• Journal of Practical Agriculture & Fisheries Research
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• v.16 no.1
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• pp.55-66
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• 2014

This study has been conducted to investigate the treatment time and concentration of GA₃ solution dipping for labor saving in 'Campbell Early' grapevine. The rachis growth at harvest was reduced by GA₃ solution dipping before 5 days flowering, and increased significantly by GA₃ solution dipping treatment at full bloom and after 5 days full bloom. GA₃ 5, 10, 20 mg·L^-1 dipping treatment before 5 days flowering and GA₃ 20 mg·L^-1 treatment of full bloom and after 5 days full bloom showed a rachis twist phytotoxicity symptom. The optimum GA₃ concentrations for rachis growth promotion without phytotoxicity were 5 mg·L^-1 and 10 mg·L^-1. The degree of compact berry, bloom, skin color, SSC and acidity at harvest by GA₃ solution dipping treatment time between concentration were not different from those of control. But the fruit berry weight was decreased by before 5 days flowering treatment when compared with control. There were no differences in full bloom and after 5 days full bloom treatment. The occurrence percent of berry cracking at before 5 days flowering and after 5 days full bloom treatment were significantly increased by GA₃ treatment. The bitter rot occurrence of berry at harvest was not affected by GA₃ treatment. Total rachis length of fruit cluster was increased by full bloom and 5 days after full bloom treatment. The length of rachis increased without reference to them position at full bloom and 5 days after bloom treatment. Accordingly, GA₃ 5 mg·L^-1 solution dipping treatment at full bloom and 5 days after full bloom were can be effectively for rachis growth promotion.

• Progress in Medical Physics
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• v.26 no.3
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• pp.160-167
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• 2015

Radiation exposure from medical diagnostic imaging procedures to patients is one of the most significant interests in diagnostic x-ray system. A miniature x-ray intraoral tube was developed for the first time in the world which can be inserted into the mouth for imaging. Dose evaluation should be carried out in order to utilize such an imaging device for clinical use. In this study, dose evaluation of the new x-ray unit was performed by 1) using a custom made in vivo Pig phantom, 2) determining exposure condition for the clinical use, and 3) measuring patient dose of the new system. On the basis of DRLs (Diagnostic Reference Level) recommended by KDFA (Korea Food & Drug Administration), the ESD (Entrance Skin Dose) and DAP (Dose Area Product) measurements for the new x-ray imaging device were designed and measured. The maximum voltage and current of the x-ray tubes used in this study were 55 kVp, and 300 mA. The active area of the detector was $72{\times}72mm$ with pixel size of $48{\mu}m$. To obtain the operating condition of the new system, pig jaw phantom images showing major tooth-associated tissues, such as clown, pulp cavity were acquired at 1 frame/sec. Changing the beam currents 20 to $80{\mu}A$, x-ray images of 50 frames were obtained for one beam current with optimum x-ray exposure setting. Pig jaw phantom images were acquired from two commercial x-ray imaging units and compared to the new x-ray device: CS 2100, Carestream Dental LLC and EXARO, HIOSSEN, Inc. Their exposure conditions were 60 kV, 7 mA, and 60 kV, 2 mA, respectively. Comparing the new x-ray device and conventional x-ray imaging units, images of the new x-ray device around teeth and their neighboring tissues turn out to be better in spite of its small x-ray field size. ESD of the new x-ray device was measured 1.369 mGy on the beam condition for the best image quality, 0.051 mAs, which is much less than DRLs recommended by IAEA (International Atomic Energy Agency) and KDFA, both. Its dose distribution in the x-ray field size was observed to be uniform with standard deviation of 5~10 %. DAP of the new x-ray device was $82.4mGy*cm^2$ less than DRL established by KDFA even though its x-ray field size was small. This study shows that the new x-ray imaging device offers better in image quality and lower radiation dose compared to the conventional intraoral units. In additions, methods and know-how for studies in x-ray features could be accumulated from this work.