23 research outputs found

    Graph-Level Embedding for Time-Evolving Graphs

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    Graph representation learning (also known as network embedding) has been extensively researched with varying levels of granularity, ranging from nodes to graphs. While most prior work in this area focuses on node-level representation, limited research has been conducted on graph-level embedding, particularly for dynamic or temporal networks. However, learning low-dimensional graph-level representations for dynamic networks is critical for various downstream graph retrieval tasks such as temporal graph similarity ranking, temporal graph isomorphism, and anomaly detection. In this paper, we present a novel method for temporal graph-level embedding that addresses this gap. Our approach involves constructing a multilayer graph and using a modified random walk with temporal backtracking to generate temporal contexts for the graph's nodes. We then train a "document-level" language model on these contexts to generate graph-level embeddings. We evaluate our proposed model on five publicly available datasets for the task of temporal graph similarity ranking, and our model outperforms baseline methods. Our experimental results demonstrate the effectiveness of our method in generating graph-level embeddings for dynamic networks.Comment: In Companion Proceedings of the ACM Web Conference 202

    Embedding Heterogeneous Networks into Hyperbolic Space Without Meta-path

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    Networks found in the real-world are numerous and varied. A common type of network is the heterogeneous network, where the nodes (and edges) can be of different types. Accordingly, there have been efforts at learning representations of these heterogeneous networks in low-dimensional space. However, most of the existing heterogeneous network embedding methods suffer from the following two drawbacks: (1) The target space is usually Euclidean. Conversely, many recent works have shown that complex networks may have hyperbolic latent anatomy, which is non-Euclidean. (2) These methods usually rely on meta-paths, which require domain-specific prior knowledge for meta-path selection. Additionally, different down-streaming tasks on the same network might require different meta-paths in order to generate task-specific embeddings. In this paper, we propose a novel self-guided random walk method that does not require meta-path for embedding heterogeneous networks into hyperbolic space. We conduct thorough experiments for the tasks of network reconstruction and link prediction on two public datasets, showing that our model outperforms a variety of well-known baselines across all tasks.Comment: In proceedings of the 35th AAAI Conference on Artificial Intelligenc

    Non-syndromic enlarged vestibular aqueduct caused by novel compound mutations of the SLC26A4 gene: a case report and literature review

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    Enlarged vestibular aqueduct is an autosomal genetic disease mainly caused by mutations in the SLC26A4 gene and includes non-syndromic and syndromic types. This study aimed to identify genetic defects in a Chinese patient with non-syndromic enlarged vestibular aqueduct (NSEVA) and to investigate the impact of variants on the severity of non-syndromic enlarged vestibular aqueduct. A male patient with NSEVA, aged approximately 6 years, was recruited for this study. The clinical characteristics and results of auxiliary examinations, including laboratory and imaging examinations, were collected, and 127 common hereditary deafness genes were detected by chip capture high-throughput sequencing. Protein structure predictions, the potential impact of mutations, and multiple sequence alignments were analyzed in silico. Compound heterozygote mutations c.1523_1528delinsAC (p.Thr508Asnfs*3) and c.422T>C (p.Phe141Ser) in the SLC26A4 gene were identified. The novel frameshift mutation c.1523_1528delinsAC produces a severely truncated pendrin protein, and c.422T>C has been suggested to be a disease-causing mutation. Therefore, this study demonstrates that the novel mutation c.1523_1528delinsAC in compound heterozygosity with c.422T>C in the SLC26A4 gene is likely to be the cause of NSEVA. Cochlear implants are the preferred treatment modality for patients with NSEVA and severe-to-profound sensorineural hearing loss Genetic counseling and prenatal diagnosis are essential for early diagnosis. These findings expand the mutational spectrum of SLC26A4 and improve our understanding of the molecular mechanisms underlying NSEVA

    Geology, U-Pb geochronology and stable isotope geochemistry of the Heihaibei gold deposit in the southern part of the Eastern Kunlun Orogenic Belt, China : A granitic intrusion-related gold deposit?

