153 research outputs found

    A Service Composition Approach Based on Pre-joined Service Network in Graph Database

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    We solve the service composition problem with plugin semantic matching in a graph database. We present a Prejoined Service Network (PJSN) approach which firstly constructs and stores a service composition network with all services and compositions in a graph database. Then, this approach fetches a satisfying solution by converting the composition request into Cypher and querying the graph database. We evaluate the performance of the proposed PJSN approach by conducting experiments and comparing with that of the Pre-joined Semantic Indexing Graph (PJSIG) method. The experiment results show that compared with the PJSIG method, the proposed approach can always find a solution and lead to higher user’s satisfaction

    Research progress in cardiotoxicity of organophosphate esters

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    Organophosphate esters (OPEs) have been extensively utilized worldwide as a substitution for brominated flame retardants. With an increased awareness of the need for environmental protection, the potential health risks and ecological hazards of OPEs have attracted widespread attention. As the dynamic organ of the circulatory system, the heart plays a significant role in maintaining normal life activities. Currently, there is a lack of systematic appraisal of the cardiotoxicity of OPEs. This article summarized the effects of OPEs on the morphological structure and physiological functions of the heart. It is found that these chemicals can lead to pericardial edema, abnormal looping, and thinning of atrioventricular walls in the heart, accompanied by alterations in heart rate, with toxic effects varying by the OPE type. These effects are primarily associated with the activation of endoplasmic reticulum stress response, the perturbation of cytoplasmic and intranuclear signal transduction pathways in cardiomyocytes. This paper provides a theoretical basis for further understanding of the toxic effects of OPEs and contributes to environmental protection and OPEs’ ecological risk assessment

    SDF-1α/CXCR4 Axis Mediates The Migration of Mesenchymal Stem Cells to The Hypoxic-Ischemic Brain Lesion in A Rat Model

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    Objective: Transplantation of mesenchymal stem cells (MSCs) can promote functional recovery of the brain after hypoxic-ischemic brain damage (HIBD). However, the mechanism regulating MSC migration to a hypoxic-ischemic lesion is poorly understood. Interaction between stromal cell-derived factor-1α (SDF-1α) and its cognate receptor CXC chemokine receptor 4 (CXCR4) is crucial for homing and migration of multiple stem cell types. In this study, we investigate the potential role of SDF-1α/CXCR4 axis in mediating MSC migration in an HIBD model. Materials and Methods: In this experimental study, we first established the animal model of HIBD using the neonatal rat. Bone marrow MSCs were cultured and labeled with 5-bromo-21-deoxyuridine (BrdU) after which 6×106 cells were intravenously injected into the rat. BrdU positive MSCs in the hippocampus were detected by immunohistochemical analyses. The expression of hypoxia-inducible factor-1α (HIF-1α) and SDF-1α in the hippocampus of hypoxic-ischemic rats was detected by Western blotting. To investigate the role of hypoxia and SDF-1α on migration of MSCs in vitro, MSCs isolated from normal rats were cultured in a hypoxic environment (PO2=1%). Migration of MSCs was detected by the transwell assay. The expression of CXCR4 was tested using Western blotting and flow cytometry. Results: BrdU-labeled MSCs were found in the rat brain, which suggested that transplanted MSCs migrated to the site of the hypoxic-ischemic brain tissue. HIF-1α and SDF- 1α significantly increased in the hippocampal formations of HIBD rats in a time-dependent manner. They peaked on day 7 and were stably expressed until day 21. Migration of MSCs in vitro was promoted by SDF-1α under hypoxia and inhibited by the CXCR4 inhibitor AMD3100. The expression of CXCR4 on MSCs was elevated by hypoxia stimulation as well as microdosage treatment of SDF-1α. Conclusion: This observation illustrates that SDF-1α/CXCR4 axis mediate the migration of MSCs to a hypoxic-ischemic brain lesion in a rat model

