Concentrations Of Re Research Articles

Experimental Substantiation of Hygientic Regulatory Standards for a Mixture of С6-С10 Saturated Hydrocarbons in the Atmospheric Air of Residential Areas

Toxicity and hazard assessment of the mixture of saturated hydrocarbons C6-C10 (hexane, heptane, octane, nonane, decane)) at a single and chronic exposure was PERFORMED in animal experiments. It was shown that in terms of acute toxicity, the mixture is low hazard, exhibits moderate irritant effect on skin and eye mucous membrane and shows a slight dermal resorptive effect. The threshold limit concentration for a single inhalation exposure (Limac) as estimate4d by the resorptive effect is 5250±mg/m3 At a long 90 day continuous exposure, neuro-, hepato- and embryo toxicity was revealed at a concentration of 160mg/m3. The threshold limit concentration for chronic exposure (Limch) was estimated as 31.4 mg/ m3 and no effect concentration as 5.2 mg/m3. The threshold limit concentration of the mixtu re based on reflex action was estimated on a level of 280 mg/m3. Based on the investigations outcome, the mixture of saturated hydrocarbons C6-C10 is referred to hazard class 3. Maximum allowable concentrations (MACs) in the atmospheric air of residential areas were substantiated: MAC average daily based on resorptive effect equals to 5 mg/m3; MAC maximum single based on reflex action equals to 50 mg/m3.

Concentrations of platinum-group elements (PGE), Re and Au in arsenian pyrite and millerite from Mo–Ni–PGE-Au black shales (Zunyi region, Guizhou Province, China): results from LA-ICPMS study

Lower Cambrian Mo–Ni sulphidic black shales from the Huangjiawan mine (Guizhou Province, south China) have anomalous platinum-group element (PGE) concentrations (up to ∼1 ppm in total). We used LA-ICPMS to study the distribution of PGE in pyrite and Ni-sulphide (millerite) and FE-SEM/EDS for determination of As in pyrite. A sulphide concentrate was produced by innovative hydroseparation techniques from one representative sample, which contained 162 ppb Pt, 309 ppb Pd, 12.2 ppb Ru, 11.3 ppb Rh, 1.5 ppb Ir, 11 212 ppb Re and 343 ppb Au. Mineralogical analysis revealed that pyrite forms ∼12 vol%, which corresponds to a calculated ∼18.4 wt% of all mineral phases in mineralized black shale. We found that pyrite contains on average (144 analyses) 0.10 ppm Pt, 0.11 ppm Re and 1.40 ppm Au (Ru, Rh, Pd, Os and Ir were below detection limit). It also contains from ∼0.5 to ∼1.8 wt% As and can be therefore classified as arsenian pyrite. Millerite (77 analyses) showed PGE, Re and Au values below detection limit. We suggest that pyrite represents a dominant Au carrier, containing between 64 and 83% Au of the total Au mineralised rock budget. Conversely, pyrite does not bear any significant amount of Re and Pt, contributing up to ∼0.2% and ∼12.5% to their whole rock budgets, respectively. Time resolved LA-ICPMS spectra in pyrite indicate that Pt, Re and Au behave as typical lattice-bound elements, with only Re locally forming micro-inclusions. Arsenic is heterogeneously distributed in pyrite and the Au/As ratio (much lower than 0.02) is in support of Au to be structurally bound in solid solution.

Influence of Re Concentration on the Mechanical Properties of Tungsten Borides from First-Principles Calculations

Tungsten borides are promising high-temperature materials. However, the structure and hardening mechanisms of tungsten boride are still great challenges. To solve the problems, we apply the first-principles method to study the structure of WB3 and explore the influence of alloying element Re on the mechanical properties of WB3. The calculated Vickers hardness of WB3 is 39.1 GPa. We further find that a low concentration of Re can improve the hardness of WB3, which is in good agreement with the experimental result. However, the hardness and elastic properties of WB3 decrease gradually with increasing Re concentration. The calculated results show that the structure and hardness of WB3 are attributed to the B–B hexagonal prism. A high concentration of Re weakens the charge interaction between the B–B atoms, and reduces the mechanical properties of WB3. Therefore, we can adjust the alloy concentration to improve the Vickers hardness of transition metal borides.

