-C coatings are studied. It is established that wear-resistant coatings based on cermets prevent the emergence of hard TiC inclusions at the friction surface thereby reducing friction pair component abrasive and mechanical wear and decreasing the overall degree of ball valve wear. [ABSTRACT FROM AUTHOR]

The use of efficient methods for data processing has always been of interest by researchers in the field of earth science. Pattern recognition techniques are appropriate methods for high-dimensional data such as geochemical data. Evaluation of geochemical distribution of REEs needs to use such methods. Especially multivariate nature of REEs data makes it a good target for numerical analysis. The main subject of this paper is application of unsupervised pattern recognition approaches in evaluating geochemical distribution of rare earth elements (REEs) in the Kiruna type magnetite-apatite deposit of Se-Chahun. For this purpose, 42 bulk lithology samples were collected from Se-Chahun iron ore deposit. In this study, 14 rare earth elements were measured with ICP-MS. Pattern recognition makes it possible to evaluate the relations between the samples based on all these 14 features, simultaneously. In addition to providing easy solutions, discovery of the hidden information and relations of data samples is the advantage of these methods. Therefore, four clustering methods (unsupervised pattern recognition) including modified basic sequential algorithmic scheme (MBSAS), hierarchical (agglomerative), k-means and self-organizing map (SOM) were applied and results were evaluated using silhouette criterion. Samples were clustered in four types. Finally, the results of this study were validated with geological facts, and analysis results such as SEM, XRD, ICP-MS and optical mineralogy. The results of k-means and SOM have the best matches with reality, experimental studies of samples and also field surveys. Since only the rare earth elements are used in this division, a good agreement of the results with lithology is considerable. It concluded that the combination of the proposed methods and geological studies, leads to finding some hidden information and this approach has the best results compared to using only one of them. [ABSTRACT FROM AUTHOR]

Composite molecular sieve Y/SBA-15(C-Y) was prepared by microwave method, while Ce was loaded by ion exchange method to the composite molecular sieves (Ce-Y/SBA-15 (C-X)). Productive-type middle distillate hydrocracking catalyst was prepared from C-X and C-Y loaded. FI-IR, XPS, Pyridine IR, and TG-DTG had been used to characterize the C-X's and C-Y's structure and acidity. The results showed that Ce loaded not only had not broken the original structure of C-Y, but also improved silica alumina ratio of C-X, furthermore improved its total acid content. Through polarization and entrainment, Ce increased the skeleton and hydroxyl silicon aluminum hydroxy on electronic probability of migration to the cage, thus enhance the C-X's B acid strength, make it more suitable for heavy oil processing. As compared with C-Y, the selectivity and yield of middle distillates over C-X was 0.7 % and 1.8 % higher, respectively. C-X have the greatest relief wax oil viscosity index, best once cracking selectivity, and lowest levels of diesel oil solidifying point in the three catalysts. [ABSTRACT FROM AUTHOR]

The knowledge of redox equilibria of iron in multicomponent molten slags is of significant importance to understand the viscosity, electrical conductivity and structure of iron-containing slags. However, the available data of molar ratio of ferric ion to ferrous ion are limited due to the difficulty of experiment and heavy workload. In this study, a model was established to estimate the (normally, most of ferric ions exist in the form of complex anions such as ) ratio in CaO-MgO-Al2O3-SiO2-'FeO t' slags, which can give good estimation results compared to the experimental measured values. From the model, by increasing oxygen partial pressure or decreasing temperature, the ratio will increase. Different components have different influences on ratio: CaO and MgO are beneficial for the increase of this ratio, but Al2O3 and SiO2 have reverse effects. [ABSTRACT FROM AUTHOR]

The presence of pesticides, herbicides and fertilisers negatively affect aquatic communities in general, and particularly amphibians in their larval phase, even though sensitivity to pollutants is highly variable among species. The Llobregat Delta (Barcelona, Spain) has experienced a decline of amphibian populations, possibly related to the reduction in water quality due to the high levels of farming activity, but also to habitat loss and alteration. We studied the effects of increasing ammonium nitrate and sodium nitrate levels on the survival and growth rate of Alytes obstetricans tadpoles under experimental conditions. We exposed larvae to increasing concentrations of nitrate and ammonium for 14 days and then exposed them to water without pollutants for a further 14 days. Only the higher concentrations of ammonium (>33.75 mg/L) caused larval mortality. The growth rate of larvae was reduced at ≥22.5 mg/L NH , although individuals recovered and even increased their growth rate once exposure to the pollutant ended. The effect of nitrate on growth rate was detected at ≥80 mg/L concentrations, and the growth rate reduction in tadpoles was even observed during the post-exposure phase. The concentrations of ammonium with adverse effects on larvae are within the range levels found in the study area, while the nitrate concentrations with some adverse effect are close to the upper range limit of current concentrations in the study area. Therefore, only the presence of ammonium in the study area is likely to be considered of concern for the population of this species, even though the presence of nitrate could cause some sublethal effects. These negative effects could have an impact on population dynamics, which in this species is highly sensitive to larval mortality due to its small clutch size and prolonged larval period compared to other anuran amphibians. [ABSTRACT FROM AUTHOR]

