Academic literature on the topic 'Mediation Analyses'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Mediation Analyses.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Mediation Analyses"
1
Ho, Jessie, and Paul L. Nesbit. "Personality and work outcomes: A moderated mediation model of self-leadership and gender." International Journal of Management Excellence 10, no. 2 (February 28, 2018): 1292–304. http://dx.doi.org/10.17722/ijme.v10i2.972.
Full textAbstract:
The purpose of this study is to examine the relationship between personality traits (conscientiousness and internal locus of control) and self-leadership. Specifically, we tested a moderated mediation model with self-leadership as the mediator between personality traits and job performance and job satisfaction and with gender as the moderator in influencing the mediations. Data were collected from a variety of organizations from 341 supervisor-subordinate dyads located in China and Hong Kong. Our analyses revealed that: (1) conscientiousness and internal locus of control were positively related to self-leadership in Chinese contexts; (2) self-leadership mediated the relationships of conscientiousness and internal locus of control with both job performance and job satisfaction; and (3) the mediating effects of self-leadership were not moderated by gender.
2
Solimun, Solimun, and Adji Achmad Rinaldo Fernandes. "Investigation the mediating variable: What is necessary? (case study in management research)." International Journal of Law and Management 59, no. 6 (November 13, 2017): 1059–67. http://dx.doi.org/10.1108/ijlma-09-2016-0077.
Full textAbstract:
Purpose This study aims to more deeply examine the various types of testing mediations and use the comparison test by using test-based mediation Sobel models and Bayesian approach. The purpose of this study are to apply the traditional (using indirect effect) and Sobel test, extend Yuan and MacKinnon (2009) work on Bayesian mediation analysis. Both analysis methods of mediation (Traditional, Sobel Test and Bayesian estimation) should apply in the research of management, by using structural equation modeling (SEM) in a structural model, with one mediation, one exogenous (independent) and one endogenous variable. The meta-analysis approximation has been used to investigate the job satisfaction as a mediation in the relationship between employee competence and performance (endogenous). Design/methodology/approach Data were collected from ten dissertations of students of the Management Doctoral Program at the Brawijaya University from 2009 until 2013; data were analyzed for the mediation variable of job satisfaction (M) in the relationship between employee competence (X) and employee performance (Y) (Muindi and Obonyo, 2015; Olcer, 2015; Sattar et al., 2015; Khan and Ahmed, 2015). A researcher can determine the mediating variable and whether it is complete or partial or if mediation exists in several ways. Findings The results of the above findings using meta-analysis showed that 60% of previous research states that job satisfaction is a partial mediation on relationship competence of the performance, 10% of previous research states that job satisfaction is a full mediation on relationship competence of the performance and 30% stated that job satisfaction is not pemediasi (pemediasi means Mediation variable) on the relationship between competence and performance. This research found that all three approaches provide similar conclusions for ten previous research. Research limitations/implications The findings showed that the Sobel approach and the Bayesian approach provide results that are more sensitive than the traditional approach. Practical implications In my opinion, the rule to investigate the mediation variable should be completed with the conditions (1) q (theta) is not statistically significant, (2) α (alpha) and β (beta) are significant, and (3) q’ (theta) is significant, and increase when M is include as an additional predictor. This condition called partial mediation. Social implications The traditional method is simpler and easy. The method is less sensitive and is not sufficient for investigating the mediating variables. In general, the method results in a mediation variable, but it cannot be used to determine either partial or complete mediation variables. So, investigation by Baron and Kenny Methods (in Hair et al., 2010), the rule or testing called Sobel Test and another approach such as Bayesian to determine the mediation variable is necessary. Originality/value Various methods for detecting mediating/intervening have been widely used in previous research as a method of measurement using indirect effect (Hair et al., 2010), and calculations have been performed using Sobel test (Baron and Kenny, 1986) and Bayesian approach (Enders, 2013). In this study, I wanted to more deeply examine the various types of testing mediations, and use the comparison test by using the test-based mediation Sobel models and Bayesian approach (Baron and Kenny, 1986; Enders, 2013). The statistical application should not be complicated and difficult, it but must rather be simple and easy, so that it is user-friendly. The traditional method is simpler and easier than the other methods, but how sensitive is it? This research is conducted to investigate this problem. The evaluation of mediating mechanisms has become a critical element of behavioral science research (Enders, 2013), especially in the field of management, not only to assess whether (and how) interventions achieve their effects but also, more, broadly, to understand the cause of behavioral change. Methodologists have developed mediation analysis techniques for a broad range of substantive applications. However, methods for estimating mediation mechanisms with various methods have been understudied. The purpose of this study is to apply the traditional (using indirect effect) and Sobel tests and extend Yuan and MacKinnon’s (2009) work on the Bayesian mediation analysis. Both analyses methods of mediation (traditional and Sobel test and Bayesian estimation) should apply in the research of management, by using structural equation modeling (SEM) in a structural model, with one mediation, one exogenous (independent) and one endogenous variable. The meta-analysis approximation has been used to investigate job satisfaction as the mediation in the relationship between employee competence and performance (endogenous). This study uses software R to complete the mediating effect (Enders, 2013). R is a language and environment for statistical computing and graphics. It is a GNU project which is similar to the S language and environment which was developed at Bell Laboratories (formerly AT&T, now Lucent Technologies) by John Chambers et al. R provides a wide variety of statistical analyses such as SEM and Mediation test. R provides an open source route for participation in that activity. The Bayesian estimation approach provides an R function and a macro that applies the method of mediation analysis.
3
Khan, Eijaz Ahmed, and Mohammed Quaddus. "Financial bootstrapping of informal micro-entrepreneurs in the financial environment." International Journal of Sociology and Social Policy 40, no. 11/12 (March 6, 2020): 1533–50. http://dx.doi.org/10.1108/ijssp-07-2019-0138.
Full textAbstract:
PurposeThis study first examines whether the capital structure served as a mediator between financing mix and firm performance. Furthermore, the authors investigate whether this mediation effect was moderated by the financial environment. Grounded in the pecking order theory (POT) and dynamic capability view (DCV), this study extends these concepts by configuring all links to a moderated mediation model.Design/methodology/approachThe study uses the structural equation modelling (SEM) approach and multiple regression analysis using “Hayes PROCESS macro” to empirically examine the model using data collected from 384 informal micro-firms operating in Bangladesh.FindingsIn the mediation analyses, results found that capital structure was a mediator in the link between financing mix and firm performance. In further moderated mediation analyses, outcomes confirmed that this mediation effect was moderated by the financial environment.Research limitations/implicationsThis investigation shows paths for future research including implications for theory advancement and intervention development.Originality/valueThis investigation offers the first step towards examining a moderated mediation effect, using POT and DCV, of the relationship between financial environment, financing mix, capital structure and firm performance.
4
Ovdiyenko, Ye B. "MEDIATION AGREEMENT AS A RESULT OF INDIVIDUAL REGULATION OF CIVIL LEGAL RELATIONS." Scientific Notes of V. I. Vernadsky Crimean Federal University. Juridical science 7 (73), no. 3 (2) (2022): 127–32. http://dx.doi.org/10.37279/2413-1733-2021-7-3(2)-127-132.
Full textAbstract:
The article presents the analysis concerning legislator’s position in respect of mediation; the author analyses principles underlying reconciliation of parties concluding mediation agreement; special attention is paid to the principle of confidentiality. The author considers mediation procedure as the type of individual regulation of civil legal relations. The analysis is conducted regarding preconditions advanced for figure of mediator in the light of current legislation, as well as with the view of the bill drafted by the Ministry of Justice of the Russian Federation. The author makes a conclusion that mediation agreement is the result of voluntary individual regulation of legal relations at issue.
5
Carter, Alice R., Eleanor Sanderson, Gemma Hammerton, Rebecca C. Richmond, George Davey Smith, Jon Heron, Amy E. Taylor, Neil M. Davies, and Laura D. Howe. "Mendelian randomisation for mediation analysis: current methods and challenges for implementation." European Journal of Epidemiology 36, no. 5 (May 2021): 465–78. http://dx.doi.org/10.1007/s10654-021-00757-1.
