Two Phases of Ageing in Drosophila Subobscura

1961 ◽  
Vol 38 (3) ◽  
pp. 679-684
Author(s):  
JEAN M. CLARKE ◽  
J. MAYNARD SMITH
Keyword(s):  
Steady State ◽  
Life Span ◽  
Low Temperatures ◽  
Initial Value ◽  
Male And Female ◽  
Higher Temperature ◽  
Two Phases ◽  
Lower Temperature ◽  
The Individual

1. Male and female D. subobscura were kept for varying periods at low temperatures 3-20° C.) and then transferred to a higher temperature (26-30° C.) and kept there until they died. 2. It was found that during the early part of the life span, over the range 15-30° C., every day spent at a low temperature reduced the expectation of life at a higher temperature by approximately 1 day. Later, when the expectation of life at the higher temperature had fallen to about half its initial value, little further change in this expectation occurred with increasing age at a lower temperature. 3. It is concluded that the life span can be divided into two phases, (i) an irreversible ‘ageing’ process whose rate is approximately independent of temperature from 15 to 30° C., but which is slower at 3° C., and (ii) a ‘dying’ process which is initiated when ageing has proceeded to a stage at which the individual is no longer capable of maintaining a steady state at the temperature at which it is living, although the same individual would be capable of maintaining a steady state at some lower temperature. 4. The rate of the dying process is highly dependent on temperature, and it can be reversed in flies transferred to lower temperatures.

Steady State Conduction Behaviour of Liquid Crystalline Polyurethane

2013 ◽  
Vol 856 ◽  
pp. 210-214
Author(s):  
Jitender Kumar Quamara ◽  
Satish Kumar Mahna ◽  
Sohan Lal ◽  
Pushkar Raj
Keyword(s):  
Activation Energy ◽  
Steady State ◽  
Temperature Region ◽  
Liquid Crystalline ◽  
Ionic Conduction ◽  
Schottky Type ◽  
Order Of Magnitude ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Type Conduction

The steady state measurements in Liquid crystalline polyurethane (LCPU) have been investigated for different fields (4 - 45 kV/cm) and temperatures (50°-220°C). The nature of conduction processes has been determined by estimating ion jump distances (a) and Schottky coefficients. The order of magnitude of a in the temperature region 150°C and below does not seem to support an ionic conduction. However the magnitude of a at higher temperatures (180°C and above) indicates the possibility of ionic conduction. There is a definite possibility of a Schottky type conduction at lower temperature and a Poole Frankel type conduction at higher temperature (100°C). The activation energy associated with the high temperature region lies between 0.26 eV and 0.65 eV depending on the field whereas in the low temperature region the activation energy lies between 0.82 eV and 0.95 eV depending on the applied electric field. The dual slopes in the log I versus 1/T curves indicate the presence of more than one type of trapping levels.

Dinitrogen fixation in pea beans (Phaseolus vulgaris) as affected by growth stage and temperature regime

1981 ◽  
Vol 59 (7) ◽  
pp. 1181-1188 ◽  
Author(s):  
R. J. Rennie ◽  
G. A. Kemp
Keyword(s):  
Phaseolus Vulgaris ◽  
Temperature Regime ◽  
Low Temperatures ◽  
Growth Stage ◽  
Dry Weight ◽  
Growing Season ◽  
The Other ◽  
Higher Temperature ◽  
Reducing Activity ◽  
Lower Temperature

