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Effect of Stem Cell Transplantation on Pain Behavior and Locomotor Function in Spinal Cord Contusion Model

  • Park, Hea-Woon;Kim, Su-Jeong;Cho, Yun-Woo;Hwang, Se-Jin;Lee, Won-Yub;Ahn, Sang-Ho;Jang, Sung-Ho
    • The Journal of Korean Physical Therapy
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    • v.22 no.3
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    • pp.79-85
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    • 2010
  • Purpose: Many trials for new therapeutic approaches such as stem cell-based transplantation have been conducted to improve the repair and regeneration of injured cord tissue and to restore functions following spinal cord injury (SCI) in animals and humans. Adipose tissue-derived stromal cells (ATSCs) have multi-lineage potential to differentiate into cells with neuron-like morphology. Most studies of stem cell transplantation therapy after SCI are focused on cellular regeneration and restoration of motor function, but not on unwanted effects after transplantation such as neuropathic pain. This study was focused on whether transplantation of ATSCs could facilitate or attenuate hindpaw pain responses to heat, cold and mechanical stimulation, as well as on improvement of locomotor function in a rat with SCI. Methods: A spinal cord injury rat model was produced using an NYU impactor by dropping a 10 g rod from a height of 25 mm on to the T9 segment. Human ATSCs (hATSCs; approximately $5{\times}10^5$ cells) or DMEM were injected into the perilesional area 9 days after the SCI. After transplantation, hindpaw withdrawal responses to heat, cold and mechanical allodynia were measured over 7 weeks. Motor recovery on the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale and on the inclined plane test were also evaluated. Results: The present study demonstrated that increased hindpaw withdrawal responses to cold allodynia was observed in both groups after transplantation, but the development of cold-induced allodynia in the hATSC transplantation group was significantly larger than in the control group. The difference between the two groups in locomotor functional improvement after SCI was also significant. Conclusion: Careful consideration not only of optimal functional benefits but also of unintended side effects such as neuropathic pain is necessary before stem cell transplantation therapy after SCI.

Seismic performance evaluation of middle-slab vibration damping rubber bearings in multi-layer tunnel through full-scale shaking table (실대형 진동대 시험을 통한 복층터널 중간 슬래브 진동 감쇠 고무받침 내진성능 평가)

  • Jang, Dongin;Park, Innjoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.4
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    • pp.337-346
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    • 2020
  • Traffic jam and congestion in urban areas has caused the need to improve the utility of underground space. In response, research on underground structures is increasingly being conducted. Notably, a double-deck tunnel is one of the most widely used of all those underground structures. This double-deck tunnel is separated by the middle slab into the upper and lower roadways. Both vehicle load and earthquake load cause the middle slab to exhibit dynamic behavior. Earthquake-related response characteristics, in particular, are highly complex and difficult to interpret in a theoretical context, and thus experimental research is required. The aim of the present study is to assess the stability of a double-deck tunnel's middle slab of the Collapse Prevention Level and Seismic Category 1 with regard to the presence of vibration-damping Rubber Bearings. In vibration table tests, the ratio of similitude was set to 1/4. Linings and vibrating platforms were fixed during scaled model tests to represent the integrated behavior of the ground and the applied models. In doing so, it was possible to minimize relative behavior. The standard TBM cross-section for the virtual double-deck tunnel was selected as a test subject. The level of ground motion exerted on the bedrock was set to 0.154 g (artificial seismic wave, Collapse Prevention Level and Seismic Category 1). A seismic wave with the maximum acceleration of 0.154 g was applied to the vibration table input (bedrock) to analyze resultant amplification in the models. As a result, the seismic stability of the middle slab was evaluated and analyzed with respect to the presence of vibration-damping rubber bearings. It was confirmed that the presence of vibration-damping rubber bearings improved its earthquake acceleration damping performance by up to 40%.

