scholarly journals Temperature transcends partner specificity in the symbiosis establishment of a cnidarian

2020 ◽  
Vol 15 (1) ◽  
pp. 141-153 ◽  
Author(s):  
Marcela Herrera ◽  
Shannon G. Klein ◽  
Sara Campana ◽  
Jit Ern Chen ◽  
Arun Prasanna ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
Red Sea ◽  
Photochemical Efficiency ◽  
Thermal Conditions ◽  
Effect Of Temperature ◽  
Host Genotype ◽  
Psii Photochemical Efficiency ◽  
And Performance ◽  
Increasing Temperature

AbstractCoral reef research has predominantly focused on the effect of temperature on the breakdown of coral-dinoflagellate symbioses. However, less is known about how increasing temperature affects the establishment of new coral-dinoflagellate associations. Inter-partner specificity and environment-dependent colonization are two constraints proposed to limit the acquisition of more heat tolerant symbionts. Here, we investigated the symbiotic dynamics of various photosymbionts in different host genotypes under “optimal” and elevated temperature conditions. To do this, we inoculated symbiont-free polyps of the sea anemone Exaiptasia pallida originating from Hawaii (H2), North Carolina (CC7), and the Red Sea (RS) with the same mixture of native symbiont strains (Breviolum minutum, Symbiodinium linucheae, S. microadriaticum, and a Breviolum type from the Red Sea) at 25 and 32 °C, and assessed their ITS2 composition, colonization rates, and PSII photochemical efficiency (Fv/Fm). Symbiont communities across thermal conditions differed significantly for all hosts, suggesting that temperature rather than partner specificity had a stronger effect on symbiosis establishment. Overall, we detected higher abundances of more heat resistant Symbiodiniaceae types in the 32 °C treatments. Our data further showed that PSII photophysiology under elevated temperature improved with thermal pre-exposure (i.e., higher Fv/Fm), yet, this effect depended on host genotype and was influenced by active feeding as photochemical efficiency dropped in response to food deprivation. These findings highlight the role of temperature and partner fidelity in the establishment and performance of symbiosis and demonstrate the importance of heterotrophy for symbiotic cnidarians to endure and recover from stress.

Role of natural day-length and temperature in determination of summer and winter diapause in Pieris melete (Lepidoptera: Pieridae)

2011 ◽  
Vol 102 (3) ◽  
pp. 267-273 ◽  
Author(s):  
H.J. Xiao ◽  
S.H. Wu ◽  
H.M. He ◽  
C. Chen ◽  
F.S. Xue
Keyword(s):  
Adaptive Significance ◽  
Field Conditions ◽  
Day Length ◽  
Effect Of Temperature ◽  
Path Coefficient ◽  
Path Coefficient Analysis ◽  
Summer Diapause ◽  
Increasing Temperature

AbstractUnder field conditions, the cabbage butterfly, Pieris melete, displays a pupal summer diapause in response to relatively low daily temperatures and gradually increasing day-length during spring and a pupal winter diapause in response to the progressively shorter day-length. To determine whether photoperiod is ‘more’ important than temperature in the determination of summer and winter diapause, or vice versa, the effects of naturally changing day-length and temperature on the initiation of summer and winter diapause were systematically investigated under field conditions for five successive years. Field results showed that the incidence of summer diapause significantly declined with the naturally increasing temperature in spring and summer generations. Path coefficient analysis showed that the effect of temperature was much greater than photoperiod in the determination of summer diapause. In autumn, the incidence of diapause was extremely low when larvae developed under gradually shortening day-length and high temperatures. The incidence of winter diapause increased to 60–90% or higher with gradually shortening day-length combined with temperatures between 20.0°C and 22.0°C. Decreasing day-length played a more important role in the determination of winter diapause induction than temperature. The eco-adaptive significance of changing day-length and temperature in the determination of summer and winter diapause was discussed.

scholarly journals Experimental observations of fluidized beds at high temperatures

