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1.
Materials (Basel) ; 15(16)2022 Aug 10.
Article in English | MEDLINE | ID: mdl-36013630

ABSTRACT

Recently, the demand for spatial structures such as retractable dome roofs is increasing. The safety of dome roofs must be ensured even when they are open. Hence, studies analyzing the peak pressure coefficients of spherical dome roofs are actively being conducted. However, no peak pressure coefficients for the cladding design of elliptical retractable dome roofs have been proposed. Although several studies on elliptical open dome roofs that open from the edge to the center have been conducted, studies on those that open from the center to the edge are still insufficient. This study investigated the peak pressure coefficients of elliptical center-open dome roofs. For wind tunnel tests, a model was fabricated with an opening ratio of 30%. Under experimental conditions, five different wall height-to-span ratios (from 0.1 to 0.5) were used, with the roof rise-to-span ratio set at 0.1. Accordingly, the experimental values of the peak pressure coefficients of elliptical center-open dome roofs were compared with those of the closed dome roofs proposed in the Korean and Japanese wind load codes. Subsequently, their efficiency was verified. The findings were also compared with previous research outcomes. Based on the results, peak net pressure coefficients are proposed for cladding designs suitable for elliptical center-open dome roofs.

2.
Materials (Basel) ; 14(18)2021 Sep 13.
Article in English | MEDLINE | ID: mdl-34576493

ABSTRACT

Cladding for dome roofs is often made of membrane materials that are light and easy to install. Due to these characteristics, wind damage to dome roof cladding is very common. In particular, open or retractable dome roofs are prone to wind damage because of inadequacies in wind load calculations. In this study, the wind pressure characteristics of a dome with a central opening were investigated. Wind tunnel tests were performed, and the pressure distribution was investigated by analyzing external and internal pressure coefficients. Based on the experimental results, the peak net pressure coefficients for the cladding design of a dome roof with a central opening were proposed. For the external peak pressure coefficients, the values of leeward regions were similar despite height-span ratios and turbulence intensity values. For the internal peak pressure coefficients, negative pressure was dominant, and the coefficients were not significantly affected by changes in height-span ratio. This tendency locally increased the negative peak net pressure, in which the load acts in the upward direction, and relatively significantly increased the positive peak net pressure, in which the load acts in the downward direction.

3.
Materials (Basel) ; 13(24)2020 Dec 17.
Article in English | MEDLINE | ID: mdl-33348624

ABSTRACT

Studies on novel composite structures that can decrease floor height and improve constructional efficiency in order to increase spatial efficiency and lease revenue have been actively conducted. An innovative fire-proof, lightweight, absorbed, shallow, and hybrid (iFLASH) system was developed to solve construction site issues, such as improving constructability, reducing construction time, and attaining structural efficiency by reducing the weight of the building structure. This system can shorten the construction duration and decrease the floor height and structural weight, owing to features such as a low thickness and light weight. However, studies on the vibration characteristics of this new floor system have not been performed yet. As the general thickness of the iFLASH system ranges from 25 to 30 mm, it must have a sufficient floor vibration performance in order to be utilized. To evaluate the floor vibration performance of the iFLASH system, an experiment was performed in two buildings where the system was applied. This paper presents the results of the dynamic characteristics and serviceability testing as basic data for the vibration characteristics of the iFLASH system.

4.
Enzyme Microb Technol ; 131: 109340, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31615683

ABSTRACT

Diisononyl adipate is a plasticizer which has excellent property of low temperature resistance and is permitted in food contact materials. In this study, diisononyl adipate was synthesized from adipic acid and isononyl alcohol in a solvent-free system via immobilized lipase-catalyzed esterification. Liquid Eversa lipase from Thermomyces lanuginosus was immobilized on Lewatit VP OC 1600 carrier. The effects of temperature, substrate molar ratio, water activity of enzyme, vacuum, and enzyme loading on the reaction efficiency were investigated. Application of vacuum played a key role to achieve a 100% conversion. The optimal temperature, molar ratio (adipic acid to isononyl alcohol), water activity of enzyme, vacuum were 50 °C, 1:3, 0.75, 13.3 kPa, and 10% (based on weight of total substrate). Under these conditions, 100% conversion was achieved within 6 h.