Tolerance of beans (Phaseolus vulgaris L.) to low temperatures is essential for growth under Canadian growing conditions. At air temperatures typical of a southern Alberta growing season (10–23 °C), 'Aurora' fixed 433 mg N per plant, more than 'Sanilac' and 'Comtesse,' which averaged 307 mg N per plant, and 'Kentwood,' which fixed the least: 214 mg N per plant. At a higher temperature regime (15–23 °C), typical of a southern Ontario growing season, 'Aurora' again fixed the most N2 (456 mg N per plant), while the other three cultivars fixed an average of 370 mg N per plant. The amount of N2 fixed increased as the time to reach maximum acetylene (C2H2) reducing activity lengthened. This suggested that it may be advantageous to select beans that have a longer vegetative stage to prolong the time of active N2 fixation within the limits of acceptable season length to ensure maturity. 'Aurora' was not affected by the lower temperature regime, and although these temperatures delayed the initiation of N2 fixation by 21 days, 'Aurora' compensated by producing 26% greater nodule dry weight and 40% higher maximum C2H2-reducing activity than that observed at the higher temperature regime. Growth and N2 fixation of the other three cultivars were adversely affected by the lower temperature regime, not because of lower nodule numbers or mass but because of lower nodule activity. The good root growth of 'Aurora' at low temperatures may explain its superiority for N2 fixation at lower temperatures. C2H2 reduction and nodule dry weight were acceptable indicators of N2 fixation only during early plant growth when all nodules were new and uniformly active. The ideal time to select the bean cultivars for N2-fixing ability was just before the peak of maximum C2H2-reducing activity and corresponded to the stage from buds-near-breaking to anthesis for both temperature regimes. Molar ratios of C2H2 reduced to N2 fixed suggested that the relative efficiency of N2 fixation varied with temperature and growth stage but not with bean cultivar.

scholarly journals PHOTODYNAMIC HEMOLYSIS AT LOW TEMPERATURES

1954 ◽  
Vol 37 (3) ◽  
pp. 301-311 ◽  
Author(s):  
Harold F. Blum ◽  
Elizabeth Flagler Kauzmann
Keyword(s):  
Solid State ◽  
Low Temperatures ◽  
Room Temperature ◽  
Photosensitized Oxidation ◽  
Higher Temperature ◽  
Semi Solid ◽  
Lower Temperature ◽  
Dye Molecule

It is shown that photodynamic hemolysis may occur at –79°C. if the erythrocytes are suspended in a solution containing 70 per cent glycerol which prevents hemolysis by freezing; but that there is no hemolysis under the same conditions at –210°C. At the higher temperature the viscosity of the solution is still low enough to permit appreciable movement of molecules, whereas at the lower temperature the molecules must be virtually immobile. The findings are compatible with the idea that the dye molecule acts in a cycle, bringing about successive oxidations by O2 molecules, as has been shown for photodynamic hemolysis at room temperature. The assumption of a combination between dye, O2, and substrate does not explain photosensitized hemolysis in the semi-solid state. The mechanism of photosensitized oxidation by O2 is discussed.

The Free Responsible Action of the Individual

2018 ◽  
Author(s):  
Michael P. DeJonge
Keyword(s):  
The Novel ◽  
Extreme Situation ◽  
The Third ◽  
Third Phase ◽  
Responsible Action ◽  
Action Type ◽  
Two Phases ◽  
The Individual ◽  
The Church

If, as Chapter 12 argues, much of Bonhoeffer’s resistance thinking remains stable even as he undertakes the novel conspiratorial resistance, what is new in his resistance thinking in the third phase? What receives new theological elaboration is the resistance activity of the individual, which in the first two phases was overshadowed by the resistance role played by the church. Indeed, as this chapter shows, Bonhoeffer’s conspiratorial activity is associated with what he calls free responsible action (type 6), and this is the action of the individual, not the church, in the exercise of vocation. As such, the conspiratorial activity is most closely related to the previously developed type 1 resistance, which includes individual vocational action in response to state injustice. But the conspiratorial activity differs from type 1 resistance as individual vocational action in the extreme situation.

scholarly journals Sprouting of Sorghum (Sorghum bicolor [L.] Moench): Effect of Drying Treatment on Protein and Starch Features

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 407 ◽  
Author(s):  
Mia Marchini ◽  
Alessandra Marti ◽  
Claudia Folli ◽  
Barbara Prandi ◽  
Tommaso Ganino ◽  
...  
Keyword(s):  
Food Production ◽  
Cost Effective ◽  
High Exposure ◽  
Effective Technology ◽  
Drying Treatment ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The One ◽  
Drying Conditions ◽  
Sorghum Bicolor L

