Significant Direct Effect (significant + direct_effect)

Distribution by Scientific Domains


Selected Abstracts


The Effect of National Governance Codes on Firm Disclosure Practices: Evidence from Analyst Earnings Forecasts

CORPORATE GOVERNANCE, Issue 6 2008
John Nowland
ABSTRACT Manuscript Type: Empirical Research Question: This study examines whether voluntary national governance codes have a significant effect on company disclosure practices. Two direct effects of the codes are expected: 1) an overall improvement in company disclosure practices, which is greater when the codes have a greater emphasis on disclosure; and 2) a leveling out of disclosure practices across companies (i.e., larger improvements in companies that were previously poorer disclosers) due to the codes new comply-or-explain requirements. The codes are also expected to have an indirect effect on disclosure practices through their effect on company governance practices. Research Findings/Results: The results show that the introduction of the codes in eight East Asian countries has been associated with lower analyst forecast error and a leveling out of disclosure practices across companies. The codes are also found to have an indirect effect on company disclosure practices through their effect on board independence. Practical Implications: This study shows that a regulatory approach to improving disclosure practices is not always necessary. Voluntary national governance codes are found to have both a significant direct effect and a significant indirect effect on company disclosure practices. In addition, the results indicate that analysts in Asia do react to changes in disclosure practices, so there is an incentive for small companies and family-owned companies to further improve their disclosure practices. [source]


Separating host-tree and environmental determinants of honeydew production by Ultracoelostoma scale insects in a Nothofagus forest

ECOLOGICAL ENTOMOLOGY, Issue 4 2007
ROGER J. DUNGAN
Abstract 1.,Sugar-rich honeydew excreted (,produced') by insects feeding on phloem sap is a key energy flow in a range of temperate and tropical ecosystems. The present study measured honeydew produced by Ultracoelostoma sp. (Homoptera: Coelostomidiidae) scale insects feeding on Nothofagus solandri var. solandri (Hook f.) Oerst. trees in a temperate evergreen forest in New Zealand. Simultaneous measurements of environmental variables and canopy photosynthesis were conducted to allow separation of host-tree and environmental determinants of honeydew production. These relationships were further examined in experiments where canopy photosynthesis was manipulated by shading or plant nitrogen levels increased by foliar spray. 2.,Rates of honeydew production varied nine-fold from a maximum (± 1 SE) of 64.4 ± 15.2 mg dry mass m,2 bark h,1 in early summer (December) to a minimum of 7.4 ± 4.2 mg m,2 h,1 in winter (August). Rates of production measured 1.4 m from the base of the trees' stems varied significantly with stem diameter, and were higher on medium-sized (18 cm diameter) than small or large stems. 3.,Rates of production were significantly related to environmental conditions over the hours preceding measurement (air temperature and air saturation deficit averaged over the preceding 24 and 12 h respectively). There was no evidence that rates of production were directly related to short-term changes in the supply of carbohydrates from the canopy (either when compared with measurements of unmanipulated photosynthetic rate, or after sugar levels were manipulated by shading 80% of host-trees' leaf area), or to changes in phloem nitrogen content. 4.,The results show that there is no clear effect of host-tree carbon supply on honeydew production; if production is related to photosynthesis, the effect of this is much less important that the large and significant direct effect of environmental conditions on honeydew production. [source]


An analysis of predictors of team satisfaction in product development teams with differing levels of virtualness

R & D MANAGEMENT, Issue 5 2009
Eric M. Stark
The purpose of this study is to empirically examine and assess the moderating effects of extent of virtualness on a variety of well-established predictors of new product development team satisfaction. We focus our study on 178 different new product development teams from a variety of industries and use extent of virtualness as a structural characteristic of the teams, measuring it on a continuum. The predictors of team satisfaction we studied are relationship conflict, familiarity, goal clarity and preference for group work. Primary findings include: (1) relationship conflict has a more deleterious effect on team member satisfaction as teams become more virtual, mainly because it is very difficult for team members of virtual teams to resolve their interpersonal disputes; (2) the relationship between preference for group work and team satisfaction is moderated by extent of virtualness, such that preference for group work increases team satisfaction more as virtualness increases; (3) goal clarity and familiarity are not moderated by extent of virtualness, but have a significant direct effect on team satisfaction. Managerial and research implications of these findings relative to new product development teams are also discussed. [source]


Ability of N -acetylcarnosine to protect lens crystallins from oxidation and oxidative damage by radical probe mass spectrometry (RP-MS)

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 19 2010
Ji-won Ha
The application of Radical Probe Mass Spectrometry based on protein footprinting studies is described to investigate the effectiveness of the antioxidant N -acetylcarnosine (NAC) in preventing oxidative damage to lens crystallins present in the eye of mammals. Despite separate clinical trials which have reported the benefit of administering NAC to the eye as a 1% topical solution for the treatment of human cataract, no evidence was found to suggest that the antioxidant had any significant direct effect on reducing the levels of oxidation within the most abundant lens crystallins, , and ,-crystallin, at the molecular level at increasing concentrations of NAC. The results of this laboratory study suggest that the therapeutic benefit demonstrated in clinical trials is associated with the nature or formulation of the topical solution and/or that the mode of action of NAC as an antioxidant is not a direct one. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Determinants of physical activity among Taiwanese adolescents: An application of the health promotion model,

