• Physical Therapy Rehabilitation Science
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• v.13 no.1
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• pp.53-70
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• 2024

Background: The conventional deadlift is a popular exercise for enhancing trunk, core, and lower extremity strength. However, its use in sports medicine is constrained by concerns of lumbar injuries, despite evidence supporting its safety and rehabilitative benefits. To optimize muscle activation using resistive bands in variable resistance therapy, we explored their feasibility in the deadlift. Design: Comparative experimental design Methods: Surface electromyography recorded muscle activity in the trunk and lower extremities during lifting, with normalization to the isometric Floor Lift using Maximal Voluntary Contraction. Kinematics were measured using inclinometer sensors to track hip and trunk sagittal plane angles. To prevent fatigue, each subject only used one of the three pairs of bands employed in the study. Results: Our study involved 45 healthy subjects (mean age: 30.4 ± 6.3 years) with similar baseline characteristics, except for years of lifting and strength-to-years-of-lifting ratio. Various resistance band groups exhibited significantly higher muscle activity than conventional deadlifts during different phases. The minimal resistance band group had notably higher muscle activity in the trunk, core, and lower extremity muscles, particularly in the end phase. The moderate resistance band group showed increased muscle activity in the mid-and end-phases. The maximum resistance band group demonstrated greater muscle activity in specific muscles during the early phase and overall higher activity in all trunk and lower extremity muscles in the mid and end phases of the deadlift (p<0.05). Conclusion: Our findings provide valuable insights into muscle activation with various resistance bands during deadlift exercise in clinical and gym settings. There appears to be a dose-response relationship between increased resistance bandwidth, external load, myoelectric activation, and range.

• Journal of Korean Society of Forest Science
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• v.79 no.2
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• pp.115-126
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• 1990

This study was performed to find differences in phototaxis response of the larva, adult emergence, sex ratio and gall formation rate of Thecodiplosis japonensis Uchida et Inouye between two areas, north and south. Larvae from these two areas, Hweng-sung in north and Moo-an in south, both considered to be the sities of severe outbreak of the insect recently, were collected from the floor and transported to the entomology larboratory, Won-Kwang University in Iri, then overwintered. These larvae were used for various experimental purposes on various dates. The following results were obtained. 1. The sizes of larvae reached 2.45 in length, 0.70 in width for north, and 2.50 in length, 0.72 in width for sourth. It seems that the differents were not significant. 2. It is known that Leaving gall of larvae to the ground for the hibernation usually occurs on rainy days. For the larvae dispersion, the phototaxis response of the larvae was hypothesized. To check this, the author manipulated some different illumination intensities adjusting the distance between the glass tube in which 100 larvae were contained and electric bulb. The glass tubes were blackened all but except a small portion. The phototaxis responses between two areas seemed to be different particularly at low light intensities, 45, 145 and 1000 lux, The larvae from north assembled to the clear portion of the glass tube were more than 30 out of 100, however less than 30 in south sample regardless of the time passage. In either cases, the saturation points came after about 8 to 10 hours. If temperature units were used, the phototaxis curve= after 1 hour illumination between two areas provided significant differences. 3. The adult emergence of south area was lagged 10 days later than that of north area. The accumulated effective day-degrees of temperature for adult emergence were $934^{\circ}C$ for north area and $1180^{\circ}C$ for south area. The emerging duration of north area appeared to be in late May through the early of July and the peak emergence occurred in middle June that was approximately 15days earlier than that of south area. The sex ratio of female to male, regardless of area, was approximately 3 : 1. 4. The rates of gall formation of the red pine(Pinus densiflora Siebold et Zuccarini), 6-year-old seedlings, were as low as 9.94% for north area and 8.87% for south area. Through the close observation, the author presumed that the population reduction was greatly affected during the prepupa stage by relative moisture content and predators, such as spiders and ants presented on the ground.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.289-296
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• 2002

