Ordering-sensitive and Semantic-aware Topic Modeling

Topic modeling of textual corpora is an important and challenging problem. In most previous work, the "bag-of-words" assumption is usually made which ignores the ordering of words. This assumption simplifies the computation, but it unrealistically loses the ordering information and the semantic of words in the context. In this paper, we present a Gaussian Mixture Neural Topic Model (GMNTM) which incorporates both the ordering of words and the semantic meaning of sentences into topic modeling. Specifically, we represent each topic as a cluster of multi-dimensional vectors and embed the corpus into a collection of vectors generated by the Gaussian mixture model. Each word is affected not only by its topic, but also by the embedding vector of its surrounding words and the context. The Gaussian mixture components and the topic of documents, sentences and words can be learnt jointly. Extensive experiments show that our model can learn better topics and more accurate word distributions for each topic. Quantitatively, comparing to state-of-the-art topic modeling approaches, GMNTM obtains significantly better performance in terms of perplexity, retrieval accuracy and classification accuracy.Comment: To appear in proceedings of AAAI 201

Bedeutung von Akt2 und SGK1 bei der Regulation von Dendritischen Zellen

The present study investigates the role of Phosphoinositide 3 kinase (PI3K) pathway in the regulation of dendritic cell (DC) functions. DCs are antigen-presenting cells that provide a link between innate and adaptive immunity and are required for initiation of specific T cell-driven immune responses. The present project concentrates on the possible regulation of DC functions by two PI3K-dependent kinases, Akt2; and serum- and glucocorticoid-inducible kinase-1 (SGK1), which share 55% identity in their kinase domain regions. Akt 2; is known to be required for macrophage and DC migration, though the involved mechanisms remained undefined. On the other hand, DC migration is governed by Ca2+ signaling. In the present study, we addressed the mechanisms of Akt2-dependent DC migration by studying the possible involvement of Akt2 in Ca2+ signaling. In conclusion, Akt2 upregulates IP3R2 transcription in DCs, presumably by enhancing the expression of ETS1 and this effect may underlie the stimulating effect of Akt2 on DC migration. On the other hand, PI3K activation suppresses proinflammatory cytokine production in DCs, which limits excessive T helper (Th1) polarization. Little is known about the mechanisms of PI3K-mediated suppression in DCs. The present study explored whether SGK1 can act as a negative regulator of DC functions downstream from PI3K. These observations point to an important role of SGK1 in the regulation of DC functions and thus disclose a novel element in the cross-talk between innate and adaptive immunity. Impaired phosphorylation of NDRG-1 in SGK1-deficient DCs may underlie enhanced nuclear localization of NF-k;B and, accordingly, increased maturation and IL-12 production.In der vorliegenden Studie wurde die Rolle des Phosphoinositol 3 Kinase (PI3K) Signalweges in der Regulation der Funktion Dendritischer Zellen untersucht. Dendritische Zellen sind Antigen-präsentierende Zellen, welche einen Link zwischen angeborener und adaptiver Immunität herstellen und für die Aktivierung von spezifischen T-Zellen erforderlich sind. Das gegenwärtige Projekt konzentriert sich auf die mögliche Regulation der Dendritischen Zellfunktion durch zwei PI3K-abhängige Kinasen, Akt2; und die Serum- und Glukokortikoid-induzierbare Kinase-1 (SGK1), welche 55% identische Kinasedomänenregion besitzen. Einerseits ist es bekannt, dass Akt2; für Makrophagen und für die Migration Dendritischer Zellen erforderlich ist. Jedoch ist der involvierte Mechanismus noch weitgehend unerforscht. Andererseits wird die Migration Dendritischer Zellen vom Ca2+ Signalweg: reguliert. Zusammenfassend kann man sagen, dass Akt2 die IP3R2 Transkription in Dendritischen Zellen hochreguliert. Dies geschieht wahrscheinlich über eine Erhöhung der ETS1 Expression, wobei es wahrscheinlich zu einem stimulierenden Effekt von Akt2 auf die Migration Dendritischer Zellen führt. Die Aktivität von PI3K hemmt die Produktion von proinflammatorischen Zytokinen in Dendritischen Zellen. Diese Hemmung wirkt limitierend auf die übermäßige T-Helfer (Th1) Polarisation. Wenig ist über den Mechanismus der PI3K-vermittelten Unterdrückung in Dendritischen Zellen bekannt. In der vorliegenden Studie soll untersucht werden, ob SGK1 als ein negativer Regulator in der Funktion Dendritischer Zellen, der PI3K nachgeschaltet, fungiert. Diese Untersuchungen weisen auf eine wichtige Rolle von SGK1 in der Regulation der Funktion Dendritischer Zellen hin. Dies zeigt auf, dass SGK1 ein wichtiges Element in der Vernetzung zwischen angeborener und adaptiver Immunität ist. Eine erhöhte Phosphorylierung von NDRG-1 in SGK1 defizienten Dendritischen Zellen führt wahrscheinlich zu einer nukleären Lokalisation von NF-kB und im Anschluss zu einer erhöhten Reifung und IL-12 Produktion Dendritischer Zellen