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    The Heihaibei gold deposit is a newly discovered gold deposit in the southern part of the Eastern Kunlun Orogenic Belt. Its most distinctive features are that the gold mineralization is hosted in monzogranite, and that the presence of pre-ore (possibly syn-ore) monzogranite and post-ore gabbro allows to constrain the minerali-zation's formation age. Zircons from the monzogranites yield U-Pb ages of 454 +/- 3 Ma, while zircons separated from the gabbro dikes cutting the monzogranites and gold mineralized body yield U-Pb ages of 439 +/- 3 Ma, which is interpreted to be the minimum age of the Au mineralizing event. Combined with the regional geological background, we proposed that the Heihaibei Au mineralization occurred during the subduction stage of the Early Paleozoic Proto-Tethys ocean. The ore assemblage is dominated by pyrite, arsenopyrite and native gold. The hydrothermal alteration that has led to the peculiar enrichment of Au is not systematically distributed and displays no clear concentric zoning pattern. The main mineralization formed during three stages: the K-feldspar-quartz-pyrite (Py1)-arsenopyrite-sericite-epidote stage (I), the quartz-pyrite (Py2)-native gold-chlorite stage (II), and the quartz-carbonate stage (III). The main gold mineralization occurred during stage II. Fluid inclusion homogenization temperature and salinities decrease from stage I (Th., 268-412 C; W., 6.87-16.63 wt% NaCl equiv.) to stage II (Th., 183-288 C; W., 3.69-14.84 wt% NaCl equiv.). The 818O and 8D values (818OH2O = 4.9 to 9.7%o; 8DV-SMOW =-84.1%o to -81.1%o) of quartz samples from stage I and stage II are comparable to a magmatic-hydrothermal ore-forming fluid that possibly underwent fluid-rock interaction with the Nachitai Group metamorphic rocks during the early ore-forming stage. The relatively uniform 834S values (834SV-CDT = 7.7 to 8.5%o) are slightly elevated compared to magmatic 834S values, but could be derived from a magma if a significant crustal melt component is present. Moreover, the 834S values are within the S isotopic composition range of a granitic reservoir, suggesting that they are probably inherited from the Heihaibei monzogranites. The Pb and Hf isotope compositions imply a close genetic association between the gold mineralization and granitic magmatism, which are both the products of the mixing of crustal and mantle sources. The trace element compositions of pyrite provide additional evidence that the gold mineralization in the Heihaibei deposit was related to the magmatism. Compared with the typical characteristics of orogenic gold and intrusion-related gold systems (IRGS) deposits, the Heihaibei gold deposit may instead be classified as a granitic intrusion-related gold deposit.Peer reviewe

    Forecasting Realized Volatility of Agricultural Commodities

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    We forecast the realized and median realized volatility of agricultural commodities using variants of the Heterogeneous AutoRegressive (HAR) model. We obtain tick-by-tick data for five widely traded agricultural commodities (Corn, Rough Rice, Soybeans, Sugar, and Wheat) from the CME/ICE. Real out-of-sample forecasts are produced for 1- up to 66-days ahead. Our in-sample analysis shows that the variants of the HAR model which decompose volatility measures into their continuous path and jump components and incorporate leverage effects offer better fitting in the predictive regressions. However, we convincingly demonstrate that such HAR extensions do not offer any superior predictive ability in the out-of-sample results, since none of these extensions produce significantly better forecasts compared to the simple HAR model. Our results remain robust even when we evaluate them in a Value-at-Risk framework. Thus, there is no benefit by adding more complexity, related to volatility decomposition or relative transformations of volatility, in the forecasting models

    Effectiveness of celebrity endorsement on high and low involvement products

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    Celebrity endorsement is a common advertising method in Singapore whereby all kinds of products are featured. The purpose of this research study is to examine two issues- whether celebrity or non-celebrity endorsement is more effective in increasing purchase intention and affect towards product featured; and whether celebrity endorsement is more effective in driving purchase intention and affect for high or low involvement products. Based on past studies and literature reviews, three hypotheses were proposed. Two pre-tests were set up to determine the particular products, celebrities and their fictitious brand names. These were used in the core research study that followed; 2 sets of questions were used to measure respondents’ purchase intention and affect after viewing each self-created, product-specific print advertisements that featured either the selected celebrity or other non-celebrity endorsers. The target respondents were young adults aged 18-24, and the pre-tests and core research stages were conducted via online surveys. The results concluded that celebrity endorsement resulted in a significantly higher purchase intention and affect towards the product featured, as compared to non-celebrity endorsement. Celebrity endorsement is also more effective in increasing purchase intention and affect for high involvement products as compared to low involvement products. The research finding can enable marketeers to allocate their marketing budget more efficiently, especially in times of recession, which will aid them in devising more effective marketing efforts.BUSINES

