• Title/Summary/Keyword: Repeated impact test

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Effects of Quercetin and Mannitol on Erythropoietin Levels in Rats Following Acute Severe Traumatic Brain Injury

  • Kalemci, Orhan;Aydin, Hasan Emre;Kizmazoglu, Ceren;Kaya, Ismail;Yilmaz, Hulya;Arda, Nuri M
    • Journal of Korean Neurosurgical Society
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    • v.60 no.3
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    • pp.355-361
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    • 2017
  • Objective : The aim of this study to investigate the normal values of erythropoietin (EPO) and neuroprotective effects of quercetin and mannitol on EPO and hematocrit levels after acute severe traumatic brain injury (TBI) in rat model. Methods : A weight-drop impact acceleration model of TBI was used on 40 male Wistar rats. The animals were divided into sham (group I), TBI (group II), TBI+quercetin (50 mg/kg intravenously) (group III), and TBI+mannitol (1 mg/kg intravenously) (group IV) groups. The malondialdehyde, glutathione peroxidase, catalase, EPO, and hematocrit levels were measured 1 and 4 hour after injury. Two-way repeated measures analysis of variance and Tukey's test were used for statistical analysis. Results : The malondialdehyde levels decreased significantly after administration of quercetin and mannitol compared with those in group II. Catalase and glutathione peroxidase levels increased significantly in groups III and IV. Serum EPO levels decreased significantly after mannitol but not after quercetin administration. Serum hematocrit levels did not change significantly after quercetin and mannitol administration 1 hour after trauma. However, mannitol administration decreased serum hematocrit levels significantly after 4 hour. Conclusion : This study suggests that quercetin may be a good alternative treatment for TBI, as it did not decrease the EPO levels.

Use of repeat anterior maxillary distraction to correct residual midface hypoplasia in cleft patients

  • Richardson, Sunil;Krishna, Shreya;Bansal, Avi
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.43 no.6
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    • pp.407-414
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    • 2017
  • Objectives: The study was designed to evaluate the efficacy of performing a second, repeat anterior maxillary distraction (AMD) to treat residual cleft maxillary hypoplasia. Materials and Methods: Five patients between the ages of 12 to 15 years with a history of AMD and with residual cleft maxillary hypoplasia were included in the study. Inclusion was irrespective of gender, type of cleft lip and palate, and the amount of advancement needed. Repeat AMD was executed in these patients 4 to 5 years after the primary AMD procedure to correct the cleft maxillary hypoplasia that had developed since the initial procedure. Orthopantomogram (OPG) and lateral cephalograms were taken for evaluation preoperatively, immediately after distraction, after consolidation, and one year postoperatively. The data obtained was tabulated and a Mann Whitney U-test was used for statistical comparisons. Results: At the time of presentation, a residual maxillary hypoplasia was observed with a well maintained distraction gap on the OPG which ruled out the occurrence of a relapse. Favorable movement of the segments without any resistance was seen in all patients. Mean maxillary advancement of 10.56 mm was achieved at repeat AMD. Statistically significant increases in midfacial length, SNA angle, and nasion perpendicular to point A distance was achieved (P=0.012, P=0.011, and P=0.012, respectively). Good profile was achieved for all patients. Minimal transient complications, for example anterior open bite and bleeding episodes, were managed. Conclusion: Addressing the problem of cleft maxillary hypoplasia at an early age (12-15 years) is beneficial for the child. Residual hypoplasia may develop in some patients, which may require additional corrective procedures. The results of our study show that AMD can be repeated when residual deformity develops with the previous procedure having no negative impact on the results of the repeat procedure.

Impact of multiple firings and resin cement type on shear bond strength between zirconia and resin cements