Influence of high-temperature annealing on morphological and compositional changes of phases in Ni-base single crystal superalloy

Microstructure evolution during high temperature annealing of the CM186LC single crystal nickel-base superalloy in the temperature range of 900–1100°C for up to 2500h was investigated. Microstructural analyses were aimed at observing the changes in morphology of precipitates, in both two dimensions (2D) and three dimensions (3D). The changes in the chemical composition of constituting phases, caused by annealing, were also determined. Although no external stress was applied, after annealing at 1000°C and 1100°C the directional coalescence of the γ' phase in directions parallel to secondary dendrite arms occurred. In the temperature range of 900–1100°C, decomposition of the primary MC carbides took place. The primary carbides were fragmented into small plate-shaped particles, and secondary carbides were also formed. Additionally, in the investigated temperature range, the precipitates of topologically close packed (TCP) phases were found. Those precipitates, plate-like in shape, grew up to a length of several micrometres. Coalescence of the γ′ phase and formation of TCP precipitates during high temperature exposure of CM186LC was accompanied by decreases in the concentrations of Co, Cr, W and Re in the γ phase.

Influence of rhenium on γ′-strengthened cobalt-base superalloys

Abstract

Multi-Elemental Analysis of Crepis Sahendi Boiss Grown in Iraqi Kurdistan Region Using ICP-OES/ICP-MS Techniques

Crepis sahendi Boiss is perennial plant growing in Iraqi Kurdistan region. Traditionally, it is used for the treatment of abdominal ache. The objective of this study is to evaluate the element contents of root, stem, leaf and flower of C. sahendi, which were determined using microwave assisted digestion followed by ICP-OES/ICP-MS techniques. Sixty-five elements were analyzed from the studied plant parts. Element concentrations of Pt, Pd and Re have not been detected in any parts of the studied plant. Some elements were present only in specific parts, such as; Ta, Ti, U, Ho, Lu, Tm, Yb W, In and Te. The rest of the elements were detected in all parts of C. sahendi in different concentrations. Lead and Arsenic reach the toxic concentrations in flower with 45.9 ppm and 25.6 ppm respectively. Chromium was also showed in a toxic ratio within root, leaf and flower with 8.04 ppm, 7.43 ppm and 3.47 ppm respectively. The determination of metals as toxic ratio was depended on the WHO references. The presence of these toxic heavy metals in such a ratio in the selected parts of C. sahendi make us believe that this traditional plant is not safe to be used by consumers in the sampling area.

Mechanism of Apoptosis for Resveratrol-mediated Reversing the Drug-resistance of AML HL-60/ADR cells

To explore the mechanism of apoptosis for resvertrol-mediated reversing the drug-resistance of AML HL-60/ADR cells. The HL-60/ADR cells were divided into 4 groups: control group, adriamycin (ADR)-treated group, resveratrol(Res)-treated group and ADR+Res-treated group. The inhibitory rate of cell proliferation was analyzed by CCK-8 method. The auto-fluorescence intensity of intracellular ADR and the apoptotic rate of HL-60/ADR cells were detected by flow cytometry. The mRNA expression levels of multidrug-resistance associated protein-1(MRP1), anti-apoptotic gene BCL-2 and pro-apoptotic gene BAX were analyzed by real-time fluorescence quantitative RT-PCR. The protein expression levels of MRP1, BCL-2 and BAX were detected by Western blot. The maximal inhibition rates of cell proliferation were 44%, 61%, 76% and 81%, respectively in different concentration of Res (25, 50, 100, 200 µmol/L) and with concentration-dependent manner(r=0.876, P<0.05). Compared with ADR group (IC50: 8.534±1.111 µmol/L), the half inhibitory concentration (IC50) of HL-60/ADR cells [(1.591±0.373) µmol/L] decreased significantly in ADR+Res group(P<0.05). The auto-fluorescence intensity of ADR in HL-60/ADR cells of ADR+Res group increased significantly (P<0.05). The apoptotic rate of HL-60/ADR cells in Res or ADR+Res group increased significantly (P<0.05). The mRNA expression levels of MRP1 and Bcl-2 in Res or ADR+Res groups decreased and BAX increased significantly (P<0.05). The protein expression levels of MRP1 and BCL-2 were decreased, BAX increased significantly in Res or ADR+Res group (P<0.05). Resveratrol shows the effect of reversing the drug resisitance of HL-60/ADR cells in acute myeloid leukemia, possibly via promoting the apoptosis of HL-60/ADR cells and inhibiting the expression of MRP1, which may be related with the inhibition of BCL-2 expression and the promotion of BAX expression.

