EXAMINING THE INFLUENCE OF ONLINE USER GENERATED CONTENT ON CONSUMER CHOICE: VARIETY SEEKING, LEARNING, AND SHARING

Ph.DDOCTOR OF PHILOSOPH

Unraveling the Information Role of Online Reviews: Distinguishing between the Competing Effect, Local and Global Peer Effects on Consumer Choice

This study examines the information role of online reviews on competing products and from local and global peers on consumers’ choice of products. By empirically analyzing a data set from a restaurant review website, we find that a one unit increase in average valence (volume) of spatially adjacent and feature similar alternatives reduces the odds of choosing a focal product by 92.0% (66.6%) and by 72.2% (45.8%) respectively. Competition faced by restaurants, in terms of review valence and volume, is thus stronger along geographical space, rather than characteristics space. The valence, volume and dispersion of valences of reviews posted by local peers are found to have influences on purchase decisions. Importantly, local peer effects exert more significant influences on consumer choices as compared to global peer effects. These new findings on the dimensions of competition, local and global peer effects of online reviews provide implications for academic research and practice

Board gender diversity and carbon proactivity : the influence of cultural factors

Due to inadequate studies, our knowledge of the effect of female directors and national culture on the corporate response to climate change is still limited. To address this gap, the purpose of this paper is to investigate the dynamic relationship between gender diversity on the board of directors and corporate carbon proactivity and how two dimensions of national culture (individualism and indulgence) moderate this relationship. This study focuses on large companies that disclosed carbon-related information via the CDP survey in 2011–2017. Our findings show that gender diversity promotes corporate carbon proactivity. Furthermore, the positive effect of gender diversity on carbon proactivity is weaker when firms are in countries marked by a higher level of individualism and indulgence. As far as we know, this study is the first to explore and document the empirical evidence on the dynamic impact of gender diversity in the corporate governance body and national culture on managers’ climate change behaviors in terms of green proactivity

Tests of relative vertical offsets for several types of GPS receiver antenna phase centers

AbstractThe correction for antenna phase center is considered in processing Global Positioning System (GPS) data collected from a network of GPS ultra-short baselines. Compared with the leveling measurements, the GPS results show that the relative vertical offsets for the pairs of GPS receiver antenna phase centers still exist, although absolute calibration of the antenna phase center variations (PCVs) has been considered. With respect to the TPS CR.G3 antenna, the relative vertical offset for the LEI AT504 antenna is −8.4 mm, the offset for the ASH701945C_M antenna is 5.5 mm, and those for the ASH700936E_C and ASH701945B_M antennas are approximately between −2 mm and −3 mm. The relative offsets for the same type of antennas are approximately 1 mm. By correcting the absolute PCVs, the existing relative offset becomes negligible for horizontal positioning

Experimental Research on Mechanical Properties of Apple Peels

Knowledge of the mechanical properties of apple peel, as the outermost tissue of the fruit, is crucial for the designing of apple harvesting machines. In this study, longitudinal and transverse tensile tests were conducted on peels from the shadow side and sunlit side of two apple cultivars (Starkrimson and Fuji) using an electronic universal testing machine, and tear tests and puncture tests were carried out on peels of both sides as well. The stress-strain curves and tear and puncture force-deformation curves of the peels were acquired and the tensile strength, elastic modulus, failure strain tear strength, puncture strength of the peels were measured. Also, scanning electron microscope images were made. The results showed that the maximum values of tensile strength, elastic modulus, fracture strain, tear strength, and puncture strength were 2.56 MPa, 24.00 MPa, 19.92%, 0.391 kN·m-1, and 0.289 N·mm-2, respectively. The tensile strength, elastic modulus, and puncture strength values for the Starkrimson peels were higher than those for the Fuji peels from the same side. Apple peel is an anisotropic heterogeneous material. The bearing capacity of the peel depends on the number and distribution of microcracks on the surface, and the size and shape of the epidermal cells. The organization and connections between the cells determine the strength of the connections between cells

Identification of regulatory targets of tissue-specific transcription factors: application to retina-specific gene regulation

Identification of tissue-specific gene regulatory networks can yield insights into the molecular basis of a tissue's development, function and pathology. Here, we present a computational approach designed to identify potential regulatory target genes of photoreceptor cell-specific transcription factors (TFs). The approach is based on the hypothesis that genes related to the retina in terms of expression, disease and/or function are more likely to be the targets of retina-specific TFs than other genes. A list of genes that are preferentially expressed in retina was obtained by integrating expressed sequence tag, SAGE and microarray datasets. The regulatory targets of retina-specific TFs are enriched in this set of retina-related genes. A Bayesian approach was employed to integrate information about binding site location relative to a gene's transcription start site. Our method was applied to three retina-specific TFs, CRX, NRL and NR2E3, and a number of potential targets were predicted. To experimentally assess the validity of the bioinformatic predictions, mobility shift, transient transfection and chromatin immunoprecipitation assays were performed with five predicted CRX targets, and the results were suggestive of CRX regulation in 5/5, 3/5 and 4/5 cases, respectively. Together, these experiments strongly suggest that RP1, GUCY2D, ABCA4 are novel targets of CRX

