• The Korean Journal of Physiology
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• v.2 no.2
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• pp.53-61
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• 1968

Maximal oxygen debt, lactate and excess lactate were measured in 13 men with low hematocrit ratio before and after maximal exercise. Maximal exercise run was performed on a treadmill and the duration of run was 2 minutes 45 seconds in each subject. Hematocrit ratio ranged between 35 and 47%, the mean being 39.8%. The following results were obtained. 1. Maximal oxygen debt expressed on basis of body weight increased as the hematocrit ratio decreased. The correlation coefficient between the two was r= -0.770. 2. The time necessary for decreasing to 50% of total maximal $O_2$ debt(half time) became longer as the hematocrit ratio decreased. In normal men the half time was about 4 minutes and at the longest it was 12 minutes in men with the lowest hematocrit ratio. 3. The lactate concentration reached its peak value after 3 minutes of recovery. Thereafter, the time course of decrease in lactate concentration coincided roughly with that of respiratory oxygen debt curve. To reach to the resting level, however, it took longer time than that of respiratory oxygen debt. 4. Resting concentrations of lactate was 1.28 mM/l, pyruvate 0.13 mM/l and L/P ratio was 9.8. Peak value of ${\Delta}L$ after exercise reached to the value of 10.4 mM/l and ${\Delta}L/P$ reached 26.0. Peak excess lactate after exercise was 6.34 mM/l. 5. The part of oxygen debt accounted for by the oxygen equivalent of excess lactate was only 38.4%. A better relationship between lactate and oxygen debt was observed and the part of oxygen debt accounted for by the oxygen equivalent of lactate was 63.3%. 6. Peak value of lactate after maximal exercise increased as the hematocrit ratio decreased. 7. Respiratory oxygen debt of 100 ml/kg was accounted for by lactate more than 60% and only 30% was by excess lactate. 8. Excess lactate was not a good index of respiratory oxygen debt.

• Genomics & Informatics
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• v.19 no.2
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• pp.15.1-15.7
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• 2021

The direction of evolution can estimate based on the variation among nonsynonymous to synonymous substitution. The simulative study investigated the nucleotide sequence of closely related strains of respiratory syndrome viruses, codon-by-codon with maximum likelihood analysis, z selection, and the divergence time. The simulated results, dN/dS > 1 signify that an entire substitution model tends towards the hypothesis's positive evolution. The effect of transition/transversion proportion, Z-test of selection, and the evolution associated with these respiratory syndromes, are also analyzed. Z-test of selection for neutral and positive evolution indicates lower to positive values of dN-dS (0.012, 0.019) due to multiple substitutions in a short span. Modified Nei-Gojobori (P) statistical technique results also favor multiple substitutions with the transition/transversion rate from 1 to 7. The divergence time analysis also supports the result of dN/dS and imparts substantiating proof of evolution. Results conclude that a positive evolution model, higher dN-dS, and transition/transversion ratio significantly analyzes the evolution trend of severe acute respiratory syndrome coronavirus 2, severe acute respiratory syndrome coronavirus, and Middle East respiratory syndrome coronavirus.

• The Journal of Korean Physical Therapy
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• v.25 no.6
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• pp.374-378
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• 2013

Purpose: Human body have biological rhythmic pattern in a day, which is affected by internal and external environmental factors. We investigated whether respiratory function was fluctuated according to the influence of time-of-day (around at 9 am, 1 pm, and 6 pm) in health subjects, using pulmonary function test (PFT). Methods: Eighteen healthy volunteers (8 men, mean ages; $22.4{\pm}1.6$, mean heights; $166.61{\pm}9.60$, mean weight; $59.3{\pm}10.3$) were recruited. Pulmonary function test (PFT) was measured at three time points in day, around 9 am, 1 pm, and 6 pm in calm research room with condition of under 55dB noise level, using a spirometer (Vmax 229, SensorMecis, USA). Forced vital capacity (FVC), forced expiratory volume at one second (FEV1), FVC/FEV1, and peak expiratory flow (PEF) were acquired. Results: In comparison of raw value of PFT among three time points, subjects showed generally better respiratory function at 9 am, than at other points, although no significance was found. In comparison of distribution of ranking for respiratory function in each individual, only PEF showed significant difference. In general, distributional ratio of subjects who showed best performance of respiratory function in a day was high. Conclusion: These findings showed that circadian rhythm by diurnal pattern was not detected on respiratory function throughout all day. But, best performance on respiratory function was observed mostly in the morning, although statistical significance did not exist.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.11 no.1
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• pp.146-156
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• 2007

