scholarly journals High temperature perception in leaves promotes vascular regeneration in distant tissues

2021 ◽  
Author(s):  
Phanu T Serivichyaswat ◽  
Kai Bartusch ◽  
Martina Leso ◽  
Constance Musseau ◽  
Akira Iwase ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Elevated Temperatures ◽  
Callus Formation ◽  
Effect Of Temperature ◽  
Asymmetric Effect ◽  
Ambient Temperatures ◽  
Graft Healing ◽  
Vascular Regeneration ◽  
Xylem Formation ◽  
Temperature Enhancement

Cellular regeneration in response to wounding is fundamental to maintain tissue integrity. Various internal factors including hormones and developmental pathways affect wound healing but little is known about how external factors influence regeneration. To better understand how the environment affects regeneration, we investigated the effects of temperature using the horticulturally relevant process of plant grafting. We found that elevated temperatures accelerated vascular regeneration of Arabidopsis thaliana and tomato (Solanum lycopersicum) grafts. Leaves were critical for this effect since blocking auxin transport or mutating PHYTOCHROME INTERACTING FACTOR4 (PIF4) or YUCCA2/5/8/9 in the cotyledons abolished the temperature enhancement. However, these perturbations had no effect upon graft healing at ambient temperatures and mutations in PIF4 did not affect the temperature enhancement of callus formation or tissue adhesion, suggesting that leaf-derived auxin was specific for enhancing vascular regeneration in response to elevated temperatures. Tissue-specific perturbations of auxin response using a BODENLOS (BDL) mutant revealed an asymmetric effect of temperature upon regeneration: the presence of bdl above the cut prevented temperature enhancement whereas the presence of bdl below the cut prevented graft healing regardless of temperature. Promotion of tissue regeneration by elevated temperatures was not specific for graft healing and we found that elevated temperatures accelerated xylem formation between the parasite Phtheirospermum japonicum and host Arabidopsis thaliana, and this effect required shoot-derived auxin from the parasite. Taken together, our results identify a pathway by which elevated temperatures accelerate vascular development which could be of relevance for improving regeneration and better understanding inter-plant vascular connections.

scholarly journals Temperature-mediated tribological characteristics of 40CrNiMoA steel and Inconel 718 alloy during sliding against Si3N4 counterparts

Friction ◽  
2020 ◽  
Author(s):  
Liuyang Bai ◽  
Shanhong Wan ◽  
Gewen Yi ◽  
Yu Shan ◽  
Sang The Pham ◽  
...  
Keyword(s):  
Inconel 718 ◽  
Friction And Wear ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Effect Of Temperature ◽  
Large Temperature ◽  
Structural Adaptation ◽  
Temperature Dependent ◽  
Inconel 718 Alloy ◽  
Ambient Temperatures

AbstractA comparative evaluation of the friction and wear behaviors of 40CrNiMoA steel and Inconel 718 alloy sliding against Si3N4 counterparts was conducted over a large temperature range from room temperature (RT) to 800 °C. The temperature-dependent tribological properties associated with the resulting chemical mitigation and structural adaptation of the solid sliding surface were clarified by surface/interface characterizations. The results revealed desirable performance in reducing friction and wear at elevated temperatures, which was associated with the resulting oxide composite film’s adaptive lubricating capability, whereas severe abrasive wear occurred at room/ambient temperatures. The oxidative-abrasive differentials for the two alloys were further discussed by considering the combined effect of temperature and stressed-shearing conditions.

Effect of Temperature, Velocity Gradient and I.V. Heparin on in Vitro Blood Coagulation and Platelet Aggregation

1967 ◽  
Vol 17 (01/02) ◽  
pp. 112-119 ◽  
Author(s):  
L Dintenfass ◽  
M. C Rozenberg
Keyword(s):  
Blood Coagulation ◽  
Velocity Gradient ◽  
Elevated Temperatures ◽  
Morphological Changes ◽  
Effect Of Temperature ◽  
Clotting Time ◽  
Progressive Change ◽  
Aggregation Of Platelets ◽  
Microscopic Techniques

SummaryA study of blood coagulation was carried out by observing changes in the blood viscosity of blood coagulating in the cone-in-cone viscometer. The clots were investigated by microscopic techniques.Immediately after blood is obtained by venepuncture, viscosity of blood remains constant for a certain “latent” period. The duration of this period depends not only on the intrinsic properties of the blood sample, but also on temperature and rate of shear used during blood storage. An increase of temperature decreases the clotting time ; also, an increase in the rate of shear decreases the clotting time.It is confirmed that morphological changes take place in blood coagula as a function of the velocity gradient at which such coagulation takes place. There is a progressive change from the red clot to white thrombus as the rates of shear increase. Aggregation of platelets increases as the rate of shear increases.This pattern is maintained with changes of temperature, although aggregation of platelets appears to be increased at elevated temperatures.Intravenously added heparin affects the clotting time and the aggregation of platelets in in vitro coagulation.

scholarly journals Molecular and physiological characterization of the effects of auxin-enriched rootstock on grafting