2016 ◽  
Vol 1 (1) ◽  
pp. 9 ◽  
Author(s):  
Paola Lettieri ◽  
David Newton ◽  
John G. Yates
Keyword(s):  
High Temperatures ◽  
Dominant Role ◽  
Effect Of Temperature ◽  
Interparticle Forces ◽  
Collapse Time ◽  
Experimental Values ◽  
Increasing Temperature ◽  
Fcc Catalysts

<p>The objective of this paper is to report some experimental observations on the effect of temperature on the fluidization of three fresh FCC catalysts and an equilibrium (E-cat) FCC. The bed collapse test was used as a quantitative test to characterise the <em>fluidization quality </em>of these materials with increasing temperatures. It provides a sensitive and discriminating means of assessing the changes in the materials’ responses between low and high temperature fluidization. The standardised collapse time, SCT, was calculated from the collapse profiles and the experimental values obtained for the FCC catalysts are reported in this paper. The fluidization quality of the fresh FCC catalysts improved with increasing temperature, as indicated by the increase in SCT values. On the other hand, the standardised collapse time of the E-cat FCC decreased with increasing temperature as the catalyst became less aeratable. Changes of the surface properties of this material occurred on increasing temperature. The flow behaviour of the E-cat catalyst was compared with fluidization of a Group C material. The aeratability of this latter material decreased exponentially, due to the dominant role of the interparticle forces over the hydrodynamic forces, with increasing temperature. The use of classical concepts such as the non bubbling ratio, u<sub>mb</sub>/u<sub>mf</sub>, to describe fluidization at low and high temperatures is discussed. Experimental u<sub>mb</sub>/u<sub>mf </sub>values obtained for the fresh FCC catalysts are compared with predictions.</p>

Effect of temperature and current manipulation on smolting in Chinook salmon (Oncorhynchus tshawytscha): the relationship between migratory behaviour and physiological development

2010 ◽  
Vol 67 (1) ◽  
pp. 191-201 ◽  
Author(s):  
Gregory E. Sykes ◽  
J. Mark Shrimpton
Keyword(s):  
Atpase Activity ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Effect Of Temperature ◽  
Strongly Correlated ◽  
Temperature Regimes ◽  
Experimental Treatments ◽  
Increasing Temperature ◽  
The Relationship

We investigated the role of temperature and current on migration pattern and physiological change in Chinook salmon ( Oncorhynchus tshawytscha ) smolts. Chinook parr were implanted with passive integrated transponder tags and placed in circular tanks with directional current. Paired antennas in each tank allowed for the monitoring of movements with or against the current. Two temperature regimes, naturally increasing (warm) and constant (cool), were combined with high current (>0.5 m·s–1) and low current (<0.1 m·s–1) to create four experimental treatments. At 2-week intervals, fish were sampled for gill Na+,K+-ATPase activity and plasma cortisol concentration. Increasing temperature resulted in an earlier peak in movement than colder groups and showed a distinct peak in gill Na+,K+-ATPase activity. Current did not influence physiological parameters associated with smolting and was not found to initiate movement; movement was related to accumulated thermal units (ATU). The presence of a strong, directional current, however, resulted in a period of more defined movement, suggesting a possible influence of current once migration is underway. A combination of either photoperiod or ATU with gill Na+,K+-ATPase was most strongly linked to movement. ATU was also found to be more strongly correlated with the smolting process than daily mean temperature.

Trace nanoanalysis

1994 ◽  
Vol 52 ◽  
pp. 940-941
Author(s):  
D. E. Newbury ◽  
R. D. Leapman
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Detection Efficiency ◽  
Volume Element ◽  
And Performance ◽  
Trace Constituents ◽  
Secondary Ion ◽  
Concentration Levels ◽  
Structure Properties

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).

