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Simple, rapid and sensitive analysis of drug-derived pollutants is critically valuable for environmental monitoring. Here, taking acetaminophen, hydroquinone and catechol as a study example, a sensor based on an ITO/APTES/r-GO@Au electrode was developed for separate and simultaneous determination of phenolic pollutants. ITO electrodes that are modified with 3-aminopropyltriethoxysilane (APTES), graphene (GO) and Au nanoparticles (Au NPs) can significantly enhance the electronic transport of phenolic pollutants at the electrode surface. The redox mechanisms of phenolic pollutants include the electron transfer with the enhancement of r-GO@Au. The modified ITO electrode exhibits excellent electrical properties to phenolic pollutants and a good linear relationship between ECL intensity and the concentration of phenolic pollutants, with a limit of detection of 0.82, 1.41 and 1.95 μM, respectively. The separate and simultaneous determination of AP, CC and HQ is feasible with the ITO/APTES/r-GO@Au electrode. The sensor shows great promise as a low-lost, sensitive, and rapid method for simultaneous determination of drug-derived pollutants.

This paper studies the impact of global value chains (GVCs) participation on carbon emissions embodied in exports (EEE) of China during 2005-2016, and analyses firm heterogeneity from the perspective of firm ownership and trade patterns; Then, industries are classified based on factor intensity and technology level, and the industrial heterogeneity of different firms is analyzed; Finally, through counterfactual analysis, this paper evaluates EEE under four anti-globalization scenarios. The empirical study shows that with the increase of GVCs position, EEE first increases and then decreases, showing an inverted U-shaped distribution. From the perspective of firm ownership, the relationship between GVCs position of domestic firms and EEE is inverted U-shaped distribution, while GVCs position of multinational enterprises (MNEs) is positively correlated with EEE. The relationship of capital-intensive and technology-intensive domestic firms, high-tech and medium-tech manufacturing domestic firms are also inverted U-shaped distribution. The positive correlation of MNEs is reflected in the low-tech manufacturing industries. From the perspective of trade patterns, with the increase of GVCs position, EEE of processing trade firms presents an inverted U-shaped distribution, while it is not significant for general trade firms. The inverted U-shaped relationship between GVCs position in capital-intensive industries and EEE are confirmed in all firms. Under anti-globalization scenarios of 50% backflow, EEE would increase. Under scenarios of 100% backflow, EEE would reduce. The results above provide useful references to achieve carbon emission reduction targets.

Most Pseudoxanthomonas species described have been derived from water, plants, or contaminated soils. Here, a strain Pseudoxanthomonas sp. X-1 isolated from bromoxynil octanoate (BO)-contaminated soil is presented. Strain X-1 could degrade BO and produce bromoxynil. The optimal conditions for degradation of BO by strain X-1 were an initial BO concentration of 0.1 mM, 30 °C, pH 7, and Mn

Data management is a critical challenge required to improve the rigor and reproducibility of large projects. Adhering to Findable, Accessible, Interoperable, and Reusable (FAIR) standards provides a baseline for meeting these requirements. Although many existing repositories handle data in a FAIR-compliant manner, there are limited tools in the public domain to handle the metadata burden required to connect data from multi-omic projects that span multiple institutions and are deposited in diverse repositories. One promising approach is the SEEK platform, which allows for diverse metadata and provides an established repository. SEEK is challenged by the assumption of single deposition events where a sample is immutable once entered in the database. This is structured for published data but presents a limitation for ongoing studies where multiple sequential events may occur in a single sample at different sites. To address this issue, we have created a modified wrapper around the SEEK platform that allows for active data management by establishing more discrete sample types that are mutable to permit the expansion of the types of metadata, allowing researchers to track additional information. The use of discrete nodes also converts assays from nodes to edges, creating a network model of the study and more accurately representing the experimental process. With these changes to SEEK, users are able to collect and organize the information that researchers need to improve reusability and reproducibility as well as make data and metadata available to the scientific community through public repositories.

NF-κB is an evolutionarily conserved eukaryotic transcription factor that plays a role in many important developmental and immune-related processes by activating target gene expression. The goal of these experiments was to define the sequences required for a sea anemone NF-κB's intrinsic transactivation activity by using mutant proteins with serial deletions of the N- and C-terminal sequences. Deletion mutants were constructed that were missing the C-terminal 15, 32 or 47 amino acids (aa) or the N-terminal 17, 27 or 47 aa of the 440 aa NF-κB protein from the starlet sea anemone, Nematostella vectensis (Nv), a simple model organism in the phylum Cnidaria. These Nv-NF-κB mutants were expressed as GAL4 fusion proteins in yeast, and their transactivation activities were assessed by LacZ reporter gene assays. The deletion of 47 aa from either the N terminus or the C terminus of NF-κB completely inactivates the transactivation function of Nv-NF-κB. In addition, we identified proline-258 in the center ...

