26 research outputs found

    OFAUMP: Ontology-based Framework for Adaptable User and Multimedia Presentations

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    International audienceThe application of Semantic Web technology brings an unprecedented opportunity and a challenge to Multimedia Web-based Information Systems (MWIS) [6]. This paper presents an ontology-based framework (OFAUMP), focusing on the coupling of the dynamic presentation model and user model that are the main components of MWIS, in the environment of the Semantic Web. In OFAUMP, Private ontology (i.e. user profile), transferred between user terminal devices and a special server, is automatically constructed for each user and shared by web sites/applications in order to realize user adaptation. We optimize Geurts [3] approach to automatically and intelligently generate multimedia presentation with the redefined domain, discourse and media knowledge. To combine the two models mentioned above, a new ontology is introduced, where usable resource for each kind of user and user’s route are described. This framework achieves the aims of dynamically selecting and presenting the multimedia data according to user profile in the Semantic Web

    OFAUMP: Ontology-based Framework for Adaptable User and Multimedia Presentations

    No full text
    International audienceThe application of Semantic Web technology brings an unprecedented opportunity and a challenge to Multimedia Web-based Information Systems (MWIS) [6]. This paper presents an ontology-based framework (OFAUMP), focusing on the coupling of the dynamic presentation model and user model that are the main components of MWIS, in the environment of the Semantic Web. In OFAUMP, Private ontology (i.e. user profile), transferred between user terminal devices and a special server, is automatically constructed for each user and shared by web sites/applications in order to realize user adaptation. We optimize Geurts [3] approach to automatically and intelligently generate multimedia presentation with the redefined domain, discourse and media knowledge. To combine the two models mentioned above, a new ontology is introduced, where usable resource for each kind of user and user’s route are described. This framework achieves the aims of dynamically selecting and presenting the multimedia data according to user profile in the Semantic Web

    In situ/operando characterization techniques to probe the electrochemical reactions for energy conversion

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    The water‐splitting reaction, including the hydrogen and oxygen evolution reactions, as well as the electrochemical oxygen and CO2 reduction reactions offer promising solutions to address the global energy scarcity and the associated environmental issues. However, the lack of deep insight into the reaction mechanisms and clear identification of the catalytic active sites hinder any breakthrough for the development of efficient electrocatalysts with high performance and durability. Operando characterization techniques allowing in situ monitoring the surface oxidation state and local atomic‐structure transformation are capable of probing the active sites and promoting the fundamental understanding of the reaction mechanism in these systems. Herein, the recent applications of various operando characterization techniques in identifying the active sites and capturing the geometric structure, oxidation state, and local atomic‐structure evolution of the catalysts during water electrolysis and O2/CO2 electroreduction are thoroughly summarized. The challenges and outlook in developing operando techniques to further extend the understanding of the underlying mechanism during electrochemical energy‐conversion reactions are discussed

    Pollution Characteristics and Human Health Risks of Elements in Road Dust in Changchun, China

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    Road dust, which contains trace elements and certain organic matter that can be harmful to human health, plays an important role in atmospheric pollution. In this paper, concentrations of 16 elements in the road dust of Changchun, China were determined experimentally. A total of 100 samples were collected using plastic brushes and dustpans, and the elements were analyzed by an inductively coupled plasma optical emission spectrometer (ICP-OES). It was indicated that the elements could be divided into major and trace elements. The concentration of trace elements followed the trend: mercury (Hg) > manganese (Mn) > zinc (Zn) > lead (Pb) > chromium (Cr) > copper (Cu) > vanadium (V) > arsenic (As) > nickel (Ni) > cobalt (Co) > cadmium (Cd). Contamination-level-assessment calculated by the geo-accumulation index (Igeo) showed that the pollution-level ranged from non-contaminated to extreme contamination, while the calculations of enrichment factor (EF) showed that EF values exhibited a decreasing trend: Cd > Hg > As > Pb > Cu > Co > Zn > Ni > Cr > V > Mn > Mg > Fe > Sr > Ba. In our study, ingestion was the greatest exposure pathway for humans to intake trace elements by calculating the average daily dose (ADD) from three routes (ingestion, inhalation, and dermal contact). According to the health risk assessment results, the non-carcinogenic risks that human beings suffered from these elements were insignificant. Additionally, the hazard quotient (HQ) values were approximately one-tenth in the case of children. Meanwhile, the total excess cancer risk (ECR) was also lower than the acceptable level (10−6–10−4) for both adults and children

    A Zero-Cross Detection Algorithm for Cavity-Length Interrogation of Fiber-Optic Fabry–Perot Sensors

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    A zero-cross detection algorithm was proposed for the cavity-length interrogation of fiber-optic Fabry–Perot (FP) sensors. The method can avoid the inaccuracy of peak determination in the conventional peak-to-peak method for the cavity-length interrogation of fiber-optic FP sensors caused by the slow variation of the spectral power density in peak neighboring regions. Both simulations and experiments were carried out to investigate the feasibility and performance of the zero-cross detection algorithm. Fiber-optic FP sensors with cavity lengths in the range of 150–1000 μm were successfully interrogated with a maximum error of 0.083 μm

    Low thermal expansion metal composite-based heat spreader for high temperature thermal management