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Longmei Zhai ◽  
Xiaomin Wang ◽  
Dan Tang ◽  
Qi Qi ◽  
Huseyin Yer ◽  
...  
Keyword(s):  
Callus Formation ◽  
Ethylene Biosynthesis ◽  
Union Formation ◽  
Biosynthetic Gene ◽  
Graft Union ◽  
Specific Expression ◽  
Physiological Characterization ◽  
Graft Healing ◽  
Expression Of Genes ◽  
Or Gene

AbstractsGrafting is a highly useful technique, and its success largely depends on graft union formation. In this study, we found that root-specific expression of the auxin biosynthetic gene iaaM in tobacco, when used as rootstock, resulted in more rapid callus formation and faster graft healing. However, overexpression of the auxin-inactivating iaaL gene in rootstocks delayed graft healing. We observed increased endogenous auxin levels and auxin-responsive DR5::GUS expression in scions of WT/iaaM grafts compared with those found in WT/WT grafts, which suggested that auxin is transported upward from rootstock to scion tissues. A transcriptome analysis showed that auxin enhanced graft union formation through increases in the expression of genes involved in graft healing in both rootstock and scion tissues. We also observed that the ethylene biosynthetic gene ACS1 and the ethylene-responsive gene ERF5 were upregulated in both scions and rootstocks of the WT/iaaM grafts. Furthermore, exogenous applications of the ethylene precursor ACC to the junction of WT/WT grafts promoted graft union formation, whereas application of the ethylene biosynthesis inhibitor AVG delayed graft healing in WT/WT grafts, and the observed delay was less pronounced in the WT/iaaM grafts. These results demonstrated that elevated auxin levels in the iaaM rootstock in combination with the increased auxin levels in scions caused by upward transport/diffusion enhanced graft union formation and that ethylene was partially responsible for the effects of auxin on grafting. Our findings showed that grafting success can be enhanced by increasing the auxin levels in rootstocks using transgenic or gene-editing techniques.

The Interaction of Temperature and Bending Load on Structural Performance of Chinese Larch Wood

2012 ◽  
Vol 531-532 ◽  
pp. 122-126
Author(s):  
Hai Bin Zhou ◽  
Chuan Shuang Hu ◽  
Jian Hui Zhou
Keyword(s):  
Elevated Temperatures ◽  
Coupling Effect ◽  
Structural Performance ◽  
Effect Of Temperature ◽  
Short Exposure ◽  
Short Exposure Time ◽  
Larch Wood ◽  
Timber Construction ◽  
Bending Load ◽  
Stress Levels

Wood is being used extensively in timber construction in China. In fire-resistant design for timber construction, the main goal is to ensure that enough structural integrity is maintained during a fire to prevent structure collapse. It is important to understand its structural performance when exposed to elevated temperatures and loaded by stress levels. To study the interaction effect of Chinese larch wood, a total of 72 small clear wood samples were observed under constant stress levels when the wood temperature was elevated. The results indicated that Chinese larch wood was more susceptible to the coupling effect of temperature and stress. The interaction promoted a temporary stable flexural structure to collapse during a short exposure time.

Characterization and regulation of cold-induced heat shock protein expression in mouse brown adipose tissue

1995 ◽  
Vol 269 (1) ◽  
pp. R38-R47 ◽  
Author(s):  
J. M. Matz ◽  
M. J. Blake ◽  
H. M. Tatelman ◽  
K. P. Lavoi ◽  
N. J. Holbrook
Keyword(s):  
Adipose Tissue ◽  
Heat Shock ◽  
Brown Adipose Tissue ◽  
Cold Exposure ◽  
Elevated Temperatures ◽  
Uncoupling Protein ◽  
Hsp70 Expression ◽  
Mitochondrial Uncoupling ◽  
Ambient Temperatures ◽  
Brown Adipose

The accumulation of heat shock proteins (HSPs) after the exposure of cells or organisms to elevated temperatures is well established. It is also known that a variety of other environmental and cellular metabolic stressors can induce HSP synthesis. However, few studies have investigated the effect of cold temperature on HSP expression. Here we report that exposure of Institute of Cancer Research (ICR) mice to cold ambient temperatures results in a tissue-selective induction of HSPs in brown adipose tissue (BAT) coincident with the induction of mitochondrial uncoupling protein synthesis. Cold-induced HSP expression is associated with enhanced binding of heat shock transcription factors to DNA, similar to that which occurs after exposure of cells or tissues to heat and other metabolic stresses. Adrenergic receptor antagonists were found to block cold-induced HSP70 expression in BAT, whereas adrenergic agonists induced BAT HSP expression in the absence of cold exposure. These findings suggest that norepinephrine, released in response to cold exposure, induces HSP expression in BAT. Norepinephrine appears to initiate transcription of HSP genes after binding to BAT adrenergic receptors through, as yet, undetermined signal transduction pathways. Thermogenesis results from an increase in activity and synthesis of several metabolic enzymes in BAT of animals exposed to cold challenge. The concomitant increase in HSPs may function to facilitate the translocation and activity of the enzymes involved in this process.

