25 research outputs found
Predicting Problem-Solving Performance Using Concept Map
A growing community of researchers applies the concept map for elicitation and representation individualâs knowledge structure especially within knowledge-intensive processes in organizations. As an extension of prior works on concept map, this study aims to explore a new indicator of structural properties of concept map from an information entropy perspective to predict an individualâs problem-solving performance. From the information processing view of problem-solving, Information Theory provides the framework to formulate a new indicator called EntropyAvg. A controlled experiment was carried out to validate the predictive ability of the new indicator. The results demonstrate that EntropyAvg is able to estimate an individualâs problem-solving performance beyond two other widely adopted indicators, i.e., complexity and integration. The theoretical and practical contributions of this study are also discusse
A dramatic, objective antiandrogen withdrawal response: case report and review of the literature
Antiandrogen withdrawal response is an increasingly recognized entity in patients with metastatic prostate cancer. To our knowledge, there have been no reports describing a durable radiologic improvement along with prostate-specific antigen (PSA) with discontinuation of the antiandrogen agent bicalutamide. We report a case in which a dramatic decline of serum PSA levels associated with a dramatic improvement in radiologic disease was achieved with bicalutamide discontinuation
China
Economic development processes in post-1949 China can be divided into two periods. In the first, 1950-70, the economy was extensively and intensively controlled by the state with a priority for developing heavy industries. In the second, since the 80s and known as the \u27reform period,\u27 the Chinese economy has increasingly been integrated with the world economy and relying on light (rural) industries as the prime motor of economic growth. Yet, in both these periods, Chinese policymakers shared the same \u27developmental\u27 philosophy in which social costs, that is the reproduction costs of human labour and nature, are largely ignored. The following is a critical sketch of government policies and their impact on the domestic population in these two periods
Consumersâ Sentiments and Popularity of Brand Posts in Social Media: The Moderating Role of Up-votes
User-generated contents (UGC) on online social media plays an important role in the branding and marketing of firmsâ products and services. In this study, we examine the effect of consumersâ sentiments embedded in UGC on the popularity of brand posts. We retrieved real-world data from a social media platform and utilized a rigorous data analysis method that exploited state-of-the-art semi-supervised sentiment analysis technique. Our empirical findings confirm that positive and negative sentiments are associated with post popularity to some extent. Also, the customersâ up-votes for negative comments somehow moderates the effect of negative comments on post popularity. To the best of our knowledge, this is the first study that demonstrates the specific role of up-votes in enhancing the popularity of brand posts on online social media. Our findings provide a promising theoretical contribution to the literature. The managerial implication is that firms can apply our findings to develop more effective strategies for marketing through social media brand communities
A first-in-human phase 1 study of a hepcidin monoclonal antibody, LY2787106, in cancer-associated anemia
Belief revision for adaptive information agents
As the richness and diversity of information available to us in our everyday lives has expanded, so the need to manage this information grows. The lack of effective information management tools has given rise to what is colloquially known as the information overload problem. Intelligent agent technologies have been explored to develop personalised tools for autonomous information retrieval (IR). However, these so-called adaptive information agents are still primitive in terms of their learning autonomy, inference power, and explanatory capabilities. For instance, users often need to provide large amounts of direct relevance feedback to train the agents before these agents can acquire the users' specific information requirements. Existing information agents are also weak in dealing with the serendipity issue in IR because they cannot infer document relevance with respect to the possibly related IR contexts. This thesis exploits the theories and technologies from the fields of Information Retrieval (IR), Symbolic Artificial Intelligence and Intelligent Agents for the development of the next generation of adaptive information agents to alleviate the problem of information overload. In particular, the fundamental issues such as representation, learning, and classjfication (e.g., classifying documents as relevant or not) pertaining to these agents are examined. The design of the adaptive information agent model stems from a basic intuition in IR. By way of illustration, given the retrieval context involving a science student, and a query "Java", what information items should an intelligent information agent recommend to its user? The agent should recommend documents about "Computer Programming" if it believes that its user is a computer science student and every computer science student needs to learn programming. However, if the agent later discovers that its user is studying "volcanology", and the agent also believes that volcanists are interested in the volcanos in Java, the agent may recommend documents about "Merapi" (a volcano in Java with a recent eruption in 1994). This scenario illustrates that a retrieval context is not only about a set of terms and their frequencies but also the relationships among terms (e.g., java ? science ? computer, computer ? programming, java ? science ? volcanology ? merapi, etc.) In addition, retrieval contexts represented in information agents should be revised in accordance with the changing information requirements of the users. Therefore, to enhance the adaptive and proactive IR behaviour of information agents, an expressive representation language is needed to represent complex retrieval contexts and an effective learning mechanism is required to revise the agents' beliefs about the changing retrieval contexts. Moreover, a sound reasoning mechanism is essential for information agents to infer document relevance with respect to some retrieval contexts to enhance their proactiveness and learning autonomy. The theory of belief revision advocated by AlchourrĂłn, GĂ€rdenfors, and Makinson (AGM) provides a rigorous formal foundation to model evolving retrieval contexts in terms of changing epistemic states