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1.
Review helpfulness is attracting increasing attention of practitioners and academics. It helps in reducing risks and uncertainty faced by users in online shopping. This study examines uninvestigated variables by looking at not only the review characteristics but also important indicators of reviewers. Several significant review content and two reviewer variables are proposed and an effective review helpfulness prediction model is built using stochastic gradient boosting learning method. This study derived a mechanism to extract novel review content variables from review text. Six popular machine learning models and three real-life Amazon review data sets are used for analysis. Our results are robust to several product categories and along three Amazon review data sets. The results show that review content variables deliver the best performance as compared to the reviewer and state-of-the-art baseline as a standalone model. This study finds that reviewer helpfulness per day and syllables in review text strongly relates to review helpfulness. Moreover, the number of space, aux verb, drives words in review text and productivity score of a reviewer are also effective predictors of review helpfulness. The findings will help customers to write better reviews, help retailers to manage their websites intelligently and aid customers in their product purchasing decisions. 相似文献
2.
D P Sen Gupta 《Resonance》2007,12(3):54-69
Alternating Current (AC) is used all over the world today. In India we use AC at 50 Hz (cycles per second) and in USA and
Canada at 60 Hz. During the latter part of the 19th century, even during the early part of the 20th century, Direct Current
or DC was widely used. Had we continued with DC, electricity would not have been as widely available as it is today and its
use would have been cumbersome, costly and severely restricted. We owe it mainly to the Serbian genius Nikola Tesla that electricity
has reached almost every nook and corner of most continents. 相似文献
3.
Yashika Gupta V. Mallika D. K. Srivastava 《Indian journal of clinical biochemistry : IJCB》2005,20(1):87-94
Platelets play a vital role in the progression of atherosclerosis and thrombosis, a major cause of death worldwide. Platelets
are activated by many triggers like elevated LDL in blood resulting in aggregation and formation of plaque. The purpose of
this study was to investigate the effect of LDL and signal transduction inhibitor on the activation of platelets in Ischaemic
risk subjects. Platelets from IHD and hyperlipidemic subjects were hypersensitive to ADP, as higher levels of platelet aggregation
were observed in these groups. LDL from IHD hyperlipidemic subjects was more effective in activating platelets from any other
group. Ox-LDL was more effective in activating platelets than native-LDL as monitored by level of platelet aggregation induced
by PAF and thrombin. Calcium channel blocker, nifedipine and verapamil inhibited platelet aggregation at micromolar level.
Protein kinase inhibitor, staurosporine was effective in inhibiting ADP induced aggregation at nanomolar level. 相似文献
4.
Pushpendra KG Harindra SB Pawan LK Neeraj K Ajay K Reyazul RM Amita M Jitendra K 《Journal of Zhejiang University. Science. B》2007,8(11):807-814
Quantitative trait loci (QTL) analysis was conducted in bread wheat for 14 important traits utilizing data from four different mapping populations involving different approaches of QTL analysis. Analysis for grain protein content (GPC) sug- gested that the major part of genetic variation for this trait is due to environmental interactions. In contrast, pre-harvest sprouting tolerance (PHST) was controlled mainly by main effect QTL (M-QTL) with very little genetic variation due to environmental interactions; a major QTL for PHST was detected on chromosome arm 3AL. For grain weight, one QTL each was detected on chromosome arms 1AS, 2BS and 7AS. QTL for 4 growth related traits taken together detected by different methods ranged from 37 to 40; nine QTL that were detected by single-locus as well as two-locus analyses were all M-QTL. Similarly, single-locus and two-locus QTL analyses for seven yield and yield contributing traits in two populations respectively allowed detection of 25 and 50 QTL by composite interval mapping (CIM), 16 and 25 QTL by multiple-trait composite interval mapping (MCIM) and 38 and 37 QTL by two-locus analyses. These studies should prove useful in QTL cloning and wheat improvement through marker aided selection. 相似文献
5.
6.
Ranbir Singh Malik 《Asia Pacific Journal of Education》2015,35(1):27-39
Evidence from Australia lends support to the “Asian high achieving syndrome” in Chinese-Australian students and “self-deprivation syndrome” in Anglo-Australian students. Applying ethnographic case studies approach for doctoral thesis the author collected data on a longitudinal basis from homes and school of these students. All of these students attended the same school located in a predominantly middle class suburb of Perth Metropolitan area in Western Australia. Chinese-Australian families had settled in Perth from Malaysia, Singapore and Hong Kong, whereas Anglo-Australian families had been residing in Perth for three generations. Impetus to revisit these students (now young adults with their own families) 10 years later came from an urge to test the validity of the prediction the author had made in the concluding chapter of his doctoral thesis. The author had claimed that “if Anglo-Australian parents keep on dwelling in the era of 1950s and 1960s and do not change their laid-back attitude about education, their children could eventually be under-privileged in their own country”. Ten years later, the author undertook a follow-up study on these young adults from six of the eight original families in order to find out their occupational destinations and future aspirations. Data for the follow-up study were collected from these young adults and their parents. These research cases were interviewed twice, each time approximately for two hours and their parents were interviewed once for two to three hours. The purpose of this paper is to report the findings of the follow-up study which reveals a remarkable relationship between the attitude towards schooling and academic performance with their subsequent occupational destination. 相似文献
7.
