• Title/Summary/Keyword: surface-activity.

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Changes in Muscle Activity of the Serratus Anterior According to Surface Tilt Angle During Push-up Plus Exercise in Subjects With Winged Scapula

  • Gu, Qian;Kim, Tae-ho;Chun, Jung-genn
    • Physical Therapy Korea
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    • v.26 no.4
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    • pp.29-34
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    • 2019
  • Background: The serratus anterior is one of the most important muscle for maintaining good scapular alignment in the shoulder joint. The pectoralis major and upper trapezius may also compensate for weak serratus anterior muscles. The push-up plus exercise has been identified as the optimal exercise for maximum activation of the serratus anterior. Objects: The purpose of this study was to examine differences in surface electromyography (EMG) activity of upper trapezius, pectoralis major, and serratus anterior muscles during push-up plus exercises on variously angled surfaces in subjects with winged scapula. Methods: Sixteen subjects with winged scapula (male=5, female=11) volunteered for this study. The subjects performed push-up plus exercise on four different tilt angles, namely $0^{\circ}$, $30^{\circ}$, $60^{\circ}$, and $90^{\circ}$. EMG activities in the serratus anterior, upper trapezius, and pectoralis major muscles during performance of push-up plus exercise were measured in all subjects. Data were processed from repeated measures one-way analysis of variance. Results: There was significant difference in the muscle activity of the serratus anterior on the different surface angles (p<.05). The results of the post-hoc analysis showed significantly greater serratus anterior muscle activity on a surface at a $0^{\circ}$ angle than at others tilt angles (p<.05). There was also significant difference in the ratio of serratus anterior to upper trapezius and serratus anterior to pectoralis major across the four surfaces (p<.05), and post-hoc analysis showed significantly greater values on the $0^{\circ}$ surface than on other tilts (p<.05). Conclusion: This study found that performing push-up plus exercises on a flat surface with $0^{\circ}$ and $30^{\circ}$ tilt angle achieves high activation of the serratus anterior muscle for selective strengthening. It can also take into account the sequential application, which is first performed at a $30^{\circ}$ and at a $0^{\circ}$ tilt angle for and effective but not excessive muscle activation.

Comparison of Trunk and Lower Extremity Muscle Activities during Deadlift depending on Support Surface (데드리프트 시 지지면에 따른 몸통 및 하지 근육의 활성도 비교)

  • Jeong, Seyeon;Son, Sangjun;Lee, Hyeongseok;Lee, Jeonghoon;Baek, Jiwon;Yang, Seongbin;Choi, Wonjae;Hong, SoungKyun;Song, Sunhae;Lee, GyuChang
    • PNF and Movement
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    • v.20 no.1
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    • pp.67-72
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    • 2022
  • Purpose: The aim of this study was to compare trunk and lower extremity muscle activity during deadlift on stable - and unstable surfaces. Methods: Twenty healthy men participated in this study. The participants performed deadlift exercise on both a stable surface and an unstable surface. During the deadlift, the activities of the trunk and lower extremity muscle were collected by using electromyography. Results: The results showed that the electromyographic activity of the gluteus maximus significantly increased during deadlift on an unstable surface compared to on a stable surface (p <0.05). However, in the electromyographic activities of the rectus femoris, biceps femoris, and erector spinae, there were no significant differences (p >0.05). Conclusion: The finding that the electromyographic activity of the gluteus maximus increases significantly during deadlift on an unstable surface compared to stable one could be used to develop an efficient exercise program.

Optimization of Hydroxyl Radical Scavenging Activity of Exopolysaccharides from Inonotus obliquus in Submerged Fermentation Using Response Surface Methodology

  • Chen, Hui;Xu, Xiangqun;Zhu, Yang
    • Journal of Microbiology and Biotechnology
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    • v.20 no.4
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    • pp.835-843
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    • 2010
  • The objectives of this study were to investigate the effect of fermentation medium on the hydroxyl radical scavenging activity of exopolysaccharides from Inonotus obliquus by response surface methodology (RSM). A two-level fractional factorial design was used to evaluate the effect of different components of the medium. Corn flour, peptone, and $KH_2PO_4$ were important factors significantly affecting hydroxyl radical scavenging activity. These selected variables were subsequently optimized using path of steepest ascent (descent), a central composite design, and response surface analysis. The optimal medium composition was (% w/v): corn flour 5.30, peptone 0.32, $KH_2PO_4$ 0.26, $MgSO_4$ 0.02, and $CaCl_2$ 0.01. Under the optimal condition, the hydroxyl radical scavenging rate (49.4%) was much higher than that using either basal fermentation medium (10.2%) and single variable optimization of fermentation medium (35.5%). The main monosaccharides components of the RSM optimized polysaccharides are rhamnose, arabinose, xylose, mannose, glucose, and galactose with molar proportion at 1.45%, 3.63%, 2.17%, 15.94%, 50.00%, and 26.81%.