  • Oguz, Ece Irem;Ozgur, Merve Erdog;Sungur, Sercan;Uctasli, Sadullah
    • The Journal of Advanced Prosthodontics
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    • v.12 no.4
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    • pp.197-203
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    • 2020
  • PURPOSE. The aim of this study was to evaluate the effect of multiple firings on the bond strength between yttriatetragonal zirconia polycrystals (Y-TZP) and 2 types of resin cements. MATERIALS AND METHODS. Sixty 3Y-TZP specimens (LAVA Frame Multi) were divided into 3 groups depending on the following firing procedures: (1) 2-firing cycles, (2) 5-firing cycles, (3) 10-firing cycles. Two samples from each group were investigated by using SEM to determine the morphological changes. All specimens were treated with 125 ㎛ airborne-particle abrasion and the surface roughness of each specimen was measured. The specimens from each firing group were then further divided into 2 subgroups (n = 9) to apply 2 types of resin cement (MDP-free resin cement: RelyX Unicem-RU, and MDP containing resin cement: Panavia F 2.0-PA). The shear bond strength (SBS) test was performed and failure types of all the debonded specimens were classified by using a stereomicroscope as adhesive, cohesive, and mixed. The statistical analysis of surface roughness and SBS data were performed by using 1-way ANOVA and 2-way ANOVA followed by Tukey-HSD tests (α=.05). Failure modes were calculated as a percentage for each group. RESULTS. The bond strength of RU and PA to the specimens obtained with 2 firings were not statistically different from each other (P=.1). However, the SBS values of PA were found to be significantly higher than RU for the specimens obtained with 5 and 10 firing cycles (P=.001 and P=.02, respectively). Surface roughness analysis revealed no statistical difference between groups (P=.2). The SEM analysis of samples fired 5- and 10- times showed irregularities and boundary loss in zirconia grains, and empty spaces between zirconia grains. CONCLUSION. The bond strength of PA cement was higher than that of RU to the zirconia subjected to repeated firings (5 and 10 firing cycles). When zirconia is subjected to multiple firings, using MDP-containing resin cement can be recommended.

Development and Analysis of the Effects of Caregiver Training Program on Aggressive Behavior m Elders with Cognitive Impairment

  • Oh Heeyaung;Hur Myung-Haeng;Eom Miran
    • Journal of Korean Academy of Nursing
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    • v.35 no.4
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    • pp.745-753
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    • 2005
  • Purpose. The purposes of this study were to 1) describe the type and frequency of aggressive behavior of cognitively impaired nursing home resident, 2) develop a caregiver training program on prevention and management of aggressive behavior, 3) examine the effects of caregiver training program on the incidence of aggressive behavior of cognitively impaired nursing home resident, and 4) examine the effects of caregiver training program on nursing staff's aggressive behavior management skills. Methods. One-group, time series, quasi-experimental design with a pre-test and two post- tests was used. Data were collected from cognitively impaired home residents (N = 32) and nursing staff (N = 36) in a proprietary nursing home using Ryden Aggression Scale I, II, and Aggressive Behavior Management Scale. Data were entered and analyzed by descriptive statistics and repeated measures ANOVA. Results. Incidence of aggressive behavior was high with a mean score of 3.09 (SD = 3.11) at baseline. Caregiver training program was developed based on Progressively Lowered Stress Threshold (PLST) model and gerontological and psychiatric literature. The mean scores of aggressive behavior at baseline, Post I, and II did not differ significantly although the difference approached to the significant level (F = 2.925, p = .066). Nursing staff's aggressive behavior management skills increased at Post I, and at Post II when compared to baseline, and the difference was significant (F=12.736, p=<.00l). Conclusion. Caregiver training program showed potential impact on reduction of aggressive behavior in elders with cognitive impairment and was effective in increasing nursing staff's aggressive behavior management skills.

Biomechanical Analysis of Wearing Carbon Nanotube-Based Insole during Drop Landing (탄소나노튜브 인솔 착용에 따른 드롭 착지 동작의 생체역학적 분석)

  • Chae, Woen-Sik;Jung, Jae-Hu;Lee, Haeng-Seob
    • Korean Journal of Applied Biomechanics
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    • v.22 no.4
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    • pp.429-435
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    • 2012
  • The purpose of this study was to determine the biomechanical effect of wearing carbon nanotube-based insole on cushioning and muscle tuning during drop landing. Twenty male university students(age: $21.2{\pm}1.5yrs$, height: $175.4{\pm}4.7cm$, weight: $70.2{\pm}5.8kg$) who have no musculoskeletal disorder were recruited as the subjects. Average axial strain, average shear strain, inversion angle, linear velocity, angular velocity, vertical GRF and loading rate were determined for each trial. For each dependent variable, a one-way analysis of variance(ANOVA) with repeated measures was performed to test if significant difference existed among different three conditions(p<.05). The results showed that Average axial strain of line 4 was significantly less in CNT compared with EVA and PU during IP phase. The average shear strain was less in CNT compared with EVA and PU during other phases. The inversion angle was increased in CNT compared with EVA and PU during all phase. In linear velocity, angular velocity, vertical GRF and loading rate, there were no significant difference between the three groups. This result seems that fine particle of carbon nanotube couldn't make geometric form which can absolve impact force by increasing density through eliminating voids of forms. Thus, searching for methods that keep voids of forms may play a pivotal role in developing of insole. This has led to suggestions of the need for further biomechanical analysis to these factors.