Automated Meet-in-the-Middle Attack Goes to Feistel

Feistel network and its generalizations (GFN) are another important building blocks for constructing hash functions, e.g., Simpira v2, Areion, and the ISO standard Lesamnta-LW. The Meet-in-the-Middle (MitM) is a general paradigm to build preimage and collision attacks on hash functions, which has been automated in several papers. However, those automatic tools mostly focus on the hash function with Substitution-Permutation network (SPN) as building blocks, and only one for Feistel network by Schrottenloher and Stevens (at CRYPTO 2022). In this paper, we introduce a new automatic model for MitM attacks on Feistel networks by generalizing the traditional direct or indirect partial matching strategies and also Sasaki’s multi-round matching strategy. Besides, we find the equivalent transformations of Feistel and GFN can significantly simplify the MILP model. Based on our automatic model, we improve the preimage attacks on Feistel-SP-MMO, Simpira-2/-4-DM, Areion-256/-512-DM by 1-2 rounds or significantly reduce the complexities. Furthermore, we fill in the gap left by Schrottenloher and Stevens at CRYPTO 2022 on the large branch (b > 4) Simpira-b’s attack and propose the first 11-round attack on Simpira-6. Besides, we significantly improve the collision attack on the ISO standard hash Lesamnta-LW by increasing the attacked round number from previous 11 to ours 17 rounds

Molecular Characterization and Tissue Localization of an F-Box Only Protein from Silkworm, Bombyx mori

The eukaryotic F-box protein family is characterized by an F-box motif that has been shown to be critical for the controlled degradation of regulatory proteins. We identified a gene encoding an F-box protein from a cDNA library of silkworm pupae, which has an ORF of 1821 bp, encoding a predicted 606 amino acids. Bioinformatic analysis on the amino acid sequence shows that BmFBXO21 has a low degree of similarity to proteins from other species, and may be related to the regulation of cell-cycle progression. We have detected the expression pattern of BmFBXO21 mRNA and protein and performed immunohistochemistry at three different levels. Expression was highest in the spinning stage, and in the tissues of head, epidermis, and genital organs

Case Report: A novel de novo variant of COL1A1 in fetal genetic osteogenesis imperfecta

ObjectiveOsteogenesis imperfecta (OI) is a rare genetic disorder. Clinical severity is heterogeneous. The purpose of this study was to investigate the genetic characteristics of a fetus with OI by whole exome sequencing (WES) and identify the cause of the disease.MethodsIn this study, a fetus with osteogenic dysplasia was referred to our hospital. DNA was extracted from the aborted fetal tissue and peripheral blood of the parents. To identify the pathogenic genes, we conducted the trio-WES using DNA. A de novo variant in the COL1A1 gene is suspected to be the cause of the OI phenotype. We used Sanger sequencing for validation and various bioinformatics methods (such as SIFT, PolyPhen2, Mutation Taster, conservative analysis, SWISS Model, glycosylation site prediction, and I-Mutant 2.0) for analysis.ResultsBoth WES and Sanger sequencing identified a novel de novo variant of COL1A1 (c. 1309G>A, p. Gly437Ser) in a fetus with OI. Bioinformatic analysis showed that the affected residue, p. Gly437, was highly conserved in multiple species and predicted that the variant was deleterious and may have an impact on protein function. This variant is present in highly conserved glycine residues of Gly-X-Y sequence repeats of the triple helical region of the collagen type I α chain, which may be the cause of OI.ConclusionThis study revealed that the c.1309G>A (p. Gly437Ser) variant in the COL1A1 gene may be the genetic cause of fetal OI in this case. The discovery of this variant enriched the variation spectrum of OI. WES improves the accurate diagnosis of fetal OI, and doctors can provide patients with appropriate genetic counseling

A novel hybrid machine learning model for auxiliary diagnosing myocardial ischemia

IntroductionAccurate identification of the myocardial texture features of fat around the coronary artery on coronary computed tomography angiography (CCTA) images are crucial to improve clinical diagnostic efficiency of myocardial ischemia (MI). However, current coronary CT examination is difficult to recognize and segment the MI characteristics accurately during earlier period of inflammation.Materials and methodsWe proposed a random forest model to automatically segment myocardium and extract peripheral fat features. This hybrid machine learning (HML) model is integrated by CCTA images and clinical data. A total of 1,316 radiomics features were extracted from CCTA images. To further obtain the features that contribute the most to the diagnostic model, dimensionality reduction was applied to filter features to three: LNS, GFE, and WLGM. Moreover, statistical hypothesis tests were applied to improve the ability of discriminating and screening clinical features between the ischemic and non-ischemic groups.ResultsBy comparing the accuracy, recall, specificity and AUC of the three models, it can be found that HML had the best performance, with the value of 0.848, 0.762, 0.704 and 0.729.ConclusionIn sum, this study demonstrates that ML-based radiomics model showed good predictive value in MI, and offer an enhanced tool for predicting prognosis with greater accuracy