Effects of Drugs on the Stability of Phospholipid Liposomal Membranes (수종 약물이 리포솜 지질막의 안정성에 미치는 영향)

  • Kim, Min;Han, Suk-Kyu;Kim, Chong-Kook
    • YAKHAK HOEJI
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    • v.38 no.6
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    • pp.637-645
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    • 1994
  • The effect of various drugs on the stability of the liposomal membrane of phosphatidylcholine and cholesterol was studied, employing the fluorescence self-quenching method. Calcein was entrapped into the phospholipid small unilamellar vesicles and the leakage of the fluorescence probe was monitored on adding the drug to the system. The results of the experiments showed that phenothiazine derivatives, some potent local anesthetics and surface active agents were very effective in inducing the leakage of calcein from the liposome. The leakage-inducing activity of these drug substances has been ascribed to their surface activity and the perturbation of the liposomal membrane by these substances. On the other hand drug substance with low surface activity or without amphiphilic moieties did not show any effect or only small effect on the leakage of calcein from the liposomes. The effect of lipid concentration on the stability of the liposomes was also investigated to show that the higher concentrations of lipid more drug was required to induce the leakage. The effect of surface charges of vesicles was also studied, and the results showed that the charge on the liposomes enhanced the stability of the liposomes against the leakage-inducing activity of these drug substances.

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Postural Strategy by the Difference of Shoe Heel Height During Quiet Standing on an Unstable Surface (불안정 지지면에서 정적 서기 동안 구두 굽 높이의 변화에 따른 자세 조절 전략)

  • Sagong, Woo-Won;An, Duk-Hyun
    • Physical Therapy Korea
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    • v.21 no.2
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    • pp.28-36
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    • 2014
  • The purpose of this study was to evaluate the changes in the electromyographic (EMG) activity of the trunk and the lower limb muscles during quiet standing on an unstable surface while wearing low-heeled shoes (3 cm), high-heeled shoes (7 cm) and without footwear (0 cm) in 20 young healthy women. The subjects stood on an unstable surface for 30 seconds. We examined the differences in the EMG data of the erector spinae, rectus abdominis, biceps femoris, rectus femoris, tibialis anterior, and the gastrocnemius medialis muscle. A one-way repeated analysis of variance was used to compare the effects of shoe heel height on the EMG activity with the level of significance set at ${\alpha}=.05$. The EMG activity of the erector spinae and the rectus femoris were significantly increased (p<.05) in the subjects who wore elevated heel height, while the tibialis anterior and the gastrocnemius medialis were significantly decreased (p<.05). However, the rectus abdominis and the biceps femoris exhibited no significant difference among the three conditions. The above results indicate that wearing high-heeled shoes may change the postural strategy. The findings of this study suggest that excessive heel height could contribute to an increased fall risk during quiet standing.

$CO_2$ reforming using $TiO_2$/Ni catalysts prepared by atomic layer deposition

  • Kim, Dong-Wun;Kim, Kwang-Dae;Seo, Hyun-Ook;Dey, Nilay Kumar;Kim, Myoung-Joo;Kim, Young-Dok;Lim, Dong-Chan;Lee, Kyu-Hwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.443-443
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    • 2011
  • Atomic layer deposition (ALD) was used to deposit $TiO_2$ on Ni particles, and changes in the catalytic activity of Ni for $CO_2$ reforming of methane (CRM) were studied. In the presence of $TiO_2$ islands on Ni surfaces, the onset temperature of the CRM reaction was lower than that of bare Ni. During the CRM reaction, carbon was deposited on the surface, reducing the catalytic activity of the surface, but $TiO_2$ was able to remove the carbon deposits from the surface. When the Ni surface was completely covered with $TiO_2$, catalytic activity disappeared, indicating that tuning of $TiO_2$ coverage on Ni is important for maximizing the activity of the CRM reaction.

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Analysis Characteristic the Using Surface EMG of Scaling Working of the Dental Hygienist with Upper Body Musculoskeletal Pain (상반신의 근육뼈대계 통증이 치과위생사의 스케일링 작업에 미치는 특성에 대한 표면 근전도 분석)

  • Nam, Kun-Woo;Ha, Mi-Sook
    • Journal of Korean Physical Therapy Science
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    • v.19 no.4
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    • pp.1-6
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    • 2012
  • Purpose : The current research examines the muscle activity that happens during scaling practice subject to 20 dental hygienic students with musculoskeletal pain and then propose a basic data according to the working attitude of the Dental Hygienist. Method : The Nordic-style questionnaire is used to define experimental group with musculoskeletal pain and control group. During the scaling the surface EMG device is used to measure the muscle activity of experimental and control group. Study design : The surface EMG is measure RMS(root mean square) of suboccipital muscle, biceps brachii, upper trapezius, and brachioradialis muscle activity. Results : In the experimental group, the RMS of upper trapezius and brachioradialis is increased during scaling practice(p<0.05), but the control group's RMS is not changed(p>0.05). Conclusion : Musculoskeletal pain may contribute to increase muscle activity of neck & arm during scaling practice. In the future we think there is a need to raise the office efficiency by subjecting to dental hyginiest that are in the clinics and performing experiments.

