• Journal of Korean Neurosurgical Society
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• v.65 no.1
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• pp.151-160
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• 2022

Continuous monitoring of intracranial pressure is a well established medical procedure. Still, little is known about long-term behavior of intracranial pressure in normal pressure hydrocephalus. The present study is designed to evaluate periodicity of intracranial pressure over long-time scales using intraventricular pressure monitoring in patients with normal pressure hydrocephalus. In addition, the circadian and diurnal patterns of blood pressure and body temperature in those patients are studied. Four patients, selected with "probable" normal pressure hydrocephalus, were monitored for several dozen hours. Intracranial pressure, blood pressure, and body temperature were recorded hourly. Autocorrelation functions were calculated and cross-correlation analysis were carried out to study all the time-series data. Autocorrelation results show that intracranial pressure, blood pressure, and body temperature values follow bimodal (positive and negative) curves over a day. The cross-correlation functions demonstrate causal relationships between intracranial pressure, blood pressure, and body temperature. The results show that long-term fluctuations in intracranial pressure exhibit cyclical patterns with periods of about 24 hours. Continuous intracranial pressure recording in "probable" normal pressure hydrocephalus patients reveals circadian fluctuations not related to the day and night cycle. These fluctuations are causally related to changes in blood pressure and body temperature. The present study reveals the complete loss of the diurnal blood pressure and body temperature rhythmicities in patients with "probable" normal pressure hydrocephalus.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.2
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• pp.87-92
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• 2009

Objects：The purpose of this study is to investigate the values of foot pressure of the stance phase during a gait cycle in hemiplegic gait. Method：42 patients who had a stroke and 42 healthy adults were evaluated by the RSscan system to analyze the stance phase of hemiplegic gait. The stance phase was evaluated as plantar foor pressure. Results：1) Foot plantar pressure of toe area, affected side and less affected side showed low distribution of the plantar foot pressure which is lower than plantar foot pressure of normal adults(p<0.05). 2) Foot plantar pressure of metatarsal area, showed significantly differences among hemiplesic patient's affected side and less affected side and distribution of plantar foot pressure of normal adults(p<0.05). 3) Foot plantar pressure of heel area, hemiplesic patients' affected side and less affected side showed lower distribution of the plantar foot pressure than plantar foot pressure of normal adults(p<0.05). Conclusion：The results of this study suggest that not only affected side but also less affected side in hemiplegic patients showed significantly differences in distribution of the plantar foot pressure of normal adults.

• Journal of Preventive Medicine and Public Health
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• v.32 no.4
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• pp.513-525
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• 1999

Objectives : High-normal blood pressure' is a factor influencing decision to initiate targeted intensive intervention strategy in westernized populations. JNC-VI offered the vigorous lifestyle modification for persons with 'high-normal blood pressure', who could be early detected. As a hypertension seems to be the result of multiple genetic factors operating in concert with associated environmental factors, it will be necessary to identify the high-normal blood pressure as a risk factor of hypertension for applying primary prevention strategy in Korean people. Methods : Although cohort study design might be adequate to recruit incidence cases, to keep time sequence of events, and to prevent information bias, nested case-control study was chosen for avoiding measurement errors because hypertension is a benign disease. Source population was the 'Seoul Cohort' participants and follow-up was done by using Korea Medical Insurance Corporation's database on the utilization of health services from 1 Jan93 to 30Jun97. Incidence cases were ascertained through the chart review, telephone contacts, and direct blood pressure measurements. Controls included the pairing of 4 individuals to each case on the basis of age. Results : As 75% of 247 incident cases had high-normal blood pressure, the crude odds ratio for hypertension was 2.04 (95% CI 1.47-2.83). Another statistically significant risk factors of hypertension were body mass index, dietary fiber, alcohol consumption, weekly activity and history of quitting smoking. The multivariate odds ratio of high-normal blood pressure adjusted for all risk factors was 1.84 (95% CI 1.31-2.56). Among high-normal blood pressure group, body mass index, weekly ethanol amounts, weekly physical activity, and dietary fiber except history of quitting smoking were still risk factors of hypertension. Conclusion : 'High-normal blood pressure' is a risk factor for hypertension in Korean middle-aged men, which represents that the vigorous lifestyle modification for persons with 'high-normal blood pressure' is need.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.173-180
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• 2007