A broiler experiment was conducted to investigate the effect of supplementing yeast culture (Saccharomyces cerevisiae, Pichia pastoris) on the growth performance, small intestinal microflora and immune response in broiler chickens. One thousand hatched broiler chickens(Ross$^{(R)}$) were assigned to 6 treatments: control (basal diet), CTC; chlorotetracycline 100ppm, YC-SC; yeast culture(Saccharomyces cerevisiae) 0.3%, YC-PP; yeast culture(Pichia pastoris) 0.3%, RPPC-0.1; refined Pichia pastoris culture 0.1%, RPPC-0.3; refined Pichia pastoris culture 0.3%. There were no significant differences in growth, feed intake, feed efficiency and mortality among the treatments. However, chickens fed diets with yeast cultures showed numerically higher weight gain than those fed the control diets. Supplementation of yeast cultures and CTC improved feed efficiency and decreased mortality compared to control. Nutrient digestibilities were not affected by the dietary treatments. Total number of Lactobacilli in small intestine was higher while that of Cl. perfringens was lower with yeast culture treatments than control. Small intestine E. coli population of RPPC-0.3 treatment was significantly lower than that of the control. The serum IgG concentration tended to be higher in broilers fed yeast cultures than those fed the control and CTC diet. In conclusion, the supplementation of yeast culture products showed, although not significant but, numerical advantages in productivity and profile of microbial flora and serum IgG compared to the control and CTC supplementation.

• Korean Journal of Poultry Science
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• v.33 no.2
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• pp.141-149
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• 2006

An experiment was conducted to investigate the effects of dietary acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) on the performance, nutrient metabolizability, small intestinal microflora, IgG level and leukocytes and erythrocytes in broiler chickens. Five hundred males and 500 females broiler chickens($Ross^(R)$) were divided into 20 pens of 50 chickens(25 birds in each sex). Five pens were assigned to each of four dietary treatments: control, diets containing antibiotics(Bacitracin methylene disalicilate), acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) dietary treatments. Birds were fed experimental diets ad libitum 5 wks. Weight gain, feed intake, and feed conversion rate were significantly affected by dietary treatment(P<0.05). Overall weight gain($0{\sim}5$ wks) of $Lactacid^(R)$ treatment was significantly lower than the others. Feed intake was highest(P<0.05) in the control followed by antibiotics, $Lactacid^(R)\;and\;Immunocin^(R)$ treatment. Feed conversion rate of $Immunocin^(R)$ treatment was lowest(P<0.05) followed by antibiotics, $Lactacid^(R)$ treatment and the control. Production indices of $Immunocin^(R)$ and antibiotics treatments were significantly higher than those of the control and $Lactacid^(R)$ treatment(P<0.05). $Immunocin^(R)$ treatment was the highest and antibiotics was lowest in serum IgG level. The number of leukocytes and stress index(neutrophil/lymphocytes) tended to be lower in $Immunocin^(R)$ treatment than others. There were no significant differences in erythrocytes among the treatments. The cfu of E. coli was significantly lower in $Immunocin^(R)$ and antibiotics treatments than $Lactacid^(R)$ treatment and the control. Metabolizability of crude protein was significantly lower in the control than $Lactacid^(R)\;and\;Immunocin^(R)$ treatment while that of NFE was significantly lower in $Immunocin^(R)\;than\;Lactacid^(R)$ and antibiotics treatments. It was concluded that essential oil product $Immunocin^(R)$ is as effective as antibiotics in improving feed conversion efficiency and production index while $Lactacid^(R)$ is not.

• The Korean Nurse
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• v.36 no.1
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• pp.108-117
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• 1997

