scholarly journals Wild Wheat Introgression Promotes Temporal Water fluxes Dynamics under Terminal Drought Stress through Plant-Atmospheric Interrelations

2021 ◽  
Author(s):  
Harel Bacher ◽  
Yoav Sharaby ◽  
Harkamal Walia ◽  
Zvi Peleg
Keyword(s):  
Water Stress ◽  
Structural Equation ◽  
Time Window ◽  
Genotypic Variation ◽  
Vapour Pressure Deficit ◽  
Introgression Line ◽  
Equation Model ◽  
Recurrent Parent ◽  
Terminal Drought ◽  
Water Influx

The intensity of water stress experienced by plants depends upon soil moisture status as well as atmospheric variables such as temperature, radiation, and air vapour pressure deficit (VPD). Although the role of shoot architecture with these edaphic and atmospheric factors is well-studied, the extent to shoot and root dynamic interactions as a continuum are controlled by genotypic variation is less known. Here, we targeted these interactions using a wild emmer introgression line (IL20) with a distinct drought-induced shift in the shoot-to-root ratio and its drought-sensitive recurrent parent Svevo. Using a gravimetric platform, we show that IL20 maintained higher root water influx and gas exchange under terminal drought, which supported a greater growth. Interestingly, the advantage of IL20 in root influx and transpiration was expressed earlier during the daily diurnal cycle under lower VPD and therefore supported higher transpiration efficiency. Application of structural equation model indicates that under water-stress, VPD and radiation are antagonistic to transpiration rate, whereas the root water influx operates as feedback for the higher atmospheric responsiveness of leaves. Collectively, these results suggest that a drought-induced shift in root-to-shoot ratio can improve plant water uptake potential in a short preferable time window determined by both water and atmospheric parameters.

Influence of phenology on grain yield variation among barley cultivars grown under terminal drought

1996 ◽  
Vol 47 (5) ◽  
pp. 757 ◽  
Author(s):  
JH Mitchell ◽  
S Fukai ◽  
M Cooper
Keyword(s):  
Water Stress ◽  
Grain Yield ◽  
Short Duration ◽  
Dry Matter ◽  
Genotypic Variation ◽  
Sowing Date ◽  
Barley Cultivars ◽  
Yield Variation ◽  
Terminal Drought ◽  
Long Duration

We investigated the influence of sowing time and genotypic variation for phenology on grain yield of barley in south-eastern Queensland. Over 3 seasons, 8 trials with 10 cultivars and 1 trial with 4 cultivars were conducted under either irrigated or terminal drought conditions at 2 locations. Rainout shelters ensured the development of severe terminal water stress. Trials were either sown on a common date, as conducted in traditional multi-environment trials, or over 3 weeks to synchronise anthesis among cultivars of different phenologies. Within the common sowing date trials, variation (P < 0.01) existed among cultivars for grain yield. From the 6 common sowing trials there was a negative correlation (P < 0.05) between grain yield and days to anthesis; that is, the shorter duration cultivars expressed the highest grain yield. Variation in days to anthesis accounted for 48-72% of the variation for grain yield. In the staggered sowing trials, where anthesis of all cultivars occurred within 4 or 2 days of the mean anthesis date, variation for grain yield was small or non-significant, and there was no association between grain yield and days to anthesis. The staggered sowing experiment with 10 cultivars indicated that duration of the vegetative phase was important in determining total dry matter production at maturity when cultivars were grown under terminal drought. Long-duration cultivars sown earlier had greater total dry matter at maturity than short-duration cultivars. This was associated with a greater water extraction by the long-duration cultivars, especially at depth, which remained inaccessible to later sown, short-duration cultivars. However, due to the low harvest index of the long-duration cultivars, grain yield of long- and short-duration cultivars was comparable when anthesis of cultivars was synchronised. When sown at the same time, a short-duration cultivar is advantageous because of a high chance of escaping water stress that develops during the critical development stage of anthesis. The results from the staggered sowing date experiments, however, indicated that the long-duration cultivars, when sown earlier in the season, had no yield disadvantage in comparison with the short-duration cultivars sown later in the season. Therefore, there is scope to develop barley cultivars of later phenology than is currently available to provide Queensland farmers with the option of utilising early rainfall events which are sometimes the only planting opportunity.