Correlation of Experimental ana Analytical Inelastic Responses of 1:12 Scale Irregular High-Rise RC Buildings (1:12축소 비정형 고층 RC 건물의 비선형거동에 대한 실험과 해석의 상관성)

  • Ko, Dong-Woo;Lee, Han-Seon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.11 no.2 s.54
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    • pp.95-104
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    • 2007
  • Three types of high-rise RC building structures having irregularity in the lower two stories were selected as prototypes and were performed nonlinear static analysis by using OpenSees to verify the analysis technique and to investigate the seismic capacity of those buildings. The first one has a symmetrical moment resisting frame (Model 1), the second has an infilled shear wall in the central frame (Model 2), and the third has an infilled shear wall only in one of exterior frames (Model 3). Fiber model, which consists of concrete and reinforcing bar represented from stress-strain relationship, is adapted used for simulate the nonlinearity of members, and MVLEM(Multi vertical linear element model) is used for simulate the behavior of wall. The analytical results are simulate the behavior of piloti stories well, for example, the stiffness and yield farce of piloti stories, the up-lift of wall and the variation of lateral stiffness of column due to the variation of axial forces. Overstrength of Model 2 and Model 3 are about 2 times larger than that of Model 1. The reason of the high oversttrength and ductility of Model 2 and Model 3 is that the conservative design of Model 2 and Model 3, whose beam and column sections are the same as those of Model 1. The ductilities of Model 1 and Model 3 are slightly larger than that of Model 1 and Model 3. Model 1 and Model 3 reached mechanism condition, whereas Model 2 failed to the shear failure of shear wall and the large axial forces in columns due to large overturning moment.

An early warning and decision support system to reduce weather and climate risks in agricultural production

  • Nakagawa, Hiroshi;Ohno, Hiroyuki;Yoshida, Hiroe;Fushimi, Erina;Sasaki, Kaori;Maruyama, Atsushi;Nakano, Satoshi
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.303-303
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    • 2017
  • Japanese agriculture has faced to several threats: aging and decrease of farmer population, global competition, and the risk of climate change as well as harsh and variable weather. On the other hands, the number of large scale farms is increasing, because farm lands have been being aggregated to fewer numbers of farms. Cost cutting, development of efficient ways to manage complicatedly scattered farm lands, maintaining yield and quality under variable weather conditions, are required to adapt to changing environments. Information and communications technology (ICT) would contribute to solve such problems and to create innovative technologies. Thus we have been developing an early warning and decision support system to reduce weather and climate risks for rice, wheat and soybean production in Japan. The concept and prototype of the system will be shown. The system consists of a weather data system (Agro-Meteorological Grid Square Data System, AMGSDS), decision support contents where information is automatically created by crop models and delivers information to users via internet. AMGSDS combines JMA's Automated Meteorological Data Acquisition System (AMeDAS) data, numerical weather forecast data and normal values, for all of Japan with about 1km Grid Square throughout years. Our climate-smart system provides information on the prediction of crop phenology, created with weather forecast data and crop phenology models, as an important function. The system also makes recommendations for crop management, such as nitrogen-topdressing, suitable harvest time, water control, pesticide spray. We are also developing methods to perform risk analysis on weather-related damage to crop production. For example, we have developed an algorism to determine the best transplanting date in rice under a given environment, using the results of multi-year simulation, in order to answer the question "when is the best transplanting date to minimize yield loss, to avoid low temperature damage and to avoid high temperature damage?".

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Use of a Temperature as a Tracer to Study Stream-groundwater Exchange in the Hyporheic Zone (열추적자를 이용한 지하수-하천수 혼합대 연구)

  • Kim, Kue-Young;Chon, Chul-Min;Kim, Tae-Hee;Oh, Jun-Ho;Jeoung, Jae-Hoon;Park, Seung-Ki
    • Economic and Environmental Geology
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    • v.39 no.5 s.180
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    • pp.525-535
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    • 2006
  • A study on stream-groundwater exchange was performed using head and temperature data of stream water, streambed, and groundwater. Groundwater level and temperature were obtained from multi-depth monitoring wells in small-scale watershed. During the summer and winter season, time series of temperature data at streambed and groundwater were monitored for six months. In the winter time, we measured the temperature gradient between stream water and streambed. The observed data showed three typical types of temperature characteristics. First, the temperature of streambed was lower than that of stream water; second, the temperature of streambed and stream water was similar; and the last, the temperature of streambed was higher than that of stream water. The interconnections between the stream and the streambed were not homogeneously distributed due to weakly developed sediments and heterogeneous bedrock exposed as bed of the stream. The temperature data may be used in formal solutions of the inverse problems to estimate groundwater flow and hydraulic conductivity.