Srivastava Himanshu Gupta Ankush Raveendran Aswathy 《Cultural Studies of Science Education》2022,17(2):301-330
Cultural Studies of Science Education - The M(East) ward of Mumbai is home to one of Asia’s largest open landfill sites. Waste, therefore, is a source of livelihood for millions of people... 相似文献
8.
University Technical Colleges (UTCs) are newly established (since 2010–11) technical and vocational secondary schools in England, catering for young people aged 14–19. The schools focus strongly on delivering vocational, alongside Science, Technology, Engineering and Mathematics (STEM)-focused academic, qualifications. The colleges have been introduced as a new means of improving technical and vocational education and training—a sector which in England has faced problems of low quality and low esteem—and in a wider international context of STEM-trained worker shortages. University Technical Colleges have been advertised as offering state-of-the-art vocational learning, involving access for students to the latest equipment and technologies in key industrial sectors, alongside extensive project-based learning in partnership with employers. However, how have UTC students fared in these respects since the beginning of the coronavirus pandemic and associated lockdowns in 2020? In this paper we report on results from a survey of 252 students across two UTCs in England, exploring the technical and vocational learning experiences of these students during the exceptional 2019–20 academic year. Findings from the survey reveal lost learning and training opportunities during the pandemic, particularly where courses with practical elements relied on specific equipment and facilities that became inaccessible during lockdown. The survey also highlights disruptions to apprenticeship arrangements, work experience plans and other engagement with employers. Students in some instances have been effectively forced to stay on in education owing to reduced apprenticeship and employment opportunities for school-leavers. We find evidence of students adapting their aspirations and career goals to the new economic circumstances. 相似文献
9.
Gururao Hariprasad Divya Kota Sundararajan Baskar Singh Alagiri Srinivasan Souparno Adhikary 《Indian journal of clinical biochemistry : IJCB》2014,29(4):430-441
Clonorchis sinensis or the Chinese liver fluke is one of the most prevalent parasites affecting a major population in the oriental countries. The parasite lacks lipid generating mechanisms but is exposed to fatty acid rich bile in the liver. A secretory phospholipase A2, an enzyme that breaks down complex lipids, is important for the growth of the parasite. The enzyme is also implicated in the pathogenesis leading up to the hepatic fibrosis and its complications including cancer. The five isoforms of this particular enzyme from the parasite therefore qualify as potential drug targets. In this study, a detailed structural and ligand binding analysis of the isoforms has been done by modeling. The overall three dimensional structures of the isoforms are well conserved with three helices and a β-wing stabilized by four disulfide bonds. There are characteristic differences at the calcium binding loop, hydrophobic channel and the C-terminal domain that can potentially be exploited for drug binding. But the most significant feature pertains to the catalytic site where the isoforms exhibit three variations of either a histidine-aspartate-tyrosine or histidine-glutamate-tyrosine or histidine-aspartate-phenylalanine. Molecular docking studies show that isoform specific residues and their conformations in the substrate binding hydrophobic channel make unique interactions with certain inhibitor molecules resulting in a perfect tight fit. The proposed ligand molecules have a predicted affinity in micro-molar to nano-molar range. Interestingly, few of the ligand binding interaction patterns is in accordance to the phylogenetic studies to thereby establish the usefulness of evolutionary mechanisms in aiding ligand design. The molecular diversity of the parasitic PLA2 described in this study provides a platform for personalized medicine in the therapeutics of clonorchiasis.
Electronic supplementary material
The online version of this article (doi:10.1007/s12291-013-0377-1) contains supplementary material, which is available to authorized users. 相似文献10.
Amna Khan Farzana Hayat Ahmad Muhammad Muddassir Malik 《Education and Information Technologies》2017,22(6):2767-2804
This study aimed to identify the impact of a game based learning (GBL) application using computer technologies on student engagement in secondary school science classrooms. The literature reveals that conventional Science teaching techniques (teacher-centered lecture and teaching), which foster rote learning among students, are one of the major concerns in Pakistan Education system. This leads to student disengagement in science lessons eventually resulting in student absenteeism and dropouts from the schools. This study consisted of five stages: (1) examining the impact of Digital Game-Based Learning (DGBL) and gamification on engagement, learning and gender difference, and literature related to using DGBL models for instructional design; (2) planning learning activities and developing a GBL application based on a specific content in Science; (3) conducting an intervention with a sample of 72 participants of 8th grade (aged 12–15) in a low cost private school of Pakistan following quasi-experimental research framework; (4) observing behaviour and emotions of the participants during science lessons; (5) conducting pre and post tests to assess the learning outcomes of participants followed by focus groups discussion. Analysis from Friedman test, Mann-Whitney U test, and Wilcoxon Signed Rank test show that the GBL application has a positive influence on student engagement. However, GBL application was not equally effective for all students since girls outperformed boys in terms of engagement and learning outcomes. This study gives insights into the development of better educational games to promote student learning. 相似文献