Full textAbstract:
AbstractMediation analysis seeks to explain the pathway(s) through which an exposure affects an outcome. Traditional, non-instrumental variable methods for mediation analysis experience a number of methodological difficulties, including bias due to confounding between an exposure, mediator and outcome and measurement error. Mendelian randomisation (MR) can be used to improve causal inference for mediation analysis. We describe two approaches that can be used for estimating mediation analysis with MR: multivariable MR (MVMR) and two-step MR. We outline the approaches and provide code to demonstrate how they can be used in mediation analysis. We review issues that can affect analyses, including confounding, measurement error, weak instrument bias, interactions between exposures and mediators and analysis of multiple mediators. Description of the methods is supplemented by simulated and real data examples. Although MR relies on large sample sizes and strong assumptions, such as having strong instruments and no horizontally pleiotropic pathways, our simulations demonstrate that these methods are unaffected by confounders of the exposure or mediator and the outcome and non-differential measurement error of the exposure or mediator. Both MVMR and two-step MR can be implemented in both individual-level MR and summary data MR. MR mediation methods require different assumptions to be made, compared with non-instrumental variable mediation methods. Where these assumptions are more plausible, MR can be used to improve causal inference in mediation analysis.
6
Fontanarosa, Phil B. "Reporting Findings From Mediation Analyses." JAMA 326, no. 11 (September 21, 2021): 1057. http://dx.doi.org/10.1001/jama.2021.15786.
Full text
7
Mattey-Mora, Paola, and Erick Nelson. "Sleep Disturbances, Obesity and Cognitive Function in Childhood: A Mediation Analysis." Current Developments in Nutrition 4, Supplement_2 (May 29, 2020): 1224. http://dx.doi.org/10.1093/cdn/nzaa057_040.
Full textAbstract:
Abstract Objectives Childhood cognitive development is influenced by biological and environmental factors. One such factor, obesity, impairs cognitive development and is associated with sleep disturbances (SDs). We examined the mediating role of SDs on the relationship between obesity and cognitive function in children from a large longitudinal study. Methods A total of 9951 children aged 9–11 years were included in this study. Children were recruited from 21 centers across the US from the Adolescent Brain Cognitive Development (ABCD) study. We assessed cognitive development using metrics for fluid (adaptation and new learning abilities), crystallized (experience-dependent abilities), and total cognitive function. Mediation analyses were conducted via linear regression modeling, with adjustment for potential confounders (sex, age, ethnicity, household income, parental education, and self-reported physical activity) for each of the 3 cognitive outcomes. Mediation significance was determined by bootstrapping. We also stratified our analyses by race (Caucasian, African-American, other racial minorities) to examine potential racial differences. Results We found a statistically significant inverse association between BMI and both total (β = −0.41, P < 0.001) and fluid (β = −0.49, P < 0.001) cognitive function. Stratified regression analyses found similar results for the Caucasians and other minorities groups, for both, fluid (Caucasian: β = −0.52, P < 0.001; other minorities β = −0.75, P = 0.01) and total cognitive function (Caucasian: β = −0.45, P < 0.001; other ethnicities: β = −0.76, P = 0.01). No association was observed among African Americans. Overall mediation analysis revealed that SDs were a partial mediator only for fluid cognitive function (P = 0.002). Further mediation analyses showed similar SDs partial mediation effects over fluid cognitive function in Caucasians (P = 0.002) and borderline significant mediation in the other minorities group (P = 0.06). Conclusions Our results suggest that SDs mediates the effect of obesity on cognitive functioning in children and that these effects vary across races, particularly as it pertains to fluid cognition. Fluid cognition is critical in childhood neurodevelopment, and further research is needed to address its long-term effects across the life course. Funding Sources None to declare.
8
Naeimijoo, Parastoo, Abbas Masjedi Arani, Maryam Bakhtiari, Gholamreza Mohammadi Farsani, and Ahmad Yousefi. "The Relationship Between Covid-related Psychological Distress and Perceived Stress With Emotional Eating in Iranian Adolescents: The Mediating Role of Emotion Dysregulation." Practice in Clinical Psychology 9, no. 4 (October 1, 2021): 329–38. http://dx.doi.org/10.32598/jpcp.9.4.803.1.
Full textAbstract:
Objective: The unprecedented nature of the COVID-19 pandemic and cessation of full face-to-face affiliation along with homebound restrictions have caused a variety of psychological distress among adolescents. Adolescents vary in the way they perceive such stressors and some respond with eating disturbances, which could reflect their dysfunctional emotion regulation strategies. The present research aimed at elucidating potential mediating pathways from perceived stress and psychological distress to emotional eating. Methods: This cross-sectional study was composed of 292 adolescents who were assessed using the Perceived Stress Scale, COVID-19-Related Psychological Stress Scale, Emotional Eating subscale of the Dutch Eating Behavior Questionnaire, and Difficulties in Emotion Regulation Scale. Correlation analyses were performed to assess the relationship between variables. ANOVA was conducted to detect differences between males and females for emotional eating. Then, a mediation analysis was conducted to assess whether emotional dysregulation was a mediator between psychological distress and emotional eating. Results: Results of path analyses indicated that a model with perceived stress and psychological distress predicting emotion eating through the mediation of emotion dysregulation was the best fit for the data (CFI=0.970, GFI=0.949, df=26, χ2=53.69, χ2/df=2.06, P>0.05, and RMSEA=0.069). Mediation analyses showed the mediating role of emotion dysregulation in the link between perceived stress and emotional eating (Sobel’s z=2.83, P<0.05) while, it could not function as a mediator between psychological distress and emotional eating (Sobel’s z=0.90, P>0.05). Conclusion: This study contributes to our understanding of the role of emotion regulation in the relationship between perceived stress and psychological distress and emotional eating in adolescents during the COVID-19 pandemic. The implication of this study is for therapeutic intervention to target emotional dysregulation of adolescents confronted with COVID-19 stressors.
9
Sieber, Stefan, Angélique Roquet, Charikleia Lampraki, and Daniela Jopp. "MULTIMORBIDITY AND QUALITY OF LIFE: EXAMINING THE PATHWAYS THROUGH LONELINESS, ADL, IADL, AND DEPRESSIVE SYMPTOMS." Innovation in Aging 6, Supplement_1 (November 1, 2022): 719–20. http://dx.doi.org/10.1093/geroni/igac059.2626.
Full textAbstract:
Abstract Background. Multimorbidity, defined as two or more chronic conditions, negatively affects quality of life. However, little is known about the underlying pathways leading from multimorbidity to lower quality of life (QoL). Objective. The objective of this paper was to examine multiple potential mediating factors (loneliness, Activities of Daily Living [ADL], Instrumental Activities of Daily Living [IADL], depressive symptoms) in the relationship between multimorbidity and quality of life. Furthermore, we explored moderated mediation patterns by age, gender, and education. Methods. Longitudinal data were drawn from five waves (from 2011 to 2020) of the Survey of Health, Ageing and Retirement in Europe (SHARE). We included 37,082 individuals aged 50 years and older in the analyses. The predictor (multimorbidity) and covariates were measured four and the mediators two years before the QoL outcome (CASP-12). Confounder-adjusted mediator and outcome models were fitted using mixed-effects models. The total association was decomposed into direct and indirect pathways applying causal mediation analyses with Monte-Carlo simulations. Results. Multimorbidity was associated with lower QoL four years later; 2.12%, 6.17%, and 19.90% of the association was mediated by ADL, IADL, and depressive symptoms, respectively. Mediation by loneliness was not significant. Generally, the mediation patterns were more pronounced in women and individuals with tertiary education as compared to primary and secondary. Differential mediation by age quartiles did not reveal a clear pattern. Conclusions. The results showed that depressive symptoms were the most important mediator between multimorbidity and QoL, with ADL and IADL also playing an important role.
10
Ruckteschler, Dorothee, and Anika Wendelstein. "Efficient Arb-Med-Arb Proceedings: Should the Arbitrator also be the Mediator?" Journal of International Arbitration 38, Issue 6 (November 1, 2021): 761–74. http://dx.doi.org/10.54648/joia2021035.
