scholarly journals 475 Heat Treatments Reduce Irradiation-induced Changes in Phenylpropanoid Metabolism in Grapefruit

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 527A-527
Author(s):  
R.E. McDonald ◽  
W.R. Miller ◽  
T.G. McCollum
Keyword(s):  
Heat Treatment ◽  
Fold Increase ◽  
Heat Treatments ◽  
Maximum Activity ◽  
Phenylpropanoid Metabolism ◽  
Total Phenols ◽  
Citrus Paradisi ◽  
Pal Activity ◽  
Canopy Position ◽  
Induced Changes

Irradiation is being evaluated as a quarantine treatment of grapefruit (Citrus paradisi, Macf.), but it can cause damage to the fruit. We wanted to determine if pre-irradiation heat treatments would improve fruit tolerance to irradiation as they improve tolerance to low-temperature injury. `Marsh' grapefruit were harvested from interior and exterior canopy positions and irradiated at 0 or 1.0 kGy at a dose rate of 0.148 kGy·min-1 before storage for 4 weeks at 10 °C. Following storage, pitting of flavedo tissue was the most evident condition defect noted as a result of irradiation. Pitting was noted on 15% and 27% of irradiated interior and exterior canopy fruit, respectively, whereas there was no pitting on non-irradiated fruit. Temperature conditioning before irradiation decreased the susceptibility of fruit to damage. Pitting was 26%, 19%, and 17% when fruit were held 2 h at 20 (ambient), 38 or 42 °C, respectively. There was a marked increase in phenylalanine ammonia-lyase (PAL) activity following irradiation. Maximum activity (≈18-fold increase) was attained 24 h after irradiation. Irradiation-induced PAL activity was reduced significantly by temperature conditioning at 38 or 42 °C. Exterior canopy fruit flavedo contained higher levels of total phenols, including flavanols and coumarins, compared with interior canopy fruit. The deposition of lignin was not related to canopy position. Neither irradiation nor heat treatment had an effect on total phenols or lignin deposition. It seems that irradiation causes a stress condition in the fruit, which leads to pitting of peel tissue. Heat treatment before irradiation reduced the damaging effects of irradiation.

scholarly journals Canopy Position and Heat Treatments Influence Gamma-irradiation-induced Changes in Phenylpropanoid Metabolism in Grapefruit

2000 ◽  
Vol 125 (3) ◽  
pp. 364-369 ◽  
Author(s):  
R.E. McDonald ◽  
W.R. Miller ◽  
T.G. McCollum
Keyword(s):  
Heat Treatment ◽  
Dose Rate ◽  
Free Sterol ◽  
Heat Treatments ◽  
Maximum Activity ◽  
Phenylpropanoid Metabolism ◽  
Total Phenols ◽  
Citrus Paradisi ◽  
Pal Activity ◽  
Canopy Position

Irradiation is being evaluated as a quarantine treatment of grapefruit (Citrus paradisi Macf. `Marsh'), but it can cause damage to the fruit. Research was conducted to determine if preirradiation heat treatments would improve fruit tolerance to irradiation as they improve tolerance to low temperature injury and to determine if canopy position influenced fruit tolerance to irradiation. Initially, grapefruit were irradiated at 0 or 2.0 kGy at a dose rate of 0.14 kGy·min-1 and selected biochemical changes were monitored over time. There was a marked increase in phenylalanine ammonia-lyase (PAL) activity following irradiation. Maximum activity (≈18-fold increase) was attained 24 hours after irradiation. Subsequently, grapefruit were harvested from interior and exterior canopy positions and irradiated at 0 or 1.0 kGy at a dose rate of 0.15 kGy·min-1 before storage for 4 weeks at 10 °C. Following storage, pitting of flavedo was the most evident condition defect noted as a result of irradiation. Pitting was observed on 27% and 15% of irradiated exterior and interior canopy fruit, respectively, whereas there was no pitting on nonirradiated fruit. Heat treatment before irradiation decreased susceptibility of fruit to damage. Pitting was 26%, 19%, and 17% when fruit were held 2 hours at 20 (ambient), 38 or 42 °C, respectively. Irradiation-induced PAL activity was reduced by temperature conditioning at 38 or 42 °C. Exterior canopy fruit flavedo contained higher levels of total phenols, including flavanols and coumarins compared with interior canopy fruit. Deposition of lignin was not related to canopy position. Neither irradiation nor heat treatment had an effect on total phenols or lignin deposition. Generally, cholesterol, campesterol, stigmasterol, β-sitosterol, and isofucosterol were found to be higher in four steryl lipid fractions in exterior canopy fruit compared with interior canopy fruit. Irradiation increased campesterol in the free sterol and steryl glycoside fractions and decreased isofucosterol in the free sterol fraction. Heat treatments had no effect on individual sterol levels. It seems that irradiation causes a stress condition in the fruit, which leads to pitting of peel tissue. Heat treatment before irradiation reduced damaging effects of irradiation.

