• The Korean Journal of Physiology
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• 제26권2호
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• pp.143-150
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• 1992

The purpose of this study is to obtain the effective concentration of capsaicin to relieve pain with no change in the number of C-fibers and its effective duration for pain relief. Capsaicin has been used extremely as a experimental tool and as topical medications for acute or chronic tissue injuries and partial nerve injury is the main cause of causalgiform pain disorders in humans. Here, the left sciatic nerve was ligated unilaterally at the high level of the thigh to prepare an animal model of this pain condition. The rat developed guarding behavior of the ipsilateral hind paw within a few hours after the operation and this behavior was maintained for several months thereafter, suggesting the possibility of spontaneous pain. These animals were divided into two groups(4-week & 8-week) and each group was subdivided into five groups by different concentration (0.05, 0.1, 0.5, 1.0 & 2.0%). Each capsaicin concentration was treated locally on the spinal cord-side of the ligated nerve and the foot withdrawal latency was measured. Thereafter, the dorsal roots of L5 were removed from both sides immediately after in tracardial perfusion for the counting of C-fibers by the histological procedure. There were no significant differences in the foot-withdrawal latency and the number of C-fibers between the left side treated with 0.05% capsaicin and the right side treated with the vehicle. However, latencies of the left sides treated with 0.1, 0.5, and 1.0% capsaicin increased significantly throughout 4-6 weeks with almost no change in the number of C-fibers, and the latencies showed the trends to approach slowly to those of the conditions after operation. The latency of subgroup treated with 2.0% increased by approximate 10% more than that of the right side throughout 8 weeks, and the number of C-fibers decreased by about 30% or more These results suggest that the elevated latency with capsaicin(0.1-1.0%) treatment is due to the inhibition of impulse transmission throughout the primary afferent fiber and the data from 2.0% are due to partial destruction of C-fibers. Therefore, capsaicin concentrations from 0.1% to 1.0% are probably very effective for the treatment of causalgiform pain with almost no destruction of C-fibers.

• 정보처리학회논문지C
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• 제12C권1호
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• pp.121-128
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• 2005

기존 TCP 기술은 송${\cdot}$수신측에 각각 고정된 크기의 버퍼를 할당하기 때문에 높은 대역폭(High-Bandwidth) 및 큰 전송지연(High Delay)을 가진 통신에는 적합하지 못하다. 따라서 종단간의 TCP 처리량을 개선하기 위해 통신망 상황에 따라 자동으로 TCP 버퍼를 조절하려는 시도가 있어왔다. ATBT(Automatic TCP Buffer Tuning)에서 송신측은 현재의 혼잡 제어 윈도우(CWND)의 값에 따라 송신 버퍼 크기를 조절하고 수신측은 운영체제가 정해ens 최대 크기의 TCP 버퍼 값으로 수신 버퍼 크기를 고정한다. DRS(Dynamic Right Sizing) 에서는 이전에 수신한 TCP 데이터의 두 배를 현재 송신할 TCP 데이터라고 예측함으써, TCP 수신측은 단순히 이에 따라 수신 버퍼 크기를 동적으로 변화시킨다. 그렇지만 TCP 세그먼트의 손실 가능성으로 인해 정확히 두 배로 버퍼 크기를 변화시킬 필요는 없다. 따라서 우리가 제안한 패킷 손실률에 기반한 효율적인 TCP 버퍼 조절 알고리즘(TBT-PLR:TCP Buffer Tuning Algorithm based on Packet Loss Ratio)은 TCP 송신측에는 ATBT 방법을 TCP 수신측에는 TBT-PLR 방법을 적용하였다. 실제 TCP 성능을 테스트하기 위해서 리눅스 커널 2.4.18을 수정하여 구현하였으며 기존의 고정된 크기의 TCP 버퍼를 가진 경우와 버퍼 크기가 동적으로 변하는 TBT-PLR을 적용한 경우를 비교하였다. 결과적으로, TCP 연결들간의 균형있는 메모리 사용으로 인해 성능 향상을 얻을 수 있었다.