Full textAbstract:
The demand for hybrid proceedings combining elements of arbitration proceedings and mediation is growing continuously. The reason for this is the parties’ desire to make dispute resolution more efficient. A special type of hybrid proceedings are ‘arb-med-arb’ proceedings. These proceedings involve first initiating traditional arbitration proceedings. Before the taking of evidence begins, an attempt is then made to settle the dispute outside the arbitration proceedings in a separate mediation procedure. If the mediation fails, the arbitration proceedings are recommenced, and an arbitral award is issued. In the majority of arb-med-arb proceedings, a third party not involved in the arbitration proceedings is appointed as mediator. However, sometimes the parties ask the sole arbitrator or a member of the arbitral tribunal to act as mediator. This identity of the mediator and the (former and later) arbitrator raises many difficult questions, in particular, when the mediation fails. This article first analyses the pertinent most important regulations worldwide in arbitration and mediation laws, institutional arbitration, and mediation rules, and in soft law. Based on the results of this analysis, the authors develop some practical recommendations for the stakeholders in arb-med-arb proceedings. Arb-med-arb, Arbitrator, Mediator, Hybrid proceedings, Arbitration, Mediation, Same neutral, Declaration of consent, Ex parte communication, Caucusing
Dissertations / Theses on the topic "Mediation Analyses"
1
Kawamura, Morgan A. "Youth Prevention Programs: A Framework for Conducting Mediation Meta-Analyses." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7458.
Full textAbstract:
Often for prevention program designs, researchers are interested in understanding the processes through which a program impacts a targeted outcome. Mediation analysis assists in identifying not only how a program influences an outcome, but also which intermediate variables (i.e., mediators) cause the effects between a program and an outcome to occur. Mediation analysis explains why a program works, which is useful for program developers in creating effective prevention and intervention-based programs.
To make use of mediation analysis findings for preventive intervention programs, researchers need a comprehensive understanding of the mediators between various programs and outcomes. However, a comprehensive examination into which mediators are most effective has yet to take place. This is likely due to the lack of theoretical and quantitative guidance on conducting a comprehensive comparison study for mediated effects. As such, this work establishes a framework for measuring mediated effects in a comprehensive context. This thesis establishes a framework under which to evaluate mediated effects across multiple studies, demonstrates the application of this framework, and discusses the broader implications of this approach. Identifying the most effective mediators through the proposed approach lends a valuable understanding to practitioners and policymakers about critical actions for preventing a given outcome.
2
Chen, Chen. "Bayesian Analyses of Mediational Models for Survival Outcome." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1313684054.
Full text
3
Eshelman, Lee Renee. "The Impact of Substance Use on Women's Risk Perception and Risk for Sexual Revictimization: A Prospective Moderated-Mediation Analyses." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1399126729.
Full text
4
Chandran, Pillai Aiswarya Lekshmi Pillai. "Bisphenol-A and the Metabolic Syndrome: Analyses using the 2005-2010 adult NHANES data." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1339717737.
Full text
5
Li, Zhen. "Epidemiological Study of Diet, Obesity and Asthma in the French EGEA Study." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS087/document.
Full textAbstract:
L’objectif principal de la thèse était d’étudier les effets de l’alimentation et de l’obésité sur l’asthme et son évolution, en prenant en compte des facteurs de médiations spécifiques.La première partie de la thèse visait à étudier le rôle de l’alimentation dans l'asthme, en prenant en compte l’indice de masse corporelle (IMC) comme un médiateur potentiel, et en évaluant l’effet modificateur du tabac dans ces associations. Ce travail a d’abord porté sur le rôle de la consommation de charcuterie, récemment classée cancérogène. Parmi 971 adultes de l’étude des facteurs génétiques et environnementaux de l’asthme (EGEA), nous avons montré qu’une consommation élevée de charcuterie (au moins 4 fois par semaine) était associée de façon directe à l’aggravation des symptômes de l’asthme, et que seulement 14% de l’association entre la consommation de charcuterie et l’asthme était expliqué par l’IMC (effet indirect). Ce travail a ensuite porté sur le rôle de la qualité globale de l’alimentation, évaluée par le score alimentaire Alternate Healthy Eating Index 2010. Parmi 969 participants d’EGEA, nous avons montré qu’une alimentation de qualité était associée de façon directe à une amélioration des symptômes de l’asthme chez les non-fumeurs. L’effet indirect lié à l’IMC n’était pas significatif. La deuxième partie de la thèse visait à mieux comprendre l'association entre l'obésité et l'activité de l’asthme, en prenant en compte la leptine, une adipokine pro-inflammatoire, comme un médiateur potentiel. Parmi 331 adultes d’EGEA avec un asthme actif à l’inclusion, les analyses ont montré que différentes mesures élevées de la composition corporelle étaient associées à une activité persistante de l’asthme, avec un effet indirect très fort de la leptine dans ces associationsThe general aim of the thesis was to study the role of diet and obesity in asthma, while accounting for potential mediators in these analyses.The first part of the thesis aimed to investigate the role of dietary factors in asthma at a “macro-level”, considering body mass index (BMI) as a potential mediator, and to evaluate effect modification by smoking. We first focused on processed meat intake, a recent carcinogen. Among 971 participants from the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy (EGEA), analysis showed that high processed meat intake (at least 4 servings/week) was associated with worsening asthma symptoms over time, through a direct effect and to a lesser extent an effect mediated by BMI. We then focused on the overall diet quality assessed by the Alternate Healthy Eating Index 2010. Among 969 participants from the EGEA study, the analyses showed that a greater adherence to a better diet quality was associated with improved asthma symptoms over time in never smokers only and was not mediated through BMI. The second part of the thesis aimed to better understand the association between obesity and asthma at a “micro-level”, considering leptin, an inflammatory biological marker related to obesity, as a mediator. Including 331 participants from the EGEA study with current asthma at baseline, analysis showed that high body adiposity estimated by different measures was associated with persistent asthma activity, likely mediated by leptin
6
Janson, Emma. "Mediating with God : Quantitative Analysis on Mediation and Religiosity - What effect does severity of conflict have on mediation onset in religious conflicts?" Thesis, Uppsala universitet, Institutionen för freds- och konfliktforskning, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-373136.
Full textAbstract:
The number of conflicts with religious dimensions has been steadily increasing over the last few decades. Previous research has found that religious conflicts are less likely to end by mediation whilst little research has been done as to what makes them initiate mediation. Building upon Ripeness Theory, this paper argues that the religious component makes religious parties less sensitive towards mutually hurting stalemates, but not immune to them, due to their heterogenous nature. This proposition is analysed by examining the empirical pattern of mediation onset in conflicts over religious incompatibilities using a logistic regression analysis. The findings suggest that higher numbers of average battle-related deaths, together with the duration of conflict and presence of crude oil reserves, increase the likelihood of mediation onset, whilst differentiations in centrality of a religious goal or religious identity divides have no statistically significant effect.
7
Bocquier, Aurélie. "Contribution à la compréhension des liens entre statut socio-économique et comportements de santé." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0713.