The analytical mobility method for dynamically loaded journal bearings was presented, with the intent to include it in a general computational program, such as the dynamic analysis program, that has been developed for the dynamic analysis of general mechanical systems. An illustrative example and numerical results were presented, with the efficiency of the method being discussed in the process of their presentation.

Multiwave frequency experiments were used to determine the critical gel behavior of the crystallizing melt of poly(phenylene sulfide) (PPS), which allowed for the simultaneous measurement of the viscoelastic properties at different oscillation frequencies. Therefore it was possible to determine the apparent critical gel point because of the shorter measuring time. The resulting critical gel time was related to the crystallization kinetics during the early stages. The isothermal crystallization kinetic of PPS was calculated by rheometer and hot stage-polarized light microscopy (PLM) experiments. The Avrami exponent n from PLM and rheological techniques was 2.9 and 2.7, therefore the two methods were around 3. The half crystallization time was 2025s for optical microscopy and 2112s for the rheological techniques, and were in good agreement with each other.

The phase equilibria and thermodynamic properties of the Ni–Mo system were analyzed by combining a first-principles approach and calculation of phase diagram (CALPHAD) technique. The first-principles calculation results indicate that Ni 2Mo and Ni8Mo are stable in addition to Ni3Mo and Ni4Mo, and-NiMo is not stable at 0 K, both in contradiction to the existing phase relationships in the Ni–Mo system. The enthalpies of the mixing of the bcc and fcc solid solution phases were also predicted by first-principles calculations using the special quasirandom structures. In the present work, the non-stoichiometric -NiMo and Ni3Mo phases were modeled using three- and two-sublattice models, respectively. The Ni2Mo, Ni4Mo and Ni8Mo phases were treated as stoichiometric compounds. Based on the first-principles data from the present work and experimental data in the literature, the Gibbs energy functions of individual phases were evaluated, and a new Ni–Mo phase diagram was presented. © 2005 Elsevier B.V. All rights reserved.

Considering the effects of temperature and composition, a phenomenological description of lattice parameters in solid states was developed. The lattice parameter of the pure element is modeled under the assumption of a linear temperature dependence of thermal expansion, while the lattice parameters of substitutional solid-solution phases are treated similar to the Gibbs-energy modeling in the CALPHAD (CALculation of PHAse Diagram) approach. Using this model, the lattice parameters of the γ and γ′ phases in the Ni-Al system were analyzed and the model parameters were evaluated. The calculated lattice parameters and mismatches show good agreement with existing experimental data.

The coarsening kinetics of c 0 precipitates in binary Ni–Al alloy is studied using three-dimensional (3D) phase-field simulations. The bulk thermodynamic information and atomic diffusion mobilities are obtained from databases constructed using the CALPHAD approach, while the experimental values for the interfacial energy, elastic constants and lattice mismatch are directly employed in the phase-field model. Specifically, we predict the morphological evolution, average precipitate size, and size distribution as a function of time for a given temperature and composition. Comparison of the phase-field simulation results with experiments shows good quantitative agreement in both time and length scales. 2004 Published by Elsevier Ltd on behalf of Acta Materialia Inc.

To quantitatively simulate microstructural evolution in real systems, we investigated three different interface models: a sharpinterface model implemented by the software DICTRA and two diffuse-interface models which use either physical order parameters or artificial order parameters. A particular example is considered, the diffusion-controlled growth of a c 0 precipitate in a supersaturated c matrix in Ni–Al binary alloys. All three models use the thermodynamic and kinetic parameters from the same databases. The temporal evolution profiles of composition from different models are shown to agree with each other. The focus is on examining the advantages and disadvantages of each model as applied to microstructure evolution in alloys. 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

RNA-Seq Viewer is a web application that enables users to visualize genome-wide expression data from NCBI’s Sequence Read Archive (SRA) and Gene Expression Omnibus (GEO) databases. The application prototype was created by a small team during a three-day hackathon facilitated by NCBI at Brandeis University. The backend data pipeline was developed and deployed on a shared AWS EC2 instance. Source code is available at https://github.com/NCBI-Hackathons/rnaseqview.

