• 제목/요약/키워드: lowering effect

검색결과 1,177건 처리시간 0.044초

Comparison of Biomechanical Stress on Low Back(L5/S1) for One-hand and Two-hands Lowering Activity

  • Kim, Hong-Ki
    • 대한인간공학회지
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    • 제32권5호
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    • pp.413-420
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    • 2013
  • Objective: The objective of this study was to compare one-hand and two-hands lowering activity in terms of biomechanical stress for the range of lowering heights from knuckle height to 10cm above floor level. Background: Even though two-hands lifting/lowering activity of manual materials handling tasks are prevalent at the industrial site, many manual materials handling tasks which require the worker to perform one-hand lifting/lowering are also very common at the industrial site and forestry and farming. Method: Eight male subjects were asked to perform lowering tasks using both a one-handed as well as a two-handed lowering technique. Trunk muscle electromyographic activity was recorded while the subjects performed the lowering tasks. This information was used as input to an EMG-assisted free-dynamic biomechanical model that predicted spinal loading in three dimensions. Results: It was shown that for the left-hand lowering tasks, the values of moment, lateral shear force, A-P shear force, and compressive force were increased by the average 6%, as the workload was increased twice from 7.5kg to 15kg. For the right-hand lowering task, these were increased by the average 17%. For the two-hands lowering tasks, these were increased by the average 14%. Conclusion: Even though the effect of workload on the biomechanical stress for both one-hand and two-hands lowering tasks is not so significant for the workload less than 15kg, it can be claimed that the biomechanical stress for one-hand lowering is greater than for two-hands lowering tasks. Therefore, it can be concluded that asymmetrical lowering posture would give greater influence on the biomechanical stress than the workload effect for one-hand lowering activity. Application: The result of this study may be used to provide guidelines of recommended safe weights for tasks involved in one-hand lowering activity.

골반경사방향과 발잘바기법이 물건 들어 올리기와 내리기 시 척추기립근의 활동전위에 마치는 영향 (The Effect of Pelvic Tilting and the Valsalva Maneuver on Electromyographic Activity of Erector Spinae During Squat Lifting and Lowering)

  • 노정석;이충휘;정보인;이영희
    • 한국전문물리치료학회지
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    • 제5권1호
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    • pp.30-43
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    • 1998
  • The purposes of this study were to examine the effect of two different pelvic alignments and the Valsalva maneuver on electromyographic (EMG) activity of the erector spinae during squat lifting and lowering, and to find an efficient method for squat lifting and lowering. Twenty hea1thy men in their twenties lifted and lowered loads using four different methods: 1) anterior pelvic tilt position with the Valsalva maneuver, 2) anterior pelvic tilt position without the Valsalva maneuver, 3) posterior pelvic tilt with the Valsalva maneuver, 4) posterior pelvic tilt without the Valsalva maneuver. The EMG activity of erector spinae was recorded during both lifting and lowering with each method. The EMG activity of each individual was normalized to EMG activity produced by muscle during maximal voluntary contraction. Two-way analysis of variance for repeated measures ($2{\times}2$) was used to analyze the effect of the two factors: 1) pelvic tilt position (anterior pelvic tilt, posterior pelvic tilt), 2) the Valsalva maneuver (with and without). Analysis was performed separately for the lifting and lowering. The results were as follows: 1) EMG activity of erector spinae was greater when the pelvis was tilted anteriorly than when the pelvis was tilted posteriorly during squat lifting and squat lowering. 2) There was no difference between EMG activity of erector spinae with the Valsalva maneuver and EMG activity of erector spinae without the Valsalva maneuver during squat lifting and squat lowering. These results suggest that the greater EMG activity of erector spinae with an anterior pelvic tilt position during squat lifting and squat lowering may ensure optimal muscular support for the spine while handling loads, but the Valsalva maneuver may have less effect on erector spinae.

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상엽의 혈당강하 활성 (Blood Glucose-Lowering Effects of Mori Folium)

  • 이주선;최명현;정성현
    • 약학회지
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    • 제39권4호
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    • pp.367-372
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    • 1995
  • Mori Folium(MF) methanol extract and its water soluble fraction showed significant blood glucose lowering effects alloxan-induced hyperglycemic mice. Their hypoglycemic activities seemed to nothing to do with the stimulation of insulin release or insulin-like action, according to our experiments. On the other hand, MF prevents the hyperglycemic responses from an oral load of starch and glucose in vivo. Since complex carbohydrates present in a diet must be degraded to monosaccharides by $\alpha$-glucohydrolase before being absorbed in the gastrointestinal tract, it is thought that blood glucose lowering effects of MF may be related to the inhibition of $\alpha$-glucohydrolase catalyzed enzymatic reaction. In addition, experiments that examined an effect of MF water soluble fraction on gastrointestinal movement showed no significant GI movement inhibitory effect. In conclusion, MF water soluble fraction may possess active component which is a potential candidate as an orally active agent for the treatment of diabetes mellitus.