The extraction of Ti(IV) from nitric acid has been carried out using some organophosphorus extractants in kerosene. The Ti(IV) extraction in the investigated systems is endothermic. Oxalic acid was effective for stripping Ti(IV). The maximum loading of Ti(IV) was found to be 6.13 × 10−3, 6.175 × 10−3and 5.005 × 10−3M of Ti(IV) per mole extractant for CYANEX 925, 923 and 921, respectively, after five extraction stages. Kerosene is a more effective diluent for extraction of Ti(IV). FT-IR characterization and the separation of Ti(IV) are also discussed. [ABSTRACT FROM PUBLISHER]

Sodium salts were used in the reduction roasting and magnetic separation process to separate and recover iron and manganese from the high-iron manganese oxide ores to utilize the complex ores. Results showed that Na2S2O3was the most effective salt. A magnetic concentrate with 86.39 wt% TFe and 96.21 wt% Fe recovery as well as a nonmagnetic product with 54.84 wt% TMn and 85.96 wt% Mn recovery was obtained when the ore sample was reduced at 1100°C for 100 min in the presence of 7 wt% Na2S2O3. In addition, the effects of roasting and separation parameters on the recovery of manganese and iron and the function mechanism of Na2S2O3were investigated. [ABSTRACT FROM PUBLISHER]

Nowadays green synthesis of metal nanoparticles is a developing area of research. In this study, titanium dioxide nanoparticles were biosynthesized using an aqueous solution of Echinacea purpurea herba extract as a bioreductant. This is novel and interesting method for synthesis of TiO2 nanoparticles. The prepared titanium dioxide nanoparticles were characterized using ultraviolet-visible spectroscopy (UV-VIS), transmission electron microscopy (SEM), total reflection X-Ray fluorescence analysis (TXRF) and Fourier-transform infrared spectroscopy (FTIR). The size of TiO2 nanoparticles was found to be in the range of 120 nm. Moreover, the alkaline reaction of the solution (pH = 8) resulted in the increase in absorbance (280 nm), which facilitates the growth of the number of TiO2 nanoparticles in the studied solution. Also, synthesis of TiO2 nanoparticles using green resources like Echinacea purpurea herba is a better alternative to chemical synthesis, since this green synthesis is pollutant-free and eco-friendly. [ABSTRACT FROM AUTHOR]

Calsequestrin, the only known protein with cyclical storage and supply of calcium as main role, is proposed to have other functions, which remain unproven. Voluntary movement and the heart beat require this calcium flow to be massive and fast. How does calsequestrin do it? To bind large amounts of calcium in vitro, calsequestrin must polymerize and then depolymerize to release it. Does this rule apply inside the sarcoplasmic reticulum (SR) of a working cell? We answered using fluorescently tagged calsequestrin expressed in muscles of mice. By FRAP and imaging we monitored mobility of calsequestrin as [Ca2+] in the SR-measured with a calsequestrin-fused biosensor-was lowered. We found that calsequestrin is polymerized within the SR at rest and that it depolymerized as [Ca2+] went down: fully when calcium depletion was maximal (a condition achieved with an SR calcium channel opening drug) and partially when depletion was limited (a condition imposed by fatiguing stimulation, long-lasting depolarization, or low drug concentrations). With fluorescence and electron microscopic imaging we demonstrated massive movements of calsequestrin accompanied by drastic morphological SR changes in fully depleted cells. When cells were partially depleted no remodeling was found. The present results support the proposed role of calsequestrin in termination of calcium release by conformationally inducing closure of SR channels. A channel closing switch operated by calsequestrin depolymerization will limit depletion, thereby preventing full disassembly of the polymeric calsequestrin network and catastrophic structural changes in the SR. [ABSTRACT FROM AUTHOR]

Conical aluminium projectiles of apex angle 34 degrees were made to impact thin aluminium targets inclined at an angle of 60 degrees at low subordnance velocities where material strength effects are still valid. Thin targets of thickness 1.5 mm and 2 mm underwent failure by reverse petalling as the projectiles penetrated the targets. Projectiles underwent ricochet while impacting 2.5 mm targets causing severe dents and visible contact marks on the target. While the projectile nose tips were separated in the 1.5 mm and 2 mm cases, the projectiles impacting 2.5 mm targets underwent substantial nose deformation. Numerical simulation performed using ABAQUS/Explicit was able to capture the projectile deformation and target deformation quite well phenomenologically. [ABSTRACT FROM AUTHOR]

A J integer and CTOD test are usually done on materials undergoes plastic deformation prior to failure. The testing material more or less resembles the original one, although dimensions can be reduced proportionally. More than 3 tests are done to minimize any experimental deviations. The specimen is placed on the work table and a notch is created exactly at the centre. The crack should be generated such that the defect length is about half the depth. The load applied on the specimen is generally a three point bending load. A strain gauge is used to measure the crack opening. Crack tip plastically deforms until a critical point after which a crack is initiated that may lead to either partial or complete failure. [ABSTRACT FROM AUTHOR]