The nutritional and physicochemical properties of sorghum proteins and starch make the use of this cereal for food production challenging. Sprouting is a cost-effective technology to improve the nutritional and functional profile of grains. Two drying treatments were used after sorghum sprouting to investigate whether the drying phase could improve the protein and starch functionalities. Results showed that the drying treatment at lower temperature/longer time (40 °C for 12 h) extended the enzymatic activity that started during sprouting compared to the one performed at higher temperature/shorter time (50 °C for 6 h). An increased protein hydrolysis and water- and oil-holding capacity were found in the flour obtained by the former treatment. Higher protein matrix hydrolysis caused high exposure of starch to enzymes, thus increasing its digestibility, while worsening the technological functionality. Overall, modulating drying conditions could represent a further way, in addition to sprouting, to improve sorghum flour’s nutritional profile.

scholarly journals Traits that influence longevity in mice: a second look.

Genetics ◽  
1992 ◽  
Vol 132 (1) ◽  
pp. 229-239
Author(s):  
K B Dear ◽  
M Salazar ◽  
A L Watson ◽  
R S Gelman ◽  
R Bronson ◽  
...  
Keyword(s):  
Life Span ◽  
Genetic Factors ◽  
Viral Infections ◽  
Genetic Interactions ◽  
Chromosome 9 ◽  
Chromosome 4 ◽  
Histological Findings ◽  
Male And Female ◽  
Female Genotype ◽  
Dominant Black

Abstract Analysis of genetic interactions in the F2 of an intercross of (C57BL/6 x DBA/2) F1J revealed influences of genetic factors on life span. Females lived longer than males. Dilute brown females died sooner than females of other colors. H-2b/H-2b males died sooner than H-2b/H-2d or H-2d/H-2d males, except that among dilute brown males those of typeH-2b/H-2d died sooner. Cluster analysis suggested that male and female genotypes each fall into two groups, with female dilute brown mice having shorter lives than other females, and male H-2b/H-2b mice except dilute brown and dilute brown H-2b/H-2d mice having shorter lives than other males. The association of heterozygosity with life span was clearer in females than in males, yet the longest-lived female genotype was homozygous H-2d/H-2d, of dominant Black phenotype at the Brown locus of chromosome 4, and homozygous dd at the Dilute locus of chromosome 9. The shortest-lived females were dilute brown H-2b/H-2b. The longest-lived and shortest-lived male genotypes were dilute brown H-2d/H-2d and dilute brown H-2b/H-2d, respectively. Although histological findings at postmortem differed between the sexes, there was no association of particular disorders with other genetic markers. The importance of H-2 in males was confirmed, but the allelic effects were perturbed, possibly by the absence of Sendai infection in this experiment. Overall our studies suggest that genetic influences on life span involve interactions between loci, and allelic interactions may change with viral infections or other environmental factors.

MICROSTRUCTURAL EVOLUTION OF Al-Cu-Mg-Ag ALLOY WITH TRACE Zr ADDITION DURING TWO-STEP HOMOGENIZATION

2009 ◽  
Vol 23 (06n07) ◽  
pp. 855-862 ◽  
Author(s):  
FEIYUE MA ◽  
ZHIYI LIU
Keyword(s):  
Melting Point ◽  
Grain Boundaries ◽  
Microstructural Evolution ◽  
Cast Alloy ◽  
Scanning Calorimetry ◽  
Zr Addition ◽  
Homogenization Time ◽  
The Matrix ◽  
Higher Temperature ◽  
Lower Temperature

