• Toxicological Research
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• 제23권4호
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• pp.391-403
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• 2007

The study was conducted to assess the repeated dose and reproduction and developmental toxicities of acetanilide, an intermediate for drug production, as a part of OECD Screening Information Data Set (SIDS) program. The test agent was administered by gavage at dose levels of 0, 22, 67, 200 and 600 mg/kg to Sprague-Dawley rats (12/group/sex) during pre-mating and mating period for males(up to 30 days) and females and pregnancy and early lactation period for females (up to 39-50 days). At 22 mg/kg, decreases in HGB, HCT (males) and MCHC (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow (both sexes) were observed. At 67 mg/kg, salivation (males), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC (males), increases in MCV (males) and spleen weight (males), hyperplasia of spleen red pulp and femur bone marrow (both sexes) were observed. At 200 mg/kg, decreases in locomotor activity and salivation (both sexes), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and increases in MCV, MCH, BUN, T-BIL (males), enlargement of spleen (both sexes), increased weight of spleen (males), hyperplasia of spleen red pulp and femur bone marrow and extramedullary hematopoiesis of liver (both sexes), atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. At 600 mg/kg, decreases in locomotor activity, cyanosis (both sexes), reddish tear, and salivation (males), mortality (4 out of 12 females), decreased body weight (females), reduced food consumption (both sexes), decreases in RBC, HGB, HCT and MCHC and increases in WBC, MCV, MCH, reticulocyte, neutrophil, lymphocyte, monocyte, AST, ALT, BUN, T-BIL, ALB, Ca and A/G ratio (males), enlargement of spleen, increased weights of spleen (both sexes), liver (males), kidney and ovary, decreased weights of thymus (females), hyperplasia of spleen red pulp, hyperplasia of femur bone marrow and extramedullary hematopoiesis of liver (both sexes), and atrophy of thymus and corpus luteum hyperplasia of ovary (females) were observed. Regarding the reproduction and development toxicities, there were no treatment-related changes in precoital time, mating index, fertility index and pregnancy index at all doses tested. At 22 and 67 mg/kg, there were no adverse effects on all the parameters observed. At 200 mg/ kg, decreased body weight of pups (day 4 p.p.) were observed. At 600 mg/kg, decreased body weight of pups (day 0 and 4 p.p.) and viability index (day 4 p.p.), increased incidence of newborns dead or with abnormal clinical signs were observed. The results suggest that the NOAELs for general toxicity are < 22 mg/kg, LOAELs are 22 mg/kg and the NOAELs for reproductive toxicity are 67 mg/kg.

• 한국동물위생학회지
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• 제18권1호
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• pp.41-56
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• 1995

The present study was conducted to investigate results of B. anthracis isolated from Anthrax in the Kyong-Ju of Feb. 12. 1994. 1. In biochemical feature, B. anthracis was a gram-positive rod, non-motility, sporulation, capsulation. It was positive in gelatinase, starch hydrolysis, glucose. But negative in urease, arabinose, mannitol, xylose. 2. B. anthracis grew well on B4 Br A TSA after incubation for 24 hours. The organisim grew well on BA, Br. A, NA, TSA after incubation for 72 hours. The media grew well on Br A instead of BA. 3. On 5% blood agar by laboratory animal, ${\beta}$ -hemolysis was produced from 36 hours to 48 hours incubation. There was perfect ${\beta}$-hemolysis after incubation for 48 hours. On the other side ${\beta}$-hemolysis was begun on 5% goat blood agar after incubation for 60 hours. 4. In the test of antimicrobial susceptibility, B. anthracis was very sensitive to AM, CF, TE, ENR, GM, AN, DFX, S, P, TYLO, N, KM, C, E, Lins＋Sp, NN, CC, CFP, CB were sensitive one by one. B. anthracis was no-sensitive to L, XNL, TIA, CL, SXT 5. B. anthracis had never sensitivity to direct inoculation of rat and chicken, after subcutanous inj. It was very sensitive to mouse and goat, hamster, guinea pig, rabbit had a sensibility one by one. 6. The dead laboratory animal which had been inoculated with B. anthracis preserved at $37^{\circ}C$ incubation, B. anthracis didn't cultivate on non-dissected animal after 80 hours but cultivate on dissected animal after 360 hours. 7. The rapidly death could cause high concentration, died from 420 after S. C. 8. The blood smeared samples of hamster from inoculation with B. anthracis, spore germinated In 37$^{\circ}C$ after 5 hours, in $32^{\circ}C$ after 6 hours, in room temperature after 9 hours, in $-4^{\circ}C$ to $-20^{\circ}C$ after 10 hours. 9. B, anthracis inoculated to laboratory animal after SC or PO. Mice and rats feces didn't cultivated with B. anthracis after SC, but did cultivated with B. anthracis after PO. 10. In the test of disinfectant, B. anthracis was high effective to $HgC1_2$, formalin, effect phenol, cresol, but non-effect NaOH, ethanol.