1. The effect of variations in inspiration and expiration times on heart rate variability was studied in 78 healthy subjects (mean age $24.35{\pm}1.92$ years; 47 male) between regulated respiration group and normal respiration group as the control group. 2. The control group followed normal respiration pattern, whereas the regulated group followed three types of respiration pattern. The first pattern was long respiration(E/I ratio 1.6:1), the second pattern was short inspiration followed by long expiration (SILE), and the last pattern was long inspiration followed by short expiration(LISE). The average expiration/inspiration time ratios of SILE and LISE were 1.0 and 3.4, respectively. The respiration rate in the regulated group was approximately 10 cycles/min. 3. Respiration rate and tidal volume are respiratory variables known to modulate RSA. The results of the present study indicate that RSA can also be modulated by a third respiratory variable, the expiration/inspiratory time ratio. In this study, LF, HF, RSA, VLF is increased the most in LISE group compared to the other groups. HF and RSA increased significantly in the long respiration rate and SILE groups. However LF and VLF, which reflects the sympathetic tones, did not increase as much as the LISE group.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.11
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• pp.5527-5545
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• 2019

Through-wall ultra-wide band (UWB) radar has been considered as one of the preferred and non-contact technologies for the targets detection owing to the better time resolution and stronger penetration. The high time resolution is a result of a larger of bandwidth of the employed UWB pulses from the radar system, which is a useful tool to separate multiple targets in complex environment. The article emphasised on human subject localization and detection. Human subject usually can be detected via extracting the weak respiratory signals of human subjects remotely. Meanwhile, the range between the detection object and radar is also acquired from the 2D range-frequency matrix. However, it is a challenging task to extract human respiratory signals owing to the low signal to clutter ratio. To improve the feasibility of human respiratory signals detection, a new method is developed via analysing the standard deviation based kurtosis of the collected pulses, which are modulated by human respiratory movements in slow time. The range between radar and the detection target is estimated using joint time-frequency analysis (JTFA) of the analysed characteristics, which provides a novel preliminary signature for life detection. The breathing rates are obtained using the proposed accumulation method in time and frequency domain, respectively. The proposed method is validated and proved numerically and experimentally.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.316-321
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• 2022

Since 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly, infecting millions of people worldwide. On March 11, 2020, the World Health Organization declared coronavirus disease (COVID-19) a pandemic owing to the worldwide spread of SARS-CoV-2, which created an unprecedented burden on the global healthcare system. In this context, there are increasing concerns regarding co-infections with other respiratory viruses, such as the influenza virus. In this study, clinical data of patients infected with SARS-CoV-2 and other respiratory viruses were compared with patients infected with SARS-CoV-2 alone. The hematology and blood biochemistry results of 178 patients infected with SARS-CoV-2 , who were tested on admission, were retrospectively reviewed. In patients with SARS-CoV-2 and adenovirus co-infection, C-reactive protein levels were elevated on admission, whereas lactate dehydrogenase (LDH), prothrombin time, international normalized ratio, activated partial thromboplastin clotting time, and bilirubin values were all within the normal range. Moreover, patients with SARS-CoV-2 and human bocavirus co-infection had low LDH and high bilirubin levels on admission. These findings reveal the clinical features of respiratory virus and SARS-CoV-2 co-infections and support the development of appropriate approaches for treating patients with SARS-CoV-2 and other respiratory virus co-infections.

• The Journal of Korean Physical Therapy
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• v.16 no.4
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• pp.38-58
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• 2004

The regain of independent ambulatory ability is a important goal in the rehabilitation program of hemiplegic patient. Not only the function of lower extremity muscles, but also trunk muscles which stabilize extremities and pelvis, are important factors in normal gait. Therefor, it is necessary to develop an effective program which can improve muscle strength and symmetric activity of trunk muscles. The purpose of this study was to evaluate the influence of trunk muscle strengthening by forceful respiratory exercise on the gait asymmetry ratio in hemiplegic patient. 45 Hemiplegic patients due to stroke was randomized in 3 groups, forceful expiratory training(FET), forceful inspiratory training(FIT) and control group. In the experimental groups, ordinary physical therapy with forceful expiratory training and forceful inspiratory training for 20 minutes duration 3 times per week for 6 weeks were respectively performed. In the control group, only ordinary physical therapy was done. Before and after experiments, temporal-spatial gait parameters was measured in all patients. The data of 28 patients who carried out the whole experimental course were statistically analysed. The results of these experiment are as follows : 1. In comparison of difference of single support time asymmetry ratio among 3 groups, the FET group was significantly decreased than the control group (p<.05). 2. In comparison of difference of step length asymmetry ratio among 3 groups, the FIT group was significantly decreased than the control group (p<.05). Based on these results, it is concluded that the forced respiratory exercise program for 6 weeks can be improve the gait asymmetry ratio in hemiplegic patients. Therefore, the forced respiratory exercise is useful to improve the walking ability in hemiplegic patients. Since this study dealt only with the patients who could walk more than 3 meters in distance on floor independently, the further study for evaluating the influence of the forceful respiratory exercise on patients with acute stage stroke and also the development in various methods of use are expected.

