Is there an inverted U-shape relationship between job demands and work engagement : the moderating role of social support

Purpose - The purpose of this paper is to examine the possibility of an inverted U-shaped relationship between job demands and work engagement, and whether social support moderates this relationship. Design/methodology/approach – This study uses 307 technical and information technology (IT) managers who responded to an online survey. Multiple regressions are employed to examine linear and curvilinear relationship among variables. Findings – Overall, results support the applicability of the quadratic effect of job demands on employee engagement. However, only supervisor support, not colleague support, moderated the relationship between job demands and work engagement. Originality/value – The paper is the first to shed light on the quadratic effect of job demands on work engagement. The findings have noteworthy implications for managers to design optimal job demands that increase employee engagement.

The impact of gender diversity on performance in services and manufacturing organizations

We present three competing predictions of the organizational gender diversity-performance relationship: a positive linear prediction, a negative linear prediction, and an inverted U-shaped curvilinear prediction. The paper also proposes a moderating effect of industry type (services vs. manufacturing). The predictions were tested using archival quantitative data with a longitudinal design. The results show partial support for the positive linear and inverted U-shaped curvilinear predictions as well as for the proposed moderating effect of industry type. The results help reconcile the inconsistent findings of past research. The findings also show that industry context can strengthen or weaken gender diversity effects.

The gender diversity-performance relationship in services and manufacturing organizations

Empirical findings on the link between gender diversity and performance have been inconsistent. This paper presents three competing predictions of the organizational gender diversity-performance relationship: a positive linear prediction derived from the resource-based view of the firm, a negative linear prediction derived from self-categorization and social identity theories, and an inverted U-shaped curvilinear prediction derived from the integration of the resource-based view of the firm with self-categorization and social identity theories. This paper also proposes a moderating effect of industry type (services vs. manufacturing) on the gender diversity-performance relationship. The predictions were tested in publicly listed Australian organizations using archival quantitative data with a longitudinal research design. The results show partial support for the positive linear and inverted U-shaped curvilinear predictions as well as for the proposed moderating effect of industry type. The curvilinear relationship indicates that different proportions of organizational gender diversity have different effects on organizational performance, which may be attributed to different dynamics as suggested by the resource-based view and self-categorization and social identity theories. The results help reconcile the inconsistent findings of past research that focused on the linear gender diversity-performance relationship. The findings also show that industry context can strengthen or weaken the effects of organizational gender diversity on performance.

Larger or broader : performance implications of size and diversity of the knowledge worker's egocentric network. [更多或更广：知识员工个人中心网络大小和 多样性对绩效的影响]

Management scholars and practitioners emphasize the importance of the size and diversity of a knowledge worker's social network. Constraints on knowledge workers’ time and energy suggest that more is not always better. Further, why and how larger networks contribute to valuable outcomes deserves further understanding. In this study, we offer hypotheses to shed insight on the question of the diminishing returns of large networks and the specific form of network diversity that may contribute to innovative performance among knowledge workers. We tested our hypotheses using data collected from 93 R&D engineers in a Sino-German automobile electronics company located in China. Study findings identified an inflection point, confirming our hypothesis that the size of the knowledge worker's egocentric network has an inverted U-shaped effect on job performance. We further demonstrate that network dispersion richness (the number of cohorts that the focal employee has connections to) rather than network dispersion evenness (equal distribution of ties across the cohorts) has more influence on the knowledge worker's job performance. Additionally, we found that the curvilinear effect of network size is fully mediated by network dispersion richness. Implications for future research on social networks in China and Western contexts are discussed.

Board age and gender diversity : a test of competing linear and curvilinear predictions

The inconsistent findings of past board diversity research demand a test of competing linear and curvilinear diversity–performance predictions. This research focuses on board age and gender diversity, and presents a positive linear prediction based on resource dependence theory, a negative linear prediction based on social identity theory, and an inverted U-shaped curvilinear prediction based on the integration of resource dependence theory with social identity theory. The predictions were tested using archival data on 288 large organizations listed on the Australian Securities Exchange, with a 1-year time lag between diversity (age and gender) and performance (employee productivity and return on assets). The results indicate a positive linear relationship between gender diversity and employee productivity, a negative linear relationship between age diversity and return on assets, and an inverted U-shaped curvilinear relationship between age diversity and return on assets. The findings provide additional evidence on the business case for board gender diversity and refine the business case for board age diversity.

