Whether, how and when do leaders engage in ethical leadership as a response to status threat? We propose that leaders facing status threat are likely to develop ethical leadership behaviors toward ...subordinates. Drawing on power dependence theory, we theorize that experiencing status threat augments leaders' dependence on subordinates who can provide them with status-relevant resources (e.g., performance, loyalty and trust). Dependence on subordinates further motivates leaders to absorb the resource constraints through displaying ethical leadership. However, if leaders are able to obtain alternative resources to cope with status threat, their dependence on subordinates is weakened. We conducted two studies to test the predictions. Using a moderation-of-process design, Study 1 found that when participants experienced status threat, they displayed more ethical leadership behaviors, but particularly so when their reward structure was team- rather than individual-based. Study 2 was a field study using a sample of 104 teams from two Chinese firms listed in the "Top 500 private enterprises in China." We found that leaders who experienced more status threat were perceived to be more ethical by their subordinates, which was mediated by leaders' perceptions of dependence on subordinates. The mediated effect was stronger (weaker) for leaders who were less (more) skilled in networking. Implications for theory on the contextual factors of ethical leadership, dependence, and status threat are discussed.
Graduate students' academic misconduct has received increasing attention. Although past literature has emphasized university faculty as an important influencing factor on students' moral behaviors, ...the mechanisms must be further disclosed. We investigated how supervisors' ethical leadership influenced graduate students' attitudes toward academic misconduct. We explained why and how supervisor gender affects post-graduate students' social learning process by integrating social cognitive theory and role congruity theory. Study 1 used a sample of 301 graduate students in 60 academic teams in four Chinese business schools. Study 2 used experimental vignette methodology to enhance the findings' internal and external validity and provided evidence of causality. Based on the two complementary studies, we found that supervisors' ethical leadership significantly inhibited students' acceptance of academic misconduct through students' moral efficacy and the ethical climate of the academic team. The indirect effect via moral efficacy was more significant s for female supervisors. Implications for ethical leadership, academic misconduct, gender differences in leadership, and moral education were discussed.
How to effectively reinforce steel structures with rust and damage is an important research topic in the engineering field. This article takes the rusted I-beam as the research object and analyzes ...the effects of different CFRP/GFRP reinforcement methods on the bending performance of rusted I-beams through experimental research with a total of 1 unreinforced beam and 7 CFRP/GFRP-reinforced beams. The results show that when the number of CFRP/GFRP-reinforced layers is the same, replacing some of the CFRP with GFRP and using different interlayer mixed laying sequences have little effect on the bending bearing capacity of rusted I-beams. The number of CFRP/GFRP-reinforced layers is the key factor affecting the bending bearing capacity. At the same time, numerical simulation was conducted using finite element software to study the stress distribution and stress development law of the reinforced beam, and the numerical simulation results were consistent with the experimental results.
Carbon/carbon (C/C) composites have received considerable attention for one of the most promising materials in thermal-structural applications owing to their low density, excellent mechanical ...strength at high temperature, and superior thermal shock resistance. However, C/C composites are susceptible to destructive oxidation in atmospheric environment at high temperature. Matrix modification by adding ultra-high-temperature ceramics (UHTCs) into carbon substrate has been proved to be a favorable route to achieve the improved ablation resistance of C/C composites. In this work, the main fabrication approaches of UHTCs-modified C/C composites were summarized, including chemical vapor infiltration/deposition, precursor infiltration and pyrolysis, reactive melt infiltration, and slurry infiltration, and the advantages and drawbacks of each process were also briefly analyzed. In addition, anti-ablation properties of UHTCs-modified C/C composites under different ablation tests with different shape specimens were introduced. Finally, some likely future challenges and research directions in the development and application of these materials were presented.
Lignin, a characteristic component of terrestrial plants. Rivers transport large amounts of vascular plant organic matter into the oceans where lignin can degrade over time; however, microorganisms ...involved in this degradation have not been identified. In this study, several bacterial strains were isolated from marine samples using the lignin-derived compound vanillic acid (4-hydroxy-3-methoxybenzoic acid) as the sole carbon and energy source. The optimum growth temperature for all isolates ranged from 30 to 35°C. All isolates grew well in a wide NaCl concentration range of 0 to over 50 g/L, with an optimum concentration of 22.8 g/L, which is the same as natural seawater. Phylogenetic analysis indicates that these strains are the members of Halomonas, Arthrobacter, Pseudoalteromonas, Marinomonas, and Thalassospira. These isolates are also able to use other lignin-derived compounds, such as 4-hydroxybenzoic acid, ferulic acid, syringic acid, and benzoic acid. Vanillic acid was detected in all culture media when isolates were grown on ferulic acid as the sole carbon source; however, no 4-hydroxy-3-methoxystyrene was detected, indicating that ferulic acid metabolism by these strains occurs via the elimination of two side chain carbons. Furthermore, the isolates exhibit 3,4-dioxygenase or 4,5-dioxygenase activity for protocatechuic acid ring-cleavage, which is consistent with the genetic sequences of related genera. This study was conducted to isolate and characterize marine bacteria of degrading lignin-derived compounds, thereby revealing the degradation of aromatic compounds in the marine environment and opening up new avenues for the development and utilization of marine biological resources.