We studied the morphological evolution during spinodal phase separation and subsequent coarsening in systems with a strong dependence of elastic constants on the composition. An efficient numerical method is developed for solving the two-dimensional inhomogeneous elastic equilibrium equations by using the conjugate gradient method. A simple model binary system with a symmetric miscibility gap is considered. It is shown that the early stages of spinodal phase separation in a solid solution with a 50-50% composition always result in an interconnected morphology, regardless of the degree of elastic inhomogeneity. For systems with strong elastic inhomogeneity, particle splitting and coalescence take place concurrently during coarsening. In the late stages, the morphology has the characteristics that the hard phase forms precipitates surrounded by the soft phase which forms the matrix, similar to that predicted previously by others using first-order approximations. An analysis of the coarsening kinetics shows that although the growth exponent decreases with the increase in the degree of elastic inhomogeneity, there is no freezing of the coarsening kinetics for all the cases that we studied, in contrast to that predicted previously by others. The effect of an externally applied strain on the two-phase morphology in the elastic regime is also discussed.

We developed a numerical method for computing the effective properties of a microstructure. The method is particularly efficient and accurate for microstructures with a diffuse-interface description similar to those generated from phase-field simulations. In particular, we considered the diffusive transport property of a microstructure by solving the steady-state diffusion equation using a Fourier–Chebyshev spectral method. Computed effective diffusivities agree very well with existing analytical solutions and computer simulations for a number of simple model systems. Combining with the phase-field model for simulating microstructure evolution, the proposed method can be applied for modeling the temporal evolution of effective properties. This is illustrated by considering grain growth and the corresponding effective transport property evolution as function of time.

A simple and eAective numerical method is proposed for simulating the temporal diAusive mass transport process through a microstructure with arbitrary complexity described by a phase-field approach. The mass diAusion through a given microstructure is modeled by a diAusion equation with a variable diAusion coeAcient, which is solved by an eAcient and accurate semi-implicit spectral method. It is shown that it is possible to extract the eAective diAusion coeAcient for any given microstructure from the temporal concentration profiles. The method is used to simulate the grain boundary diAusion in a single-phase polycrystalline grain structure and the heterogeneous diAusion in a twophase microstructure with diAerent diAusion coeAcient in each phase. Results are compared with existing analytical theories and computer simulations. ” 2001 Elsevier Science B.V. All rights reserved.

An efficient semi-implicit Fourier spectral method is implemented to solve the Cahn-Hilliard equation with a variable mobility. The method is orders of magnitude more efficient than the conventional forward Euler finite-difference method, thus allowing us to simulate large systems for longer times. We studied the coarsening kinetics of interconnected two-phase mixtures using a Cahn-Hilliard equation with its mobility depending on local compositions. In particular, we compared the kinetics of bulk-diffusion-dominated and interface-diffusion-dominated coarsening in two-phase systems. Results are compared with existing theories and previous computer simulations.

Purpose To prospectively evaluate the accuracy of high-resolution (HR)-MRI as a secondary examination in women with abnormal calcifications detected on mammography. Materials and Methods We used a 4.7-cm microscopy coil to acquire HR-MRI signal data. We examined 52 women with breast lesions preoperatively using HR-MRI and vacuum-assisted core needle biopsy. The lesions were suspicious of malignancy, classified as category 3–5 on mammography (Breast Imaging Reporting and Data System [BI-RADS]), and without a palpable mass. All visualized suspicious lesions were correlated with histological findings. We compared the HR-MRI and pathological findings and calculated the sensitivity, specificity, and accuracy. Results We compared the breast HR-MRI results with the gold standard of pathological results for studies of malignancy (DCIS and invasive cancer), and found a sensitivity of 88.5%, specificity of 92.3%, and accuracy of 90.4%. The positive predictive value (PPV) was 92%, and the negative predictive value (NPV) was 88.9%. When breast MRI was compared with pathological results for studies that diagnosed DCIS only, the results revealed a sensitivity of 88.6%, specificity of 88.2%, accuracy of 88.5%, PPV of 93.9%, and NPV of 78.9%. Conclusion HR-MRI using a microscopy coil is a useful, reliable, safe, and minimally invasive procedure that is a good choice for secondary assessment of abnormal calcification in the breast. J. Magn. Reson. Imaging 2007. © 2006 Wiley-Liss, Inc.

The main objective of this work is to develop a set of integrated computational tools that can be employed to design Ni-base superalloys. In particular, we developed reliable thermodynamic, kinetic and lattice parameter databases for the Ni-Al-Mo superalloys by combining first-principles calculations and CALPHAD (CALculation of PHAse Diagrams) technique. Microstructural evolution of J’ precipitate particles was predicted using a quantitative phase-field model that is linked to the thermodynamic, kinetic and lattice parameter databases. Computational results of J’ coarsening were compared with literature data on particle sizes measured during aging experiments in binary NiAl alloys. The integrated multiscale computational tools have the potential to considerably reduce the time and cost for new superalloy development.