The purpose of study was to compare plantar pressure during walking wearing the curved rear balance and normal shoes. Twelve university students(height: $177.2{\pm}4.6cm$, weight: $68.4{\pm}5.8kg$, age: $26.2{\pm}1.6yrs.$) who have no known musculoskeletal disorders were recruited as the subjects. Plantar foot pressures were evaluated using the Tekscan's pressure measurement systems while subjects walked upright position wearing the curved rear balance and normal shoes in random order at a speed of 1.3 m/s. The contacting dimension, the mean plantar pressure, and the peak plantar pressure were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions (p<.05). As a result, the curved rear balanced shoes showed as large as 38 up to 50 % of area at the rear side of feet than the normal shoes when measuring the contact area with upright position. In the distribution of average pressure, the curved rear balanced shoes displayed fairly low pressure compared to other normal shoes in general except for one area, which is M2, and especially, the measured pressures at the both rear (M1) and middle (M5) side of feet were low and statically significant. The contact area of the curved rear balanced shoes when walking was significantly larger at the rear (M1) and fore (M6, M7) side of feet. When considering pressure distribution at walking, low pressure was detected at the rear side of feet with the curved rear balanced shoes and at the fore side of feet for other normal shoes. The results showed that the contacting dimension of the curved rear balance shoes that acts between shoes and feet was higher than the corresponding value for the normal shoes in general; therefore it would reduce the pressure to the feet by allowing the each sole of the foot on the ground evenly.

• Korean Journal of Materials Research
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• v.33 no.8
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• pp.323-329
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• 2023

There are many types of foam molding methods. The most commonly used methods are the pressure foaming method, in which foam resin is mixed with a foaming agent at high temperature and high pressure, and the normal pressure foaming method, which foams at high temperature without pressure. The polymer resins used for foaming have different viscosities. For foaming under normal pressure, they need to be designed and analyzed for optimal foaming conditions, to obtain resins with low melt-viscosity or a narrow optimal viscosity range. This study investigated how changes in viscosity, molding temperature, and cross-link foaming conditions affected the characteristics of the molded foam, prepared by blending rubber polymer with biodegradable resin. The morphologies of cross sections and the cell structures of the normal pressure foam were investigated by SEM analysis. Properties were also studied according to cross-link/foaming conditions and torque. Also, the correlation between foaming characteristics was studied by analyzing tensile strength and elongation, which are mechanical properties of foaming composites.

• Annals of Rehabilitation Medicine
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• v.39 no.6
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• pp.897-904
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• 2015

Objective To investigate differences in plantar pressure distribution between a normal gait and unpredictable slip events to predict the initiation of the slipping process. Methods Eleven male participants were enrolled. Subjects walked onto a wooden tile, and two layers of oily vinyl sheet were placed on the expected spot of the 4th step to induce a slip. An insole pressure-measuring system was used to monitor plantar pressure distribution. This system measured plantar pressure in four regions (the toes, metatarsal head, arch, and heel) for three events: the step during normal gait; the recovered step, when the subject recovered from a slip; and the uncorrected, harmful slipped step. Four variables were analyzed: peak pressure (PP), contact time (CT), the pressure-time integral (PTI), and the instant of peak pressure (IPP). Results The plantar pressure pattern in the heel was unique, as compared with other parts of the sole. In the heel, PP, CT, and PTI values were high in slipped and recovered steps compared with normal steps. The IPP differed markedly among the three steps. The IPPs in the heel for the three events were, in descending order (from latest to earliest), slipped, recovered, and normal steps, whereas in the other regions the order was normal, recovered, and slipped steps. Finally, the metatarsal head-to-heel IPP ratios for the normal, recovered, and slipped steps were $6.1{\pm}2.9$, $3.1{\pm}3.0$, and $2.2{\pm}2.5$, respectively. Conclusion A distinctive plantar pressure pattern in the heel might be useful for early detection of a slip event to prevent slip-related injuries.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.138-144
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• 2011

