A deep learning-based framework for automatic analysis of the nanoparticle morphology in SEM/TEM images.

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are important tools for characterizing nanomaterial morphology. Automatic analysis of the nanomaterial morphology in SEM/TEM images plays a crucial role in accelerating research on nanomaterials science. However, achieving a high-throughput automated online statistical analysis of the nanomaterial morphology in various complex SEM/TEM images is still a challenging task. In this paper, we propose a universal framework based on deep learning to perform a fast and accurate online statistical analysis of the nanoparticle morphology in complex SEM/TEM images. The proposed framework consists of three stages that are nanoparticle segmentation using a powerful light-weight deep learning network (NSNet), nanoparticle shape extraction, and statistical analysis. The experimental results show that NSNet in the proposed framework has achieved an accuracy of 86.2% and can process 11 SEM/TEM images per second on an embedded processor. Compared with other semantic segmentation models, NSNet is an optimal choice to ensure that the proposed framework still achieves accurate and fast segmentation even in SEM/TEM images with high background interference, extremely small nanoparticles and dense nanoparticles. Meanwhile, the equivalent diameter and Blaschke shape coefficient of the nanoparticle obtained by the proposed framework are 17.14 ± 5.9 and 0.18 ± 0.04, which are well consistent with those of manual statistical analysis. In short, the proposed framework has a promising future in driving the development of automatic and intelligent analysis technology for nanomaterial morphology.

Meta-analysis on the association between xeroderma pigmentosum Group A A23G polymorphism and esophageal cancer in a Chinese population.

AIM OF THE STUDY: Several studies have evaluated the correlation between xeroderma pigmentosum Group A (XPA) A23G polymorphism (rs 1800975) and esophageal cancer in Chinese people. However, the results are inconsistent. To assess the effects of XPA A23G variants on the risk for development of esophageal cancer in the Chinese population, a meta-analysis was performed. MATERIALS AND METHODS: Studies were identified using PubMed and Chinese databases through December 2015. The associations were assessed with pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: This meta-analysis identified seven studies including 1514 esophageal cancer cases and 2120 controls. In the overall analysis, no significant association between XPA A23G polymorphism and esophageal cancer was found in the Chinese population. In the subgroup analyses by geographic area(s) and source of controls, significant results were only found in studies with hospital-based controls (GG vs. AA: OR = 0.42, 95% CI = 0.28-0.62; GG vs. AA + AG: OR = 0.55, 95% CI = 0.39-0.78; GG + AG vs. AA: OR = 0.54, 95% CI = 0.40-0.72; G vs. A: OR = 0.61, 95% CI = 0.50-0.75). CONCLUSIONS: This meta-analysis suggested that XPA A23G gene polymorphism may be one low-penetrant risk factor for esophageal cancer in Chinese individuals.

Observational studies and a statistical early warning of surface ozone pollution in Tangshan, the largest heavy industry city of North China.

Continuous measurements of surface ozone (O3) and nitrogen oxides (NOX) at an urban site (39°37'N, 118°09'E) in Tangshan, the largest heavy industry city of North China during summertime from 2008 to 2011 are presented. The pollution of O3 was serious in the city. The daily maximum 1 h means (O3_1-hr max) reached 157 ± 55, 161 ± 54, 120 ± 50, and 178 ± 75 µg/m3 corresponding to an excess over the standard rates of 21%, 27%, 10%, and 40% in 2008-2011, respectively. The total oxidant level (OX = O3 + NO2) was high, with seasonal average concentrations up to 100 µg/m3 in summer. The level of OX at a given location was made up of NOX-independent and NOX-dependent contributions. The independent part can be considered as a regional contribution and was about 100 µg/m3 in Tangshan. Statistical early warning analysis revealed that the O3 levels would exceed the standard rate by 50% on the day following a day when the daily average ozone concentration (O3_mean) exceeded 87 µg/m3 and the daily maximum temperature (T_max) exceeded 29 °C. The exceed-standard rate would reach 80% when O3_mean and T_max exceeded 113 µg/m3 and 31 °C. Similarly, the exceed-standard rate would reach 100% when O3_mean and T_max exceeded 127 µg/m3 and 33 °C, respectively.

A novel evaluation method for building construction project based on integrated information entropy with reliability theory.

Selecting construction schemes of the building engineering project is a complex multiobjective optimization decision process, in which many indexes need to be selected to find the optimum scheme. Aiming at this problem, this paper selects cost, progress, quality, and safety as the four first-order evaluation indexes, uses the quantitative method for the cost index, uses integrated qualitative and quantitative methodologies for progress, quality, and safety indexes, and integrates engineering economics, reliability theories, and information entropy theory to present a new evaluation method for building construction project. Combined with a practical case, this paper also presents detailed computing processes and steps, including selecting all order indexes, establishing the index matrix, computing score values of all order indexes, computing the synthesis score, sorting all selected schemes, and making analysis and decision. Presented method can offer valuable references for risk computing of building construction projects.

Epidermal growth factor receptor-related DNA repair and radiation-resistance regulatory mechanisms: a mini-review.

Epidermal growth factor receptor (EGFR) overexpression is associated with resistance to chemotherapy and radiotherapy. The EGFR modulates DNA repair after radiation-induced damage through an association with the catalytic subunit of DNA protein kinase. DNA double-strand breaks (DSBs) are the most lethal type of DNA damage induced by ionizing radiation, and non-homologous end joining is the predominant pathway for repair of radiation-induced DSBs. Some cell signaling pathways that respond to normal growth factors are abnormally activated in human cancer. These pathways also invoke the cell survival mechanisms that lead to resistance to radiation. The molecular connection between the EGFR and its control over DNA repair capacity appears to be mediated by one or more signaling pathways downstream of this receptor. The purpose of this mini-review was not only to highlight the relation of the EGFR signal as a regulatory mechanism to DNA repair and radiation resistance, but also to provide clues to improving existing radiation resistance through novel therapies based on the above-mentioned mechanism.

[Application research of data assimilation in air pollution numerical prediction].

Based on an air pollution modeling system coupling with the non-hydrostatic fifth generation mesoscale meteorological model (MM5) and the regional modeling system for aerosols and deposition (REMSAD), the forecast results of NOx and SO2 in August and September 2002 in Nanjing were assimilated with the optimal interpolation method and the ensemble Kalman filter. The results show that the improvement rates of deviation mean value of NOx and SO2 after assimilated with the optimal interpolation method are 34.20% and 47.53%, and the improvement rates of root mean square errors are 31.95% and 42.04% respectively. It is also demonstrated that the improvement rates of deviation mean value of NOx and SO2 after assimilated with the ensemble Kalman filter with 30 ensemble members are 26.73% and 60.75%, and the improvement rates of root mean square errors are 25.20% and 55.16% respectively. So, the optimal interpolation method and the ensemble Kalman filter both can improve the quality of the initial state from the air pollution numerical prediction model. The comparative experiments on the assimilation performance with the optimal interpolation method and the ensemble Kalman filter with 61 ensemble members were performed, and the experiments demonstrate that the assimilation performance of the ensemble Kalman filter with 61 ensemble members were improved compared with 30 ensemble members, and with the increase of the ensemble members, the improvement to the initial state of NOx and SO2 with the ensemble Kalman filter will be better than the optimal interpolation method.