• 한국동물위생학회지
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• 제18권2호
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• pp.113-123
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• 1995

The present study was conducted to investigate the prevalent characteristics of Fowl Typhoid and antibiotic susceptibility of Salmonella gallinarum isolated from 56 infective or dead chickens of 20 egg laying farms in Kyung Buk province during the period from August to December 1994. 1. Among 416, 000 chickens of 92 flocks in 20 egg laying farms, 17, 360 chickens of 31 flocks were died of Fowl Typhoid. 2. Salmonella gallinarum was isolated from 56 chickens in liver and spleen, and then blood of infective chickens was positive to Pullorum antigen. 3, In the survey of gross lesion of 56 chickens, 43 chickens(76.8%) were swelled at liver, 39(69.6%) were swelled at spleen, 12(21.4%) were changed with bronze, 3(5.4% ) were hemorrhagic in peritoneal cavity. 4. In transmission pattern, 4 farms were outbreaked the entrance of chicken house at first, but the others were outbreaked at various place. They were transmitted at right and left directions in flock. 5. 2 farms confirmed at the early stage of infection were eradicated by removing infective chickens and administrating antibiotics, but 18 farms at chronic stage were not. 6. The biochemical properties of 112 Salmonella gallinarum from chickens were generally identical to those of the referance, but H$_2$S was not productive, cellobiose was fermentive. 7 Minimum inhibitory concentration(MIC) of 20 isolates was performed by using 21 antibiotics, MICs of Amikacin(Ak), Gentamicin(Gm), Kanamycin(Km), and Tetracycline (Tc) were below 1.6 ug/ml, Ampicillin(Am), Furazolidone(Fu) and Neomycin(Nm) were below 3.1 ug/ml, Cephalothin(Ce), Cefazoline(Cf) and Chloramphenicol(Cm) were below 6.3 ug/ml, Nalidixic acid(Na), Polymyxin(Po) and Rifampicin(Rf) were below 12.5 ug/ml, Penicillin (Pm) was below 25 ug/ml, Colistin(Co) and Streptomycin(Sm) were below 50 ug/ml, Sulfamerazine(Sr) and Sulfamethazine (St) were below 200 ug/ml, Lincomycin(Lm) and Spiramycin(Sp) were below 400 ug/ml, Bacitracin(Ba) was below 800 ug/ml. 8. Among the 20 isolates, all(100%) of those were sensitive to Ak, Am, Ce, Cf, Cm, Fu, Gm, Km, Na, Nm, Po, Rf, Sr, St and Tc, but 6 isolates(30%) were resistent to Co, 20(100% ) to Ba, Lm, Pm, Sm, and Sp. The drug resistance patterns were simple which 6 strains were BaCoLmPmSmSp type, and 14 were BaLmPmSmSp type.

• 대한미생물학회지
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• 제35권3호
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• pp.251-261
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• 2000