• 한국치위생학회지
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• 제1권2호
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• pp.181-192
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• 2001

The purpose of this was to evaluate the level of knowledge about Hepatitis B and AIDS among dental hygiene students at six dental hygiene educational programs in nationwide, compare the findings to those of Song's study. 1703 dental hygiene students surveyed by mail and answered a questionnaire, using the questionnaire used developed by DiClemente el al., on Hepatitis B vaccination, antibody production, experience of unintentional needle stick injuries, experience of surgical operation and blood transfusion, personal risk factors for HBV and HIV, management of HBV and HIV postexposure management et al. The data indicated that dental hygiene students (79.0%) in this study had more HIV vaccination than dental hygiene(74.3%) in Song's study. As for recognition of antibody production after Hepatitis B vaccination, only 34.6% of respondents answered they knew having antibody production and 95% of respondents knew not having antibody production. Over one-half of the respondents (55%) answered they didn't even recognize having antibody production. 52.3 percent of dental hygiene students experienced unintentional needle stick injuries. The findings on the knowledge about Hepatitis B and AIDS were that dental hygienists (76.5 points) received higher mean score than those of dental hygiene students (71.0 points) and that the distribution of right answer rate also showed wider range in dental hygiene students (27.7~97.5%) than those of dental hygienist (41.2~99.5%). There were no statistical differences among dental hygiene education programs. Finding of this study support that the curriculum of dental hygiene program should include instruction on sources and methods of transmission of infectious diseases, risk of virus transmission in the workplace and principles of infection control. Furthermore, infection-control practices should be utilized routinely and their application to dental personnel, management of HBV and HIV postexposure management. Furthermore, for preventing the further spread of infectious diseases (HBV, HIV and AIDS${\cdots}$) caused by bloodborne viruses, imposing an obligation rather than recommendation on Hepatitis B vaccination to all dental personnel and routinely utilizing infection-control guidelines for all dental patients in dental practices (include dental educational programs) should be accomplished by coordination the government agency.

• 한국전산구조공학회논문집
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• 제25권6호
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• pp.549-558
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• 2012

본 논문에서는 레벨셋 방법을 이용하여, 소음을 차단하기 위한 음향 구조물의 형상 최적설계를 수행하였다. 형상 최적설계의 목적은 특정한 각도와 각속도로 입사되는 입사파에 대해서 음향 투과율(acoustic transmittance)이 최소가 되도록 음향 결정의 형상(inclusion shape)을 결정하는 것이다. 음향 결정 구조에서는 음향이 흩어져 있는 결정 구조에 의해서 굴절되기 때문에 결정 모양을 조정함으로써, 음향 거동을 제어할 수 있다. 본 연구에서는 음향 구조물로 결정이 수평방향으로는 주기적으로 무한히 분포하고 수직방향으로는 유한한 층간 구조를 가지고 있는 소음 방어벽(Noise barrier)을 고려한다. 주기적 구조물을 고려하기 때문에 결정의 좌와 우에 Bloch 이론을 적용해 주기적 경계조건을 부과하였고, 소음 방어벽 위와 아래에는 임피던스 행렬(impedance matrix)를 이용하여, 무한 균질 영역과 소음 방어벽 사이의 음파 투과를 모사하였다. 결정의 위상과 형상변화를 묘사하기 위해서 레벨셋 방법(level set method)을 사용하였다. 레벨셋 방법에서는 초기 영역을 고정시킨 상태에서, 레벨셋으로 표현되는 임시적 경계(implicit moving boundary)를 변화시킴으로써 복잡한 형상을 다룰 수 있다. 몇몇 수치적 예제를 통해, 제시된 방법의 적용성을 검증하였다.

• 대한전자공학회논문지SP
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• 제41권4호
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• pp.9-21
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• 2004

본 논문에서는 JPEG2000 표준에서 주파수 변환기법으로 채택된 이산 웨이블릿 변환과 선형양자화 방법을 채택하여 영상 전체가 아닌 영상의 부분 데이터만을 암호화하여 암호화를 위한 계산양을 줄이는 방법을 제안하였다. 또한 계산양이 많은 암호화 알고리즘 대신 비교적 계산양이 적은 카오스 시스템을 이용함으로써 계산양을 더욱 감소시켰다. 이 방법은 영상의 압축비를 유지하기 위해서 양자화와 엔트로피 코딩 사이에서 암호화를 수행하며, 부대역의 선택과 카오스 시스템을 이용한 무작위 변환방법을 사용한다. 영상에 대한 실험방법은 우선 암호화할 부대역을 선택한 후 영상데이터를 일정한 블록으로 만든 후 랜덤하게 좌/우로 시프트 하는 방법과 두 가지 양자화 할당 방식(Top-down/Reflection code)을 사용하여 암호화한 데이터를 압축 시 데이터양의 변화를 최소화하였다 또한, JPEG2000의 점진적 전송(Progressive transmission)에 적합한 암호화 방법을 제안하였다. 제안한 방법을 소프트웨어로 구현하여 약 500개의 영상을 대상으로 실험한 결과 원 영상 데이터를 부분적으로 암호화함으로써 원 영상을 인식할 수 없을 정도의 암호화효과를 얻을 수 있음을 알 수 있었다. 따라서 제안한 방법은 작은 양의 암호화로 효과적으로 영상을 숨기는 방법임을 확인할 수 있었다. 본 논문에서는 여러 방식을 제안하였으며, 이들의 암호화 수행시간과 암호화효과 사이에 상보적인 관계가 있음을 보여, 적용분야에 따라 선택적으로 사용할 수 있음을 보였다. 또한 본 논문의 방식들은 응용계층에서 수행되는 것으로, 현재 유 무선 통합 네트워크의 중요한 문제로 대두되고 있는 끝과 끝(end-to-end)의 보안에 대한 좋은 해결방법으로 사용될 수 있으리라 기대된다.