The microstructural evolution in an Al - Cu - Mg - Ag alloy with trace Zr addition during homogenization treatment was characterized by Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDS). It was shown that the low-melting-point phase segregating toward grain boundaries is Al 2 Cu , with a melting point of 523.52°C. A two-step homogenization process was employed to optimize the microstructure of the as-cast alloy, during which the alloy was first homogenized at a lower temperature, then at a higher temperature. After homogenized at 420°C for 6 h, Al 3 Zr particles were finely formed in the matrix. After that, when the alloy was homogenized at an elevated temperature for a longer time, i.e., 515°C for 24 h, most of the precipates at the grain boundaries were removed. Furthermore, the dispersive Al 3 Zr precipitates were retained, without coarsening greatly in the final homogenization step. A kinetics model is employed to predict the optimal homogenization time at a given temperature theoretically, and it confirms the result in present study, which is 420°C/6h+515°C/24h.

scholarly journals Disrupt-Then-Reframe is in the Air: A French Replication and Refinement

2015 ◽  
Vol 19 (2) ◽  
pp. 162-173
Author(s):  
Roxane Saint-Bauzel ◽  
Audrey Pelt ◽  
Laura Barbier ◽  
Valérie Fointiat
Keyword(s):  
Target Behaviour ◽  
Communication Situation ◽  
Two Phases ◽  
The Individual ◽  
Persuasive Effect

Abstract Initiated by Davis and Knowles (1999), the-disrupt-then-reframe technique is based on the linking of two moments in time. First of all, slipping an unexpected element into a communication situation that is likely to provoke a disruption in communication. Once this disruption has been achieved, proposing a target behaviour by insisting on the benefit that the individual could derive from it. We wanted to verify that this technique, effective in American, Dutch, and Polish contexts and naturally dependent on the culture of individuals and the communication norms which prevail there, could be effective in a French context. In accordance with the literature, our results show that when the two phases of the technique are linked, a greater persuasive effect is observed. A theoretically interesting way to interpret the effectiveness of the technique is proposed.

scholarly journals Research on the Static Recrystallization and Precipitation Behaviors of a V-N Microalloyed Steel

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Baochun Zhao ◽  
Tan Zhao ◽  
Guiyan Li ◽  
Qiang Lu
Keyword(s):  
Static Recrystallization ◽  
Microalloyed Steel ◽  
Time Interval ◽  
Main Role ◽  
Recrystallization Process ◽  
Compression Tests ◽  
Double Compression ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Temperature Strain

Double compression tests were performed on a Gleeble-3800 thermomechanical simulator to study the softening behaviors of deformed austenite in a V-N microalloyed steel. The static recrystallization volume fractions were calculated by stress offset method, and the kinetic model of static recrystallization was constructed. The effects of temperature, strain, and time interval on the softening behaviors were analyzed, and the interactions between precipitation and recrystallization were discussed. The results show that the softening behaviors of the deformed austenite at lower temperature or higher temperature are markedly different. At the temperature of 850°C or 800°C, pinning effects of the precipitates play the main role, and the recrystallization process is inhibited, which leads to the formation of plateaus in the softening curves. An increase in strain promotes the precipitation and recrystallization processes while reduces the inhibition effect of precipitation on recrystallization as well.

scholarly journals INHERITED TASTES AND ENDOGENOUS LONGEVITY

2017 ◽  
Vol 23 (2) ◽  
pp. 674-698 ◽  
Author(s):  
Luciano Fanti ◽  
Luca Gori ◽  
Cristiana Mammana ◽  
Elisabetta Michetti
Keyword(s):  
Steady State ◽  
Overlapping Generations ◽  
Standard Of Living ◽  
Poverty Trap ◽  
Individual State ◽  
State Of Health ◽  
Tax Rate ◽  
Public Investments ◽  
The Individual ◽  
Endogenous Longevity

This article aims at studying a general equilibrium model with overlapping generations that incorporates inherited tastes (aspirations) and endogenous longevity. The existence of standard-of-living aspirations transmitted between two subsequent generations in a context where the individual state of health depends on public investments in health has some remarkable consequences at the macroeconomic level. First, aspirations allow escaping from the well-known poverty trap scenario described by Chakraborty (2004). Second, the steady-state equilibrium may be destabilized through a super-critical Neimark–Sacker bifurcation when the health tax rate is set at too high or too low a level. This causes endogenous fluctuations in income and longevity.

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