Subject(s)
Adipates/metabolism , Eurotiales/enzymology , Lipase/metabolism , Enzymes, Immobilized/metabolism , Esterification , Fatty Alcohols/metabolism , Kinetics , Temperature , Vacuum
5.
Inorg Chem ; 55(11): 5398-404, 2016 Jun 06.
Article in English | MEDLINE | ID: mdl-27186802

ABSTRACT

The symmetry around a Dy ion is recognized to be a crucial parameter dictating magnetization relaxation dynamics. We prepared two similar square-antiprismatic complexes, [Dy(LOMe)2(H2O)2](PF6) (1) and Dy(LOMe)2(NO3) (2), where LOMe = [CpCo{P(O)(O(CH3))2}3], including either two neutral water molecules (1) or an anionic nitrate ligand (2). We demonstrated that in this case relaxation dynamics is dramatically affected by the introduction of a charged ligand, stabilizing the easy axis of magnetization along the nitrate direction. We also showed that the application of either a direct-current field or chemical dilution effectively stops quantum tunneling in the ground state of 2, thereby increasing the relaxation time by over 3 orders of magnitude at 3.5 K.

6.
Ann Rehabil Med ; 39(2): 285-93, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25932426

ABSTRACT

OBJECTIVE: To evaluate the effect of custom molded foot orthoses on children with growing pains of the lower extremities. METHODS: Children with growing pains were recruited during a clinic visit. None had any bony deformities, inflammatory joint disease or depression. Resting calcaneal stance position (RCSP) and calcaneal pitch angle were measured, and individual custom molded rigid foot orthoses were prescribed using the inverted orthotic technique to control for foot overpronation using the RCSP angle. Pain sites, degree and frequency of pain, and balance ability were evaluated using Balance Master computerized posturography prior to foot orthosis fitting, and 1 and 3 months later. RESULTS: Twenty children completed the study. Seventeen (75%) had overpronated feet. Significant improvements were noted after 1 and 3 months in pain degree and frequency, and after 3 months in balancing ability. CONCLUSION: The use of custom molded foot orthoses is a good method for treating children with multiple musculoskeletal pains in the leg.

7.
Phytochemistry ; 116: 170-179, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26021733

ABSTRACT

Lipid substances, such as fatty acids, γ-oryzanol, policosanols, and tocol (tocopherol+tocotrienol), were investigated in two rice cultivars, Ilpum and Dasan, during rice development. In both cultivars, the lipid extract level decreased steadily after it reached its maximum level. Additionally, there were differences in the fatty acid composition, depending on the rice developmental stage, between the two cultivars. The γ-oryzanol level increased during rice development, and there were differences in the composition of γ-oryzanol between the two cultivars. The levels of policosanols drastically decreased during the early stage of rice development in the two cultivars. The total tocol level showed a downward trend during rice development. The predominant tocol isomer in Ilpum was α-tocopherol during rice development. In Dasan, the predominant tocol isomer was α-tocopherol at the early stage, but γ-tocotrienol at the later stage. This study provided information on the levels and composition of lipid substances, such as fatty acids, γ-oryzanol, policosanols, and tocol during rice development.


Subject(s)
Oryza/chemistry , Chromans , Edible Grain/chemistry , Lipid Metabolism , Phenylpropionates , Seeds/chemistry , Tocopherols/analysis , Tocotrienols/analysis , Vitamin E/analogs & derivatives
8.
Ann Rehabil Med ; 39(6): 905-13, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26798604