Platinum-group element geochemistry used to determine Cu and Au fertility in the Northparkes igneous suites, New South Wales, Australia

Recent studies have shown that platinum-group elements (PGE) can be used to constrain the timing of sulfide saturation in evolving felsic systems. In this study, we report trace-element, PGE, Re and Au data for the barren and ore-associated suites of intermediate to felsic rocks from the Northparkes Cu-Au porphyry region, emphasizing the timing of sulfide saturation and its influence on the tenor of the associated hydrothermal mineralization. Two barren suites, the Goonumbla and Wombin Volcanics and associate intrusive rocks, are found in the region. Geochemical modelling shows that the barren suites are dominated by plagioclase-pyroxene fractionation, whereas the ore-associated Northparkes Cu-Au porphyry suite is characterized by plagioclase-amphibole fractionation, which requires the ore-bearing suite to have crystallized from a wetter magma than barren suites. The concentrations of PGE, Re and Au in the barren suites decrease continuously during fractional crystallization. This is attributed to early sulfide saturation with the fraction of immiscible sulfide precipitation required to produce the observed trend, being 0.13 and 0.16wt.% for the Goonumbla and Wombin suites, respectively. The calculated partition coefficients for Au and Pd required to model the observed change in these elements with MgO are well below published values, indicating that R, the mass ratio of silicate to sulfide melt, played a significant role in controlling the rate of decline of these elements with fractionation. Palladium in the ore-associated suite, in contrast, first increases with fractionation then decreases abruptly at 1.2wt.% MgO. The sharp decrease is attributed to the onset of sulfide precipitation. Platinum on the other hand shows a moderate decrease, starting from the highest MgO sample analysed, but then decreasing strongly from 1.2wt.% MgO. The initial Pt decrease is attributed to precipitation of a platinum-group mineral (PGM), probably a Pt-Fe alloy, and the sharp decrease of both Pt and Pd at 1.2wt.% MgO to sulfide saturation. We suggest that the Goonumbla and Wombin suites are barren because early sulfide saturation locked most of the Cu and Au in a sulfide phase in the cumulus pile of a deep parental magma chamber, well before volatile saturation, so that when the magma reached volatile saturation, it did not have access to the Cu and Au. This contrasts with the relatively late sulfide saturation in the ore-associated suite, which was followed shortly afterwards by volatile saturation. Rayleigh fractionation concentrated incompatible Cu and Au by at least a factor of five before volatile saturation. The short crystallization interval between immiscible sulfide and volatile saturation allowed some Au and Cu to be stripped from the evolving magma. Gold, with its higher partition coefficient into immiscible sulfide melts, was more affected than Cu. The result is a Cu-Au deposit. Our study also suggests that Rayleigh fractionation is as at least as important as the initial concentration of chalcophile elements in the parent magma in determining the fertility of felsic magma suites.

Brain Concentration of Ginsenosides and Pharmacokinetics after Oral Administration of Mountain‐cultivated Ginseng

Mountain‐cultivated ginseng (MCG) can be considered a mimic of wild ginseng, whose seeds are sowed artificially, cultivated in the natural environment, and returned to the wild state before being used clinically. Cultivated ginseng (CG) and MCG are mainly used as the commercial material for clinical applications. However, MCG is much more expensive but effective than CG. The aim of this study is to explore the differences in the pharmacokinetics and brain concentration of Rg1, Re, Rb1, and Rd after oral administration of MCG, CG, and pure ginsenosides. An ultra‐performance liquid chromatography‐tandem mass spectrometry method was developed and validated to determine the concentration of the four ginsenosides in rat plasma and brain tissue. Compared with the pure group, the area under the curve (AUC) of all the four ginsenosides for CG and MCG increased. The mean brain concentrations of the four ginsenosides were found to be 10‐ to 15‐fold lower than the corresponding contents in the plasma, and the poor permeability of ginsenosides into blood–brain barrier was indicated by the low concentrations of the four ginsenosides.