• The Journal of Korean Physical Therapy
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• v.25 no.5
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• pp.311-315
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• 2013

Purpose: Forward head posture is a typical symptom in people who use computers for long periods of time. Respiration is a complex function involving co-operation of muscular, skeletal, and nervous systems. Abnormal posture can have a negative effect on respiratory function. The purpose of this study was to investigate the relationship between forward head posture and respiratory function in young adults. Methods: Forty-six healthy subjects participated in this study. Craniovertebral angle was measured for assessment of the forward head posture. The respiratory function of all subjects was evaluated by measuring forced vital capacity (FVC), forced expiratory volume at one second (FEV1), forced expiratory volume at one second/forced vital capacity (FEV1/FVC) ratio, and peak expiratory flow (PEF). The baseline of forward head posture was less than 49 degrees. Results: : Significant differences for predicted FVC and FEV1 were observed between the two groups, however, no statistically significant differences in FEV1/FVC ratio and PEF were observed between the two groups. Conclusion: Results of this study demonstrate that forward head posture has a negative effect on respiratory function in young adults.

• Tuberculosis and Respiratory Diseases
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• v.45 no.5
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• pp.1022-1030
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• 1998

Background : In volume-controlled ventilation, the use of inspiratory pause increases the inspiratory time and thus increases mean airway pressure and improves ventilation. But under the same I : E ratio, the effects of inspiratory pause on mean airway pressure and gas exchange are not certain. Moreover, the effects may be different according to the resistance of respiratory system. So we studied the effects of inspiratory pause on airway pressure and gas exchange under the same I : E ratio in volume-controlled ventilation. Methods: Airway pressure and arterial blood gases were evaluated in 12 patients under volume-controlled mechanical ventilation with and without inspiratory pause time 5%. The I : E ratio of 1 : 3, $FiO_2$, tidal volume, respiratory rate, and PEEP were kept constant. Results: $PaCO_2$ with inspiratory pause was lower than without inspiratory pause ($38.6{\pm}7.4$ mmHg vs. $41.0{\pm}7.7$ mmHg. p<0.01). P(A-a)$O_2$ was not different between ventilation with and without inspiratory pause $185.3{\pm}86.5$ mmHg vs. $184.9{\pm}84.9$ mmHg, p=0.766). Mean airway pressure with inspiratory pause was higher than without inspiratory pause ($9.7{\pm}4.0\;cmH_2O$ vs. $8.8{\pm}4.0\;cmH_2O$, p<0.01). The resistance of respiratory system inversely correlated with the pressure difference between plateau pressure with pause and peak inspiratory pressure without pause (r=-0.777, p<0.l), but positively correlated with the pressure difference between peak inspiratory pressure with pause and peak inspiratory pressure without pause (r=0.811, p<0.01). Thus the amount of increase in mean airway pressure with pause positively correlated with the resistance of respiratory system (r=0.681, p<0.05). However, the change of mean airway pressure did not correlated with the change of $PaCO_2$. Conclusion: In volume-controlled ventilation under the same I : E ratio of 1 : 3, inspiratory pause time of 5% increases mean airway pressure and improves ventilation. Although the higher resistance of respiratory system, the more increased mean airway pressure, the increase in mean airway pressure did not correlated with the change in $PaCO_2$.

• Physical Therapy Rehabilitation Science
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• v.10 no.3
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• pp.328-336
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• 2021

Objective: The purpose of this study was to investigate the effect of cervical range of motion training on the change in respiratory function growth rate at the group and individual level in stroke patients and stroke patients with tracheostomy tube. Design: A Multilevel Growth Model Methods: 8 general stroke patients and 6 stroke patients who had a tracheostomy tube inserted were subjected to cervical range of motion training 3 times a week for 4 weeks. Force vital capacity (FVC), Forced expiratory volume in the first second (FEV1), Forced expiration ratio (FEV1/FVC) and Manual assist peak cough flow (MPCF) were measured. Data were analyzed using descriptive statistics and multilevel analysis with HLM 8.0. Results: A significant difference was found in the respiratory function analysis growth rate of the entire group (p<0.05), and two groups were added to the research model. The linear growth rate of respiratory function in patients with general stroke increased with the exception of FEV1/FVC (p<0.05). Stroke patients with tracheostomy tube showed a decreasing pattern except for FVC. In particular, MPCF showed a significantly decreased result (p<0.05). Conclusions: This study found that the maintenance of improved respiratory function in stroke patients with tracheostomy tube decreased over time. However, cervical range of motion training is still a useful method for respiratory function in general stroke patients and stroke patients with tracheostomy tube.