Response of a material under dynamic loading is different as compared to static loading. Dynamic material properties are therefore necessary for assessment of structural integrity and safety. Gas turbine aero engine frontal components like fan and compressors are critical and prone for foreign object impact as these components are exposed directly to the environment. Design of aircraft engine components like fan and compressor are critical and it is mandatory to design such components to withstand high impact loads. In view of this high strain rate test of Ti-6Al-4 V alloy has been carried out in strain rate range of 1000 s -1 to 4000 s -1 using Split Hopkinson Bar (SHB). Force equilibrium analysis for each test is carried out to confirm the validity of the test results. Quasi-static test was also carried out for comparison with high strain rate test. From the tests, flow behavior of Ti-6Al-4 V alloy at high strain rate is obtained. It is observed that the material have positive strain rate sensitivity and it fails by fracture under high strain rate compressive loading. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osseointegration of implant materials with surrounding tissues is crucial for their long-term success. OBJECTIVE: The aim of the present study was to investigate the extent of physisorption of polymers on a titanium alloy (Ti6Al4V) surface. In addition, the water contact angles on the physisorbed coatings were measured to compare the hydrophilicity of the modified surfaces. METHODS: Ti6Al4V disks (13-mm diameter) were prepared to evaluate polymer adsorption on the alloy surface. The surface hydrophilicity was evaluated by contact angle (θ) measurement. Physisorption of polymers on the surface was evaluated quantitatively by a colorimetric method. RESULTS: The largest contact angles were recorded on samples polished with silicon carbide papers of 1200 and 500 grit (Poli1200 and Poli500 samples: 97.3 ± 4.8 and 84.8 ± 11.0, respectively). Treatment of polished samples with Kroll solution remarkable reduced the contact angles to 46.8 ± 11.6 and 58.6 ± 11.5 for Poli500+Kroll and Poli1200+Kroll, respectively. Contact angles were further reduced in response to PolyNaSS and PAA treatment. Regardless of surface treatment, there was no significant difference in the contact angles on surfaces after SiC 500 and 1200 grit polishing. CONCLUSIONS: Physisorbed polymer coatings (such as PAA) on the Ti6Al4V surface can reduce the contact angle and improve the hydrophilicity and wettability of the alloy surface. Moreover, physisorption is a simple technique that does not require any special equipment. [ABSTRACT FROM AUTHOR]

Four new titanium catecholate complexes - [Ti2(Cat)2(CatH)2(OCH3)2(CH3OH)2] ( 1; Cat = C6H4O22-), [Ti2(4 tBuCat)4(CH3OH)2] ·2CH3OH ( 2·2CH3OH; 4 tBuCat = [4- t-C4H9-C6H3O2]2-), [Ti(Cat)2(dmf)2] ( 3; dmf = N, N-dimethylformamide), and [Na(dme)Ti(Cat)3]2[Na(dme)CH3OH]2 ( 4; dme = 1,2-dimethoxyethane) - have been obtained by treatment of Ti(OCH3)4 with catechols in methanol and structurally characterized. Complex 3 is the first example of a neutral mononuclear titanium catecholate containing more than one catechol molecule per titanium atom. Complexes 1 and 2 are neutral dimers in the solid state, each with a catechol/Ti ratio equal to 2 and featuring one of the catechol ligands bridging two titanium centres in a singly bridging chelate µ2-(O,O′,O′) mode. The other catechol molecule is either a terminal bidentate chelating ligand (complex 2) or a Ti monodentate ligand (complex 1). Complex 4 is a heterometallic aryloxide complex with a tetrameric [{Na(dme)Ti(Cat)3)2]2- (Ti2Na2) core as an anionic moiety and Na ions, solvated by methanol and dme ligands - [{Na(dme)(CH3OH)}2]2+ - as a cationic counterpart. Each Ti centre in 4 is octahedrally coordinated by three catechol ligands, demonstrating three distinct types of bridging modality. It was shown that 1- 4 effectively catalyze the selective homogeneous hydrogenation of acetylene to ethylene. Various kinetic relationships were determined and analyzed, enabling a reaction pathway for this catalytic reaction to be proposed. [ABSTRACT FROM AUTHOR]

The adsorption behavior of rice husk ash with respect to manganese and iron has been studied by batch methods to consider its application for water and waste water treatment. The optimum conditions of adsorption were determined by investigating the effect of initial metal ion concentration, contact time, adsorbent dose, pH value of aqueous solution and temperature. Adsorption equilibrium time was observed at 120 min. The adsorption efficiencies were found to be pH dependent. The equilibrium adsorption experimental data were found to fit the Langmuir, Freundlich and Temkin isotherms for iron, but fitted only Langmuir isotherm for manganese. The pseudo-second order kinetic model was found to describe the manganese and iron kinetics more effectively. The thermodynamic experiment revealed that the adsorption processes involving both metals were exothermic. The adsorbent was finally applied to typical raw water with initial manganese and iron concentrations of 3.38 mg/l for Fe and 6.28 mg/l, respectively, and the removal efficiency was 100 % for Mn and 70 % for Fe. The metal ions were desorbed from the adsorbent using 0.01 M HCl, it was found to quantitatively remove 67 and 86 % of Mn and Fe, respectively, within 2 h. The results revealed that manganese and iron are considerably adsorbed on the adsorbent and could be an economic method for the removal of these metals from aqueous solutions. [ABSTRACT FROM AUTHOR]

A method is proposed for preparing high-strength cast iron with spheroidal graphite by introducing calcium oxide and other calcium-containing ingredients into the composition of flux cored wire. It is shown that introduction of carbon, silicon, and calcium facilitates the formation in a surfacing layer of a ferrite-pearlite structure and spheroidal graphite. Theoretical bases are provided for the surfacing metal composition. [ABSTRACT FROM AUTHOR]