A Study on the Islamic terrorism in the Southeast Asia: Its Evaluation and perspectives (동남아시아 이슬람 테러리즘 현황 및 전망에 관한 연구)

  • Choi, Jin-Tai
    • Korean Security Journal
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    • no.14
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    • pp.549-567
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    • 2007
  • In the post-Cold war world, the threat of terrorism is emerging as the most formidable challenge. The terrorist attacks including 9.11 World Trade Center attack have proved such challenge. It has become apparent that no country is safe from the scourage of terrorism. The region of the southeast Asia is no exception to this trend. The Bali bombing of 2002, killing about 200 innocent people, demonstrated that the threat environment had significantly altered. Today, local and regional groups such as Jemiah Islamiah can conduct terrorist operations as devastating as those carried out by Al Qaeda. As fighting terrorism is a complex multi-dimensional task, the responsibility for fighting terrorism must not rest with a single government. The burden must be shared by both the local governments and international communities. In addition, To prevent another bombing of the scale of Bali, countries in the region of southeast Asia must respond decisively. The purpose of this study is to examine the current situation on terrorism in the southeast Asia and to provide perspectives on future terrorism in this region. To foster the better understanding, historical survey on the terrorism in the region and local terrorist groups' network with the foreign terrorist organizations including Al Qaeda have been researched. Based on the result of the research, this paper provides a perspectives and evaluation on the future terrorism in the southeast Asia. It also provides an implications for our reference in the war against terrorism.

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Strength Development of Fiber Reinforced Lean Concrete Using Fly Ash and Reject Ash under Different Compaction Methods including Small Scale Roller Vibrator (플라이애쉬와 리젝트애쉬를 활용한 섬유보강 빈배합 콘크리트의 강도 특성 및 롤러다짐을 활용한 현장적용 실험)

  • Kim, Seung-Won;Jang, Young-Jae;Park, Young-Hwan;Park, Cheol-Woo
    • Journal of the Korea Concrete Institute
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    • v.24 no.5
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    • pp.543-551
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    • 2012
  • Road pavements in Korea generally show shorter service life than the predicted one. There are many reasons for this phenomenon including increased traffic load and other attacks from exposure conditions. In order to extend a service life and upgrade the pavement, a new multi-functional composite pavement system is being developed in Korea. This study is to investigate the performances of fiber-reinforced lean concrete for pavement base. This study considered mineral admixtures of fly ash and reject ash. The reject ash is defined as ash that does not meet the specifications for fly ash so that it cannot be used as a supplemental material for cement replacement. Due to the inherent property of lean concrete, compaction during the fabrication of specimens is a key factor. Therefore, this study suggests an appropriate compaction method. From the test results, the compressive strengths of the concrete satisfied the required limit of 5 MPa at 7 days. When a compaction roller was used to mimic actual field conditions, the strength development seemed to be influenced by the compaction energy rather than hydration of cement itself.

Re-Examination of Opisthorchis viverrini in Nakhon Ratchasima Province, Northeastern Thailand, Indicates Continued Needs for Health Intervention