Full textAbstract:
Cette thèse visait à contribuer aux connaissances sur les différenciations sociales des comportements de santé en France et à une meilleure compréhension des mécanismes sous-jacents à ces différenciations. Nous nous sommes plus particulièrement intéressés au rôle de certains facteurs sociocognitifs (perceptions, croyances…) inspirés de théories issues de la sociologie du risque et de la déviance. En utilisant les données des enquêtes Baromètre cancer 2010 et Baromètre santé 2016, nos travaux ont porté sur des comportements relatifs à la prévention primaire de certains cancers (consommation d’alcool et protection solaire) et des maladies infectieuses (vaccinations infantiles). Un faible statut socio-économique était associé à une relativisation accrue du risque de cancer lié à la consommation d’alcool et à des connaissances et croyances vis-à-vis du risque solaire plus éloignées du « savoir expert ». Ces derniers facteurs expliquaient en partie la moindre utilisation des moyens de protection solaire chez les personnes ayant un faible statut socio-économique. Dans le domaine de la vaccination, nous avons constaté une prévalence plus élevée de l’hésitation vaccinale chez les parents ayant un niveau de diplôme supérieur ou égal au baccalauréat. Cette association s’expliquait en partie par le fait que les parents diplômés avaient un moindre niveau de confiance dans les autorités et la médecine conventionnelle et un degré d’implication dans les décisions de santé accru. Ces résultats fournissent des pistes pour conduire des actions de promotion de la santé tenant compte du contexte social dans lequel sont inscrits les comportements des individus, plus efficaces et équitablesThis thesis aimed to contribute to current scientific knowledge about the social differentiation of health behaviours in France and to a better understanding of the mechanisms underlying this differentiation. We focused on the role of specific sociocognitive factors (perceptions and beliefs) based on theories derived from the sociology of risk and the sociology of deviance. This work used data from the 2010 Baromètre cancer survey and the 2016 Baromètre santé survey to examine health behaviours related to primary prevention of some cancers (alcohol consumption and sun protection) and infectious diseases (childhood vaccinations). People of low socioeconomic status were more prone to relativize the alcohol-related risks of cancer and to have substantially less knowledge about sun health and more “false beliefs” about sun protection than people of high socioeconomic status. This knowledge and these false beliefs were significant mediators of the positive association between socioeconomic status and sun-protection behaviours. In the field of vaccination, we found a higher prevalence of vaccine hesitancy among parents who had at least passed the “bac”. This association was partly explained by their lower level of trust in health authorities and mainstream medicine than among the least educated group and by their greater commitment to making “good” health-related decisions. From a public health perspective, these results furnish avenues for designing health promotion interventions that take into account the social context in which people’s health behaviours are embedded to improve both effectiveness and equity
8
Wang, Wei. "CAUSAL MEDIATION ANALYSIS FOR NON-LINEAR MODELS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1332961697.
Full text
9
Hill, Chris. "A pragmatic analysis of family mediation." Thesis, Bangor University, 2007. https://research.bangor.ac.uk/portal/en/theses/a-pragmatic-analysis-of-family-mediation(c7c254b4-b9f8-4c94-8f98-9a2f5e0fd9e5).html.
Full textAbstract:
Family (or divorce) mediation aims to assist couples who are separating or divorcing to come to agreed arrangements regarding children, property and finances. In the UK it is a service which is offered as an alternative to litigation and is not, at this stage, compulsory. Family mediation is an interactional setting which combines elements of both formality and informality: in theory mediators control the process of the encounter, whilst clients control the outcome. Mediators are also charged with conducting themselves in a manner which is neutral as to outcome, and impartial as to process. In reality, of course, the language behaviours of both practitioners and clients are not so clearly delineated. This research is based upon audio recordings of mediation sessions in the North Wales Service and takes an interactional pragmatic approach. The primary analytic `tools' are the concepts of complex illocutionary acts and discourse roles as developed by Thomas (1995,2004,2006 and forthcoming). A number of topics are considered, in particular the verbal enactment of mediator impartiality and neutrality, and of power and politeness by both clients and practitioners.
10
Valeri, Linda. "Statistical Methods for Causal Mediation Analysis." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10690.
Full textAbstract:
Mediation analysis is a popular approach in the social an biomedical sciences to examine the extent to which the effect of an exposure on an outcome is through an intermediate variable (mediator) and the extent to which the effect is direct. We first develop statistical methods and software for the estimation of direct and indirect causal effects in generalized linear models when exposure-mediator interaction may be present. We then study the bias of direct and indirect effects estimators that arise in this context when a continuous mediator is measured with error or a binary mediator is misclassified. We develop methods of correction for measurement error and misclassification coupled with sensitivity analyses for which no auxiliary information on the mediator measured with error is needed. The proposed methods are applied to a lung cancer study to evaluate the effect of genetic variants mediated through smoking on lung cancer risk and to a perinatal epidemiological study on the determinants of preterm birth.
Books on the topic "Mediation Analyses"
1
Iacobucci, Dawn. Mediation analysis. Los Angeles: Sage, 2008.
Find full text
2
Iacobucci, Dawn. Mediation analysis. Los Angeles: Sage, 2008.
Find full text
3
Iacobucci, Dawn. Mediation Analysis. 2455 Teller Road, Thousand Oaks California 91320 United States of America: SAGE Publications, Inc., 2008. http://dx.doi.org/10.4135/9781412984966.
Full text
4
M, Maxwell Madeline, ed. Storied conflict talk: Narrative construction in mediation. Amsterdam: John Benjamins Pub. Co., 2010.
Find full text
5
Stewart, Katherine A. Storied conflict talk: Narrative construction in mediation. Amsterdam: John Benjamins Pub. Co., 2010.
Find full text
6
Jabri, Vivienne. Discourses on violence: Conflict analysis reconsidered. Manchester: Manchester University Press, 1996.
Find full text
7
1954-, Monk Gerald, ed. Practicing narrative mediation: Loosening the grip of conflict. San Francisco: Jossey-Bass, 2008.
Find full text
8
Spindler, Gerald. Gerichtsnahe Mediation in Niedersachsen: Eine juristisch- rechtsökonomische Analyse. Göttingen: Universitätsverlag Göttingen, 2006.
Find full text
9
John, Winslade, ed. When stories clash: Addressing conflict with narrative mediation. Chagrin Falls, Ohio: Taos Institute Publications, 2013.
Find full text
10
Shailor, Jonathan G. Empowerment in dispute mediation: A critical analysis of communication. Westport, Conn: Praeger, 1994.
Find full textBook chapters on the topic "Mediation Analyses"
1
Hair, Joseph F., G. Tomas M. Hult, Christian M. Ringle, Marko Sarstedt, Nicholas P. Danks, and Soumya Ray. "Mediation Analysis." In Classroom Companion: Business, 139–53. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-80519-7_7.
Full textAbstract:
AbstractMediation occurs when a third variable, referred to as a mediator construct, intervenes between two other directly related constructs. More precisely, a change in the exogenous construct results in a change of the mediator construct, which in turn changes the endogenous construct. The mediator analysis evaluates the factors related to the cause–effect relationship between an exogenous construct and an endogenous construct. In the simplest form, the analysis considers only one mediator construct, but the path model can also include multiple mediating constructs simultaneously, as well as moderated mediation. We illustrate mediation analysis in PLS-SEM by using the SEMinR package and the corporate reputation model as an example.
2
Fairchild, Amanda J., and David P. MacKinnon. "Using Mediation and Moderation Analyses to Enhance Prevention Research." In Defining Prevention Science, 537–55. Boston, MA: Springer US, 2014. http://dx.doi.org/10.1007/978-1-4899-7424-2_23.
Full text
3
Zhang, Haixiang, Lifang Hou, and Lei Liu. "A Review of High-Dimensional Mediation Analyses in DNA Methylation Studies." In Methods in Molecular Biology, 123–35. New York, NY: Springer US, 2021. http://dx.doi.org/10.1007/978-1-0716-1994-0_10.
Full text
4
Carrión, Gabriel Cepeda, Christian Nitzl, and José L. Roldán. "Mediation Analyses in Partial Least Squares Structural Equation Modeling: Guidelines and Empirical Examples." In Partial Least Squares Path Modeling, 173–95. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-64069-3_8.
Full text
5
Lubor, Kysučan. "Classical Tradition in Czech Renaissance and Baroque Literature." In Biblioteca di Studi Slavistici, 97–116. Florence: Firenze University Press, 2020. http://dx.doi.org/10.36253/978-88-5518-198-3.06.
Full textAbstract:
The study deals with the influence of the classical tradition on Czech literature of the Early Modern Period (Renaissance, Baroque). The article demonstrates this influence through examples of the use of selected motifs from ancient history in all of the main genres of the literature of that era: homily, legend, school drama, poetry and educational literature. The study also analyses the educational background of the authors and readers of the era and their attitude to ancient history; the ways of mediation and making use of ancient motifs in the literature; and the influence of ancient historiography on Renaissance and Baroque culture and interpretation of history.
