12,316 research outputs found
A concept–relationship acquisition and inference approach for hierarchical taxonomy construction from tags
Author name used in this publication: W. M. WangAuthor name used in this publication: C. F. CheungAuthor name used in this publication: Adela S. M. Lau2009-2010 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe
Molecular characterization of HbEREBP2, a jasmonateresponsive transcription factor from Hevea brasiliensis Muell. Arg.
Transcription factors of AP2/ERF superfamily are generally involved in defense responses of plants to biotic and abiotic stresses. Although, defense proteins are present in abundance in laticifers of rubber tree, little is known about their transcriptional regulation. In this study, a full length cDNA, referred to as HbEREBP2 was characterized by means of bioinformatic analysis and quantitative real-time RT-PCR. The HbEREBP2 was 786-bp in length and contained a 480-bp open reading frame (ORF) encoding a protein of 159 amino acid residues. Bioinformatic analysis showed that the deduced amino acid sequence of HbEREBP2 had a specific domain of AP2 superfamily and shared relative high identity with members of CBF/DREB subfamily from different plant species. Quantitative real-time RT-PCR revealed that methyl jasmonate was more effective than ethylene and rapidly than mechanical wounding on upregulating HbEREBP2 expression. The results suggest that HbEREBP2 may be involved in the regulation of jasmonate-mediated defense responses in laticifers of rubber tree.Key words: Hevea brasiliensis, Laticifer, defense proteins, AP2/ERF transcription factor, Methyl jasmonates, Ethephon, mechanical wounding
Performance modelling and analysis of software defined networking
Software Defined Networking (SDN) is an emerging architecture for the next-generation Internet, providing unprecedented network programmability to handle the explosive growth of Big Data driven by the popularisation of smart mobile devices and the pervasiveness of content-rich multimedia applications. In order to quantitatively investigate the performance characteristics of SDN networks, several research efforts from both simulation experiments and analytical modelling have been reported in the current literature. Among those studies, analytical modelling has demonstrated its superiority in terms of cost-effectiveness in the evaluation of large-scale networks. However, for analytical tractability and simplification, existing analytical models are derived based on the unrealistic assumptions that the network traffic follows the Poisson process which is suitable to model non-bursty text data and the data plane of SDN is modelled by one simplified Single Server Single Queue (SSSQ) system. Recent measurement studies have shown that, due to the features of heavy volume and high velocity, the multimedia big data generated by real-world multimedia applications reveals the bursty and correlated nature in the network transmission. With the aim of the capturing such features of realistic traffic patterns and obtaining a comprehensive and deeper understanding of the performance behaviour of SDN networks, this paper presents a new analytical model to investigate the performance of SDN in the presence of the bursty and correlated arrivals modelled by Markov Modulated Poisson Process (MMPP). The Quality-of-Service performance metrics in terms of the average latency and average network throughput of the SDN networks are derived based on the developed analytical model. To consider realistic multi-queue system of forwarding elements, a Priority-Queue (PQ) system is adopted to model SDN data plane. To address the challenging problem of obtaining the key performance metrics, e.g., queue length distribution of PQ system with a given service capacity, a versatile methodology extending the Empty Buffer Approximation (EBA) method is proposed to facilitate the decomposition of such a PQ system to two SSSQ systems. The validity of the proposed model is demonstrated through extensive simulation experiments. To illustrate its application, the developed model is then utilised to study the strategy of the network configuration and resource allocation in SDN networksThis work is supported by the EU FP7 “QUICK” Project (Grant NO. PIRSES-GA-2013-612652) and the
National Natural Science Foundation of China (Grant NO. 61303241)
MiR-637 maintains the balance between adipocytes and osteoblasts by directly targeting Osterix
Bone development is dynamically regulated by homeostasis, in which a balance between adipocytes and osteoblasts is maintained. Disruption of this differentiation balance leads to various bone-related metabolic diseases, including osteoporosis. In the present study, a primate-specific microRNA (miR-637) was found to be involved in the differentiation of human mesenchymal stem cells (hMSCs). Our preliminary data indicated that miR-637 suppressed the growth of hMSCs and induced S-phase arrest. Expression of miR-637 was increased during adipocyte differentiation (AD), whereas it was decreased during osteoblast differentiation (OS), which suggests miR-637 could act as a mediator of adipoosteogenic differentiation. Osterix (Osx), a significant transcription factor of osteoblasts, was shown to be a direct target of miR-637, which significantly enhanced AD and suppressed OS in hMSCs through direct suppression of Osx expression. Furthermore, miR-637 also significantly enhanced de novo adipogenesis in nude mice. In conclusion, our data indicated that the expression of miR-637 was indispensable for maintaining the balance of adipocytes and osteoblasts. Disruption of miR-637 expression patterns leads to irreversible damage to the balance of differentiation in bone marrow. © 2011 Zhang et al.published_or_final_versio