Developing musical skills within ensemble environments : a qualitative case study of two community instrumental ensembles in Christchurch.

This thesis explores musical skill development in community music ensembles. It reveals how participation in such ensembles can contribute to the gaining or strengthening of musical skills and investigates what strategies are used to develop those skills, as well as how players conceptualise their musical experience. Through close observation of two local amateur instrumental ensembles, the Christchurch Accordion Orchestra and the Nor’West Brass Band, the above questions were explored within a methodological framework of the qualitative and collective case study. Video observations of the ensemble rehearsals and VSR-prompted semi-structured focus group interviews were employed as data collection methods. The software was used to generate VSR materials, analyse and code data gathered via both methods, and Interpretative Phenomenological Analysis was also adopted as an analytical approach. The research revealed a large variety of musical skills that were used and can be potentially developed or further improved in the rehearsal setting of community music ensembles. The learning opportunities ranged across technical skills, ensemble skills, music literacy skills, and musical and interpretational development. A broad range of strategies was implemented to support such skill development, including the conductor’s verbal, vocal and gestural feedback and some player-initiated strategies. Through frequent use of verbatim quotations, the study also indicated ensemble players’ conceptualisations of this ensemble experience, ranging from how they viewed their learning to the social experience itself. The findings of the thesis contribute to the research field of non-formal music education, specifically, knowledge about the experiences and musical learning gained through participation in community-based music ensembles. By providing further insights into the many educational opportunities offered through such communal music-making activity, a more thorough understanding of this activity is achieved, and the multifaceted nature is revealed. Finally, a series of suggestions are offered for community music practice and future research