• 한국의학물리학회지:의학물리
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• 제9권3호
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• pp.155-162
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• 1998

방사성 동위원소의 치료에 베타 방출 선원이 많이 이용되고 있다. 베타 방출 핵종 들은 투과력이 약해 방사선 도달거리 (range)가 짧아 병소내에 직접 주입하여 선택적으로 병소만을 조사하여 치료 의 효과를 얻을 수 있고 주변 정상 조직의 방사선 피폭을 줄일 수 있다. 최근 한국 원자력연구소의 원자로인 하나로를 이용하여 베타 입자 방출체인 Ho-l66 용액을 만들어 여기에 키토산 화합물을 표지 하였다. Ho-l66 은 고 에너지 베타 방출체라는 점과 일부 감마선이 방출됨으로써 감마카메라로 쉽게 영상을 얻을 수 있다는 장점이 있다. 본 연구에서는 감마카메라로 얻은 평면 영상을 이용하여 Ho-l66으로 치료한 부위와 그 주변의 정상 장기들의 방사선 홉수선량을 구하였다. 감마카메라는 Siemens 의 2중 head를 가진 Multispect2 시스템이 이용되었고, 콜리메이터는 medium energy, 최대 에너지는 80 keV, 창은 20%로 5분간 영상을 획득하였다. Ho-166 에 대한 투과인자 (transmission factor)는 환자 있을 때와 없을 때의 영상으로 관심영역의 ROIs 의 비로 구하였다 .3일간의 평면 영상으로 유효반감기를 구하여 Marinelli 공식과 MIRD 공식으로 베타입자에 대한 방사선 흡수선량을 구하였다. 감마선에 의한 흡수선량은 매우 적으므로 무시하였다. Transmission factor는 환자에 따라 다르지만 1110 MBq(30 mCi)을 주입하여 치료에 임한 간암 환자의 경우 간은 4.6, 비장은 4.65, 폐는 3.34, 뼈는 5.65 의 값을 보였다. 방사선 홉수선량은 tumor 에는 179.7, 정상간에는 16.3, 비장은 18.5, 폐에는 7.0, 뼈에는 9.0 Gy 가 각각 계산되었다. 이를 tumor dose 에 100%로 normalization 시킬 경우 정상간, 비장, 폐, 뼈에 각각 9.1, 10.3, 3.9, 5.0%로 분포되었음을 알았다. 본 연구를 통하여 tumor dose 뿐만이 아니고 주변 주요 위험장기 (critical organ) 에 대한 방사선 흡수선량을 전ㆍ후면 평면영상으로 얻을 수 있음을 보여 줌으로써 평면영상법을 이용한 dosimetry 의 가능성을 보았다. 또한 주변 주요 위험 장기의 한계선량에 맞는 주입할 양을 결정하는데 기초 자료가 될 수 있음을 보여준다.

• The Korean Journal of Physiology and Pharmacology
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• 제9권1호
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• pp.23-27
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• 2005

The present study was performed to investigate the effects of intra-articular injection of interleukin-1${\beta}$ (IL-1${\beta}$) on the formalin-induced temporomandibular joint (TMJ) pain. Under anesthesia, a 30-gauge needle was introduced into the right TMJ region for injection of formalin. Microinjection of 50 ${\mu}l$ of 5% formalin significantly produced noxious scratching behavioral response, and the scratching behavior lasted for 40 min. Although the responses produced by formalin injection were divided into two phases, the response of 1st phase did not significantly differ from the scratching behavior response in the saline-treated group. We examined the effects of intra-articular injection of IL-1${\beta}$ on the number of noxious behavioral responses produced by 50${\mu}l$ of 5% formalin injection. Intra-articular injection of 100 pg and 1 ng of IL-1${\beta}$ significantly increased the number of behavioral responses of the 2nd phase, while 10 pg of IL-1${\beta}$ did not change the formalin-induced behavioral responses. To investigate whether IL-1 receptor was involved in the intra-articular administration of IL-1${\beta}$-induced hyperalgesic response, IL-1 receptor antagonist (IL- ra, 50 ng) was administrated together with IL-1${\beta}$ injection. IL-1${\beta}$ receptor antagonist blocked IL-1${\beta}$- induced hyperalgesic response in the TMJ formalin test. These results suggest that intra-articular injection of IL-1${\beta}$ facilitated the transmission of nociceptive information in the TMJ area.

