33 research outputs found

    Effect of rare earth dopants on structural and mechanical properties of nanoceria synthesized by combustion method

    Get PDF
    Structural characteristics of combustion synthesized, calcined and densified pure and doped nanoceria with tri-valent cations of Er, Y, Gd, Sm and Nd were analyzed by X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). The results showed that the as-synthesized and calcined nanopowders were mesoporous and calculated lattice parameters were close to theoretical ion-packing model. The effect of dopants on elastic modulus, microhardness and fracture toughness of sintered pure and doped ceria were investigated. It was observed that tri-valent cation dopants increased the hardness of the ceria, whereas the fracture toughness and elastic modulus were decreased

    Structural and mechanical properties of La0.6Sr0.4M0.1Fe0.9O3-δ (M: Co, Ni and Cu) perovskites

    Get PDF
    La0.6Sr0.4M0.1Fe0.9O3-δ (M: Co, Ni and Cu) perovskite nanostructures were synthesized using low frequency ultrasound assisted synthesis technique and effect of substitution of Fe by Co, Ni and Cu on crystal structure and mechanical properties in La0.6Sr0.4FeO3-δ perovskite were studied. The HRTEM and Rietveld refinement analyses revealed the uniform equi-axial shape of the obtained nanostructures with the existence of La0.6Sr0.4M0.1Fe0.9O3−δ with mixed rhombohedral and orthorhombic structures. Substitution of Cu decreases the melting point of La0.6Sr0.4FeO3-δ. The results of mechanical characterizations show that La0.6Sr0.4Co0.1Fe0.9O3−δ and La0.6Sr0.4Ni0.1Fe0.9O3−δ have ferroelastic behavior and comparable elastic moduli, however, subtitution of Ni shows higher hardness and lower fracture toughness than Co in Bsite dopin

    Preparation of nanosized yttrium doped CeO2 catalyst used for photocatalytic application

    Get PDF
    In the present work, the pure CeO2 and yttrium doped CeO2 nanopowders were synthesized by the nitrate-fuel self-sustaining combustion method and calcined at 700 C for 2 h. X-ray diffraction (XRD) and high resolution electron transmission microscopy (HRTEM) results demonstrated a cubic fluorite with high purity and the crystallite sizes less than 20 nm calculated from Scherrer’s formula. The BET specific surface area of yttrium doped CeO2 samples showed high values than those of pure CeO2. The photocatalytic activity of yttrium doped CeO2 showed high degradation of Rhodamine B solution under visible light illumination

    Effect of sumac (Rhus Coriaria) on blood lipids: A systematic review and meta-analysis

    No full text
    Cardiovascular diseases (CVD) are the prominent cause of mortality worldwide. Hypercholesterolemia is a chief risk factor for the progress of atherosclerotic vascular disease. Complementary and alternative medicine (CAM) such as herbal interventions has received much attention in literature. Rhus Coriaria (RC) with the general name Sumac is a medicinal spice, especially in Middle Eastern countries which is well known as an anti-lipid spice. This study aimed to summarize the existing findings regarding the effect of RC on the lipid profile. In this review randomized controlled trials (RCTs) assessing the effect of RC on blood lipids were included. Electronic searches using the MeSH terms were conducted in the following databases: Medline, Embase, Scopus, Web of Science and The Cochrane Library. The effect of RC on serum lipid concentration were measured as standardized mean difference (SMD) and 95 confidence intervals (CI) by the random-effects model. The initial search extracted 119 potentially relevant articles. After studying these publications, 4 were potentially eligible and retrieved in full text (four RCTs). Based on the results of the systematic review, RC has positive effects on different indices of the lipid profile including increasing Apo A-I and HDL; decreasing Apo B, Apo B/ Apo A1 ratio, total cholesterol, LDL and triglyceride. However the meta-analysis conducted on three studies on total cholesterol, HDL, LDL and triglyceride individually did not show any significant difference between intervention and control groups. No definite conclusion could be made on the effect of RC on serum blood lipids due to lack of sufficient clinical trials and variable inconsistency. Future trials with desirable designs that would eliminate the limitations in the current evidence are needed before conclusive claims can be made about the effect of RC on the lipid profile. © 201

    Effect of saffron (Crocus sativus L.) and endurance training on mitochondrial biogenesis, endurance capacity, inflammation, antioxidant, and metabolic biomarkers in Wistar rats

    No full text
    We aimed to evaluate the effect of saffron (Crocus Sativus L.) treatment on endurance capacity, mitochondrial biogenesis, inflammation, antioxidant, and metabolic biomarkers in Wistar rats. Forty male rats were allocated equally into four groups: Saffron, Exercise and Saffron, Exercise and Placebo, and Placebo. Endurance training was accomplished on a specified rodent motor-driven treadmill. Running to fatigue test and also metabolic and molecular indices were measured after eight weeks of intervention. mtDNA copy number and NRF-1 gene expression increased significantly in the Ex + S group compared to the exercised and control group (p < 0.05). Endurance capacity time increased in the Ex + S group compared to the Ex group (p < 0.05). Malondialdehyde, CPK, AST, and IL-6 decreased and antioxidant parameters including Glutathione peroxidase and Glutathione increased in the Ex + S group compared to exercised rats (p < 0.01). Saffron enhanced mitochondrial biogenesis, decreased oxidative stress, inflammation, and modulated metabolic biomarkers in exercised rats. Practical applications: The influence of potential nutrient factors on exercise performance has reached much attention in recent years. Athletes require an appropriate sport supplement to reimburse their fatigue and improve their resilience. Saffron (Crocus Sativus L.) is a well-known spice in the food trade which is quite popular around the world by giving a desirable taste to food. In an experimental study, we showed that saffron extract treatment during endurance training could improve endurance capacity by modulating several metabolic and genomic factors. Therefore, by relying on the results of this study and the positive effects of saffron published in previous studies, saffron could be added to sport beverages and supplements to enhance an athlete's performance. © 2019 Wiley Periodicals, Inc