ABSTRACT

OBJECTIVE: To evaluate the effect of custom-molded foot orthoses on foot pain and balance in children with symptomatic flexible flat foot 1 month and 3 months after fitting foot orthosis. METHOD: A total of 24 children over 6 years old with flexible flat feet and foot pain for at least 6 months were recruited for this study. Their resting calcaneal stance position and calcaneal pitch angle were measured. Individual custom-molded rigid foot orthoses were prescribed using inverted orthotic technique to control foot overpronation. Pain questionnaire was used to obtain pain sites, degree, and frequency. Balancing ability was determined using computerized posturography. These evaluations were performed prior to custom-molded foot orthoses, 1 month, and 3 months after fitting foot orthoses. RESULT: Of 24 children with symptomatic flexible flat feet recruited for this study, 20 completed the study. Significant (p<0.001) improvements in pain degree and frequency were noted after 1 and 3 months of custom-molded foot orthoses. In addition, significant (p<0.05) improvement in balancing ability was found after 3 months of custom-molded foot orthoses. CONCLUSION: Short-term use of custom-molded foot orthoses significantly improved foot pain and balancing ability in children with symptomatic flexible flat foot.

9.
J Korean Acad Nurs ; 44(5): 534-41, 2014 Oct.
Article in Korean | MEDLINE | ID: mdl-25381784

ABSTRACT

PURPOSE: This study was done to examine the actual state of influenza vaccination among pregnant women and factors affecting vaccination rate. METHODS: Data were collected using self-report questionnaires. Participants were pregnant women who participated in a prenatal education program at an acute care hospital in 2013. Data collected from 218 pregnant women were analyzed using the SPSS 18.0 Program. RESULTS: Only 48.6% of the pregnant women had received vaccination when the influenza was prevalent. Statistically significant factors affecting the influenza vaccination rate among pregnant women were vaccination experience in the previous year, knowledge and attitude about vaccination, and gestation period. CONCLUSION: Results indicate that the influenza vaccination rate among pregnant women is lower than that of elders, healthcare workers, and patients with chronic diseases, who have been considered to be the mandatory vaccination recipients. Therefore, it is necessary to develop programs and policies which provide information including safety of vaccines for pregnant women and to induce positive attitudes towards vaccination for these women, in order to ultimately improve the vaccination rate.


Subject(s)
Influenza Vaccines/immunology , Influenza, Human/prevention & control , Pregnant Women/psychology , Vaccination/statistics & numerical data , Adult , Female , Gestational Age , Health Knowledge, Attitudes, Practice , Humans , Pregnancy , Surveys and Questionnaires
10.
Korean J Audiol ; 18(2): 80-4, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25279230

ABSTRACT

A speech discrimination test is a test using a list of 25 phonetically balanced monosyllables. It is often overlooked but significant enough for pure tone audiometry. Many physicians have performed pure tone audiometry but without a speech discrimination test. A 73-year-old woman visited our clinic complaining of sudden bilateral hearing loss. Pure tone audiometry showed only bilateral high frequency loss. However, speech discrimination had decreased markedly. We decided to follow-up after 1 week of Ginexin-F® (ginkgo leaf extract) and Nafril® (nafronyl oxalate). She felt a gait disturbance within 2 days. Magnetic resonance imaging revealed a left thalamic hemorrhage. After a 1 month hospitalization, the hematoma subsided, and speech discrimination recovered 3 months later. Acute hearing loss due to thalamic hemorrhage that recovered has never been reported. We report the first case of retrocochlear hearing loss that occurred with a thalamic hemorrhage in a patient who recovered.

11.
Inorg Chem ; 53(19): 10437-42, 2014 Oct 06.
Article in English | MEDLINE | ID: mdl-25248141

ABSTRACT

Two trimetallic coordination complexes were prepared by self-assembly of [W(CN)8](3-) and the Mn(III) Schiff base followed by the addition of a Zn(II) or Fe(II) cationic unit. The octacyanotungstate connects neighboring Mn(III) centers to form a one-dimensional chain. The anionic chain requires cationic units of Zn(II) or Fe(II) to maintain charge balance in the structure. The Zn-containing complex shows ferrimagnetic behavior originating from the antiparallel alignment of W(V) and Mn(III) spins within the chain, which leads to slow magnetic relaxation at low temperatures. For the Fe(II)-containing compound, Fe(II) moieties are integrated into the ferrimagnetic chains, altering their spin states depending on the temperature. It appears that the coexistence of high- and low-spin states in the low temperature regime is responsible for the slower and faster relaxations of the magnetization.