PURPOSE. The purpose of this study was to evaluate the resistance to deformation under static overloading by measuring yield and fracture strength, and to analyze the failure characteristics of implant assemblies made of different titanium grades and connections. MATERIALS AND METHODS. Six groups of implant assemblies were fabricated according to ISO 14801 (n=10). These consisted of the combinations of 3 platform connections (external, internal, and morse tapered) and 2 materials (titanium grade 2 and titanium grade 4). Yield strength and fracture strength were evaluated with a computer-controlled Universal Testing Machine, and failed implant assemblies were classified and analyzed by optical microscopy. The data were analyzed using the One-way analysis of variance (ANOVA) and Student's t-test with the level of significance at P=.05. RESULTS. The group IT4S had the significantly highest values and group IT2 the lowest, for both yield strength and fracture strength. Groups IT4N and ET4 had similar yield and fracture strengths despite having different connection designs. Group MT2 and group IT2 had significant differences in yield and fracture strength although they were made by the same material as titanium grade 2. The implant system of the similar fixture-abutment interfaces and the same materials showed the similar characteristics of deformation. CONCLUSION. A longer internal connection and titanium grade 4 of the implant system is advantageous for static overloading condition. However, it is not only the connection design that affects the stability. The strength of the titanium grade as material is also important since it affects the implant stability. When using the implant system made of titanium grade 2, a larger diameter fixture should be selected in order to provide enough strength to withstand overloading. [ABSTRACT FROM AUTHOR]

Since its first introduction in the 1950s, Ti6Al4V became the most favorable titanium alloy due to its attractive mechanical and physicochemical properties and is currently extensively used e.g. in biomedical industry. However, its poor tribological properties limit its use in orthopedic applications. Hence, a variety of attempts have been made in order to improve tribological performance of titanium alloys, especially focusing on surface modification. This paper represents an overview of surface modification techniques applied on Ti6Al4V alloy during the last 15 years. The effects of oxidizing, deposition of carbon-based amorphous coatings, nitrogen-based layers and other surface modification techniques have been reviewed. According to the provided information, the durability, efficiency and reliability of popular anti-wear coatings strongly depends not only on the type of surface modification, research methods or experiment setup, but also on the experiment conditions, such as sliding velocity or applied load. Due to that, it is recommended to develop unified standards for wear tests of biomedical alloys used in orthopedic-related applications, e.g. arthroplasty. [ABSTRACT FROM AUTHOR]

The formation of endohedral metallofullerenes (EMFs) in an electric arc is reported for the mixed-metal Sc-Ti system utilizing methane as a reactive gas. Comparison of these results with those from the Sc/CH4 and Ti/CH4 systems as well as syntheses without methane revealed a strong mutual influence of all key components on the product distribution. Whereas a methane atmosphere alone suppresses the formation of empty cage fullerenes, the Ti/CH4 system forms mainly empty cage fullerenes. In contrast, the main fullerene products in the Sc/CH4 system are Sc4C2@C80 (the most abundant EMF from this synthesis), Sc3C2@C80, isomers of Sc2C2@C82, and the family Sc2C2 n (2 n=74, 76, 82, 86, 90, etc.), as well as Sc3CH@C80. The Sc-Ti/CH4 system produces the mixed-metal Sc2TiC@C2 n (2 n=68, 78, 80) and Sc2TiC2@C2 n (2 n=80) clusterfullerene families. The molecular structures of the new, transition-metal-containing endohedral fullerenes, Sc2TiC@ Ih-C80, Sc2TiC@ D5 h-C80, and Sc2TiC2@ Ih-C80, were characterized by NMR spectroscopy. The structure of Sc2TiC@ Ih-C80 was also determined by single-crystal X-ray diffraction, which demonstrated the presence of a short Ti=C double bond. Both Sc2TiC- and Sc2TiC2-containing clusterfullerenes have Ti-localized LUMOs. Encapsulation of the redox-active Ti ion inside the fullerene cage enables analysis of the cluster-cage strain in the endohedral fullerenes through electrochemical measurements. [ABSTRACT FROM AUTHOR]

It was spectrophotometrically determined that dilute aqueous mixtures of methylene blue cationic dye with sodium alginate are stable self-assembling systems from dissolved state noncovalent complexes. The influence of the mixture components, the molecular weight of sodium alginate and composition of the environment on the binding ability of the polymer toward to dye were investigated. The critical pH values and also amounts of inorganic salts, an oppositely charged polyelectrolyte and an organic solvent, causing a complete inhibition of complex formation and the release of dye were determined. [ABSTRACT FROM AUTHOR]

