Voucher Abuse Detection with Prompt-based Fine-tuning on Graph Neural Networks

Voucher abuse detection is an important anomaly detection problem in E-commerce. While many GNN-based solutions have emerged, the supervised paradigm depends on a large quantity of labeled data. A popular alternative is to adopt self-supervised pre-training using label-free data, and further fine-tune on a downstream task with limited labels. Nevertheless, the "pre-train, fine-tune" paradigm is often plagued by the objective gap between pre-training and downstream tasks. Hence, we propose VPGNN, a prompt-based fine-tuning framework on GNNs for voucher abuse detection. We design a novel graph prompting function to reformulate the downstream task into a similar template as the pretext task in pre-training, thereby narrowing the objective gap. Extensive experiments on both proprietary and public datasets demonstrate the strength of VPGNN in both few-shot and semi-supervised scenarios. Moreover, an online deployment of VPGNN in a production environment shows a 23.4% improvement over two existing deployed models.Comment: 7 pages, Accepted by CIKM23 Applied Research Trac

Size measurement of dry ice particles produced from liquid carbon dioxide

The formation of dry ice particles in a jet flow has been studied experimentally. The particles were produced by rapid expansion of liquid carbon dioxide through a nozzle, based on the Joule–Thomson effect. Their size distribution was measured by a laser diffraction method. The experimental results showed that the primary dry ice particles ejected from the nozzle were about 1 μm in mass median diameter. However, they grew initially in the jet flow and then became smaller due to sublimation. As a result, a bimodal size distribution was formed at increased distances from the nozzle outlet. The presence of a thermally insulated tube at the outlet of the expansion nozzle enhanced the agglomeration of the particles, whereby agglomerates of about 100 μm in mass median diameter were recorded. The agglomeration process is considered to take place by the simultaneous processes of particle deposition and reentrainment; i.e. agglomerated particles are reentrained from the layer of dry ice particles deposited on the tube walls. The agglomerate size decreased with increasing flow velocity, due to the greater detachment force applied to the deposition layer. Therefore, the flow velocity was found to be an important parameter influencing the agglomeration of dry ice particles

High mobility group box 1 complexed with heparin induced angiogenesis in a matrigel plug assay

Angiogenesis involves complex processes mediated by several factors and is associated with inflammation and wound healing. High mobility group box 1 (HMGB1) is released from necrotic cells as well as macrophages and plays proinflammatory roles. In the present study, we examined whether HMGB1 would exhibit angiogenic activity in a matrigel plug assay in mice. HMGB1 in combination with heparin strongly induced angiogenesis, whereas neither HMGB1 nor heparin alone showed such angiogenic activity. The heparin-dependent induction of angiogenesis by HMGB1 was accompanied by increases in the expression of tumor necrosis factor-alpha (TNF-alpha) and vascular endothelial growth factor-A120 (VEGF-A120). It is likely that the dependence of the angiogenic activity of HMGB1 on heparin was due to the efficiency of the diffusion of the HMGB1-heparin complex from matrigel to the surrounding areas. VEGF-A165 possessing a heparin-binding domain showed a pattern of heparin-dependent angiogenic activity similar to that of HMGB1. The presence of heparin also inhibited the degradation of HMGB1 by plasmin in vitro. Taken together, these results suggested that HMGB1 in complex with heparin possesses remarkable angiogenic activity, probably through the induction of TNF-alpha and VEGF-A120.</p

Numbers of Publications Related to Laboratory Animals

Laboratory animals are widely utilized in biomedical research, so a search of scientific publications can  give us useful information on the use of animals. We retrieved the PubMed biomedicine database and  searched for publications related to laboratory animals from 1966 to 2005. We found that rats and mice  constitute the vast majority of species used in biomedical research; C57BL and BABL/c inbred mice, and  Sprague Dawley and Wistar outbred rats are the most common strains. Recently, the numbers of publications  relating to traditionally used animals such as rats, guinea pigs, dogs, cats, and sheep decreased slightly,  whereas the numbers relating to mice, fish, Drosophila and Caenorhabditis elegans increased from 1995  to 2005, with annual mean growth rates of 4.5%, 8.22%, 1.95%, and 10.3%, respectively. Publications  involving transgenic mice increased dramatically from the mid-1980s. This survey provides significant  clues for predicting the future direction of biomedical research.

