The Pursuit of Conversion: Effects of Mediating Channels on Product Choices and Purchase Propensities in Social Commerce Platforms

This study elucidates the effectiveness of intermediary channels in driving sales at social commerce sites (SCSs). Using a panel data, we investigate how the external intermediary channels through which consumers arrive at SCSs influence product choice and purchase likelihood. In addition, we scrutinize the extent to which product categories with varying quality moderate the relationship between consumers’ channel-related behaviors and purchase propensities. Furthermore, we examine how external channels “collaborate” with internal channels to increase purchase likelihood. The findings suggest that consumers who enter the SCS through direct apps and portals engage in more proactive purchasing than do consumers landing at the SCS via metasites or e-mail promotions. Consumers who are directed to the SCS through metasites or e-mail promotions are more likely to purchase experience goods than search goods. Contrary to previous findings, consumers’ purchasing propensities decline, rather than increase, across all channels after the implementation of a recommendation system

Lightweight and Robust Representation of Economic Scales from Satellite Imagery

Satellite imagery has long been an attractive data source that provides a wealth of information on human-inhabited areas. While super resolution satellite images are rapidly becoming available, little study has focused on how to extract meaningful information about human habitation patterns and economic scales from such data. We present READ, a new approach for obtaining essential spatial representation for any given district from high-resolution satellite imagery based on deep neural networks. Our method combines transfer learning and embedded statistics to efficiently learn critical spatial characteristics of arbitrary size areas and represent them into a fixed-length vector with minimal information loss. Even with a small set of labels, READ can distinguish subtle differences between rural and urban areas and infer the degree of urbanization. An extensive evaluation demonstrates the model outperforms the state-of-the-art in predicting economic scales, such as population density for South Korea (R^2=0.9617), and shows a high potential use for developing countries where district-level economic scales are not known.Comment: Accepted for oral presentation at AAAI 202

Different Impacts of Boot Height and Air Bottles on the Mobility of Tall and Short Firefighters

This study conducted biomechanical tests with 21 firefighters and found that there is a significant correlation between boot height and lower body mobility, and that using a fixed boot height mandated by NFPA 1971 standard decreased lower body ranges of motion during various firefighters\u27 job-related tasks. Statistical analysis of large anthropometric data also shows a fixed boot height cannot accommodate a wide range of firefighters\u27 leg length. These findings indicate that shorter firefighters are likely to have limited lower body mobility due to reduced clearance between the knee and top of the boot, and thus decreased space causing greater mechanical binding between multiple layers of turnout pants. This study also shows a greater negative impact of fixed length of SCBA cylinder on short firefighters on their upper body mobility, evidenced by limited range of motion in neck extension and lumbopelvic flexion while carrying firegear compared to without any firegear

Perturbation theory for non-spherical fluids based on discretization of the interactions

7 páginas, 5 figuras; PACS: 65.20.De, 61.20.JaAn extension of the discrete perturbation theory [A. L. Benavides and A. Gil-Villegas, Mol. Phys. 97(12), 1225 (1999)10.1080/00268979909482924] accounting for non-spherical interactions is presented. An analytical expression for the Helmholtz free energy for an equivalent discrete potential is given as a function of density, temperature, and intermolecular parameters with implicit shape dependence. The presented procedure is suitable for the description of the thermodynamics of general intermolecular potential models of arbitrary shape. The overlap and dispersion forces are represented by a discrete potential formed by a sequence of square-well and square-shoulders potentials of shape-dependent widths. By varying the intermolecular parameters through their geometrical dependence, some illustrative cases of square-well spherocylinders and Kihara fluids are considered, and their vapor-liquid phase diagrams are tested against available simulation data. It is found that this theoretical approach is able to reproduce qualitatively and quantitatively well the Monte Carlo data for the selected potentials, except near the critical region.A.L.B. acknowledges funding received by Grant No. 152684 CONACYT (México). F.G. acknowledges funding through Project No. P07-FQM-02600 (Junta de Andalucía-FEDER) for his postdoctoral fellowship.Peer reviewe

Recognition of Transmembrane Protein 39A as a Tumor-Specific Marker in Brain Tumor

Transmembrane protein 39A (TMEM39A) belongs to the TMEM39 family. TMEM39A gene is a susceptibility locus for multiple sclerosis. In addition, TMEM39A seems to be implicated in systemic lupus erythematosus. However, any possible involvement of TMEM39A in cancer remains largely unknown. In the present report, we provide evidence that TMEM39A may play a role in brain tumors. Western blotting using an anti-TMEM39A antibody indicated that TMEM39A was overexpressed in glioblastoma cell lines, including U87-MG and U251-MG. Deep-sequencing transcriptomic profiling of U87-MG and U251-MG cells revealed that TMEM39A transcripts were upregulated in such cells compared with those of the cerebral cortex. Confocal microscopic analysis of U251-MG cells stained with anti-TMEM39A antibody showed that TMEM39A was located in dot-like structures lying close to the nucleus. TMEM39A probably located to mitochondria or to endosomes. Immunohistochemical analysis of glioma tissue specimens indicated that TMEM39A was markedly upregulated in such samples. Bioinformatic analysis of the Rembrandt knowledge base also supported upregulation of TMEM39A mRNA levels in glioma patients. Together, the results afford strong evidence that TMEM39A is upregulated in glioma cell lines and glioma tissue specimens. Therefore, TMEM39A may serve as a novel diagnostic marker of, and a therapeutic target for, gliomas and other cancers

Expansion and long-range differentiation of the NKT cell lineage in mice expressing CD1d exclusively on cortical thymocytes

Unlike conventional major histocompatibility complex–restricted T cells, Vα14-Jα18 NKT cell lineage precursors engage in cognate interactions with CD1d-expressing bone marrow–derived cells that are both necessary and sufficient for their thymic selection and differentiation, but the nature and sequence of these interactions remain partially understood. After positive selection mediated by CD1d-expressing cortical thymocytes, the mature NKT cell lineage undergoes a series of changes suggesting antigen priming by a professional antigen-presenting cell, including extensive cell division, acquisition of a memory phenotype, the ability to produce interleukin-4 and interferon-γ, and the expression of a panoply of NK receptors. By using a combined transgenic and chimeric approach to restrict CD1d expression to cortical thymocytes and to prevent expression on other hematopoietic cell types such as dendritic cells, macrophages, or B cells, we found that, to a large extent, expansion and differentiation events could be imparted by a single-cognate interaction with CD1d-expressing cortical thymocytes. These surprising findings suggest that, unlike thymic epithelial cells, cortical thymocytes can provide unexpected, cell type–specific signals leading to lineage expansion and NKT cell differentiation