Search results for: Seokho Kang
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 319

Search results for: Seokho Kang

139 Immunomodulatory Effect of Deer Antler Extract

Authors: Kang-Hyun Leem, Myung-Gyou Kim, Hye Kyung Kim

Abstract:

Velvet antler (VA), the immature antlers of male deer, is traditionally used for thousands of years in Asian countries, such as Korea, China, Taiwan, and Mongolia. It has been considered to improve immune system and physical strength. The goal of this study was to investigate the immunomodulatory effect of deer antler velvet using in vitro system. In the first step, the effects of VA (70% ethanol extract) on the proliferation of splenocytes, bone marrow cell, and macrophages were determined. Next, the effect of VA on the production of nitric oxide and phagocytic activity in macrophage were measured. The results showed that VA treatment increased concanavalin-A stimulated splenocyte, bone marrow cells, and macrophage proliferation in a dose dependent manner. VA at 50 and 100 ug/mL concentrations significantly enhanced the concanavalin-A stimulated splenocyte proliferation by 8.8% and 18.5%, respectively. The proliferation of bone marrow cells, isolated from 5wk-old ICR mice, were increased by 25.2% and 46.5% by 50 and 100 ug/mL VA treatment. RAW 264.7 cell proliferation reached peak value at 50 ug/mL of VA treatment exhibiting 108% of the basal value. Nitric oxide production by RAW 264.7 macrophage cells was slightly reduced by VA treatment but was not statistically significant. Moreover, the phagocytic activity of macrophages was enhanced by VA treatment. These results indicate that VA is effective in immune system.

Keywords: deer antler, splenocyte, bone marrow cells, macrophage proliferation, phagocytosis

Procedia PDF Downloads 275
138 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy

Authors: Hyunki Kang, Hi Won Jeong

Abstract:

The gas turbine operates for a long period of time under harsh, cyclic conditions of high temperature and pressure, where high turbine inlet temperature (TIT) can range from 1273 to 1873K. Therefore, Ni-base superalloys such as IN738, IN939, Rene 45, Rene 71, Rene 80, Mar M 247, CM 247, and CMSX-4 with excellent mechanical properties and resistance to creep, corrosion and oxidation at high temperatures are indeed used. Among the alloying additions for these alloys, aluminum (Al) and titanium (Ti) form gamma prime and enhance the high-temperature properties. However, when crack-damaged high-temperature turbine components such as blade and vane are repaired by fusion welding, they cause cracks. For example, when arc welding is applied to certain superalloys that contain Al and Ti with more than 3 wt.% and T3.5 wt%, respectively, such as IN738, IN939, Rene 80, Mar M 247, and CM 247, aging cracks occur. Therefore, repair technologies using diffusion brazing, which has less heat input into the base material, are being developed. Analysis of microstructural evolution of the brazed joints with a base metal of IN 939 Ni-base superalloy using brazing different filler metals was also carried out using X-ray diffraction, OEM, SEM-EDS, and EPMA. Stress rupture and high-temperature tensile strength properties were also measured to analyze the effects of different brazing heat cycles. The boron amount in the diffusion-affected zone (DAZ) was decreased towards the base metal and the formation of borides at grain boundaries was detected through EPMA.

Keywords: gas turbine, diffusion brazing, superalloy, gas turbine repair

Procedia PDF Downloads 42
137 Multi-Dimensional Energy Resource Evaluation in Climate Change beyond the 21st Century

Authors: Hameed Alshammari

Abstract:

The decarbonisation of the energy sector beyond the 21ˢᵗ century is akin to establishing morally responsible mechanisms that can propagate sustainable livelihoods (Denina et al., 2021). It implies that Kuwait undertakes a re-evaluation of energy generation gaps so as to tap the potential to reduce overreliance on fossil fuel (Si et al., 2020) and align with global views on sustainable energy generation and consumption.(Herrero, Pineda, Villar, & Zambrano, 2020). Without the economic pressure to switch to alternative sources of energy, Kuwait requires a multi-dimensional analysis the energy policies andsources of energy other than fossil fuels (Alsaad, 2021).Currently, Kuwait has an energy system that is highly skewed towards fossil fuels (Alsaad, 2021); hence, the reliance on burning fossil fuels forms part of the core elements of the general inefficient energy systems that have negative consequences to global environmental and economic systems (Kang et al., 2020). This paper undertakes a detailed literature review on factors needed for the development of a framework for the multi-dimensional energy resource analysis in Kuwait. The framework aims aligning the current energy policies in Kuwait with the global decarbonisation drive, to promote sustainable energy strategies.

Keywords: decarbonisation, energy, fossil fuels, multi-dimensional analysis, sustainability

Procedia PDF Downloads 86
136 Mercaptopropionic Acid (MPA) Modifying Chitosan-Gold Nano Composite for γ-Aminobutyric Acid Analysis Using Raman Scattering

Authors: Bingjie Wang, Su-Yeon Kwon, Ik-Joong Kang

Abstract:

The goal of this experiment is to develop a sensor that can quickly check the concentration by using the nanoparticles made by chitosan and gold. Using chitosan nanoparticles crosslinking with sodium tripolyphosphate(TPP) is the first step to form the chitosan nanoparticles, which would be covered with the gold sequentially. The size of the fabricated product was around 100nm. Based on the method that the sulfur end of the MPA linked to gold can form the very strong S–Au bond, and the carboxyl group, the other end of the MPA, can easily absorb the GABA. As for the GABA, what is the primary inhibitory neurotransmitter in the mammalian central nervous system in the human body. It plays such significant role in reducing neuronal excitability pass through the nervous system. A Surface-enhanced Raman Scattering (SERS) as the principle for enhancing Raman scattering by molecules adsorbed on rough metal surfaces or by nanostructures is used to detect the concentration change of γ-Aminobutyric Acid (GABA). When the system is formed, it generated SERS, which made a clear difference in the intensity of Raman scattering within the range of GABA concentration. So it is obtained from the experiment that the calibration curve according to the GABA concentration relevant with the SERS scattering. In this study, DLS, SEM, FT-IR, UV, SERS were used to analyze the products to obtain the conclusion.

