1,142 research outputs found
Online Forum Thread Retrieval using Pseudo Cluster Selection and Voting Techniques
Online forums facilitate knowledge seeking and sharing on the Web. However,
the shared knowledge is not fully utilized due to information overload. Thread
retrieval is one method to overcome information overload. In this paper, we
propose a model that combines two existing approaches: the Pseudo Cluster
Selection and the Voting Techniques. In both, a retrieval system first scores a
list of messages and then ranks threads by aggregating their scored messages.
They differ on what and how to aggregate. The pseudo cluster selection focuses
on input, while voting techniques focus on the aggregation method. Our combined
models focus on the input and the aggregation methods. The result shows that
some combined models are statistically superior to baseline methods.Comment: The original publication is available at
http://www.springerlink.com/. arXiv admin note: substantial text overlap with
arXiv:1212.533
Isotype selection for antibody-based cancer therapy
The clinical application of monoclonal antibodies (mAbs) has revolutionized the field of cancer therapy, as it has enabled the successful treatment of previously untreatable types of cancer. Different mechanisms play a role in the anti‐tumour effect of mAbs. These include blocking of tumour‐specific growth factor receptors or of immune modulatory molecules as well as complement and cell‐mediated tumour cell lysis. Thus, for many mAbs, Fc‐mediated effector functions critically contribute to the efficacy of treatment. As immunoglobulin (Ig) isotypes differ in their ability to bind to Fc receptors on immune cells as well as in their ability to activate complement, they differ in the immune responses they activate. Therefore, the choice of antibody isotype for therapeutic mAbs is dictated by its intended mechanism of action. Considering that clinical efficacy of many mAbs is currently achieved only in subsets of patients, optimal isotype selection and Fc optimization during antibody development may represent an important step towards improved patient outcome. Here, we discuss the current knowledge of the therapeutic effector functions of different isotypes and Fc‐engineering strategies to improve mAbs application
Effect of soil bacteriomes on mycorrhizal colonization by <i>Rhizophagus irregularis</i>:Interactive effects on maize (<i>Zea mays</i> L.) growth under salt stress
In this study, we investigated the interactive effects of the arbuscular mycorrhizal fungus (AMF) Rhizophagus irregularis and soil bacteriomes on maize growth under salt stress (100 mM NaCl) and also the effect of salt and bacteriomes on the mycorrhizal infection levels. We found that soil bacteriomes directly promoted the growth of maize and indirectly enhanced maize biomass by increasing mycorrhizal colonization levels, irrespective of salt stress. Although R. irregularis by itself had no maize growth-promoting effect even at a high mycorrhizal colonization level in roots, its benefits to maize were reflected in other aspects, evidenced by the significantly increased rate of arbuscule formation (a proxy for a functional plant-AMF nutritional exchange) under salinity. A negative correlation between arbuscule colonization and root biomass suggested R. irregularis expands the role of maize roots. Besides, the positive correlation between the overall AMF colonization level and shoot biomass supported the tenet of a positive contribution of R. irregularis to maize growth. Our findings suggest that soil bacteriomes interactively work with R. irregularis, modulating the growth of maize by affecting the colonization of AMF in roots
Default Risk and Equity Returns: A Comparison of the Bank-Based German and the U.S. Financial System
In this paper, we address the question whether the impact of default risk on equity returns depends on the financial system firms operate in. Using an implementation of Merton's option-pricing model for the value of equity to estimate firms' default risk, we construct a factor that measures the excess return of firms with low default risk over firms with high default risk. We then compare results from asset pricing tests for the German and the U.S. stock markets. Since Germany is the prime example of a bank-based financial system, where debt is supposedly a major instrument of corporate governance, we expect that a systematic default risk effect on equity returns should be more pronounced for German rather than U.S. firms. Our evidence suggests that a higher firm default risk systematically leads to lower returns in both capital markets. This contradicts some previous results for the U.S. by Vassalou/Xing (2004), but we show that their default risk factor looses its explanatory power if one includes a default risk factor measured as a factor mimicking portfolio. It further turns out that the composition of corporate debt affects equity returns in Germany. Firms' default risk sensitivities are attenuated the more a firm depends on bank debt financing
Genetic diversity of bacterial wilt caused by <i>Ralstonia solanacearum</i> as assessed by PCR
The current research was conducted to investigate genetic diversity of Ralstonia solanacearum for comparison of different strains that were collected mainly from Netherlands as well as from Bangladesh, Brazil, Kenya, Egypt, Pakistan and Palma. Forty six strains were included in contemporary studies whereas main biovars for these strains included biovar-2 except GMI1000 that belonged to biovar 3. Genetic diversity of bacterial wilt disease caused by R. solancearum was assessed by focusing mainly on three genes i.e. mutL, cbhA and dps. All the genes seem to be conserved but in case of mutL some strains showed divergence. Multi Locus Sequence Typing (MLST) scheme was used in this contemporary research. It was concluded that polymerized chain reaction (PCR) is the most imperative and appropriate modern tool of molecular biology to find genetic diversity in Ralstonia solanacearum causing bacterial wilt
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