The Impact of Fractional Flow Reserve on Clinical Outcomes after Coronary Artery Bypass Grafting: A Meta-analysis

  • Yoonjin, Kang;Heeju, Hong;Suk Ho, Sohn;Myoung-jin, Jang;Ho Young, Hwang
    • Journal of Chest Surgery
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    • v.55 no.6
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    • pp.442-451
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    • 2022
  • Background: This meta-analysis was conducted to evaluate the effect of fractional flow reserve (FFR) on clinical outcomes after coronary artery bypass grafting (CABG). Methods: Five online databases were searched for studies that (1) enrolled patients who underwent isolated CABG or CABG with aortic valve replacement and (2) demonstrated the effect of an FFR-guided strategy on major adverse cardiac events (MACE) after surgery based on a randomized controlled trial or adjusted analysis. MACE included cardiac death, acute myocardial infarction (MI), and repeated revascularization. The primary outcomes were all MACE outcomes and a composite of all-cause death and MI, and the secondary outcomes were the individual MACE outcomes. Publication bias was assessed using a funnel plot and the Egger test. Results: Six articles (3 randomized and 3 non-randomized studies: n=1,027) were selected. MACE data were extracted from 4 studies. The pooled analyses showed that the risk of MACE was not significantly different between patients who underwent FFR-guided CABG and those who underwent angiography-guided CABG (hazard ratio [HR], 0.80; 95% CI, 0.57-1.12). However, the risk of the composite of death or MI was significantly lower in patients undergoing FFR-guided CABG (HR, 0.62; 95% CI, 0.41-0.94). The individual MACE outcomes were not significantly different between FFR-guided and angiography-guided CABG. Conclusion: FFR-guided CABG might be beneficial in terms of the composite outcome of death or MI compared with angiography-guided CABG although data are limited.

Effects of Audio-visual Entertainment and Soft Tissue Mobilization on Pressure Pain Thresholds, Psychophysiological parameters, and Brain waves in University Students with Tension-type Headache (긴장성 두통이 있는 대학생들에게 시청각적 엔터테인먼트와 연부조직 가동술이 압력통각역치, 바이오피드백, 뇌파에 미치는 영향)

  • Jung, Dae-In;Lee, Eun-Sang;Kim, Hyun-Joong
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.7
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    • pp.539-548
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    • 2020
  • TTH(tension-type headache) is the most common primary headache among adults. Long-term headaches cause chronic headaches and have a better impact on daily life. The purpose of this study is to compare the contributions to TTH through AVE(audio-visual entertainment) and STM(soft tissue mobilization) suitable for management of pathogenic and psychogenic factors of TTH. The participants of this study were from 30 people who complained of intermittent or persistent headaches for more than 6 months, and 10 participants each in the AVE group, STM group, and AVE plus STM group. In the assigned group, a total of 12 sessions were performed three times a week for 4 weeks after the baseline, followed by post-test. Outcome measures measured PPTs(pressure pain thresholds), psychophysiological parameters, and EEG(electroencephalogram). The measured results were analyzed for interaction between time and group through a two way rmANOVA(repeated measurement variance analysis). As a result of the PPTs, interaction was found in the results of the right trapezius (p<.05), and the more improvement was observed in the AVE group. Therefore, through AVE based on psychological factors rather than direct access to the muscles of pathogenic factors, a positive impact on the PPTs was shown, but the average value of the psychophysiological parameters and brain waves that were not statistically significant. The amount of change was observed. Through this, it is suggested that audio-visual stimulation could be considered in the management of TTH.