Keywords: mercaptopropionic acid, chitosan-gold nanoshell, γ-aminobutyric acid, surface-enhanced raman scattering

Procedia PDF Downloads 275
135 Issues in Implementing ISO 9002 from the Islamic Perspective (ISI 2020)

Authors: Ahmad Masduki Bin Selamat, Kang Chia Yang

Abstract:

The International Standard Organization (ISO) is an international consensus on good management practice. It is derived from the Greek word “isos” meaning equal. ISO is aimed to give organization guidelines on what bring quality management system that leads to continuous improvement. The need of quality product is essential these days, especially in the manufacturing and service sectors. The requirement to produce good product is demanded, hence the certification of ISO enables the company to gain the trust from the public. Due to this, organizations whether government or private sectors in Malaysia are going for the ISO certification. However recently there has been an introduction of Islamic standard known as Islamic Standard Institute 2020 (ISI 2020). The ISI standards emphasize more on values that should be in the employees’ mind. By possessing good values, employees will work only for the betterment of the company. Currently only the feelings of being paid for the job exist in the employees’ mind. The non-Malays like Chinese and others, which comprise 40% of the sample size, are not aware about the existence of any Islamic quality system. As for the Malay managers, they support the Islamic quality systems. For them such values are encouraged by religion. By imitating religion, Allah promises a better life in this world and hereafter. Even though ISI 2020 is still new but the majority of Malays would support the need of Islamic quality system. Our findings suggest that integration of these two-quality systems running parallel would bring a better result.

Keywords: International Standard Organization (ISO), Islamic standard, quality, ISI 2020

Procedia PDF Downloads 415
134 An Event-Related Potential Study of Individual Differences in Word Recognition: The Evidence from Morphological Knowledge of Sino-Korean Prefixes

Authors: Jinwon Kang, Seonghak Jo, Joohee Ahn, Junghye Choi, Sun-Young Lee

Abstract:

A morphological priming has proved its importance by showing that segmentation occurs in morphemes when visual words are recognized within a noticeably short time. Regarding Sino-Korean prefixes, this study conducted an experiment on visual masked priming tasks with 57 ms stimulus-onset asynchrony (SOA) to see how individual differences in the amount of morphological knowledge affect morphological priming. The relationship between the prime and target words were classified as morphological (e.g., 미개척 migaecheog [unexplored] – 미해결 mihaegyel [unresolved]), semantical (e.g., 친환경 chinhwangyeong [eco-friendly]) – 무공해 mugonghae [no-pollution]), and orthographical (e.g., 미용실 miyongsil [beauty shop] – 미확보 mihwagbo [uncertainty]) conditions. We then compared the priming by configuring irrelevant paired stimuli for each condition’s control group. As a result, in the behavioral data, we observed facilitatory priming from a group with high morphological knowledge only under the morphological condition. In contrast, a group with low morphological knowledge showed the priming only under the orthographic condition. In the event-related potential (ERP) data, the group with high morphological knowledge presented the N250 only under the morphological condition. The findings of this study imply that individual differences in morphological knowledge in Korean may have a significant influence on the segmental processing of Korean word recognition.

Keywords: ERP, individual differences, morphological priming, sino-Korean prefixes

Procedia PDF Downloads 217
133 Comparison of Phenolic and Urushiol Contents of Different Parts of Rhus verniciflua and Their Antimicrobial Activity

Authors: Jae Young Jang, Jong Hoon Ahn, Jae-Woong Lim, So Young Kang, Mi Kyeong Lee

Abstract:

Rhus verniciflua is commonly known as a lacquer tree in Korea. Stem barks of R. verniciflua have been used as an immunostimulator in traditional medicine. It contains phenolic compounds and is known for diverse biological activities such as antioxidant and antimicrobial activity. However, it also causes allergic dermatitis due to urushiols derivatives. For the development of active natural resources with less toxicity, the content of phenolic compounds and urushiols of different parts of R. verniciflua such as stem barks, lignum and leaves were quantitated by colorimetric assay and HPLC analysis. The urushiols content were the highest in stem barks, and followed by leaves. The lignum contained trace amount of urushiols. The phenolic contents, however, were the most abundant in lignum, and followed by leaves and stem barks. These results clear showed that the content of urushiols and phenolic differs depending on the parts of R. verniciflua. Antimicrobial activity of different parts of R. verniciflua against fish pathogenic bacteria was also investigated using Edwardsiella tarda. Lignum of R. verniciflua was the most effective in antimicrobial activity against E. tarda and phenolic constituents are suggested to be active constituents for activity. Taken together, phenolic compounds are responsible for antimicrobial activity of R. verniciflua. The lignum of R. verniciflua contains high content of phenolic compounds with less urushiols, which suggests efficient antimicrobial activity with less toxicity. Therefore, lignum of R. verniciflua are suggested as good sources for antimicrobial activity against fish bacterial diseases.

Keywords: different parts, phenolic compounds, Rhus verniciflua, urushiols

Procedia PDF Downloads 320
132 Phosphoinositide 3-Kinase-Dependent CREB Activation is Required for the Induction of Aromatase in Tamoxifen-Resistant Breast Cancer

Authors: Ji Hye Im, Nguyen T. T. Phuong, Keon Wook Kang

Abstract:

Estrogens are important for the development and growth of estrogen receptor (ER)-positive breast cancer, for which anti-estrogen therapy is one of the most effective treatments. However, its efficacy can be limited by either de novo or acquired resistance. Aromatase is a key enzyme for the biosynthesis of estrogens, and inhibition of this enzyme leads to profound hypoestrogenism. Here, we found that the basal expression and activity of aromatase were significantly increased in tamoxifen (TAM)-resistant human breast cancer (TAMR-MCF-7) cells compared to control MCF-7 cells. We further revealed that aromatase immunoreactivity in tumor tissues was increased in recurrence group after TAM therapy compared to non-recurrence group after TAM therapy. Phosphorylation of Akt, extracellular signal-regulated kinase (ERK), and p38 kinase were all increased in TAMR-MCF-7 cells. Inhibition of phosphoinositide 3-kinase (PI3K) suppressed the transactivation of the aromatase gene and its enzyme activity. Furthermore, we have also shown that PI3K/Akt-dependent cAMP-response element binding protein (CREB) activation was required for the enhanced expression of aromatase in TAMR-MCF-7 cells. Our findings suggest that aromatase expression is up-regulated in TAM-resistant breast cancer via PI3K/Akt-dependent CREB activation.