Chinese Intellectuals and China\u27s Policy Toward Japan

This dissertation aims at integrating two scholarships: state-society relation studies and Chinese foreign policy analysis. I created Two-level Perception Gap Model to analyze different intellectual groups\u27 relations with party-state by confirming Chinese intellectuals play a role in CFP making in general, China\u27s Japan policy in particular. This model is an alternative approach, instead of conventional wisdom patron-client approach, to explain and analyze the pluralized intellectual-state relations in China. This model first analyzed the role of two intellectual groups, namely think tank scholars and popular nationalist, in China\u27s Japan policy making, and then based on these analyses it explains the interactional patterns between these two intellectual groups and party-state. I used three case studies, which represented different types of issue, Chinese attitude toward the U.S.-Japan alliance and the Japanese defense policy, the controversy over the Yasukuni Shrine Visit, and the territorial dispute over the Diaoyu/Senkaku Islands, to examine this model. First, I examined think tank scholar groups and the extent they influenced core interest issue and sensitive issue (Issue 1), Chinese attitude toward the U.S.-Japan alliance and the Japanese defense policy, and their international patterns with party-state. Chapter 3 compares the responses of Chinese officials to the changes in the defense policy of Japan to the analyses from the think tank scholars. As the model assumes, results show that think tank scholars\u27 analyses are consistent with China\u27s policy position; nevertheless, it is difficult to confirm their analyses have influence on Chinese attitude toward the U.S.-Japan alliance and the Japanese defense policy. Based on the analysis of journal articles, most articles do not provide policy suggestions or simply provide suggestions that do not deviate from the policy. As Gu\u27s theory of pluralist institutionalism and my hypothesis points out, most think tank scholars are establishment intellectuals so they tend to be self-disciplined. Second, this model provide a new concept patriotic dilemma for analyzing the challenge and constraints brought by popular nationalist discourses and public mobilization to Chinese foreign policy decision makers. Chapter 4 investigated the cases study of the controversy over the Yasukuni Shrine Visit, defined as major/minor interest issue/ sensitive issue (Issue 3), and the discourses from the popular nationalist, mainly focusing on anti-Japanese activists. The chapter also observes their influence on nationalist public opinions and analyzes how the nationalist public opinions constrain the policy choices among decision makers. Results strongly supported the hypothesis of patriotic dilemma that, although the popular nationalist group and public opinions constrained the policy choices of Chinese decision makers in the short term, they were unable to change the fundamental policy direction. Third, chapter 5 also focuses on anti-Japanese activists and examines the model with the case of the territorial dispute over the Diaoyu/Senkaku Islands. The result supported that hypothesis that China\u27s policy change was not because of the influence from popular nationalist\u27s discourses or public opinions but because of the change of priority of this issue, from major/minor interest issue to core interest issue. These two chapters also indicate that the patron-client model is unable to describe the popular nationalist. An alternative approach, such as the concept patriotic dilemma is needed to describe the relations between the popular nationalist and the government

Negative emotion under haze: an investigation based on the microblog and weather records of Tianjin, China

Nowadays, many big cities are suffering from heavy air pollution and continuous haze weather. Compared with the threat on physical health, the influence of haze on people’s mental health is much less discussed in the current literature. Emotion is one of the most important indicators of mental health. To understand the negative impact of haze weather on the emotion of the people, we conducted an investigation based on historical weather records and microblog data in Tianjin, China. Specifically, an emotional thesaurus was generated with a microblog corpus collected from sample data. Based on the thesaurus, the public emotion under haze was statistically described. Then, through correlation analysis and comparative study, the relation and seasonal variation of haze and negative emotion of the public were well discussed. According to the study results, there was indeed a correlation between haze and negative emotion of the public, but the strength of this relationship varied under different conditions. The level of air pollution and weather context were both important factors that influence the mental effects of haze, and diverse patterns of negative emotion expression were demonstrated in different seasons of a year. Finally, for the benefit of people’s mental health under haze, recommendations were given for haze control from the side of government

Study on e-government services quality: the integration of online and offline services

Purpose: E-Government, as a new bond linking the government and the public, has gradually become the focus of innovation in government services. The paper focuses on the e-Government service quality issues from the perspective of users. Design/methodology/approach: From the aspects of online service quality perception and offline service quality perception, based on IS Success model and SERQUAL model, e-Government Services Quality model has been set up with information quality, system quality and service quality as key factors. Then, the survey method was applied to collect data and then to test the model. Findings: It was found that users’ perception of offline service quality has a significant effect on improving their perception of online service quality, and online service quality perception has a significant effect on public satisfaction of e-Government services; information clarity, system security and stability, interactive services and “one-stop” services all have a significant effect on public satisfaction of e-Government services. However, offline service quality perception has certain positive effect on public satisfaction of e-Government services but not dramatically. Research limitations/implications: Mobile e-Government as an important direction of the development of e-Government, in the future, we will study more about mobile e-Government services channels. Originality/value: This study further develops the theory of information system service quality, and also provides a theoretical reference for government departments. On the one hand, based on the characteristics of e-government system, information quality, system quality and service quality in the previous system service model are further discussed; on the other hand, both online and offline services are taken into consideration in the information system service model, thus establishing the e-government services quality model and making an indepth study of the integration effect of online and offline services. Its conclusions can be references for the application of traditional information system service model in the field of e-government.Peer Reviewe