6
Huber, Martin. "Mediation Analysis." In Handbook of Labor, Human Resources and Population Economics, 1–38. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-57365-6_162-1.
Full text
7
Huber, Martin. "Mediation Analysis." In Handbook of Labor, Human Resources and Population Economics, 1–38. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-57365-6_162-2.
Full text
8
Tofighi, Davood. "Mediation Analysis." In Encyclopedia of Quality of Life and Well-Being Research, 3963–66. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-007-0753-5_1771.
Full text
9
Steen, Johan, and Stijn Vansteelandt. "Mediation Analysis." In Handbook of Graphical Models, 405–38. Boca Raton, Florida : CRC Press, c2019.: CRC Press, 2018. http://dx.doi.org/10.1201/9780429463976-17.
Full text
10
Nitzl, Christian, José L. Roldán, and Gabriel Cepeda. "Mediation Analyses in Partial Least Squares Structural Equation Modeling, Helping Researchers Discuss More Sophisticated Models: An Abstract." In Marketing at the Confluence between Entertainment and Analytics, 693. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-47331-4_130.
Full textConference papers on the topic "Mediation Analyses"
1
Gheno, Gloria. "A NEW SEMIPARAMETRIC APPROACH FOR MEDIATION ANALYSES." In 30th International Academic Conference, Venice. International Institute of Social and Economic Sciences, 2017. http://dx.doi.org/10.20472/iac.2017.030.015.
Full text
2
Jin, Kuan-Yu. "Influences of Carryover Effects Across Scales on Mediation Analyses." In 2022 AERA Annual Meeting. Washington DC: AERA, 2022. http://dx.doi.org/10.3102/1883436.
Full text
3
Bal, Harun, Mehmet Demiral, and Emrah Eray Akça. "Mediating Effect of the Governance Indicators in the Relationship between Natural Resources Abundance and Economic Growth: Empirical Evidence from the." In International Conference on Eurasian Economies. Eurasian Economists Association, 2014. http://dx.doi.org/10.36880/c05.00950.
Full textAbstract:
This study purposes to identify the relationship between gross domestic product (GDP) and natural resources abundance, focusing on the mediator roles of governance indicators for selected 21 MENA and Caspian countries. Governance indicators used in the study are World Bank’s six global governance indicators. Annual panel data for the period of 1996-2012 are used. In this context, the study estimates the impact of crude oil production per capita (independent variable) on GDP per capita (dependent variable) at first, and then hierarchical panel regression analyses are conducted to determine the mediator variable roles of the governance indicators in this relationship. Sobel test is also applied to confirm whether the mediation effect is significant. Results from the pairwise panel regression analyses reveal that crude oil production per capita is negatively associated with all worldwide governance indicators, mostly with control of corruption, voice and accountability and regulatory quality. The progressive improvements of all dimensions of governance indicators, especially control of corruption, rule of law and government effectiveness, seem to promote GDP per capita. Results from the hierarchical regression analysis demonstrate that governance indicators play an important role as a partial mediator in the relationships crude oil production and GDP per capita. This evidence supports that weak governance indicators tend to hinder natural resources abundance to contribute economic growth. Overall findings highlight the increasing importance of policies intending to reduce corruption and violence, together with stimulating legitimacy, transparency and institutional quality for the countries investigated.
4
Portere, Viktorija, and Baiba Briede. "The Meaning of Constructivist Approach in Mediation and the Role of the Mediator." In 14th International Scientific Conference "Rural Environment. Education. Personality. (REEP)". Latvia University of Life Sciences and Technologies. Faculty of Engineering. Institute of Education and Home Economics, 2021. http://dx.doi.org/10.22616/reep.2021.14.032.
Full textAbstract:
The process of overcoming a conflict in mediation using constructivist ideas is revealed in the study. A mediator’s roles in the frame of the constructivist approach represent the topicality of the study. The mediator’s role is analysed and the emphasis is on the constructivist frame. The mediator’s pedagogical role is in the centre of the study. In the process of the study, the aim was to find out theoretical explanations of the meaning of the constructivist approach in mediation, how it occurs and what is the role of mediator in the mediation process based on dialogue? The methodology of the study comprises a theoretical assessment of the role of the mediator based on a constructivist approach with a purposeful emphasis on a dialogue between parties. The mediator facilitates a dialogical mediation process being also a pedagogue who helps the parties to learn how to keep a dialogue. Analysis of the mediator’s role and the usage of D.A. Kolb’s learning types in the stages of mediation are the main results of the study. The significance of the study implies a substantiation of various roles of the mediator, constructivist approach with the emphasis on the dialogue and implementation of D.A. Kolb’s learning types in the stages of mediation.
5
Apostu, Milka Nicoleta, Octav Sorin Candel, and Maria Nicoleta Turliuc. "Three Cords Twisted Together. The Investment Model, Religiousness and Forgiveness." In World Lumen Congress 2021, May 26-30, 2021, Iasi, Romania. LUMEN Publishing House, 2022. http://dx.doi.org/10.18662/wlc2021/04.
Full textAbstract:
The main purpose of the present research is to explore the influence of religiousness on couple commitment, drawing from previous studies where religiousness was confirmed as a strong predictor for positive relationship outcomes. We also aim to analyze relationship satisfaction as a mediating variable between religiousness and commitment. Furthermore, the study seeks to investigate forgiveness in dyadic romantic relationships, testing its role as a moderator of the association between relationship satisfaction and commitment. The procedure includes the recruitment of heterosexual students enrolled in post-graduate courses and their partners to take part in the present study. The final sample consists of 116 individuals involved in romantic relationships. All participants filled in a series of validated self-reported measures, providing data which was analyzed using parametric statistical tests. Additionally, we conducted mediation and moderation analyses. Results indicate that relationship satisfaction is positively associated with commitment, whereas religiousness is positively associated with relationship satisfaction, thus having an indirect effect on commitment. Additionally, considering overall forgiveness as well as the negative vs. positive components of the construct, we find that positive forgiveness is associated with commitment, when satisfaction is also considered in the equation. The current results have important therapeutic implications, such as using forgiveness-related therapies for couples and enhancing relationship satisfaction as means to consolidate relationship commitment.
6
Tang, Karen, Elijah Otis, Alexandra Loverock, Cameron Wild, and Igor Yakovenko. "The Role of Motives in Understanding the Link Between Personality and Cannabis Misuse." In 2020 Virtual Scientific Meeting of the Research Society on Marijuana. Research Society on Marijuana, 2021. http://dx.doi.org/10.26828/cannabis.2021.01.000.19.
Full textAbstract:
Background and aim: A robust association exists between substance use and personality, with personality risk factors representing phenotypes of vulnerability to substance misuse. As such, personality risk factors may be valuable constructs for understanding specific motivations for substance misuse. Given the loosening of restrictions on cannabis worldwide, research focusing on understanding cannabis use in young adults, a particularly at-risk population, remains a vital area of research. The existing data provides extensive support for the mediating role of coping motives on personality risk factors and problematic cannabis use; however, the role of other types of motives has remained largely unexplored. Our study examined the mediating role of cannabis use motives between personality and cannabis misuse among university students. We also explored the predictive value of personality phenotypes for cannabis use problems. Research question and hypothesis: Do motivations for cannabis use mediate or explain the relationship between personality type and cannabis use problem severity? Hypothesis 1: sensation-seeking (SS) and impulsivity (IMP), but not anxiety sensitivity and hopelessness, will be associated with greater cannabis use problem severity. Hypothesis 2: motives for use (i.e., coping, conformity, social, enhancement, expansion) will mediate the association between personality risk and cannabis use problem severity. Method: A survey was administered to 1073 undergraduate students. We examined whether motivations for use (mediator variable) explained the relationship between personality (predictor variable) and cannabis use disorder severity (outcome variable) using an ordinary least-squares (OLS) based mediation analysis. Results: As hypothesized, SS and IMP predicted greater cannabis use problems. A noteworthy finding was that conformity motives were a significant mediator between SS and IMP and cannabis use, whereby higher levels of SS/IMP led to greater endorsement of conformity motives, which in turn led to lower cannabis misuse. Enhancement motives were also a significant mediator between IMP and cannabis use. Expansion motives were a significant mediator between SS and cannabis use. Conclusion: Understanding reasons for use (i.e., motives) allows us to identify those at greatest risk for cannabis misuse. Findings from this study may help explain the underlying mechanisms by which personality risk factors lead to cannabis use disorder in young adults. A greater understanding of these personality phenotypes may have implications for the development of personality-specific interventions for cannabis use.
