• Korean Membrane Journal
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• 제5권1호
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• pp.68-74
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• 2003

Methane steam reforming (MSR) reaction for hydrogen production was studied in a membrane reactor (MR) using two tubular membranes, one Pd-based and one of porous alumina. A higher methane conversion than the thermodynamic equilibrium for a traditional reactor (TR) was achieved using MRs. The experimental temperature range was 350-500$^{\circ}C$; no sweep-gas was employed during reaction tests to avoid its back-permeation through the membrane and the steam/methane molar feed ratio (m) varied in the range 3.5-5.9. The best results (the difference between the MR conversion and the thermodynamic equilibrium was of about 7%) were achieved with the alumina membrane, working with the highest steam/methane ratio and at 450$^{\circ}C$. Silica membranes prepared at KRICT laboratories were characterized with permeation tests on single gases (N$_2$, H$_2$ and CH$_4$). These membranes are suited for H$_2$ separation at high temperature.

• Advances in concrete construction
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• 제7권2호
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• pp.97-105
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• 2019

In this paper, the workability and static stability were evaluated using a proposed test method. Workability and static stability represent a key property of self-compacting concrete (SCC) in fresh state. A number of standardized test methods were developed to assess these properties. However, no accelerated test method reliably predicts both workability and static stability of SCC. In the present work, a modified K-slump test method was developed to evaluate workability and static stability of SCC. In order to take implicit mixture variations of SCC constituents that can affect fresh SCC properties, a central composite design was adopted to highlight the effect of gravel to sand ratio (G/S), gravel 3/8 to gravel 8/15 ratio (G1/G2), water to cement ratio (W/C), marble powder to cement ratio (MP/C) and superplasticizer content (SP) on workability measured with slump and flow time (T50) tests and static stability measured with sieve stability test (Pi), segregation test index (SSI), Penetration test (Pd) and the proposed K-slump test (Km). The obtained results show that G/S ratio close to 1 and G1/G2 ratio close to 60% can be considered as optimal values to achieve a good workability while ensuring a sufficient static stability of SCC. Acceptable relationships were obtained between Slump flow, Pi, Pd and Km. Results show that the proposed K-slump test allow to assess both workability and static stability of fresh SCC mixtures.

• 한방안이비인후피부과학회지
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• 제22권3호
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• pp.95-107
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• 2009

Objective : The purpose of this study is to search for more effective administraion route of herbal medicine. Methods : Pharmacokinetic issues with the methods in experimental papers, which deal with finding the effectiveness of two or more administration routes of herbal medicine, searched from KERIS, KSI, KISTI and KTKP, have been analyzed by, first, categorizing the papers and comparing the validity of administration routes. Results and Conclusions : 1. Upon comparing in total of 24 papers on the basis of each administration route, per oral(PO)-herbal acupuncture(HA) was most superior in terms of number in that there were 13 cases and PO-per rectal(PR) was next superior in that there were 5 cases. PO-per dermal(PD)-inhalation therapy(IT), PO-IT and PO-PR-HA had 3, 2 and 1 cases respectively. 2. Out of the total 24 papers which compares different administration routes, 16 of them were pharmacokinetically appropriate, whereas, the remaining 8 were pharmacokinetically inappropriate. 3. Comparisons were made between PO-HA, PO-PR, PO-IT, PO-PD-IT and PO-PR-HA routes. However, none of them was not particularly effective regardless of the administered medicine or target organ. 4. No route was particularly effective against a particular drug target as a result of comparing damaged liver, asthma, endometriosis and anti-inflammation. 5. In the case of Injinhotang in medicine comparison, HA tended to be more associated with hepatotoxicity over PO. However, Cordyceps Militaris Mycelia, Gagamsohaphyangwon and Hongdeungtang showed no prominent effective administration route.

• 대한치과보철학회지
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• 제35권1호
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• pp.103-117
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• 1997

The purpose of this experiment was to determind whether the gold electrodeposit on Pd-Ag and Ni-Cr alloys influences on the shear bond strength between veneering resin and silicoated metal surface. All the metal specimens were sandblasted with $250{\mu}m$ aluminum oxide and followed by silicoating and resin veneering. According to the metal surfaces to be veneered, experimental groups were divided into five. Group Prec : Gold alloy without gold coating Group Semi : Pd-Ag alloy without gold coating Group Base : Ni-Cr alloy without gold coating Group Semi-G : Pd-Ag alloy with gold coating Group Base-G : Ni-Cr alloy with gold coating All specimens were thermocycled 1,000 times at temperature of $5^{\circ}C$ to $55^{\circ}C$. The effects of gold electrodeposit on the shear bond strength between resin and metal interface were measured and fractured surface of the resin veneered metal was examined under the scaning electron microscope. The following results were obtained 1. The shear bond strength between resin and metal was $64.51{\pm}11.11Kg/cm^2$ in Prec group, $62.77{\pm}11.23Kg/cm^2$ in Base group and $58.97{\pm}9.20Kg/cm^2$ in Semi Group. There was no significant difference among the groups. 2. The bond strength in groups Semi-G and Base-G decreased about 17%, compared to the nongold-electrodeposit groups(Semi, Base). 3. In groups of non electrodeposit(Prec, Semi, Base), fracture occurred at the interface between alloy and resin, while fracture interface was observed between gold coating and resin in group Semi-G, and between metal substrate and gold coating in group Base-G respectively.