• ALGAE
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• 제36권4호
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• pp.241-261
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• 2021

Amphidinium species are amongst the most abundant benthic dinoflagellates in marine intertidal sandy ecosystems. Some of them produce a variety of bioactive compounds that have both harmful effects and pharmaceutical potential. In this study, Amphidinium cells were isolated from intertidal sand collected from the East China Sea. The two strains established were subjected to detailed examination by light, and scanning and transmission electron microscopy. The vegetative cells had a minute, irregular, and triangular-shaped epicone deflected to the left, thus fitting the description of Amphidinium sensu stricto. These strains are distinguished from other Amphidinium species by combination characteristics: (1) longitudinal flagellum inserted in the lower third of the cell; (2) icicle-shaped scales, 276 ± 17 nm in length, on the cell body surface; (3) asymmetrical hypocone with the left side longer than the right; and (4) presence of immotile cells. Therefore, they are described here as Amphidinium stirisquamtum sp. nov. The molecular tree inferred from small subunit rRNA, large subunit rRNA, and internal transcribed spacer-5.8S sequences revealed that A. stirisquamtum is grouped together with the type species of Amphidinium, A. operculatum, in a fully supported clade, but is distantly related to other Amphidinium species bearing body scale. Live A.stirisquamtum cells greatly affected the survival of rotifers and brine shrimp, their primary grazers, making them more susceptible to predation by the higher tropic level consumers in the food web. This will increase the risk of introducing toxicity, and consequently, the bioaccumulation of toxins through marine food webs.

• 한국패류학회지
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• 제27권2호
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• pp.121-129
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• 2011

The ultrastructural characteristics of germ cell development during spermatogenesis and mature sperm morphology of in male Scapharca subcrenata were investigated by transmission electron microscope observation. Spermatogonia are located nearest the outer wall of the acinus, while spermatocytes and spermatids are positioned near the accessory cells. The accessory cells, which is in close contact with developing germ cells, contained a large quantity of glycogen particles and lipid droplets in the cytoplasm. Therefore, it is assumed that they are involved in supplying of the nutrients for germ cell development. The morphologies of the sperm nucleus and the acrosome of this species are the oval shape and cone shape, respectively. Spermatozoa are approximately 45-$50{\mu}m$ in length including a sperm nucleus (about $1.30{\mu}m$ in length), an acrosome (about $0.59{\mu}m$ in length), and tail flagellum (about 43-$47{\mu}m$). The axoneme of the sperm tail shows a 9 + 2 structure. As some characteristics of the acrosomal vesicle structures, the right and left basal rings show electron opaque part (region), and also the anterior apex part of the acrosomal vesicle shows electron opaque part (region). These characteristics of the acrosomal vesicle were found in Acinidae and other several families in subclass Pteriomorphia. These common characteristics of the acrosomal vesicle in subclass Pteriomorphia can be used for phylogenetic and taxonomic analysis as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as one of common characteristics appear in most species in Arcidae and other families in subclass Pteriomorphia. The acrosomal vesicles of Arcidae species do not contain the axial rod and several transverse bands in acrosome, unlkely as seen in Ostreidae species in subclass Pteriomorphia, These characteristics can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or tools.

• Smart Structures and Systems
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• 제18권4호
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• pp.643-662
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• 2016

The monitoring of structural integrity of pipeline tapered thread connections is of great significance in terms of safe operation in the industry. In order to detect effectively the loosening degree of tapered thread connection, an active sensing method using piezoceramic transducers was developed based on time reversal technique in this paper. As the piezoeramic transducers can be either as actuators or sensors to generate or detect stress waves, the energy transmission for tapered thread connection was analyzed. Subsequently, the detection principle for tapered thread connection based on time reversal was introduced. Finally, the inherent relationship between the contact area and tightness degree of tapered thread connection for the pipe structural model was investigated. Seven different contact area scenarios were tested. Each scenario was created by loosening connectors ranging from 3 turns to 4.5 turns in the right tapered threads when the contact area in the left tapered threads were 4.5 turns. The experiments were separately conducted with a highly noisy environment and various excitation signal amplitudes. The results show the focused peaks based on time reversal have the monotonously rising trend with the increase of the contact areas of tapered threads within an acceptable monitoring resolution for metal pipes. Compared with the energy method, the proposed time reversal based method to monitor tapered threads loosening demonstrates to be more robust in rejecting noise in Structural Health Monitoring (SHM) applications.