Performance and Reliability of MEMS Gyroscopes and Packaging at High Temperatures

2010 ◽  
Vol 2010 (HITEC) ◽  
pp. 000359-000366 ◽  
Author(s):  
Patrick McCluskey ◽  
Chandradip Patel ◽  
David Lemus
Keyword(s):  
High Temperature ◽  
Indoor Environment ◽  
Elevated Temperatures ◽  
High Sensitivity ◽  
Effect Of Temperature ◽  
Gps Tracking ◽  
Mems Gyroscope ◽  
Mems Gyroscopes ◽  
Gyroscope Sensor

Elevated temperatures can significantly affect the performance and reliability of MEMS gyroscope sensors. A MEMS vibrating resonant gyroscope measures angular velocity via a displacement measurement which can be on the order on nanometers. High sensitivity to small changes in displacement causes the MEMS Gyroscope sensor to be strongly affected by changes in temperature which can affect the displacement of the sensor due to thermal expansion and thermomechanical stresses. Analyzing the effect of temperature on MEMS gyroscope sensor measurements is essential in mission critical high temperature applications, such as inertial tracking of the movement of a fire fighter in a smoke filled indoor environment where GPS tracking is not possible. In this paper, we will discuss the development of the high temperature package for the tracking application, including the characterization of the temperature effects on the performance of a MEMS gyroscope. Both stationary and rotary tests were performed at room and at elevated temperatures on 10 individual single axis MEMS gyroscope sensors.

Reliability Testing on a Multilayer Chip Inductor Fabricated From a Ferrite With a 350 °C Curie Point

2011 ◽  
Vol 2011 (HITEN) ◽  
pp. 000014-000020 ◽  
Author(s):  
James Galipeau ◽  
George Slama
Keyword(s):  
Curie Point ◽  
Elevated Temperatures ◽  
Core Loss ◽  
Effect Of Temperature ◽  
Electrical Parameters ◽  
Hole Energy ◽  
Magnetic Components ◽  
Additional Testing ◽  
And Performance ◽  
Curie Temperatures

As more electronics are used in down-hole energy exploration, under the hood automotive applications, and in other environments where temperatures exceed 200 °C; there is a need for compact passive magnetic components that operate reliably at elevated temperatures. Most ferrites used to make multi layer ceramic inductors have Curie temperatures in the 100–200 °C range. As temperatures rise above the Curie point ferrites lose their magnetic properties and become paramagnetic. This means that traditional multi-layer ceramic inductors suffer severe performance degradation when operated at elevated temperatures. Therefore, ferrite materials with higher Curie temperatures need to be developed to increase device performance and reliability at these high temperatures. In this work inductors were made from a low-temperature, co-fire compatible, ferrite with a Curie temperature of 350 °C. The inductors were first subjected to a 1000 hour life test at 300 °C during which the electrical parameters were found to change no more than 4 %. The inductance, resistance, core loss, and saturation flux density of the inductors were measured at various temperatures. Additional testing focused on the effect of temperature on the device's frequency profile and performance changes under thermal cycling and thermal shock.

scholarly journals Effect of Temperature and Sisal Fiber Content on the Properties of Plaster of Paris

2018 ◽  
Vol 7 (4.20) ◽  
pp. 205 ◽  
Author(s):  
Aqil M. ALmusawi ◽  
Thulfiqar S. Hussein ◽  
Muhaned A. Shallal
Keyword(s):  
Mechanical Properties ◽  
Elevated Temperatures ◽  
Physical And Mechanical Properties ◽  
Fiber Content ◽  
Sisal Fiber ◽  
Effect Of Temperature ◽  
Plaster Of Paris ◽  
Micro Cracks ◽  
Recent Developments ◽  
Negative Effect

Recent developments in the production of ecologically friendly building composites have led to a renewed interest in the use of vegetable fibers as a reinforcement element. Traditional pure Plaster of Paris (POP) can suffer from the development of micro-cracks due to thermal expansion. Therefore, sisal fiber was studied for its potential as an ecological element to restrict and delay the development of micro-cracks in POP. Different sisal proportions of 0, 2, 4, 6, 8 and 10 wt. % of POP were used to characterize the physical and mechanical properties of POP at the ambient temperature. Then, the effects of temperatures of 25, 100, 200, 300, 400 and 500  were investigated. Results proved that the composite of 10% sisal fiber had the best mechanical properties. Also, when the fiber content was increased, the composite’s performance was enhanced, becoming better able to resist elevated temperatures. However, raising the temperature to 300 or above had a negative effect on the mechanical properties, which were significantly decreased due to the degradation of the sisal fiber. 

scholarly journals The effect of temperature on reproduction in the summer and winter annual Arabidopsis thaliana ecotypes Bur and Cvi

2014 ◽  
Vol 113 (6) ◽  
pp. 921-929 ◽  
Author(s):  
Ziyue Huang ◽  
Steven Footitt ◽  
William E. Finch-Savage
Keyword(s):  
Arabidopsis Thaliana ◽  
Effect Of Temperature ◽  
Winter Annual
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