scholarly journals Modifying Effects of Some Plant Hormones on Zucchini Cotyledons Subjected to High Temperature and Excess Copper

Botanica ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 28-39
Author(s):  
Ekaterina Stoynova-Bakalova ◽  
Natalia Ivanova ◽  
Dimitar Bakalov ◽  
Liliana Gigova
Keyword(s):  
High Temperature ◽  
Cucurbita Pepo ◽  
Total Activity ◽  
Copper Stress ◽  
Antioxidant Enzyme Activities ◽  
Beneficial Effects ◽  
Excess Copper ◽  
Enzyme Isoforms ◽  
Total Antioxidant ◽  
Better Than

AbstractThe aim of the study was to investigate the potential beneficial effects of exogenous application of methyl jasmonate (MeJa) and phenylurea cytokinin (4PU-30) on zucchini (Cucurbita pepo L.) cotyledons subjected to high temperature (HT) and combined HT plus excess copper (Cu2+) stress. Compared to HT stressed zucchini cotyledons, exposure to excess Cu2+ prior to HT treatment inhibited the growth, decreased superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities, increased glutathione-Stransferase (GST) and peroxidase (Px) total activities, and induced new enzyme isoforms (GST4, GST8, and Px4). The effect of MeJa on the double-stressed plants was to increase SOD, GPx and Px total activities and stimulate the activity of GST8, GST9, GST10, SOD5, Px3 and Px8 isoenzymes. In addition to SOD, GPx and Px, 4PU-30 increased GST total activity, up-regulated Px1 and GR1, and had a higher stimulatory effect on SOD5, Px3, GPx3, GST9 and GST10 activities. Copper, 4PU-30 and MeJa treatments changed the abundance and pattern (MeJa) of soluble zucchini polypeptides in a specific manner. MeJa and especially 4PU-30 applied alone, or in combination, stimulated the growth of later HT-treated cotyledons. 4PU-30 counteracted better than MeJa in the HT+heavy metal-caused inhibition of the growth. The data indicated that both MeJa and 4PU- 30 may protect the zucchini plants from high temperature and combined high temperature plus excess copper stress, but 4PU-30 was more effective; the protective effect was related to the changes in the gene expression, total antioxidant enzyme activities and the activity of individual isoforms of the enzymes.

URANUS 52N

Alloy Digest ◽  
1994 ◽  
Vol 43 (5) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Flue Gas ◽  
Crevice Corrosion ◽  
Heat Treating ◽  
Flue Gas Desulfurization ◽  
Temperature Performance ◽  
Aisi Type ◽  
Better Than

Abstract URANUS 52N is a nitrogen-alloyed duplex stainless steel improved in stress-corrosion cracking resistance and with pitting and crevice corrosion resistance better than AISI Type 317L. Applications include handling phosphoric acid contaminated with chlorides and in flue gas desulfurization scrubbers. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-566. Producer or source: Creusot-Marrel.

Multi-omics analyses on the response mechanisms of ‘Shine Muscat’ grapevine to low degree of excess copper stress (Low-ECS)

2021 ◽  
pp. 117278
Author(s):  
Mengxia Chen ◽  
Xiang Fang ◽  
Zicheng Wang ◽  
Lingfei Shangguan ◽  
Tianhua Liu ◽  
...  
Keyword(s):  
Copper Stress ◽  
Excess Copper ◽  
Low Degree

scholarly journals Effects of Ni Additions on the High Temperature Expansion, Melting and Oxidation Behaviors of Cobalt-Based Superalloys

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 173
Author(s):  
Patrice Berthod ◽  
Lionel Aranda ◽  
Jean-Paul Gomis
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Mechanical Analysis ◽  
Scanning Calorimetry ◽  
Beneficial Effects ◽  
Ni Addition ◽  
High Temperature Expansion ◽  
High Fraction ◽  
Thermal Analysis Techniques ◽  
Ni Additions

Nickel is often added to cobalt-based superalloys to stabilize their austenitic structure. In this work the effects of Ni on several high temperature properties of a chromium-rich cobalt-based alloy reinforced by high fraction of TaC carbides are investigated. Different thermal analysis techniques are used: differential scanning calorimetry (DSC), thermo-mechanical analysis (TMA) and thermogravimetry (TG). Results show that the progressive addition of nickel did not induce great modifications of microstructure, refractoriness or thermal expansion. However, minor beneficial effects were noted, including reduction of the melting temperature range and slight decrease in thermal expansion coefficient. The most important improvement induced by Ni addition concerns the hot oxidation behavior. In this way, introducing several tens wt % Ni in this type of cobalt-based alloy may be recommended.

