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11.
Real options analysis was often recommended as an emerging valuation technique for high-risk investment projects. Former inter-sectoral surveys have drawn an ambivalent picture of real options usage in general. In addition, there is a lack of sector-specific investigations. In the following article the results of an in-depth analysis of collected empirical data regarding the application of this new tool in the pharmaceutical sector is presented by capturing the internal view from the pharmaceutical companies themselves and the external view from the health care departments of financial service firms. R&D stage specific modi of application, reasons for reluctance in the employment of real options and their assumed future prospects are elucidated. 相似文献
12.
Dong-Dong Wu Cui-Ping Yang Ming-Shan Wang Kun-Zhe Dong Da-Wei Yan Zi-Qian Hao Song-Qing Fan Shu-Zhou Chu Qiu-Shuo Shen Li-Ping Jiang Yan Li Lin Zeng He-Qun Liu Hai-Bing Xie Yun-Fei Ma Xiao-Yan Kong Shu-Li Yang Xin-Xing Dong Ali Esmailizadeh David M Irwin Xiao Xiao Ming Li Yang Dong Wen Wang Peng Shi Hai-Peng Li Yue-Hui Ma Xiao Gou Yong-Bin Chen Ya-Ping Zhang 《国家科学评论(英文版)》2020,7(6):952
Abundant and diverse domestic mammals living on the Tibetan Plateau provide useful materials for investigating adaptive evolution and genetic convergence. Here, we used 327 genomes from horses, sheep, goats, cattle, pigs and dogs living at both high and low altitudes, including 73 genomes generated for this study, to disentangle the genetic mechanisms underlying local adaptation of domestic mammals. Although molecular convergence is comparatively rare at the DNA sequence level, we found convergent signature of positive selection at the gene level, particularly the EPAS1 gene in these Tibetan domestic mammals. We also reported a potential function in response to hypoxia for the gene C10orf67, which underwent positive selection in three of the domestic mammals. Our data provide an insight into adaptive evolution of high-altitude domestic mammals, and should facilitate the search for additional novel genes involved in the hypoxia response pathway. 相似文献
13.
Sajjad Rahmani Dabbagh Fazle Rabbi Zafer Doan Ali Kemal Yetisen Savas Tasoglu 《Biomicrofluidics》2020,14(6)
High-throughput, cost-effective, and portable devices can enhance the performance of point-of-care tests. Such devices are able to acquire images from samples at a high rate in combination with microfluidic chips in point-of-care applications. However, interpreting and analyzing the large amount of acquired data is not only a labor-intensive and time-consuming process, but also prone to the bias of the user and low accuracy. Integrating machine learning (ML) with the image acquisition capability of smartphones as well as increasing computing power could address the need for high-throughput, accurate, and automatized detection, data processing, and quantification of results. Here, ML-supported diagnostic technologies are presented. These technologies include quantification of colorimetric tests, classification of biological samples (cells and sperms), soft sensors, assay type detection, and recognition of the fluid properties. Challenges regarding the implementation of ML methods, including the required number of data points, image acquisition prerequisites, and execution of data-limited experiments are also discussed. 相似文献
14.
Ali Asghar Ghasemi Hooshang Yazdani Majid Amerian 《Journal of Intercultural Communication Research》2020,49(1):41-60
ABSTRACTThis study aimed to present a model of intercultural communicative competence (ICC) by incorporating international posture, motivational disposition (ideal L2 self), second language (L2) self-confidence, and metacognitive learning strategies. To this end, 150 Iranian L2 learners, selected through convenience sampling procedure, took part in the research. The findings of structural equation modelling revealed that the proposed model showed adequate fit to the data, implying that the model is appropriate in Iranian English as a foreign language (EFL) context. Also, the results indicated that learners with a high level of international posture are more likely to bridge the gap between their present and ideal selves. This was, additionally, argued that internationally oriented and ideally motivated learners become confident of their abilities to get engaged in interaction with L2 target communities. Furthermore, metacognitive learning strategies were found to be directly associated with ICC, implicating that the learners who continuously reflect on their learning and evaluate their performances are more prone to have a higher level of ICC. Finally, suggestions were offered for language teachers and policy-makers to inspire their learners to be more competent in communication with people of other cultures and languages. 相似文献
15.