This study was carried out to examine the standards for evaluation of laboratory facilities and equipment. These constitute the most important yet vulnerable area of our system of higher education among the six school evaluation categories provided by the Korean Council for University Education. To obtain data on the present situation of holdings and management of laboratory facilities and equipment at nursing schools in Korea, questionnaires were prepared by members of a special committee of the Korea Nursing Education Society on the basis of the Standards for University Laboratory Facilities and Equipment issued by the Ministry of Education. The questionnaires were sent to nursing schools across the nation by mail on October 4, 1995. 39 institutions completed and returned the questionnaires by mail by December 31 of the same year. The results of the analysis of the survey were as follows: 1. The Physical Environment of Laboratories According to the results of investigation of 14 nursing departments at four-year colleges, laboratories vary in size ranging from 24 to 274.91 pyeong ($1{\;}pyeong{\;}={\;}3.3m^2).$. The average number of students in a laboratory class was 46.93 at four-year colleges, while the number ranged from 40 to 240 in junior colleges. The average floor space of laboratories at junior colleges, however, was almost the same as those, of laboratories at four-year colleges. 2. The Actual State of Laboratory Facilities and Equipment Laboratory equipment possessed by nursing schools at colleges and universities showed a very wide distribution by type, but most of it does not meet government standards according to applicable regulations while some types of equipment are in excess supply. The same is true of junior colleges. where laboratory equipment should meet a different set of government standards specifically established for junior colleges. Closer investigation is called for with regard to those types of equipment which are in short supply in more than 80 percent of colleges and universities. As for the types of equipment in excess supply, investigation should be carried out to determine whether they are really needed in large quantities or should be installed. In many cases, it would appear that unnecessary equipment is procured, even if it is already obsolete, merely for the sake of holding a seemingly impressive armamentarium. 3. Basic Science Laboratory Equipment Among the 39 institutions, five four-year colleges were found to possess equipment for basic science. Only one type of essential equipment, tele-thermometers, and only two types of recommended equipment, rotators and dip chambers, were installed in sufficient numbers to meet the standards. All junior colleges failed to meet the standards in all of equipment categories. Overall, nursing schools at all of the various institutions were found to be below per in terms of laboratory equipment. 4. Required Equipment In response to the question concerning which type of equipment was most needed and not currently in possession, cardiopulmonary resuscitation (CPR) machines and electrocardiogram (ECG) monitors topped the list with four respondents each, followed by measuring equipment. 5. Management of Laboratory Equipment According to the survey, the professors in charge of clinical training and teaching assistants are responsible for management of the laboratory at nursing schools at all colleges and universities, whereas the chief of the general affairs section or chairman of the nursing department manages the laboratory at junior colleges. This suggests that the administrative systems are more or less different. According to the above results, laboratory training could be defined as a process by which nursing students pick up many of the nursing skills necessary to become fully qualified nurses. Laboratory training should therefore be carefully planned to provide students with high levels of hands-on experience so that they can effectively handle problems and emergencies in actual situations. All nursing students should therefore be thoroughly drilled and given as much on-the-job experience as possible. In this regard, there is clearly a need to update the equipment criteria as demanded by society's present situation rather than just filling laboratory equipment quotas according to the current criteria.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.271-280
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• 2020

This study compared soil CO₂ efflux rates after fertilization, in Pinus densiflora and Quercus variabilis stands. Compound fertilizers were applied to the forest floor in March 2016, following a one-year calibration period (from March 2015 to February 2016). In situ soil CO₂ efflux rates were measured every month during the two-year study periods, using an infrared gas analyzer with a closed chamber system. Mean annual soil CO₂ efflux rates were higher following fertilizer application in the P. densiflora and Q. variabilis stands (P. densiflora: 2.180 μmol m^-2 s^-1; Q. variabilis: 1.977 μmol m^-2 s^-1) as compared with the rates measured during the calibration period (P. densiflora: 1.620 μmol m^-2 s^-1; Q. variabilis: 1.557 μmol m^-2 s^-1). The mean annual soil CO₂ efflux rates in the unfertilized treatments of both stands were not significantly different between the two-year study periods. The Q₁₀ values of fertilized treatments in Q. variabilis stands were higher in the fertilization period (3.41) than in the calibration period (3.14), whereas the Q₁₀ values in P. densiflora stands did not change between the fertilization and calibration periods. The Q₁₀ values of unfertilized treatments in the Q. variabilis stands were lower during the 2016-2017 period (3.69), than in the 2015-2016 period (3.85), whereas the Q₁₀ values in P. densiflora stands were higher during the 2016-2017 period (3.65), than in the 2015-2016 period (3.15). These results indicate that the increase in soil CO₂ efflux rates in P. densiflora stands could be more sensitive to fertilization compared with the rates in Q. variabilis stands.

• Journal of the Society of Disaster Information
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• v.19 no.3
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• pp.634-643
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• 2023

