R&D Investment Strategies of Firms: Renewal or Abandonment. A Real Options Perspective

This research develops a real options perspective framework for firms‘ valuation of strategic investments. I propose that a real options perspective can provide an effective means of re-examining and revising firms‘ strategic investment decisions in general, and of making individual, investment-level abandonment decisions in particular. The principal purposes of this research are to explore whether firms make abandonment decisions in accordance with real options theory, and the relative strength of the traditional economic theory, the behavioral theory of the firm and real options theory in explaining firms‘ abandonment decisions. I develop a set of hypotheses in the context of firms‘ R&D investment strategies in the world chemical industry. Using U.S. patent renewal data, I empirically test the hypotheses. The results from the empirical analyses suggest that, 1) firms‘ actual innovation abandonment decisions are consistent with the predictions made from real options theory; and 2) a real options perspective provides better explanation of firms‘ abandonment decisions than traditional economic theory and the behavioral theory of the firm. Therefore, taking such a perspective allows us to better predict abandonment than the other models. In investigating whether insights from real options theory enlighten firm‘s abandonment decisions, this research contributes to the strategic decision making literature, real options research, RBV and dynamic capability research and innovation literature

The Challenges of E-Commerce Implementation for Saudi SMEs: Case Study of Retail Sector in Riyadh

With the rapid growth of information globalization, e-commerce has been increasingly popular in the last decade. For developing countries, e-commerce plays an instrumental role in gaining more benefit from trade. Therefore, e-commerce would help developing economies to obtain a solid foothold in the multilateral trading system. The service of e-commerce also would enhance the effectiveness and efficiency in the business domain and enables cost-reduction measures on commercial expenditure. This research focuses on the e-commerce adoption for small and medium-sized enterprises (SMEs) in Saudi Arabia. The objective of this study is to identify realistic challenges and barriers of implementing e-commerce in Saudi Arabia. The collection of primary data was from 153 SMEs of retail sector in Riyadh, based on purposive sampling technique. Secondary data from previous academic studies was deployed for this research as well. After the analysis of received data, six key barriers of e-commerce implementation for Saudi SMEs were identified: Cost of Launching an E-commerce Venture; Cultural Influences; Lack of Professionals; Incomplete Logistics Distribution Systems; Imperfect Information and Communication Technology; Fear of Risk Taking and Failure. This is 26.14%, 24.84%, 16.34%, 13.73%, 12.42% and 6.53% of the research sample respectively. Keywords: e-commerce, small and medium-sized enterprises, Saudi Arabia, challenges and barrier

UNDERSTANDING STUDENT ENGAGEMENT AND LEARNING OUTCOMES: THE ROLE OF LEARNING STYLES

Despite extensive research on the influence of student engagement in the classroom on student learning outcomes, few studies have examined student learning styles and their engagement in learning activities. In this research-in-progress paper, we propose a research model to examine whether student engagement during role-play exercises will lead to better learning and satisfaction, and the role learning style plays in influencing engagement. We conducted a survey study to evaluate our research model. Preliminary results show partial support for our research model. Our research will make contributions to the theoretical understanding of the relationships between engagement, learning styles and learning outcomes. Our study will also provide practical guidance for instructors to design instructional activities that accommodate for individual learning style differences

Exploring the Relationship Among Learning Styles, Engagement, and Learning Outcomes in the Context of Role-Play Activities

This study proposes a research model to examine whether student engagement during role-play exercises leads to better learning and satisfaction, as well as the influence learning styles have on engagement. Our results confirm that engagement is a multifaceted construct, and show that learning styles affect the dimensions of engagement differently. The effects of each dimension of engagement on student learning and satisfaction also vary. Our research contributes to the theoretical understanding of the relationships among engagement, learning styles, and learning outcomes. Our study also provides practical guidance on how to design instructional activities that accommodate differences in individual learning styles

Steering of magnetotactic bacterial microrobots by focusing magnetic field for targeted pathogen killing