7
Portere, Viktorija, and Vladimirs Morevs. "Dialogue is a sign of constructiveness in mediation." In Research for Rural Development 2020. Latvia University of Life Sciences and Technologies, 2020. http://dx.doi.org/10.22616/rrd.26.2020.043.
Full textAbstract:
Dialogue (discourse) is the main indication leading us to the conclusion that mediation is constructive. Discourse, the main form of dialogue, allows to achieve a positive result of mediation – an agreement between the participants of the conflict, as well as to learn dialogue communication skills. The aim of this study is to determine the types of dialogue used in mediation, the usage of recognized dialogue, and to find methods for assessing the dialogue (discourse) skills that need to be taught to the participants of the conflict, as well as future mediators and to evaluate the effectiveness of mediation. The research was conducted based on the theoretical methods of analysis of modern concept of dialogue and empirical testing methods (using questionnaires) of the participants of the conflicts and future mediators. Methods of mathematical statistics were used, when processing and analyzing the results of the questionnaires. As a result of this work, the types of dialogue used in mediation are identified, recommendations on the choice of components and barriers of dialogue to be considered by the mediator when training participants in the conflict and future mediators are made, as well as recommendations on assessment the effectiveness of mediation are offered.
8
Stanković, Gordana, and Marijana Dukić Mijatović. "POSREDNIČKE USLUGE JAVNIH IZVRŠITELjA." In XVII majsko savetovanje. Pravni fakultet Univerziteta u Kragujvcu, 2021. http://dx.doi.org/10.46793/uvp21.377s.
Full textAbstract:
The amended provisions of the Law on Enforcement and Security (2015) from 2019 envisage a new, intermediary function of public executors before initiating the enforcement procedure by regulating the mediation procedure for the purpose of voluntary settlement of the monetary claim of the executive creditor. In addition to the mediating role that the public executor may have during the enforcement procedure, provided for in the original text of the Law on Enforcement and Security, its mediating function has been extended to the mediation procedure that can be conducted before the enforcement procedure is initiated to settle the claim. In this way, the range of judicial services provided by public bailiffs as special judicial bodies has been expanded. The paper presents and critically analyzes the provisions of the Law on Enforcement and Security which regulate this new intermediary service that can be provided by public bailiffs, which is intended to relieve to some extent both courts and public bailiffs in the enforcement procedure, speed up the settlement of enforcement creditors. and reduce the costs of enforcement proceedings. The authors point out some of the implications that may arise in connection with this procedure.
9
Domingues, Felipe, Salvatore Zingale, and Dijon De Moraes. "The pragmaticism as a route to designing: Understanding the inferential logics of sense attribution." In Systems & Design: Beyond Processes and Thinking. Valencia: Universitat Politècnica València, 2016. http://dx.doi.org/10.4995/ifdp.2016.3214.
Full textAbstract:
The objective of this paper is to discuss the inferential logics of sense attribution to everyday objects. The arguments presented take part of a broader investigation that aims at evolving a full methodological research framework. Such framework intends to explore the possibility of development of a method of systematic analysis of the relationship established between users and objects in their context of use and specific circumstances.The starting point of the discussion is the pragmatistic maxim: “Consider what effects, that might conceivably have practical bearing, we conceive the object of our conception to have. Then, our conception of these effects is the whole of our conception of the object” (Peirce, CP 4.402). Both terms, effects and practical bearing, associated with the concept of sense, were of great importance to support the evolvement of the theoretical discourse developed in the paper. In addiction, the concept of sense adopted is also rooted in Peirce’s essays: “Our idea of anything is our idea of its sensible effects” (Peirce, CP 5.401). According to Peirce, the senses of any sign (e.g., objects) are associated with all possible effects and the practical consequences that they produce or could produce (Zingale & Domingues, 2015). Thus, considering that signs can be also understood as processes of mental mediation, the practical bearings urged by sensible effects are direct linked to inferential logic mechanisms (induction, deduction, abduction) in the processes of sense attribution. Then, how to analyze intangible aspects such interpretative answers and practical consequences in the context of use and specific circumstances?The statements contained in the paper may contribute to the fields of design (practical) and semiotics and design (theoretical) in terms of providing a theoretical model. Such model intends to increase the scientific understanding of the logical mediation processes involved in artifacts fruition, which is believed to have effects on the practical processes of analysis and development of goods; and may also add knowledge to the discussions and contributions postulated by Deni (2015) and Boztepe (2007).Concluding, this contribution may bring into the field of design discussions on the comprehension of the relationship between users and their goods, introducing a purpose of a framing method of the logic of the pragmatistic dimension of artifacts. In further stages of the so-called broader investigation, the evolvement of such method aims at aiding the analyses and introduction of symbolic features into artifacts in the very early stages of design.DOI: http://dx.doi.org/10.4995/IFDP.2016.3214
10
Zinovieva, Darina. "MEDIATION AND MEDIATORS IN THE HEALTHCARE." In THE MEDIATION IN THE DIFFERENT PUBLIC SPHERES 2021. University publishing house "Science and Economics", University of Economics - Varna, 2021. http://dx.doi.org/10.36997/mdps2021.24.
Full textAbstract:
It is considered how mediation is regulated as an out-of-court way of agreement between two disputing parties in the healthcare system. For this purpose, an analysis of the current general and special laws, according to which such an agreement can be implemented, has been made. Practical issues related to problems in the implementation of the agreement are also presented, in view of the specifics of the disputes in the healthcare sector. The new legal figure of a "health mediator" is analyzed, the rights and obligations that are normatively regulated, the benefits and the needs for optimization of the regulation. The results of the analysis are summarized and specific conclusions "de lege ferenda" are proposed.
Reports on the topic "Mediation Analyses"
1
Heckman, James, and Rodrigo Pinto. Econometric Mediation Analyses: Identifying the Sources of Treatment Effects from Experimentally Estimated Production Technologies with Unmeasured and Mismeasured Inputs. Cambridge, MA: National Bureau of Economic Research, August 2013. http://dx.doi.org/10.3386/w19314.
Full text
2
Heckert, Jessica, Jessica Leight, Josué Awonon, and Aulo Gelli. Understanding the role of different program components of a nutrition sensitive intervention in mediating impact: Applying causal mediation analysis to experimental evidence from Burkina Faso. Washington, DC: International Food Policy Research Institute, 2021. http://dx.doi.org/10.2499/p15738coll2.134866.
Full text
3
Al Saleh, Abdullah. Conflict Analysis: Exploring the Role of Kuwait in Mediation in the Middle East. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.3199.
Full text
4
Frölich, Markus, and Martin Huber. Direct and indirect treatment effects: causal chains and mediation analysis with instrumental variables. Cemmap, July 2014. http://dx.doi.org/10.1920/wp.cem.2014.3114.
Full text
5
Bijlsma, Maarten J., and Ben Wilson. Modelling the socio-economic determinants of fertility: a mediation analysis using the parametric g-formula. Rostock: Max Planck Institute for Demographic Research, May 2017. http://dx.doi.org/10.4054/mpidr-wp-2017-013.
Full text
6
Fromm, Hillel, Paul Michael Hasegawa, and Aaron Fait. Calcium-regulated Transcription Factors Mediating Carbon Metabolism in Response to Drought. United States Department of Agriculture, June 2013. http://dx.doi.org/10.32747/2013.7699847.bard.