Keywords: TAMR-MCF-7, CREB, estrogen receptor, aromatase

Procedia PDF Downloads 413
131 A Study on the Effect of Rib Structure in Spoke-Type PMSM

Authors: Hyun-Soo Seol, In-Gun Kim, Hyun Seok Hong, Dong-Woo Kang, Ju Lee

Abstract:

Rotor of Spoke-Type PMSM is divided into permanent magnet and rotor core. Moreover, rotor core is composed of pole-piece, Bridge and rib. Piece between the permanent magnet N and S poles is pole-piece. Bridge and rib hold pole-piece. In the case of pole-piece and bridge, it is essential structure of Spoke-Type PMSM. However, Rib can be selected by the designer depending on the operating conditions and constraints. If rib is present in the rotor, rib which acts in the leak path generates a leakage flux. Although the leakage flux reduces the torque in low speed, it expands speed range in high speed. So, there is a relationship of trade off. Viewed from the standpoint of permanent magnet demagnetization, since the magnetic flux by the stator winding leaks to the rib, it is an advantage. In addition, rib affects the safety factor of the rotor. For application required high speed operation, since the securing the safety factor of the rotor is important, rib structure is advantageous. On the other hand, in the case of the application that does not require high speed operation, it is desirable to increase the output power by designing without rib. In this paper, Effects on rib structure is analyzed in detail and this paper provides designer with information about rotor design of spoke-type PMSM according to rib structure.

Keywords: spoke-Type PMSM, rotor shape, rib, operation range

Procedia PDF Downloads 430
130 Biodegradable Poly D,L-Lactide-Co-Glycolic Acid Microparticle Vaccine against Aeromonas hydrophila Infection

Authors: Saekil Yun, Sib Sankar Giri, Jin Woo Jun, Hyoun Joong Kim, Sang Guen Kim, Sang Wha Kim, Jung Woo Kang, Se Jin Han, Se Chang Park

Abstract:

In aquaculture, vaccination is important to control and prevent diseases. In the study, we utilized poly D,L-lactide-co-glycolic acid (PLGA) microparticles (MPs) for encapsulating formalin-killed Aeromonas hydrophila cells. To assess the innate and adaptive immune responses, carps and loaches were used for the experiments. Fish were divided into three groups (A, B, C). Total antigen of 0.1 ml vaccine was adjusted by 2 x 108 CFU and injected via intraperitoneal route. Group A was vaccinated with 0.1 ml of PLGA vaccine, group B was with 0.1 ml of FKC vaccine and group C was with 0.1 ml of sterile PBS. All three groups were challenged with A. hydrophila and challenge dose was lethal dose (LD50). Loaches and carp were then challenged with A. hydrophila at 12 and 20 weeks post vaccination (wpv), and 10 and 14 wpv, respectively, and relative survival rates were calculated. For both fish species, the curve of antibody titer over time was shallower in the PLGA group than the FKC group and the PLGA groups demonstrated higher survival rates at all time-points. In the groups of PLGA-MP, relative mRNA levels of IL-1β, TNF-α, lysozyme C and IgM were significantly upregulated than FKC treated groups. Biodegradable PLGA microparticle vaccine could induce longer immune responses than original FKC vaccines to protect from A. hydrophila infection.

Keywords: PLGA, microparticles, Aeromonas hydrophila, vaccine

Procedia PDF Downloads 272
129 Grid Based Traffic Vulnerability Model Using Betweenness Centrality for Urban Disaster Management Information

Authors: Okyu Kwon, Dongho Kang, Byungsik Kim, Seungkwon Jung

Abstract:

We propose a technique to measure the impact of loss of traffic function in a particular area to surrounding areas. The proposed method is applied to the city of Seoul, which is the capital of South Korea, with a population of about ten million. Based on the actual road network in Seoul, we construct an abstract road network between 1kmx1km grid cells. The link weight of the abstract road network is re-adjusted considering traffic volume measured at several survey points. On the modified abstract road network, we evaluate the traffic vulnerability by calculating a network measure of betweenness centrality (BC) for every single grid cells. This study analyzes traffic impacts caused by road dysfunction due to heavy rainfall in urban areas. We could see the change of the BC value in all other grid cells by calculating the BC value once again when the specific grid cell lost its traffic function, that is, when the node disappeared on the grid-based road network. The results show that it is appropriate to use the sum of the BC variation of other cells as the influence index of each lattice cell on traffic. This research was supported by a grant (2017-MOIS31-004) from Fundamental Technology Development Program for Extreme Disaster Response funded by Korean Ministry of Interior and Safety (MOIS).

Keywords: vulnerability, road network, beweenness centrality, heavy rainfall, road impact

Procedia PDF Downloads 95
128 Joint Modeling of Longitudinal and Time-To-Event Data with Latent Variable

Authors: Xinyuan Y. Song, Kai Kang

Abstract:

Joint models for analyzing longitudinal and survival data are widely used to investigate the relationship between a failure time process and time-variant predictors. A common assumption in conventional joint models in the survival analysis literature is that all predictors are observable. However, this assumption may not always be supported because unobservable traits, namely, latent variables, which are indirectly observable and should be measured through multiple observed variables, are commonly encountered in the medical, behavioral, and financial research settings. In this study, a joint modeling approach to deal with this feature is proposed. The proposed model comprises three parts. The first part is a dynamic factor analysis model for characterizing latent variables through multiple observed indicators over time. The second part is a random coefficient trajectory model for describing the individual trajectories of latent variables. The third part is a proportional hazard model for examining the effects of time-invariant predictors and the longitudinal trajectories of time-variant latent risk factors on hazards of interest. A Bayesian approach coupled with a Markov chain Monte Carlo algorithm to perform statistical inference. An application of the proposed joint model to a study on the Alzheimer's disease neuroimaging Initiative is presented.

