식단의 당부하량에 따른 20대 성인의 체중 감량 효과 연구 (Effects of a low glycemic load diet on body weight loss in overweight or obese young adults)
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- Journal of Nutrition and Health
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- 제53권5호
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- pp.464-475
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- 2020
본 연구에서는 한국인이 평소 섭취하는 일반식사와 유사한 수준의 당부하량을 가진 high GL 식사와 당부하량이 낮게 설계된 low GL 식사를 섭취한 후 체중, 체지방, 혈압 및 혈액 내 생활습관병 위험 지표 등의 변화를 분석 및 비교하였다. 20대 성인남녀를 대상으로 체중 감량을 위해 wash-out 기간인 중간 2주를 제외하고 개인 필요 열량의 30%를 줄인 low GL 식사와 high GL 식사를 각 2주간 제공하였다. Low GL 식사와 high GL 식사의 효과를 비교한 결과 low GL 식사가 high GL 식사에 비해 체중 (p < 0.001), 체지방량 (p = 0.024), 체질량지수 (p < 0.001)에서 유의적으로 감소량이 더 컸다. 하지만 혈압, 혈액 내 비만 질환 위험 지표에서는 유의한 차이가 없었다. Low GL 식사의 전·후를 비교한 결과 체중, 체지방량, 체질량지수, 체지방률, 이완기 혈압, 중성지방, 총콜레스테롤, HDL-콜레스테롤, LDL-콜레스테롤, 공복혈당, C-peptide HOMA 지수가, high GL 식사에서는 체중, 체지방량, 체질량지수, 총콜레스테롤, HDL-콜레스테롤, 공복혈당, C-peptide, C-peptide HOMA 지수에서 각 식사 전보다 후에 유의적으로 감소되었다. 또한 실험 식사 섭취 전과 섭취 후를 비교한 결과 체중, 체지방량, 체질량지수, 체지방률, 혈압 (수축기, 이완기), 총콜레스테롤, HDL-콜레스테롤, LDL-콜레스테롤, 공복혈당, 당화혈색소, C-peptide, C-peptide HOMA 지수가 모두 유의적으로 감소되었다. 본 연구 결과 체중감량 및 생활습관병 위험을 줄이기 위해서는 단순히 섭취 열량을 낮추기보다는 열량과 함께 당부하량을 고려하여 섭취하는 것이 체중을 감소시키는 데에 더 효과적일 것으로 사료된다.
이 연구의 목적은 공업계열 전문계고등학교의 디지털 논리 회로 과목에서 '조합 논리 회로'단원에 시뮬레이션 수업을 적용하여 학생들의 디지털 논리회로에 대한 학업성취도에 미치는 효과를 알아보는 데 있다. 이 연구를 위해 경상북도에 소재한 공업계열 전문계고등학교 3학년 2개 학급을 실험 집단과 통제 집단으로 선정하였고, 3개의 영가설을 설정하여 검증하였다. 실험 설계는 이질통제집단 전후검사 설계를 사용하였다. 실험은 총 6차시에 걸쳐 이루어 졌으며, 실험 집단에는 PSpice 시뮬레이션 수업을 적용한 후 브레드보드를 이용한 실습을 실시하였고, 통제 집단에는 전통적인 강의식 수업을 적용한 후 브레드보드를 이용한 실습을 실시하였다. 자료의 통계 처리는 SPSSWIN (ver 10.0) 프로그램을 사용하였고, 두 집단의 평균 차이가 통계적으로 유의미한지 알아보기 위해 유의수준 .05로 설정하여 독립표본 t-검증을 하였다. 이 연구에서 얻어진 결론은 다음과 같다. 첫째, 시뮬레이션 수업은 집단 유형에 따른 학업성취 전체 영역에 대해서는 효과적인 수업 방법이라고 할 수 없다. 그러나 심동적 영역에서는 학업 성취도 향상에 효과적이었다. 둘째, 시뮬레이션 수업은 학업 수준에 따른 학업성취 전체 영역에 대해서는 효과적인 수업 방법이라고 할 수 없다. 그러나 인지적 영역과 심동적 영역에서는 중 하위 집단에, 정의적 영역에서는 하위 집단에 효과적이었다. 셋째, 시뮬레이션 수업은 실습 소요 시간의 단축에 효과적인 수업 방법이라고 할 수 없다. 그러나 하위 집단의 실습 소요 시간의 단축에는 효과적이었다. 이상의 연구 결과 시뮬레이션 수업은 주로 심동적 영역에서 효과적이었고, 상위 집단보다는 하위 집단으로 갈수록 학업 성취에 있어서 효과적이라는 것을 알 수 있었다. 그러므로 다양한 교수 학습 방법을 활용함으로써 학습 효과를 높일 수 있다는 점을 시사해 준다.