scholarly journals Fe2O3 enhanced high-temperature arsenic resistance of CeO2–La2O3/TiO2 catalyst for selective catalytic reduction of NOx with NH3

RSC Advances ◽  
2021 ◽  
Vol 11 (16) ◽  
pp. 9395-9402
Author(s):  
Na Wang ◽  
Changfei Ye ◽  
Huidong Xie ◽  
Chang Yang ◽  
Jinhong Zhou ◽  
...  
Keyword(s):  
High Temperature ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Arsenic Resistance ◽  
No Conversion ◽  
Tio2 Catalyst ◽  
Reduction Of Nox ◽  
Better Than

The NO conversion of the CeLa0.5Fe0.2/Ti is obviously better than that of the commercial vanadium-based catalyst with regard to arsenic resistance and it has good N2 selectivity, and good SO2 resistance.

Intracellular distribution of α-galactosidase in leaves of Cucurbita pepo

1979 ◽  
Vol 57 (18) ◽  
pp. 1904-1911 ◽  
Author(s):  
Brian Thomas ◽  
John A. Webb
Keyword(s):  
Cucurbita Pepo ◽  
Developmental Stages ◽  
Molecular Size ◽  
Total Activity ◽  
Intracellular Distribution ◽  
Molecular Forms ◽  
Enzyme Release ◽  
Enzyme Preparations ◽  
Isolated Protoplasts

The intracellular distribution of α-galactosidase in leaves of Cucurbita pepo was studied at different developmental stages using tissue strips, homogenates, and isolated protoplasts. About 85% of the total activity was found in the 500 g supernatant after tissues were homogenized either in water, in buffer at pH 5.6 or at pH 7.0, or in buffer containing 0.8 M KCl. Isolated protoplasts contained less than 10% of the total activity which was confined to the 20 000 g supernatant after lysis. p-Nitrophenyl-α-D-galactoside was readily hydrolysed when incubated with leaf strips but less than 3% of α-galactosidase could be leached from strips held for 4 h in 100 mM phosophate buffer or in buffer containing either 0.8 M KCl, 1 mM EDTA, or 1 mM dithioerythritol. It is concluded that at all stages of leaf development a high proportion of α-galactosidase is located in the exocellular region, not strongly bound either to the outer surface of the plasmalemma or to the cell wall but prevented from diffusing through the wall matrix by some physical attribute such as molecular size. Enzyme release occurred only following breakage or enzymatic digestion of the wall. The in vivo properties of the exocellular enzyme in leaf strips were compared with those of three molecular forms of α-galactosidase (LI, LII, and LIII) which were partially purified from mature leaves. The exocellular enzyme was active over a broad pH range with optima at pH 3.0 and pH 6.0; this resembles a combination of pH optima for LI and LIII. Inhibition by Cu2+ and p-chloromercuribenzoate resembled that for LIII and LII, respectively. Galactose and galactinol at a 5 mM concentration were 25–30% inhibitory for all enzyme preparations; melibiose, raffinose, and stachyose were very weakly inhibitory. The function of an exocellular α-galactosidase and its bearing on the transport of galactosylsucrose oligosaccharides to and from the minor veins of C. pepo are discussed.

Metabolomic alterations associated with copper stress in Cryptococcus neoformans

2021 ◽  
Author(s):  
Tianshu Sun ◽  
Xiaogang Li ◽  
Wei Song ◽  
Shuying Yu ◽  
Linqi Wang ◽  
...  
Keyword(s):  
Cryptococcus Neoformans ◽  
Metabolic Profile ◽  
Pathogenic Fungus ◽  
Copper Toxicity ◽  
Enrichment Analysis ◽  
Copper Stress ◽  
Pathway Enrichment Analysis ◽  
Flight Mass Spectrometry ◽  
Opportunistic Pathogenic ◽  
Better Than

Background: Copper stress is an effective host strategy in resisting the opportunistic pathogenic fungus Cryptococcus neoformans. We studied metabolic changes in C. neoformans under copper stress. Materials & methods: Wild-type and metallothionein-null C. neoformans were treated with copper on agar containing glucose, glycerol or ethanol as the carbon source and their metabolites were analyzed by untarget metabolomics strategy using gas chromatography coupled with time of flight mass spectrometry. Results: The metabolic profile of C. neoformans varied in the presence and absence of copper. Pathway enrichment analysis showed that the differentially abundant metabolites were related to amino acid and carbohydrate metabolism. C. neoformans grown on glycerol or ethanol resisted copper toxicity better than C. neoformans grown on glucose. Conclusion: Copper stress alters the metabolic profile of C. neoformans.