Understanding Active Sites in the Water–Gas Shift Reaction for Pt–Re Catalysts on Titania

Pt–Re clusters supported on titania have shown promise as catalysts for the low temperature water–gas shift reaction. However, the enhanced activity of the bimetallic Pt–Re catalyst versus pure Pt is not well understood. In this work, exclusively bimetallic clusters were grown on TiO2(110) by vapor-deposition of Pt on 2 ML Re clusters and Re on 2 ML Pt clusters. Temperature programmed desorption experiments with CO were used to determine the concentration of Re at the surface, given that CO dissociates on Re but not on Pt. Deposition of 2 ML Pt on 2 ML Re resulted in Re core–Pt shell structures, whereas deposition of low coverages (<0.5 ML) of Re on 2 ML Pt resulted in complete diffusion of Re into the Pt clusters. Both of these Pt on Re bimetallic clusters are thermodynamically favored by the lower surface free energy of Pt compared to Re, and both are also more active than pure Pt clusters in the WGS reaction. Postreaction XPS experiments indicate that Re in the Pt on Re clusters is not oxidized under W...

Effects of processing method on the pharmacokinetics and tissue distribution of orally administered ginseng

BackgroundThe use of different methods for the processing of ginseng can result in alterations in its medicinal properties and efficacy. White ginseng (WG), frozen ginseng (FG), and red ginseng (RG) are produced using different methods. WG, FG, and RG possess different pharmacological properties. MethodsWG, FG, and RG extracts and pure ginsenosides were administered to rats to study the pharmacokinetics and tissue distribution characteristics of the following ginsenosides—Rg1, Re, Rb1, and Rd. The concentrations of the ginsenosides in the plasma and tissues were determined using UPLC-MS/MS. ResultsThe rate and extent of absorption of Rg1, Re, Rb1, and Rd appeared to be affected by the different methods used in processing the ginseng samples. The areas under the plasma drug concentration-time curves (AUCs) of Rg1, Re, Rb1, and Rd were significantly higher than those of the pure ginsenosides. In addition, the AUCs of Rg1, Re, Rb1, and Rd were different for WG, FG, and RG. The amounts of Rg1, Re, Rd, and Rb1 were significantly (p<0.05) higher in the tissues than those of the pure ginsenosides. The amounts of Re, Rb1, and Rd from the RG extract were significantly higher than those from the WG and FG extracts in the heart, lungs, and kidneys of the rats. ConclusionOur results show that the use of different methods to process ginseng might affect the pharmacokinetics and oral bioavailability of ginseng as well as the tissue concentrations of Rg1, Re, Rd, and Rb1.

Re-Os Systematics of Löllingite and Arsenopyrite In Granulite-Facies Garnet Rocks: Insights Into the Metamorphic History and Thermal Evolution of the Broken Hill Block During the Early Mesoproterozoic (New South Wales, Australia)

Abstract Lollingite and arsenopyrite aggregates occur in spessartine-almandine garnet rocks (garnetite) metamorphosed to granulite facies, which are spatially associated with Pb-Zn-Ag mineralization in the giant Broken Hill deposit, southern Curnamona Province, New South Wales, Australia. Sulfarsenide and sulfide minerals comprise lollingite and coexisting arsenopyrite ± galena ± tetrahedrite that occur interstitial to garnet crystals. Lollingite formed first while gold-bearing lollingite, which occurs as rare relicts in arsenopyrite, was destroyed to produce arsenopyrite ± detectable micro-inclusions of invisible gold. Standard mineral separation procedures produced pure separates of lollingite, arsenopyrite, and mixtures of arsenopyrite ± lollingite and lollingite ± arsenopyrite. In a plot of 187 Re/ 188 Os versus 187 Os/ 188 Os, samples of lollingite and lollingite ± arsenopyrite have 187 Re/ 188 Os ratios between 6.87 and 7.40 and 187 Os/ 188 Os ratios between 0.8506 and 0.8651, whereas arsenopyrite and arsenopyrite ± lollingite samples have higher 187 Re/ 188 Os ratios (7.14 to 11.32) and more radiogenic 187 Os/ 188 Os ratios (0.8828 to 0.9654). Thirteen analyses of arsenopyrite and arsenopyrite ± lollingite define a Model 1 isochron with an age of 1574 ± 38 Ma (2σ; MSWD = 1.4, initial 187 Os/ 188 Os ratio of 0.666 ± 0.006), whereas the five lollingite and lollingite ± arsenopyrite samples define a Model 1 isochron with an age of 1707 ± 290 Ma (2σ; MSWD = 0.32, initial 187 Os/ 188 Os ratio of 0.652 ± 0.036) that is indistinguishable from the arsenopyrite age. Rhenium and Os contents are extremely high for lollingite and arsenopyrite (Re = 120–475 ppb; Os = 65–345 ppb), likely as a result of concentration of Re and Os in these minerals during granulite-facies metamorphism from the inferred exhalite protolith. Petrographic observations combined with the Model 1 Re-Os ages and literature SHRIMP U-Pb ages of monazite in garnetite suggest that arsenopyrite formed on the retrograde path at the expense of lollingite. Cooling from peak Olarian P-T conditions (∼800 °C at 1602 Ma) to at least 550 °C (first temperature of stability of arsenopyrite) at ca . 1574 Ma occurred at a rate of ∼9 °C/Myr, which is similar to the rate of cooling determined for previously published SHRIMP U-Pb ages from successive monazite generations (McFarlane & Frost 2009). These results are consistent with the late phase of retrograde metamorphism that began between ca . 1590 and 1575 Ma.

