Multi-view convolutional recurrent neural networks for lung cancer nodule identification

Screening via low-dose Computer Tomography (CT) has been shown to reduce lung cancer mortality rates by at least 20%. However, the assessment of large numbers of CT scans by radiologists is cost intensive, and potentially produces varying and inconsistent results for differing radiologists (and also for temporally-separated assessments by the same radiologist). To overcome these challenges, computer aided diagnosis systems based on deep learning methods have proved an effective in automatic detection and classification of lung cancer. Latterly, interest has focused on the full utilization of the 3D information in CT scans using 3D-CNNs and related approaches. However, such approaches do not intrinsically correlate size and shape information between slices. In this work, an innovative approach to Multi-view Convolutional Recurrent Neural Networks (MV-CRecNet) is proposed that exploits shape, size and cross-slice variations while learning to identify lung cancer nodules from CT scans. The multiple-views that are passed to the model ensure better generalization and the learning of robust features. We evaluate the proposed MV-CRecNet model on the reference Lung Image Database Consortium and Image Database Resource Initiative and Early Lung Cancer Action Program datasets; six evaluation metrics are applied to eleven comparison models for testing. Results demonstrate that proposed methodology outperforms all of the models against all of the evaluation metrics

Electrical transport and optical studies of ferromagnetic Cobalt doped ZnO nanoparticles exhibiting a metal-insulator transition

The observed correlation of oxygen vacancies and room temperature ferromagnetic ordering in Co doped ZnO1-o nanoparticles reported earlier (Naeem et al Nanotechnology 17, 2675-2680) has been further explored by transport and optical measurements. In these particles room temperature ferromagnetic ordering had been observed to occur only after annealing in forming gas. In the current work the optical properties have been studied by diffuse reflection spectroscopy in the UV-Vis region and the band gap of the Co doped compositions has been found to decrease with Co addition. Reflections minima are observed at the energies characteristic of Co+2 d-d (tethrahedral symmetry) crystal field transitions, further establishing the presence of Co in substitutional sites. Electrical transport measurements on palletized samples of the nanoparticles show that the effect of a forming gas is to strongly decrease the resistivity with increasing Co concentration. For the air annealed and non-ferromagnetic samples the variation in the resistivity as a function of Co content are opposite to those observed in the particles prepared in forming gas. The ferromagnetic samples exhibit an apparent change from insulator to metal with increasing temperatures for T>380K and this change becomes more pronounced with increasing Co content. The magnetic and resistive behaviors are correlated by considering the model by Calderon et al [M. J. Calderon and S. D. Sarma, Annals of Physics 2007 (Accepted doi: 10.1016/j.aop.2007.01.010] where the ferromagnetism changes from being mediated by polarons in the low temperature insulating region to being mediated by the carriers released from the weakly bound states in the higher temperature metallic region.Comment: 7 pages, 6 figure

Gauged linear sigma model and pion-pion scattering

A simple gauged linear sigma model with several parameters to take the symmetry breaking and the mass differences between the vector meson and the axial vector meson into account is considered here as a possibly useful template for the role of a light scalar in QCD as well as for (at a different scale) an effective Higgs sector for some recently proposed walking technicolor models. An analytic procedure is first developed for relating the Lagrangian parameters to four well established (in the QCD application) experimental inputs. One simple equation distinguishes three different cases:1. QCD with axial vector particle heavier than vector particle, 2. possible technicolor model with vector particle heavier than the axial vector one, 3. the unphysical QCD case where both the KSRF and Weinberg relations hold. The model is applied to the s-wave pion-pion scattering in QCD. Both the near threshold region and (with an assumed unitarization) theglobal region up to about 800 MeV are considered. It is noted that there is a little tension between the choice of bare sigma mass parameter for describing these two regions. If a reasonable globa fit is made, there is some loss of precision in the near threshold region.Comment: 19 pages, 9 figure

Wet chemical synthesis and characterisation of Ba0.5Sr0.5Ce0.6Zr0.2Gd0.1Y0.1O3 − δ proton conductor

M. N. Khan would like to thank University of Brunei Darussalam for a Graduate Research Scholarship. L.C. Lim and P. Hing thank UBD, and Government of Brunei Darussalam (S&T 17) for a generous research grant under the UBD Energy programme.Ba0.5Sr0.5Ce0.6Zr0.2Gd0.1Y0.1O3 − δ (BSCZGY) proton conducting electrolyte material for intermediate temperature solid oxide fuel cells (IT-SOFCs) has been synthesized by a sol-gel modified Pechini process and its sinterability, thermal expansion, microstructure, ionic conductivity and chemical stability have been investigated. Ionic conductivity at 700 °C was measured to be ~ 8 × 10− 3 S cm− 1 in wet 5 vol.% H2/Ar atmospheres. Chemical stability test in pure CO2 up to 1200 °C shows that the material is highly stable; better than the stability of BaZr0.3Ce0.5Y0.1Yb0.1O3 − δ.PostprintPeer reviewe

Effect of Reducing Atmosphere on the Magnetism of Zn1-xCoxO Nanoparticles

We report the crystal structure and magnetic properties of Zn1-xCoxO nanoparticles synthesized by heating metal acetates in organic solvent. The nanoparticles were crystallized in wurtzite ZnO structure after annealing in air and in a forming gas (Ar95%+H5%). The X-ray diffraction and X-ray photoemission spectroscopy (XPS) data for different Co content show clear evidence for the Co+2 ions in tetrahedral symmetry, indicating the substitution of Co+2 in ZnO lattice. However samples with x=0.08 and higher cobalt content also indicate the presence of Co metal clusters. Only those samples annealed in the reducing atmosphere of the forming gas, and that showed the presence of oxygen vacancies, exhibited ferromagnetism at room temperature. The air annealed samples remained non-magnetic down to 77K. The essential ingredient in achieving room temperature ferromagnetism in these Zn1-xCoxO nanoparticles was found to be the presence of additional carriers generated by the presence of the oxygen vacancies.Comment: 11 pages, 6 figures, submitted to Nanotechnology IO