Keywords: Bayesian analysis, joint model, longitudinal data, time-to-event data

Procedia PDF Downloads 145
127 Investigation of Fire Damaged Concrete Using Nonlinear Resonance Vibration Method

Authors: Kang-Gyu Park, Sun-Jong Park, Hong Jae Yim, Hyo-Gyung Kwak

Abstract:

This paper attempts to evaluate the effect of fire damage on concrete by using nonlinear resonance vibration method, one of the nonlinear nondestructive method. Concrete exhibits not only nonlinear stress-strain relation but also hysteresis and discrete memory effect which are contained in consolidated materials. Hysteretic materials typically show the linear resonance frequency shift. Also, the shift of resonance frequency is changed according to the degree of micro damage. The degree of the shift can be obtained through nonlinear resonance vibration method. Five exposure scenarios were considered in order to make different internal micro damage. Also, the effect of post-fire-curing on fire-damaged concrete was taken into account to conform the change in internal damage. Hysteretic non linearity parameter was obtained by amplitude-dependent resonance frequency shift after specific curing periods. In addition, splitting tensile strength was measured on each sample to characterize the variation of residual strength. Then, a correlation between the hysteretic non linearity parameter and residual strength was proposed from each test result.

Keywords: nonlinear resonance vibration method, non linearity parameter, splitting tensile strength, micro damage, post-fire-curing, fire damaged concrete

Procedia PDF Downloads 269
126 A Study on Human Musculoskeletal Model for Cycle Fitting: Comparison with EMG

Authors: Yoon- Ho Shin, Jin-Seung Choi, Dong-Won Kang, Jeong-Woo Seo, Joo-Hack Lee, Ju-Young Kim, Dae-Hyeok Kim, Seung-Tae Yang, Gye-Rae Tack

Abstract:

It is difficult to study the effect of various variables on cycle fitting through actual experiment. To overcome such difficulty, the forward dynamics of a musculoskeletal model was applied to cycle fitting in this study. The measured EMG data were compared with the muscle activities of the musculoskeletal model through forward dynamics. EMG data were measured from five cyclists who do not have musculoskeletal diseases during three minutes pedaling with a constant load (150 W) and cadence (90 RPM). The muscles used for the analysis were the Vastus Lateralis (VL), Tibialis Anterior (TA), Bicep Femoris (BF), and Gastrocnemius Medial (GM). Person’s correlation coefficients of the muscle activity patterns, the peak timing of the maximum muscle activities, and the total muscle activities were calculated and compared. BIKE3D model of AnyBody (Anybodytech, Denmark) was used for the musculoskeletal model simulation. The comparisons of the actual experiments with the simulation results showed significant correlations in the muscle activity patterns (VL: 0.789, TA: 0.503, BF: 0.468, GM: 0.670). The peak timings of the maximum muscle activities were distributed at particular phases. The total muscle activities were compared with the normalized muscle activities, and the comparison showed about 10% difference in the VL (+10%), TA (+9.7%), and BF (+10%), excluding the GM (+29.4%). Thus, it can be concluded that muscle activities of model & experiment showed similar results. The results of this study indicated that it was possible to apply the simulation of further improved musculoskeletal model to cycle fitting.

Keywords: musculoskeletal modeling, EMG, cycle fitting, simulation

Procedia PDF Downloads 569
125 Stenotrophomonas maltophilia: The Major Carbapenem Resistance Bacteria from Waste Water Treatment Plant of Pig Farm

Authors: Young-Ji Kim, Jin-Hyeong Park, Hong-Seok Kim, Jung-Whan Chon, Kwang-Yeop Kim, Dong-Hyeon Kim, Il-Byeong Kang, Da-Na Jeong, Jin-Hyeok Yim, Ho-Seok Jang, Kwang-Young Song, Kun-Ho Seo

Abstract:

Stenotrophomonas maltophilia is one of the emerging opportunistic pathogens, and also known to have extensive drug resistance intrinsically including carbepenems which is last resort for most serious infections. One possible way for S. maltophilia to infect human is via wastewater treatment plant (WWTP). In the period between October 2016 and February 2017, effluent samples of WWTP from 3 different pig farms were collected once a month and screened for isolation of S. maltophilia. Total 16 strains of S. maltophilia were isolated and, the antibiotic susceptibility phenotypes were determined by Vitek 2 system for 16 antibiotics, ampicillin (AMP), amoxicillin/clavulanic acid (AMC), piperacillin/tazobactam (TZP), cefazolin (CZ), cefoxitin (FOX), cefotaxime (CTX), ceftazidime (CAZ), cefepime (FEP), aztreonam (AZT), ertapenem (ETP), imipenem (IMP), amikacin (AK), gentamicin (GN), ciprofloxacin (CIP), tigecycline (TGC) and trimethoprim/sulfamethoxazole (SXT). All isolates showed high resistance to AMP (100%), CZ (100%), FOX (100%), CTX (100%), CAZ (100%), FEP (94%), AZT (100%), ETP (100%), IMP (100%), AK (100%), GN (100%) whereas were susceptible to CIP (0%), TGC (0%), SXT (6%). All strains harbored at least one of the antibiotic resistance determinant such as spgM, rmlA, and rpfF. Some isolates had similar MLST (multilocus sequence typing) types with clinical isolates, suggesting WWTP could have potential role in the transmission of S. maltophilia to aquatic environment and, possibly, to humans.

