COMPARATIVE STUDY ON PERFORMANCE OF VARIOUS ENVIRONMENTAL RADIATION MONITORS

After the Fukushima Daiichi Nuclear Power Plant accident, the radiation dose for first responders was not evaluated accurately due to lack of the monitoring data. It has been important to evaluate a radiation dose for workers in emergency response at a nuclear accident. In this study, a new device which can evaluate both of external and internal exposure doses was developed and the performance of various environmental radiation monitors including commercially available monitors were tested and compared from the viewpoint of an environmental monitoring at emergency situation. Background counts of the monitors and the ambient dose equivalent rate were measured in Fukushima Prefecture. The detection limit for beta particles was evaluated by the method of ISO11929. The sensitivity for gamma-rays of the dust monitor using a ZnS(Ag) and a plastic scintillator was high, but that of the external exposure monitor using a silicon photodiode with CsI(Tl) crystal was relatively low. The detection limit ranged 190-280 Bq m-3 at 100 μSv h-1, exceeding the detection limit of 100 Bq m-3 in the minimum requirement by the National Regulation Authority in Japan. Use of the shielding with lead is necessary to achieve the minimum requirement. These results indicate that the dust monitor using a ZnS(Ag) scintillator and a plastic scintillator is suitable for the external exposure monitor and the developed internal exposure monitor is for the internal exposure monitor at emergency situation among the evaluated monitors. In the future study, the counting efficiency, the relative uncertainty and the performance of the detection for alpha particles will be evaluated, and it will be considered which type of a monitor is suitable after taking the portability into account.

Correction: Myeloproliferative leukemia protein activation directly induces fibrocyte differentiation to cause myelofibrosis

Owing to the insufficient specificity of the anti-myeloproliferative leukemia protein (MPL) antibody in the original version of this Article, Figure 6 and parts of Figures 2a, 4e, and 5a do not represent the correct information. The corrected version of Figure 6 is in this correction and those of Figures 2a, 4e, and 5a are shown in the supplemental information.

Relationship between bronchial hyperresponsiveness and development of asthma in wheezy infants

STUDY OBJECTIVES

To evaluate the relationship between bronchial hyperresponsiveness (BHR) in infants with wheezing and the subsequent development of asthma.

INTERVENTION

Bronchial reactivity to inhaled methacholine (BRm) during the infantile period was studied using the transcutaneous partial pressure of oxygen (tcPO(2)) method. Children were followed long-term for the development of asthma.

PATIENTS

Fourteen children with bronchiolitis (mean age, 0.7 years) and 48 with wheezy bronchitis (mean age, 2.3 years) were enrolled. For comparison, 40 children with asthma (mean age, 4.6 years) and 27 healthy control subjects without chronic respiratory disease (mean age, 2.7 years) were studied.

MEASUREMENTS

Consecutive doses of methacholine were doubled until a 10% decrease in tcPO(2) from baseline was reached. The cumulative dose of methacholine (Dmin) at the inflection point of tcPO(2) (Dmin-PO(2)) was recorded.

RESULTS

During > 10 years of follow-up, seven patients with bronchiolitis developed asthma and all patients in the higher BRm set developed asthma, compared with none in the lower BRm set. In the wheezy bronchitis group, Dmin-PO(2) values in the 32 patients who developed asthma were lower than those in patients who had not developed asthma (p < 0.001).

CONCLUSIONS

We concluded that there is a tendency for infants with a clinical diagnosis of bronchiolitis or wheezy bronchitis and who show BHR in the infantile period to develop asthma. The presence of increased BHR after infantile respiratory diseases associated with wheezing may be a prelude to the development of childhood asthma.

[A study of the path diagram of the relationship between life style, mental health and psychosocial factors of nurses working at hospitals in Japan]

We conducted a study of 1,143 nurses working at hospitals in the southern part of Ibaraki prefecture in Japan to clarify the path diagram of the relationship between life style, mental health and psychosocial factors. General health questionnaire, life practice index, social support, number of night shifts and perceived health-status were used in this study. The data were analyzed using multivariate analysis and path analysis. The results are as follows: 1) The path analysis showed that General health questionnaire was directly affected by perceived health-status and social support. 2) General health questionnaire was directly and indirectly affected by Life practice index and social support. 3) Social support and number of night shifts were indirectly affected the General health questionnaire through the perceived health-status.