Monte Carlo estimation of radiation doses in red bone marrow and breast in common pediatric x-ray examinations

Radiation exposure was investigated for children undergoing various common radiographies in three dedicated pediatric hospitals in Greece. Kerma in air at the entrance of the beam (Ka,e) was measured with thermoluminescent dosimeters. Ka,e values ranged from 0.09 mGy to 5.52 mGy and were found to be greater in Hospital C, because of the increased high voltage and time-current product used by the radiation technologists. Equivalent doses in red bone marrow and breast were estimated with Monte Carlo simulation by PCXMC code. Values ranged from 2 microSv to 204 microSv for red bone marrow and from 0 to 817 muSv for breast. Variation in doses occurred due to field size, high voltage setting, and Ka,e.     

Working in the sky: a diary study on work engagement among flight attendants

This study aims to gain insight in the motivational process of the Job Demands-Resources (JD-R) model by examining whether daily fluctuations in colleague support (i.e., a typical job resource) predict day-levels of job performance through self-efficacy and work engagement. Forty-four flight attendants filled in a questionnaire and a diary booklet before and after consecutive flights to three intercontinental destinations. Results of multilevel analyses revealed that colleague support had unique positive effects on self-efficacy and work engagement. Self-efficacy did not mediate the relationship between support and engagement, but work engagement mediated the relationship between self-efficacy and (in-role and extra-role) performance. In addition, colleague support had an indirect effect on in-role performance through work engagement. These findings shed light on the motivational process as outlined in the JD-R model, and suggest that colleague support is an important job resource for flight attendants helping them reach their work-related goals.     

Elevated vWF Antigen Serum Levels Are Associated With Poor Prognosis,and Decreased Circulating ADAMTS-13 Antigen Levels Are Associated With Increased IgM Levels and Features of WM but not Increased vWF Levels in Patients With Symptomatic WM

Background

Waldenström's macroglobulinemia (WM) is a rare malignancy characterized by bone marrow infiltration by lymphoplasmacytic cells and the presence of a monoclonal IgM paraprotein. The interactions of lymphoplasmacytic cells with other cells in their microenvironment, including mast cells and endothelial cells, support their survival and proliferation and can induce resistance to therapy. von Willebrand factor (vWF) plays a key role in primary hemostasis but is also a marker of endothelial “stimulation.” High levels of vWF have been associated with an adverse prognosis in patients with symptomatic WM and might reflect the interactions between lymphoplasmacytic cells and other cells of their microenvironment.