Keywords: Stenotrophomonas maltophilia, Carbapenem resistance, waste water treatment plant, pig farm

Procedia PDF Downloads 463
124 A Fundamental Study on the Anchor Performance of Non-Surface Treated Multi CFRP Tendons

Authors: Woo-tai Jung, Jong-sup Park, Jae-yoon Kang, Moon-seoung Keum

Abstract:

CFRP (Carbon Fiber Reinforced Polymer) is mainly used as reinforcing material for degraded structures owing to its advantages including its non-corrodibility, high strength, and lightweight properties. Recently, dedicated studies focused not only on its simple bonding but also on its tensioning. The tension necessary for prestressing requires the anchoring of multi-CFRP tendons with high capacity and the surface treatment of the CFRP tendons may also constitute an important issue according to the type of anchor. The wedge type, swage type or bonded type anchor can be used to anchor the CFRP tendon. The bonded type anchor presents the disadvantage to lengthen the length of the anchor due to the low bond strength of the CFRP tendon without surface treatment. This study intends to overcome this drawback through the application of a method enlarging the bond area at the end of the CFRP tendon. This method enlarges the bond area by splitting the end of the CFRP tendon along its length and can be applied when CFRP is produced by pultrusion. The application of this method shows that the mono-CFRP tendon and 3-multi CFRP tendon secured the anchor performance corresponding to the tensile performance of the CFRP tendon and that the 7-multi tendon secured anchor performance corresponding to 90% of the tensile strength due to the occurrence of buckling in the steel tube anchorage.

Keywords: carbon fiber reinforced polymer (CFRP), tendon, anchor, tensile property, bond strength

Procedia PDF Downloads 247
123 Determination of Marbofloxacin in Pig Plasma Using LC-MS/MS and Its Application to the Pharmacokinetic Studies

Authors: Jeong Woo Kang, MiYoung Baek, Ki-Suk Kim, Kwang-Jick Lee, ByungJae So

Abstract:

Introduction: A fast, easy and sensitive detection method was developed and validated by liquid chromatography tandem mass spectrometry for the determination of marbofloxacin in pig plasma which was further applied to study the pharmacokinetics of marbofloxacin. Materials and Methods: The plasma sample (500 μL) was mixed with 1.5 ml of 0.1% formic acid in MeCN to precipitate plasma proteins. After shaking for 20 min, The mixture was centrifuged at 5,000 × g for 30 min. It was dried under a nitrogen flow at 50℃. 500 μL aliquot of the sample was injected into the LC-MS/MS system. Chromatographic analysis was carried out mobile phase gradient consisting 0.1% formic acid in D.W. (A) and 0.1% formic acid in MeCN (B) with C18 reverse phase column. Mass spectrometry was performed using the positive ion mode and the selected ion monitoring (MRM). Results and Conclusions: The method validation was performed in the sample matrix. Good linearities (R2>0.999) were observed and the quantified average recoveries of marbofloxacin were 87 - 92% at level of 10 ng g-1 -100 ng g-1. The percent of coefficient of variation (CV) for the described method was less than 10 % over the range of concentrations studied. The limits of detection (LOD) and quantification (LOQ) were 2 and 5 ng g-1, respectively. This method has also been applied successfully to pharmacokinetic analysis of marbofloxacin after intravenous (IV), intramuscular (IM) and oral administration (PO). The mean peak plasma concentration (Cmax) was 2,597 ng g-1at 0.25 h, 2,587 ng g-1at 0.44 h and 2,355 ng g-1at 1.58 h for IV, IM and PO, respectively. The area under the plasma concentration-time curve (AUC0–t) was 24.8, 29.0 and 25.2 h μg/mL for IV, IM and PO, respectively. The elimination half-life (T1/2) was 8.6, 13.1 and 9.5 for IV, IM and PO, respectively. Bioavailability (F) of the marbofloxacin in pig was 117 and 101 % for IM and PO, respectively. Based on these result, marbofloxacin does not have any obstacles as therapeutics to develop the oral formulations such as tablets and capsules.

Keywords: marbofloxacin, LC-MS/MS, pharmacokinetics, chromatographic

Procedia PDF Downloads 549
122 Social Justice-Focused Mental Health Practice: An Integrative Model for Clinical Social Work

Authors: Hye-Kyung Kang

Abstract:

Social justice is a central principle of the social work profession and education. However, scholars have long questioned the profession’s commitment to putting social justice values into practice. Clinical social work has been particularly criticized for its lack of attention to social justice and for failing to address the concerns of the oppressed. One prominent criticism of clinical social work is that it often relies on individual intervention and fails to take on system-level changes or advocacy. This concern evokes the historical macro-micro tension of the social work profession where micro (e.g., mental health counseling) and macro (e.g., policy advocacy) practices are conceptualized as separate domains, creating a false binary for social workers. One contributor to this false binary seems to be that most clinical practice models do not prepare social work students and practitioners to make a clear link between clinical practice and social justice. This paper presents a model of clinical social work practice that clearly recognizes the essential and necessary connection between social justice, advocacy, and clinical practice throughout the clinical process: engagement, assessment, intervention, and evaluation. Contemporary relational theories, critical social work frameworks, and anti-oppressive practice approaches are integrated to build a clinical social work practice model that addresses the urgent need for mental health practice that not only helps and heals the person but also challenges societal oppressions and aims to change them. The application of the model is presented through case vignettes.

Keywords: social justice, clinical social work, clinical social work model, integrative model

Procedia PDF Downloads 87
121 New Variational Approach for Contrast Enhancement of Color Image

Authors: Wanhyun Cho, Seongchae Seo, Soonja Kang

Abstract:

In this work, we propose a variational technique for image contrast enhancement which utilizes global and local information around each pixel. The energy functional is defined by a weighted linear combination of three terms which are called on a local, a global contrast term and dispersion term. The first one is a local contrast term that can lead to improve the contrast of an input image by increasing the grey-level differences between each pixel and its neighboring to utilize contextual information around each pixel. The second one is global contrast term, which can lead to enhance a contrast of image by minimizing the difference between its empirical distribution function and a cumulative distribution function to make the probability distribution of pixel values becoming a symmetric distribution about median. The third one is a dispersion term that controls the departure between new pixel value and pixel value of original image while preserving original image characteristics as well as possible. Second, we derive the Euler-Lagrange equation for true image that can achieve the minimum of a proposed functional by using the fundamental lemma for the calculus of variations. And, we considered the procedure that this equation can be solved by using a gradient decent method, which is one of the dynamic approximation techniques. Finally, by conducting various experiments, we can demonstrate that the proposed method can enhance the contrast of colour images better than existing techniques.