Idiographic Dynamics of Positive Affect in GAD

2020 ◽  
Vol 36 (3) ◽  
pp. 500-509
Author(s):  
Hannah G. Bosley ◽  
Devon B. Sandel ◽  
Aaron J. Fisher
Keyword(s):  
Positive Affect ◽  
Structural Equation ◽  
Alternative Hypothesis ◽  
Equation Model ◽  
Aggregated Data ◽  
Regulatory Strategy ◽  
Constant State ◽  
Automatic Search ◽  
Time Lagged ◽  
Exploratory Procedure

Abstract. Generalized anxiety disorder (GAD) is associated with worry and emotion regulation difficulties. The contrast-avoidance model suggests that individuals with GAD use worry to regulate emotion: by worrying, they maintain a constant state of negative affect (NA), avoiding a feared sudden shift into NA. We tested an extension of this model to positive affect (PA). During a week-long ecological momentary assessment (EMA) period, 96 undergraduates with a GAD analog provided four daily measurements of worry, dampening (i.e., PA suppression), and PA. We hypothesized a time-lagged mediation relationship in which higher worry predicts later dampening, and dampening predicts subsequently lower PA. A lag-2 structural equation model was fit to the group-aggregated data and to each individual time-series to test this hypothesis. Although worry and PA were negatively correlated in 87 participants, our model was not supported at the nomothetic level. However, idiographically, our model was well-fit for about a third (38.5%) of participants. We then used automatic search as an idiographic exploratory procedure to detect other time-lagged relationships between these constructs. While 46 individuals exhibited some cross-lagged relationships, no clear pattern emerged across participants. An alternative hypothesis about the speed of the relationship between variables is discussed using contemporaneous correlations of worry, dampening, and PA. Findings suggest heterogeneity in the function of worry as a regulatory strategy, and the importance of temporal scale for detection of time-lagged effects.

Differential Item Functioning in Brief Instruments of Disordered Eating

2019 ◽  
Vol 35 (6) ◽  
pp. 823-833 ◽  
Author(s):  
Desiree Thielemann ◽  
Felicitas Richter ◽  
Bernd Strauss ◽  
Elmar Braehler ◽  
Uwe Altmann ◽  
...  
Keyword(s):  
Differential Item Functioning ◽  
Disordered Eating ◽  
Structural Equation ◽  
Young Female ◽  
Eating Attitudes ◽  
Equation Model ◽  
German Population ◽  
Test Fairness ◽  
Item Functioning ◽  
Multiple Indicator

Abstract. Most instruments for the assessment of disordered eating were developed and validated in young female samples. However, they are often used in heterogeneous general population samples. Therefore, brief instruments of disordered eating should assess the severity of disordered eating equally well between individuals with different gender, age, body mass index (BMI), and socioeconomic status (SES). Differential item functioning (DIF) of two brief instruments of disordered eating (SCOFF, Eating Attitudes Test [EAT-8]) was modeled in a representative sample of the German population ( N = 2,527) using a multigroup item response theory (IRT) and a multiple-indicator multiple-cause (MIMIC) structural equation model (SEM) approach. No DIF by age was found in both questionnaires. Three items of the EAT-8 showed DIF across gender, indicating that females are more likely to agree than males, given the same severity of disordered eating. One item of the EAT-8 revealed slight DIF by BMI. DIF with respect to the SCOFF seemed to be negligible. Both questionnaires are equally fair across people with different age and SES. The DIF by gender that we found with respect to the EAT-8 as screening instrument may be also reflected in the use of different cutoff values for men and women. In general, both brief instruments assessing disordered eating revealed their strengths and limitations concerning test fairness for different groups.

