• Clinical and Experimental Reproductive Medicine
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• 제48권4호
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• pp.316-321
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• 2021

Objective: Amino acids can protect sperm structure in cryopreservation due to their antioxidant properties. Therefore, the present study aimed to investigate the protective effect of L-carnitine (LC) and N-acetyl cysteine (NAC) on motility parameters, plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), DNA damage, and human sperm intracellular reactive oxygen species (ROS) during vitrification. Methods: Twenty normal human sperm samples were examined. Each sample was divided into six equal groups: LC (1 and 10 mM), NAC (5 and 10 mM), and cryopreserved and fresh control groups. Results: The groups treated with LC and NAC showed favorable findings in terms of motility parameters, DNA damage, and MMP. Significantly higher levels of intracellular ROS were observed in all cryopreserved groups than in the fresh group (p≤0.05). The presence of LC and NAC at both concentrations caused an increase in PMI, MMP, and progressive motility parameters, as well as a significant reduction in intracellular ROS compared to the control group (p≤0.05). The concentrations of the amino acids did not show any significant effect. Conclusion: LC and NAC are promising as potential additives in sperm cryopreservation.

• 소성∙가공
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• 제30권3호
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• pp.109-118
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• 2021

Recently, there has been an increased interest in the remanufacturing of mechanical parts using metal additive manufacturing processes in regards to resource recycling and carbon neutrality. DED (directed energy deposition) process can create desired metallic shapes on both even and uneven substrate via line-by-line deposition. Hence, DED process is very useful for the repair, retrofit and remanufacturing of mechanical parts with irregular damages. The objective of the current paper is to investigate the effects DED process parameters, including the effects of power and the scan speed of the laser, on deposition and residual stress characteristics for remanufacturing of mechanical parts using experiments and finite element analyses (FEAs). AISI 1045 is used as the substrate material and the feeding powder. The characteristic dimensions of the bead shape and the heat affected zone (HAZ) for different deposition conditions are obtained from the experimental results. Efficiencies of the heat flux model for different deposition conditions are estimated by the comparison of the results of FEAs with those of experiments in terms of the width and the depth of HAZ. In addition, the influence of the process parameters on residual stress distributions in the vicinity of the deposited region is investigated using the results of FEAs. Finally, a suitable deposition condition is predicted in regards to the bead formation and the residual stress.

• Clinical and Experimental Reproductive Medicine
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• 제49권2호
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• pp.110-116
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• 2022

Objective: Sperm vitrification leads to the production of reactive oxygen species (ROS) that can damage the functional parameters of sperm. The present study aimed to investigate the antioxidant effect of Nigella sativa extract on motility, plasma membrane function, mitochondrial membrane potential (MMP), DNA damage, and intracellular ROS production. Methods: A total of 20 sperm samples were used. Samples were divided into six experimental groups, including groups with aqueous extract from N. sativa seeds at concentrations of 1% to 6%, a cryopreserved control group, and a fresh control group. Results: Statistical analysis showed significantly higher total sperm motility at concentrations of 3% to 6% than in the vitrified semen control group. Additionally, progressive motility and all motion characteristics at all concentrations were significantly higher than in the vitrified semen control group. The presence of N. sativa seed extract also improved the quality of the sperm parameters assayed in all experimental groups (1%-6%; intracellular ROS production, DNA damage, MMP, and sperm membrane function) compared to the control group. Conclusion: Higher concentrations of N. sativa led to improvements in all sperm parameters and sperm quality. These findings indicate that N. sativa seed extract is effective for improving the quality of sperm after vitrification.

• Physical Therapy Rehabilitation Science
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• 제11권1호
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• pp.105-112
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• 2022

Objective: Nonspecific low back pain (NS-LBP) causes pain and disability, affecting the neuromuscular system and altering gait patterns. The purpose of this study is to investigate the effect of improvement of low back pain symptoms through physical therapy on foot pressure and spatiotemporal gait parameters. Design: A pilot study. Methods: Participants received manual therapy and supervised therapeutic exercise, which consisted of 12 sessions for 6 weeks. Participants were assessed for pain intensity (a numeric pain rating scale), disability index (oswestry disability index), and spatiotemporal gait parameters before and after intervention. Wilcoxon signed rank test was used to analyze the before-and-after differences in a single group. Results: All seven NS-LBP patients completed the study without dropout. After six weeks of physical therapy, the numeric pain rating scale and oswestry disability index showed significant improvement (Z= -2.388, P=0.017). There was no significant improvement in both static and dynamic conditions in foot pressure (P>0.05). However, in the spatiotemporal gait parameters, there were significant differences in all variables except the right stance phase and left mid stance (P<0.05). Conclusions: In our pilot study, 12 sessions of physical therapy in NS-LBP patients improved gait quilty in spatiotemporal gait parameters. Similarly, it has resulted in clinically positive improvements in pain and disability.

