Purpose: To compare flat-panel detector (FPD) radiography and film-screen (FS) radiography in detectability of faint shadows documented as ground-glass attenuation (GGA) areas in images of computed tomography (CT).
Materials And Methods: Study population was comprised of 50 patients who underwent FS and another 50 patients who underwent FPD. Standard of reference (SOR) was determined on the basis of area of GGA in all cross-sections of CT, in terms of GGA extent and presence or absence of GGA in each trisected lung fields (GGA distribution). Eight radiologists assessed the GGA extent with the 5-grade scale and the GGA distribution. Inter-observer variances of the GGA extents and distributions, degree of divergences and correspondence in the GGA extent and distributions with SOR, were compared between the FS and FPD by the jackknife method and Fisher's exact test.
Results: Inter-observer variance in the GGA extent and distribution were slightly larger in the FS than in the FPD. The GGA extent scale corresponded with SOR in the FS statistically significantly better (p=0.001), as the correct ratio was 0.428 in the FS and 0.310 in the FPD. Divergence in the GGA extent scale with SOR was smaller in the FS, as average kappa pseudo-value of Kendall's rank correlation coefficient was 0.474 in the FS and 0.433 in the FPD.
Conclusion: These results indicate that some lesions of GGA documented in CT may not be reflected and are difficult to be detected in chest X-ray radiographs with the FPD.
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http://dx.doi.org/10.1016/j.ejrad.2009.04.057 | DOI Listing |
Chem Mater
November 2024
Department of Materials, Oxford University, Oxford OX1 3PH, U.K.
iScience
September 2024
Tumour Cell Biology Laboratory, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
Interactions between cells in the tumor microenvironment (TME) shape cancer progression and patient prognosis. To gain insights into how the TME influences cancer outcomes, we derive gene expression signatures indicative of signaling between stromal fibroblasts and cancer cells, and demonstrate their prognostic significance in multiple and independent squamous cell carcinoma cohorts. By leveraging information within the signatures, we discover that the HB-EGF/EGFR/MAPK axis represents a hub of tumor-stroma crosstalk, promoting the expression of CSF2 and LIF and favoring the recruitment of macrophages.
View Article and Find Full Text PDFJ Mol Model
July 2024
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China.
Context: The key factor in designing heat-resistant energetic materials is their thermal sensitivity. Further research and prediction of thermal sensitivity remains a great challenge for us. This study is based on first-principles calculations and establishes a theoretical model, which comprehensively considers band gap, density of states, and Young's modulus to obtain a empirical parameter Ψ.
View Article and Find Full Text PDFJ Chem Theory Comput
May 2024
Science Institute of the University of Iceland, Reykjavík 107, Iceland.
The performance of time-independent, orbital-optimized calculations of excited states is assessed with respect to charge transfer excitations in organic molecules in comparison to the linear-response time-dependent density functional theory (TD-DFT) approach. A direct optimization method to converge on saddle points of the electronic energy surface is used to carry out calculations with the local density approximation (LDA) and the generalized gradient approximation (GGA) functionals PBE and BLYP for a set of 27 excitations in 15 molecules. The time-independent approach is fully variational and provides a relaxed excited state electron density from which the extent of charge transfer is quantified.
View Article and Find Full Text PDFJ Mol Model
March 2024
School of Architecture and Civil Engineering, Shenyang University of Technology, Shenyang, 110870, China.
Context: This paper systematically analyzes the phonon dispersion curves of single-layer ZrS, ZrSe, and ZrS/ZrSe heterostructures under different strains. The phonon spectra and thermal parameters of the three structures were obtained based on the density functional perturbation theory method. The upper limits of strain that different monolayers and heterojunctions can withstand were studied.
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