Antioxidant capacity is correlated with susceptibility to leaf spot caused by a rapid temperature drop in Saintpaulia (African violet)

AbstractSatellite-derived daily sea surface temperature (SST) products are compared with moored SST observations on the West Florida Shelf during the time period of Hurricane Irma. Most of the SST products compare reasonably well with the moored data at the location of 25-m depth, where SST dropped by about 1°C after the hurricane passage. However, most of the SST products did not show the rapid SST drop at the location of 50-m depth where the surface water was cooled by about 4°C within 1 day in response to the hurricane passage. This finding has important implications to air-sea interaction studies and hurricane simulations, in which SST data play an important role. The limitations of the popular satellite products call for additional coastal ocean observations as well as proper inclusion of the real-time observations in satellite-derived products.

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Acute morphological changes of palisade cells ofSaintpaulia leaves induced by a rapid temperature drop

Journal of Plant Research ◽

10.1007/bf02344482 ◽

1996 ◽

Vol 109 (3) ◽

pp. 339-342 ◽

Cited By ~ 16

Author(s):

Jae Gill Yun ◽

Takahiro Hayashi ◽

Susumu Yazawa ◽

Tetzuya Katoh ◽

Yuko Yasuda

Keyword(s):

Morphological Changes ◽

Temperature Drop ◽

Rapid Temperature ◽

Palisade Cells

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Analysis of the Residual Stress and Deformation in a Steel Tube due to Quenching Process Using Different Media

Volume 9: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2014-38701 ◽

2014 ◽

Author(s):

Pratik Sarker ◽

Uttam K. Chakravarty

Keyword(s):

Residual Stress ◽

Temperature Drop ◽

Three Dimensional ◽

Interaction Model ◽

Steel Tube ◽

Time Varying ◽

Steel Tubes ◽

Rapid Temperature ◽

Stress And Deformation ◽

Residual Stress And Deformation

Steel tubes are widely used in industries as machine components and are most common in heavily loaded mechanisms subjected to high dynamic torsional and compressive stress. Hence, they should have higher strength than that of the conventional mechanisms to resist failure. Quenching, an industrial heat treatment process, can improve the microstructure, hardness, toughness, and corrosion and wear resistance of materials. Steel tubes, if quenched, would have desired properties to serve the purposes. However, besides improving material properties, quenching generates some residual stress and deformation in the material due to rapid temperature drop and phase transformation. Therefore, to estimate the temperature distribution, residual stress, and deformation computationally; a three-dimensional fluid-structure interaction model is developed for the steel tube with different quenchants. The quenching characteristics by water, brine, and propylene glycol are estimated and compared with each other. The time-varying nodal temperature distributions in the tube are observed and the critical regions are identified having maximum residual stress and deformation. The time-varying residual stress and deformation at a particular point and along the axial and radial directions of the tube are studied. The convergence of the model is checked and validation of the model is done.

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Abrupt and irreversible reduction of chlorophyll fluorescence associated with leaf spot in Saintpaulia (African violet)

Scientia Horticulturae ◽

10.1016/s0304-4238(97)00068-x ◽

1998 ◽

Vol 72 (3-4) ◽

pp. 157-169 ◽

Cited By ~ 3

Author(s):

J.G Yun ◽

T Hayashi ◽

S Yazawa ◽

T Katoh ◽

Y Yasuda

Keyword(s):

Chlorophyll Fluorescence ◽

Leaf Spot ◽

African Violet ◽

Irreversible Reduction

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Diurnal changes in leaf spot sensitivity of Saintpaulia (African violet)

Scientia Horticulturae ◽

10.1016/s0304-4238(97)00019-8 ◽

1997 ◽

Vol 70 (2-3) ◽

pp. 179-186 ◽

Cited By ~ 1

Author(s):

J.G. Yun ◽

T. Hayashi ◽

S. Yazawa

Keyword(s):

Leaf Spot ◽

Diurnal Changes ◽

African Violet

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Thermal behaviour of edible crab Cancer pagurus Linnaeus, 1758 in coastal Norway

Fauna norvegica ◽

10.5324/fn.v39i0.2738 ◽

2019 ◽

Vol 39 ◽

pp. 1-11

Author(s):

Snorre Bakke ◽

Sten I Siikavuopio ◽

Jørgen Schou Christiansen

Keyword(s):