• Clinical and Experimental Reproductive Medicine
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• 제51권2호
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• pp.120-124
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• 2024

Objective: Seasonal variations in semen quality are known to occur in temperate regions, but results regarding tropical areas remain inconclusive. The aim of this study was to determine whether monthly variations in semen parameters are present among men in a tropical region. Methods: Data were retrospectively collected from semen analyses of 3,000 men over a 10-year period, from 2012 to 2022. Analysis of variance and the independent-samples t-test were employed to observe variations in semen parameters throughout the entire period and between months, respectively. Results: The mean±standard deviation sperm concentration was significantly lower in June, at 42.5±31.4 million/mL, compared to other months. The highest sperm concentration was found in March, at 57.8±42.6 million/mL, constituting a mean difference of 15.3 million/mL between the lowest and highest concentrations. The total sperm count displayed a similar pattern of monthly variation, with a difference of 47.2 million between the highest and lowest months. No significant monthly differences were observed in other parameters, such as sperm motility, morphology, and semen volume. Conclusion: Significant monthly variations in sperm concentration and total sperm count were evident in this Sri Lankan population. March, which displayed the highest sperm counts, is in the spring in temperate regions, while the month with the lowest counts, July, is part of the summer. Fluctuations in photoperiod appear to most strongly influence these variations.

• 대한한방내과학회지
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• 제32권4호
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• pp.584-598
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• 2011

Objectives : Functional dyspepsia is a type of disease characterized by bothersome postprandial fullness, early satiation, epigastric pain and burning without structural gastrointestinal disease. The aim of this study was to analyze the characteristics of functional dyspepsia patients and evaluate changes in symptoms, quality of life, and electrogastrography parameters before and after oriental medical interventions. Methods : We recruited forty-six functional dyspepsia patients who visited gastroenterology clinic in the oriental medicine hospital of Kyung Hee University between November 2009 and February 2011. Patients were assessed for their frequency of dyspepsia (based on short form-Leeds Dyspepsia Questionnaire: SF-LDQ), quality of life (based on functional dyspepsia-related quality of life questionnaire: FD-QoL), gastric motility (based on electrogastrography: EGG) on the first visit. Then, the effect of oriental medical interventions was evaluated using EGG on the second visit. Results : The majority of patients had symptoms of nausea and indigestion. The largest decrease in EGG parameters was found in the indigestion group. The frequency of regurgitation and postprandial EGG power % bradygastria showed a significant correlation. Also, significant correlations were found between some items of FD-QoL and some EGG parameters. Compared to the EGG parameters before oriental medical interventions, some parameters after treatment had positive results, implying the improvement of gastric motility disorder. We also found improvement of EGG parameters in both digestant medicinal group and digestant combined with qi-tonifying medicinal group. Conclusions : The results of this study suggest that clinical application of EGG can be an objective diagnostic tool in functional dyspepsia patients visiting oriental medical hospital.

• 국제물리치료학회지
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• 제10권4호
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• pp.1914-1920
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• 2019

Background: Mobilization and cranio-cervical flexion exercise has been reported in reducing pain from cervical part and improving its motor function; also, has been represented that alleviate of neck pain and recover of neck muscles improve the normal gait performance. However, few studies have identified the effects of mobilization and exercise on pain and gait parameters with preceding issues. Objective: To examine the effects or changes of pressure pain threshold (PPT) and gait parameters in patients with chronic neck pain. Design: Cross-Sectional Clinical Trials Methods: Twenty patients with the history of neck pain (>3 months) performed the cervical mobilization and cranio-cervical flexion exercise. Gait parameters were assessed with wireless device and collected data were transmitted to the personal computer via Bluetooth. The PPT was measured posteroanterior direction at the prone position and the mean of subsequent three PPT measurements was used for the final analysis. Results: Both cervical central posteroanterior mobilization (CCPAM) (p<.000) and sling-based cranio-cervical flexion exercise (SBCCFE) (p<.000) group showed a significant increase in the PPT and the gait parameters, cadence (p<.023), was significantly increased in the CCPAM group, however slightly increased in the SBCCFE group. The comparison between the CCPAM and the SBCCFE groups after treatment did not show significant differences for the score on the PPT and gait parameters. Conclusions: This study suggests that CCPAM and SBCCFE increase PPT, cadence, and gait speed.