    Memory-enhancing effect of Rhodiola rosea L extract on aged mice

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    Purpose: The memory-enhancing effects of Rhodiola rosea L. extract (RRLE) on normal aged mice were assessed.Methods: In the open-field test, the effect of RRLE (150 and 300 mg/kg) on mouse locomotive activities was evaluated by investigating the extract’s influence on CAT and AchE activities in the brain tissue of mice.Results: Compared with aged group, high dose of RRLE reduced the total distance (3212.4 ± 123.1 cm, p < 0.05) significantly, increased catalase (CAT) activity (101.4 ± 12.2 U/mg pro, p < 0.05), and inhibited acetyl cholinesterase (AChE) activity (0.94 ± 0.12 U/mg pro, p < 0.05) in the brain tissue of aged mice.Conclusion: The results show that RRLE improves the memory functions of aged mice probably by increasing CAT activity while decreasing AChE activity.Keywords: Rhodiola rosea, Memory function, Catalase, Acetyl cholinesterase, Open-field tes

    Tumor-Initiating Cells Are Enriched in CD44hi Population in Murine Salivary Gland Tumor

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    Tumor-initiating cells (T-ICs) discovered in various tumors have been widely reported. However, T-IC populations in salivary gland tumors have yet to be elucidated. Using the established Pleomorphic Adenoma Gene-1 (Plag1) transgenic mouse model of a salivary gland tumor, we identified CD44high (CD44hi) tumor cells, characterized by high levels of CD44 cell surface expression, as the T-ICs for pleomorphic adenomas. These CD44hi tumor cells incorporated 5-bromo-2-deoxyuridine (BrdU), at a lower rate than their CD44negative (CD44neg) counterparts, and also retained BrdU for a long period of time. Cell surface maker analysis revealed that 25% of the CD44hi tumor cells co-express other cancer stem cell markers such as CD133 and CD117. As few as 500 CD44hi tumor cells were sufficient to initiate pleomorphic adenomas in one third of the wildtype mice, whereas more than 1×104 CD44neg cells were needed for the same purpose. In NIH 3T3 cells, Plag1 was capable of activating the gene transcription of Egr1, a known upregulator for CD44. Furthermore, deletion of sequence 81–96 in the Egr1 promoter region abolished the effect of Plag1 on Egr1 upregulation. Our results establish the existence of T-ICs in murine salivary gland tumors, and suggest a potential molecular mechanism for CD44 upregulation

    The Impact of the Community Built Environment on the Walking Times of Residents in a Community in the Downtown Area of Fuzhou

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    By means of on-site and network investigation, we collected data relevant to residents of communities, point of interest (POI) data, and land-use data of Fuzhou. We set traffic walking time and leisure walking time as an independent variable, built environment as dependent variable, and gender, age, education level and income level as control variables. Six linear regression models were established using Statistical Product and Service Solutions (SPSS). The results showed that in the 5D (i.e., Density, Diversity, Design, Destination and Distance) elements of the built environment, the density was negatively correlated with the traffic walking time, whereas other elements were positively correlated with the walking time, but the degree of influence was different

    A review of causality-based fairness machine learning

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    With the wide application of machine learning driven automated decisions (e.g., education, loan approval, and hiring) in daily life, it is critical to address the problem of discriminatory behavior toward certain individuals or groups. Early studies focused on defining the correlation/association-based notions, such as statistical parity, equalized odds, etc. However, recent studies reflect that it is necessary to use causality to address the problem of fairness. This review provides an exhaustive overview of notions and methods for detecting and eliminating algorithmic discrimination from a causality perspective. The review begins by introducing the common causality-based definitions and measures for fairness. We then review causality-based fairness-enhancing methods from the perspective of pre-processing, in-processing and post-processing mechanisms, and conduct a comprehensive analysis of the advantages, disadvantages, and applicability of these mechanisms. In addition, this review also examines other domains where researchers have observed unfair outcomes and the ways they have tried to address them. There are still many challenges that hinder the practical application of causality-based fairness notions, specifically the difficulty of acquiring causal graphs and identifiability of causal effects. One of the main purposes of this review is to spark more researchers to tackle these challenges in the near future
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