12.
Inorg Chem ; 53(15): 7936-40, 2014 Aug 04.
Article in English | MEDLINE | ID: mdl-25036537

ABSTRACT

The two one-dimensional chain compounds [Mn(L1)(N3)]·H2O (1·H2O; H2L1 = 2,2'-((1E,1'E)-ethane-1,2-diylbis(azan-1-yl-1-ylidene))bis(phenylmethan-1-yl-1-ylidene)diphenol) and [Mn(L2)(N3)] (2; H2L2 = 2,2'-((1E,1'E)-2,2-dimethylpropane-1,3-diyl)bis(azan-1-yl-1-ylidene)-bis(phenylmethan-1-yl-1-ylidene)diphenol) bridged by single end-to-end azides were prepared via a self-assembly process. Each Mn(III) ion exhibits a characteristic Jahn-Teller elongation along the chain direction. For both compounds, antiferromagnetic interactions between Mn(III) spins within a chain are transmitted through the azide ligands, together with the apparent occurrence of spin canting at low temperatures. Remarkably, the coupling constants (J) for 1 and 2 exceed those reported for end-to-end azide-linked Mn(III) systems. A systematic magnetostructural relationship based on the torsion angle is established in terms of the torsion angle Mn-N(ax)···N(ax)-Mn (ax = axial) for the first time.

13.
Dalton Trans ; 43(19): 6994-7, 2014 May 21.
Article in English | MEDLINE | ID: mdl-24705865

ABSTRACT

Dehydration of the three-dimensional Cu(II)-Mn(III) coordination network undergoes a dramatic magnetic phase transformation from a paramagnetic state to a long-range magnetic ordered phase with glassy behavior. The gas adsorption behavior and re-entrant spin glass character are uniquely apparent in the dehydrated sample.


Subject(s)
Coordination Complexes/chemistry , Copper/chemistry , Magnetics , Manganese/chemistry , Organic Chemicals/chemistry , Dehydration , Ethylenediamines/chemistry , Porosity , Temperature
14.
Clin Exp Otorhinolaryngol ; 7(1): 63-5, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24587884

ABSTRACT

Relapsing polychondritis (RP) is an uncommon systemic disease that is characterized by episodic and progressive inflammation of the cartilaginous structures, which can be very debilitating and in some instances life-threatening. The pathogenic pathways of RP are largely unknown. However, several hypothesis have been suggested. We had an interesting case of aggravation of RP due to the infection. Graft cartilage on the nasal tip was affected by RP also. This case can give a clue of revealing the pathogenesis of RP. We introduce a case with a review of the literature.

15.
J Oleo Sci ; 63(1): 47-53, 2014.
Article in English | MEDLINE | ID: mdl-24371195

ABSTRACT

Rice bran oil (RBO) is a good source of several commercially important bioactive phytochemicals, such as tocols (i.e. tocopherols and tocotrienols) and ferulic esters of sterols (i.e. γ-oryzanol). The aims of the present study were to examine the effects of different pressure and temperature combinations on the fractional extraction of RBO using supercritical carbon dioxide (SC-CO2) and to assess the levels of tocols homologues and γ-oryzanol components in the resulting oil fractions. Fractional extraction of rice bran oil was performed using SC-CO2 at either 27.6 or 41.4 MPa and either 40 or 60°C. The effects of the four different pressure and temperature combinations on the levels of seven tocols homologues (α-, ß-, γ- and δ-tocopherol and α-, γ- and δ-tocotrienol) and the four major components of γ-oryzanol in the resulting oil fractions were investigated. Superior extraction efficiency was obtained using the higher pressure of 41.4 MPa. The tocols (particularly α-tocopherol and α-tocotrienol) were recovered early in the extraction process, while the γ-oryzanol compounds were obtained in the later stages. With regard to SC-CO2 extraction, tocols are more soluble than γ-oryzanol components, α-tocopherol is the most soluble of the tocols and the four γ-oryzanol components all have similar solubilities. Valuable data on solubilities of tocols homologues in SC-CO2 were provided from present study.