Porous titanium is a functional structural material with certain porosity, which is prepared from titanium powder and titanium fiber. In order to study the porosity, phase structure, microstructure, ...sintering mechanism and mechanical properties of porous titanium obtained by spark plasma sintering of a Ti powder⁻fiber mixture at different sintering temperatures, a spherical titanium powder (D
of 160 μm) was prepared via plasma rotating electrode processing, and titanium fiber (average wire diameter of fiber of 110 μm) was prepared by drawing, and they were mixed as raw materials according to different mass ratios. Porous titanium with a fiber⁻powder composite porous structure was prepared by spark plasma sintering at sintering temperatures of 800 °C, 900 °C and 1000 °C under a sintering pressure of 20 MPa. The results showed that there were no new phases occurring in porous titanium with porosity of 1.24⁻24.6% after sintering. Titanium fiber and titanium powder were sintered using powder/powder, powder/fiber and fiber/fiber regimes to form composite pore structures. The mass transfer mechanism of the sintered neck was a diffusion-dominated material migration mechanism during sintering. At higher sintering temperatures, the grain size was larger, and the fiber (800 °C; 10⁻20 μm) was finer than the powder (800 °C; 10⁻92 μm). The stress⁻strain curve of porous titanium showed no obvious yield point, and the compressive strength was higher at higher sintering temperatures. The results of this paper can provide data reference for the preparation of porous titanium obtained by spark plasma sintering of a Ti powder⁻fiber mixture.
Studies have suggested that firms can benefit from bridging two or more otherwise disconnected firms in their ego networks (i.e., structural holes) as a potentially useful source of external ...knowledge for innovation. However, past research also noted that the relationship between bridging structural holes and firm innovation varies significantly. Building on the earlier research that has examined the industrial, structural, and institutional dimensions of this relationship, the purpose of this research is to study how the different characteristics of the external knowledge provided by bridging structural holes in a focal firm’s ego network might moderate the relationship between bridging structural holes and firm innovation. Using longitudinal data from the U.S. computer industry, this study showed that focal firms that bridged otherwise disconnected firms in their ego networks enjoyed higher levels of innovation. In addition, it showed that this relationship was particularly stronger when the focal firms and the disconnected firms that they bridged operated in similar rather than different markets but when the focal firms and the disconnected firms worked on different rather than similar technological domains. The results also revealed that the relationship was stronger when the focal firms’ knowledge specialization was low rather than high and when the focal firms emphasized incremental rather than breakthrough innovation. These findings show companies how they can benefit from bridging otherwise disconnected firms in their ego networks and help them make more informed decisions pertaining to such bridging activities.
Purpose
The use of social media is an integral part of modern life, yet the impact of social media on creativity is a paradox. Drawing on the conservation of resources theory, the authors propose ...that social media, as an ecological condition, both nurture and deplete resources. Accordingly, the authors investigated two inconsistent mechanisms: creative self-efficacy and ego depletion.
Design/methodology/approach
Study 1 established the within-person effects of social media use on creativity by tracking 64 college students for five working days. Using a sample of 493 employee–leader-matched dyads in a national bank, Study 2 tested the entire model. Study 3 is a follow-up experiment based on a sample of 160 participants.
Findings
The results consistently showed that: (1) social media use had a positive impact on creativity in general; (2) social media use increased ego depletion and creative self-efficacy, which were two inconsistent mediators; (3) hedonic use of social media reduced the negative impact of cognitive use of social media on ego depletion.
Originality/value
This research sheds new light on the paradox between social media use and creativity and highlights the benefits of the balanced use of social media features. This research has implications for creative stimulation and job design in digital contexts.
Porous titanium samples with a porosity of 1.34~15.54% were prepared by a spark plasma sintering (SPS) process at sintering temperatures of 800 °C, 850 °C and 900 °C, and a sintering pressure of 10 ...MPa. The microstructures and fracture morphology of the samples were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The compressive strength and elastic modulus were likewise measured. The results showed that no new phase occurred after the samples were sintered, and the main phases were α phase of hcp structure. The porosity of the samples decreased significantly with the increase of sintering temperature. At 800 °C, the sample phase was dominated by equiaxed α. There were more irregular coarse pores in the samples. At 850 °C, the microstructure was mainly zigzag α, and the pores were finely and relatively uniform in distribution. At 900 °C, the sample’s structure transformed into a dense sheet-like α. The sample’s densities increased and the pores disappeared. The room temperature compression test showed that the porous titanium sintered by SPS had excellent compressive strength. The yield strength, compressive strength, compressive strain and elastic modulus were 81.85~122.36 MPa, 161.65~498.86 MPa, 36.75~59.97% and 2.79~4.22 GPa, respectively.
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