• Structural Engineering and Mechanics
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• 제68권5호
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• pp.563-573
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• 2018

Temperature-induced responses, such as strains and displacements, are related to the boundary conditions. Therefore, it is required to determine the boundary conditions to establish a reliable bridge model for temperature-induced responses analysis. Particularly, bridge bearings usually present nonlinear behavior with an increase in load, and the nonlinear boundary conditions cause significant effect on temperature-induced responses. In this paper, the bridge nonlinear boundary conditions were simulated as bilinear translational or rotational springs, and the boundary parameters of the bilinear springs were identified based on the measured temperature-induced responses. First of all, the temperature-induced responses of a simply support beam with nonlinear translational and rotational springs subjected to various temperature loads were analyzed. The simulated temperature-induced strains and displacements were assumed as measured data. To identify the nonlinear translational and rotational boundary parameters of the bridge, the objective function based on the temperature-induced responses is then created, and the nonlinear boundary parameters were further identified by using the nonlinear least squares optimization algorithm. Then, a beam structure with nonlinear translational and rotational springs was simulated as a numerical example, and the nonlinear boundary parameters were identified based on the proposed method. The numerical results show that the proposed method can effectively identify the parameters of the nonlinear boundary conditions. Finally, the boundary parameters of a real arch bridge were identified based on the measured strain data and the proposed method. Since the bearings of the real bridge do not perform nonlinear behavior, only the linear boundary parameters of the bridge model were identified. Based on the bridge model and the identified boundary conditions, the temperature-induced strains were recalculated to compare with the measured strain data. The recalculated temperature-induced strains are in a good agreement with the real measured data.

• Geomechanics and Engineering
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• 제37권3호
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• pp.213-222
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• 2024

Determination of jointed rock mass properties plays a significant role in the design and construction of underground structures such as tunneling and mining. Rock mass classification systems such as Rock Mass Rating (RMR), Rock Mass Index (RMi), Rock Mass Quality (Q), and deformation modulus (Em) are determined from the jointed rock masses. However, parameters of jointed rock masses can be affected by the tunnel depth below the surface due to the effect of the in situ stresses. In addition, the geomechanical properties of rocks change due to the effect of metamorphism. Therefore, the main objective of this study is to apply correlation analysis to investigate the relationships between rock mass properties and some parameters related to the depth of the tunnel studied. For this purpose, the field work consisted of determining rock mass parameters in a tunnel alignment (~7.1 km) at varying depths from 21 m to 431 m below ground surface. At the same excavation depths, thirty-seven rock types were also sampled and tested in the laboratory. Correlations were made between vertical stress and depth, horizontal/vertical stress ratio (k) and depth, k and Em, k and RMi, k and point load index (PLI), k and Brazilian tensile strength (BTS), Em and uniaxial compressive strength (UCS), UCS and PLI, UCS and BTS. Relationships were significant (significance level=0.000) at the confidence interval of 95% (r = 0.77-0.88) between the data pairs for the rocks taken from depths greater than 166 m where the ratio of horizontal to vertical stress is between 0.6 and 1.2. The in-situ stress parameters affected rock mass properties as well as metamorphism which affected the geomechanical properties of rock materials by affecting the behavior of minerals and textures within rocks. This study revealed that in-situ stress parameters and metamorphism should be reviewed when tunnel studies are carried out.

• Clinical and Experimental Reproductive Medicine
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• 제51권2호
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• pp.125-134
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• 2024

Objective: Vitamin D deficiency is a major problem for human health worldwide. The mechanisms of vitamin D in the male reproductive system are unknown. After coronavirus disease 2019 (COVID-19) vaccines were developed, doubts were raised about their possible effects on male fertility. Based on vitamin D's function in the immune system, its potential role as an adjuvant for COVID-19 vaccines is intriguing. The aims of this study were to assess the effects of vitamin D first on sperm parameters and sex hormones, and then as an immune adjuvant on sperm parameters and sex hormones after study participants had received their second doses of COVID-19 vaccines. Methods: Phase 1 (before the COVID-19 pandemic) included 72 men with idiopathic infertility, and phase 2 had 64 participants who received two doses of COVID-19 vaccines. Both groups were instructed to take 50,000 IU of vitamin D twice monthly for 3 months. Sperm parameters and sex hormones were assessed pre-and post-supplementation. Results: Regular vitamin D intake for 3 months significantly increased the participants' vitamin D levels (p=0.0001). Both phases showed a positive correlation between vitamin D intake and sperm parameters. Vaccination had no negative effects on sperm parameters and sex hormones. Vitamin D was associated with follicle-stimulating hormone (p=0.02) and testosterone (p=0.0001) in phase 2 after treatment. Conclusion: Our results support vitamin D supplementation as an immune adjunct to COVID-19 vaccination for improving sperm parameters and hormone levels. COVID-19 vaccination is not harmful for male fertility potential, and vitamin D is an effective factor for male fertility.