Full textAbstract:
Original objectives: The long-term goal of the proposed research is to elucidate the transcription factors, genes and metabolic networks involved in carbon metabolism and partitioning in response to water deficit. The proposed research focuses on the GTLcalcium/calmodulinbindingTFs and the gene and metabolic networks modulated by these TFs in Arabidopsis thaliana. The specific objectives are as follows. Objective-1 (USA): Physiological analyses of GTL1 loss- and gain-of-function plants under water sufficient and drought stress conditions Objective 2 (USA / Israel-TAU): Characterizion of GTL target genes and bioinformatic analysis of data to eulcidate gene-network topology. Objective-3 (Israel-TAU): Regulation of GTLmediated transcription by Ca²⁺/calmodulin: mechanism and biological significance. Objective-4 (Israel-BGU): Metabolic networks and carbon partitioning in response to drought. Additional direction: In the course of the project we added another direction, which was reported in the 2nd annual report, to elucidate genes controlling drought avoidance. The TAU team has isolated a few unhydrotropic (hyd) mutants and are in the process of mapping these mutations (of hyd13 and hyd15; see last year's report for a description of these mutants under salt stress) in the Arabidopsis genome by map-based cloning and deep sequencing. For this purpose, each hyd mutant was crossed with a wild type plant of the Landsberg ecotype, and at the F2 stage, 500-700 seedlings showing the unhydrotropic phenotype were collected separately and pooled DNA samples were subkected to the Illumina deep sequencing technology. Bioinformatics were used to identify the exact genomic positions of the mutations (based on a comparison of the genomic sequences of the two Arabidopsis thaliana ecotypes (Columbia and Landsberg). Background: To feed the 9 billion people or more, expected to live on Earth by the mid 21st century, the production of high-quality food must increase substantially. Based on a 2009 Declaration of the World Summit on Food Security, a target of 70% more global food production by the year 2050 was marked, an unprecedented food-production growth rate. Importantly, due to the larger areas of low-yielding land globally, low-yielding environments offer the greatest opportunity for substantial increases in global food production. Nowadays, 70% of the global available water is used by agriculture, and 40% of the world food is produced from irrigated soils. Therefore, much needs to be done towards improving the efficiency of water use by plants, accompanied by increased crop yield production under water-limiting conditions. Major conclusions, solutions and achievements: We established that AtGTL1 (Arabidopsis thaliana GT-2 LIKE1) is a focal determinant in water deficit (drought) signaling and tolerance, and water use efficiency (WUE). The GTL1 transcription factor is an upstream regulator of stomatal development as a transrepressor of AtSDD1, which encodes a subtilisin protease that activates a MAP kinase pathway that negatively regulates stomatal lineage and density. GTL1 binds to the core GT3 cis-element in the SDD1 promoter and transrepresses its expression under water-sufficient conditions. GTL1 loss-of-function mutants have reduced stomatal number and transpiration, and enhanced drought tolerance and WUE. In this case, higher WUE under water sufficient conditions occurs without reduction in absolute biomass accumulation or carbon assimilation, indicating that gtl1-mediated effects on stomatal conductance and transpiration do not substantially affect CO₂ uptake. These results are proof-of-concept that fine-tuned regulation of stomatal density can result in drought tolerance and higher WUE with maintenance of yield stability. Implications: Accomplishments during the IS-4243-09R project provide unique tools for continued discovery research to enhance plant drought tolerance and WUE.
7
Philosoph-Hadas, Sonia, Peter Kaufman, Shimon Meir, and Abraham Halevy. Signal Transduction Pathway of Hormonal Action in Control and Regulation of the Gravitropic Response of Cut Flowering Stems during Storage and Transport. United States Department of Agriculture, October 1999. http://dx.doi.org/10.32747/1999.7695838.bard.
Full textAbstract:
Original objectives: The basic goal of the present project was to increase our understanding of the cellular mechanisms operating during the gravitropic response of cut flowers, for solving their bending problem without affecting flower quality. Thus, several elements operating at the 3 levels o the gravity-induced signal transduction pathway, were proposed to be examined in snapdragon stems according to the following research goals: 1) Signaling: characterize the signal transduction pathway leading to the gravitropic response, regarding the involvement of [Ca2+]cyt as a mediator of IAA movement and sensitivity to auxin. 2) Transduction by plant hormones: a) Examine the involvement of auxin in the gravitropic response of flower stems with regard to: possible participation of auxin binding protein (ABP), auxin redistribution, auxin mechanism of action (activation of H+-ATPase) mediation by changes in [Ca2+]cyt and possible regulation of auxin-induced Ca2+ action b: calmodulin-activated or Ca2+-activated protein kinases (PK). b) Examine the involvement of ethylene in the gravitropic response of flower stems with regard to auxin-induced ethylene production and sensitivity of the tissue to ethylene. 3) Response: examine the effect of gravistimulation on invertase (associated with growth and elongation) activity and invertase gene expression. 4) Commercial practice: develop practical and simple treatments to prevent bending of cut flowers grown for export. Revisions: 1) Model systems: in addition to snapdragon (Antirrhinum majus L.), 3 other model shoe systems, consisting of oat (Avena sativa) pulvini, Ornithogalun 'Nova' cut flowers and Arabidopsis thaliana inflorescence, were targeted to confirm a more general mechanism for shoot gravitropism. 2 Research topics: the involvement of ABP, auxin action, PK and invertase in the gravitropic response of snapdragon stems could not be demonstrated. Alternatively, the involvement in the gravity signaling cascade of several other physiological mediators apart of [Ca2+]cyt such as: IP3, protein phosphorylation and actin cytoskeleton, was shown. Additional topics introduced: starch statolith reorientation, differential expression of early auxin responsive genes, and differential shoot growth. Background to the topic: The gravitropic bending response of flowering shoots occurring upon their horizontal placement during shipment exhibits a major horticultural problem. In spite of extensive studies in various aboveground organs, the gravitropic response was hardly investigated in flowering shoots. Being a complex multistep process that requires the participation of various cellular components acting in succession or in parallel, analysis of the negative gravitropic response of shoot includes investigation of signal transduction elements and various regulatory physiological mediators. Major achievements: 1) A correlative role for starch statoliths as gravireceptors in flowering shoot was initially established. 2) Differentially phosphorylated proteins and IP3 levels across the oat shoe pulvini, as well as a differential appearance of 2 early auxin-responsive genes in snapdragon stems were all detected within 5-30 minutes following gravistimulation. 3) Unlike in roots, involvement of actin cytoskeleton in early events of the gravitropic response of snapdragon shoots was established. 4) An asymmetric IAA distribution, followed by an asymmetric ethylene production across snapdragon stems was found following gravistimulation. 5) The gravity-induced differential growth in shoots of snapdragon was derived from initial shrinkage of the upper stem side and a subsequent elongation o the lower stem side. 6) Shoot bending could be successfully inhibited by Ca2+ antagonists (that serve as a basis for practical treatments), kinase and phosphatase inhibitors and actin-cytoskeleton modulators. All these agents did not affect vertical growth. The essential characterization of these key events and their sequence led us to the conclusion that blocking gravity perception may be the most powerful means to inhibit bending without hampering shoot and flower growth after harvest. Implications, scientific and agriculture: The innovative results of this project have provided some new insight in the basic understanding of gravitropism in flower stalks, that partially filled the gap in our knowledge, and established useful means for its control. Additionally, our analysis has advanced the understanding of important and fundamental physiological processes involved, thereby leading to new ideas for agriculture. Gravitropism has an important impact on agriculture, particularly for controlling the bending of various important agricultural products with economic value. So far, no safe control of the undesired bending problem of flower stalks has been established. Our results show for the first time that shoot bending of cut flowers can be inhibited without adverse effects by controlling the gravity perception step with Ca2+ antagonists and cytoskeleton modulators. Such a practical benefit resulting from this project is of great economic value for the floriculture industry.
8
Barash, Itamar, J. Mina Bissell, Alexander Faerman, and Moshe Shani. Modification of Milk Composition via Transgenesis: The Role of the Extracellular Matrix in Regulating Transgene Expression. United States Department of Agriculture, July 1995. http://dx.doi.org/10.32747/1995.7570558.bard.