The present research was conducted on thin-walled castings with 5 mm wall thicknesses. This study addresses the effect of the influence of different master alloys, namely: (1) Al-5%Ti-1%B, (2) Al-5%Ti and (3) Al-3%B, respectively on the structure and the degree of undercooling (ΔTα = Tα−Tmin, where Tα - the equilibrium solidification temperature, Tmin - the minimum temperature at the beginning of α(Al) solidification) of an Al-Cu alloy. The process of fading has been investigated at different times spent on the refinement treatment ie. from 3, 20, 45 and 90 minutes respectively, from the dissolution of master alloys. A thermal analysis was performed (using a type-S thermocouple) to determine cooling curves. The degree of undercooling and recalescence were determined from cooling and solidification curves, whereas macrostructure characteristics were conducted based on a metallographic examination. The fading effect of the refinement of the primary structure is accompanied by a significant change in the number (dimension) of primary grains, which is strongly correlated to solidification parameters, determined by thermal analysis. In addition to that, the analysis of grain refinement stability has been shown with relation to different grain refinements and initial titanium concentration in Al-Cu base alloy. Finally, it has been shown that the refinement process of the primary structure is unstable and requires strict metallurgical control. [ABSTRACT FROM AUTHOR]

A356 is one of the widely used aluminium casting alloy that has been used in both sand and die casting processes. Large amounts of scrap metal can be generated from the runner systems and feeders. In addition, chips are generated in the machined parts. The surface area with regard to weight of chips is so high that it makes these scraps difficult to melt. Although there are several techniques evolved to remedy this problem, yet the problem lies in the quality of the recycled raw material. Since recycling of these scrap is quite important due to the advantages like energy saving and cost reduction in the final product, in this work, the recycling efficiency and casting quality were investigated. Three types of charges were prepared for casting: %100 primary ingot, %100 scrap aluminium and fifty-fifty scrap aluminium and primary ingot mixture were used. Melt quality was determined by calculating bifilm index by using reduced pressure test. Tensile test samples were produced by casting both from sand and die moulds. Relationship between bifilm index and tensile strength were determined as an indication of correlation of melt quality. It was found that untreated chips decrease the casting quality significantly. Therefore, prior to charging the chips into the furnace for melting, a series of cleaning processes has to be used in order to achieve good quality products. [ABSTRACT FROM AUTHOR]

ABSTRACT The individual toxic effects of aluminum and acrylamide are known but there is no data on their combined effects. The present study investigates the toxic effects after combined exposure to these toxicants on: (i) oxidative stress during combined chronic exposure to aluminum and acrylamide on kidney function (ii) correlation of oxidative stress with metallothionein (MT) and inflammatory cytokines expression, DNA damage, and histopathological changes. Rats were exposed to aluminum (50 mg/kg body weight) in drinking water and acrylamide (20 mg/kg body weight) by gavage either individually or in combination for 3 weeks. Exposure rats to aluminum chloride or acrylamide alone and in combination induced nephrotoxicity, as evidenced by a decrease in the 24-h urine volume and uric acid levels in plasma and an increase of plasma creatinine, urea, and blood urea nitrogen levels. Nephrotoxicity was objectified by a significant increase in malondialdehyde level, advanced oxidation protein, and protein carbonyl contents, whereas reduced glutathione, nonprotein thiol, vitamin C levels, catalase, and glutathione peroxidase activities showed a significant decline. Superoxide dismutase activity and its gene expression were increased. Aluminum and acrylamide co-exposure exhibited synergism in various biochemical variables and also in DNA damage. Kidney total MT levels and genes expression of MT1, MT2, and proinflammatory cytokines were increased. All these changes were supported by histopathological observations. Co-exposure to aluminum and acrylamide exhibited synergism and more pronounced toxic effects compared with their individual effects based on various biochemical variables, genotoxic, and histopathological changes. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1044-1058, 2016. [ABSTRACT FROM AUTHOR]

The subcellular partitioning approach provides useful information on the location of metals within cells and is often used on organisms with high levels of bioaccumulation to establish relationships between the internal concentration and the potential toxicity of metals. Relatively little is known about the subcellular partitioning of metals in wild fish with low bioaccumulation levels in comparison with those from higher contaminated areas. This study aims to examine the subcellular partitioning of various metals considering their chemical affinity and essentiality at relatively low contamination levels. Class A (Y, Sr), class B (Cu, Cd, MeHg), and borderline (Fe, Mn) metal concentrations were measured in livers and subcellular fractions of yellow perch (n = 21) collected in Lake Saint-Pierre, QC, Canada. The results showed that all metals, apart from MeHg, were distributed among subcellular fractions according to their chemical affinity. More than 60% of Y, Sr, Fe, and Mn were found in the metal-sensitive fractions. Cd and Cu were largely associated with the metallothionein-like proteins and peptides (60% and 67% respectively) whereas MeHg was found mainly in the metal-sensitive fractions (86%). In addition, the difference between the subcellular distribution of Cu and other essential metals like Fe and Mn denotes that, although the essentiality of some metals is a determinant of their subcellular distribution, the chemical affinity of metals is also a key driver. The similarity of the subcellular partitioning results with previous studies on yellow perch and other fish species from higher contaminated areas supports the idea that metals are distributed in the cellular environment according to their chemical properties regardless of the bioaccumulation gradient. [Display omitted] • Yellow perch with low metal concentrations collected from Lake Saint-Pierre. • Subcellular partitioning (SP) of metals was assessed in yellow perch liver. • SP of Y, Sr, Fe, Mn, Cu and Cd is likely linked to their chemical class. • MeHg was found in the metal-sensitive fractions unlike other class B metals. • SP of B metals was similar to studies with higher contamination gradients. [ABSTRACT FROM AUTHOR]

