190 research outputs found

    Digital breast tomosynthesis-based peritumoral radiomics approaches in the differentiation of benign and malignant breast lesions

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    PURPOSEWe aimed to evaluate digital breast tomosynthesis (DBT)-based radiomics in the differentiation of benign and malignant breast lesions in women.METHODSA total of 185 patients who underwent DBT scans were enrolled between December 2017 and June 2019. The features of handcrafted and deep learning-based radiomics were extracted from the tumoral and peritumoral regions with different radial dilation distances outside the tumor. A 3-step method was used to select discriminative features and develop the radiomics signature. Discriminative clinical factors were identified by univariate logistic regression. The clinical fac- tors with P < .05 were used to build a clinical model with multivariate logistic regression. The radiomics nomogram was developed by integrating the radiomics signature and discriminative clinical factors. Discriminative performance of the radiomics signature, clinical model, nomo- gram, and breast imaging reporting and data system assessment were evaluated and compared with the receiver operating characteristic and decision curves analysis (DCA).RESULTSA total of 2 handcrafted and 2 deep features were identified as the most discriminative features from the peritumoral regions with 2 mm dilation distances and used to develop the radiomics signature. The nomogram incorporating the radiomics signature, age, and menstruation status showed the best discriminative performance with area under the curve (AUC) values of 0.980 (95% CI, 0.960 to 1.000; sensitivity =0.970, specificity =0.946) in the training cohort and 0.985 (95% CI, 0.960 to 1.000; sensitivity = 0.909, specificity = 0.966) in the validation cohort. DCA con- firmed the potential clinical usefulness of our nomogram.CONCLUSIONOur results illustrate that the radiomics nomogram integrating the DBT imaging features and clinical factors (age and menstruation status) can be considered as a useful tool in aiding the clinical diagnosis of breast cancer

    An optical glucose biosensor fabricated by encapsulating glucose oxidase in silica gel via sol-gel method

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    Conference Name:2011 International Symposium on Advanced Packaging Materials, APM 2011. Conference Address: Xiamen, China. Time:October 25, 2011 - October 28, 2011.An optical glucose biosensor was fabricated by encapsulating glucose oxidase in TEOS-derived gel film along with Ru(bpy)3Cl2 as an luminescent oxygen transducer, for determining the concentration of glucose in the blood and urine samples. When the oxidation reaction of glucose by glucose oxidase occurred, an increase in the fluorescence intensity of Ru(bpy)3Cl2 was observed due to the oxygen consumption. A good response performance to glucose was exhibited for the biosensor with a wide linear range from 2.0 to 18.0mM, R=0.997. The detection limit of the biosensor was estimated to be 0.368mM, with response time < 50s. There was no apparent interference for the biosensor with fructose, urea and ascorbic acid. In addition, the enzymatic activity and long-term stability were also discussed in details. ? 2011 IEEE

    Potential of Core-Collapse Supernova Neutrino Detection at JUNO

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    JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

    Detection of the Diffuse Supernova Neutrino Background with JUNO

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    As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

    Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

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    Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30MM_{\odot} for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

    Corrosion Features of the Reinforcing Bar in Concrete with Intelligent OH− Regulation of Microcapsules

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    Corrosion is a challenging problem for marine concrete infrastructure projects. In this study, an intelligent OH&minus;-regulated microcapsule is designed to prevent reinforcement corrosion, taking ethylcellulose (EC) as shell material and calcium oxide (CaO) as core material. X-ray computed tomography (XCT) is used to trace and contrast the corrosion profiles of the concrete reinforcement bar with and without the microcapsule. The results show that the OH&minus;-regulated microcapsule exhibits effective corrosion protection by delaying corrosion initiation and cracking. An SEM study revealed that the microcapsule could be broken as Cl&minus; invades the concrete. However, intelligent OH&minus; regulation was realized by releasing CaO

    Influence mechanisms of CaCO3/NaAlO2 ratios in carbonaluminate cementitious materials

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    This study investigated the carbonaluminate cementitious materials (i.e., sodium aluminate (NaAlO2)-activated limestone pastes) with gradient calcite (CaCO3)/NaAlO2 molar ratios ranging from 1:1 to 6:1 (samples M1 to M6). NaAlO2 dosage affected the reaction process, hydration product, and cementitious property of the formed pastes. The thermonatrite (Na2CO3·H2O) and AH3 phase as hydration products exist in all the samples. Microcrystalline AH3 phase (crystallite size is near 22 nm) held a superior cementitious property, which was evidenced by diffraction spots scattered on concentric rings in transmission electron microscopy (TEM) results. Other hydrates varied with the CaCO3/NaAlO2 ratio. In case of lower CaCO3/NaAlO2 ratio (i.e., M1), NaAlO2 was incompletely consumed. The residual NaAlO2 promoted the formation of cubic-shaped katoite (3CaO·Al2O3·6H2O). Such hydrate barely contributed to the cementitious property of the formed matrix. When the CaCO3/NaAlO2 ratio reached 1.5:1 (e.g., M1.5-M6), NaAlO2 was entirely consumed, and monocarboaluminate (Mc, 3CaO·Al2O3·CaCO3·11H2O) instead of katoite was preferentially generated. The amounts of total hydrates decreased with the increasing CaCO3/NaAlO2 ratio, leading to the degraded properties of formed matrix. Thus, the 28-day compressive strength of M1.5 was the highest among these samples, reaching 35.55 MPa
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