• Investigative Magnetic Resonance Imaging
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• v.26 no.2
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• pp.117-124
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• 2022

Purpose: In this study, we provide a way to assess even a slight effect of exercise on trunk-muscle activity. Materials and Methods: Seven healthy male participants (mean age, 24.7 ± 3.2 years; height, 171.2 ± 9.8 cm; and weight, 63.8 ± 11.9 kg) performed 15 sets of an exercise with 20 repetitions of 90° hip and right-knee flexion while lying supine. The exercise intensity was measured using the 10-point Rating of Perceived Exertion Scale after the first and 15th sets of exercises. Although cross-sectional areas and functional T2 mapping using ultrafast imaging (fast-acquired muscle functional magnetic resonance imaging, fast-mfMRI) have been proposed for imaging to evaluate exercise-induced muscle activity in real time, no previous studies have reported on the evaluation of trunk-muscle activity using functional T2 mapping. As a method for assessing trunk-muscle activity, we compared functional T2 mapping using ultrafast imaging (fast-mfMRI) with cross-sectional areas. Results: Although the muscle cross-sectional areas were increased by the exercise, there was no significant difference at rest. On the other hand, for all sets, the changes in T2 were significant compared with those at rest (P < 0.01). These results demonstrate that T2, calculated from fast-mfMRI images can be used to detect even a small amount of muscle activity induced by acute exercise, which was impossible to do with cross-sectional areas. Conclusion: Fast-mfMRI, which can also display functional information with detailed forms, enabled non-invasive real-time imaging for identifying and evaluating the degree of deep trunk-muscle activity induced by exercise.

• Computers and Concrete
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• v.32 no.4
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• pp.351-363
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• 2023

Reducing the self-weight of reinforced concrete structures problem is discussed in this paper by using two types of self-weight reduction, the first is by using lightweight coarse aggregate (crushed brick) and the second is by using styropor block. Experimental and Numerical studies are conducted on (LWAC) lightweight aggregate reinforced concrete slabs, having styropor blocks with various sizes of blocks and the ratio of shear span to the effective depth (a/d). The experimental part included testing eleven lightweight concrete one-way simply supported slabs, comprising three as reference slabs (solid slabs) and eight as styropor block slabs (SBS) with a total reduction in cross-sectional area of (43.3% and 49.7%) were considered. The holes were formed by placing styropor at the ineffective concrete zones in resisting the tensile stresses. The length, width, and thickness of specimen dimensions were 1.1 m, 0.6 m, and 0.12 m respectively, except one specimen had a depth of 85 mm (which has a cross-sectional area equal to styropor block slab with a weight reduction of 49.7%). Two shear spans to effective depth ratios (a/d) of (3.125) for load case (A) and (a/d) of (2) for load case (B), (two-line monotonic loads) are considered. The test results showed under loading cases A and B (using minimum shear reinforcement and the reduction in cross-sectional area of styropor block slab by 29.1%) caused an increase in strength capacity by 60.4% and 54.6 % compared to the lightweight reference slab. Also, the best percentage of reduction in cross-sectional area is found to be 49.7%. Numerically, the computer program named (ANSYS) was used to study the behavior of these reinforced concrete slabs by using the finite element method. The results show acceptable agreement with the experimental test results. The average difference between experimental and numerical results is found to be (11.06%) in ultimate strength and (5.33%) in ultimate deflection.

• Korean Journal of Child Studies
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• v.26 no.5
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• pp.263-279
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• 2005

This study explored the participant roles and the cross-sectional and longitudinal relationships between interpersonal behavior characteristics and bullying/victimization. The subjects were 4th and 5th grade children and instruments were the Participant Roles Scale, Self-Report Coping Scale, Teenage Inventory of Social Skills, and Social Anxiety/Avoidance. They were contacted again one year later. In the distribution of participant roles at Time 1, defender of the victim was highest, then outsider; at Time 2 outsider was the highest and then defender. There was a tendency of gender difference in distribution of participant roles only at Time 1. Males were more in the group of reinforcer; females were more in the group of defender and victim. There were high positive correlations among bully/reinforcer/assistant scores. In the concurrent view, children who used approach coping strategies and showed higher social skills were more likely to be defender. Children who had lower social skills and higher social anxiety and social avoidance were more likely to be victim. In the longitudinal view, children who had developed higher social skills were more likely to be defender. Children who had employed less approach coping strategies and had showed lower social skills and higher social avoidance were more likely to be victim.