Keywords: color image, contrast enhancement technique, variational approach, Euler-Lagrang equation, dynamic approximation method, EME measure

Procedia PDF Downloads 450
120 Impact of Traditional Male Circumcision Mishaps Towards Newly Initiated Men's Advancement in Education in South Africa

Authors: Thanduxolo Nomngcoyiya, Simon M. Kang’ethe

Abstract:

The aim of this article is to explore whether a relationship exists between traditional male circumcision mishaps and level of education in the Eastern Cape, South Africa, exemplified by an empirical case study. The study used qualitative paradigm; was exploratory in nature and used case study design that was descriptive and exploratory; and entailed interviewing twenty-eight (28) research participants comprising of eleven (11) newly initiated men and their families on one-on-one in-depth interviews, twelve (12) traditional nurses and community members in focus group discussions; and five (5) society key informants on key informant method. An interview guide served as a data collection instrument for focus group discussions, key informant method and in-depth interviews with unstructured open-ended questions. Findings indicated an array of traditional male circumcision (TMC) gaps, some of which were indicative of a relationship between the mishaps and level of education: the phenomenon of schooling became secondary in newly initiated men’s lives; TMC mishaps became a drawback towards the newly initiated men’s education progression; the newly initiated men are sacrificed at the altar of culture, and TMC mishaps ushered in socioeconomic setback to the newly initiated men. The study suggested that: TMC be developmental; TMC as a cultural endeavor be educational and human rights friendly; and the need to identify and integrate all other players with diverse specialties.

Keywords: culture, education for all, EFA, millennium development goals, traditional male circumcision

Procedia PDF Downloads 203
119 Bone Strengthening Effects of Deer Antler Extract

Authors: Hye Kyung Kim, Myung-Gyou Kim, Kang-Hyun Leem

Abstract:

It has been reported that deer antler extract has bone-strengthening activity and effectively used in bone diseases therapy. However, little is known about the cellular and molecular mechanism of this effect. The upper section, mid section, and base of the antler has been known to exhibit different biological properties. Present study investigated the effects of these three parts of deer antler extracts on bone formation and resorption. The effects of deer antler extracts (DH) on bone formation were determined by cell proliferation, alkaline phosphatase (ALP) activity, collagen synthesis, and mineralization in human osteoblastic MG-63 cells. The effect on bone resorption was determined by osteoclastogenesis from bone marrow-derived precursor cells driven by RANKL. Ethanol extracts of DH (50 ~ 100 µg/ml) dose-dependently increased cell proliferation, and upper part increased the cell proliferation by 118.4% while mid and base parts increased proliferation by 107.8% and 102.3%, respectively. ALP activity was significantly increased by upper part of the DH treatment. After enhancement of ALP activity, significant augmentation of collagen synthesis and calcification assessed by Sirus red and Alzarin red staining, respectively, was observed in upper part of the DH treatment. The effect of DH on bone resorption was not observed in all three parts of the DH. These results could provide a mechanistic explanation for the bone-strengthening effects of DH.

Keywords: alkaline phosphatase, collagen synthesis, deer antler, osteoblastic MG-63 cells

Procedia PDF Downloads 315
118 Production of Recombinant VP2 Protein of Canine Parvovirus Type 2c Using Baculovirus Expression System

Authors: Jae Young Song, In-Ohk Ouh, Seyeon Park, Byeong Sul Kang, Soo Dong Cho, In-Soo Cho

Abstract:

Canine parvovirus (CPV) is a major pathogen of diarrhea disease in dogs. CPV type 2 has three of antigenic variants such as 2a, 2b, and 2c. CPV constructs a small non-enveloped, icosahedral capsid that contains single-stranded DNA. It has capsids that two largely overlapping virion proteins (VP), VP1 (82 kDa), and VP2 (65 kDa). Baculoviruses are insect pathogens that regulate insect populations in nature and are being successfully used to control insect pests. The proteins produced in the baculovirus-expression system are used for instance for functional studies, vaccine preparations, or diagnostics. The vaccines produced by baculovirus-expression system showed elicitation of antibodies. The recombinant baculovirus infected SF9 cells showed broken shape. The recombinant VP2 proteins from cell pellet or supernatant were confirmed by western blotting. The result showed that the recombinant VP2 protein bands were appeared at 65 kDa molecular weight in both cell pellet and supernatant of infected SF9 cell. These results indicated that the recombinant baculovirus infected SF9 cell express the recombinant VP2 protein successfully. In addition, the expressed recombinant VP2 protein is secreted from cell to supernatant. The baculovirus expression system can be used to produce the VP2 protein of CPV 2c. In addition, the secretion property of the expression of VP2 protein may decrease the cost of production, because it can be skipped the cell breaking step. The produced VP2 protein could be used for vaccine and the agent of diagnostic tests. This study provides the foundation of the production of CPV 2c vaccine and the diagnostic agent.

Keywords: baculovirus, canine parvovirus 2c, dog, Korea

Procedia PDF Downloads 151
117 Virtual Prototyping of LED Chip Scale Packaging Using Computational Fluid Dynamic and Finite Element Method

Authors: R. C. Law, Shirley Kang, T. Y. Hin, M. Z. Abdullah

Abstract:

LED technology has been evolving aggressively in recent years from incandescent bulb during older days to as small as chip scale package. It will continue to stay bright in future. As such, there is tremendous pressure to stay competitive in the market by optimizing products to next level of performance and reliability with the shortest time to market. This changes the conventional way of product design and development to virtual prototyping by means of Computer Aided Engineering (CAE). It comprises of the deployment of Finite Element Method (FEM) and Computational Fluid Dynamic (CFD). FEM accelerates the investigation for early detection of failures such as crack, improve the thermal performance of system and enhance solder joint reliability. CFD helps to simulate the flow pattern of molding material as a function of different temperature, molding parameters settings to evaluate failures like voids and displacement. This paper will briefly discuss the procedures and applications of FEM in thermal stress, solder joint reliability and CFD of compression molding in LED CSP. Integration of virtual prototyping in product development had greatly reduced the time to market. Many successful achievements with minimized number of evaluation iterations required in the scope of material, process setting, and package architecture variant have been materialized with this approach.