Diet intervention to improve cardiovascular risk factors among Iranian postmenopausal women

  • Abedi, Parvin;Lee, Mary Huang-Soo;Kandiah, Mirnalini;Yassin, Zaitun;Shojaeezade, Davood;Hosseini, Mostafa;MSc, Reza Malihi
    • Nutrition Research and Practice
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    • v.4 no.6
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    • pp.522-527
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    • 2010
  • Cardiovascular disease is a leading cause of death and disability and remains so in the future. The aim of this study was to detect the impact of a 6-month diet intervention on cardiovascular risk factors in postmenopausal Iranian women. It was a randomized controlled trial that carried out in the East Health Clinic in Ahvaz-Iran. This study started on June 2007 and was completed on May 2008. A total 64 healthy postmenopausal women recruited and randomly assigned to the intervention group (35) and control (29). Over the six months follow-up, the intervention group received five educational sessions (two face to face and three lecture discussion classes with slide demonstration) at the first month. These sessions were about menopause, cardiovascular disease and healthy diet. Every participant in the intervention group received one face to face education session at the $3^{rd}$ month, and also received a telephone call at the end of each month starting with the second month to remain on the diet. Pre-intervention and post-intervention anthropometric measurements, blood pressure, blood lipids and dietary intake were assessed. Data analyzed using the SPSS version 15. Descriptive (means and SD), univariate (paired-t test, Chi-Square and Independent T-test) and multivariate (GLM Repeated Measure) statistics were used. Participants in the diet group had significantly lower weight (-0.9 kg), body mass index (-0.4 $kg/m^2$), and fasting blood sugar (-4.5 mg/dl). The diet group significantly increased their daily intake of fiber (+2.3 g, P=0.05), decreased their intake of sodium (-28 mg, P=0.04), and consumption of fruit and vegetable ${\geq}$ 5 serving a day (80%, P=0.03) compared to the control group. Post menopausal women are at a greater risk for cardiovascular disease. Healthy diet using educational intervention can be an effective means of reducing cardiovascular risk in postmenopausal women.

A Study on Durability Improvement of Breech Block for 30mm Automatic Gun (30mm 자동포용 폐쇄기의 내구성 향상에 관한 연구)

  • Park, Young Min;Kim, Sung Hoon;Noh, Sang Wan;Kim, Sung Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.47-53
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    • 2020
  • The purpose of this study was to increase product reliability by improving the durability of the breech block for a 30mm Automatic Gun. The breech block is a key component of a gun that functions as chambering, closing, and extracting. The breech block requires high reliability, which needs to be improved because cracks of a breech block can occur early in operation. Cause analysis confirmed that the crack is caused by repeated impacts. Therefore, the following improvement measures were studied, and the effects were demonstrated using a firing test. The energy of impact absorption was increased by changing the material, and the stress concentration was mitigated by increasing the value of R. In addition, the fatigue life was increased by adding Shot-peening, deleting chromium plating, and changing the forging method. The firing test did not show firing trouble for up to 5,000 rounds. The start timing of the crack was delayed, and the depth was small. Therefore, the improved product was more durable than the existing product. This study can be used as a useful reference when assessing the improvement of the durability of similar products, life study, and criteria for crack acceptance.

Effects of Gaussian Magnetic Therapy on Body Temperature in Elderly Women with Delayed Onset Muscle Soreness (노년기 지연성 근육통증에 대한 가우스 자기장 치료가 신체 체열 변화에 미치는 영향)

  • Shin, Won
    • The Journal of the Korea Contents Association
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    • v.19 no.7
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    • pp.538-545
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    • 2019
  • The purpose of this study was to analyze the change of body temperature and pain by application of Gaussian magnetic for the elderly delayed muscle pain. For the purpose, we selected 15 elderly women(age;$69.47{\pm}1.60$) and conducted repeated experiments. The Gaussian magnetic field area was divided into three areas (1000G, 1500G, 2000G). The applying arbitrarily manufactured magnetic field wristbands changes of body heat and pain before and after wearing Gaussian magnetic were measured and collected data were analyzed using SPSS 19.0. To examine the pre-and post-treatment differences by treatment areas, we conducted paired t-test. Group differences and interaction effects were analyzed using two-way ANOVA and Duncan post hoc tests. The significance level was set to ${\alpha}=.05$. The results are as follows. The change of body heat by the Gaussian magnetic field area showed significant differences in all three groups(P<.05). There were also significant differences in the results of group interactions and in the delayed muscle pain scale between groups(P<.05). The area with the largest difference appeared in the area of 1500G field. The 1000G-1500G Gauss field is considered to be the most ideal magnetic field for body heat and muscle pain changes. In conclusion, the Gaussian magnetic field of 1000G-1500G may affect body temperature and muscle pain in the elderly, and may have a significant impact on the quality of life in old age.