• Journal of Acupuncture Research
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• 제39권3호
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• pp.182-189
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• 2022

To evaluate the effectiveness of electroacupuncture treatment for primary dysmenorrhea (PD), a literature review of a randomized controlled trials (RCTs) was performed where electroacupuncture was used as a treatment intervention in patients diagnosed with PD. Relevant clinical studies (N = 226) were retrieved from multiple databases according to the study inclusion/exclusion criteria, and interventions and outcomes were analyzed. As a result of the review, there were 6 RCTs which met the criteria. In all 4 studies that measured pain indicators (visual analog scales), electroacupuncture showed significantly positive changes. In addition, positive changes were observed in most indicators (MMDQ, PGF2a, PGE2, 6-keto PGF1, TXB2, clinical efficacy score, uterine arterial blood flow parameters, and blood viscosity). 2 studies showed that electroacupuncture had a stronger therapeutic effect than NSAIDs. No major side effects were reported. Electroacupuncture may be an effective and safe treatment for PD however, further RCTs are required.

• 대한치과보철학회지
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• 제25권1호
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• pp.95-118
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• 1987

This study was undertaken to observe the elemental transition of Interface depending on different pretreatment methods, the number of filings, the kinds of porcelain powders and the various alloys in ceramo-metal restoration. The materials used in this study were Pors-on $4^{(R)}$ and Ceramco porcelain powder to compare the differences depending on the pretreatement methods and the number of firings. Ceramco porcelain powder and Vita porcelain powder were used to compare the differences of elemental transition depending on the porcelain powders. The $Parasil^{(R)},\;PGV^{(R)}$ and Pors-on $4^{(R)}$ as Pd-Ag alloy were used to compare the difference of elemental transition depending on the various alloys. The pretreatment methods were : no treatment, treatment under vacuum and air, treatment with 50 % hydrofluoric acid and double heat tretament. The number of firings were 3, 5 and 7 repeated firings All specimens were observed by SEM and concentration of elements were analyzed quantitatively with EPMA The results of this study were obtained as follows : 1. In the groups of air-treatment, concentration of Sn were the highest and widest. A high concentration of In were in the groups of vacuum and air treatment. 2. There were no significant differences in concentration of Sn between the group of vacuum, 5 minutes hydrofluoric acid and double heat treatment. (p>0.05) 3. As the period of time of hydrofluoric acid treatment increased, not only were the trace elements reduced but the main components such as Pd and Ag were also reduced. 4. Concentration of Sn and In increased and diffused with repeated firings but 5 repeated and 7 repeated firings groups had no significant differences. (p>0.05) 5. Sn were more concentrated in the group of Ceramco porcelaion powder than Vita porcelain powder. 6. The higher concentration of trace elements in the alloy, the more increasing concentration of Sn and In in the interface.

• Toxicological Research
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• 제17권2호
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• pp.115-121
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• 2001

Some of endocrine disruptors with sexual hormone-like effects have been increasingly reported to be immunotoxic in many species in recent several years. Phthalate esters have possible effects on the endocrine system. Prenatal exposure to di(n-butyl) phthalate (DBP) has been reported to impair the androgen-dependent development of the male reproductive tract in rat. Therefore, the immunomodulatory effect of DBP was investigated in the developing immune system of fetal and neonatal Sprague-Dawley rats. Timed-bred pregnant SD rats were given to the doses of 0, 250, 500, and 750 mg DBP/kg$\cdot$ body weight /day by gavage once a day from gestational day (GD) 5 to 18. On GD19 or GD22/postnatal day one (PD1), the dams were euthanized, and the changes in organ weights and thymus phenotypes were examined for their offsprings. At 750 mg DBP/kg$\cdot$b.w./day in maternal exposure group, GD19 fetuses showed decreases in body weight. The spleen/body weight ratios were reduced in GD 19 fetuses from the dams exposed to 500 and 750 mg DBP/kg$\cdot$b.w./day. There were no significant changes in thymus and spleen cellularities though these cellularities showed a tendency to decrease in a dose dependent way. In the DBP-exsposed GD22/PD1 offsprings, the body weights, the relative organ weights and the cellularities did not exhibit alteration. Additionally, the percentages of CD3$^{+}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) and CD3$^{-}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) thymocyte subsets were not changed in any DBP-treated group. The proliferative responses of splenic T cells to Con A and B cells to LPS were decreased in all DBP-exposed GD22/PD1 offsprings.

