• Journal of Chest Surgery
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• 제22권4호
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• pp.609-619
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• 1989

During aortic valve surgery, cardioplegic solution is delivered through direct cannulation of both coronary ostia. Since this approach may cause an intimal injury leading to acute dissection or late ostial stenosis, this study was undertaken to evaluate myocardial protective effect of retrograde perfusion of cardioplegia [RCSP <% RRAP] in 18 clinical cases, which were compared with antegrade perfusion of cardioplegia in 27 clinical cases. This study were investigated 1] cease and return of electromechanical activity after cardioplegia infusion 2] the myocardial temperature during operation 3] the aortic cross clamping time and total bypass time 4] frequency of DC shock for defibrillation 5] need for inotropic drugs after operation 6] electrocardiographic evidence of myocardial infarction or ventricular arrhythmia after operation 7] the enzymes activity during preoperative and postoperative period as an evaluation of myocardial ischemic injury and 8] operative mortality rate The combination of retrograde cardioplegia and topical cooling with ice slush yielded promptly hypothermia of myocardium and shorter aortic cross-clamping time compared with antegrade cardioplegia [P < 0.05]. The temperature of the interventricular septum was maintained below 20oC by continuous perfusion or intermittent perfusion of cold blood cardioplegia and other results were no statistically significant difference between the two methods [P >0.05]. This technique provides clear operative field and avoids some serious complications which are caused by coronary ostial cannulation. These results suggested that the retrograde perfusion of cardioplegia is a simple, safe, and effective means of myocardial protection during open heart surgery.

• 한국주거학회논문집
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• 제10권1호
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• pp.75-84
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• 1999

The purpose of this study is to identify the characteristics of the thermal environment, and to analyze the relationship between the thermal reactions and the skin temperatures in the lying position in the radiant floor heating system. The results are as follows: 1) The globe temperature was nearly equal to the operative temperature in the room. 2) The floor surface temperature and the globe temperature were 26.4$^{\circ}C$ and 23.6$^{\circ}C$, respectively when the whole body temperature was at neutral point. 3) The mean temperature of the six skin parts was 31.3$^{\circ}C$ (cold thermal environment); 34.1$^{\circ}C$ (neutral thermal environment); 35.1$^{\circ}C$ (hot thermal environment).

• 대한치과의사협회지
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• 제10권8호
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• pp.531-534
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• 1972

The author measured exothermic temperature of the 5 kinds of zinc phosphate cement and 3 kinds of copper phosphate cement during setting process. Cements were mixed on the glass slab with flexible steel spatula at room temperature (25.8℃) for one minute (spatulating speed was 100 strokes per minute) and placed in the incubator of which temperature was held at 37℃ and thermometer was inserted into the cement mass. The powder liquid ration was 3.0gm:1ml and 1.5gm:1ml. The results were as follows. 1) The heat generated after mixing these cements was under 47.22℃. 2) The range of thermal change of the zinc phosphate cements during setting process was wider than copper phosphate cements. 3) The exothermic temperature from the thin mix was higher than thick mix. 4) The exothermic temperature of the zinc phosphate cements was higher than copper phosphate cements.

• Restorative Dentistry and Endodontics
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• 제44권4호
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• pp.41.1-41.13
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• 2019

Objectives: This paper presents a systematic review and meta-analysis of the effect of preheating on the hardness of nanofilled, nanoceramic, nanohybrid, and microhybrid resin composites. Materials and Methods: An electronic search of papers on MEDLINE/PubMed, ScienceDirect, and EBSCOhost was performed. Only in vitro studies were included. Non-English studies, case reports, clinical trials, and review articles were excluded. A meta-analysis of the reviewed studies was conducted to quantify differences in the microhardness of the Z250 microhybrid resin composite using the Comprehensive Meta-Analysis software. Results: Only 13 studies met the inclusion criteria for this systematic review. The meta-analysis showed that there were significant differences between the non-preheated and preheated modes for both the top and bottom surfaces of the specimens (p < 0.05). The microhardness of the Z250 resin composite on the top surface in the preheated mode (78.1 ± 2.9) was higher than in the non-preheated mode (67.4 ± 4.0; p < 0.001). Moreover, the microhardness of the Z250 resin composite on the bottom surface in the preheated mode (71.8 ± 3.8) was higher than in the non-preheated mode (57.5 ± 5.7, p < 0.001). Conclusions: Although the results reported in the reviewed studies showed great variability, sufficient scientific evidence was found to support the hypothesis that preheating can improve the hardness of resin composites.

• Restorative Dentistry and Endodontics
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• 제45권4호
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• pp.44.1-44.9
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• 2020

Objectives: Phytic acid (IP6), a naturally occurring agent, has been previously reported as a potential alternative to ethylenediaminetetraacetic acid (EDTA). However, its effect on adhesion to sodium hypochlorite (NaOCl)-treated dentin and its interactions with NaOCl have not been previously reported. Thus, in this study, the effects of IP6 on resin adhesion to NaOCl-treated dentin and the failure mode were investigated and the interactions between the used agents were analyzed. Materials and Methods: Micro-tensile bond strength (µTBS) testing was performed until failure on dentin treated with either distilled water (control), 5% NaOCl, or 5% NaOCl followed with chelators: 17% EDTA for 1 minute or 1% IP6 for 30 seconds or 1 minute. The failed specimens were assessed under a scanning electron microscope. The reaction of NaOCl with EDTA or IP6 was analyzed in terms of temperature, pH, effervescence, and chlorine odor, and the effects of the resulting mixtures on the color of a stained paper were recorded. Results: The µTBS values of the control and NaOCl with chelator groups were not significantly different, but were all significantly higher than that of the group treated with NaOCl only. In the failure analysis, a distinctive feature was the presence of resin tags in samples conditioned with IP6 after treatment with NaOCl. The reaction of 1% IP6 with 5% NaOCl was less aggressive than the reaction of the latter with 17% EDTA. Conclusions: IP6 reversed the adverse effects of NaOCl on resin-dentin adhesion without the chlorine-depleting effect of EDTA.

