120 research outputs found
Sparse Matrix-based Random Projection for Classification
As a typical dimensionality reduction technique, random projection can be
simply implemented with linear projection, while maintaining the pairwise
distances of high-dimensional data with high probability. Considering this
technique is mainly exploited for the task of classification, this paper is
developed to study the construction of random matrix from the viewpoint of
feature selection, rather than of traditional distance preservation. This
yields a somewhat surprising theoretical result, that is, the sparse random
matrix with exactly one nonzero element per column, can present better feature
selection performance than other more dense matrices, if the projection
dimension is sufficiently large (namely, not much smaller than the number of
feature elements); otherwise, it will perform comparably to others. For random
projection, this theoretical result implies considerable improvement on both
complexity and performance, which is widely confirmed with the classification
experiments on both synthetic data and real data
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Conspecific and allospecific larval extracts entice mosquitoes to lay eggs and may be used in attract-and-kill control strategy.
One of the strategies of integrated vector management is to lure gravid mosquitoes for surveillance purposes or to entice them to lay eggs in water containing toxins that kill the offspring (attract-and-kill or trap-and-kill). Typically, the major challenge of this approach is the development of a lure that stimulates oviposition plus a toxin with no deterrent effect. Bacillus thuringiensis var. israelensis (Bti) satisfies the latter criterion, but lures for these autocidal gravid traps are sorely needed. We observed that gravid Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus laid significantly more eggs in cups with extracts from 4th-stage larvae (4 L) of the same or different species. No activity was found when 4 L were extracted with hexane, diethyl ether, methanol, or butanol, but activity was observed with dimethyl sulfoxide extracts. Larval extracts contained both oviposition stimulant(s)/attractant(s) and deterrent(s), which partitioned in the water and hexane phases, respectively. Lyophilized larval extracts were active after a month, but activity was reduced by keeping the sample at 4 °C. In the tested range of 0.1 to 1 larvae-equivalent per milliliter, oviposition activity increased in a dose-dependent manner. In field experiments, Ae. aegpti laid significantly more eggs in traps loaded with larval extracts plus Bti than in control traps with water plus Bti
Thermoplastic Elastomers Based on Block, Graft, and Star Copolymers
In this book chapter, we focus on recent advances in thermoplastic elastomers based on synthetic polymers from the aspects of polymer architectures such as linear block, graft, and star copolymers. The first section is an introduction that covers a brief history and classification of thermoplastic elastomers (TPEs). The second section summarizes ABA triblock copolymers synthesized by various methods for TPE applications. The third section reviews TPEs based on graft copolymers, and the fourth section reviews TPEs based on star copolymers. The differences between TPE research in academia and industry are addressed in the last section as a perspective, with a view toward the generation of new, advanced, commercially viable TPEs
Design for Online Deliberative Processes and Technologies: Towards a Multidisciplinary Research Agenda
There has been rapidly growing interest in studying and designing online
deliberative processes and technologies. This SIG aims at providing a venue for
continuous and constructive dialogue between social, political and cognitive
sciences as well as computer science, HCI, and CSCW. Through an online
community and a modified version of world cafe discussions, we contribute to
the definition of the theoretical building blocks, the identification of a
research agenda for the CHI community, and the network of individuals from
academia, industry, and the public sector who share interests in different
aspects of online deliberation.Comment: CHI'15 Extended Abstracts, Apr 18-23, 2015, Seoul, Republic of Korea,
ACM 978-1-4503-3146-3/15/04, 4 page
TSPAN8 promotes cancer cell stemness via activation of sonic Hedgehog signaling
Cancer stem cells (CSCs) represent a major source of treatment resistance and tumor progression. However, regulation of CSCs stemness is not entirely understood. Here, we report that TSPAN8 expression is upregulated in breast CSCs, promotes the expression of the stemness gene NANOG, OCT4, and ALDHA1, and correlates with therapeutic resistance. Mechanistically, TSPAN8 interacts with PTCH1 and inhibits the degradation of the SHH/PTCH1 complex through recruitment of deubiquitinating enzyme ATXN3. This results in the translocation of SMO to cilia, downstream gene expression, resistance of CSCs to chemotherapeutic agents, and enhances tumor formation in mice. Accordingly, expression levels of TSPAN8, PTCH1, SHH, and ATXN3 are positively correlated in human breast cancer specimens, and high TSPAN8 and ATXN3 expression levels correlate with poor prognosis. These findings reveal a molecular basis of TSPAN8-enhanced Sonic Hedgehog signaling and highlight a role for TSPAN8 in promoting cancer stemness
Comprehensive Evaluation of Fruit Quality of Actinidia arguta Based on Principal Component Analysis and Cluster Analysis
In order to scientifically evaluate the fruit quality of different Actinidia arguta varieties and establish the quality evaluation system, 10 Actinidia arguta varieties were used as experimental materials, and the indexes of fruit appearance quality and nutritional quality were measured and compared under edible conditions. The fruit quality of Actinidia arguta was comprehensively evaluated by correlation analysis, principal component analysis and cluster analysis. The results showed that the quality indexes of different varieties of Actinidia arguta were different and correlated. The difference of the content of Vitamin C was largest, and the coefficient of variation was 53.08%. The difference of fruit color brightness (L* value) was the smallest, and the coefficient of variation was 6.04%. By principal component analysis, 18 quality indicators were simplified into 6 principal components, and the cumulative variance contribution rate was 90.571%, which could reflect most of the information of the original quality indexes. The comprehensive scores of quality indexes of 10 Actinidia arguta varieties were ranked as ‘Longcheng No.2’, ‘Kuilü’, ‘Jialü’, ‘Wanlü’, ‘Tianxinbao’, ‘Lübao’, ‘Xinlü’, ‘Cuiyu’, ‘Fenglü’ and ‘Pingllü’. According to cluster analysis, 10 Actinidia arguta varieties were divided into five categories, among which ‘Longcheng No.2’ and ‘Kuilü’ in the first category had better comprehensive quality traits. The study provided a reference for the variety breeding, planting, extension and rational processing and utilization of Actinidia arguta
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