• Journal of Periodontal and Implant Science
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• 제36권1호
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• pp.211-221
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• 2006

The aim of present study was to evaluate the influence of periodontal status of adjacent tooth and loading time to the prevalence of red complex of implant sulcus. In 97 patients, partially edentulous subjects with endosseous root-form implants were selected. All subjects were medically healthy and had not taken systemic antibiotics and professional plaque control 3 months before sampling. The number was as follows: clinically healthy implants:161, clinically unhealthy implants:22, clinically healthy adjacent teeth:73, clinically unhealthy adjacent teeth:38. All teeth and implants of each patient were examined probing depth(PD), modified sulcus bleeding index(mSBI), and modified plaque index(mPI), and samples of subgingival plaque were obtained at each site with sterile curet or fine paper points, then the plaque transferred to PBS. Obtained samples were examined for the presence of P. gingivalis, T. forsythensis, and T. denticola by the polymerase chain reaction (PCR). The relationship among clinical parameters and the colonizations by the 3 bacterial species from adjacent teeth and implants region were analyzed by student t-test (p<0.05). The results of this study were as follows: 1. mPI and mSBI of implant increased with increasing of same indices of adjacent tooth(p=0.03,0.001), but not in the PD . 2. The mPI, mBI, PD of implants was higher when red complex exist. 3. The prevalence of red complex was higher when the periodontal condition is unhealthy. 4. The prevalence of red complex of implants has no significant relation to the probing depth of adjacent tooth. 5. Prevalence of P. gingivalis, T. forsythensis of implants increased with loading time. (p=0.02,0.018) These results shows the importance of oral hygiene and supportive periodontal therapy.

• 구강회복응용과학지
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• 제16권2호
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• pp.113-122
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• 2000

The reinforced composte resin as the esthetic operative material continuously has been studied because the porcelain fused metal prosthesis is widely used for its excellent esthetics, rigidity and marginal integrity, but it has low fracture resistance against the tensile strength and stress, attrition of the opposite teeth. The reinforced composite resin is well adapt with the dental alloy but it is low the shear bond strength with the dental alloy vs the porcelain fused metal prosthesis, and then has been studied continuously. The purpose of the study was to examine how metal was the higher shear bond strength among the dental alloy was used to the reinforced composite resin and to find the effect that the particle size of sandblasting influenced the shear bond strength. We built up the reinforced composite resin with 4 mm in diameter, 3 mm in height on circular alloy with 5 mm in diameter, 2 mm in height. Type II gold, type IV gold, and Ag-Pd alloy was used as alloys and $50{\mu}m$, $110{\mu}m$, $250{\mu}m$ of the particle size was sandblasted at each alloy in bonding between alloy and resin. We made 90 secimens of 10 per each group and we measured the shear bond strength using the Instron($M100EC^{(R)}$, Mecmesin Co., England). The obtained results were as follows : 1. In comparison among each alloys, Ag-Pd alloy had the highest shear bond strength and the shear bond strength was decreased significantly in the sequence of the type II gold and type IV gold(P<0.001). 2. In comparison according to the size of sandblasting particle, (1) In Ag-Pd alloy, shear bond strength was decreased in the sequence of $110{\mu}m$, $250{\mu}m$, $50{\mu}m$ and there were significant difference in all the group. (P<0.05) (2) In type II gold, it was decreased in the sequence of $250{\mu}m$, $50{\mu}m$, $110{\mu}m$ and there were significant difference. (P<0.05) (3) In type IV gold, it was decreased in the sequence of $110{\mu}m$, $50{\mu}m$, $250{\mu}m$. There were significant difference between the group of $110{\mu}m$ and $50{\mu}m$, the group of $110{\mu}m$ and 250, but there were no significant difference in the group of $50{\mu}m$ and $250{\mu}m$. 3. The highest shear bond strength according to the size of sandblasting particle was $110{\mu}m$ in Ag-Pd alloy and type IV gold, $250{\mu}m$ in type II gold.

• The Journal of Korean Physical Therapy
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• 제31권2호
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• pp.122-128
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• 2019

Purpose: This study examined the effects of sagittal spinopelvic alignment on the clinical parameters, motor symptoms, and respiratory function in patients with mild to moderate Parkinson's disease (PD). Methods: This study was a prospective assessment of treated patients (n=28, Hoehn and Yahr (H&Y) stage 2-3) in a PD center. Twenty-eight subjects ($68.5{\pm}5.7yrs$) participated in this study. The clinical and demographic parameters, including age, sex, symptoms duration, treatment duration, and H&Y stage, were collected. Kinematic analysis was conducted in the upright standing posture with a motion capture system. A pulmonary function test (PFT) was performed in the sitting position using a spirometer. The motor symptoms were assessed on part III of the movement disorder society sponsored version of the unified Parkinson's disease rating scale (MDS-UPDRS). SPSS 18.0 was used to analyze the collected data. Results: The exceeding 12 degrees group of the lower trunk showed significantly higher on the clinical parameters than the below 12 degrees group. In addition, the exceeding 12 degrees group of the lower trunk showed a significantly lower forced expiratory volume at one second (FEV1) / forced vital capacity (FVC) (%) and 25-75% forced mid-expiratory flow (FEF) (L/s) than in the below group. On the other hand, there was no difference in the upper trunk and the cervical pelvis between the groups. Conclusion: These findings suggest that the sagittal balance in the lower trunk is related to the clinical parameters and respiratory function, but not the motor symptoms in patients with mild to moderate PD.