Which industry is greener? An empirical study of nine industries in OECD countries

This study analyzed the relationship between the CO2 emissions of different industries and economic growth in OECD countries from 1970 to 2005. We tested an environmental Kuznets curve (EKC) hypothesis and found that total CO2 emissions from nine industries show an N-shaped trend instead of an inverted U or monotonic increasing trend with increasing income. The EKC hypothesis for sector-level CO2 emissions was supported in the (1) paper, pulp, and printing industry; (2) wood and wood products industry; and (3) construction industry. We also found that emissions from coal and oil increase with economic growth in the steel and construction industries. In addition, the non-metallic minerals, machinery, and transport equipment industries tend to have increased emissions from oil and electricity with economic growth. Finally, the EKC turning point and the relationship between GDP per capita and sectoral CO2 emissions differ among industries according to the fuel type used. Therefore, environmental policies for CO2 reduction must consider these differences in industrial characteristics. © 2013 Elsevier Ltd.

Corporate Environmental and Economic Performance of Japanese Manufacturing Firms: Empirical Study for Sustainable Development

This study examines the relationship between environmental performance and economic performance in Japanese manufacturing firms. The environmental performance indicators include CO2 emissions and the aggregate toxic risk associated with chemical emissions relative to sales. Return on assets (ROA) is used as an indicator of economic performance. We demonstrate that there is a significant inverted U-shaped relationship between ROA and environmental performance calculated by aggregated toxic risk. We also find that the environmental performance increases ROA through both returns on sales and improved capital turnover. However, we observe a significant positive relationship between financial performance and environmental performance based on CO2 emissions. These findings may provide evidence for the consequences of firms' environmental behavior and sustainable development. © 2012 John Wiley & Sons, Ltd and ERP Environment.

Stress at the synapse : signal transduction mechanisms of adrenal steroids at neuronal membranes

As the key neuron-to-neuron interface, the synapse is involved in learning and memory, including traumatic memories during times of stress. However, the signal transduction mechanisms by which stress mediates its lasting effects on synapse transmission and on memory are not fully understood. A key component of the stress response is the increased secretion of adrenal steroids. Adrenal steroids (e.g., cortisol) bind to genomic mineralocorticoid and glucocorticoid receptors (gMRs and gGRs) in the cytosol. In addition, they may act through membrane receptors (mMRs and mGRs), and signal transduction through these receptors may allow for rapid modulation of synaptic transmission as well as modulation of membrane ion currents. mMRs increase synaptic and neuronal excitability; mechanisms include the facilitation of glutamate release through extracellular signal-regulated kinase signal transduction. In contrast, mGRs decrease synaptic and neuronal excitability by reducing calcium currents through N-methyl-D-aspartate receptors and voltage-gated calcium channels by way of protein kinase A- and G protein-dependent mechanisms. This body of functional data complements anatomical evidence localizing GRs to the postsynaptic membrane. Finally, accumulating data also suggest the possibility that mMRs and mGRs may show an inverted U-shaped dose response, whereby glutamatergic synaptic transmission is increased by low doses of corticosterone acting at mMRs and decreased by higher doses acting at mGRs. Thus, synaptic transmission is regulated by mMRs and mGRs, and part of the stress signaling response is a direct and bidirectional modulation of the synapse itself by adrenal steroids.