There is debate in the literature on whether or not iron can be carburized by simply inserting an iron bar into a charcoal fire. Experiments are presented here in which wrought iron bars have been held in a cylindrical enclosure filled with burning charcoal produced by air flowing up from tuyeres at the bottom with the bottom end of the bars held in the 900°C-1050°C range for 30 min. The bars carburized to a remarkable extent. Martensite case depths on a water-quenched bar were measured ranging from 0.75 mm at the hot bottom end and dropping to 0.02 mm at a distance of 295 mm (11.6 inches) up the bar. The surface of the bar was file hard over this length with measured surface hardnesses in the 60-65 Rc range. [ABSTRACT FROM AUTHOR]

Rats overfed during lactation show higher visceral adipose tissue (VAT) mass and metabolic dysfunctions at adulthood. As both vitamin D and glucocorticoids change adipogenesis, parameters related to metabolism and action of these hormones in the adipocyte can be altered in rats raised in small litters (SL). We also studied the antiobesity effects of high calcium diet since it decreases visceral fat in obesity models. On postnatal day (PN) 3, litter size was adjusted to 3 pups/dam (SL) to induce overfeeding. Control litters (NL) remained with 10 pups/dam until weaning. From PN120 to PN180, half of the SL rats were fed standard chow (SL) and the other half was fed a calcium-supplemented chow (SL-Ca, 10 g CaCO3/kg). Both SL groups were heavier and hyperphagic when compared with the NL group; however, SL-Ca rats ate less than SL. SL-Ca rats had decreased VAT mass and adipocyte size, associated with lower hypothalamic NPY content, VAT fat acid synthase content and leptinemia. At PN120, SL rats had increased plasma 25(OH)D3, Cyp27b1 mRNA and glucocorticoid receptor (GR-α) in the VAT, but lower vitamin D receptor (Vdr) mRNA. At PN180, Cyp27b1 and GR-α remained higher, while Vdr normalized in SL rats. SL-Ca rats had normal VAT Cyp27b1 and GR-α, but lower Vdr. Thus, higher body mass and glucocorticoid receptors in the VAT of SL rats are normalized by calcium-enriched diet, and Vdr expression in this tissue is reduced, suggesting a possible role of glucocorticoids and vitamin D in calcium action in the adipocyte. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess the influence of reduction of the apparent mechanical properties of fully load-bearing porous titanium implants used in mandibular bone defects. Segmental 18 mm long bone defects were created bilaterally in the lower jaws of adult ewes. One group of 6 ewes (group A) was treated with load-bearing ‘rigid’ (high stiffness) porous implants on the right side, and with control on the left side. A second group of 6 ewes (group B) was treated with ‘flexible’ porous and control implants exhibiting apparent mechanical properties ten times lower than the rigid implants. The mechanical behavior of the reconstructed hemi-mandibles was assessed by cantilever testing and bone ingrowth into the segmental defects was assessed by BV/TV measurement within the implant using micro-CT 12 weeks after implantation. A significantly higher rigidity was identified for porous implants compared with control implants at the anterior interface in group B. BV/TV of porous implants was significantly higher than that of control implants in group A. BV/TV differences were significant between porous and control implants in group B and were homogeneous along the main axis. Significantly higher BV/TV was identified in most sub-volumes of group B porous implants compared with group A. This work highlights the critical importance of the tuning of scaffolds to promote bone ingrowth with reference to the local strains occurring within the porous scaffold, which in this application was achieved using fully load-bearing low-stiffness porous titanium implants. [ABSTRACT FROM AUTHOR]

Copyright of International Arab Journal of Dentistry is the property of Saint Joseph University, Faculty of Dental Medicine 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.)

Titanium coating has been widely used as a biocompatible metal in biomedical applications. However, the early cell responses and long-term fixation of titanium implants are not satisfied. To obviate these defects, in this paper, micro-post arrays with various widths (150-1000 μm) and intervals (100-300 μm) were fabricated on the titanium substrate by template-assisted plasma spraying technology. In vitro cell culture experiments showed that MC3T3-E1 cells exhibited significantly higher osteogenic differentiation as well as slightly improved adhesion and proliferation on the micro-patterned coatings compared with the traditional one. The cell number on the pattern with 1000 µm width reached 130% after 6 days of incubation, and the expressions of osteopontin (OPN) as well as osteocalcin (OC) were doubled. No obvious difference was found in cell adhesion on various size patterns. The present micro-patterned coatings proposed a new modification method for the traditional plasma spraying technology to enhance the early cell responses and convenience for the bone in-growth. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluation of some nutrients accumulation including Ni (nickel), Fe (iron), Mg (magnesium), Cu (copper), Ca (calcium) as well as Ni translocation factor (TF) in three tomato cultivars grown hydroponically under treatments including L-histidine (His) and calcium chloride (CaCl2) (300 µM) exposed to nickel (II) sulfate (NiSO4) (150 and 300 µM) by ICP-OES (inductively coupled plasma atomic emission spectroscopy) analysis. Tomato cultivars included Cal-J N3, Early Urbana Y and. Results indicated that shoot Ni accumulation increased under Ni stress. Ca and His reduced root, shoot Ni content and Ni TF (translocation factor) under Ni stress in Petoearly CH cultivar. Ni stress also decreased root and shoot Ca, Fe, Mg and Cu while Ca and His improved the nutrients uptake, and inhibited Ni accumulation. Therefore, Ca and His alleviated adverse effects of Ni stress on nutrients in Petoearly CH cultivar. Beside, Ca and His interaction alleviate Ni stress by inhibition of Ni uptake and translocation as well as plant nutrition improvement in the tomato plants. [ABSTRACT FROM AUTHOR]