RESEARCH IN NURSING & HEALTH, Issue 1 2002
Tsu-Yin Wu
Abstract The purpose of this study was to examine the relationships among interpersonal influences (i.e., social support, norms, modeling), behavior-specific cognitions (i.e., self-efficacy, perceived benefits/barriers), competing demands, and physical activity among Taiwanese adolescents (N,=,832). The results from structural equation modeling indicated that perceived self-efficacy was the most important predictor of physical activity. Interpersonal influences, when considered in total, had a weak and nonsignificant direct effect on physical activity but had indirect effects on physical activity thorough perceived benefits and perceived self-efficacy. When sources of interpersonal influences were considered separately, parental influences did not have direct effects on physical activity. In contrast, peers did have a significant direct effect on physical activity and also indirect influences on physical activity through perceived self-efficacy. All variables accounted for 30% of the variance in physical activity. Results of this study identify important influences useful to health professionals for promoting physical activity in this population. © 2002 John Wiley & Sons, Res Nurs Health 25:25,36, 2002. [source]


Do delay aversion and executive function deficits make distinct contributions to the functional impact of ADHD symptoms?

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 11 2007
A study of early academic skill deficits
Background:, The present study examined the distinct properties of executive functioning in relation to ADHD symptoms, as well as functional outcomes associated with ADHD. In line with the dual-pathway model of ADHD, executive functioning and delay aversion were expected to show independent effects on ADHD symptoms. Furthermore, relations to early academic skills were examined, and it was hypothesized that the two processes of the dual-pathway model can be differentiated in terms of their effect on academic skill deficits, such that EF deficits, but not delay aversion, mediate the link between ADHD and academic functioning. Results:, As hypothesized, both EF deficits and delay aversion were independently related to ADHD symptoms. However, when conducting separate analyses for the two ADHD symptom domains, only the effect of EF deficits was independently related to symptoms of inattention, whereas only the effect of delay aversion was independently related to symptoms of hyperactivity/impulsivity. The mediation analysis showed that EF deficits, but not delay aversion, act as a mediator in the relation between symptoms of inattention and both mathematics and language skills. In addition, there was also a significant direct effect of inattention on early academic skills. Conclusions:, The findings of the present study are of importance for current models of heterogeneity in ADHD as they 1) provide further support for the notion that EF deficits and delay aversion are two possible pathways to ADHD, 2) add new interesting knowledge by showing that EF deficits and delay aversion can be differentiated in terms of their relations to the two ADHD symptom domains, and 3) indicate that the two processes of the dual-pathway model can also be differentiated in terms of their effect on functional impairments associated with ADHD. [source]


Parental Education and Child Health: Evidence from China,

ASIAN ECONOMIC JOURNAL, Issue 1 2006
Pushkar Maitra
J1; C31; C35 This paper examines the effect of parental, household and community character-istics on the health of children in China. We find that birth order, death of elder siblings, use of prenatal care and alcohol consumption by the mother when pregnant have statistically significant effects on the health of children. Although parental education does not have a significant direct effect on child health, it does affect mothers' behavior during pregnancy and inflfluences the use of health inputs, indirectly impacting the health of children. The research findings have important implications for both family planning programs and broader social policies in China. [source]


Environmental controls and patterns of cumulative radial increment of evergreen tree species in montane, temperate rainforests of Chiloé Island, southern Chile

AUSTRAL ECOLOGY, Issue 3 2009
CECILIA A. PÉREZ
Abstract We investigated the local environmental controls on daily fluctuations of cumulative radial increment and cambial hydration of three dominant, evergreen tree species from montane, Coastal rainforests of Chiloé Island, Chile (42° 22, S). During 2 years (1997,1998 and 1998,1999) we recorded hourly cumulative radial increments using electronic band dendrometers in the long-lived conifer Fitzroya cupressoides (Cupressaceae), the evergreen broad-leaved Nothofagus nitida (Nothofagaceae), and the narrow-leaved conifer Podocarpus nubigena (Podocarpaceae). We also measured soil and cambial tissue hydration using capacitance sensors, together with air and soil temperature and rainfall during the period of the study. In addition, we collected cores of these tree species to evaluate how dendrometer measurements reflect annual tree ring width. One-year long daily time series of cumulative radial increments suggests that radial growth of Fitzroya cupressoides was initiated slowly in early spring, with a maximum in early summer. Multiple regressions showed positive relations between daily precipitation and radial index (i.e. the difference in cumulative radial increment of two consecutive days) in the three species. According to path analysis there was a significant direct effect of changes in tree hydration on radial index of the three focal species. In emergent, pioneer species such as Nothofagus and Fitzroya, radial index was negatively affected by changes in maximum air temperature and photosynthetically active radiation, probably because of high evapotranspiration demand on warm sunny days. The shade-tolerant species Podocarpus nubigena was positively affected by photosynthetically active radiation. Our diel scale findings support the use of tree ring widths for reconstructing past climate in these southern temperate forests and provide evidence that rainforest trees may be highly sensitive to future declines in rainfall and temperature increases during summer. [source]