The Relation Between Financial Incentives, Motivation, and Performance

2017 ◽  
Vol 16 (2) ◽  
pp. 61-76 ◽  
Author(s):  
Anaïs Thibault Landry ◽  
Marylène Gagné ◽  
Jacques Forest ◽  
Sylvie Guerrero ◽  
Michel Séguin ◽  
...  
Keyword(s):  
Financial Incentives ◽  
Work Performance ◽  
Autonomous Motivation ◽  
Compensation Plans ◽  
Work Settings ◽  
Path Analyses ◽  
Three Samples ◽  
And Performance ◽  
Performance Results

Abstract. To this day, researchers are debating the adequacy of using financial incentives to bolster performance in work settings. Our goal was to contribute to current understanding by considering the moderating role of distributive justice in the relation between financial incentives, motivation, and performance. Based on self-determination theory, we hypothesized that when bonuses are fairly distributed, using financial incentives makes employees feel more competent and autonomous, which in turn fosters greater autonomous motivation and lower controlled motivation, and better work performance. Results from path analyses in three samples supported our hypotheses, suggesting that the effect of financial incentives is contextual, and that compensation plans using financial incentives and bonuses can be effective when properly managed.

The role of copper ions in hydrogen peroxide bleaching: Their origin, removal, and effect on pulp quality

TAPPI Journal ◽  
2012 ◽  
Vol 11 (7) ◽  
pp. 37-46 ◽  
Author(s):  
PEDRO E.G. LOUREIRO ◽  
SANDRINE DUARTE ◽  
DMITRY V. EVTUGUIN ◽  
M. GRAÇA V.S. CARVALHO
Keyword(s):  
Hydrogen Peroxide ◽  
Copper Ions ◽  
Peroxide Bleaching ◽  
Metals Removal ◽  
Peroxide Decomposition ◽  
Equipment Corrosion ◽  
And Performance ◽  
And Control ◽  
Main Effects

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.

The Role of Research and Innovation in the Transformation of Agri-Food Systems

2018 ◽  
Vol 12 (2) ◽  
pp. 60-63
Author(s):  
Mariana Sandu ◽  
Stefan Mantea
Keyword(s):  
Technological Progress ◽  
Food Systems ◽  
Food System ◽  
Agricultural Research ◽  
Research And Innovation ◽  
And Performance ◽  
The Impact ◽  
Determinant Factor ◽  
Rapid Transformation

Abstract Agri-food systems include branching ramifications, which connect in the upstream the input suppliers with farmers, and downstream farmers, processors, retailers and consumers. In the last decades, at the level of the regions, food systems have undergone rapid transformation as a result of technological progress. The paper analyzes the changes made to the structure, behavior and performance of the agri-food system and the impact on farmers and consumers. Also, the role of agricultural research as a determinant factor of transformation of agri-food system is analyzed. The research objective is to develop technologies that cover the entire food chain (from farm to fork) and meet the specific requirements of consumers (from fork to farm) through scientific solutions in line with the principles of sustainable agriculture and ensuring the safety and food safety of the population.

Supervisi pendidikan

2020 ◽  
Author(s):  
nurul atika
Keyword(s):  
Public Relations ◽  
Educational Administration ◽  
Educational Goals ◽  
Literature Study ◽  
School Officials ◽  
Sourcing Strategies ◽  
Educational Supervision ◽  
Education Personnel ◽  
And Performance

Abstrak- In general, this study aims to determine and analyze the role of supervision in an education. This research uses the literature study method by collecting literature (material materials) sourced from books, journals, and other sources related to the science of Educational Administration. Supervision comes from the word super and vision, which means to see and review from above or view and assess from above, which is carried out by superiors on the activities, creativity and performance of subordinates. In terms of terms, in Carter's Good Dictionary Education, supervision is all the efforts of school officials in leading teachers and other education personnel to improve teaching. These include stimulating, selecting the growth and development of teachers' positions, selecting and revising educational goals, teaching materials and teaching methods, and evaluating teaching. Educational supervision has very important goals and benefits. The scope of educational supervision includes the following: Managerial supervision of the curriculum, Managerial supervision of student affairs, Managerial supervision of educators and education personnel, Managerial supervision of facilities and infrastructure, Managerial supervision of finance, Managerial supervision of public relations, Managerial supervision of administration, Administration supervision academics about learning, related to methods, sourcing strategies, and evaluations.

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