Effect of Rare Earth Metals, Sr, and Ti Addition on the Microstructural Characterization of A413.1 Alloy

The present work was performed on A413.1 alloy containing 0.2–1.5 wt% rare earth metals (lanthanum or cerium), 0.05–0.15% Ti, and 0–0.02 wt% Sr. These elements were either added individually or combined. Thermal analysis, image analysis, and electron probe microanalysis were the main techniques employed in the present study. The results show that the use of the depression in the eutectic temperature as a function of alloy modification cannot be applied in the case when the alloy is treated with rare earth metals. Increasing the concentration of RE increases the solidification zone especially in Sr-modified alloys leading to poor feeding ability. This observation is more prominent in the case of Ce addition. Depending upon the amount of added Ti, two RE based intermetallics can be formed: (i) a white phase, mainly platelet-like (approximately 2.5 μm thick), that is rich in RE, Si, Cu, and Al and (ii) a second phase made up of mainly grey sludge particles (star-like) branching in different directions. The grey phase is rich in Ti with some RE (almost 20% of that in the white phase) with traces of Si and Cu. There is a strong interaction between RE and Sr leading to a reduction in the efficiency of Sr as a eutectic Si modifier causing particle demodification.

Resveratrol and Epigallocatechin-3-gallate addition to thawed boar sperm improves in vitro fertilization

Thawing is one of the most delicate process after semen cryopreservation as spermatozoa pass from a dormant metabolic stage to a sudden awakening in cellular metabolism. The rapid oxygen utilization leads to an overproduction of reactive oxygen species that can damage sperm cells, thus causing a significant decrease of fertilizing potential of frozen-thawed spermatozoa. Resveratrol (Res) is a natural grape-derived phytoalexin and Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea (Camellia sinensis); both molecules are known to possess high levels of antioxidant activity. The objective of the present study was to assess the effect of different concentrations of Res (0.5, 1 or 2 mM; Experiment 1) or EGCG (25, 50 or 100 μM; Experiment 2) supplementation to thawing boar semen extender on sperm quality parameters (viability and acrosome integrity) and in vitro fertilization (IVF). Semen after thawing and dilution with three volumes of Beltsville Thawing Solution (BTS), was immediately divided in control group without antioxidants addition (CTR) and either Res or EGCG groups. Sperm viability and acrosome integrity were evaluated in CTR, Res or EGCG groups after 1 h of incubation at 37 °C. The addition of different doses of Res or EGCG to thawing extender for 1 h did not induce any effect on boar sperm viability and acrosome integrity. However, both Res and EGCG treated samples exhibited a significantly higher penetration rate compared with CTR when used for IVF. In particular the treatment with all the EGCG concentrations increased the penetration rate (P < 0.01) while only Res 2 mM induced a significant increase of this parameter (P < 0.01). In addition, EGCG 25 and 50 μM supplementation significantly increased total fertilization efficiency as compared to control (EGCG 25 μM: 40.3 ± 8.2 vs 26.8 ± 9.5, P < 0.05; EGCG 50 μM: 40.4 ± 7.8 vs 26.8 ± 9.5, P < 0.01). The same effect was observed with Res 2 mM (51.0 ± 7.6 vs 29.6 ± 11.3, P < 0.01). In conclusion, our results indicate that the addition of different doses of the two antioxidants to thawed spermatozoa for one hour, even if does not exert any effect on sperm viability and acrosome integrity, efficiently improves in vitro penetration rate. Moreover, both molecules (EGCG 25 and 50 μM and Res 2 mM) significantly increases the total efficiency of fertilization.