Field experiments were conducted in 2006–2007 and 2007–2008 to evaluate the effects of three calcium carbide (CaC2) based formulations (slow release sources of acetylene and ethylene) - matrix-1 [(M-1)(21% CaC2, 58% polyethylene and 21% plaster of paris)], matrix-2 [(M-2)(42% CaC2, 48% polyethylene and 10% plaster of paris)] and paint coated [(PC)(35% CaC2, 44% paint and 21% plaster of paris)] - on nitrification inhibition; growth, yield and nitrogen (N)-uptake of wheat. All the three CaC2formulations (CCF,s) inhibited nitrification, reduced plant height, and improved N-uptake, spike bearing tillers, 1000-grains weight and yield of Inqulab-91 and Bhakhar-02 wheat cultivars. Increase in grain yield was found maximum (22% over the control) with M-1 applied at 30 kg CaC2ha−1; followed by M-2 and PC. Furthermore, CaC2significantly reduced lodging in Bhakhar-02 plots. It is concluded that grain yield of wheat can be enhanced by the application of CaC2formulations particularly M-1 along with NPK fertilizers. [ABSTRACT FROM AUTHOR]

Objective: To assess the impact of maternal obesity and excessive gestational weight gain (GWG) on maternal and neonatal iron status and to explore the possible mediating role of inflammation on hepcidin. Methods: This analysis included 230 pregnant adolescents (13-18 years) enrolled in either a longitudinal or a cross-sectional study. Prepregnancy body mass index (ppBMI) and GWG were obtained from medical records. Maternal iron status (hemoglobin, serum iron, ferritin, transferrin receptor, total body iron, and hepcidin) and inflammation (interleukin-6 [IL-6] and leptin) were assessed at midgestation (26.2 ± 3.3 weeks) in the longitudinal cohort and at delivery (39.8 ± 1.3 weeks) in both study cohorts. Cord blood was collected in both studies and analyzed for iron indicators. Results: Approximately 40% of the adolescents entered pregnancy overweight or obese. Multivariate analysis identified ppBMI as a negative predictor of serum iron at midgestation (P = .009) and a positive predictor of serum hepcidin at delivery (P = .02). None of the other maternal iron status indicators were significantly associated with ppBMI or GWG. Serum IL-6 was significantly positively associated with hepcidin at delivery (P = .0001) but not at midgestation. There was a positive relationship between ppBMI and cord hemoglobin (P = .03). Conclusion: These results suggest that adiposity-related inflammation does not override the iron-mediated signals that regulate hepcidin production during pregnancy, and in this adolescent cohort, there is no strong evidence for a detrimental effect of maternal obesity and excessive weight gain on iron status in the offspring at birth. [ABSTRACT FROM AUTHOR]

Background: Terbium has attracted the attention of researchers and physicians due to the existence of four medically interesting radionuclides, potentially useful for SPECT and PET imaging, as well as for α- and β-radionuclide therapy. The aim of this study was to produce Tb ( T = 17.5 h, E = 1140 keV) and evaluate it in a preclinical setting in order to demonstrate its potential for PET imaging. For this purpose, DOTANOC was used for targeting the somatostatin receptor in AR42J tumor-bearing mice. Methods: Tb was produced by proton-induced spallation of tantalum targets, followed by an online isotope separation process at ISOLDE/CERN. After separation of Tb using cation exchange chromatography, it was directly employed for radiolabeling of DOTANOC. PET/CT scans were performed with AR42J tumor-bearing mice at different time points after injection of Tb-DOTANOC which was applied at variable molar peptide amounts. Lu-DOTANOC was prepared and used in biodistribution and SPECT/CT imaging studies for comparison with the PET results. Results: After purification, Tb was obtained at activities up to ~600 MBq. Radiolabeling of DOTANOC was achieved at a specific activity of 10 MBq/nmol with a radiochemical purity >98 %. The PET/CT scans of mice allowed visualization of AR42J tumor xenografts and the kidneys, in which the radiopeptide was accumulated. After injection of large peptide amounts, the tumor uptake was reduced as compared to the result after injection of small peptide amounts. PET images of mice, which received Tb-DOTANOC at small peptide amounts, revealed the best tumor-to-kidney ratios. The data obtained with Lu-DOTANOC in biodistribution and SPECT/CT imaging studies confirmed the Tb-based PET results. Conclusions: Production of 30-fold higher quantities of Tb as compared to the previously performed pilot study was feasible. This allowed, for the first time, labeling of a peptide at a reasonable specific activity and subsequent application for in vivo PET imaging. As a β-particle-emitting radiolanthanide, Tb would be of distinct value for clinical application, as it may allow exact prediction of the tissue distribution of therapeutic radiolanthanides. [ABSTRACT FROM AUTHOR]

Fundamental aspects of the sorption recovery of rare-earth elements with a sulfocationite from a nitric-phosphoric acid solution formed as intermediate product in the nitric acid processing of Khibiny apatite concentrate were studied. It was confirmed that rare-earth elements can be effectively sorbed from a nitric-phosphoric acid solution without its preliminary neutralization. It was found that polyvalent metals can be sorbed from a nitric-phosphoric acid solution in the form of positively charged (possibly, single-charged) complexes containing nitrate and(or) phosphate ligands. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Cirurgia de Cabeça e Pescoço is the property of Revista Brasileira de Cirurgia de Cabeca e Pescoco 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.)