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Electronic structure and magnetism of catalytic material Pt3Ni surfaces: Density-functional study

  • Sharma, Bharat Kumar;Kwon, Oryong;Odkhuu, Dorj;Hong, Soon Cheol
    • Proceedings of the Korean Magnestics Society Conference
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    • 2012.11a
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    • pp.172-172
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    • 2012
  • A Pt-skin $Pt_3Ni$(111) surface was reported to show high catalytic activity. In this study, we investigated the magnetic properties and electronic structures of the various oriented surfaces of bulk-terminated and Pt-segregated $Pt_3Ni$ by using a first-principles calculation method. The magnetic moments of Pt and Ni are appreciably enhanced at the bulk-terminated surfaces compared to the corresponding bulk values, whereas the magnetic moment of Pt on the Pt-segregated $Pt_3Ni$(111) surface is just slightly enhanced because of the reduced number of Ni neighboring atoms. Spin-decomposed density of states shows that the dz2 orbital plays a dominant role in determining the magnetic moments of Pt atoms in the different orientations. The lowering of the d-band center energy (-2.22 eV to -2.46 eV to -2.51 eV to -2.65 eV) in the sequence of bulk-terminated (100), (110), (111), and Pt-segregated (111) may explain the observed dependence of catalytic activity on surface orientation. Our d-band center calculation suggests that an observed enhanced catalytic activity of a $Pt_3Ni$(111) surface originates from the Pt-segregation.

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Evaluation of the physical properties and antibacterial effects on Candida albicans of denture base resin containing silver sulfadiazine (실버 설파다이아진이 첨가된 의치상용 레진의 Candida albicans에 대한 항균평가 및 물성 평가)

  • Yu-Ri Choi;Min-Kyung Kang
    • Journal of Korean society of Dental Hygiene
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    • v.23 no.6
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    • pp.459-466
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    • 2023
  • Objectives: The purpose of this study was to evaluate the physical properties and antibacterial activity of denture base resin with added silver sulfadiazine. Methods: Specimens were made from self-curing denture base resin and silver sulfadiazine as an inorganic antibacterial agent. For physical evaluation of the specimens, surface roughness, surface hardness, and contact angle were measured. Bacterial growth was assessed by optical densityat 600 nm (OD600) and colony forming units (CFU) measurements to confirm antibacterial activity. Results: There was no significant difference in surface roughness, surface hardness, and contact angle in the experimental group containing silver sulfadiazine compared to the control group. In contrast, the experimental group showed a significant decrease in antibacterial activity compared to the control group in terms of OD value. Analysis of CFU confirmed a significant decrease in colonies in the experimental group compared to the control group. Conclusions: Denture base resin containing silver sulfadiazine, an inorganic antibacterial agent, exhibited enhanced antibacterial activity without physical changes. In conclusion, the use of denture base resin containing inorganic antibacterial agents may be expected in the future.

The Improvement of surface activity and Emulsification Activity by Transformation of Lipase Gene in Klebsiella sp. KCL-1, Oil-Degrading Bacterium. (Lipase gene의 도입에 의한 유류분해세균 Klebsiella sp. KCL-1의 표면활성과 유화력 향상)

  • 정수열
    • Journal of Life Science
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    • v.14 no.5
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    • pp.834-839
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    • 2004
  • To improve and oil degrading activity, the lipase gene from Pseudomonase sp. was transformed into Klebsiella sp. KCL-l, an oil degrading bacterium. The selected trasformant was named as a KCL-1/pET-Lip. The surface tension of culture broth of KCL-1/pET-Lip was decreased to 33 dyne/cm from 55 dyne/cm using 4% (v/v) soybean oil as sole carbon source. The surface tension were 44 and 37.5 dyne/cm, to 2% (w/v) glucose and 4% (v/v) kerosene medium, respectively. The emulsification activity of the biosurfactant solution containing lipase of KCL-l/pET-Lip improved better than wild type KCL-l. The soybean oil was most efficient carbon source and substrate for surface activity and emulsification activity of KCL-1/pET-Lip. The expression of lipase was confirmed by SDS-PAGE.