Robert Dan Michael Cate A. Egan Lynda Nilges Ali Brian Robert Johnson 《Research quarterly for exercise and sport》2019,90(2):151-162
Purpose: A systematic review was conducted to identify facilitators and barriers to movement integration (MI) in elementary school classrooms. Method: Online databases (Educational Resources Information Center, Google Scholar, PsycINFO, and PubMed) served as data sources for the study. Following the PRISMA guidelines, relevant published research on MI was identified and screened for inclusion in a qualitative synthesis. Content analysis of the included articles (N = 28) was used to identify themes of MI facilitators and barriers. Facilitators and barriers were then categorized using a social-ecological framework. Results: A total of 12 themes of MI facilitators and barriers were identified and categorized into two social-ecological levels: institutional factors (e.g., administrative support, resources) and intrapersonal factors (e.g., teacher confidence, ease of implementation). Conclusion: This review can inform research and practice aimed at supporting the implementation of MI in elementary classrooms. 相似文献
16.
17.
Fatma Emel Kocak Bahadir Ozturk Ozben Ozden Isiklar Ozlem Genc Ali Unlu Irfan Altuntas 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):430-438
Introduction
Total 25-hydroxyvitamin D [25(OH)D] is the most reliable indicator of vitamin D status. In this study, we compared two automated immunoassay methods, the Abbott Architect 25-OH Vitamin D assay and the Roche Cobas Vitamin D total assay, with the liquid chromatography-tandem mass spectrometry (LC-MS/MS).Materials and methods
One hundred venous blood samples were randomly selected from routine vitamin D tests. Two of the serum aliquots were analyzed at the Abbott Architect i2000 and the Roche Cobas 6000’s module e601 in our laboratory within the same day. The other serum aliquots were analyzed at the LC-MS/MS in different laboratory. Passing-Bablok regression analysis and Bland-Altman plot were used to compare methods. Inter-rater agreement was analyzed using kappa (κ) analysis.Results
The Roche assay showed acceptable agreement with the LC-MS/MS based on Passing-Bablok analysis (intercept: -5.23 nmol/L, 95% CI: -8.73 to 0.19; slope: 0.97, 95% CI: 0.77 to 1.15). The Abbott assay showed proportional (slope: 0.77, 95% CI: 0.67 to 0.85) and constant differences (intercept: 17.08 nmol/L; 95% CI: 12.98 to 21.39). A mean bias of 15.1% was observed for the Abbott and a mean bias of -14.1% was observed for the Roche based on the Bland-Altman plots. We found strong to nearly perfect agreement in vitamin D status between the immunoassays and LC-MS/MS. (κ: 0.83 for Abbott, κ: 0.93 for Roche) using kappa analysis.Conclusion
Both immunoassays demonstrated acceptable performance, but the Roche Cobas assay demonstrated better performance than the Abbott Architect in the studied samples.Key words: 25-Hydroxyvitamin D, chromatography, immunoassay, methods, tandem mass spectrometry 相似文献18.
We introduce a new model for contact angle saturation phenomenon in electrowetting on dielectric systems. This new model attributes contact angle saturation to repulsion between trapped charges on the cap and base surfaces of the droplet in the vicinity of the three-phase contact line, which prevents these surfaces from converging during contact angle reduction. This repulsion-based saturation is similar to repulsion between charges accumulated on the surfaces of conducting droplets which causes the well known Coulombic fission and Taylor cone formation phenomena. In our model, both the droplet and dielectric coating were treated as lossy dielectric media (i.e., having finite electrical conductivities and permittivities) contrary to the more common assumption of a perfectly conducting droplet and perfectly insulating dielectric. We used theoretical analysis and numerical simulations to find actual charge distribution on droplet surface, calculate repulsion energy, and minimize energy of the total system as a function of droplet contact angle. Resulting saturation curves were in good agreement with previously reported experimental results. We used this proposed model to predict effect of changing liquid properties, such as electrical conductivity, and system parameters, such as thickness of the dielectric layer, on the saturation angle, which also matched experimental results. 相似文献
19.
Identity: a complex structure for researching students’ academic behavior in science and mathematics
This article is a response to Pike and Dunne’s research. The focus of their analysis is on reflections of studying science
post-16. Pike and Dunne draw attention to under enrollments in science, technology, engineering, and mathematics (STEM) fields,
in particular, in the field of physics, chemistry and biology in the United Kingdom. We provide an analysis of how the authors
conceptualize the problem of scientific career choices, the theoretical framework through which they study the problem, and
the methodology they use to collect and analyze data. In addition, we examine the perspective they provide in light of new
developments in the field of students’ attitudes towards science and mathematics. More precisely, we draw attention to and
explicate the authors’ use of identity from the perspective of emerging theories that explore the relationships between the
learner and culture in the context of science and mathematics. 相似文献
20.
新时期柯尔克孜族小说集《黑脸山仙》以立足现实、反映民族生活的现实主义精神,超越民族地域界限的世界性因素,以及鲜明的民族地域特色与现代表现手段相结合的特点,展示了新时期柯尔克孜小说的成就及成长历程。 相似文献