• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.107-117
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• 2024

This study investigated temporal changes in forest physical variables and their effects on thermal comfort and physiological and psychological responses. Environmental factors (air temperature, mean radiant temperature, wind speed, and relative humidity), the predicted mean vote (PMV), and the predicted percentage of dissatisfied (PPD) visitors were continuously measured between 9:00 AM and 6:00 PM. We assessed the physiological and psychological responses (heart rate variability, heart rate, oral temperature, blood pressure, pulse rate, thermal sensation vote, comfort sensation vote, and subjective feelings) of 30 male university students (average age: 21.7±1.9 years), who closed their eyes and relaxed for 5 minutes every hour. Examination of correlations between environmental factors and physiological responses showed that ① the mean radiant temperature, wind speed, and relative humidity significantly changed with time; ② PMV and PPD also showed significant changes over time, and the thermal sensation vote corresponded with PMV; however, the comfort sensation vote did not correspond with PPD; ③ Among the physiological responses, parasympathetic nerve activity, sympathetic nerve activity, heart rate, and diastolic blood pressure significantly varied with time, with parasympathetic nerve activity having the lowest value and sympathetic nerve activity the highest at the highest air temperature (2:00-4:00 PM); and ④ Air temperature, mean radiant temperature, and wind speed showed a negative correlation with parasympathetic nerve activity and a positive correlation with sympathetic nerve activity. These findings indicate that the relaxation effects of the forest environment depend on what time of day people are exposed to it, and the changes occurring in forest environmental factors over time modulate these effects.

• Journal of Chest Surgery
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• v.41 no.5
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• pp.568-572
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• 2008

Background: Minimally invasive surgery is currently popular, but this has been applied very sparingly to cardiac surgery because of some limitations. Our study evaluated the safety and efficacy of atrial septal defect (ASD) closure through a video-assisted mini-thoracotomy. Material and Method: Fifteen patients were analyzed. Their mean age was $31{\pm}6$ years. The mean ASD size was $24{\pm}5mm$ and there were 3 cases of significant tricuspid regurgitation. The working window was made through the right 4th intercostal space via a $4{\sim}5cm$ inframammary skin incision, CPB was conducted with performing peripheral cannulation. After cardioplegic arrest, the ASDs were closed with a patch (n=11) or direct sutures (n=4), and the procedures were assisted by using a thoracoscope. There were 3 cases of tricuspid repair and 1 case of mitral valve repair. The mean CPB time and aortic occlusion time were $160{\pm}47\;and\;70{\pm}26 $minutes, respectively. Result: There was no mortality, but there were 3 minor complications (one pneumothorax, one wound dehiscence and one arrhythmia). The mean hospital stay was $5.9{\pm}1.8$ days. The mean follow-up duration was $10.7{\pm}6.4$ months. The follow-up echocardiogram noted no residual ASD or significant tricuspid regurgitation. Three patients suffered from pain or numbness. Conclusion: This study showed satisfactory clinical and cosmetic results. Although the operative time is still too long, more experience and specialized equipment would make this technique a good option for treating ASD.