• 대한치과의사협회지
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• 제11권1호
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• pp.37-40
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• 1973

The auther measured exothermic tempreature of the 5 kinds of direct resins during polymerization. Direct resins were mixed into the rubber cup(550-600㎣ in volume) with grass rod at room temperature (23.6℃) for 30 seconds and thermometer was placed approximately at the geometric center of the resin mass in the rubber cup. Polymer-monomer ratio was determined by instruction of the packages. The results were as follows. 1) The heat generated during polymerization was under 47.3℃. 2) The time at which the highest temperature is reached during polymerization was within 20.5 minutes. 3) Slow curing resins produced lower heat than quick curing resins and quick curing resins presented higher temperature than slow curing resins. 4) The highest temperature was sustained momentarily.

• 한국주거학회논문집
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• 제15권2호
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• pp.19-25
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• 2004

The aim of the research was to evaluate the characteristics of indoor thermal environment and thermal sensation in the traditional Ondol room. Indoor thermal factors including air temperature, operative temperature, floor surface temperature, relative humidity, PMV, OT were measured, and survey was carried out to understand subjective responses of resident's related to indoor thermal environment in Ondol room. The analysed houses are: the Chung hyo dang(the head house of Ryu family in Andong) and the Pyeung won jung(the traditional house in Yesan). The purpose of the survey was to know the relationship between resident's sensation and thermal environmental indicators such as air temperature, relative humidity, floor surface temperature, OT. The experimental results have pointed out how Ondol room may lead to comfortable and uniform indoor thermal environments.

• 기본간호학회지
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• 제20권2호
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• pp.108-117
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• 2013

Purpose: The purpose of this study was to identify the factors that affect body temperature in elderly operation patients using a warming method and to examine differences in post operative body temperature by characteristics of the patients. Methods: Data were collected from 200 patients, aged 65 years or more undergoing surgery with a warming method. The data were analyzed using descriptive statistics, t-test, ANOVA, Scheffe's test and multiple regression with the SPSS 18.0 Program. Results: The mean score for body temperature of elderly operation patients using a warming method after surgery was $36.1{\pm}0.6^{\circ}C$ including 74 patients with hypothermia and 126 patients with normal body temperature. The body temperature according to general characteristics differed by age and whether the surgery was emergency surgery or not. The body temperature according to surgery-related factors differed by anesthesia type, length of operation, anesthesia time, magnitude of surgical procedure, amount of fluid, transfusion requirements, and preoperative body temperature. Factors influencing body temperature were age, BMI, transfusion requirements and preoperative body temperature. Conclusion: The results indicate that age, BMI, transfusion requirements and preoperative body temperature significantly influenced on body temperature after surgery. Thus preoperative body temperature needs to be maintained through pre-warming as a nursing intervention.

• KIEAE Journal
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• 제12권4호
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• pp.97-104
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• 2012

A phase-change material is a substance with a high heat of fusion which, melting and freezing at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid. Therefore, PCMs are classified as latent heat storage (LHS) units. The purpose of this study is to analyze PCM wallboard design parameters using dynamic energy simulation. Among the factors of PCM, melting temperature, latent heat, phase change range, thermal conductivity are very important element to maximize thermal energy storage. In order to analyze these factors, EnergyPlus which is building energy simulation provided by department of energy from the U.S is used. heat balance algorithm of energy simulation is conduction finite difference and enthalpy-temperature function is used for analyzing latent heat of PCM. The results show that in the case of melting temperature, the thermal energy storage could be improved when the melting temperature is equal to indoor surface temperature. It seems that when the phase change range is wide, PCM can store heat at a wide temperature, but the performance of heat storage is languished.

• 기본간호학회지
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• 제7권1호
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• pp.86-96
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• 2000

The purpose of the study was to investigate the effects of Warming Therapy used with patients consistantly before and during surgery to on changes in their body temperatures. The data were collected from patients in a university hospital in Taegu between December 1, 1998 and May 31, 1999. The subjects were selected from patients who were hospitalized for total hip replacement surgery. Thirty participants were assigned to two groups : experimental(Warming Therapy) group and control group. Each group consisted of 15 patients. The research design was a repeated measurement design, using a nonequivalent control group. The Warming Therapy, using a forced-air warming blanket, that is a, 'Bair Hugger' was applied to subjects in the experimental group. The subjects in the group were treated with the 'Bair Hugger' to warm up the whole body for 40 minutes before surgery and upper body and face during the operation. The core temperature was measured using a tympanic thermometer. The body temperature of the patients was measured 13 times every 15 minutes during the surgery. After the operation the body temperature of the patients was measured 4 times every 15 minutes, from the time of arrivial in the recovery room to the time of leaving the recovery room. The SPSS Win 9.0 program was used for data analysis. Specific methods tested were done using ${\chi}^2-test$, t-test, repeated measures ANOVA. The findings of the study are as follows. 1. The first hypothesis, 'The level of tympanic temperature for the experimental group which received Warming Therapy will be higher than that of the control group during the operation', was supported (F=32.16, p=.000). 2. The second hypothesis, 'The level of tympanic temperature for the experimental group which received Warming Therapy will be higher than that of the control group after the operation', was supported.(F=33.36, p=.000) 3. During recovery, shivering was observed one patient in the experimental group and seven patients in the control group. In summary, the findings of the study suggest that the 'Warming Therapy' applied before and during the surgery was a very effective treatment for surgical patients in maintaining the core temperature during surgery