    The Structure, Expression, and Function Prediction of DAZAP2, A Down-Regulated Gene in Multiple Myeloma

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    In our previous studies, DAZAP2 gene expression was down-regulated in untreated patients of multiple myeloma (MM). For better studying the structure and function of DAZAP2, a full-length cDNA was isolated from mononuclear cells of a normal human bone marrow, sequenced and deposited to Genbank (AY430097). This sequence has an identical ORF (open reading frame) as the NM_014764 from human testis and the D31767 from human cell line KG-1. Phylogenetic analysis and structure prediction reveal that DAZAP2 homologues are highly conserved throughout evolution and share a polyproline region and several potential SH2/SH3 binding sites. DAZAP2 occurs as a single-copy gene with a four-exon organization. We further noticed that the functional DAZAP2 gene is located on Chromosome 12 and its pseudogene gene is on Chromosome 2 with electronic location of human chromosome in Genbank, though no genetic abnormalities of MM have been reported on Chromosome 12. The ORF of human DAZAP2 encodes a 17-kDa protein, which is highly similar to mouse Prtb. The DAZAP2 protein is mainly localized in cytoplasm with a discrete pattern of punctuated distribution. DAZAP2 may associate with carcinogenesis of MM and participate in yet-to-be identified signaling pathways to regulate proliferation and differentiation of plasma cells

    Preparation and Modification of Rape Straw Biochar and Its Adsorption Characteristics for Methylene Blue in Water

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    To solve the double problems of methylene blue (MB) pollution in water and waste of straw resources, rape straw biochar (RSB600) was made by thermal decomposition of discarded rape residues at 600 °C, and modified RSB600(M-RSB600) was prepared after treatment with NaOH for MB adsorption. The physicochemical properties, MB adsorption properties and mechanism of RSB600 and M-RSB600 were studied. According to the experimental findings, M-RSB600 has stronger aromaticity, higher hydrophilicity, and more polarity than RSB600. Under the same adsorption conditions, M-RSB600 obtained better MB adsorption effect with less dosage. The MB equilibrium adsorption capacity of M-RSB600 reached 268.46 mg/g, which was 65.6% higher than that of RSB600. The quasi-second-order kinetic model better described the adsorption kinetics of MB on RSB600 and M-RSB600 (R2 > 0.98), and the Freundlich and Temkin models better described the adsorption isotherms (R2 > 0.95). The adsorption process was spontaneous, internal heat and entropy driven multilayer adsorption, dominated by chemical adsorption, specifically involving multiple interaction mechanisms, including electrostatic adherence, hydrogen-bond, π-π bond and ion-exchange. The results demonstrated that NaOH modification obviously improved the structure of RSB and make it had better adsorption and regeneration performance. M-RSB600 can be utilized as the ideal substance for effectively removing MB from effluent

    Preparation and Modification of Rape Straw Biochar and Its Adsorption Characteristics for Methylene Blue in Water

    No full text
    To solve the double problems of methylene blue (MB) pollution in water and waste of straw resources, rape straw biochar (RSB600) was made by thermal decomposition of discarded rape residues at 600 °C, and modified RSB600(M-RSB600) was prepared after treatment with NaOH for MB adsorption. The physicochemical properties, MB adsorption properties and mechanism of RSB600 and M-RSB600 were studied. According to the experimental findings, M-RSB600 has stronger aromaticity, higher hydrophilicity, and more polarity than RSB600. Under the same adsorption conditions, M-RSB600 obtained better MB adsorption effect with less dosage. The MB equilibrium adsorption capacity of M-RSB600 reached 268.46 mg/g, which was 65.6% higher than that of RSB600. The quasi-second-order kinetic model better described the adsorption kinetics of MB on RSB600 and M-RSB600 (R2 > 0.98), and the Freundlich and Temkin models better described the adsorption isotherms (R2 > 0.95). The adsorption process was spontaneous, internal heat and entropy driven multilayer adsorption, dominated by chemical adsorption, specifically involving multiple interaction mechanisms, including electrostatic adherence, hydrogen-bond, π-π bond and ion-exchange. The results demonstrated that NaOH modification obviously improved the structure of RSB and make it had better adsorption and regeneration performance. M-RSB600 can be utilized as the ideal substance for effectively removing MB from effluent
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