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As the leading urban agglomeration in China, the Yangtze River Delta (YRD) is experiencing a factor-driven to innovation-driven transition. However, the dynamics of regional innovation growth are not yet fully understood. This paper combines the complex network methodology with spatial econometrics to disentangle the contributions of innovation endowments, innovation network flows, and innovation network positions to regional innovation growth, as well as their spatial spillover effects. The primary findings suggest that regional innovation growth results from the networked agglomeration economies, which is shaped by the interactions between agglomeration factors and network factors. Specifically, agglomeration factors play a fundamental role in regional innovation growth. In contrast, network factors, such as the network flows and network positions, may contribute to new path creation by promoting access to external innovation resources. Additionally, the institutional factors show multiplexity in fostering regional innovation patterns. Such findings indicate that the YRD region should shift the innovation growth pattern from competitive involution to mutually beneficial cooperation to reduce regional disparities. In this regard, the institutional capacity of organizing network flows and fostering reciprocal inter-city partnerships has become increasingly critical for promoting sustainable innovation and regional development. [ABSTRACT FROM AUTHOR]

The leave-one-out cross-validation is an important parameter selection strategy for SVM-like family, including SVM and SVR. However, due to the high computational complexity, the adaptability of this strategy is restricted. In this paper, aiming at its practical application, a fast leave-one-out cross-validation method by using an adjustment factor is proposed which focusses especially on the practicability for the SVM-like family where the decision function can be expressed by explicit dot-product of each training sample pair. The ability of the proposed method in fast parameter selection is better than that of original leave-one-out cross-validation with the same or comparable learning performance. The simulation results indicate the effectiveness and speedup of the proposed leave-one-out cross-validation method. [ABSTRACT FROM AUTHOR]

Previous designs of conventional aerodynamic lens have been widely used to focus large nanoparticles. It is a big challenge to focus small sub-10 nm nanoparticles. The focusing of small nanoparticle is controlled by two factors: high diffusivity and low inertia. Here, we made some modification for the aerodynamic lens system designed by Wang et al. (Aerosol Sci Technol 39:624, 1). The capability of focusing sub-10 nm nanoparticles was evaluated by the computational fluid dynamics software FLUENT. From numerical simulations of size-resolved particle trajectories, it was found that most of the small nanoparticles lost to the wall by diffusion. The effect of Brownian diffusion on the particle extraction from lens system is investigated. Simulations have shown that the Brownian diffusion perturbs the trajectories of nanoparticles that are dictated by the carrier gas and increase the probability of nanoparticle deposition on the wall. The effect of lens system geometry on the nanoparticles is also investigated. The results of simulation showed that the geometry of lens system affected the beam diameter and the transmission efficiency of nanoparticle. [ABSTRACT FROM AUTHOR]

Purpose: Colonic perforation is a life-threatening complication after colonic stent insertion as a bridge to surgery for acute obstruction caused by colorectal cancer. The oncological consequence of colonic perforation after emergent surgical intervention was unknown. The aim of this short communication was to investigate whether or not the perforation and emergent surgery had obviously impact on the peritoneal recurrence and long-term survival of patients. Methods: Data of the patients who underwent colorectal stenting as a bridge to surgery in 5 years from 2012 to 2017 was collected by the Endoscopical Surgery Group of Hubei. The perforated cases treated by emergent operation were retrospectively analyzed. Results: During 5 years from 2012 to 2017, 116 cases of colorectal stenting as a bridge to surgery had been performed, and 7 patients had perforation after stent placement and treated by emergent surgery, including 1 case of synchronic liver metastasis treated by one-stage metastasectomy. One of the 7 patients died of septic shock after operation, and the remaining patients were followed up for 6–60 months. There was no evidence of abdominal implantation or extra-abdominal metastasis. Conclusion: This small case series implicated that colonic perforation after stent insertion for malignant colorectal obstruction treated by emergent surgery might not obviously increase the peritoneal implantation and metastasis. [ABSTRACT FROM AUTHOR]