• Design & Manufacturing
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• v.13 no.4
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• pp.17-22
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• 2019

Currently, studies on weight reduction and fuel efficiency increase are the most important topics in the automotive industry and many studies are under way. Among them, weight reduction is the best way to raise fuel efficiency and solve environmental pollution and resource depletion. Materials such as aluminum, magnesium and carbon curing materials can be found in lightweight materials. Among these, research on improvement of bonding technology and manufacturing method of materials and improvement of material properties through study of ultrahigh strength steel sheet is expected to be the biggest part of material weight reduction. As the strength of the ultra hight strength steel sheet increases during forming, it is difficult to obtain the dimensional accuracy as the elastic restoring force increases compared to the hardness or high strength steel sheet. It is known that the spring back phenomenon is affected by various factors depending on the raw material and processing process. We have conducted analytical evaluations and studies to analyze the springback that occurs according to the cross-sectional shape of the ultra high tensile steel sheet.

• The Journal of Internal Korean Medicine
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• v.39 no.1
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• pp.44-68
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• 2018

Objective: This study aimed to investigate the trend in the research on breast cancer using traditional Korean medicine (TKM) and establish the direction for further study. Methods: Breast cancer studies using Korean medicine were searched using the Oriental Medicine Advanced Searching Integrated System (OASIS). The search term was 'breast' and there was no restriction in year. The searched studies were analyzed according to the type of research. Results: 1. 83 studies were searched. The types and numbers of study were as follows: 42 were in vitro studies, 5 were in vivo studies, 12 were studies for review, and 27 were clinical research including case reports. 2. Various cell lines such as MCF-7, MDA-MB-231, SKBR3, and MCF-10A were used for in vitro studies. The studies reported a decrease in cell viability, induction of apoptosis, and change of expression in cancer-related genes. In vivo studies also reported induction of apoptosis, and anti-proliferative activity of herbal medicine against the cancer cells. 3. Among the clinical research, 8 were cross-sectional studies, 3 were controlled-trial, and 15 were case reports. The baseline characteristics of breast cancer patients were analyzed in the cross-sectional studies. Interventions such as pharmacopuncture, herbal medicine, massage, Qi gong, acupuncture, electroacupuncture and moxibustion were used in clinical research. 4. Research on the review of breast cancer covered various subjects as follows: herbal medicine, acupuncture, pattern identification of breast cancer in traditional Korean medicine, analysis of previous experimental studies, and clinical trials. Conclusion: We have found the applicability of TKM for treatment of breast cancer through this review. It is necessary to conduct further studies, such as well-designed clinical trials based on the results from experimental research.

• Korean Journal of Child Studies
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• v.29 no.2
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• pp.15-31
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• 2008

This analysis of trends in research on parent-child relationships published in Korean journals focused on child and family studies. Analysis was for research frequency, contents, and methodology. Results showed that 186 research articles on parent-child relationship were published between 2000 and 2006. The main content of research was the effects of parent-child relationships on child development. Most of the studies used methods categorized as quantitative data and cross-sectional surveys.

• Physical Therapy Korea
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• v.23 no.2
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• pp.20-34
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• 2016

Background: It is necessary to find and develop the effective way of intervention for patients with neck pain, since the neck pain is becoming increasingly common throughout the world. To identify the altered motor control in patient with neck pain would be informative to find and develop the effective way of intervention. Objects: The aim of this study was to review literature regarding the altered motor control in patients with neck pain, measured by using surface electromyography (sEMG), ultrasonography, and functional magnetic resonance imaging (fMRI), and to suggest prospective research work on neck pain. Methods: Case-control (neck pain/healthy) studies published between 2004 and 2015 that investigated neck muscle activation, thickness, cross-sectional area, and fat infiltrate were searched in Scopus, PubMed, and ScienceDirect. Twenty-eight articles were included in this study. Results: sEMG, ultrasonography, and fMRI were used complementarily to investigate the altered superficial and deep neck muscle activation, thickness, cross-sectional area, and fat infiltrate in patients with neck pain. They showed the following altered motor control when compared retrospectively with healthy subjects or during specific functional tasks: (1) increased superficial muscle activation, (2) lesser deep muscle thickness, (3) smaller cross-sectional area of the deep muscle, and (4) greater fat infiltrate in deep muscles. In particular, among the women, the office workers showed higher muscle activation of superficial neck muscles during functional tasks, although they did not have neck pain, than those who were not office workers. Conclusion: Studies revealed that patients with neck pain showed an altered motor control when compared with healthy subjects by using various assessment modalities. Understanding this phenomenon would help researchers design an effective intervention for alleviating neck pain or to evaluate the effectiveness of the intervention. In addition, we recommend that female office workers take measures to care for their necks before developing neck pain.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2621-2626
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• 2013