  • Kaewpitoon, Soraya J;Rujirakul, Ratana;Loyd, Ryan A;Panpimanmas, Sukij;Matrakool, Likit;Tongtawee, Taweesak;Kompor, Porntip;Norkaew, Jun;Chavengkun, Wasugree;Kujapan, Jirawoot;Polphimai, Sukanya;Phatisena, Tanida;Eaksunti, Thawatchai;Polsripradist, Poowadol;Padchasuwan, Natnapa;Kaewpitoon, Natthawut
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.231-234
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    • 2016
  • Opisthorchis viverrini infection is associated with cholangiocarcinoma particularly in the cases of chronic or re-infection. This presents a serious health problem in northeastern and northern Thailand. A community base approach is required for surveillance. Therefore, in a pilot project, re-examination of O. viverrini infection was conducted in the 3 districts of Nakhon Ratchasima province, Thailand, during June and October 2015. A total of 355 participants from a 194,152 population, was selected through multi-stage sampling. O. viverrini infection was determined using modified Kato Katz thick smear technique. Participants were 229 males and 126 females, and aged ${\geq}30$ years old. Prevalence of O. viverrini infection was 2.25% (8/355 participants). O. viverrini infection was slightly higher in females (3.17%), and age group between 41-50 years (4.49%). Mueang Yang district had a highest of O. viverrini infection rate (2.82%), and followed by Bua Yai (2.48%), and Chum Phuang (1.84%), respectively. O. viverrini infection rate was increased from year 2012 to 2015 particularly in Bua Yai and Mueang Yang. These re-examinion results indicate that opisthorchiasis is still problem in community of Nakhon Ratchasima province, therefore, the provincial-wide scale is need required. Furthermore health education is need intervened in the infected group, and screening of cholangiocarcinoma is urgently concerned.

Utilization of Induced Polarization and Electrical Resistivity for Identifying Rock Condition (유도분극 전하 충전성과 전기비저항을 활용한 암반 상태 파악 가능성 연구)

  • Park, Jinho;Ryu, Jinwoo;Jung, Jeehee;Lee, In-Mo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.3
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    • pp.493-502
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    • 2016
  • This study examines how rock condition affects the variation of the chargeability and electrical resistivity of the rock. In the theoretical study, the relationship correlating chargeability with the variables affecting it is derived. A parametric study utilizing the derived relationship reveals that the size of narrow pores ($r_1$) is the most influential factor on chargeability, and the salinity of pore water ($C_0$) is the second. In the laboratory experiments, small scale rock fracturing zone is modelled using sand stone. Chargeability and resistivity are measured by changing the size of the joint aperture, the location of fractured zone and the existence of clay gouge and/or clay layer which shows lower chargeability than the sand stone layer in the multi-layered ground. Test results show that chargeability is controlled not by the rock fracturing condition but by the size of narrow pore ($r_1$) where each line of current flow passes through. Also, the chargeability decreases with increase of the pore water salinity ($C_0$). In conclusion, the ground condition can be identified more efficiently by measuring the induced polarization along with the electrical resistivity; identifying the existence of sea water, the layered ground and/or the fractured rock becomes more reliable.

New Flood Hazard Mapping using Runoff Mechanism on Gamcheon Watershed (유출메커니즘을 활용한 감천유역에서의 새로운 홍수위험지도 작성)

  • Kim, Tae Hyung;Han, Kun Yeun;Park, Jun Hyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.6
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    • pp.1011-1021
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    • 2016
  • This study performs the potential flood hazard analysis by applying elevation data, soil data and land use data. The susceptibility maps linked to elevation, soil and land use are combined to develop the new types of flood hazard map such as runoff production map and runoff accumulation map. For the development of the runoff production map, land use, soil thickness, permeability, soil erosion and slope data are used as runoff indices. For the runoff accumulation map, elevation, knick point and lowland analysis data are used. To derive an integrated type of flood potential hazard, a TOPSIS (The Technique for Order of Preference by Similarity to Ideal Solution) technique, which is widely applied in MCDM (Multi-Criteria Decision Making) process, is adopted. The indices applied to the runoff production and accumulation maps are considered as criteria, and the cells of analysis area are considered as alternatives for TOPSIS technique. The model is applied to Gamcheon watershed to evaluate the flood potential hazards. Validation with large scale data shows the good agreements between historical data and runoff accumulation data. The analysis procedure presented in this study will contribute to make preliminary flood hazard map for the public information and for finding flood mitigation measures in the watershed.