Abstract P228: Do Cardiometabolic Risk Profiles Differ Across Race-Ethnicity? An Analysis of the Most Active U.S. Adults in the 2003-2006 NHANES

Circulation ◽  
2020 ◽  
Vol 141 (Suppl_1) ◽  
Author(s):  
William Boyer ◽  
Michael R Richardson ◽  
James R Churilla ◽  
Lindsay Toth ◽  
Eugene Fitzhugh ◽  
...  
Keyword(s):  
Sex Education ◽  
Ethnic Differences ◽  
Mexican American ◽  
Cardiometabolic Risk ◽  
Total Activity ◽  
Self Report ◽  
Fasting Insulin ◽  
Physiological Factors ◽  
Beneficial Effects ◽  
Race Ethnicity

Introduction: Previous studies have revealed a significant, inverse dose-response relationship between total activity counts/day (TAC/d) and several cardiometabolic risk factors (CMRF). An ongoing line of research is the examination of the contributions of behavioral, environmental, and physiological factors to CMRF differences across race-ethnicity. However, it is unknown if these differences exist among the most physically active adults. Hypothesis: Among the most active U.S. adults, we hypothesize that CMRF measures will differ across race-ethnic groups. Methods: Study sample (n=1,059) included adult (20-79 years of age) participants from the 2003-2006 NHANES who wore an ActiGraph model 7164 accelerometer on the right hip. The top quartile of accelerometer-derived age- and gender-specific TAC/d was used as a cutpoint to define the “most active”. All participants were without T2D (fasting glucose <126 mg/dL, no medication, no self-reported diagnosis) and without CVD (self-report). CMRF included HOMA-IR, fasting insulin and glucose, systolic (SBP) and diastolic blood pressure (DBP), HDL, LDL, triglycerides, BMI, waist circumference (WC) and C-reactive protein (CRP). Multiple linear regression was used to examine CMRF differences between non-Hispanic white (NHW), non-Hispanic black (NHB) and Mexican American (MA) participants. Regression models were adjusted for age, sex, education, smoking, wear time, BMI (except BMI and WC models), objectively-measure MVPA (≥760 counts/min) and race-ethnicity. Results: No significant differences were found in mean TAC/d across race-ethnicity. When compared to NHW, NHB had significantly higher HOMA-IR, fasting insulin, SBP, WC, and BMI. Compared to NHW, MA had significantly higher HOMA-IR, fasting insulin, triglycerides, WC and BMI. When comparing NHB to MA, MA had significantly higher triglycerides and HDL and significantly lower SBP. Conclusions: It has been proposed that the race-ethnic differences in PA participation could be contributing to disparities in elevated CMRF, but even among U.S. adults in the 75th percentile for total activity volume (i.e. TAC/d), race-ethnic differences in CMRF still exist. It is probable that other social, environmental, and genetic factors are responsible for moderating the beneficial effects PA has on CMRF specifically among NHB and MA adults.

Effects of methionine on endogenous antioxidants in the heart

1999 ◽  
Vol 277 (6) ◽  
pp. H2124-H2128 ◽  
Author(s):  
Charita K. Seneviratne ◽  
Timao Li ◽  
Neelam Khaper ◽  
Pawan K. Singal
Keyword(s):  
Antioxidant Enzyme Activities ◽  
Mrna Levels ◽  
Sod Activity ◽  
Time Points ◽  
Physiological Conditions ◽  
Control Value ◽  
Beneficial Effects ◽  
Different Types ◽  
Endogenous Antioxidants ◽  
Gshpx Activity

