Cobalt Institute

ABSTRACTSeveral cancer potency estimates have been proposed by regulatory agencies to characterize the dose response of cobalt and/or cobalt compounds. The objective of this research is to investigate whether these proposed cancer potency estimates for certain cobalt substances align with the available epidemiology literature. After review of the epidemiological literature, we identified a study appropriate for our analysis. We established whether our identified study was adequately powered to detect an elevated lung cancer risk. The power analysis assumed a Poisson distribution and used a one‐sided significance level of 0.05. Lung tumors in animals served as the basis for cancer potency estimates for several regulatory bodies. The study population from our identified study was used to calculate predicted excess lung cancer deaths using potency values reported by four regulatory organizations, which were then compared to observed lung cancer deaths. Monte Carlo methods were used to estimate sample size and cobalt exposure distribution of the highest exposure group. We determined that the our identified study has ≥ 98% statistical power to detect a 1.5‐fold or greater increase in lung cancer due to cobalt exposure in all but the lowest exposure group and all four exposure groups had 100% statistical power to detect a 2.0‐fold or greater increase in lung cancer due to cobalt exposure. Cobalt exposure at the estimated median of the highest exposure group resulted in hypothetical standardized mortality ratios (SMR) estimated from the regulatory potency values ranging from 3.54 to 8.61 compared to an observed SMR of 1.15 (95% CI: 0.92–1.43) in our identified study. On the basis of this analysis, the cancer potency estimates proposed by the included regulatory organizations are likely overestimations of excess lifetime human cancer risk after cobalt inhalation exposure.

X-ray diffraction is widely used to characterise the mineral component of calcified tissue. Broadening of the diffraction peaks yields valuable information on the size of coherently diffracting domains, sometimes loosely described as crystallite size or crystallinity. These domains are markedly anisotropic, hence a single number describing their size is misleading. We present a novel variation on a method for visualising crystallographic anisotropy in X-ray diffraction data. This provides an intuitively interpretable depiction of crystalline domain size and anisotropy. The new method involves creating a polar plot of calculated domain thickness for peaks in a diffractogram versus crystallographic direction. Points with the least error are emphasised. Anisotropic domain dimensions are calculated by refining an ellipsoidal model in a whole pattern fit. These dimensions are then used to overlay an ellipse on the peak broadening plot. This is illustrated by application of the method to calcifications in breast tissue with suspected cancer, which frequently contain whitlockite as well as nanocrystalline apatite. Like most biogenic apatite, this exhibits markedly anisotropic peak broadening. The nature of this anisotropy offers potentially useful information on normal function and pathology of calcified tissue and is a frequently neglected crystallographic feature of these materials.

移転後の県庁舎周辺地区の特性に関する研究 ー産業分類別従業者数に着目してー A Study of the Characteristics of the Area Surrounding the Relocated Prefectural Government Building -Focusing on the Number of Employees by Industry Category-山本英輝 * ・黒瀬武史 ** YAMAMOTO Eiki , KUROSE Takefumi Several prefectures have relocated their prefectural government buildings (PGB) due to aging and cramped conditions. This report provides an overview of the relocation process of PGB and classifies the locations of relocated offices into three categories: within the central city, near the central city, and in the suburbs. The study then clarified the characteristics of the area surrounding the relocated PGB. We found that industries directly related to the prefectural government and prefectural assembly, industries serving the entire prefecture, and industries serving the PGB tend to be concentrated in the areas surrounding PGB. In the cities with typical industrial clusters, there were plots of land available for related industries from the time the land for the PGB was acquired, and district plans and other measures were in place to encourage the formation of these centers.

In an attempt to protect the high-risk demographic and reduce burden on health care systems, concomitant administration of COVID-19 and influenza vaccines has been recommended by health bodies. The ComFluCOV trial indicates this is well tolerated with no reduction in immune response to either vaccine. A 48-year-old woman with right oropharyngeal squamous cell carcinoma underwent postradiotherapy FDG PET/CT, which demonstrated complete metabolic response. Incidental avid bilateral axillary lymphadenopathy of benign configuration was noted and concluded to be reactive in response to recent Pfizer-BioNTech booster and influenza vaccination. This is expected to be seen more frequently over the coming months.

Ductal carcinoma in situ (DCIS) is frequently associated with breast calcification. This study combines multiple analytical techniques to investigate the heterogeneity of these calcifications at the micrometre scale. X-ray diffraction, scanning electron microscopy and Raman and Fourier-transform infrared spectroscopy were used to determine the physicochemical and crystallographic properties of type II breast calcifications located in formalin fixed paraffin embedded DCIS breast tissue samples. Multiple calcium phosphate phases were identified across the calcifications, distributed in different patterns. Hydroxyapatite was the dominant mineral, with magnesium whitlockite found at the calcification edge. Amorphous calcium phosphate and octacalcium phosphate were also identified close to the calcification edge at the apparent mineral/matrix barrier. Crystallographic features of hydroxyapatite also varied across the calcifications, with higher crystallinity centrally, and highest carbonate substitution at the calcification edge. Protein was also differentially distributed across the calcification and the surrounding soft tissue, with collagen and β-pleated protein features present to differing extents. Combination of analytical techniques in this study was essential to understand the heterogeneity of breast calcifications and how this may link crystallographic and physicochemical properties of calcifications to the surrounding tissue microenvironment.

As mineral exploration seeks deeper targets and targets under cover, the need for low cost and low impact subsurface imaging is increasingly important. A recent addition to the toolbox of geophysical methods is ambient noise surface wave tomography (ANSWT) which produces an S-wave velocity image of the subsurface using naturally occurring seismic signals from waves, oceans, trains, etc. - no active controlled seismic sources required. In this presentation, we provide a brief introduction of the ANSWT method and review two recent projects: Marathon Phase III and Schumann Lake, both projects located in Ontario, Canada.