Dissociable forms of repetition priming: A computational model

Nondeclarative memory and novelty processing in the brain is an actively studied field of neuroscience, and reducing neural activity with repetition of a stimulus (repetition suppression) is a commonly observed phenomenon. Recent findings of an opposite trend specifically, rising activity for unfamiliar stimuli—question the generality of repetition suppression and stir debate over the underlying neural mechanisms. This letter introduces a theory and computational model that extend existing theories and suggests that both trends are, in principle, the rising and falling parts of an inverted U-shaped dependence of activity with respect to stimulus novelty that may naturally emerge in a neural network with Hebbian learning and lateral inhibition. We further demonstrate that the proposed model is sufficient for the simulation of dissociable forms of repetition priming using real-world stimuli. The results of our simulation also suggest that the novelty of stimuli used in neuroscientific research must be assessed in a particularly cautious way. The potential importance of the inverted-U in stimulus processing and its relationship to the acquisition of knowledge and competencies in humans is also discussed

Cord blood 25-hydroxyvitamin D and fetal growth in the China-Anhui birth cohort study

We determined the association of cord blood 25-hydroxyvitamin D [25(OH)D] with birth weight and the risk of small for gestational age (SGA). As part of the China-Anhui Birth Cohort (C-ABC) study, we measured cord blood levels of 25(OH)D in 1491 neonates in Hefei, China. The data on maternal sociodemographic characteristics, health status, lifestyle, birth outcomes were prospectively collected. Multiple regression models were used to estimate the association of 25(OH)D levels with birth weight and the risk of SGA. Compared with neonates in the lowest decile of cord blood 25(OH)D levels, neonates in four deciles (the fourth, fifth, sixth and seventh deciles) had significantly increased birth weight and decreased risk of SGA. Multiple linear regression models showed that per 10 nmol/L increase in cord blood 25(OH)D, birth weight increased by 61.0 g (95% CI: 31.9, 89.9) at concentrations less than 40 nmol/L, and then decreased by 68.5 g (95% CI: −110.5, −26.6) at concentrations from 40 to 70 nmol/L. This study provides the first epidemiological evidence that there was an inverted U shaped relationship between neonatal vitamin D status and fetal growth, and the risk of SGA reduced at moderate concentration.

Identifying and implementing adaptive strategy in the U.S. military

Changes in the environment, including increased environmental complexity, require military supply units to employ a more adaptive strategy in order to enhance military agility. We extend the Lumpkin and Dess (1996) model and develop propositions that explore the interrelationships between/amongst entrepreneurial orientation (EO); opportunity recognition, evaluation and exploitation; environmental and organizational factors; and organizational performance. We propose that the innovativeness, proactiveness, and risk-taking dimensions of EO are of primary importance in identifying adaptive solutions and that these relationships are moderated by environmental factors. The autonomy and competitive aggressiveness dimensions of EO are important in implementing solutions as adaptive strategies, especially in a military context, and these relationships are moderated by organizational factors. This chapter extends existing theory developed primarily for the civilian sector to the military. Military organizations are more rigid hierarchical structures, and have different measures of performance. At an applied level, this research provides insights for military commanders that can potentially enhance agility and adaptability.

The role of timber plantations in U.K. investment portfolios

Although timber plantations and forests are classified as forms of agricultural production, the ownership of this land classification is not limited to rural producers. Timber plantations and forests are now regarded as a long-term investment with both institutional and absentee owners. While the NCREIF property indices have been the benchmarks for the measurement of the performance of the commercial property market in the UK, for many years the IPD timberland index has recently emerged as the U.K. forest and timberland performance indicator. The IPD Forest index incorporates 126 properties over five regions in the U.K. This paper will utilise the IPD Forestry Index to examine the performance of U.K. timber plantations and forests over the period 1981-2004. In particular, issues to be critically assessed include plantation and forest performance analysis, comparative investment analysis, and the role of plantations and forests in investment portfolios, the risk reduction and portfolio benefits of plantations and forests in mixed-asset portfolios and the strategic investment significance of U.K. timberlands.

Dislodgement of commercial property public debt markets : the case of U.S. and Australia

The paper investigates if there are any discernible trends in the U.S. and Australian commercial property public debt markets with the onset of the global financial crisis (GFC). Commercial mortgage-backed securities and unsecured bonds issued by real estate investment trusts for the period 2000 to Q3:2009 are reviewed. It is shown that events in the equity markets have an impact on the pricing of these two instruments. Furthermore, the impact of subdued activity in these financing instruments on the commercial property market is discussed.