Microstructural Development in Nb-Ti Multifilamentary Superconductors During Processing

1985 ◽  
Vol 43 ◽  
pp. 190-191
Author(s):  
A. W. West
Keyword(s):  
Heat Treatment ◽  
Critical Current Density ◽  
Copper Matrix ◽  
Wire Drawing ◽  
Heat Treatments ◽  
Microstructural Development ◽  
Final Size ◽  
Density Values ◽  
The Wire ◽  
Multifilamentary Superconductors

The influence of the filament microstructure on the critical current density values, Jc, of Nb-Ti multifilamentary superconducting composites has been well documented. However the development of these microstructures during composite processing is still under investigation.During manufacture, the multifilamentary composite is given several heat treatments interspersed in the wire-drawing schedule. Typically, these heat treatments are for 5 to 80 hours at temperatures between 523 and 573K. A short heat treatment of approximately 3 hours at 573K is usually given to the wire at final size. Originally this heat treatment was given to soften the copper matrix, but recent work has shown that it can markedly change both the Jc value and microstructure of the composite.

Quantitative Microstructural Analysis of a Ni-based Superalloy After Different Heat Treatments

2020 ◽  
Vol 70 (12) ◽  
pp. 4519-4524
Keyword(s):  
Heat Treatment ◽  
Internal Structure ◽  
Microstructural Analysis ◽  
Temperature Treatment ◽  
Heat Treatments ◽  
Metal Melts ◽  
Metallic Inclusions ◽  
Undercooled Melt ◽  
Super Alloy

The efficiency of time-temperature treatment (T-TT) on metal melts can be microstructurally analysed through their degree of purity in non-metallic inclusions. In the case of the Ni-based super alloy under discussion (MSRR 7045) the heat treatment was the undercooling consequences both on the durability of the casting environment (ingots-refractories) and on the internal structure of the metal (porosity, microstructural isotropy). Keywords: time-temperature treatment, undercooled melt, non-metallic inclusions, purity, microstructural isotropy

scholarly journals Proteomic analysis of heat shock proteins in maize (Zea mays L.)

2019 ◽  
Vol 43 (1) ◽  
Author(s):  
Mahmoud Hussien Abou-Deif ◽  
Mohamed Abdel-Salam Rashed ◽  
Kamal Mohamed Khalil ◽  
Fatma El-Sayed Mahmoud
Keyword(s):  
Heat Treatment ◽  
Heat Stress ◽  
Heat Shock ◽  
Heat Shock Proteins ◽  
Proteome Analysis ◽  
High Temperature Stress ◽  
Heat Treatments ◽  
Maize Plants ◽  
Adverse Influence ◽  
Shock Proteins