The flowering of sugarcane ( Saccharum spp. hybrids) is a developmental stage that is desirable for breeding programs but undesirable for commercial cultivation, since it causes losses in sugar content and cane yield. This study aimed to (1) characterise the flowering of four varieties of sugarcane with different flowering times and intensities, (2) determine the nutrient levels in their vegetative apexes and (3) to evaluate the effect of calcium on their flowering. The study was divided into two trials. In the first trial, we tested the effect of planting season on the flowering of four varieties of sugarcane that had contrasting flowering periods. Late or reluctant flowering varieties had higher concentrations of calcium in their vegetative apexes in relation to the early variety. At the same time, the early variety, with heavy flowering, had higher potassium in its vegetative apexes. In the second trial, the effect of calcium on their flowering was tested. The application of calcium on the leaves resulted in its accumulation in the vegetative apexes, causing a reduction in potassium levels in the same tissue. This changed the plant phenology, resulting in a month's delay in flowering and a 50 % reduction in the final flowering intensity. Calcium application by foliar sprays can be used to delay and reduce sugarcane flowering. [ABSTRACT FROM AUTHOR]

A simple iron-catalyzed aerobic oxidative C–C σ-bond cleavage of ketones has been developed. Readily available and environmentally benign air is used as the oxidant. This reaction avoids the use of noble metal catalysts or specialized oxidants, chemoselectively yielding carbon chain-shortened aldehydes, ketones and 1,2-dicarbonyl compounds without overoxidation. [ABSTRACT FROM AUTHOR]

Attachment of human noroviruses to histo blood group antigens is thought to be essential for infection of host cells. Molecular details of the attachment process can be studied in vitro using a variety of NMR experiments. The use of protein NMR based experiments requires assignments of backbone NMR signals. Using uniformly 2H,15N-labeled protruding domains (P-dimers) of a prevalent epidemic human norovirus strain (GII.4 Saga) we have studied the potential of α-l-fucose covalently linked to a rigid lanthanide binding tag to aid backbone assignments using the paramagnetic properties of lanthanide ions. The synthesis of tagged α-l-fucose is reported. Notably, the metal chelating unit connects to the carbohydrate via a triazole linker constructed using click chemistry. [ABSTRACT FROM AUTHOR]

Structures are often subjected to vehicle collision, which can be accidental or intentional as in the case of a terrorist attack. This study investigated the performance of three-story steel moment frames with span length of 5 and 10 m subjected to vehicle collision at a firststory column using finite-element analysis software. The progressive collapse potential of the model structures was evaluated first based on the alternate path approach specified in the published guidelines. The vehicle impact analysis showed that all model structures remained stable when the speed of the vehicle was 40 km=h. However at the speeds of 80 and 120 km=h, progressive collapse occurred at both model structures after collision. The overall damages obtained from collision analysis were significantly larger than those computed based on the sudden column removal approach. [ABSTRACT FROM AUTHOR]

Microstructural and property evolution of 1050 commercial pure aluminum subjected to high-strain-rate deformation (1.2–2.3 × 103 s−1) by split Hopkinson pressure bar (SHPB) and subsequent annealing treatment were investigated. The as-deformed and their annealed samples at 373–523 K were characterized by transmission electron microscopy (TEM) and microhardness tests. TEM observations reveal that the as-deformed sample is mainly composed of a lamellar structure, whose transverse/longitudinal average subgrain/cell sizes are 293 and 694 nm, respectively. The initial coarse grains are refined significantly. The initial lamellar grain structures are subdivided into pancake-shaped subgrains due to a gradual transition by triple junction motion at 473 K, and then a dramatic microstructural coarsening is observed at 523 K. It is suggested that annealing behavior of this dynamic loading structure is better considered as a continuous process of grain coarsening or continuous recovery. [ABSTRACT FROM PUBLISHER]

A novel sort of cellular titanium foam with the porosity of 86–90% and the main-pore size of 0.5–3.0 mm was successfully prepared. Such foam exhibited a compressive curve showing three regimes: the initial elasticity, the middle zigzag plateau, and the final “densification.” This “densification” presented a course that the broken pieces continually accumulated in those pores which were unbroken or not entirely broken. The fracture morphology suggested that the compressive failure was typically brittle for this titanium foam. The electromagnetic shielding performance was investigated in the radio wave frequency range (0.3–3000 MHz) for this foam, which showed an evident effectiveness with a good performance at low frequencies. On the whole, the effectiveness would be superior while the porosity of the sample was relatively small. It could be inferred that the present foam samples would perform their electromagnetic shielding mainly by the reflection loss mechanism in the low-frequency range, and give priority to the absorption loss mechanism at the upper-frequencies. [ABSTRACT FROM PUBLISHER]