    Effect of omega-3 fatty acid plus vitamin E Co-Supplementation on oxidative stress parameters: A systematic review and meta-analysis

    No full text
    Background & aims: The impact of combined omega-3 FAs and vitamin E supplementation on oxidative stress (OS) has been evaluated in several studies. However the results are inconsistent. Therefore, we performed a systematic review and meta-analysis to assess the role of omega-3 FAplus vitamin E on anti-oxidant and OS parameters. Methods: We searched five databases (PubMed, Embase, Web of Sciences, Scopus and the Cochrane Central Register of Controlled Trials) from inception until March 15th 2018 for RCT covering OS parameters combined with omega-3 FAs and vitamin E. The effect of omega-3 FAs plus vitamin E combination on OS factors was determined as the standardized mean difference (SMD) calculated according to DerSimonian and Laird for the random effects model. Results: Nine articles were included in our analyses, significant improvements were observed in trials supplementing with omega-3 FAs plus vitamin E vs placebo for total antioxidant capacity (TAC) (SMD=0.63, 95CI: 0.31 to 0.95, P<0.001) and nitric oxide (NO) (SMD=0.55, 95CI: 0.23 to 0.87, P<0.001). Significant reduction was observed for malondialdehyde (MDA) (SMD: �0.48, 95CI: �0.68 to �0.28, P<0.001). However, the results of meta-analysis did not show a significant difference in levels of glutathione (GSH) (SMD=0.34, 95CI: �0.07 to 0.75, P=0.10), superoxide dismutase (SOD) activity (SMD: 0.07, 95 CI: �0.58 to 0.73, P=0.82) and Catalase (CAT) activity (SMD: 0.74, 95 CI: �0.30 to 1.79, P=0.16). Conclusion: Co-supplementation with omega-3 FAs and vitamin E increases the levels of NO and TAC, while MDA levels decrease compared to placebo. However, the results showed no significant alterations on GSH concentrations, CAT, and SOD activities. © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolis

    Effect of omega-3 fatty acid plus vitamin E Co-Supplementation on lipid profile: A systematic review and meta-analysis

    No full text
    Background: Dyslipidemia is linked to chronic inflammation, which in return leads to a set of chronic disorders. Omega-3 fatty acids have been reported to reduce inflammation. Furthermore, Vitamin E is a fat-soluble vitamin which has antioxidant and anti-inflammatory effects. Vitamin E and omega-3 fatty acids co-supplementations may be more effective than the single supplementation in control dyslipidemia. Therefore, we designed and conducted the current systematic review and meta-analysis to investigate the effect of co-supplementation of vitamin E and omega-3 fatty acids on the lipid profile. Methods: A comprehensive search for studies published between January 1990 and July 2018 was performed. The initial search extracted 3015 potentially relevant articles. After studying these publications, 9 RCTs were potentially eligible and retrieved in full text. Results: The meta-analysis indicate that on total cholesterol, HDL, LDL and triglyceride individually did not show any significant difference between intervention and control groups, but vitamin E an omega-3 fatty acids co-supplementations significantly reduce VLDL levels. Conclusions: Based on the available evidence, omega-3 fatty acid and vitamin E co-supplementation can reduce VLDL, although its effect on other lipid profile parameters requires more well-designed studies. © 2019 Diabetes Indi

    Effect of omega-3 fatty acid plus vitamin E Co-Supplementation on oxidative stress parameters: A systematic review and meta-analysis

    No full text
    Background & aims: The impact of combined omega-3 FAs and vitamin E supplementation on oxidative stress (OS) has been evaluated in several studies. However the results are inconsistent. Therefore, we performed a systematic review and meta-analysis to assess the role of omega-3 FAplus vitamin E on anti-oxidant and OS parameters. Methods: We searched five databases (PubMed, Embase, Web of Sciences, Scopus and the Cochrane Central Register of Controlled Trials) from inception until March 15th 2018 for RCT covering OS parameters combined with omega-3 FAs and vitamin E. The effect of omega-3 FAs plus vitamin E combination on OS factors was determined as the standardized mean difference (SMD) calculated according to DerSimonian and Laird for the random effects model. Results: Nine articles were included in our analyses, significant improvements were observed in trials supplementing with omega-3 FAs plus vitamin E vs placebo for total antioxidant capacity (TAC) (SMD=0.63, 95CI: 0.31 to 0.95, P<0.001) and nitric oxide (NO) (SMD=0.55, 95CI: 0.23 to 0.87, P<0.001). Significant reduction was observed for malondialdehyde (MDA) (SMD: �0.48, 95CI: �0.68 to �0.28, P<0.001). However, the results of meta-analysis did not show a significant difference in levels of glutathione (GSH) (SMD=0.34, 95CI: �0.07 to 0.75, P=0.10), superoxide dismutase (SOD) activity (SMD: 0.07, 95 CI: �0.58 to 0.73, P=0.82) and Catalase (CAT) activity (SMD: 0.74, 95 CI: �0.30 to 1.79, P=0.16). Conclusion: Co-supplementation with omega-3 FAs and vitamin E increases the levels of NO and TAC, while MDA levels decrease compared to placebo. However, the results showed no significant alterations on GSH concentrations, CAT, and SOD activities. © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolis
    corecore