Abstract Background Maize is one of the important cereal food crops in the world. High temperature stress causes adverse influence on plant growth. When plants are exposed to high temperatures, they produce heat shock proteins (HSPs), which may impart a generalized role in tolerance to heat stress. Proteome analysis was performed in plant to assess the changes in protein types and their expression levels under abiotic stress. The purpose of the study is to explore which proteins are involved in the response of the maize plant to heat shock treatment. Results We investigated the responses of abundant proteins of maize leaves, in an Egyptian inbred line of maize “K1”, upon heat stress through two-dimensional electrophoresis (2-DE) on samples of maize leaf proteome. 2-DE technique was used to recognize heat-responsive protein spots using Coomassie Brilliant Blue (CBB) and silver staining. In 2-D analysis of proteins from plants treated at 45 °C for 2 h, the results manifested 59 protein spots (4.3%) which were reproducibly detected as new spots where did not present in the control. In 2D for treated plants for 4 h, 104 protein spots (7.7%) were expressed only under heat stress. Quantification of spot intensities derived from heat treatment showed that twenty protein spots revealed clear differences between the control and the two heat treatments. Nine spots appeared with more intensity after heat treatments than the control, while four spots appeared only after heat treatments. Five spots were clearly induced after heat treatment either at 2 h or 4 h and were chosen for more analysis by LC-MSMS. They were identified as ATPase beta subunit, HSP26, HSP16.9, and unknown HSP/Chaperonin. Conclusion The results revealed that the expressive level of the four heat shock proteins that were detected in this study plays important roles to avoid heat stress in maize plants.

Influence of Heat Treatment on Microstructure and Mechanical Properties of Selective Laser Melted TiAl6V4 Alloy

2018 ◽  
Vol 284 ◽  
pp. 615-620 ◽  
Author(s):  
R.M. Baitimerov ◽  
P.A. Lykov ◽  
L.V. Radionova
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Selective Laser Melting ◽  
Room Temperature ◽  
Base Alloy ◽  
Tensile Tests ◽  
Heat Treatments ◽  
Laser Melting ◽  
Microstructure And Mechanical Properties ◽  
Treatment Procedures

TiAl6V4 titanium base alloy is widely used in aerospace and medical industries. Specimens for tensile tests from TiAl6V4 with porosity less than 0.5% was fabricated by selective laser melting (SLM). Specimens were treated using two heat treatment procedures, third batch of specimens was tested in as-fabricated statement after machining. Tensile tests were carried out at room temperature. Microstructure and mechanical properties of SLM fabricated TiAl6V4 after different heat treatments were investigated.

Influence of Laser Heat Treatment on Fracture Strength of Ceramic Thin Film

2012 ◽  
Vol 566 ◽  
pp. 145-149
Author(s):  
Hirotaka Tanabe ◽  
Keiji Ogawa ◽  
Yui Izumi ◽  
Tohru Takamatsu ◽  
Heisaburo Nakagawa ◽  
...  
Keyword(s):  
Thin Films ◽  
Heat Treatment ◽  
Fracture Strength ◽  
Strength Loss ◽  
Substrate Material ◽  
Laser Quenching ◽  
Ceramic Thin Films ◽  
Film Hardness ◽  
Induced Changes ◽  
Substrate Hardness

In our previous study, it has been shown that improvement of the adhesive strength and substrate hardness of ceramic coated steels without compromising the film hardness can be achieved by applying laser quenching. In the present research, in order to demonstrate further development of this method, the fracture strength of laser-irradiated ceramic thin films (CrAlN, TiAlN and CrN) was investigated by sphere indentation testing. To prevent heat-induced changes in the substrate hardness, a cemented carbide WC-Co rather than steel was used as substrate material. While the fracture strength of each film decreased significantly through furnace heat treatment, it remained almost unchanged in case of the laser irradiated films. Laser quenching has been shown to effectively reduce the fracture strength loss of the ceramic thin films in coated steels.