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Impact of Energy Relaxation of Channel Electrons on Drain-Induced Barrier Lowering in Nano-Scale Si-Based MOSFETs

  • Mao, Ling-Feng
    • ETRI Journal
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    • 제39권2호
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    • pp.284-291
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    • 2017
  • Drain-induced barrier lowering (DIBL) is one of the main parameters employed to indicate the short-channel effect for nano metal-oxide semiconductor field-effect transistors (MOSFETs). We propose a new physical model of the DIBL effect under two-dimensional approximations based on the energy-conservation equation for channel electrons in FETs, which is different from the former field-penetration model. The DIBL is caused by lowering of the effective potential barrier height seen by the channel electrons because a lateral channel electric field results in an increase in the average kinetic energy of the channel electrons. The channel length, temperature, and doping concentration-dependent DIBL effects predicted by the proposed physical model agree well with the experimental data and simulation results reported in Nature and other journals.

유산균(Bifidobacterium bifidus)에 의해 발효된 발효유가 고지방식을 섭취한 흰쥐의 혈청과 간의 콜레스테롤 농도 저하에 미치는 효과 (The Effects of milk fermented by Bifidobacterium bifidus on lowering effect of Serum and Liver cholesterol in High Fat Diet Fed Rats)

  • 원향례;최석호
    • 한국지역사회생활과학회지
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    • 제12권1호
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    • pp.15-22
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    • 2001
  • This study was conducted to find out the effect of fermented milk on lowering of serum and liver cholesterol in high diet. Sprague-Dawley male rats of 200g initial average weight were assigned to four experimental group : (1) high fat diet + milk (2) high fat diet + bifidobacteria (3) high fat diet + microcapsulated bifidobacteria (4) high fat diet + fermented milk by bifidobacteria. Milk, bifidobacteria, microcapsulated bifidobacteria and fermented milk by bifidobacteria were given 2ml per day. According to the result, there was lowering effect of serum and liver total cholesterol in fermented milk feeding group, Serum LDL-cholesterol was also low tendency in fermented milk by bifidobacteria feeding group. Accordingly, it was confirmed that the material that caused hypocholesteremic effect was not the bifidobacteria itself in fermented milk but the metabolic material produced in the fermentation, and it inhibited cholesterol synthesis in liver.

Experimental study on effect of underground excavation distance on the behavior of retaining wall

  • Lee, Seok-Won
    • Geomechanics and Engineering
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    • 제17권5호
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    • pp.413-420
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    • 2019
  • The changes in earth pressure and ground settlement due to underground excavation near an existing retaining wall were studied experimentally according to the separation distance between the underground excavation and the retaining wall. In addition, this study attempted to experimentally prove that the arching phenomenon occurred during the construction of the underground space. A model tank having 120 cm in length, 160 cm in height, and 40 cm in width was manufactured to simulate underground excavation through the use of five separated base wall bodies. The variation of earth pressure on the retaining wall was measured according to the underground excavation phase through the use of 10 separated right wall bodies. The results showed that the earth pressure on the retaining wall was changed by the lowering of the first base bottom wall; however, the earth pressure was not changed significantly by the lowering of the third base bottom wall, since the third base wall had sufficient separation distance from the retaining wall. Lowering of the first base wall induced a decrease in the earth pressure in the lower part of the retaining wall; in contrast, lowering of the first base wall induced an increase in the earth pressure in the middle part of the retaining wall, proving the arching effect experimentally. It is necessary to consider the changes in earth pressure on the retaining wall in designing earth retaining structures for sections where the arching effect occurs.

PGC-1α 형질전환 생쥐에서 마늘 분말의 체지방 감소 효과 (The Body Fat-lowering Effect of Garlic Powder in Peroxisome Proliferator-activated Receptor γ Coactivator-1α (PGC-1α)-luciferase Transgenic Mice)

  • 이막순;김양하
    • 한국식품영양학회지
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    • 제30권5호
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    • pp.900-907
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    • 2017
  • This study was performed to investigate the body fat-lowering effect of garlic powder in peroxisome proliferator-activated receptor ${\gamma}$ coactivator-$1{\alpha}$(PGC-$1{\alpha}$)-luciferase transgenic mice (TG). In this study, we generated transgenic mice with a PGC-$1{\alpha}$ promoter (-970/+412 bp) containing luciferase as a reporter gene. Mice were fed a 45% high-fat diet for 8 weeks to induce obesity. Subsequently, mice were maintained on either a high-fat control diet (CON), or high-fat diets supplemented with 2% (GP2) or 5% (GP5) garlic powder for an additional 8 weeks. Dietary garlic powder reduced the body weight in the GP2 and GP5 groups, compared to the CON group. Furthermore, garlic supplementation significantly decreased the plasma levels of triglycerides, total cholesterol, and leptin in the GP5 group, compared to the CON group. Specifically, luciferase activity in liver, white adipose tissue (WAT), and brown adipose tissue (BAT) was increased by garlic supplementation in a dose-dependent manner. These results suggest that the body fat-lowering effect of garlic powder might be related to PGC-$1{\alpha}$ by the increase in luciferase activity in liver, WAT, and BAT. Furthermore, transgenic mice might be useful for evaluating the body fat-lowering effect of various health functional foods.