The deficiency of methionine, an essential amino acid, is associated with cardiovascular lesions. Because different types of cardiac pathologies are caused by a decrease in antioxidants, we examined the effects of methionine on myocardial antioxidant enzymes in hemodynamically assessed rats that were treated with methionine (10 mg/ml) in drinking water for 12, 24, and 48 h. Glutathione peroxidase (GSHPx) activity was significantly increased to 150.5 ± 12.2 and 191.7 ± 13.7% of the control value at 12 and 24 h, respectively, followed by a decline to 120 ± 24.6% at 48 h. The mRNA levels of GSHPx at these time points were 151.2 ± 12.0, 218.7 ± 35.3, and 173.5 ± 25.2%, respectively. Superoxide dismutase (SOD) activity was 144.3 ± 3.7, 114.3 ± 10.1, and 143.1 ± 11.2% at 12, 24, and 48 h, respectively. Catalase (Cat) activity was 272.4 ± 5.4, 237.8 ± 16.6, and 224.1 ± 17.3% of the control value. The expression of Cat and SOD mRNA was unchanged at 12, 24, and 48 h. The lipid peroxidation was decreased by 24.4 ± 11.2, 54.9 ± 0.1, and 6.4 ± 2.1% at 12, 24, and 48 h, respectively. Methionine had no effect on the ventricular or aortic pressures, heart rate, and myocardial glutathione levels at any of the time points. The study shows that methionine has a significant effect on the myocardial antioxidant enzyme activities, and only changes in GSHPx enzyme activity correlated with the mRNA changes. These antioxidant changes may have a role in the beneficial effects of methionine in pathological rather than physiological conditions.

scholarly journals Reversal of age-associated oxidative stress in mice by PFT, a novel kefir product

2020 ◽  
Vol 34 ◽  
pp. 205873842095014
Author(s):  
Mamdooh Ghoneum ◽  
Shaymaa Abdulmalek ◽  
Deyu Pan
Keyword(s):  
Oxidative Stress ◽  
Low Density Lipoprotein ◽  
Redox Homeostasis ◽  
Density Lipoprotein ◽  
Antioxidant Enzyme Activities ◽  
Protective Effects ◽  
Oxidative Stress Biomarkers ◽  
Age Related ◽  
Total Antioxidant ◽  
The Brain

Introduction: Oxidative stress is a key contributor to aging and age-related diseases. In the present study, we examine the protective effects of PFT, a novel kefir product, against age-associated oxidative stress using aged (10-month-old) mice. Methods: Mice were treated with PFT orally at a daily dose of 2 mg/kg body weight over 6 weeks, and antioxidant status, protein oxidation, and lipid peroxidation were studied in the brain, liver, and blood. Results: PFT supplementation significantly reduced the oxidative stress biomarkers malondialdehyde (MDA) and nitric oxide; reversed the reductions in glutathione (GSH) levels, total antioxidant capacity (TAC), and anti-hydroxyl radical (AHR) content; enhanced the antioxidant enzyme activities of glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD); inhibited the liver enzyme levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT); significantly reduced triglyceride (TG), total cholesterol (TC), and low density lipoprotein (LDL) levels; and significantly elevated high density lipoprotein (HDL) levels. Interestingly, PFT supplementation reversed the oxidative changes associated with aging, thus bringing levels to within the limits of the young control mice in the brain, liver, and blood. We also note that PFT affects the redox homeostasis of young mice and that it is corrected post-treatment with PFT. Conclusion: Our findings show the effectiveness of dietary PFT supplementation in modulating age-associated oxidative stress in mice and motivate further studies of PFT’s effects in reducing age-associated disorders where free radicals and oxidative stress are the major cause.

scholarly journals Surface Josephson plasma waves in a high-temperature superconductor

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Qianbo Lu ◽  
Anthony T. Bollinger ◽  
Xi He ◽  
Robert Sundling ◽  
Ivan Bozovic ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperature Superconductor ◽  
Near Field ◽  
Low Loss ◽  
Surface And Interface ◽  
Field Coupling ◽  
Non Invasive ◽  
Crystal Film ◽  
Enhanced Superconductivity ◽  
Better Than

Abstract Electron density oscillations with acoustic dispersions and sustained at boundaries between different media provide information about surface and interface properties of heterostructures. In ultrathin metallic films these plasmonic excitations are heavily damped. Superconductivity is predicted to reduce dissipation allowing detection of these resonances. Emerging low-loss interface Cooper-pair waves have been studied before, however, the observation of surface-confined Josephson plasmons in highly anisotropic superconductors has remained elusive. Here, we report on generation and coupling to these excitations in an ultrathin single-crystal film of high-temperature superconductor La1.85Sr0.15CuO4. The film becomes brighter than Au below the critical temperature when probed with sub-gap THz photons. We show that the enhanced signal in the superconducting state, which can be visualized with a spatial resolution better than λ/3000, originates from near-field coupling of light to surface Josephson plasmons. Our results open a path towards non-invasive investigation of enhanced superconductivity in artificial multilayers, buried interface states in topological heterostructures, and non-linear phenomena in Josephson devices.

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