Search results for "indirect effect"
showing 10 items of 18 documents
Hierarchy of factors impacting grape berry mass: separation of direct and indirect effects on major berry metabolites
2018
Final berry mass, a major quality factor in wine production, is determined by the integrated effect of biotic and abiotic factors that can also influence berry composition. Under field conditions, interactions between these factors complicate study of the variability of berry mass and composition. Depending on the observation scale, the hierarchy of the impact degree of these factors can vary. The present work examines the simultaneous effects of the major factors influencing berry mass and composition to create a hierarchy by impact degree. A second objective was to separate the possible direct effects of factors on berry composition from an indirect effect mediated through their impact on…
Territorial determinants and NUTS-3 regional performance: a spatial analysis for Italy across the crisis
2018
This paper analyses the differential impact of several territorial determinants of the economic performance of Italian provinces (NUTS 3 level). as measured by per capita GDP, export and employment growth from 1999 to 2014. It covers both the pre‐crisis and the crisis period and stresses the role of geographical proximity in shaping local performance over a wide set of explanatory variables. In order to do so, we employ, firstly, a spatial Durbin model which enables us to discriminate between direct and indirect effects and to highlight the possible contagion or crowding‐out spatial effects for each territorial dimension affecting growth. Then, we extend the analysis by allowing for the pos…
Latitudinal- and local-scale variations in a rocky intertidal interaction web
2015
Natural assemblages are structured by a complex combination of positive and negative interactions, and the relative importance of each interaction can vary across spatial scales. By using a simple interaction web (barnacles-grazers-microphytobenthos) in a rocky intertidal system, we tested the hypothesis that the relative strength of positive and negative interactions would vary as a function of different environmental stress between 2 latitudinal levels and local environmental conditions. We manipulated the cover of barnacles and the presence of limpets at 2 sites in northern and southern Italy and non-destructively examined the response of microphyto - benthos (MPB) (photosynthetic biomas…
Plant facilitation and phylogenetics
2013
The relationship between facilitation and evolutionary ecology is poorly understood. We review five issues elucidating how the phylogenetic relatedness of species provides insight into the role of facilitation in community assembly: (a) Are the facilitative interactions more common between species that differ in a regeneration niche? (b) Are facilitative interactions more common between distantly related species? (c) Do communities governed by facilitation (rather than competition) have higher phylogenetic diversity? (d) As facilitated juvenile plants mature, do they compete with their nurses more often if they are closely related to them? (e) How does the phylogenetic signature in a commun…
Environmentally driven changes in Baltic salmon oxidative status during marine migration.
2020
The fitness and recruitment of fish stocks can be markedly affected by environmental disturbances including global warming, eutrophication and contamination. Understanding the effects of environmental stressors on salmon physiology during marine residence is of a global concern as marine survival has decreased. We present a unique combination of physiological responses - antioxidant defence and oxidative damage biomarkers, stable isotopes and contaminant exposure biomarkers - measured from adult Atlantic salmon (Salmo salar) collected at the Baltic Sea and studied in relation to environmental variables and fitness estimates. The results demonstrate that feeding populations of salmon display…
The knowledge spillover effect of crowdfunding
2020
Knowledge exerts a positive indirect effect on the external environment. However, not all innovations are transferred to companies and society to allow such an effect to occur. Given the existence ...
Emotional Intelligence and Social Support: Two Key Factors in Preventing Occupational Stress during COVID-19
2021
Emotional intelligence (EI) and social support are among the most investigated hypothesized variables that affect stress at work. The current study aims to evaluate the direct association between EI and occupational stress and its indirect relationship mediated by three sources of social support during the spread of the COVID-19. The total sample was composed of 367 individuals (53.7% males), aged from 20 to 68 (M = 37.84, SD = 10.39), who filled out an online questionnaire. A mediation analysis was performed to test the hypothesized relationships. Our findings showed that EI has a direct effect on psychological effects and an indirect effect on almost all the facets of occupational stress.…
Life satisfaction and the mediating role of character strengths and gains in informal caregivers
2021
WHAT IS KNOWN ON THE SUBJECT?: The role of informal caregiver can have both negative and positive consequences for a person's well-being. The main theoretical framework for explaining these consequences is the stress process model, which considers contextual variables, stressors and mediating/moderating factors. The latter are psychosocial factors such as coping strategies, personal mastery, social support or beliefs and values which may influence caregiver well-being. The perception of gains in caregiving has also been proposed as a mediating variable since it may act as a coping strategy. However, few studies have examined values and perceived gains as mediating variables with life satisf…
Using meta-analytic path analysis to test theoretical predictions in health behavior: An illustration based on meta-analyses of the theory of planned…
2016
Abstract Objective Synthesizing research on social cognitive theories applied to health behavior is an important step in the development of an evidence base of psychological factors as targets for effective behavioral interventions. However, few meta-analyses of research on social cognitive theories in health contexts have conducted simultaneous tests of theoretically-stipulated pattern effects using path analysis. We argue that conducting path analyses of meta-analytic effects among constructs from social cognitive theories is important to test nomological validity, account for mediation effects, and evaluate unique effects of theory constructs independent of past behavior. We illustrate o…
Theoretical Study of Catalytic Efficiency of a Diels–Alderase Catalytic Antibody: An Indirect Effect Produced During the Maturation Process
2007
The Diels–Alder reaction is one of the most important and versatile transformations available to organic chemists for the construction of complex natural products, therapeutics agents, and synthetic materials. Given the lack of efficient enzymes capable of catalyzing this kind of reaction, it is of interest to ask whether a biological catalyst could be designed from an antibody-combining site. In the present work, a theoretical study of the different behavior of a germline catalytic antibody (CA) and its matured form, 39 A-11, that catalyze a Diels–Alder reaction has been carried out. A free-energy perturbation technique based on a hybrid quantum-mechanics/molecular-mechanics scheme, togeth…