V. vulnificus is an estuarine bacterium which causes septicemia and shock in susceptible patients. The organism produces a hemolytic cytolysin (VvH), which has a membrane damaging effect on erythrocytes. To clarify the mechanisms by which VvH might contribute to virulence, we examined its effect on macrophages. When mouse peritoneal macrophages were harvested and co-cultured with hemolysin-positive V. vulnificus strains (100 bacteria/cell), about 60% of the macrophages were killed; macrophages were not killed when co-cultured V. vulnificus strain CVD 707, a VvH-negative deletion mutant. Exposure of macrophages to filtered culture supernatants (2.5 HU/ml) and purified VvH (3 HU/ml) resulted in an increase in dead cells (80 and 90%, respectively), as determined by the trypan blue dye exclusion method and LDH release from macrophages was also increased (70 and 65.5%, respectively). The cytotoxic effect of VvH on macrophages was both the dose- and time-dependent. The VvH caused damage to the macrophage membrane and was blocked significantly by preincubation with cholesterol (p<0.01). Fetal bovine serum showed remarkable inhibition of VvH synthesis by V. vulnificus and inhibited VvH activity in culture supernatant. Cell viability was increased by 35% (p<0.01) and LDH release decreased by 28% (p<0.01) when macrophages were incubated with V. vulnificus (100 bacterial cell) in DMEM-10% FBS for 2 hr. Bacterial clearance activity of mice against V. vulnificus CVD 707 was decreased by pretreatment with 10 HU of VvH. This result suggests that the VvH can impair the membrane of macrophages and may playa role in the pathogenesis of V. vulnificus septicemia.

• 기본간호학회지
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• 제6권3호
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• pp.522-531
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• 1999

This research identifies the ingress to egress primary factors that causes a patient to receive delayed emergency medical care. This material was collected between February 1st to 28th, 1998. Research envolved 4,118 people who visited the college emergency medical center in Kyeongido Province, South Korea. Medical records were examined, using the retrospective method. to determine the length of stay and the main cause for waiting. Results are as follows : 1. The age group with the highest admission rate was 10 and under, approximately 1,394 (33.9%). Followed by an even distribution for ages between 11-50 at 10-15% for their respective ranges. The lowest admission rate was 50 years and above. 2. From the 4,118 records examined, 3,489 received outpatient treatment (84.7%); 601 were admitted for inpatient care (14.6%); 25 arrived dead on arrival (0.6%); and 4 people died at the hospital. 3. Between 7PM to 12AM, 42.9% were admitted to the EMC. The hours from 9PM to 11PM recorded the highest admission rate and 5AM to 8AM was the lowest From 8PM to 12AM, the most beds were occupied. 4. For most patients. the average length of stay was approximately 2.2 hours. By medical department, external medicine was the longest for 2.8 hours. Pediatrics was the shortest for 1.6 hours. The average waiting period for inpatient admission was 2.6 hours. Inpatient admission for pediatrics and external medicine was 3.4 hours and 2.2 hours respectively. 5. Theses are primary factors for delay at EMC: 1) pronged medical consultations to decide between inpatient versus outpatient treatment, and delaying to be inpatient, 2) when you call physicians they are delayed to come 3) Understaffing during peak or critical hours, 4) Excessive consulting with different medical departments, 5) some patients require longer monitoring periods, 6) medical records are delayed in transit between departments, 7) repeated laboratory tests make delay the result, 8) overcrowded emergency x-ray place causes delay taking x-ray and portable x-ray, 9) the distance between EMC and registration and cashier offices is too far. 10) hard to control patient's family members. The best way to reduce EMC waiting and staying time is by cooperation between departments, both medical and administrative. Each department must work beyond their job description or duty and help each other to provide the best medical service and satisfy the patient needs. The most important answer to shortened the EMC point from ingress to egress is to see things from a patient point of view and begin from there to find the solution.

• 전자공학회논문지C
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• 제35C권11호
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• pp.21-30
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• 1998

