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Knowledge of the three-dimensional distribution of minerals in a rock sample is of fundamental importance to deciphering a sample's properties and history. Attenuation-contrast X-ray computed tomography (X-ray CT) is widely used in the geosciences to determine the three-dimensional distributions of minerals or pores, or both. Photon counting CT (PC-CT) uses a novel energy-resolved X-ray detector that allows X-rays with a continuous energy spectrum to be detected separately within arbitrary energy ranges. Here we report the first results of applying laboratory-build PC-CT combined with multi-pixel photon counter (MPPC) to common minerals such as quartz and calcite. In the low-energy range, PC-CT produced higher contrast images than single-energy X-ray CT. Minerals were successfully identified from the relationships between the mean CT values for each energy window and the mean difference between pairs of energy windows. These results suggest that PC-CT can produce high-contrast images of minerals and may be able to distinguish mineral phases with different attenuation curves, even when their CT values are similar. We obtained CT images of minerals in a natural sedimentary rock sample, composed mainly of quartz and carbonate. Although the spatial resolution of the detector in this study was insufficient for the sample, the main carbonate veins were clearly visible as high carbonate-content areas in the PC-CT images. Given some prior knowledge of mineral phases from other methods, it may be possible to use PC-CT imaging to obtain further information about their chemical compositions. [ABSTRACT FROM AUTHOR]

Fine atmospheric particles, such as PM2.5, are strongly related to the onset and exacerbation of inflammatory responses leading to the development of respiratory and cardiovascular diseases. PM2.5 is a complex mixture of tiny particles with different properties (i.e., size, morphology, and chemical components). Moreover, the mechanism by which PM2.5 induces inflammatory responses has not been fully elucidated. Therefore, it is necessary to determine the composition of PM2.5 to identify the main factors causing PM2.5-associated inflammation and diseases. In the present study, we investigated PM2.5 from two sites (Fukue, a remote monitoring site, and Kawasaki, an urban monitoring site) with greatly different environments and PM2.5 compositions. The results of ICP-MS and EDX-SEM indicated that PM2.5 from Kawasaki contained more metals and significantly induced the expression of the pro-inflammatory cytokine gene IL-8 compared to the PM2.5 from Fukue. We also verified the increased secretion of IL-8 protein from exposure to PM2.5 from Kawasaki. We further investigated their effects on inflammatory response and cytotoxicity using metal nanoparticles (Cu, Zn, and Ni) and ions and found that the Cu nanoparticles caused a dose-dependent increase in IL-8 expression together with significant cell death. We also found that Cu nanoparticles enhanced the secretion of IL-8 protein. These results suggest that Cu in PM2.5 is involved in lung inflammation. [ABSTRACT FROM AUTHOR]

Objectives: To develop a prediction tool based on physical findings and environmental conditions without utilizing color Doppler ultrasonography to guide non‐urologists and patients' families in determining the testicular torsion possibility among patients with acute scrotal pain. Methods: Overall, 110 consecutive patients aged ≤30 years with acute scrotal pain at Saitama Medical Center between 2012 and 2014 were retrospectively evaluated. Physical examination results, including scrotal inspection, palpation and gait observation, and environmental conditions at pain onset (time range and ambient temperature) were collected. Multivariate analysis identified significant and independent risk factors for testicular torsion, and a nomogram predicting testicular torsion was constructed. The model underwent prospective validation in an independent set of 123 consecutive patients admitted with acute scrotal pain to our institution between 2015 and 2017. Results: Testicular torsion diagnosis rates were 27% (30/110) and 26% (32/123) in the training and validation cohorts, respectively. Logistic regression analysis showed four risk factors for developing testicular torsion: abnormal testicular position, walking difficulty, midnight to early morning onset and ambient temperature <15°C at pain onset. The constructed nomogram showed that the areas under the receiver operating characteristic curves were 0.92 and 0.84 for the training and validation cohorts, respectively. The calibration plot showed an acceptable fitness between the predicted probability and the observed rate of testicular torsion. Conclusions: A novel nomogram was developed solely based on physical findings and environmental conditions to predict testicular torsion in Japanese patients with acute scrotal pain. [ABSTRACT FROM AUTHOR]