Temperature Drop ◽

Decapod Crustacean ◽

Horizontal Gradient ◽

Light Cycle ◽

Preferred Temperature ◽

Cancer Pagurus ◽

Significant Difference ◽

Lower Critical Temperature ◽

Righting Reflex ◽

Rapid Temperature

Ocean warming drives latitudinal shifts in the distribution of ectotherm species. The rate and magnitude of such shifts are constrained by physiology and behavioural thermoregulation. Here, we investigated the thermal preference and lower critical temperature (CTmin) in female edible crab Cancer pagurus, a decapod crustacean with an ongoing northward dispersal along the Norwegian coast. The temperature selected by individual crabs from a northern (latitude ~69°N) and southern (latitude ~62°N) location was examined in a horizontal gradient (5.5-14.5°C) under a simulated day and night light regime. Irrespective of origin, crabs showed pronounced responses to the light cycle – during the day crabs stayed inactive in the warm end of the gradient but during night they actively explored the entire gradient. A preferred temperature of ~13 °C (measured as mode of loggings) was identified for crabs at both locations. Righting reflex experiments of crabs exposed to a rapid temperature drop (7 - 1 °C at -0.1 °C/min) identified a CTmin of ~1.3 °C (i.e., the temperature at which 50% of crabs failed to right from an up-side-down position), and with no significant difference between locations (p > 0.05). Our results provide important information about the functional characteristics of edible crab, and are discussed in context of the biology and ongoing northward dispersal of the species.

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Trans-resveratrol supplement lowers lipid peroxidation responses of exercise in male Wistar rats

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000654 ◽

2020 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Masoud Nasiri ◽

Saja Ahmadizad ◽

Mehdi Hedayati ◽

Tayebe Zarekar ◽

Mehdi Seydyousefi ◽

...

Keyword(s):

Lipid Peroxidation ◽

Antioxidant Capacity ◽

Total Antioxidant Capacity ◽

Wistar Rats ◽

Enzymatic Antioxidants ◽

Acute Response ◽

Total Antioxidant ◽

Male Wistar Rats ◽

Exercise Induced ◽

And Control

Abstract. Physical exercise increases free radicals production; antioxidant supplementation may improve the muscle fiber’s ability to scavenge ROS and protect muscles against exercise-induced oxidative damage. This study was designed to examine the effects of all-trans resveratrol supplementation as an antioxidant to mediate anti-oxidation and lipid per-oxidation responses to exercise in male Wistar rats. Sixty-four male Wistar rats were randomly divided into four equal number (n = 16) including training + supplement (TS), training (T), supplement (S) and control (C) group. The rats in TS and S groups received a dose of 10 mg/kg resveratrol per day via gavage. The training groups ran on a rodent treadmill 5 times per week at the speed of 10 m/min for 10 min; the speed gradually increased to 30 m/min for 60 minutes at the end of 12th week. The acute phase of exercise protocol included a speed of 25 m/min set to an inclination of 10° to the exhaustion point. Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) activity, non-enzymatic antioxidants bilirubin, uric acid, lipid peroxidation levels (MDA) and the total antioxidant capacity (TAC) were measured after the exercise termination. The data were analyzed by using one-way ANOVA. The result showed that endurance training caused a significant increase in MDA level [4.5 ± 0.75 (C group) vs. 5.9 ± 0.41 nmol/l (T group)] whereas it decreased the total antioxidant capacity [8.5 ± 1.35 (C group) vs. 7.1 ± 0.55 mmol/l (T group)] (p = 0.001). In addition, GPx and CAT decreased but not significantly (p > 0.05). The training and t-resveratrol supplementation had no significant effect on the acute response of all variables except MDA [4.3 ± 1.4 (C group) vs. 4.0 ± 0.90 nmol/l (TS group)] (p = 0.001) and TAC [8.5 ± 0.90 (C group) vs. 6.6 ± 0.80 mmol/l (TS group)] (p = 0.004). It was concluded that resveratrol supplementation may prevent exercise-induced oxidative stress by preventing lipid peroxidation.

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The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000116 ◽

2012 ◽

Vol 82 (3) ◽

pp. 228-232 ◽

Cited By ~ 7

Author(s):

Mauro Serafini ◽

Giuseppa Morabito

Keyword(s):

Antioxidant Capacity ◽

Dietary Intervention ◽

Ex Vivo ◽

The Body ◽

Dietary Polyphenols ◽

Enzymatic Antioxidant ◽

Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

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