본 논문에서는 FPGA를 이용하여 산업용 구동장치로 널리 사용되고 있는 유도 전동기의 디지털 전류 제어시스템을 구현하였다. 이를 위해 VHDL을 이용하여 FPGA를 설계하였으며 이 FPGA는 PWM 발생부, PWM 보호부, 회전속도 검출부, 프로그램 폭주 방지부, 인터럽트 발생부, 디코더 로직부, 신호 지연 발생부 및 디지털 입·출력부로 각각 구성되어있다. 본 FPGA의 설계시 고속처리의 문제점을 해결하기 위해 클럭전용핀을 활용하였으며 또한 40 MHz에서도 동작할 수 있는 삼각파를 만들기 위해 업다운 카운터와 래치부를 병렬 처리함으로써 고속화하였다. 특히 삼각파와 각종 레지스터를 비교 연산할 때 많은 팬아웃 문제에 따른 게이트 지연(gate delay) 요소를 줄이기 위해 병렬 카운터를 두어 고속화를 실현하였다. 아울러 삼각파의 진폭과 주파수 및 PWM 파형의 데드 타임 등을 소프트웨어적으로 가변 하도록 하였다. 이와 같은 기능들을 FPGA로 구현하기 위하여 퀵로직(Quick Logic)사의 pASIC 2 SpDE와 Synplify-Lite 합성툴을 이용하여 로직을 합성하였다. 또한 Verilog HDL 환경에서 최악의 상황들(worst cases)에 대한 최종 시뮬레이션이 성공적으로 수행되었다. 아울러 구현된 FPGA를 84핀 PLCC 형태의 FPGA로 프로그래밍 한 후 3상 유도전동기의 디지털 전류 제어 시스템에 적용하였다. 이를 위해 DSP(TMS320C31-40 MHz)와 FPGA, A/D 변환기 및 전류 변환기(Hall CT) 등을 이용하여 3상 유도 전동기의 디지털 전류 제어 시스템을 구성하였으며, 디지털 전류 제어의 효용성을 실험을 통해 확인하였다.

• 전자공학회논문지SC
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• 제38권1호
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• pp.1-13
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• 2001

인버터를 적용한 유압식 엘리베이터 시스템은 펌프의 마찰과 실린더 패킹 및 탑승카와 레일의 마찰특성으로 인하여 PID 제어기로는 제어가 되지 않는 데드존이 생기게 된다. 본 논문에서는, 이러한 문제를 해결하기 위하여 먼저, 퍼지제어기와 PID제어기를 혼용하는 하이브리드제어기를 이용하는 방법을 시도한다. 그러나, 인버터를 적용한 유압식 엘리베이터는 비선형성이 강한 시스템이므로 두 제어기의 출력이 절환 되어야 하는 경계층이 다수인 경우가 대부분인데 반하여, 기존의 하이브리드제어기는 두 제어기의 출력이 절환되는 특정구간의 경계층을 제외하고는 전체 운전구간에서는 어느 한 제어기에만 영향을 받게 되므로 제어성능에 문제를 가지게 된다. 이에 따라 본 논문에서는, 출력혼합기의 출력비를 퍼지로직에 의하여 변경시키는 새로운 퍼지하이브리드제어기를 제안하여 기존의 하이브리드제어기의 문제점을 해결한다. 제안된 퍼지하이브리드제어기는 시스템의 상태에 따라서 두 제어기의 출력비를 달리하여 사용하는 방법으로 향상된 제어성능을 달성한다. 시뮬레이션 결과를 통하여, 제안된 퍼지하이브리드제어기가 극저속 속도영역에서 뿐 아니라 정상상태를 포함한 전 운전 영역에서의 제어 성능이 우수함을 보였다.

• 대한전자공학회논문지SD
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• 제44권4호
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• pp.55-62
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• 2007

본 논문에서는 이미지 센서에서 불량 화소를 자동으로 검출하기 위한 알고리듬을 제안하고, 그에 따른 하드웨어 구조를 제시하였다. 기존에 제안된 방법은 영상의 특징을 고려하지 않고 단순히 주위 화소들 값과의 차이가 일정 이상이면 불량 화소로 간주하였다. 그러나 이러한 방식은 영상에 따라서 불량 화소가 아닌 화소를 불량 화소로 간주하거나, 불량 화소를 정상 화소로 판단하는 일이 발생한다. 이러한 단점을 보완하기 위해 여러 프레임에 걸쳐 확인하는 방법도 제안되었으나, 불량 화소 검출시간이 오래 걸리는 단점이 있다. 이러한 기존 방식의 단점을 해결하기 위해, 제안된 불량 화소 검출 기법은 단일화면 내에서는 경계 영역을 고려하여 불량 화소를 검출하고, 여러 프레임에 걸친 확인 과정을 거치되, 화면 전환 여부를 확인하여 화면 전환이 일어날 때마다 검출된 화소의 불량 화소 여부를 판단하고 확인한다. 실험 결과, 단일 화면 내에서의 검출률은 기존 대비 6% 향상되었고, 100%의 불량화소 검출까지 걸리는 시간은 평균적으로 3배 이상 단축되었다. 본 논문에서 제안된 알고리듬은 하드웨어로 구현되었고, 하드웨어 구현 시 색 보간 블록에서 사용되는 경계 영역 표시자를 그대로 활용함으로써 0.25um 표준 셀 라이브러리를 이용하여 합성했을 때, 5.4K gate의 낮은 복잡도로 구현할 수 있었다.

