National Chi Nan University

Three-dimensional (3D) bioprinting provides new options for airway reconstruction by enabling the fabrication of customizable, biodegradable scaffolds designed to support in situ tissue regeneration. Building on our established large-animal platform, in which two cm bioprinted tracheal grafts combined with refined surgical techniques and adjunctive laser intervention have achieved long-term survival exceeding three months, the present study aims to explore long-segment (≥four cm) tracheal transplantation. We evaluated the fabrication feasibility and regeneration patterns of extrusion-based 3D bioprinted polycaprolactone (PCL) tracheal grafts in a porcine model. The grafts were implanted via end-to-end anastomosis with adjunctive mechanical stabilization and followed by serial bronchoscopic surveillance, gross examination, and histological analysis. The two cm PCL tracheal grafts achieved reproducible survival exceeding three months when combined with refined surgical techniques, structured postoperative airway management, and optimized wound coverage. Histological analysis revealed multi-lineage tissue formation-including cartilage, muscle, glands, and epithelium-was observed. Cartilage regeneration followed a staged maturation process, compared to epithelial regeneration, although continuous by 12 weeks, remained developmentally immature. A single long-segment transplantation was explored in a single preliminary case, providing an initial technical observation of feasibility; however, definitive conclusions regarding long-term survival or regeneration cannot be drawn. These findings further characterize regenerative responses in a large-animal model and highlight critical translational barriers-fabrication constraints, airway biomechanics, and delayed epithelial maturation-that require systematic investigation before long-segment tracheal reconstruction can advance toward clinical application.

Abstract Grounded in self-determination theory, this chapter investigates the impact of work meaning on service innovation behavior among travel agency employees and explores the moderating influence of perceived organizational support. A survey was conducted across 30 travel agencies in Taiwan, yielding 337 valid responses. The proposed hypotheses were tested using multiple regression analysis. The analysis indicates that a strong sense of work meaning enhances employees’ service innovation behavior. Furthermore, perceived organizational support strengthens this relationship, suggesting that when employees recognize supportive actions from their organization, they are more prone to translate meaningful work into innovative service practices. These findings expand the existing theoretical knowledge of service innovation by emphasizing the psychological and organizational factors that drive it. Additionally, this chapter provides practical insights for travel agencies, highlighting the importance of fostering a meaningful work environment and organizational support to encourage innovation. Future research directions are also proposed to expand on these findings.

In this study, first-principles density functional theory (DFT) calculations were employed to investigate the effects of single and binary gas adsorption of NO, CO, CO2, NO2, H2S, and O3 on the ZnGa2O4(111) surface. For single-gas adsorption, O3 adsorbed on surface Ga sites induces a pronounced work-function increase of 0.97 eV, whereas H2S adsorption at surface O sites yields the strongest adsorption energy (-1.21 eV), highlighting their distinct electronic interactions with the surface. For binary co-adsorption, the NO2-O3 pair adsorbed at Ga-coordinated sites produces the largest work-function shift (1.88 eV), while adsorption at Zn sites results in the most stable configuration, with an adsorption energy reaching -3.98 eV. These results indicate that co-adsorption of highly electronegative gases can significantly enhance charge transfer and sensing response. In contrast, mixed oxidizing-reducing gas pairs, such as NO2-H2S, lead to a markedly suppressed work-function variation (-0.02 eV), suggesting reduced sensor sensitivity due to compensating charge-transfer effects. Overall, this work demonstrates that gas-sensing behavior on ZnGa2O4(111) is governed not only by individual gas-surface interactions but also by cooperative and competitive effects arising from binary co-adsorption, providing insights into realistic multi-gas sensing environments.

This study presents a one-step electrochemical etchingstrategythat enables the simultaneous formation of porous silicon (PSi) andin situ deposition of noble metal nanoparticles (NPs), which subsequentlyact as nucleation sites for gold growth to form bimetallic SERS substrates.Three metal precursorsK2PtCl4, HAuCl4, and K2PdCl4were systematicallycompared to elucidate how precursor type affects PSi morphology, nanoparticledistribution, and subsequent gold deposition. SEM and EDS analysesrevealed distinct deposition behaviors among the metals, leading tovaried gold nucleation efficiencies and SERS enhancement levels. HAuCl4-treated substrates produced the highest absolute Raman intensity,while K2PtCl4-treated substrates exhibited lowerintensity but superior spectral quality with minimal fluorescencebackground and sharper peaks. XRD and XPS confirmed successful golddeposition and precursor-dependent interfacial interactions, includingthe formation of Pt–Au bimetallic interfaces. Reusability testsdemonstrated that the Pt-assisted substrates maintained stable performanceover multiple cycles, confirming their structural robustness and practicalfeasibility. Overall, this work provides mechanistic insight intohow noble metal interfaces govern SERS spectral characteristics andestablishes a rational pathway for designing PSi-based SERS substratesemphasizing spectral precision, reproducibility, and reusability ratherthan mere sensitivity enhancement.

Hamiltonian cycle problems play a central role in graph theory and have wide-ranging applications in network-on-chip architectures, interconnection networks, and large-scale parallel systems. When a network contains faulty nodes or faulty links, the feasibility of certain paths becomes restricted, making the construction of Hamiltonian cycles substantially more difficult and increasingly important for ensuring reliable communication. A dimension-balanced Hamiltonian cycle is a special type of cycle that maintains an even distribution of edges across multiple dimensions of a network. Its directed counterpart extends this idea to symmetric directed networks by balancing the number of edges used in each positive and negative direction. Such cycles are desirable because they support uniform traffic distribution and reduce communication contention in practical systems. Previous research has examined the existence of directed dimension-balanced Hamiltonian cycles in directed toroidal mesh networks and has shown that some configurations permit directed dimension-balanced Hamiltonian cycles while others do not. Building on this foundation, this paper investigates the fault-tolerant properties of such networks by analyzing whether directed dimension-balanced Hamiltonian cycles still exist when a single vertex (node) or a single edge (link) is faulty. Our results extend the current understanding of Hamiltonian robustness in symmetric directed networks.