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    The electronic industry is facing pressing needs for cooling system with high-performance in heat transfer and matched coefficient of thermal expansion (CTE) with the chips. Metal composite materials (MCMs) with low CTE can be used in cooling chips to overcome the thermal expansion mismatch between the cooling substrate and chips. However, low thermal conductivity of MCMs limits their application in electronic cooling systems. Increasing the percentage of components with high thermal conductivity can enhance the thermal conductivity of MCMs, but it often leads to increase CTE as well. Here, we demonstrate that vapor–liquid phase change can improve the heat transfer performance of tungsten-copper (W-Cu) alloy-based MCMs while maintain their low CTEs. Such strategy reduces the maximum temperature and thermal resistance of MCMs, and also allows for heat spreading from concentrated heat source with high power density. The W-Cu alloy-based vapor chamber (VC) has low thermal resistance of 0.38 K/W at 100 W and high lateral thermal conductivity of ~1727 W/(m·K). The W-Cu alloy-based VC can be readily integrated with the chip and heat sink to serve as cooling substrates for dissipating the heat and simultaneously lowering the thermal expansion mismatch by using its high thermal conductivity and low CTE

    Identifying active sites of nitrogen-doped carbon materials for the CO2 reduction reaction

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    Nitrogen-doped carbon materials are proposed as promising electrocatalysts for the carbon dioxide reduction reaction (CRR), which is essential for renewable energy conversion and environmental remediation. Unfortunately, the unclear cognition on the CRR active site (or sites) hinders further development of high-performance electrocatalysts. Herein, a series of 3D nitrogen-doped graphene nanoribbon networks (N-GRW) with tunable nitrogen dopants are designed to unravel the site-dependent CRR activity/selectivity. The N-GRW catalyst exhibits superior CO2 electrochemical reduction activity, reaching a specific current of 15.4 A gcatalyst−1 with CO Faradaic efficiency of 87.6% at a mild overpotential of 0.49 V. Based on X-ray photoelectron spectroscopy measurements, it is experimentally demonstrated that the pyridinic N site in N-GRW serves as the active site for CRR. In addition, the Gibbs free energy calculated by density functional theory further illustrates the pyridinic N as a more favorable site for the CO2 adsorption, *COOH formation, and *CO removal in CO2 reduction.NRF (Natl Research Foundation, S’pore)ASTAR (Agency for Sci., Tech. and Research, S’pore)MOE (Min. of Education, S’pore

    TyG Index Performs Better Than HOMA-IR in Chinese Type 2 Diabetes Mellitus with a BMI < 35 kg/m2: A Hyperglycemic Clamp Validated Study

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    Background and objectives: Chinese type 2 diabetes mellitus (T2DM) patients are characterized by a low body mass index (BMI), and significant insulin resistance (IR). The triglyceride glucose (TyG) index has not been studied as a means of assessing IR in Chinese T2DM patients with a BMI < 35 kg/m2. Materials and Methods: An open-label cross-sectional study recruited 102 Chinese T2DM patients with a BMI < 35 kg/m2. The hyper-insulinemic euglycemic clamp, homeostatic model assessment of IR (HOMA-IR), and TyG index were used to determine the level of IR. Based on Pearson’s correlations, glucose disposal rate (GDR), TyG index, and HOMA-IR were analyzed. HOMA-IR and TyG index for IR were evaluated using multiple linear regression and multivariate logistic regression analyses. On the basis of the receiver operating characteristic (ROC) curve, the sensitivity, specificity, and optimal cut-off value of HOMA-IR and the TyG index were determined. Results: The mean values of GDR, HOMA-IR, and TyG index were 4.25 ± 1.81, 8.05 ± 7.98, and 8.12 ± 0.86 mg/kg/min, respectively. Pearson’s correlation coefficient was −0.418 between GDR and TyG index and −0.324 between GDR and HOMA-IR. ROC curve analysis showed that, among both sexes, the TyG index was a better discriminator of IR than HOMA-IR. The area under the ROC curve (AUC) of the TyG index (0.785, 0.691–0.879) was higher than that of HOMA-IR (0.73, 0.588–0.873) in all genders. The optimal cut-off values of the TyG index and HOMA-IR were 7.99 and 3.39, respectively. Conclusions: The TyG index showed more effectiveness in identifying IR in Chinese T2DM patients with a BMI < 35 kg/m2 compared to HOMA-IR

    Targeting survivin with Tanshinone IIA inhibits tumor growth and overcomes chemoresistance in colorectal cancer

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    Abstract The inhibitor of apoptosis protein survivin has a critical regulatory role in carcinogenesis and treatment tolerance in colorectal cancer (CRC). However, the targeted drugs for survivin protein are extremely limited. In the present research, we discovered that Tanshinone IIA (Tan IIA) played a dual regulatory role in inhibiting tumorigenesis and reversing 5-Fu tolerance via modulating the expression and phosphorylation of survivin in CRC cells. Mechanistically, Tan IIA suppressed the Akt/WEE1/CDK1 signaling pathway, which led to the downregulation of survivin Thr34 phosphorylation and destruction of the interaction between USP1 and survivin to promote survivin ubiquitination and degradation. Furthermore, Tan IIA significantly facilitated chemoresistant CRC cells to 5-Fu sensitivity. These results revealed that Tan IIA possessed a strong antitumor activity against CRC cells and could act as an up-and-coming agent for treating CRC and overcoming chemotherapy resistance
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