80 research outputs found

    Always Strengthen Your Strengths: A Drift-Aware Incremental Learning Framework for CTR Prediction

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    Click-through rate (CTR) prediction is of great importance in recommendation systems and online advertising platforms. When served in industrial scenarios, the user-generated data observed by the CTR model typically arrives as a stream. Streaming data has the characteristic that the underlying distribution drifts over time and may recur. This can lead to catastrophic forgetting if the model simply adapts to new data distribution all the time. Also, it's inefficient to relearn distribution that has been occurred. Due to memory constraints and diversity of data distributions in large-scale industrial applications, conventional strategies for catastrophic forgetting such as replay, parameter isolation, and knowledge distillation are difficult to be deployed. In this work, we design a novel drift-aware incremental learning framework based on ensemble learning to address catastrophic forgetting in CTR prediction. With explicit error-based drift detection on streaming data, the framework further strengthens well-adapted ensembles and freezes ensembles that do not match the input distribution avoiding catastrophic interference. Both evaluations on offline experiments and A/B test shows that our method outperforms all baselines considered.Comment: This work has been accepted by SIGIR2

    Chinese language teachers’ dichotomous identities when teaching ingroup and outgroup students

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    Research into second language teacher identity has experienced a shift in recent years from a cognitive perspective to social constructionist orientation. The existing research in Chinese language literature in relation to Foreign Language (CFL) teachers’ identity shift is principally in relation to the change of social, cultural, and institutional contexts. Built on the current literature, this research asks: “How might teachers’ self-images or self-conceptualizations be renegotiated when they are located within their own mainstream cultural and educational system, yet comprised of students from various cultural backgrounds?” The data were collected from a group of CFL teachers in a South China university. The research found that students’ backgrounds largely impacted on, and led to, the teachers’ dichotomous relational identities, but did not dramatically change the teachers’ perception on what or how much subject knowledge to be possessed to make an ideal CFL teacher. This attribute of their identity was sustained even though the teaching content was modified at a practical level in response to groups’ differences. Further, the CFL teachers’ pedagogical identity remained stable with only minor modifications when teaching “ingroups” and “outgroups” of students

    In vitro and in vivo germ line potential of stem cells derived from newborn mouse skin

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    We previously reported that fetal porcine skin-derived stem cells were capable of differentiation into oocyte-like cells (OLCs). Here we report that newborn mice skin-derived stem cells are also capable of differentiating into early OLCs. Using stem cells from mice that are transgenic for Oct4 germline distal enhancer-GFP, germ cells resulting from their differentiation are expected to be GFP+. After differentiation, some GFP+ OLCs reached 40-45 μM and expressed oocyte markers. Flow cytometric analysis revealed that ∼0.3% of the freshly isolated skin cells were GFP+. The GFP-positive cells increased to ∼7% after differentiation, suggesting that the GFP+ cells could be of in vivo origin, but are more likely induced upon being cultured in vitro. To study the in vivo germ cell potential of skin-derived cells, they were aggregated with newborn ovarian cells, and transplanted under the kidney capsule of ovariectomized mice. GFP+ oocytes were identified within a subpopulation of follicles in the resulting growth. Our finding that early oocytes can be differentiated from mice skin-derived cells in defined medium may offer a new in vitro model to study germ cell formation and oogenesis. © 2011 Dyce et al

    High-throughput next-generation sequencing technologies foster new cutting-edge computing techniques in bioinformatics

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    The advent of high-throughput next generation sequencing technologies have fostered enormous potential applications of supercomputing techniques in genome sequencing, epi-genetics, metagenomics, personalized medicine, discovery of non-coding RNAs and protein-binding sites. To this end, the 2008 International Conference on Bioinformatics and Computational Biology (Biocomp) – 2008 World Congress on Computer Science, Computer Engineering and Applied Computing (Worldcomp) was designed to promote synergistic inter/multidisciplinary research and education in response to the current research trends and advances. The conference attracted more than two thousand scientists, medical doctors, engineers, professors and students gathered at Las Vegas, Nevada, USA during July 14–17 and received great success. Supported by International Society of Intelligent Biological Medicine (ISIBM), International Journal of Computational Biology and Drug Design (IJCBDD), International Journal of Functional Informatics and Personalized Medicine (IJFIPM) and the leading research laboratories from Harvard, M.I.T., Purdue, UIUC, UCLA, Georgia Tech, UT Austin, U. of Minnesota, U. of Iowa etc, the conference received thousands of research papers. Each submitted paper was reviewed by at least three reviewers and accepted papers were required to satisfy reviewers' comments. Finally, the review board and the committee decided to select only 19 high-quality research papers for inclusion in this supplement to BMC Genomics based on the peer reviews only. The conference committee was very grateful for the Plenary Keynote Lectures given by: Dr. Brian D. Athey (University of Michigan Medical School), Dr. Vladimir N. Uversky (Indiana University School of Medicine), Dr. David A. Patterson (Member of United States National Academy of Sciences and National Academy of Engineering, University of California at Berkeley) and Anousheh Ansari (Prodea Systems, Space Ambassador). The theme of the conference to promote synergistic research and education has been achieved successfully