Digital Convergence means integration between industry, technology, and contents, and in marketing, it usually comes with creation of new types of product and service under the base of digital technology as digitalization progress in electro-communication industries including telecommunication, home appliance, and computer industries. One can see digital convergence not only in instruments such as PC, AV appliances, cellular phone, but also in contents, network, service that are required in production, modification, distribution, re-production of information. Convergence in contents started around 1990. Convergence in network and service begins as broadcasting and telecommunication integrates and DMB(digital multimedia broadcasting), born in May, 2005 is the symbolic icon in this trend. There are some positive and negative expectations about DMB. The reason why two opposite expectations exist is that DMB does not come out from customer's need but from technology development. Therefore, customers might have hard time to interpret the real meaning of DMB. Time is quite critical to a high tech product, like DMB because another product with same function from different technology can replace the existing product within short period of time. If DMB does not positioning well to customer's mind quickly, another products like Wibro, IPTV, or HSPDA could replace it before it even spreads out. Therefore, positioning strategy is critical for success of DMB product. To make correct positioning strategy, one needs to understand how consumer interprets DMB and how consumer's interpretation can be changed via communication strategy. In this study, we try to investigate how consumer perceives a new product, like DMB and how AD strategy change consumer's perception. More specifically, the paper segment consumers into sub-groups based on their DMB perceptions and compare their characteristics in order to understand how they perceive DMB. And, expose them different printed ADs that have messages guiding consumer think DMB in specific ways, either cellular phone or personal TV. Research Question 1: Segment consumers according to perceptions about DMB and compare characteristics of segmentations. Research Question 2: Compare perceptions about DMB after AD that induces categorization of DMB in direction for each segment. If one understand and predict a direction in which consumer perceive a new product, firm can select target customers easily. We segment consumers according to their perception and analyze characteristics in order to find some variables that can influence perceptions, like prior experience, usage, or habit. And then, marketing people can use this variables to identify target customers and predict their perceptions. If one knows how customer's perception is changed via AD message, communication strategy could be constructed properly. Specially, information from segmented customers helps to develop efficient AD strategy for segment who has prior perception. Research framework consists of two measurements and one treatment, O1 X O2. First observation is for collecting information about consumer's perception and their characteristics. Based on first observation, the paper segment consumers into two groups, one group perceives DMB similar to Cellular phone and the other group perceives DMB similar to TV. And compare characteristics of two segments in order to find reason why they perceive DMB differently. Next, we expose two kinds of AD to subjects. One AD describes DMB as Cellular phone and the other Ad describes DMB as personal TV. When two ADs are exposed to subjects, consumers don't know their prior perception of DMB, in other words, which subject belongs 'similar-to-Cellular phone' segment or 'similar-to-TV' segment? However, we analyze the AD's effect differently for each segment. In research design, final observation is for investigating AD effect. Perception before AD is compared with perception after AD. Comparisons are made for each segment and for each AD. For the segment who perceives DMB similar to TV, AD that describes DMB as cellular phone could change the prior perception. And AD that describes DMB as personal TV, could enforce the prior perception. For data collection, subjects are selected from undergraduate students because they have basic knowledge about most digital equipments and have open attitude about a new product and media. Total number of subjects is 240. In order to measure perception about DMB, we use indirect measurement, comparison with other similar digital products. To select similar digital products, we pre-survey students and then finally select PDA, Car-TV, Cellular Phone, MP3 player, TV, and PSP. Quasi experiment is done at several classes under instructor's allowance. After brief introduction, prior knowledge, awareness, and usage about