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Noise-induced hearing loss (NIHL) affects a large number of military personnel and civilians. Regenerating inner-ear cochlear hair cells (HCs) is a promising strategy to restore hearing after NIHL. In this review, we first summarize recent transcriptome profile analysis of zebrafish lateral lines and chick utricles where spontaneous HC regeneration occurs after HC damage. We then discuss recent studies in other mammalian regenerative systems such as pancreas, heart and central nervous system. Both spontaneous and forced HC regeneration occurs in mammalian cochleae in vivo involving proliferation and direct lineage conversion. However, both processes are inefficient and incomplete, and decline with age. For direct lineage conversion in vivo in cochleae and in other systems, further improvement requires multiple factors, including transcription, epigenetic and trophic factors, with appropriate stoichiometry in appropriate architectural niche. Increasing evidence from other systems indicates that the molecular paths of direct lineage conversion may be different from those of normal developmental lineages. We therefore hypothesize that HC regeneration does not have to follow HC development and that epigenetic memory of supporting cells influences the HC regeneration, which may be a key to successful cochlear HC regeneration. Finally, we discuss recent efforts in viral gene therapy and drug discovery for HC regeneration. We hope that combination therapy targeting multiple factors and epigenetic signaling pathways will provide promising avenues for HC regeneration in humans with NIHL and other types of hearing loss.

PurposeThe purpose of this research is to investigate the effects of inter-organizational conflicts on the project added value in the Chinese construction industry, and also to examine the mediating effect of conflicts on project added value and the moderating effect of conflict management strategies.Design/methodology/approachA conceptual model was developed, and a structured questionnaire survey was conducted with 667 professionals. The structural equation modeling technique was used to analyze the data.FindingsThe results showed that task conflict, relationship conflict and process conflict were influenced by subject characteristics of project participants, bilateral relationship characteristics and project characteristics. Similarly, these three types of conflicts interact with each other. Meanwhile, these three types of conflicts influence the added value in construction projects, which are moderated by conflict management strategies. Under a collaborating strategy, task conflict and process conflict were positively associated with project added value, and relationship conflict was negatively associated with project added value. Under a competing strategy, task conflict, process conflict and relationship conflict were negatively associated with added value in construction projects. Therefore, the constructive and destructive effects of conflicts on project added value under different conflict management strategies are verified in Chinese construction projects.Research limitations/implicationsThe variables may not be exhaustive for construction projects and most of them were applied in construction projects for the first time. As a result, their rationality and effectiveness could be further improved. The results implied that inter-organizational conflicts had a constructive effect on project added value and should attract broad attention for future research. Additionally, different driving factors had different influences on these conflicts, and even the driving factors can be divided into different dimensions.Practical implicationsThis study provides a better understanding of the relationship between inter-organizational conflicts and added value in construction projects, and a reliable reference for the project manager to effectively deal with these conflicts. In addition, this research reveals the effects of conflicts on project added value and the path of conflicts transformation. This provides a useful reference for project managers to take advantage of the positive effect of task conflict and process conflict, and to avoid the negative effect of relationship conflict.Originality/valueVery few studies attempted to examine the effects of inter-organizational conflicts on project added value in construction projects. Therefore, this research makes significant theoretical and practical contributions to the existing body of knowledge on the conflict management and project added value. This research provides an empirical evidence to support the viewpoint that different types of conflicts can be mutually transformed. Similarly, this study explains how conflicts present functional and dysfunctional effects in construction projects. Both of them are potential theoretical contributions to the existing body of knowledge.

PurposeThis study aims to investigate how the strength of ties (i.e. strong ties and weak ties) in megaproject networks influences project performance in terms of types of conflicts.Design/methodology/approachA questionnaire survey was undertaken with professionals in Chinese megaprojects and 445 valid responses were received. A conflict-based theoretical model was developed and tested with structural equation modeling.FindingsThe results indicated that task conflict had a constructive effect on project performance, whereas relationship conflict and process conflict had destructive effects. Both strong and weak ties positively affected project performance, and that weak ties exerted greater effects on performance. The introduction of conflicts significantly weakened the effect of strong ties on project performance. Strong ties indirectly affected project performance via task conflict and relationship conflict, whereas weak ties affected performance only through task conflict. Task conflict had a constructive effect on project performance, whereas relationship conflict and process conflict had destructive impact.Research limitations/implicationsThis study identified the positive effect of strength of ties on project performance as well as the constructive and destructive roles of conflicts. Furthermore, the findings provided evidence that strength of ties and conflicts were critical factors for project performance. While, there are still limitations. There are other attributes of megaproject networks, such as network nodes' characteristics and network structure, which may influence conflicts and project performance. Future research would be conducted to explore the role of these variables. Meanwhile, because different types of conflicts may mutually transform under certain conditions, future research would also address this issue in megaprojects.Practical implicationsAs for the management strategies, project stakeholders should know the existence of project networks, exactly assess their resource endowment, especially their external and internal relationship network. In accordance with changes of the project network, stakeholders should share knowledge and learn techniques about how to respond to relationship disturbances, thus reducing relationship conflict and process conflict. Furthermore, stakeholders should place an emphasis on fostering and reinforcing communication and trust, thus effectively resolving task conflict, ambiguity and uncertainty engendered from network ties in a megaproject network.Originality/valueThe main contribution of this study is threefold. First, this study will enrich the literature on strength of ties by accentuating the roles of conflicts in megaproject context. Second, this study contributes to the theoretical development of a conceptual model for explaining the interrelationships among strength of ties, conflicts and project performance. Third, this study will respond to the call "which dimension, i.e. strong ties or weak ties, is more influential" by exploring the direct and indirect effects of strength of ties on project performance.

Particle emissions derived from construction activities have a significant impact on the local air quality, while the canyon effect with reduced natural ventilation contributes to the highest particulate pollution in urban environments. This study attempted to examine the effect of PM10 emissions derived from the construction of a rail transit system in an urban street canyon. Using a 3D computational fluid dynamic (CFD) model based on a real street canyon with different height ratios, this study formulates the impact of height ratio and wind directions on the dispersion and concentration of PM10. The results indicate that parallel flow would cause the concentration of PM10 at the end of the street canyons in all height ratios, and the trends in horizontal, vertical and lateral planes in all street canyons are similar. While in the condition of perpendicular flow, double-eddy circulations occur and lead to the concentration of PM10 in the middle part of the street canyon and leeward of backwind buildings in all height ratios. Furthermore, perpendicular flow will cause the concentration of PM10 to increase if the upwind buildings are higher than the backwind ones. This study also shows that the dispersion of PM10 is strongly associated with wind direction in and the height ratios of the street canyons. Certain measures could, therefore, be taken to prevent the impact on people in terms of the PM10 concentration and the heights of street canyons identified in this research. Potential mitigation strategies are suggested, include measurements below 4 m according to governmental regulations, dust shields, and atomized water.