벨트를 이용한 가슴우리 고정이 누운자세에서 다리내리기 동안 복부 근육들의 근활성도에 미치는 영향 (Effect of Ribcage Stabilization Using a Belt on EMG Activity of the Abdominal Muscles During Double Leg Lowering in the Supine Position)

  • 원종혁
    • 대한통합의학회지
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    • 제5권2호
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    • pp.25-32
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    • 2017
  • Purpose : The purpose of this study was to determine the effect of ribcage stabilization using a belt in the supine position during double leg lowering (DLL) by investigating the electromyographic (EMG) activities of the abdominal muscles. Methods : Twenty-two subjects with lumbar extension syndrome were recruited. EMG activity was recorded from rectus abdominalis (RA) and internal oblique abdominalis (IO), external oblique abdominalis (EO) muscles while subjects performed three double leg lowering exercises: double leg lowering (DLL), double leg lowering with abdominal draw-in maneuver (DLL-ADIM), and double leg lowering with ribcage stabilization using a belt (DLL-belt). RA, IO, and EO EMG activity were analyzed via one-way repeated-measures analysis of variance (ANOVA). Bonferroni correction was performed where significant differences were identified (p<.017, .05/3). Results : RA, IO, and EO EMG activity differed significantly among the three exercises (p<.05). The use of post hoc pair-wise comparison with Bonferroni correction showed that RA muscle activity significantly differed among the three exercises (p<.017), and IO muscle activity in the DLL exercise was significantly decreased compared to the DLL-ADIM and DLL-belt exercises (p<.017). There was no significant difference between IO muscle activity for DLL-ADIM and DLL-belt exercises (p>.017). EO muscle activity in the DLL-belt exercise was significantly increased compared to both DLL and DLL-ADIM exercises (p<.017), but there was no significant difference between EO muscle activity for DLL and DLL-ADIM exercises (p>.017). Conclusion : DLL-belt is a more effective exercise for activating the abdominal muscles than DLL-ADIM exercise. Therefore, we recommend DLL-belt exercises for strengthening the abdominal muscles.

A New Two-Dimensional Model for the Drain-Induced Barrier Lowering of Fully Depleted Short-Channel SOI-MESFET's

  • Jit, S.;Pandey, Prashant;Pal, B.B.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제3권4호
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    • pp.217-222
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    • 2003
  • A new two-dimensional analytical model for the potential distribution and drain-induced barrier lowering (DIBL) effect of fully depleted short-channel Silicon-on-insulator (SOI)-MESFET's has been presented in this paper. The two dimensional potential distribution functions in the active layer of the device is approximated as a simple parabolic function and the two-dimensional Poisson's equation has been solved with suitable boundary conditions to obtain the bottom potential at the Si/oxide layer interface. It is observed that for the SOI-MESFET's, as the gate-length is decreased below a certain limit, the bottom potential is increased and thus the channel barrier between the drain and source is reduced. The similar effect may also be observed by increasing the drain-source voltage if the device is operated in the near threshold or sub-threshold region. This is an electrostatic effect known as the drain-induced barrier lowering (DIBL) in the short-gate SOI-MESFET's. The model has been verified by comparing the results with that of the simulated one obtained by solving the 2-D Poisson's equation numerically by using the pde toolbox of the widely used software MATLAB.

Combined Lowering Effects of Rosuvastatin and L. acidophilus on Cholesterol Levels in Rat

  • Wang, Lijun;Zhou, Baihua;Zhou, Xue;Wang, Yang;Wang, Hongwei;Jia, Shengying;Zhang, Zhipeng;Chu, Chao;Mu, Jianjun
    • Journal of Microbiology and Biotechnology
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    • 제29권3호
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    • pp.473-481
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    • 2019
  • Statins are a class of lipid-lowering drugs commonly used in the prevention of cardiovascular diseases. However, statin therapy presents many limitations, which have led to an increased interest in non-drug therapies, such as probiotics, to improve blood cholesterol levels. Indeed, probiotic strains such as Lactobacillus acidophilus have been found to improve blood lipid profiles, especially in reducing total cholesterol and LDL-C levels. In this study, we established a high-cholesterol rat model and studied the effect of Lactobacillus acidophilus administration alone or in combination with rosuvastatin. We were able to show that Lactobacillus exerts a cholesterol-lowering effect. Additionally, we observed that when administered together, rosuvastin and Lactobacillus exert a combined cholesterol-lowering effect. Altogether, our data advocate for the possibility of establishing probiotics as non-drug supplements for the treatment of hypercholesterolemia.