Establishment of in Vitro Binding Assay of High Mobility Group Box-1 and S100A12 to Receptor for Advanced Glycation Endproducts: Heparin's Effect on Binding

Interaction between the receptor for advanced glycation end products (RAGE) and its ligands has been implicated in the pathogenesis of various inflammatory disorders. In this study, we establish an in vitro binding assay in which recombinant human high-mobility group box 1 (rhHMGB1) or recombinant human S100A12 (rhS100A12) immobilized on the microplate binds to recombinant soluble RAGE (rsRAGE). The rsRAGE binding to both rhHMGB1 and rhS100A12 was saturable and dependent on the immobilized ligands. The binding of rsRAGE to rhS100A12 depended on Ca2 and Zn2, whereas that to rhHMGB1 was not. Scatchard plot analysis showed that rsRAGE had higher affinity for rhHMGB1 than for rhS100A12. rsRAGE was demonstrated to bind to heparin, and rhS100A12, in the presence of Ca2, was also found to bind to heparin. We examined the effects of heparin preparations with different molecular sizesunfractionated native heparin (UFH), low molecular weight heparin (LMWH) 5000Da, and LMWH 3000Da on the binding of rsRAGE to rhHMGB1 and rhS100A12. All 3 preparations concentration-dependently inhibited the binding of rsRAGE to rhHMGB1 to a greater extent than did rhS100A12. These results suggested that heparin's anti-inflammatory effects can be partly explained by its blocking of the interaction between HMGB1 or S100A12 and RAGE. On the other hand, heparin would be a promising effective remedy against RAGE-related inflammatory disorders.</p

Factors Influencing the Number of Eggs Recovered from Rabbits Superovulated with FSH or PMSG: Analysis of Five Years of Data from 509 Rabbits

To determine the best conditions for superovulation in rabbits, we analyzed the influence of age, season and hormone treatment on the numbers of eggs collected over five years from 509 rabbits aged 4–10 months using follicular stimulating hormone (FSH) or pregnant mare serum gonadotropin (PMSG) hormone stimulation. The number of eggs recovered was significantly higher in younger rabbits in both treated groups (P &lt; 0.01–0.05). The number of eggs collected from rabbits treated with FSH were significantly higher than from rabbits treated with PMSG at all ages (P &lt; 0.01). Seasonal differences were not observed in either hormone treatment group as they were maintained under constant temperature, humidity and light cycle through the year. Thus, younger rabbits are more sensitive to hormonal superovulation treatment with both FSH and PMSG, and FSH offers a better regimen for egg collection

Effect of the primary cooling rate on the motility and fertility of frozen-thawed rabbit spermatozoa

[EN] In the present study, we examined the effect of primary cooling rates on the motility and fertility of frozen-thawed rabbit spermatozoa. Rabbit semen diluted with an egg-yolk acetamide extender was cooled from room temperature to 5°C at four different rates (-0.1, -0.2, -0.4, -0.8°C/min) as a primary cooling step, then semen was frozen in liquid nitrogen vapour. After thawing, sperm cooled at -0.1°C/min showed the highest motility (40.7 ± 7.3%); there were no significant differences between the motilities of the -0.1, -0.2, and -0.4°C/min groups. The motility of frozen-thawed sperm cooled at -0.8°C/min (29.2 ± 6.8%) was significantly lower than that of sperm cooled at -0.1 and -0.2°C/min. The viability (-0.1°C/min, 38.1 ± 4.0%; -0.8°C/min, 24.3 ± 7.3%) of frozen-thawed sperm was closely related to its motility (-0.1°C/min, 36.7 ± 7.2%; -0.8°C/min, 22.3 ± 4.7%). Quality of post-thaw motile sperm cooled at different rates was estimated by comparing the fertilisation ability of the -0.1 and -0.8°C/min groups following artificial insemination. There were no significant differences in pregnancy rates and mean litter sizes. These data suggest that cooling rabbit semen at rates ranging from -0.1 to -0.8°C/min affects the viability but not the fertilisation capacity of motile spermatozoa after thawing.The authors thank Ms. T. Shimazaki, Ms. R. Tsuneyoshi, and Ms. R. Eriguchi for their technical assistance. This study was partly supported by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (No. 22500386).Maeda, T.; Liu, E.; Nishijima, K.; Tanaka, M.; Yamaguchi, S.; Morimoto, M.; Watanabe, T.... (2012). Effect of the primary cooling rate on the motility and fertility of frozen-thawed rabbit spermatozoa. World Rabbit Science. 20(2):65-70. doi:10.4995/wrs.2012.1080SWORD657020

Histidine-Rich Glycoprotein Inhibits High-Mobility Group Box-1-Mediated Pathways in Vascular Endothelial Cells through CLEC-1A

High-mobility group box-1 (HMGB1) protein has been postulated to play a pathogenic role in severe sepsis. Histidine-rich glycoprotein (HRG), a 75 kDa plasma protein, was demonstrated to improve the survival rate of septic mice through the regulation of neutrophils and endothelium barrier function. As the relalionship of HRG and HMGB1 remains poorly understood, we investigated the effects of HRG on HMGB1-mediated pathway in endothelial cells, focusing on the involvement of specific receptors for HRG. HRC potently inhibited the HMGB1 mobilization and effectively suppressed rHMGB1-induced inflammatory responses and expression of all three HMGB1 receptors in endothelial cells. Moreover, we first clarified that these protective effects of HRG on endothelial cells were mediated through C-type lectin domain family 1 member A (CLEC-1A) receptor. Thus, current study elueiates protective effects of HRG on vascular endothelial cells through inhintion of HMGB1-mediated pathways may contribute to the therapeutic effects of HRG on severe sepsis