Intestinal permeability in allergic rats: nerve involvement in antigen-induced changes

1993 ◽  
Vol 264 (4) ◽  
pp. G617-G623 ◽  
Author(s):  
S. E. Crowe ◽  
K. Soda ◽  
A. M. Stanisz ◽  
M. H. Perdue
Keyword(s):  
Intestinal Permeability ◽  
Fold Increase ◽  
Serum Levels ◽  
Baseline Period ◽  
Antigen Challenge ◽  
51Cr Edta ◽  
Neural Factors ◽  
Induced Changes ◽  
In Vivo Uptake

In vivo uptake of the probe 51Cr-labeled EDTA from the jejunum of egg albumin (EA)-sensitized rats was compared with controls at baseline and after intraluminal antigen challenge. Probe recovery in blood was 60-80% greater in sensitized animals during the baseline period, suggesting that sensitization resulted in increased intestinal permeability. Sensitized, but not control, rats demonstrated a 15-fold increase in 51Cr-EDTA uptake after intraluminal antigen; no change occurred with an unrelated protein. Macromolecular recovery was also enhanced in sensitized animals, since serum levels of immunoreactive EA were elevated 14-fold compared with controls. Antigen challenge was accompanied by biochemical (protease release) and morphological (reduced numbers) evidence of mast cell degranulation in sensitized rats. The neurotoxin tetrodotoxin (applied directly to ligated jejunal segments) inhibited EA-induced uptake of 51Cr-EDTA and antigen. In isolated jejunum from sensitized rats, tetrodotoxin reduced secretory responses to luminal, but not serosal, antigen. These results indicate that neural factors may influence the uptake of molecules from the gut lumen during intestinal anaphylaxis.

scholarly journals Application of Heating on the Antioxidant and Antibacterial Properties of Malaysian and Australian Stingless Bee Honey

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1365
Author(s):  
Nurul Ainaa Farhanah Mat Ramlan ◽  
Aina Syahirah Md Zin ◽  
Nur Fatihah Safari ◽  
Kim Wei Chan ◽  
Norhasnida Zawawi
Keyword(s):  
Heat Treatment ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Antibacterial Properties ◽  
Antibacterial Activities ◽  
Heat Treatments ◽  
Stingless Bee ◽  
Total Phenolic ◽  
Antioxidant Power

In the honey industry, heat treatments are usually applied to maintain honey’s quality and shelf life. Heat treatment is used to avoid crystallisation and allow the easy use of honey, but treatment with heat might affect the antioxidant and antibacterial activities, which are the immediate health effects of honey. This study will determine the effect of heat treatment on Malaysian and Australian stingless bee honey (SBH) produced by the common bee species in both countries. Eighteen honey samples were subjected to heat at 45 °C, 55 °C and 65 °C for one hour and subsequently analysed for their total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and minimum inhibitory concentration (MIC). The results show that all samples had high TPC, TFC and antioxidant activities before the treatment. The heat treatments did not affect (p < 0.05) the TPC, TFC and antioxidant activities in most samples, but did inhibit the antibacterial activities consistently in most of the samples, regardless of the bee species and country of origin. This study also confirms a strong correlation between TPC and TFC with FRAP activities for the non-heated and heated honey samples (p < 0.05). Other heat-sensitive bioactive compounds in SBH should be measured to control the antibacterial properties present.

scholarly journals Electron Beam Melting of Ti-6Al-4V Lattice Structures; Correlation between Post Heat Treatment and Mechanical Properties

2021 ◽  
Author(s):  
Giuseppe Del Guercio ◽  
Manuela Galati ◽  
Abdollah Saboori
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Computer Aided Design ◽  
Mechanical Performance ◽  
Industrial Applications ◽  
Heat Treatments ◽  
Layer By Layer ◽  
Lattice Structures ◽  
Heat Treated ◽  
Aided Design