International audienceTargeted steering of magnetotactic bacterial microrobots is a growing tendency for their various biomedical applications. However, real-time monitoring during their movements and targeted cell killing in specific locations remains challenging. Here, we steered bacterial microrobots to target and attach to Staphylococcus aureus that was subsequently killed in a magnetic target device, which can realize guiding, mixing, and killing for targeted therapy. The generated focusing magnetic field was applied to magnetotactic bacterial microrobots, and the realizability of control strategies was analyzed. We successfully guided magnetotactic bacterial microrobots in microfluidic chips without real-time monitoring of their location. After mixing with microrobots under a rotating magnetic field for their attachment, the pathogen was killed under a swinging magnetic field. These results suggest that targeted therapy with these microrobots by using a magnetic target device is a promising approach

Analysis on Causes of Large-scale Ordovician Karst Water Inrush at 27080 Working Face of Eastern Caoyao Mine

The large-scale Ordovician Karst water inrush occurred at 27080 working face in Caoyao Eastern Mine on December 23th, 2006, the maximum water inflow arrived at 1693 cubic meters per hour. The source of this water inrush was the Ordovician karst water; the dynamic condition was high hydraulic pressure; the water conducted channels were formed by hydraulic pressure and rock pressure in the weak area of floor; and the space of that was offered by excavation. The proposals for preventing and controlling water were put forward.特集 : 「資源、新エネルギー、環境、防災研究国際セミナー

ZnCdS Dotted with Highly Dispersed Pt Supported on SiO2 Nanospheres Promoting Photocatalytic Hydrogen Evolution

[EN] The efficiency of solar hydrogen evolution closely depends on the fast transfer of charge carriers and the effective use of visible light. In this work, a novel photocatalyst SiO2/ZnCdS/Pt was successfully prepared to solve these two problems. An artistic structure of the photocatalyst was constructed and ZnCdS was successfully wrapped on the surface of SiO2 spheres with uniform Pt nanoparticles (NPs) in a size of 4.1 +/- 0.7 nm highly dispersed on the ZnCdS shell through the self-assembly method. Pt NPs can absorb the scattered light in the near field of SiO2 spheres. With the synergistic effect of SiO2 spheres and small highly dispersed Pt NPs, the absorption of visible light was significantly promoted. Meanwhile, the electron-hole recombination was also effectively inhibited, thus improving the photocatalytic activity. The hydrogen production activity of the highly efficient photocatalyst was as high as 8.3 mmol g(-1) h(-1) under visible light (lambda > 420 nm). The photocatalytic activity of SiO2/ZnCdS/Pt was 2.9 times higher than that of the ZnCdS/Pt photocatalyst.This work was supported by the National Natural Science Foundation of China (21976111), Shandong Provincial Natural Science Foundation (ZR2019MB052), and Large Instrument Open Foundation of Shandong Normal University (KFJJ2019004; KFJJ2021006).Liu, K.; Peng, L.; Zhen, P.; Chen, L.; Song, S.; García Gómez, H.; Sun, C. (2021). ZnCdS Dotted with Highly Dispersed Pt Supported on SiO2 Nanospheres Promoting Photocatalytic Hydrogen Evolution. The Journal of Physical Chemistry C. 125(27):14656-14665. https://doi.org/10.1021/acs.jpcc.1c0353514656146651252

Correlation between tongue manifestations and glucose, total cholesterol, and high-density lipoprotein cholesterol in patients with acute cerebral infarction

AbstractObjectiveTo analyze the association between tongue manifestations and the levels of glucose (GLU), total cholesterol (TCH), and high-density lipoprotein cholesterol (HDL-C) in subjects with acute cerebral infarction.MethodsHospitalized patients with first unilateral cerebral infarction in the Neurological Department of Xuanwu Hospital were included and the correlation between tongue fur color, fur nature, and the levels of GLU, TCH, HDL-C were analyzed.ResultsHDL level in the thin fur group was higher than that in the thick fur group (P=0.02). The difference in the levels of GLU, TCH, and HDL-C among the groups was significant (P<0.05), classified in terms of slippery, moist, and dry fur. Further comparison between the groups by Student-Newman-Keuls test showed that GLU level in the dry fur group was the highest. Moreover, the TCH level in the slippery fur group was higher than the other two groups.ConclusionA correlation between tongue manifestations and GLU, TCH, HDL-C was identified in the patients with acute cerebral infarction