• Journal of Radiation Protection and Research
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• 제45권2호
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• pp.76-80
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• 2020

Background: To improve the measurement accuracy of liquid-scintillation counting for activity standardization, it is necessary to significantly reduce the background caused by thermal noise or after-pulses. We have therefore improved a movable 3 photomultiplier (3PM)-γ coincidence-counting method using the logical sum of three double coincidences for β events. Materials and Methods: We designed a new data-acquisition system in which β events are obtained by counting the logical sum of three double coincidences. The change in β-detection efficiency can be derived by moving three photomultiplier tubes sequentially from the liquid-scintillation vial. The validity of the method was investigated by activity measurement of ¹³⁴Cs calibrated at the Korea Research Institute of Standards and Science (KRISS) with 4π(PC)β-γ(NaI(Tl)) coincidence counting using a proportional counter (PC) for the β detector. Results and Discussion: Measurements were taken over 14 counting intervals for each liquidscintillation sample by displacing three photomultiplier tubes up to 45 mm from the sample. The dead time in each β- and γ-counting channel was adjusted to be a non-extending type of 20 ㎲. The background ranged about 1.2-3.3 s^-1, such that the contributions of thermal noise or after-pulses were negligible. As the β-detection unit was moved away from the sample, the β-detection efficiencies varied between 0.54 and 0.81. The result obtained by the method at the reference date was 396.3 ± 1.7 kBq/g. This is consistent with the KRISS-certified value of 396.0 ± 2.0 kBq/g within the uncertainty range. Conclusion: The movable 3PM-γ method developed in the present work not only succeeded in reducing background counts to negligible levels but enabled β-detection efficiency to be varied by a geometrical method to apply the efficiency extrapolation method. Compared with our earlier work shown in the study of Hwang et al. [2], the measurement accuracy has much improved. Consequently, the method developed in this study is an improved method suitable for activity standardization of β-γ emitters.

• 대한의생명과학회지
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• 제3권2호
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• pp.77-82
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• 1997

Trichosporonoides madida와 같이 자연계에서 새로 분리된 균종을 산업 분야에서 이용하기 위하여 이들 균종의 제반성상을 명확히 확인하여야 함은 물론 분리균주의 병원성에 관한 연구가 필수적이다. 본 실험에서는 자연계에서 분리된 T. madida 분리균주의 제반성상을 확인하고 실험동물에 대한 병원성 여부를 체계적으로 조사하여 산업미생물로서의 이용 가능성에 대한 안전성을 검증하였다. 본 실험에 사용한 T. madida N-5-3 분리 균주의 생화학적, 형태학적인 특성은 전형적인 T. madida 균주의 미생물학적인 특징과 모두 일치하였다. T. madida N-5-3 균주의 실험용mouse에서의 복강내 투여 치사량 $(LD_{50})$은 실험에 사용한 $1{\times}10^1$에서부터 $1{\times}10^8$ 투여 시까지 사망하는 동물이 관찰되지 않아 $1{\times}10^8$ 이상인 것으로 확인되었다. 또 $1{\times}10^8$의 시험균주를 실험용 mouse의 복강에 접종한 후 각 시기 별로 심장, 폐, 간, 비장 및 신장에서의 시험균주의 증식 여부를 조사한 결과 간과 비장에서만 접종 후 2일까지 $1{\times}10^{4.3}$에서 $1{\times}10^{2.87}$의 시험균주가 분리되었으나 접종 4일째부터는 시험기간 완료일까지 접종균주가 전혀 관찰되지 않아 실험동물 체내에서 신속히 제거되는 것으로 나타났다. 한편 시험균주 접종에 따른 mouse내부장기의 조직학적인 변화를 조사한 결과 특징적인 병리학적 소견을 관찰할 수 없었다. 이상의 결과를 종합하여 볼 때 T. madida N-5-3 분리균주는 산업분야에서 이용시 공중보건학적인 관점에서 비병원성 균주이며 안전한 균주인 것으로 판단된다.