Potential accumulation of protopanaxadiol-type ginsenosides in six-months toxicokinetic study of SHENMAI injection in dogs

SHENMAI injection (SMI), derived from famous Shen Mai San, is a herbal injection widely used in China. Ginsenosides are the major components of SMI. To monitor the exposure level of SMI during long-term treatment, a 6-month toxicokinetic experiment was performed. Twenty-four beagle dogs were dived into four groups (n = 6 in each group): a control group (0.9% NaCl solution) and three SMI groups (2, 6 or 3 mg/kg). The dogs were i.v. infused with vehicle or SMI daily for 180 d. Blood samples for analysis were collected at specific time points as follows: pre-dose (0 h); at 10, 30, and 60 min during infusion; and at 10, 30, 60, 90, 120, 240, and 300 min post-administration. Concentrations of ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf, and Rg1 in the plasma were determined simultaneously by liquid chromatography–tandem mass spectrometry. Non-compartmental parameters were further calculated and analyzed. Significant differences were found between the kinetic behavior of 20(S)-protopanaxadiol-type (PPD-type) and 20(S)-protopanaxatriol-type (PPT-type) ginsenosides. Increasing in the exposure level of PPD-type ginsenosides was observed in dogs during the experiment. Therefore, PPD-type ginsenosides are closely related to the immunity modulation effect of SMI. Increased PPD-type ginsenoside exposure level may present potential toxicity and induce drug-drug interaction risks during SMI administration. As such, PPD-type ginsenoside accumulation must be carefully monitored in future SMI research.

Determination of trans-resveratrol and its metabolites in rat serum using liquid chromatography with high-resolution time of flight mass spectrometry.

In this study we developed a sensitive method using high performance liquid chromatography (HPLC) coupled to electrospray ionization (ESI) with high resolution time of flight (TOF) mass spectrometry (MS) for the determination of naturally occurring antioxidant trans-resveratrol (3,5,4'-trihydroxy-trans-stilbene, RES). This method enabled an investigation of a relationship between tumor growth in rats and concentration of RES and its primary metabolites, trans-resveratrol-3-O-sulfate-3-O-sulfate (R3S) and trans-resveratrol-3-O-β-d-glucuronide (R3G), in rat serum after RES exposure (5 or 25mg/kg/day). RES levels in rat serum were near the limit of detection, showing concentrations of 4±1 and 12±4ng/mL for low and high-dose exposure, respectively. Compared to RES, higher concentrations were found for its metabolites (R3G:4.8±0.3 and 6.8±0.3μg/mL; R3S:0.27±0.09 and 0.34±0.04μg/mL, respectively). Using TOF, for the first time, we measured the matrix affected limits of detection (LODs) in plasma (3.7, 82.4, and 4.7ng/mL for RES, R3G, and R3S, respectively), which were comparable to those reported in previous work using HPLC tandem mass spectrometry, but with a benefit of a full mass spectral profile. The ability to acquire data in full scan mode also revealed other isomers of R3S. The additional novelty of our study is in synthesis and application of deuterated recovery standards enabling accurate and precise quantification. In order to develop a robust method, the ESI conditions were optimized using a multilevel full factorial design of experiments.

Microstructure and Superconducting Properties of YBCO Bulk Superconductors With RE Substitutions

The influence of RE ( $\text{RE} = \text{Yb}, \text{Sm}$ ) substitutions on the microstructure and superconducting properties of Y-Ba-Cu-O (YBCO) bulk superconductors has been studied for different RE concentrations and their combinations. Precursor powders $\text{YBa}_{2}\text{Cu}_{3}\text{O}_{7-\delta}$ (Y-123), Y2O3 and CeO2 were enriched with different amounts of Yb2O3 and (or) Sm2O3 powders with the aim to increase critical current density, i.e., $J_{c}$ , in self-field as well as in higher magnetic fields, by introducing additional pinning centers. YBCO bulk superconductors with RE2O3 addition were prepared by the optimized top-seeded melt-growth process in the form of single grains. Microstructure analysis revealed that RE2O3 addition leads to a higher amount of smaller Y2BaCuO5 (Y-211) particles, which is related to high critical current density $(J_{c} \sim 7 \times 10^{4} \text{A/cm}^{2})$ of the samples with RE2O3 addition in low magnetic fields. In this paper, the effect of RE2O3 addition on Y-211 particle size, critical temperature $T_{c}$ , and critical current density $J_{c}$ is reported.