    Vascular endothelial growth factor C promotes cervical cancer metastasis via up-regulation and activation of RhoA/ROCK-2/moesin cascade

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    <p>Abstract</p> <p>Background</p> <p>The elevated expression of vascular endothelial growth factor C (VEGF-C) is correlated with clinical cervical cancer metastasis and patient survival, which is interpreted by VEGF-C functions to stimulate angiogenesis and lymphatic genesis. However, the direct impact of VEGF-C on cervical cancer cell motility remains largely unknown.</p> <p>Methods</p> <p>In this study, we investigated the effects of VEGF-C on actin cytoskeleton remodeling and on cervical cancer cell migration and invasion and how the actin-regulatory protein, moesin regulated these effects through RhoA/ROCK-2 signaling pathway.</p> <p>Results</p> <p>On cervical carcinoma cell line SiHa cells, exposure of VEGF-C triggered remodeling of the actin cytoskeleton and the formation of membrane ruffles, which was required for cell movement. VEGF-C significantly enhanced SiHa cells horizontal migration and three-dimensional invasion into matrices. These actions were dependent on increased expression and phosphorylation of the actin-regulatory protein moesin and specific moesin siRNA severely impaired VEGF-C stimulated-cell migration. The extracellular small GTPase RhoA/ROCK-2 cascade mediated the increased moesin expression and phosphorylation, which was discovered by the use of Y-27632, a specific inhibitor of Rho kinase and by transfected constitutively active, dominant-negative RhoA as well as ROCK-2 SiRNA. Furthermore, in the surgical cervical specimen from the patients with FIGO stage at cervical intra-epithelial neoplasia and I-II cervical squamous cell carcinoma, the expression levels of moesin were found to be significantly correlated with tumor malignancy and metastasis.</p> <p>Conclusions</p> <p>These results implied that VEGF-C promoted cervical cancer metastasis by upregulation and activation of moesin protein through RhoA/ROCK-2 pathway. Our findings offer new insight into the role of VEGF-C on cervical cancer progression and may provide potential targets for cervical cancer therapy.</p

    In Vitro and In Vivo Germ Line Potential of Stem Cells Derived from Newborn Mouse Skin

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    We previously reported that fetal porcine skin-derived stem cells were capable of differentiation into oocyte-like cells (OLCs). Here we report that newborn mice skin-derived stem cells are also capable of differentiating into early OLCs. Using stem cells from mice that are transgenic for Oct4 germline distal enhancer-GFP, germ cells resulting from their differentiation are expected to be GFP+. After differentiation, some GFP+ OLCs reached 40–45 µM and expressed oocyte markers. Flow cytometric analysis revealed that ∼0.3% of the freshly isolated skin cells were GFP+. The GFP-positive cells increased to ∼7% after differentiation, suggesting that the GFP+ cells could be of in vivo origin, but are more likely induced upon being cultured in vitro. To study the in vivo germ cell potential of skin-derived cells, they were aggregated with newborn ovarian cells, and transplanted under the kidney capsule of ovariectomized mice. GFP+ oocytes were identified within a subpopulation of follicles in the resulting growth. Our finding that early oocytes can be differentiated from mice skin-derived cells in defined medium may offer a new in vitro model to study germ cell formation and oogenesis

    (Work integrated learning for higher degree research : a pilot study of bilingual teacher-researcher education program)

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    Different from traditional postgraduate training which produces researchers who pursue research and work at universities, Work Integrated Learning HDR programs are for a new generation of multiskilled teacher-researchers. This paper reports a ten year of ‘work integrated leaning, higher degree research’ (WIL HDR) program at an Australian university – which is a ‘research oriented, school engaged teacher-researcher education’ (ROSETE). The enrolled candidates in this program are a group of Chinese-English bilingual teacher-researchers. They substantially engage in teacher-research in schools of Sydney region (2 days/week) throughout their candidature, teaching Chinese to school students. The focus of the study explores how working-integrated learning may enable the bilingual candidates to construct theoretic-pedagogical contributions to making Chinese learnable for monolingual English speaking students. This research found that work integrated leaning provided HDR candidates with sufficient opportunity to negotiate the knowledge production through workplaces and enabled them to have direct positive impact on end-users – school learners

    Simple and sensitive determination of nucleic acid by Rayleigh light scattering technique with methyl green-CTMAB

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    1121-1123A method is presented for the determination of nucleic acid, based on the enhancement of Rayleigh light scattering (RLS) of methyl green (MG)-CTMAB in the pH range 6.9-7.2 at 414.0 nm. The enhanced intensity of RLS is proportional to the concentration of nucleic acid in the range 2.5×10-8-2.0×10-6g/ml for calf thymus (ct)DNA, 2.5×10-8-2.0×10-6g/ml  for fish sperm (fs)DNA, 7.5×10-8-2.0×10-6g/ml for yeast (y)RNA. The detection limits (3σ) are 7.8, 2.6, 9.9 ng/ml for ctDNA, fsDNA and yRNA respectively. Besides its high sensitivity, it has some other advantages: simplicity of operation, commonality of spectrometer and reagents, good stability of chemical system and reproducibility. The procedure has been successfully applied to the determination of nucleic acid in synthetic samples
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