Subject(s)
Carbon Dioxide , Chemical Fractionation/methods , Phenylpropionates/analysis , Plant Oils/chemistry , Tocopherols/analysis , Tocotrienols/analysis , Phenylpropionates/isolation & purification , Pressure , Rice Bran Oil , Solubility , Temperature , Tocopherols/isolation & purification , Tocotrienols/isolation & purification
16.
Int J Cardiovasc Imaging ; 29 Suppl 2: 119-26, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24113897

ABSTRACT

The fat-rich anterior mediastinum could be a sensitive window for monitoring minute changes in vascularity induced by systemic vasculitis. To evaluate this hypothesis, an analysis of anterior mediastinal fat in patients with Behçet's disease and a control group was conducted. This study included 43 patients diagnosed with Behçet's disease within the last 11 years who underwent CT scan; 55 patients were selected as a control population. Mediastinal fat was classified according to CT morphology. Comparison of serum inflammatory markers was performed for evaluation of disease activity according to morphologic types, and average Hounsfield unit of the anterior mediastinum was measured. Significantly higher mean CT attenuation was observed in the Behçet's disease group, compared with the control group (-48.5 ± 33.5 vs. -67.7 ± 18.7, respectively, P < 0.05). Mediastinal fat types were classified as follows: pure fatty tissue (2 vs. 31 % [Behçet's disease vs. control group]), diffuse soft tissue infiltration (16 vs. 29 %), tubular structures (21 vs. 4 %), mixed infiltration with tubular structures (42 vs. 15 %), and evident thymic tissue (19 vs. 22 %). The value for mean mediastinal attenuation was significantly higher in the group with a high level of C-reactive protein than in the normal level group. The mean CT attenuation of anterior mediastinal fat is significantly higher in the Behçet's disease group, compared with the normal group. Although pathologic confirmation is needed, the cause is postulated to be either inflammatory neovascularization or minimal thymic hyperplasia induced by Behçet's disease.


Subject(s)
Adipose Tissue/diagnostic imaging , Behcet Syndrome/diagnostic imaging , Multidetector Computed Tomography , Adipose Tissue/immunology , Adult , Aged , Aged, 80 and over , Behcet Syndrome/blood , Behcet Syndrome/immunology , Biomarkers/blood , C-Reactive Protein/analysis , Cross-Sectional Studies , Female , Humans , Inflammation Mediators/blood , Male , Mediastinum , Middle Aged , Multidetector Computed Tomography/instrumentation , Neovascularization, Pathologic , Phantoms, Imaging , Retrospective Studies , Thymus Hyperplasia/diagnostic imaging
17.
Inorg Chem ; 52(15): 8677-84, 2013 Aug 05.
Article in English | MEDLINE | ID: mdl-23855908

ABSTRACT

Five one-dimensional bimetallic W(V)Mn(III) complexes 1-5, consisting of [W(CN)6(bpy)](-) anions and [Mn(Schiff base)](+) cations, were prepared. The central coordination geometry around each W atom is determined as a distorted dodecahedron (DD) for 1 and 2, and a distorted square antiprism (SAPR) for 3-5. Magnetic analyses demonstrate that compounds 1, 4, and 5 exhibit antiferromagnetic interactions between magnetic centers, which are different from the ferromagnetic couplings in 2 and 3. For the distorted DD geometry, the Mn-N(ax) (ax = axial) bond length increases when moving from 1 to 2, with the Mn-N(ax)-C(ax) angle remaining constant. The elongation of the bond length is responsible for the reduction in orbital overlap and consequent ferromagnetic coupling in 2. In comparison, for 3-5 with the distorted SAPR geometry, given that the Mn-N(ax) bond lengths are similar across all the samples, the increase in the Mn-N(ax)-C(ax) angles accounts for the enhanced magnetic strength. Notably, a correlation between structure and magnetic exchange coupling is established for the first time in W(V)Mn(III) bimetallic systems based on the [W(CN)6(bpy)](-) precursor.