Full textAbstract:
Altering milk composition via transgenesis depends on three main factors. (1) The availability of an efficient regulatory sequences for targeting transgene(s) to the mammary gland; (2) a reliable in vitro model to test the expression of transgenes prior to their introduction to the animal genome; and (3) better understanding of the major factors which determine the rate of gene expression and protein synthesis. The current studies provide the necessary means and knowledge to alter milk protein composition via transgenesis. The following specific goals were achieved: a: Identifying regulatory regions in the b-lactoglobulin (BLG) gene and the cross-talk between elements which enabled us to construct an efficient vector for the expression of desirable cDNA's in the mammary gland. b: The establishment of a sheep mammary cell line that serves as a model for the analysis of endogenous and exogenous milk protein synthesis in the mammary gland of livestock. c: An accurate comparison of the potency of the 5' regulatory sequences from the BLG and whey acidic protein (WAP) promoters in directing the expression of human serum albumin (HSA) to the mammary gland in vitro and in vivo. In this study we have also shown that sequences within the coding region may determine a specific pattern of expression for the transgene, distinct from that of the native milk protein genes. d: Characterizing the dominant role of ECM in transgene expression in mammary epithelial cells. e: Further characterization of the BCE-1 enhancer element in the promoter of the b-casein gene as a binding site for the c/EBP-b and Stat5. Identifying its interaction with chromatin and its up regulation by inhibitors of histone deacetylation. f: Identifying a mechanism of translational control as a mediator for the synergistic effect of insulin and prolactin on protein synthesis in the mammary gland.
9
Philosoph-Hadas, Sonia, Peter B. Kaufman, Shimon Meir, and Abraham H. Halevy. Inhibition of the Gravitropic Shoot Bending in Stored Cut Flowers Through Control of Their Graviperception: Involvement of the Cytoskeleton and Cytosolic Calcium. United States Department of Agriculture, December 2005. http://dx.doi.org/10.32747/2005.7586533.bard.
Full textAbstract:
Original objectives: The basic goal of the present project was to study the mechanism involved in shoot graviperception and early transduction, in order to determine the sequence of events operating in this process. This will enable to control the entire process of gravity-induced differential growth without affecting vertical growth processes essential for development. Thus, several new postulated interactions, operating at the perception and early transduction stages of the signaling cascade leading to auxin-mediated bending, were proposed to be examined in snapdragon spikes and oat shoot pulvini, according to the following research goals: 1) Establish the role of amyloplasts as gravireceptors in shoots; 2) Investigate gravity-induced changes in the integrity of shoot actin cytoskeleton (CK); 3) Study the cellular interactions among actin CK, statoliths and cell membranes (endoplasmic reticulum - ER, plasma membrane - PM) during shoot graviperception; 4) Examine mediation of graviperception by modulations of cytosolic calcium - [Ca2+]cyt, and other second messengers (protein phosphorylation, inositol 1,4,5-trisphosphate - IP3). Revisions: 1) Model system: in addition to snapdragon (Antirrhinum majus L.) spikes and oat (Avena sativa) shoot pulvini, the model system of maize (Zea mays) primary roots was targeted to confirm a more general mechanism for graviperception. 2) Research topic: brassinolide, which were not included in the original plan, were examined for their regulatory role in gravity perception and signal transduction in roots, in relation to auxin and ethylene. Background to the topic: The negative gravitropic response of shoots is a complex multi-step process that requires the participation of various cellular components acting in succession or in parallel. Most of the long-lasting studies regarding the link between graviperception and cellular components were focused mainly on roots, and there are relatively few reports on shoot graviperception. Our previous project has successfully characterized several key events occurring during shoot bending of cut flowers and oat pulvini, including amyloplast displacement, hormonal interactions and differential growth analysis. Based on this evidence, the present project has focused on studying the initial graviperception process in flowering stems and cereal shoots. Major conclusions and achievements: 1) The actin and not the microtubule (MT) CK is involved in the graviperception of snapdragon shoots. 2) Gravisensing, exhibited by amyloplast displacement, and early transduction events (auxin redistribution) in the gravitropic response of snapdragon spikes are mediated by the acto-myosin complex. 3) MTs are involved in stem directional growth, which occurs during gravitropism of cut snapdragon spikes, but they are not necessary for the gravity-induced differential growth. 4) The role of amyloplasts as gravisensors in the shoot endodermis was demonstrated for both plant systems. 5) A gravity-induced increase in IP.
10
Sessa, Guido, and Gregory B. Martin. molecular link from PAMP perception to a MAPK cascade associated with tomato disease resistance. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597918.bard.
Full textAbstract:
The research problem: The detection of pathogen-associated molecular patterns (PAMPs) by plant pattern recognition receptors (PRRs) is a key mechanism by which plants activate an effective immune response against pathogen attack. MAPK cascades are important signaling components downstream of PRRs that transduce the PAMP signal to activate various defense responses. Preliminary experiments suggested that the receptor-like cytoplasmickinase (RLCK) Mai5 plays a positive role in pattern-triggered immunity (PTI) and interacts with the MAPKKK M3Kε. We thus hypothesized that Mai5, as other RLCKs, functions as a component PRR complexes and acts as a molecular link between PAMP perception and activation of MAPK cascades. Original goals: The central goal of this research was to investigate the molecular mechanisms by which Mai5 and M3Kε regulate plant immunity. Specific objectives were to: 1. Determine the spectrum of PAMPs whose perception is transmitted by M3Kε; 2. Identify plant proteins that act downstream of M3Kε to mediate PTI; 3. Investigate how and where Mai5 interacts with M3Kε in the plant cell; 4. Examine the mechanism by which Mai5 contributes to PTI. Changes in research directions: We did not find convincing evidence for the involvement of M3Kε in PTI signaling and substituted objectives 1 and 3 with research activities aimed at the analysis of transcriptomic profiles of tomato plants during the onset of plant immunity, isolation of the novel tomato PRR FLS3, and investigation of the involvement of the RLCKBSKs in PTI. Main achievements during this research program are in the following major areas: 1. Functional characterization of Mai5. The function of Mai5 in PTI signaling was demonstrated by testing the effect of silencing the Mai5 gene by virus-induced gene silencing (VIGS) experiments and in cell death assays. Domains of Mai5 that interact with MAPKKKs and subcellular localization of Mai5 were analyzed in detail. 2. Analysis of transcriptional profiles during the tomato immune responses to Pseudomonas syringae (Pombo et al., 2014). We identified tomato genes whose expression is induced specifically in PTI or in effector-triggered immunity (ETI). Thirty ETI-specific genes were examined by VIGS for their involvement in immunity and the MAPKKK EPK1, was found to be required for ETI. 3. Dissection of MAP kinase cascades downstream of M3Kε (Oh et al., 2013; Teper et al., 2015). We identified genes that encode positive (SGT and EDS1) and negative (WRKY1 and WRKY2) regulators of the ETI-associated cell death mediated by M3Kε. In addition, the MKK2 MAPKK, which acts downstream of M3Kε, was found to interact with the MPK3 MAPK and specific MPK3 amino acids involved interaction were identified and found to be required for induction of cell death. We also identified 5 type III effectors of the bacterial pathogen Xanthomonaseuvesicatoria that inhibited cell death induced by components of ETI-associated MAP kinase cascades. 4. Isolation of the tomato PRR FLS3 (Hind et al., submitted). FLS3, a novel PRR of the LRR-RLK family that specifically recognizes the flagellinepitope flgII-28 was isolated. FLS3 was shown to bind flgII-28, to require kinase activity for function, to act in concert with BAK1, and to enhance disease resistance to Pseudomonas syringae. 5. Functional analysis of RLCKs of the brassinosteroid signaling kinase (BSK) family.Arabidopsis and tomato BSKs were found to interact with PRRs. In addition, certain ArabidospsisBSK mutants were found to be impaired in PAMP-induced resistance to Pseudomonas syringae. Scientific and agricultural significance: Our research activities discovered and characterized new molecular components of signaling pathways mediating recognition of invading pathogens and activation of immune responses against them. Increased understanding of molecular mechanisms of immunity will allow them to be manipulated by both molecular breeding and genetic engineering to produce plants with enhanced natural defense against disease.