For the determination of absorbed dose to water from a linear accelerator photon beams, it needs a exposure calibration factor Nx or air kerma calibration factor Nk of air ionization chamber. We used the exposure calibration factor Nx to find the absorbed dose calibration factors of water in a reference source through the TG-21 and TRS-277 protocol. TG-21 used for determine the absorbed dose in accuracy, but it required complex calculations including the chamber dependent factors. The authors obtained the absorbed dose calibration factor NdwCo-60 for reduce the complex calculations with unknown Ndw only with Nx or Nk calibration factor in a TM31010 (S/N 1055, 1057) ionization chambers. The results showed the uncertainty of calculated Ndw of IC-15 which was known the Nx and Ndw is within -0.6% in TG-21, but 1.0% in TRS-277. and TM31010 was compared the Ndw of SSDL to that of PSDL as shown the 0.4%, -2.8% uncertainty, respectively. The authors experimented with good agreement the calculated Ndw is reliable for cross check the discrepancy of the calibration factor with unknown that of TM31010 and IC-15 chamber.
Air Ionization ; Calibration ; Particle Accelerators ; Uncertainty ; Water

This study is to keep the accuracy and stability of the output dose evaluations for linear accelerator photon beams by using the air ionization chambers (TM31010, 0.125 cc, PTW) through the Task Group 51 protocol. The absorbed dose to water calibration factor NdwCo-60 was delivered from the air kerma calibration factor Nk which was provided from manufacture through SSDL calibration for determination of output factor. The ionization chamber of TM31010 series was reviewed the calibration factor and other parameters for reduce the uncertainty within +/-2% discrepancy and we found the supplied NdwCo-60 which was derived from Nk has shown a -2.8% uncertainty compare to that of PSDL. The authors provided the program to perform the output dosimetry with TG-51 protocol as it is composed same screen of TG-51 worksheets. The evaluated dose by determination of output factor delivered to postal TLD block for comparison the output dose to that of MDACC (RPC) in postal monitoring program. The results have shown the 1.001+/-0.013 for 6 MV and 0.997+/-0.012 discrepancy for 15 MV X rays for 5 years followed. This study shows the evaluated outputs for linear accelerate photon beams are very close to that of international output monitor with small discrepancy of +/-1.3% with high reliability and showing the gradually stability after 2010.
Air Ionization ; Calibration ; Organothiophosphorus Compounds ; Particle Accelerators ; Phenylpropionates ; Uncertainty ; Water

OBJECTIVETo investigate the short and long term efficacy of a commercial air ionizer in killing Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae) mites.

METHODSThe effect of a commercial ionizer on D. pteronyssinus and D. farinae was evaluated in the laboratory, using a specially designed test. Mortality was assessed after 6, 16 and 24 hours for direct exposure and after 24, 36, 48, 60 and 72 hours for exposure in simulated mattress. New batches of mites were used for each exposure time.

RESULTSLT50 for direct exposure of ionizer was 10 hours for D. pteronyssinus and 18 hours for D. farinae. The LT50 for exposure in simulated mattress was 132 hours or 5.5 days for D. pteronyssinus and 72 hours or 3 days for D. farinae. LT95 for direct exposure of ionizer was 36 hours for D. pteronyssinus and D. farinae. Meanwhile, the LT95 for exposure in simulated mattress was 956 hours or 39.8 days for D. pteronyssinus and 403 hours or 16.8 days for D. farinae.

CONCLUSIONSThis study demonstrates the increasing mite mortalities with increasing exposure time of a commercial ionizer and suggests that negative ions produced by an ionizer kill dust mites and can be used to reduce natural mite populations on exposed surfaces such as floors, clothes, curtains, etc. However, there is reduced efficacy on mites inside stuffed materials as in mattresses and furniture.

Air Ionization ; Animals ; Dermatophagoides farinae ; drug effects ; Dermatophagoides pteronyssinus ; drug effects ; Pest Control ; methods

In treatment of depression, non-pharmacological treatment is as important as pharmacological treatment. However, in clinical practice in Korea, non-pharmacological treatment is not provided sufficiently and patients are not satisfied with psychiatric interviews. Accordingly, patients ask for more information from clinicians. Clinicians should be aware of the characteristics of depression in Korean patients, because the manifestations of symptoms are influenced by cultural factors. In particular, depressed patients complain about somatic symptoms more frequently than they complain about depressed mood itself. In order to establish a therapeutic relationship with depressed patients, clinicians should be aware of these characteristics of depressed patients and clinicians should also address the needs of their patients. The author introduces evidence-based self-care methods for Korean patients with depression. St. John's wort, acupuncture, air ionization, light therapy, massage bibliotherapy, exercise, meditation, relaxation, and yoga can be helpful for overcoming depression. Among them, the Clinical Research Center for Depression, an organization supported by the Ministry of Health and Welfare, has recommended several non-pharmacological treatments for depression. First of all, exercise, such as walking more than 30 min. everyday, is strongly recommended. Other recommendations include bibliotherapy, interpersonal psychotherapy, cognitive behavioral therapy, and short-term psychodynamic supportive psychotherapy. For the nationwide management of depression, social bias against the treatment of depression should be reduced and non-pharmacological treatment for depression should be encouraged.
Acupuncture ; Air Ionization ; Bias (Epidemiology) ; Bibliotherapy ; Cognitive Therapy ; Depression ; Humans ; Hypericum ; Korea ; Massage ; Meditation ; Phototherapy ; Psychotherapy ; Relaxation ; Self Care ; Walking ; Yoga