Subject(s)
Magnetic Phenomena , Manganese/chemistry , Nitriles/chemistry , Organometallic Compounds/chemistry , Tungsten/chemistry , Models, Molecular , Molecular Conformation , Organometallic Compounds/chemical synthesis
18.
J Food Sci ; 77(2): C267-71, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22309126

ABSTRACT

Pinolenic acid (PLA) concentrate in fatty acid ethyl ester (FAEE) was efficiently produced from pine nut oil via lipase-catalyzed ethanolysis using a recirculating packed bed reactor (RPBR). The effects of reaction temperature, molar ratio, and residence time on the concentration of PLA were explored. Novozym 435 lipase from Candida antarctica showed less selectivity toward PLA esterified at the sn-3 position when temperature was increased from 45 to 55 °C. For the trials of molar ratio between 1: 50 and 1: 100 (pine nut oil to ethanol), there were no significant differences in the yield of PLA. Residence time of substrate in a RPBR affected significantly the PLA content as well as the yield of PLA. Optimal temperature, molar ratio (pine nut oil to ethanol), and residence time for production of PLA concentrate via lipase-catalyzed ethanolysis in a RPBR were 45 °C, 1: 50, and 3 min, respectively. Under these conditions, the maximal PLA content (36.1 mol%) in the concentrate was obtained during the initial 10 min of reaction.


Subject(s)
Lipase/metabolism , Nuts/chemistry , Pinus , Plant Oils/chemistry , Bioreactors , Candida/enzymology , Catalysis , Enzymes, Immobilized , Fungal Proteins , Lipase/analysis , Temperature
19.
Inorg Chem ; 50(21): 10777-85, 2011 Nov 07.
Article in English | MEDLINE | ID: mdl-21978029

ABSTRACT

Three one-dimensional coordination polymers [Mn(L)(N(3))](n) [L = L1 (1), L2 (2), L3 (3); L1H(2) = N,N'-bis(5-chlorosalicylideneiminato)-1,3-diaminopentane, L2H(2) = N,N'-bis(5-bromosalicylideneiminato)-1,3-diaminopentane, L3H(2) = N,N'-bis(5-bromosalicylideneiminato)-1,3-diamino-2-dimethylpropane] bridged by end-to-end azides were prepared. The crystal systems differ according to the Schiff bases used. Each Mn atom adopts a typical Jahn-Teller distortion. The helicity of the chains occurs in a racemic manner only for 2. No noncovalent forces are relevant in 2, while π-π contacts are visible in 1 and 3. Magnetic measurements show the presence of apparent spin canting. Complexes 1 and 3 exhibit a field-induced metamagnetic transition from an antiferromagnetic state to a weak ferromagnetic phase, whereas 2 embraces a field-induced two-step magnetic phase transition. The critical temperature is observed at 38 K for 2, which is relatively higher than those for 1 (11 K) and 3 (10 K). The pronounced long-range order may contribute from intrachain exchange couplings and through-space dipolar interactions between adjacent chains.

20.
Inorg Chem ; 50(22): 11306-8, 2011 Nov 21.
Article in English | MEDLINE | ID: mdl-22013958

ABSTRACT

A 5d-3d bimetallic compound was prepared by self-assembling [W(CN)(8)](3-) and the Mn(III) Schiff bases. This neutral complex consists of cyanide-linked W(V)Mn(III) anionic chains and isolated Mn(III) Schiff base cations. We demonstrate that two types of relaxation processes are involved in the system; the low-T dynamics may come from magnetic domain dynamics and the high-T relaxation stems from the anionic chain, revealing single-chain magnet character.


Subject(s)
Cyanides/chemistry , Magnets/chemistry , Manganese/chemistry , Tungsten/chemistry , Models, Molecular , Molecular Conformation , Schiff Bases/chemistry
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