Effect of B-complex vitamins on the antifatigue activity and bioavailability of ginsenoside Re after oral administration

BackgroundBoth ginsenoside Re and B-complex vitamins are widely used as nutritional supplements. They are often taken together so as to fully utilize their antifatigue and refreshing effects, respectively. Whether actually a drug–nutrient interaction exists between ginsenoside Re and B-complex vitamins is still unknown. The objective of this study was to simultaneously investigate the effect of B-complex vitamins on the antifatigue activity and bioavailability of ginsenoside Re after their oral administration. The study results will provide valuable theoretical guidance for the combined utilization of ginseng and B-complex vitamins. MethodsGinsenoside Re with or without B-complex vitamins was orally administered to mice to evaluate its antifatigue effects and to rats to evaluate its bioavailability. The antifatigue activity was evaluated by the weight-loaded swimming test and biochemical parameters, including hepatic glycogen, plasma urea nitrogen, and blood lactic acid. The concentration of ginsenoside Re in plasma was determined by liquid chromatography–tandem mass spectrometry. ResultsNo antifatigue effect of ginsenoside Re was noted when ginsenoside Re in combination with B-complex vitamins was orally administered to mice. B-complex vitamins caused to a reduction in the bioavailability of ginsenoside Re with the area under the concentration–time curve from zero to infinity markedly decreasing from 11,830.85 ± 2,366.47 h·ng/mL to 890.55 ± 372.94 h·ng/mL. ConclusionThe results suggested that there were pharmacokinetic and pharmacodynamic drug–nutrient interactions between ginsenoside Re and B-complex vitamins. B-complex vitamins can significantly weaken the antifatigue effect and decrease the bioavailability of ginsenoside Re when simultaneously administered orally.

Investigation of the potential immunomodulatory effects of resveratrol on equine whole blood: An in vitro investigation

Horses affected with gastrointestinal conditions such as colic or colitis are at substantial risk for translocation of bacterial components such as lipopolysaccharide (LPS, endotoxin) from the gastrointestinal tract into circulation resulting in systemic inflammation and subsequent morbidity and mortality. Therefore, there is a need for effective preventive and treatment strategies aimed at minimizing the host's inflammatory reaction to these pathogen-associated molecular patterns (PAMPs) from gastrointestinal disease. Resveratrol (RES, trans-3,5,4′-trihydroxystilbene) is a phytoalexin commonly found in fruits and beverages, including red wine. Health benefits associated with the consumption of red wine have been attributed to RES. Resveratrol has been significantly shown to exert a powerful anti-inflammatory effect in laboratory animals subjected to experimental endotoxemia/sepsis. Therefore, the objective of this study was to determine in vitro whether RES had an inhibitory effect on the production of tumor necrosis factor (TNF) in cultivated whole blood (Cwb) following stimulation by PAMPs. We hypothesized that RES would inhibit TNF production in Cwb following stimulation by LPS or lipoteichoic acid (LTA). Production of TNF bioactivity in Cwb was measured in the presence of phosphate buffered saline (control), ethanol (solvent control), dexamethasone (anti-inflammatory control), LPS, LTA, and three different concentrations of RES. Both LPS and LTA stimulated TNF production, and addition of dexamethasone was inhibitory to this effect. An anti-inflammatory effect for RES was not demonstrated under the current experimental conditions. Further studies are required to characterize the effect of RES on the equine innate immune system during systemic inflammation.

Rare earth elements in mine, slime, and river waters in the Kavalerovsky and Dalnegorsky districts of the Russian Far East

The concentrations of rare earth elements (REEs) in anthropogenic (mine and slime) and river waters of Kavalerovsky and Dalnegorsky districts of the Far East have been estimated. The highest concentrations of REs have been found in mine water of the Dubrovskoe deposit (Kavalerovsky district), especially in the slime waters of the old tailing dump of the Krasnorechenskaya ore-dressing plant (KODP, Dalnegorsky district). Contamination of the Rudnaya river water has been detected in the vicinity of the KODP old and new tailings dumps. Taking into account that REEs are concomitant with sulfide minerals, the former can be extracted by repeated processing of wastes from the KODP old and new tailings dumps.