Exaggerated blood pressure response during exercise has been found to increase the risk of future hypertension, left ventricular hypertrophy, cerebrovascular stroke, and CVD (cardiovascular disease) death. The aim of this study was to evaluate exercise capacity, cardiovascular factors in exaggerated blood pressure response during treadmill exercise testing. For research subjects, 72 subjects (normal blood response: 49 subjects, exaggerated blood response: 23 subjects) who received treadmill exercise test at J General Hospital were selected in this study. Exaggerated SBP (systolic blood pressure) response was defined as an SBP of 210 mmHg or greater during a maximal treadmill exercise test. The group with an exaggerated SBP response showed significantly higher values for RPP (rate pressure product) compared with the group with a normal SBP response. Subjects with METs (metabolic equivalents) had lower exaggerated SBP response than normal SBP response group. Subjects with recovery SBP had delayed exaggerated SBP response than normal SBP response group. Exaggerated SBP response to exercise is negative correlation with METs.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.6
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• pp.12-19
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• 2003

This paper presents the effect of boundary conditions in various failure pressure models published for the estimation of failure pressure. Furthermore, this approach is extended to the failure prediction with the aid of a failure probability model. The first order Taylor series expansion of the limit state function is used in order to estimate the probability of failure associated with each corrosion defect in buried pipelines for long exposure period with unit of years. A failure probability model based on the von-Mises failure criterion is adapted. The log-normal and standard normal probability functions for varying random variables are adapted. The effects of random variables such as defect depth, pipe diameter, defect length, fluid pressure, corrosion rate, material yield stress, material ultimate tensile strength and pipe thickness on the failure probability of the buried pipelines are systematically investigated for the corrosion pipeline by using an adapted failure probability model and varying failure pressure model.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.2
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• pp.239-243
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• 2013

PURPOSE: The purpose of present study was to investigate effects of obesity, blood pressure and life style on lipid indices and blood pressure in men of age 40s. METHODS: One hundred forty five subjects in men of age 40s were participated in this study. All participants were taken physical examination, lifestyle survey and laboratory test. According to examination, participants were divided into two group in four categories ; obesity and normal group, hypertension and normal group, smokers and non-smokers, and drinkers and non-drinkers. The low density lipoprotein cholesterol (LDL), high density lipoprotein cholesterol (HDL), total cholesterol (TC), triglyceride (TG), systolic blood pressure (SBP), diastolic blood pressure (DBP) were analyzed by independent t-test for comparison between two groups. RESULTS: The values of LDL, TC, SBP, DBP were higher and HDL was lower in obesity than in normal group (p<.05). The values of LDL, TC, SBP, DBP were higher in hypertension group than in normal group (p<.05). The values of TG was higher and HDL was lower in smokers than in non-smokers (p<.05). There's no significant differences between drinkers and non-drinkers (p>.05). CONCLUSION: It can be seen that obesity and blood pressure were more relative risk factors than smoking and alcohol indices in cardiovascular diseases.

• Speech Sciences
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• v.12 no.4
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• pp.203-213
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• 2005

This study was conducted to investigate the respiratory and aerodynamic function of adductor spasmodic dysphonia (ADSD) patients. Participants were (1) 18 females SD patients with non- Botulinum toxin injection (2) 14 females SD patients who had taken treatment of Botulinum toxin injection. (3) 14 age- and sex- matched normal female controls. Spirometer and phonatory function analyzer were used for respiratory muscle pressure (MIP: Maximum inspiratory pressure), MEP: Maximum expiratory pressure)& MPT(Maximum phonation time) and aerodynamic(F0:Fundamental frequency, intensity, MFR: Mean flow late, Psub: Subglottal pressure) measurement. The results were as follows: (1) Normal group was significantly higher in MIP, MEP, MPT than two SD groups (p < .05); (2) MPT was significantly lower in SD with non-Botulinum toxin injection group than SD with the treatment experience of Botulinum toxin injection (p < .05); (3) All aerodynamic parameters, F0, intensity, MFR, Psub, were not significantly different among three groups(p > .05).The reason of short MPT in ADSD may use lower respiratory pressure than normal group as strategy to decrease their tremulous voice quality. Moreover respiratory muscle pressure was lower than normal group regardless of botulinum toxin injection treatment.