Keywords: LED, chip scale packaging (CSP), computational fluid dynamic (CFD), virtual prototyping

Procedia PDF Downloads 287
116 Anti-Osteoporotic Effect of Deer Antler in Ovariectomized Rats

Authors: Hye Kyung Kim, Myung-Gyou Kim, Kang-Hyun Leem

Abstract:

The deer velvet antler is well known for its traditional medicinal value and is widely used in the clinic. It has been considered to possess bone-strengthening activity. The goal of this study was to investigate the anti-osteoporotic effect of deer antler velvet on ovariectomized rats (OVX), and their possible mechanism of the action. In the first step, the in vitro effects of DAE on bone loss were determined. The proliferation, collagen content and alkaline phosphatase (ALP) activity of human osteoblastic MG-63 cells and osteoclastogenesis from bone marrow-derived precursor cells were measured. The in vivo experiment confirmed the positive effect of DAE on bone tissue. 3-month old female Sparague-Dawley rats were either sham operated or OVX, and administered DAE (20 and 100 mg/kg) for 4 weeks. DAE increased MG-63 cell proliferation and ALP activity in a dose-dependent manner. Collagen content was also increased by DAE treatment. However, the effect of DAE on bone resorption was not observed. OVX rats supplemented with DAE showed osteoprotective effects as the bone ALP level was increased and c-terminal telopeptide level was decreased by 100 mg/kg DAE treatment compared with OVX controls. Moreover, the tartrate-resistant acid phosphatase-5b level was also decreased by DAE treatment. The present study suggests that DAE is effective in preventing bone loss in OVX rats, and may be potential therapeutic agents for the treatment of postmenopausal osteoporosis.

Keywords: bone ALP, c-terminal telopeptide, deer antler, osteoporosis, ovariectomy, tartrate-resistant acid phosphatase-5b

Procedia PDF Downloads 245
115 A 10-Year In-Depth Follow-up of Post-lingual Hearing Loss Patients with Chinese Domestic Cochlear Implants

Authors: Jianan Li, Lusen Shi, Haiqiao Du, Wei Chen, Qian Wang, Shuoshuo Kang, Shiming Yang

Abstract:

Background: Follow-up of cochlear implant effectiveness is mainly focused on 3 years postoperatively, and studies with more than 5 years of observation are rare, especially for local Chinese brands. Objectives: Nurotron (Chinese domestic cochlear implant brand) CI recipients who participated in the clinical trial in 2009 were followed-up for 10 years prospectively, providing data to guide doctors and patients. Material and Methods: From December 2009 to April 2010, 57 subjects underwent Nurotron Venus CI surgery at multiple centers and were continued to be followed up and assessed at 1, 2, 3, 4, 5, and 10 years after switching on. Results: All recipients were successfully implanted with CIs with no difficulty in subsequent use, with one reported case of re-implantation 9 years after implantation. The aided hearing thresholds were significantly improved one month after switching on (p<0.0001) and remained stable afterward for 10 years. Speech recognition scores were significantly higher than pre-operative results (p<0.05) and continued to improve till 3 years after switching on. At 10 years of post-operation, most subjects had improved QOL scores in most sub-items. Conclusions and Significance: Nurotron Venus CI System provides long-term, stable results in hearing speech assistance capabilities and can improve the quality of life of CI recipients.

Keywords: cochlear implantation, hearing loss, post lingual, follow up

Procedia PDF Downloads 16
114 Sensitivity Based Robust Optimization Using 9 Level Orthogonal Array and Stepwise Regression

Authors: K. K. Lee, H. W. Han, H. L. Kang, T. A. Kim, S. H. Han

Abstract:

For the robust optimization of the manufacturing product design, there are design objectives that must be achieved, such as a minimization of the mean and standard deviation in objective functions within the required sensitivity constraints. The authors utilized the sensitivity of objective functions and constraints with respect to the effective design variables to reduce the computational burden associated with the evaluation of the probabilities. The individual mean and sensitivity values could be estimated easily by using the 9 level orthogonal array based response surface models optimized by the stepwise regression. The present study evaluates a proposed procedure from the robust optimization of rubber domes that are commonly used for keyboard switching, by using the 9 level orthogonal array and stepwise regression along with a desirability function. In addition, a new robust optimization process, i.e., the I2GEO (Identify, Integrate, Generate, Explore and Optimize), was proposed on the basis of the robust optimization in rubber domes. The optimized results from the response surface models and the estimated results by using the finite element analysis were consistent within a small margin of error. The standard deviation of objective function is decreasing 54.17% with suggested sensitivity based robust optimization. (Business for Cooperative R&D between Industry, Academy, and Research Institute funded Korea Small and Medium Business Administration in 2017, S2455569)

Keywords: objective function, orthogonal array, response surface model, robust optimization, stepwise regression

Procedia PDF Downloads 288
113 Comparison of Two Anesthetic Methods during Interventional Neuroradiology Procedure: Propofol versus Sevoflurane Using Patient State Index

Authors: Ki Hwa Lee, Eunsu Kang, Jae Hong Park

Abstract:

Background: Interventional neuroradiology (INR) has been a rapidly growing and evolving neurosurgical part during the past few decades. Sevoflurane and propofol are both suitable anesthetics for INR procedure. Monitoring of depth of anesthesia is being used very widely. SEDLine™ monitor, a 4-channel processed EEG monitor, uses a proprietary algorithm to analyze the raw EEG signal and displays the Patient State Index (PSI) values. There are only a fewer studies examining the PSI in the neuro-anesthesia. We aimed to investigate the difference of PSI values and hemodynamic variables between sevoflurane and propofol anesthesia during INR procedure. Methods: We reviewed the medical records of patients who scheduled to undergo embolization of non-ruptured intracranial aneurysm by a single operator from May 2013 to December 2014, retrospectively. Sixty-five patients were categorized into two groups; sevoflurane (n = 33) vs propofol (n = 32) group. The PSI values, hemodynamic variables, and the use of hemodynamic drugs were analyzed. Results: Significant differences were seen between PSI values obtained during different perioperative stages in both two groups (P < 0.0001). The PSI values of propofol group were lower than that of sevoflurane group during INR procedure (P < 0.01). The patients in propofol group had more prolonged time of extubation and more phenylephrine requirement than sevoflurane group (p < 0.05). Anti-hypertensive drug was more administered to the patients during extubation in sevoflurane group (p < 0.05). Conclusions: The PSI can detect depth of anesthesia and changes of concentration of anesthetics during INR procedure. Extubation was faster in sevoflurane group, but smooth recovery was shown in propofol group.

Keywords: interventional neuroradiology, patient state index, propofol, sevoflurane

Procedia PDF Downloads 181
112 Rank-Based Chain-Mode Ensemble for Binary Classification

Authors: Chongya Song, Kang Yen, Alexander Pons, Jin Liu

Abstract:

In the field of machine learning, the ensemble has been employed as a common methodology to improve the performance upon multiple base classifiers. However, the true predictions are often canceled out by the false ones during consensus due to a phenomenon called “curse of correlation” which is represented as the strong interferences among the predictions produced by the base classifiers. In addition, the existing practices are still not able to effectively mitigate the problem of imbalanced classification. Based on the analysis on our experiment results, we conclude that the two problems are caused by some inherent deficiencies in the approach of consensus. Therefore, we create an enhanced ensemble algorithm which adopts a designed rank-based chain-mode consensus to overcome the two problems. In order to evaluate the proposed ensemble algorithm, we employ a well-known benchmark data set NSL-KDD (the improved version of dataset KDDCup99 produced by University of New Brunswick) to make comparisons between the proposed and 8 common ensemble algorithms. Particularly, each compared ensemble classifier uses the same 22 base classifiers, so that the differences in terms of the improvements toward the accuracy and reliability upon the base classifiers can be truly revealed. As a result, the proposed rank-based chain-mode consensus is proved to be a more effective ensemble solution than the traditional consensus approach, which outperforms the 8 ensemble algorithms by 20% on almost all compared metrices which include accuracy, precision, recall, F1-score and area under receiver operating characteristic curve.

Keywords: consensus, curse of correlation, imbalance classification, rank-based chain-mode ensemble

Procedia PDF Downloads 138
111 Calculating Approach of Thermal Conductivity of 8 YSZ in Different Relative Humidities Corresponding to Low Water Contents

Authors: Yun Chol Kang, Myong Nam Kong, Nam Chol Yu, Jin Sim Kim, Un Yong Paek, Song Ho Kim

Abstract:

This study focuses on the calculating approach of the thermal conductivity of 8 mol% yttria-stabilized zirconia (8YSZ) in different relative humidity corresponding to low water contents. When water content in 8YSZ is low, water droplets can accumulate in the neck regions. We assume that spherical water droplets are randomly located in the neck regions formed by grains and surrounded by the pores. Based on this, a new hypothetical pore constituted by air and water is proposed using the microstructural modeling. We consider 8YSZ is a two-phase material constituted by the solid region and the hypothetical pore region where the water droplets are penetrated in the pores, randomly. The results showed that the thermal conductivity of the hypothetical pore is calculated using the parallel resistance for low water contents, and the effective thermal conductivity of 8YSZ material constituted by solid and hypothetical pore in different relative humidities using EMPT. When the numbers of water layers on the surface of 8YSZ are less than 1.5, the proposed approach gives a good interpretation of the experimental results. When the theoretical value of the number of water layers on 8YSZ surface is 1, the water content is not enough to cover the internal solid surface completely. The proposed approach gives a better interpretation of the experimental results in different relative humidities that numbers of water layers on the surface of 8YSZ are less than 1.5.

Keywords: 8YSZ, microstructure, thermal conductivity, relative humidity

Procedia PDF Downloads 90
110 Shear Behavior of Steel-Fiber-Reinforced Precast/Prestressed Concrete Hollow Core Slabs

Authors: Thi Nguyet Hang Nguyen, Kang Hai Tan

Abstract:

Precast/prestressed concrete hollow core (PCHC) slabs, especially ones with depth more than 300 mm, are susceptible to web-shear failure. The reasons lie on the fact that the production process of PCHC slabs, i.e., the extrusion method (the most common method to cast PCHC slabs nowadays), does not allow them to contain any shear reinforcement. Moreover, due to the presence of the longitudinal voids, cross sections of PCHC slabs are reduced. Therefore, the shear capacity of the slabs depends solely on the tensile strength of concrete which is relatively low. Given that shear is a major concern in using hollow-core slabs, this paper investigates the possibility of adopting steel fibers in PCHC slabs produced by the extrusion method to enhance the shear capacity of the slabs. Three full-scale PCHC slabs with and without hooked-steel fibers were cast and tested until failure. Three different volumetric fiber contents of 0, 0.51 and 0.89% were investigated. The test results showed that there were substantial increases in shear capacity and ductility with the use of hooked-steel fibers. Ultimate shear strength increased with fiber content. In addition, while the specimen without steel fibers and the one with the steel-fiber volume fraction of 0.51% failed in web-shear mode, the specimen with the higher fiber content (0.89%) collapsed in flexural-shear mode. However, as the hooked-steel fibers with the fiber content of 0.89% were used, difficulties in concrete consolidation were observed while concrete was being cast. This could lead to a lower ultimate shear capacity due to a poorer bond between the concrete and the steel fibers.

Keywords: hollow-core slabs, shear strength, steel fibers, web-shear failure

Procedia PDF Downloads 174