Parental pro-smoking practices and smoking susceptibility among children in Hong Kong
Conference Theme: Tobacco and Non-Communicable DiseasesPoster Discussion 61. Assessing the Factors that Influence Tobacco Use: no. PD-1313-21BACKGROUND: Parental influence on children smoking is well known, but most studies focused on general parenting and less on smoking-specific parental practices. We investigated the association between some parental pro-smoking practices (PPP) and children smoking susceptibility. DESIGN/METHODS: Among 100 primary schools with students viewing an anti-smoking drama performance commissioned by the Hong Kong Council on Smoking and Health in 2012/13, 7 were randomly selected and 1255 primary 2-4 students (mean age 8.5±0.02, 42.8% boys) completed an anonymous self-administered questionnaire. Fifteen specific items of PPP in the past 30 days were …published_or_final_versio
Family smoking, exposure to secondhand smoke at home and family unhappiness in children
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Excitation Spectra And Hard-core Thermodynamics Of Bosonic Atoms In Optical Superlattices
A generalized double-well-basis coupled representation is proposed to investigate excitation spectra and thermodynamics of bosonic atoms in double-well optical superlattices. In the hard-core limit and with a filling factor of one, excitations describing the creation of pairs of a doubly occupied state and a simultaneous empty state, and those from a symmetric singly occupied state to an antisymmetric state are carefully analyzed and their excitation spectra are calculated within mean-field theory. Based on the hard-core statistics, the equilibrium properties such as heat capacity and particle populations are studied in detail. The cases with other filling factors are also briefly discussed.published_or_final_versio
A laboratory competency examination in microbiology
© FEMS 2018. All rights reserved. The American Society for Microbiology's curricular guidelines for Introductory Microbiology highlighted key laboratory skills in the isolation, visualization and identification of microorganisms as core learning objectives in the discipline. Since the publication of these guidelines in 2012, there has been a paucity of diagnostic assessment tools in the literature that can be used to assess competencies in the microbiology laboratory. This project aimed to establish a laboratory competency examination for introductory microbiology, with tasks specifically aligned to laboratory skills and learning outcomes outlined in curricular guidelines for microbiology. A Laboratory Competency Examination assessing student skills in light microscopy, Gram-staining, pure culture, aseptic technique, serial dilution, dilution calculations and pipetting was developed at The University of Queensland, Australia. The Laboratory Competency Examination was field-tested in a large introductory microbiology subject (~400 students), and student performance and learning gains data were collected from 2016 to 2017 to evaluate the validity of the assessment. The resulting laboratory assessment is presented as an endpoint diagnostic tool for assessing laboratory competency that can be readily adapted towards different educational contexts
High prevalence of mixed infections by Helicobacter pylori in Hong Kong: Metronidazole sensitivity and overall genotype
Background: Diversity in metronidazole susceptibility and genotypes of Helicobacter pylori have been reported with varying results in different areas. Aims: To investigate the prevalence of multiple strain infection in a symptomatic Chinese population and to determine the metronidazole susceptibility pattern and genotypic characteristics of these infecting strains. Methods: Gastric biopsies from antrum, body and cardia were taken during upper endoscopy in symptomatic patients referred to our department. Pooled cultures and single colony isolates were obtained and tested for metronidazole susceptibility and random amplified polymorphic DNA (RAPD) fingerprint patterns. Results: A total of 461 isolates were successfully cultured from 46 patients. Fifty-seven per cent of subjects had metronidazole-resistant strains. Among them, 77% carried a mixture of sensitive and resistant strains, non-uniformly distributed in the gastric mucosa. Mixed genotypes were found by RAPD typing in 24% of subjects. These did not correlate with the metronidazole susceptibility/resistance pattern. Conclusion: H. pylori infections with mixed metronidazole sensitive/resistant strains and mixed genotypes are common in Hong Kong. This makes it prudent to use bacterial strains from several biopsy sites when testing for traits such as drug resistance or virulence in relation to disease.postprin
Plasma-nitrided Ga2O3(Gd2O3) as interfacial passivation layer for InGaAs metal-oxide-semiconductor capacitor with HfTiON gate dielectric
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