Background: To review the peer reviewed literature on the psychological aspects of the prostate cancer experience of men in Asia. Materials and Methods: Medline and PsycINFO, CINAHL, ProQuest, and Web of Science (1999 - November Week 4, 2012) were searched. Inclusion criteria were: included men with prostate cancer and/or their partners or caregivers who identify as Asian recruited in an Asian country; and assessed health-related quality of life, psychological and social adjustment relating to prostate cancer and published in English after $1^{st}$ January 1999 and prior to $30^{th}$ November, 2012. Study aims; design; quality; level of evidence, and key results were assessed. Results: 43 articles met all inclusion criteria and were retained for initial review. Of these most focussed on health-related QOL with only five evidence Level IV studies from Japan and Taiwan including a specific psychological focus. Of these, one was a cross-sectional case control study; three were cross-sectional descriptive quantitative designs; one was a cross-sectional descriptive qualitative study. From the data available, a substantive sub group of men with prostate cancer (approximately one third) in these countries experience clinically high psychological distress and decision regret. Conclusions: Research on the psychological needs of men with the increasingly prevalent condition of prostate cancer in Asian countries is scant with only a small number of low level evidence descriptive studies identified. Future research to underpin the development and evaluation of effective and culturally relevant psychological and supportive care interventions for such men is urgently needed.

• Korean Journal of Community Nutrition
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• v.28 no.4
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• pp.282-292
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• 2023

Objectives: Bone health in early adulthood, as individuals approach peak bone mass, plays a critical role in preventing osteoporosis later in life. This study aimed to investigate the associations between lifestyle and dietary factors, anthropometric measurements, and urinary bone resorption markers in young adults. Methods: A cross-sectional study was conducted with 100 healthy Korean adults (50 men and 50 women) in their 20s and early 30s. Bone mineral density (BMD), anthropometric measurements, dietary intake (24-hour recall), and urinary bone resorption indicators (deoxypyridinoline and N-terminal telopeptide of type I collagen) were analyzed. Variables were compared between the osteopenia and osteoporosis groups (OSTEO group: 30% men and 60% women) and the healthy control group. Results: Men in the OSTEO group were significantly taller than those in the control group (P < 0.05). Women in the OSTEO group had significantly lower body weight and body composition (muscle and body fat) than those in the normal group (P < 0.01). Men in the OSTEO group had a significantly higher intake of animal calcium (Ca) than those in the normal group (P < 0.05). Women in the OSTEO group had significantly higher dietary fiber, vitamin A, Ca, plant Ca, and potassium intake than did those in the normal group (P < 0.05). There were no significant differences in caffeinated beverage consumption, eating habits, or urinary bone resorption indicators between the OSTEO and control groups of either sex. Conclusions: In our study of young South Korean adults, we observed low bone density levels, with particularly low BMD in taller men and underweight women. We found a higher nutrient intake in the OSTEO group, indicating the possibility of reverse causality, a phenomenon often found in cross-sectional studies. Therefore, there is a need to further elucidate dietary factors related to osteoporosis in young adults through prospective cohort studies involving a larger population.

• Steel and Composite Structures
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• v.52 no.3
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• pp.327-341
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• 2024

This paper is the first in a series of articles dealing with the study and analysis of imperfections in thin-walled, cold-formed steel sections with modified cross-sectional shapes. A study was conducted, using 3D scanning techniques, to determine the most vulnerable geometric imperfections in the profiles. Based on a review of the literature, it has been determined that few researchers are studying thin-walled sections with modified cross-sectional shapes. Each additional bend in the section potentially generates geometric imperfections. Geometric imperfections significantly affect the resistance to loss of stability, which is crucial when analyzing thin-walled structures. In addition, the most critical locations along the length where these imperfections occur were determined. Based on the study, it was found that geometric imperfections cause a reduction in critical load. It should be noted that the tests performed are preliminary studies, based on which a program of further research will be developed. In addition, the article presents the current state of knowledge in the authors' field of interest. The future objective is to ascertain if these imperfections could potentially contribute positively to structural integrity. This enhanced understanding may pave the way for novel methodologies in structural engineering, wherein imperfections are viewed not solely as flaws but also as elements that could enhance the end product.