Purpose: Underground common duct fires are steadily occurring, and the proportion of property damage is particularly large among property and human casualties caused by fires. Especially, cable fires that occur in common areas can spread vertically quickly and pose a great risk. This paper aims to scientifically analyze the nature of the fire by reproducing the fire through experiments. Method: To analyze the characteristics of cable fires in underground common duct, heat release rate and temperature changes were measured through Room-corner (ISO 9705) test, and the vertical and horizontal propagation of cable fires was quantitatively compared and analyzed. Result: The Room Corner Test (ISO 9705) was used to compare the temperature changes at each data logger point. The results showed that the time it took for the fire to reach the ignition temperature in the horizontal and vertical directions from the center point of the first-tier cable was 589 seconds and 536 seconds, respectively, which means that the vertical fire propagation is 53 seconds faster than the horizontal propagation. This proves that the vertical propagation of fire is relatively faster than the horizontal propagation. The horizontal propagation speed of the fire was also compared for each floor cable tray. The results showed that the third-tier cable propagated at 3.4 times the speed of the second-tier cable, and the second-tier cable propagated at 1.5 times the speed of the first-tier cable. This means that the higher the cable is located, the faster the fire spreads and the larger the fire becomes. Conclusion: This study identified the risks of cable fires and analyzed the risks of vertical fire propagation during cable fires based on the results of the Room Corner Test. Studies to prevent the spread of fire and fire response policies to prevent vertical fire propagation are required. The results of this study are expected to be used to assess the fire risk of common areas and other fires.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.52-61
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• 2013

This study was conducted to investigate the effects of pergola's shading on the thermal comfort index in the summer. The 3 type of pergolas($4m{\times}4m{\times}h2.7m$) which were screened overhead(I)/overhead west(II)/overhead west north(III) plane with reed blind for summer shading and winter wind break, were constructed on the 4th floor rooftop. Thereafter the meteorological variables(air temperature, humidity, radiation, and wind speed) of pergola I, III and rooftop were measured from 14 to 16 August 2013(1st experiment), those of pergola I, II and rooftop were measured from 26 to 28 August 2013(2nd experiment). The effects of pergola's shading on the radiation environment and mean radiant temperature($T_{mrt}$), standard effective temperature($SET^*$) were as follows. The maximum 1 h mean values of differences ${\Delta}$ of the sums of shortwave radiant flux densities absorbed by the human body (${\Delta}K_{abs,max}$) between pergola I, III and nearby sunny rooftop were $-119W/m^2$, $-158W/m^2$, those between pergola I, II and rooftop were $-145W/m^2$, $-159W/m^2$. The maximum 1 h mean values of differences ${\Delta}$ of the sums of long wave radiant flux densities absorbed by the human body (${\Delta}L_{abs,max}$) between pergola I, III and nearby sunny rooftop, were $-15W/m^2$, $-17W/m^2$, those between pergola I, II and nearby rooftop, were $-8W/m^2$, $-7W/m^2$. The response of the direction dependent long wave radiant flux densities $L_1$ on the pergola's shading turned out to be distinctly weaker as compared to shortwave radiant flux densities $K_1$. The pergola's shading leads to a lowering of $T_{mrt}$ and $SET^*$. The peak values of $T_{mrt}$ absorbed by the human body were decreased $16^{\circ}C$ and $21.4^{\circ}C$ under pergola I and III as compared to that of nearby rooftop in the 1st experiment. Those were decreased $18.8^{\circ}C$ and $20.8^{\circ}C$ under pergola I and II as compared to that of nearby rooftop in the 2nd experiment. The peak values of $SET^*$ absorbed by the human body were decreased $2.9^{\circ}C$ and $2.6^{\circ}C$ under pergola I and III as compared to that of nearby rooftop in the 1st experiment. Those were decreased $3.5^{\circ}C$ and $2.6^{\circ}C$ under pergola I and II as compared to that of nearby rooftop in the 2nd experiment. The relative $SET^*$ decrease in pergola II, III compared to nearby sunny rooftop $SET^*$ were lower than that in pergola I, revealing the influence of the wind speed. Therefore it is essential to design pergola to maximize wind speed and minimize solar radiation to achieve comfort in the hot summer. The $SET^*$ under pergola I, III were exceeded $28.7^{\circ}C$ and $30.4^{\circ}C$ which were the upper limit of thermal comfort and tolerable zone during all most daytimes in the 1st experiment(maximum air temperature $37.5^{\circ}C$). The $SET^*$ under pergola I was exceeded $28.7^{\circ}C$ which was the upper limit of thermal comfort zone at 13h, that under pergola II was exceeded $28.7^{\circ}C$ from 8h to 14h, meanwhile the $SET^*$ under pergola I, II were within thermal tolerable zone during most daytimes in the 2nd experiment(maximum air temperature $34.4^{\circ}C$). Therefore to ensure the thermal comfort of pergola for summer hottest days, pergola should be shaded with not only reed blind but also climbing and shade plants. $T_{mrt}$ and $SET^*$ were suitable index for the evaluation of pergola's shading effects and outdoors.