Abstract Additive Manufacturing processes are considered advanced manufacturing methods. It would be possible to produce complex shape components from a Computer-Aided Design model in a layer-by-layer manner. Lattice structures as one of the complex geometries could attract lots of attention for both medical and industrial applications. In these structures, besides cell size and cell type, the microstructure of lattice structures can play a key role in these structures' mechanical performance. On the other hand, heat treatment has a significant influence on the mechanical properties of the material. Therefore, in this work, the effect of the heat treatments on the microstructure and mechanical behaviour of Ti-6Al-4V lattice structures manufactured by EBM was analyzed. The main mechanical properties were compared with the Ashby and Gibson model. It is very interesting to notice that a more homogeneous failure mode was found for the heat-treated samples. The structures' relative density was the main factor influencing their mechanical performance of the heat-treated samples. It is also found that the heat treatments were able to preserve the stiffness and the compressive strength of the lattice structures. Besides, an increment of both the elongation at failure and the absorbed energy was obtained after the heat treatments. Microstructure analysis of the heat-treated samples confirms the increment of ductility of the heat-treated samples with respect to the as-built one.

scholarly journals Effects of 1-Methylcyclopropene and Heat Treatments on Ripening and Postharvest Decay in `Golden Delicious' Apples

2003 ◽  
Vol 128 (1) ◽  
pp. 120-127 ◽  
Author(s):  
Robert A. Saftner ◽  
Judith A. Abbott ◽  
William S. Conway ◽  
Cynthia L. Barden
Keyword(s):  
Heat Treatment ◽  
Cold Storage ◽  
Ethylene Production ◽  
Titratable Acidity ◽  
Heat Treatments ◽  
Penicillium Expansum ◽  
Colletotrichum Acutatum ◽  
Peel Color ◽  
Golden Delicious ◽  
Force Profile

Prestorage heat, CA storage, and pre- and poststorage treatments with the ethylene action inhibitor, 1-methylcyclopropene (MCP), were tested for their efficacy at inhibiting fungal decay and maintaining quality in `Golden Delicious' apples [Malus sylvestris (L.) Mill. Yellow Delicious Group] stored 0 to 5 months at 0 °C and 7 days at 20 °C. Before storage in air at 0 °C, preclimacteric fruit were treated with either MCP at a concentration of 1 μL·L-1 for 17 hours at 20 °C, 38 °C air for 4 days, MCP plus heat, or left untreated. Some sets of untreated fruit were stored in a controlled atmosphere of 1.5 kPa O2 and 2.5 kPa CO2 at 0 °C while other sets were removed from cold storage in air after 2.5 or 5 months, warmed to 20 °C, and treated with 1 μL·L-1 MCP for 17 hours. Prestorage MCP, heat, MCP plus heat treatments and CA storage decreased decay severity caused by wound-inoculated Penicillium expansum Link, Botrytis cinerea Pers.:Fr., and Colletotrichum acutatum Simmonds (teleomorph Glomerella acutata J.C. Guerber & J.C. Correll sp.nov.). Poststorage MCP treatment had no effect on decay severity. Both prestorage MCP treatment and CA storage delayed ripening as indicated by better retention of green peel color, titratable acidity, and Magness-Taylor flesh firmness, and the reduced respiration, ethylene production rates, and volatile levels that were observed upon transferring the fruit to 20 °C. The prestorage MCP treatment delayed ripening more than CA storage. Following 5 months cold storage, the prestorage MCP treatment maintained the shape of the compression force/deformation curve compared with that of fruit at harvest, as did CA storage, but at a lower force profile. The heat treatment had mixed effects on ripening: it hastened loss of green peel color and titratable acidity, but maintained firmness and delayed increases in respiration, ethylene production and volatile levels following cold storage. The MCP plus heat treatment inhibited ripening more than heat treatment alone but less than MCP treatment alone. In one of 2 years, the MCP plus heat treatment resulted in superficial injury to some of the fruit. Results indicated that MCP may provide an effective alternative to CA for reducing decay severity and maintaining quality during postharvest storage of `Golden Delicious' apples. Prestorage heat to control decay and maintain quality of apples needs further study, especially if used in combination with MCP.

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