The Influence of Cognitive and Affective Reactions to Feedback on Subsequent Goals

2010 ◽  
Vol 15 (2) ◽  
pp. 121-131 ◽  
Author(s):  
Remus Ilies ◽  
Timothy A. Judge ◽  
David T. Wagner
Keyword(s):  
Performance Feedback ◽  
Business School ◽  
Structural Equation ◽  
Emotional Reactions ◽  
Equation Model ◽  
Proposed Model ◽  
And Performance ◽  
Dispositional Measure ◽  
The Relationship ◽  
Reactions To Feedback

This paper focuses on explaining how individuals set goals on multiple performance episodes, in the context of performance feedback comparing their performance on each episode with their respective goal. The proposed model was tested through a longitudinal study of 493 university students’ actual goals and performance on business school exams. Results of a structural equation model supported the proposed conceptual model in which self-efficacy and emotional reactions to feedback mediate the relationship between feedback and subsequent goals. In addition, as expected, participants’ standing on a dispositional measure of behavioral inhibition influenced the strength of their emotional reactions to negative feedback.

Forced Zero Cross-Loading Misspecifications in Measurement Component of Structural Equation Models

Methodology ◽  
2014 ◽  
Vol 10 (4) ◽  
pp. 138-152 ◽  
Author(s):  
Hsien-Yuan Hsu ◽  
Susan Troncoso Skidmore ◽  
Yan Li ◽  
Bruce Thompson
Keyword(s):  
Structural Equation ◽  
Structural Model ◽  
Structural Equation Models ◽  
Equation Model ◽  
Model Fit ◽  
Model Specification ◽  
Simulation Design ◽  
Measurement Models ◽  
Fit Statistics ◽  
Path Coefficients

The purpose of the present paper was to evaluate the effect of constraining near-zero parameter cross-loadings to zero in the measurement component of a structural equation model. A Monte Carlo 3 × 5 × 2 simulation design was conducted (i.e., sample sizes of 200, 600, and 1,000; parameter cross-loadings of 0.07, 0.10, 0.13, 0.16, and 0.19 misspecified to be zero; and parameter path coefficients in the structural model of either 0.50 or 0.70). Results indicated that factor pattern coefficients and factor covariances were overestimated in measurement models when near-zero parameter cross-loadings constrained to zero were higher than 0.13 in the population. Moreover, the path coefficients between factors were misestimated when the near-zero parameter cross-loadings constrained to zero were noteworthy. Our results add to the literature detailing the importance of testing individual model specification decisions, and not simply evaluating omnibus model fit statistics.

Violence Exposure in Early Childhood: A Structural Equation Model

2007 ◽  
Author(s):  
Nathan D. Doty ◽  
Brian L. B. Willoughby ◽  
Betty S. Lai ◽  
Neena M. Malik
Keyword(s):  
Early Childhood ◽  
Structural Equation Model ◽  
Violence Exposure ◽  
Structural Equation ◽  
Equation Model

Memperkuat Loyalitas Melalui Kepercayaan, Kepuasan Dan Komitmen Studi Pada Nasabah PT. Bank Cimb Niaga

Liquidity ◽  
2018 ◽  
Vol 4 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Sri Widyastuti
Keyword(s):  
Customer Satisfaction ◽  
Relationship Quality ◽  
Structural Equation Model ◽  
Customer Loyalty ◽  
Structural Equation ◽  
Positive Influence ◽  
Equation Model ◽  
Survey Method ◽  
Branch Office

Customer loyalty is ‘suspected’not been able to optimizationrepetition of transactions, customer recommendation and durability with the establishment relationship quality of the trust, customer satisfaction and commitment. Therefore, research conducted on Bank CIMB Niaga aims to determine the extent of the trust, and commitment to customer satisfaction can increase X-tra and TabunganKU savings customer loyalty. This research is verification and the method of research is explanatory survey method, the sample is 160 customer X-tra and tabunganKU savings in the branch office Bank CIMB Niaga Bintaro. The analytical method used is structural equation model. The results showed loyalty can be achieved with relationship quality for customers through the establishment of trust, and commitment to customer satisfaction, which all three have a positive influence. Therefore, the management of Bank CIMB Niaga need to improve their ability in trust, satisfactionand commitmentwith the bank's customers to become increasingly favored customers.

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