in adaptive information agents. The expressive power of the AGM framework allows sufficient details of retrieval contexts to be captured. Moreover, the AGM framework enforces the principles of minimal and consistent belief changes. These principles coincide with the requirements of modelling changing information retrieval contexts. The AGM belief revision logic has a close connection with the Logical Uncertainty Principle which describes the fundamental approach for logic-based IR models. Accordingly, the AGM belief functions are applied to develop the learning components of adaptive information agents. Expectationinference which is characterised by axioms leading to conservatively monotonic IR behaviour plays a significant role in developing the agents' classification components. Because of the direct connection between the AGM belief functions and the expectation inference relations, seamless integration of the information agents' learning and classification components is made possible. Essentially, the learning functions and the classification functions of adaptive information agents are conceptualised by and q d respectively. This conceptualisation can be interpreted as: (1) learning is the process of revising the representation K of a retrieval context with respect to a user's relevance feedback q which can be seen as a refined query; (2) classification is the process of determining the degree of relevance of a document d with respect to the refined query q given the agent's expectation (i.e., beliefs) K about the retrieval context. At the computational level, how to induce epistemic entrenchment which defines the AGM belief functions, and how to implement the AGM belief functions by means of an effective and efficient computational algorithm are among the core research issues addressed. Automated methods of discovering context sensitive term associations such as (computer ? programming) and preclusion relations such as (volcanology /? programming) are explored. In addition, an effective classification method which is underpinned by expectation inference is developed for adaptive information agents. Last but not least, quantitative evaluations, which are based on well-known IR bench-marking processes, are applied to examine the performance of the prototype agent system. The performance of the belief revision based information agent system is compared with that of a vector space based agent system and other adaptive information filtering systems participated in TREC-7. As a whole, encouraging results are obtained from our initial experiments
Emodin, a tyrosine kinase inhibitor, and human cancer
Many human diseases, including cancers, result from aberrations of signal transduction pathways. The recent understanding of the molecular biochemistry of signal transduction in normal and transformed cells enable us to have a better insight about cancer and design new drugs to target this abnormal signaling in the cancer cells. Tyrosine kinase pathway plays a very important role in normal and cancer cells. Enhanced activity of tyrosine kinases has been associated with many human cancer types. Therefore, identifying the type of tyrosine kinases involved in a particular cancer type and blocking these tyrosine kinase pathways may provide a way to treat cancer. Receptor tyrosine kinase expression, namely epidermal growth factor receptor (EGFR) family, was examined in the oral squamous cell carcinoma patients. The expression levels of different members of the EGFR family were found to be significantly associated with shorter patients\u27 survival. Combining EGFR, HER-2/neu, and HER-3 expression can significantly improve the predicting power. The effect of emodin, a tyrosine kinase inhibitor, on these receptors in head and neck squamous cell carcinoma cell lines was examined. Emodin was found to suppress the tyrosine phosphorylation of HER-2/neu and EGF-induced tyrosine phosphorylation of EGFR. Emodin also induced apoptosis and downregulated the expression of anti-apoptotic protein bcl-2 in oral squamous cell carcinoma cells. It is known that tyrosine kinase pathways are involved in estrogen receptor signaling pathway. Therefore, the effects of inhibiting the tyrosine kinase pathway in estrogen receptor-positive breast cancers was studied. Emodin was found to act similarly to antiestrogens, capable of inhibiting estrogen-stimulated growth and DNA synthesis, and the phosphorylation of Rb protein. Interestingly, emodin, and other tyrosine kinase inhibitors, such as RG 13022 and genistein, depleted cellular levels of estrogen receptor protein. Emodin-induced depletion of estrogen receptor was mediated by the proteasome degradation pathway. In summary, we have demonstrated that tyrosine kinase pathways play an important role in oral squamous cell carcinoma and estrogen receptor-positive breast cancer. Targeting the tyrosine kinases by inhibitors, such as emodin, may provide a potential way to treat the cancer patients
Is There a Relationship between Social Executives and Firms\u27 Mergers and Acquisition Decisions: An Empirical Study Based on Twitter
This study examines the relationship between senior executivesâ presence on online social media and mergers and acquisitions (M&A) decisions. Our empirical results derived from the difference-in-difference analysis suggest that the presence of social executives on social media improves M&A decisions (likelihood and frequency). Interestingly, we find that executive age negatively moderates this relationship such that younger social executives are more likely to undertake M&As than their older peers
ExeAnalyzer: A Deep Generative Adversarial Network for Multimodal Online Impression Analysis and Startup Funding Prediction
With the rise of equity crowdfunding platforms, entrepreneurs\u27 online impressions are of great importance to startups\u27 initial funding success. Guided by the design science research methodology, one contribution of our research is to design a novel Generative Adversarial Network, namely ExeAnalyzer, to analyze CEOs\u27 online impressions by using multimodal data collected from social media platforms. More specifically, ExeAnalyzer can detect CEOs\u27 first impressions, personalities, and other sociometric attributes. Based on a dataset of 7,806 startups extracted from AngelList, another contribution of our research is the empirical analysis of the relationship between CEOs\u27 online impressions and startups\u27 funding successes. Our empirical analysis shows that CEOs\u27 impression of dominance is negatively related to startups\u27 funding performance, while the social desirability of CEOs is positively associated with startups\u27 funding success. Our empirical study also confirms that the impression features extracted by ExeAnalyzer have significant predictive power on startups\u27 funding performance