DMB as well as other digital instruments is asked and their similarities and perceived characteristics are measured. And then, two kinds of manipulated color-printed AD are distributed and similarities and perceived characteristics for DMB are re-measured. Finally purchase intension, AD attitude, manipulation check, and demographic variables are asked. Subjects are given small gift for participation. Stimuli are color-printed advertising. Their actual size is A4 and made after several pre-test from AD professionals and students. As results, consumers are segmented into two subgroups based on their perceptions of DMB. Similarity measure between DMB and cellular phone and similarity measure between DMB and TV are used to classify consumers. If subject whose first measure is less than the second measure, she is classified into segment A and segment A is characterized as they perceive DMB like TV. Otherwise, they are classified as segment B, who perceives DMB like cellular phone. Discriminant analysis on these groups with their characteristics of usage and attitude shows that Segment A knows much about DMB and uses a lot of digital instrument. Segment B, who thinks DMB as cellular phone doesn't know well about DMB and not familiar with other digital instruments. So, consumers with higher knowledge perceive DMB similar to TV because launching DMB advertising lead consumer think DMB as TV. Consumers with less interest on digital products don't know well about DMB AD and then think DMB as cellular phone. In order to investigate perceptions of DMB as well as other digital instruments, we apply Proxscal analysis, Multidimensional Scaling technique at SPSS statistical package. At first step, subjects are presented 21 pairs of 7 digital instruments and evaluate similarity judgments on 7 point scale. And for each segment, their similarity judgments are averaged and similarity matrix is made. Secondly, Proxscal analysis of segment A and B are done. At third stage, get similarity judgment between DMB and other digital instruments after AD exposure. Lastly, similarity judgments of group A-1, A-2, B-1, and B-2 are named as 'after DMB' and put them into matrix made at the first stage. Then apply Proxscal analysis on these matrixes and check the positional difference of DMB and after DMB. The results show that map of segment A, who perceives DMB similar as TV, shows that DMB position closer to TV than to Cellular phone as expected. Map of segment B, who perceive DMB similar as cellular phone shows that DMB position closer to Cellular phone than to TV as expected. Stress value and R-square is acceptable. And, change results after stimuli, manipulated Advertising show that AD makes DMB perception bent toward Cellular phone when Cellular phone-like AD is exposed, and that DMB positioning move towards Car-TV which is more personalized one when TV-like AD is exposed. It is true for both segment, A and B, consistently. Furthermore, the paper apply correspondence analysis to the same data and find almost the same results. The paper answers two main research questions. The first one is that perception about a new product is made mainly from prior experience. And the second one is that AD is effective in changing and enforcing perception. In addition to above, we extend perception change to purchase intention. Purchase intention is high when AD enforces original perception. AD that shows DMB like TV makes worst intention. This paper has limitations and issues to be pursed in near future. Methodologically, current methodology can't provide statistical test on the perceptual change, since classical MDS models, like Proxscal and correspondence analysis are not probability models. So, a new probability MDS model for testing hypothesis about configuration needs to be developed. Next, advertising message needs to be developed more rigorously from theoretical and managerial perspective. Also experimental procedure could be improved for more realistic data collection. For example, web-based experiment and real product stimuli and multimedia presentation could be employed. Or, one can display products together in simulated shop. In addition, demand and social desirability threats of internal validity could influence on the results. In order to handle the threats, results of the model-intended advertising and other "pseudo" advertising could be compared. Furthermore, one can try various level of innovativeness in order to check whether it make any different results (cf. Moon 2006). In addition, if one can create hypothetical product that is really innovative and new for research, it helps to make a vacant impression status and then to study how to form impression in more rigorous way.
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70
The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70