A Mutlimodal Approach to Measure the Levels Distraction of Pedestrians using Mobile Sensing

The emergence of smart phones has had a positive impact on society as the range of features and automation has allowed people to become more productive while they are on the move. On the contrary, the use of these devices has also become a distraction and hindrance, especially for pedestrians who use their phones whilst walking on the streets. This is reinforced by the fact that pedestrian injuries due to the use of mobile phones has now exceeded mobile phone related driver injuries. This paper describes an approach that measures the different levels of distraction encountered by pedestrians whilst they are walking. To distinguish between the distractions within the brain the proposed work analyses data collected from mobile sensors (accelerometers for movement, mobile EEG for electroencephalogram signals from the brain). The long-term motivation of the proposed work is to provide pedestrians with notifications as they approach potential hazards while they walk on the street conducting multiple tasks such as using a smart phone

Hepatocellular carcinoma (HCC) versus non-HCC: accuracy and reliability of Liver Imaging Reporting and Data System v2018

PurposeThe Liver Imaging Reporting and Data System (LI-RADS) was created to standardize the diagnostic criteria for hepatocellular carcinoma (HCC) and has undergone multiple revisions including a recent update in 2018 (v2018). The primary aim of this study was to determine the diagnostic performance and interrater reliability (IRR) of LI-RADS v2018 for distinguishing HCC from non-HCC primary hepatic malignancy in patients at-risk' for HCC. A secondary aim was to assess the impact of changes introduced in the v2018 diagnostic algorithm.MethodsThis retrospective study combined a 10-year experience of pathologically proven primary liver malignancies from two large liver transplant centers. Two blinded readers independently evaluated each lesion and assigned a LI-RADS diagnostic category, additionally scoring all relevant imaging features. Changes in category based on the reader-provided features and the new v2018 criteria were assessed by a study coordinator.ResultsThe final study cohort comprised 105 HCCs and 73 non-HCC primarily liver malignancies. LI-RADS had a high specificity for distinguishing HCC from non-HCC (89% and 90% for reader 1 and reader 2, respectively), and IRR was moderate to substantial for final LI-RADS category and most features. Revision of the LI-RADS v2018 diagnostic algorithm resulted in very few changes [5 (2.8%) and 3 (1.7%) for reader 1 and reader 2, respectively] in overall lesion classification.ConclusionLI-RADS diagnostic categories and features had moderate to substantial IRR and high specificity for distinguishing HCC from non-HCC primary liver malignancy. Revision of LI-RADS v2018 diagnostic algorithm resulted in reclassification of very few lesions

Expanding the Liver Imaging Reporting and Data System (LI-RADS) v2018 diagnostic population: performance and reliability of LI-RADS for distinguishing hepatocellular carcinoma (HCC) from non-HCC primary liver carcinoma in patients who do not meet strict LI-RADS high-risk criteria

Background: Hepatocellular carcinoma (HCC) can be diagnosed using imaging criteria in patients at high-risk for HCC, according to Liver Imaging Reporting and Data System (LI-RADS) guidelines. The aim of this study was to determine the diagnostic performance and inter-rater reliability (IRR) of LI-RADS v2018 for differentiating HCC from non-HCC primary liver carcinoma (PLC), in patients who are at increased risk for HCC but not included in the LI-RADS 'high-risk' population.Methods: This retrospective HIPAA-compliant study included a 10-year experience of pathologicallyproven PLC at two liver transplant centers, and included patients with non-cirrhotic hepatitis C infection, non-cirrhotic non-alcoholic fatty liver disease, and fibrosis. Two readers evaluated each lesion and assigned an overall LI-RADS diagnostic category, additionally scoring all major, LR-M, and ancillary features.Results: The final study cohort consisted of 27 HCCs and 104 non-HCC PLC in 131 patients. The specificity of a 'definite HCC' designation was 97% for reader 1 and 100% for reader 2. The IRR was fair for overall LI-RADS category and substantial for most major features.Conclusion: In a population at increased risk for HCC but not currently included in the LI-RADS 'high-risk' population, LI-RADS v2018 demonstrated very high specificity for distinguishing pathologicallyproven HCC from non-HCC PLC

Integrated transcriptomic and proteomic analysis of pathogenic mycobacteria and their esx-1 mutants reveal secretion-dependent regulation of ESX-1 substrates and WhiB6 as a transcriptional regulator

The mycobacterial type VII secretion system ESX-1 is responsible for the secretion of a number of proteins that play important roles during host infection. The regulation of the expression of secreted proteins is often essential to establish successful infection. Using transcriptome sequencing, we found that the abrogation of ESX-1 function in Mycobacterium marinum leads to a pronounced increase in gene expression levels of the espA operon during the infection of macrophages. In addition, the disruption of ESX-1-mediated protein secretion also leads to a specific down-regulation of the ESX-1 substrates, but not of the structural components of this system, during growth in culture medium. This effect is observed in both M. marinum and M. tuberculosis. We established that down-regulation of ESX-1 substrates is the result of a regulatory process that is influenced by the putative transcriptional regulator whib6, which is located adjacent to the esx-1 locus. In addition, the overexpression of the ESX-1-associated PE35/PPE68 protein pair resulted in a significantly increased secretion of the ESX-1 substrate EsxA, demonstrating a functional link between these proteins. Taken together, these data show that WhiB6 is required for the secretion-dependent regulation of ESX-1 substrates and that ESX-1 substrates are regulated independently from the structural components, both during infection and as a result of active secretion